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author | redman <redman> | 1999-04-19 21:01:42 (GMT) |
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committer | redman <redman> | 1999-04-19 21:01:42 (GMT) |
commit | 948241a923a6cffbef3ef33cee41e8fe71addb0f (patch) | |
tree | 005f5c920d93289a50e9b1c8fee10732ee975779 | |
parent | 720d53ff1769ebd243a925952b781ee768d152bb (diff) | |
download | tcl-948241a923a6cffbef3ef33cee41e8fe71addb0f.zip tcl-948241a923a6cffbef3ef33cee41e8fe71addb0f.tar.gz tcl-948241a923a6cffbef3ef33cee41e8fe71addb0f.tar.bz2 |
Added comment about not check for EINTR [Bug 1631].
-rw-r--r-- | generic/tclIO.c | 7610 |
1 files changed, 7610 insertions, 0 deletions
diff --git a/generic/tclIO.c b/generic/tclIO.c new file mode 100644 index 0000000..7d5f31a --- /dev/null +++ b/generic/tclIO.c @@ -0,0 +1,7610 @@ +/* + * tclIO.c -- + * + * This file provides the generic portions (those that are the same on + * all platforms and for all channel types) of Tcl's IO facilities. + * + * Copyright (c) 1998 Scriptics Corporation + * Copyright (c) 1995-1997 Sun Microsystems, Inc. + * + * See the file "license.terms" for information on usage and redistribution + * of this file, and for a DISCLAIMER OF ALL WARRANTIES. + * + * RCS: @(#) $Id: tclIO.c,v 1.6.2.1 1999/04/19 21:01:42 redman Exp $ + */ + +#include "tclInt.h" +#include "tclPort.h" + +/* + * Make sure that both EAGAIN and EWOULDBLOCK are defined. This does not + * compile on systems where neither is defined. We want both defined so + * that we can test safely for both. In the code we still have to test for + * both because there may be systems on which both are defined and have + * different values. + */ + +#if ((!defined(EWOULDBLOCK)) && (defined(EAGAIN))) +# define EWOULDBLOCK EAGAIN +#endif +#if ((!defined(EAGAIN)) && (defined(EWOULDBLOCK))) +# define EAGAIN EWOULDBLOCK +#endif +#if ((!defined(EAGAIN)) && (!defined(EWOULDBLOCK))) + error one of EWOULDBLOCK or EAGAIN must be defined +#endif + +/* + * The following structure encapsulates the state for a background channel + * copy. Note that the data buffer for the copy will be appended to this + * structure. + */ + +typedef struct CopyState { + struct Channel *readPtr; /* Pointer to input channel. */ + struct Channel *writePtr; /* Pointer to output channel. */ + int readFlags; /* Original read channel flags. */ + int writeFlags; /* Original write channel flags. */ + int toRead; /* Number of bytes to copy, or -1. */ + int total; /* Total bytes transferred (written). */ + Tcl_Interp *interp; /* Interp that started the copy. */ + Tcl_Obj *cmdPtr; /* Command to be invoked at completion. */ + int bufSize; /* Size of appended buffer. */ + char buffer[1]; /* Copy buffer, this must be the last + * field. */ +} CopyState; + +/* + * struct ChannelBuffer: + * + * Buffers data being sent to or from a channel. + */ + +typedef struct ChannelBuffer { + int nextAdded; /* The next position into which a character + * will be put in the buffer. */ + int nextRemoved; /* Position of next byte to be removed + * from the buffer. */ + int bufLength; /* How big is the buffer? */ + struct ChannelBuffer *nextPtr; + /* Next buffer in chain. */ + char buf[4]; /* Placeholder for real buffer. The real + * buffer occuppies this space + bufSize-4 + * bytes. This must be the last field in + * the structure. */ +} ChannelBuffer; + +#define CHANNELBUFFER_HEADER_SIZE (sizeof(ChannelBuffer) - 4) + +/* + * How much extra space to allocate in buffer to hold bytes from previous + * buffer (when converting to UTF-8) or to hold bytes that will go to + * next buffer (when converting from UTF-8). + */ + +#define BUFFER_PADDING 16 + +/* + * The following defines the *default* buffer size for channels. + */ + +#define CHANNELBUFFER_DEFAULT_SIZE (1024 * 4) + +/* + * Structure to record a close callback. One such record exists for + * each close callback registered for a channel. + */ + +typedef struct CloseCallback { + Tcl_CloseProc *proc; /* The procedure to call. */ + ClientData clientData; /* Arbitrary one-word data to pass + * to the callback. */ + struct CloseCallback *nextPtr; /* For chaining close callbacks. */ +} CloseCallback; + +/* + * The following structure describes the information saved from a call to + * "fileevent". This is used later when the event being waited for to + * invoke the saved script in the interpreter designed in this record. + */ + +typedef struct EventScriptRecord { + struct Channel *chanPtr; /* The channel for which this script is + * registered. This is used only when an + * error occurs during evaluation of the + * script, to delete the handler. */ + Tcl_Obj *scriptPtr; /* Script to invoke. */ + Tcl_Interp *interp; /* In what interpreter to invoke script? */ + int mask; /* Events must overlap current mask for the + * stored script to be invoked. */ + struct EventScriptRecord *nextPtr; + /* Next in chain of records. */ +} EventScriptRecord; + +/* + * struct Channel: + * + * One of these structures is allocated for each open channel. It contains data + * specific to the channel but which belongs to the generic part of the Tcl + * channel mechanism, and it points at an instance specific (and type + * specific) * instance data, and at a channel type structure. + */ + +typedef struct Channel { + char *channelName; /* The name of the channel instance in Tcl + * commands. Storage is owned by the generic IO + * code, is dynamically allocated. */ + int flags; /* ORed combination of the flags defined + * below. */ + Tcl_Encoding encoding; /* Encoding to apply when reading or writing + * data on this channel. NULL means no + * encoding is applied to data. */ + Tcl_EncodingState inputEncodingState; + /* Current encoding state, used when converting + * input data bytes to UTF-8. */ + int inputEncodingFlags; /* Encoding flags to pass to conversion + * routine when converting input data bytes to + * UTF-8. May be TCL_ENCODING_START before + * converting first byte and TCL_ENCODING_END + * when EOF is seen. */ + Tcl_EncodingState outputEncodingState; + /* Current encoding state, used when converting + * UTF-8 to output data bytes. */ + int outputEncodingFlags; /* Encoding flags to pass to conversion + * routine when converting UTF-8 to output + * data bytes. May be TCL_ENCODING_START + * before converting first byte and + * TCL_ENCODING_END when EOF is seen. */ + Tcl_EolTranslation inputTranslation; + /* What translation to apply for end of line + * sequences on input? */ + Tcl_EolTranslation outputTranslation; + /* What translation to use for generating + * end of line sequences in output? */ + int inEofChar; /* If nonzero, use this as a signal of EOF + * on input. */ + int outEofChar; /* If nonzero, append this to the channel + * when it is closed if it is open for + * writing. */ + int unreportedError; /* Non-zero if an error report was deferred + * because it happened in the background. The + * value is the POSIX error code. */ + ClientData instanceData; /* Instance-specific data provided by + * creator of channel. */ + + Tcl_ChannelType *typePtr; /* Pointer to channel type structure. */ + int refCount; /* How many interpreters hold references to + * this IO channel? */ + CloseCallback *closeCbPtr; /* Callbacks registered to be called when the + * channel is closed. */ + char *outputStage; /* Temporary staging buffer used when + * translating EOL before converting from + * UTF-8 to external form. */ + ChannelBuffer *curOutPtr; /* Current output buffer being filled. */ + ChannelBuffer *outQueueHead;/* Points at first buffer in output queue. */ + ChannelBuffer *outQueueTail;/* Points at last buffer in output queue. */ + + ChannelBuffer *saveInBufPtr;/* Buffer saved for input queue - eliminates + * need to allocate a new buffer for "gets" + * that crosses buffer boundaries. */ + ChannelBuffer *inQueueHead; /* Points at first buffer in input queue. */ + ChannelBuffer *inQueueTail; /* Points at last buffer in input queue. */ + + struct ChannelHandler *chPtr;/* List of channel handlers registered + * for this channel. */ + int interestMask; /* Mask of all events this channel has + * handlers for. */ + struct Channel *nextChanPtr;/* Next in list of channels currently open. */ + EventScriptRecord *scriptRecordPtr; + /* Chain of all scripts registered for + * event handlers ("fileevent") on this + * channel. */ + int bufSize; /* What size buffers to allocate? */ + Tcl_TimerToken timer; /* Handle to wakeup timer for this channel. */ + CopyState *csPtr; /* State of background copy, or NULL. */ +} Channel; + +/* + * Values for the flags field in Channel. Any ORed combination of the + * following flags can be stored in the field. These flags record various + * options and state bits about the channel. In addition to the flags below, + * the channel can also have TCL_READABLE (1<<1) and TCL_WRITABLE (1<<2) set. + */ + +#define CHANNEL_NONBLOCKING (1<<3) /* Channel is currently in + * nonblocking mode. */ +#define CHANNEL_LINEBUFFERED (1<<4) /* Output to the channel must be + * flushed after every newline. */ +#define CHANNEL_UNBUFFERED (1<<5) /* Output to the channel must always + * be flushed immediately. */ +#define BUFFER_READY (1<<6) /* Current output buffer (the + * curOutPtr field in the + * channel structure) should be + * output as soon as possible even + * though it may not be full. */ +#define BG_FLUSH_SCHEDULED (1<<7) /* A background flush of the + * queued output buffers has been + * scheduled. */ +#define CHANNEL_CLOSED (1<<8) /* Channel has been closed. No + * further Tcl-level IO on the + * channel is allowed. */ +#define CHANNEL_EOF (1<<9) /* EOF occurred on this channel. + * This bit is cleared before every + * input operation. */ +#define CHANNEL_STICKY_EOF (1<<10) /* EOF occurred on this channel because + * we saw the input eofChar. This bit + * prevents clearing of the EOF bit + * before every input operation. */ +#define CHANNEL_BLOCKED (1<<11) /* EWOULDBLOCK or EAGAIN occurred + * on this channel. This bit is + * cleared before every input or + * output operation. */ +#define INPUT_SAW_CR (1<<12) /* Channel is in CRLF eol input + * translation mode and the last + * byte seen was a "\r". */ +#define INPUT_NEED_NL (1<<15) /* Saw a '\r' at end of last buffer, + * and there should be a '\n' at + * beginning of next buffer. */ +#define CHANNEL_DEAD (1<<13) /* The channel has been closed by + * the exit handler (on exit) but + * not deallocated. When any IO + * operation sees this flag on a + * channel, it does not call driver + * level functions to avoid referring + * to deallocated data. */ +#define CHANNEL_NEED_MORE_DATA (1<<14) /* The last input operation failed + * because there was not enough data + * to complete the operation. This + * flag is set when gets fails to + * get a complete line or when read + * fails to get a complete character. + * When set, file events will not be + * delivered for buffered data until + * the state of the channel changes. */ + +/* + * For each channel handler registered in a call to Tcl_CreateChannelHandler, + * there is one record of the following type. All of records for a specific + * channel are chained together in a singly linked list which is stored in + * the channel structure. + */ + +typedef struct ChannelHandler { + Channel *chanPtr; /* The channel structure for this channel. */ + int mask; /* Mask of desired events. */ + Tcl_ChannelProc *proc; /* Procedure to call in the type of + * Tcl_CreateChannelHandler. */ + ClientData clientData; /* Argument to pass to procedure. */ + struct ChannelHandler *nextPtr; + /* Next one in list of registered handlers. */ +} ChannelHandler; + +/* + * This structure keeps track of the current ChannelHandler being invoked in + * the current invocation of ChannelHandlerEventProc. There is a potential + * problem if a ChannelHandler is deleted while it is the current one, since + * ChannelHandlerEventProc needs to look at the nextPtr field. To handle this + * problem, structures of the type below indicate the next handler to be + * processed for any (recursively nested) dispatches in progress. The + * nextHandlerPtr field is updated if the handler being pointed to is deleted. + * The nextPtr field is used to chain together all recursive invocations, so + * that Tcl_DeleteChannelHandler can find all the recursively nested + * invocations of ChannelHandlerEventProc and compare the handler being + * deleted against the NEXT handler to be invoked in that invocation; when it + * finds such a situation, Tcl_DeleteChannelHandler updates the nextHandlerPtr + * field of the structure to the next handler. + */ + +typedef struct NextChannelHandler { + ChannelHandler *nextHandlerPtr; /* The next handler to be invoked in + * this invocation. */ + struct NextChannelHandler *nestedHandlerPtr; + /* Next nested invocation of + * ChannelHandlerEventProc. */ +} NextChannelHandler; + + +/* + * The following structure describes the event that is added to the Tcl + * event queue by the channel handler check procedure. + */ + +typedef struct ChannelHandlerEvent { + Tcl_Event header; /* Standard header for all events. */ + Channel *chanPtr; /* The channel that is ready. */ + int readyMask; /* Events that have occurred. */ +} ChannelHandlerEvent; + +/* + * The following structure is used by Tcl_GetsObj() to encapsulates the + * state for a "gets" operation. + */ + +typedef struct GetsState { + Tcl_Obj *objPtr; /* The object to which UTF-8 characters + * will be appended. */ + char **dstPtr; /* Pointer into objPtr's string rep where + * next character should be stored. */ + Tcl_Encoding encoding; /* The encoding to use to convert raw bytes + * to UTF-8. */ + ChannelBuffer *bufPtr; /* The current buffer of raw bytes being + * emptied. */ + Tcl_EncodingState state; /* The encoding state just before the last + * external to UTF-8 conversion in + * FilterInputBytes(). */ + int rawRead; /* The number of bytes removed from bufPtr + * in the last call to FilterInputBytes(). */ + int bytesWrote; /* The number of bytes of UTF-8 data + * appended to objPtr during the last call to + * FilterInputBytes(). */ + int charsWrote; /* The corresponding number of UTF-8 + * characters appended to objPtr during the + * last call to FilterInputBytes(). */ + int totalChars; /* The total number of UTF-8 characters + * appended to objPtr so far, just before the + * last call to FilterInputBytes(). */ +} GetsState; + +/* + * All static variables used in this file are collected into a single + * instance of the following structure. For multi-threaded implementations, + * there is one instance of this structure for each thread. + * + * Notice that different structures with the same name appear in other + * files. The structure defined below is used in this file only. + */ + +typedef struct ThreadSpecificData { + + /* + * This variable holds the list of nested ChannelHandlerEventProc + * invocations. + */ + NextChannelHandler *nestedHandlerPtr; + + /* + * List of all channels currently open. + */ + Channel *firstChanPtr; +#ifdef oldcode + /* + * Has a channel exit handler been created yet? + */ + int channelExitHandlerCreated; + + /* + * Has the channel event source been created and registered with the + * notifier? + */ + int channelEventSourceCreated; +#endif + /* + * Static variables to hold channels for stdin, stdout and stderr. + */ + Tcl_Channel stdinChannel; + int stdinInitialized; + Tcl_Channel stdoutChannel; + int stdoutInitialized; + Tcl_Channel stderrChannel; + int stderrInitialized; + +} ThreadSpecificData; + +static Tcl_ThreadDataKey dataKey; + + +/* + * Static functions in this file: + */ + +static ChannelBuffer * AllocChannelBuffer _ANSI_ARGS_((int length)); +static void ChannelEventScriptInvoker _ANSI_ARGS_(( + ClientData clientData, int flags)); +static void ChannelTimerProc _ANSI_ARGS_(( + ClientData clientData)); +static int CheckChannelErrors _ANSI_ARGS_((Channel *chanPtr, + int direction)); +static int CheckFlush _ANSI_ARGS_((Channel *chanPtr, + ChannelBuffer *bufPtr, int newlineFlag)); +static int CheckForDeadChannel _ANSI_ARGS_((Tcl_Interp *interp, + Channel *chan)); +static void CheckForStdChannelsBeingClosed _ANSI_ARGS_(( + Tcl_Channel chan)); +static void CleanupChannelHandlers _ANSI_ARGS_(( + Tcl_Interp *interp, Channel *chanPtr)); +static int CloseChannel _ANSI_ARGS_((Tcl_Interp *interp, + Channel *chanPtr, int errorCode)); +static void CommonGetsCleanup _ANSI_ARGS_((Channel *chanPtr, + Tcl_Encoding encoding)); +static int CopyAndTranslateBuffer _ANSI_ARGS_(( + Channel *chanPtr, char *result, int space)); +static int CopyData _ANSI_ARGS_((CopyState *csPtr, int mask)); +static void CopyEventProc _ANSI_ARGS_((ClientData clientData, + int mask)); +static void CreateScriptRecord _ANSI_ARGS_(( + Tcl_Interp *interp, Channel *chanPtr, + int mask, Tcl_Obj *scriptPtr)); +static void DeleteChannelTable _ANSI_ARGS_(( + ClientData clientData, Tcl_Interp *interp)); +static void DeleteScriptRecord _ANSI_ARGS_((Tcl_Interp *interp, + Channel *chanPtr, int mask)); +static void DiscardInputQueued _ANSI_ARGS_(( + Channel *chanPtr, int discardSavedBuffers)); +static void DiscardOutputQueued _ANSI_ARGS_(( + Channel *chanPtr)); +static int DoRead _ANSI_ARGS_((Channel *chanPtr, char *srcPtr, + int slen)); +static int DoWrite _ANSI_ARGS_((Channel *chanPtr, char *src, + int srcLen)); +static int FilterInputBytes _ANSI_ARGS_((Channel *chanPtr, + GetsState *statePtr)); +static int FlushChannel _ANSI_ARGS_((Tcl_Interp *interp, + Channel *chanPtr, int calledFromAsyncFlush)); +static Tcl_HashTable * GetChannelTable _ANSI_ARGS_((Tcl_Interp *interp)); +static int GetInput _ANSI_ARGS_((Channel *chanPtr)); +static void PeekAhead _ANSI_ARGS_((Channel *chanPtr, + char **dstEndPtr, GetsState *gsPtr)); +static int ReadBytes _ANSI_ARGS_((Channel *chanPtr, + Tcl_Obj *objPtr, int charsLeft, int *offsetPtr)); +static int ReadChars _ANSI_ARGS_((Channel *chanPtr, + Tcl_Obj *objPtr, int charsLeft, int *offsetPtr, + int *factorPtr)); +static void RecycleBuffer _ANSI_ARGS_((Channel *chanPtr, + ChannelBuffer *bufPtr, int mustDiscard)); +static int SetBlockMode _ANSI_ARGS_((Tcl_Interp *interp, + Channel *chanPtr, int mode)); +static void StopCopy _ANSI_ARGS_((CopyState *csPtr)); +static int TranslateInputEOL _ANSI_ARGS_((Channel *chanPtr, + char *dst, CONST char *src, int *dstLenPtr, + int *srcLenPtr)); +static int TranslateOutputEOL _ANSI_ARGS_((Channel *chanPtr, + char *dst, CONST char *src, int *dstLenPtr, + int *srcLenPtr)); +static void UpdateInterest _ANSI_ARGS_((Channel *chanPtr)); +static int WriteBytes _ANSI_ARGS_((Channel *chanPtr, + CONST char *src, int srcLen)); +static int WriteChars _ANSI_ARGS_((Channel *chanPtr, + CONST char *src, int srcLen)); + + +/* + *--------------------------------------------------------------------------- + * + * TclInitIOSubsystem -- + * + * Initialize all resources used by this subsystem on a per-process + * basis. + * + * Results: + * None. + * + * Side effects: + * Depends on the memory subsystems. + * + *--------------------------------------------------------------------------- + */ + +void +TclInitIOSubsystem() +{ + /* + * By fetching thread local storage we take care of + * allocating it for each thread. + */ + (void) TCL_TSD_INIT(&dataKey); +} + +/* + *------------------------------------------------------------------------- + * + * TclFinalizeIOSubsystem -- + * + * Releases all resources used by this subsystem on a per-process + * basis. Closes all extant channels that have not already been + * closed because they were not owned by any interp. + * + * Results: + * None. + * + * Side effects: + * Depends on encoding and memory subsystems. + * + *------------------------------------------------------------------------- + */ + + /* ARGSUSED */ +void +TclFinalizeIOSubsystem() +{ + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + Channel *chanPtr; /* Iterates over open channels. */ + Channel *nextChanPtr; /* Iterates over open channels. */ + + + for (chanPtr = tsdPtr->firstChanPtr; chanPtr != (Channel *) NULL; + chanPtr = nextChanPtr) { + nextChanPtr = chanPtr->nextChanPtr; + + /* + * Set the channel back into blocking mode to ensure that we wait + * for all data to flush out. + */ + + (void) Tcl_SetChannelOption(NULL, (Tcl_Channel) chanPtr, + "-blocking", "on"); + + if ((chanPtr == (Channel *) tsdPtr->stdinChannel) || + (chanPtr == (Channel *) tsdPtr->stdoutChannel) || + (chanPtr == (Channel *) tsdPtr->stderrChannel)) { + + /* + * Decrement the refcount which was earlier artificially bumped + * up to keep the channel from being closed. + */ + + chanPtr->refCount--; + } + + if (chanPtr->refCount <= 0) { + + /* + * Close it only if the refcount indicates that the channel is not + * referenced from any interpreter. If it is, that interpreter will + * close the channel when it gets destroyed. + */ + + (void) Tcl_Close((Tcl_Interp *) NULL, (Tcl_Channel) chanPtr); + + } else { + + /* + * The refcount is greater than zero, so flush the channel. + */ + + Tcl_Flush((Tcl_Channel) chanPtr); + + /* + * Call the device driver to actually close the underlying + * device for this channel. + */ + + if (chanPtr->typePtr->closeProc != TCL_CLOSE2PROC) { + (chanPtr->typePtr->closeProc)(chanPtr->instanceData, + (Tcl_Interp *) NULL); + } else { + (chanPtr->typePtr->close2Proc)(chanPtr->instanceData, + (Tcl_Interp *) NULL, 0); + } + + /* + * Finally, we clean up the fields in the channel data structure + * since all of them have been deleted already. We mark the + * channel with CHANNEL_DEAD to prevent any further IO operations + * on it. + */ + + chanPtr->instanceData = (ClientData) NULL; + chanPtr->flags |= CHANNEL_DEAD; + } + } +} + + + +/* + *---------------------------------------------------------------------- + * + * Tcl_SetStdChannel -- + * + * This function is used to change the channels that are used + * for stdin/stdout/stderr in new interpreters. + * + * Results: + * None + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_SetStdChannel(channel, type) + Tcl_Channel channel; + int type; /* One of TCL_STDIN, TCL_STDOUT, TCL_STDERR. */ +{ + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + switch (type) { + case TCL_STDIN: + tsdPtr->stdinInitialized = 1; + tsdPtr->stdinChannel = channel; + break; + case TCL_STDOUT: + tsdPtr->stdoutInitialized = 1; + tsdPtr->stdoutChannel = channel; + break; + case TCL_STDERR: + tsdPtr->stderrInitialized = 1; + tsdPtr->stderrChannel = channel; + break; + } +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetStdChannel -- + * + * Returns the specified standard channel. + * + * Results: + * Returns the specified standard channel, or NULL. + * + * Side effects: + * May cause the creation of a standard channel and the underlying + * file. + * + *---------------------------------------------------------------------- + */ +Tcl_Channel +Tcl_GetStdChannel(type) + int type; /* One of TCL_STDIN, TCL_STDOUT, TCL_STDERR. */ +{ + Tcl_Channel channel = NULL; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + /* + * If the channels were not created yet, create them now and + * store them in the static variables. + */ + + switch (type) { + case TCL_STDIN: + if (!tsdPtr->stdinInitialized) { + tsdPtr->stdinChannel = TclpGetDefaultStdChannel(TCL_STDIN); + tsdPtr->stdinInitialized = 1; + + /* + * Artificially bump the refcount to ensure that the channel + * is only closed on exit. + * + * NOTE: Must only do this if stdinChannel is not NULL. It + * can be NULL in situations where Tcl is unable to connect + * to the standard input. + */ + + if (tsdPtr->stdinChannel != (Tcl_Channel) NULL) { + (void) Tcl_RegisterChannel((Tcl_Interp *) NULL, + tsdPtr->stdinChannel); + } + } + channel = tsdPtr->stdinChannel; + break; + case TCL_STDOUT: + if (!tsdPtr->stdoutInitialized) { + tsdPtr->stdoutChannel = TclpGetDefaultStdChannel(TCL_STDOUT); + tsdPtr->stdoutInitialized = 1; + if (tsdPtr->stdoutChannel != (Tcl_Channel) NULL) { + (void) Tcl_RegisterChannel((Tcl_Interp *) NULL, + tsdPtr->stdoutChannel); + } + } + channel = tsdPtr->stdoutChannel; + break; + case TCL_STDERR: + if (!tsdPtr->stderrInitialized) { + tsdPtr->stderrChannel = TclpGetDefaultStdChannel(TCL_STDERR); + tsdPtr->stderrInitialized = 1; + if (tsdPtr->stderrChannel != (Tcl_Channel) NULL) { + (void) Tcl_RegisterChannel((Tcl_Interp *) NULL, + tsdPtr->stderrChannel); + } + } + channel = tsdPtr->stderrChannel; + break; + } + return channel; +} + + +/* + *---------------------------------------------------------------------- + * + * Tcl_CreateCloseHandler + * + * Creates a close callback which will be called when the channel is + * closed. + * + * Results: + * None. + * + * Side effects: + * Causes the callback to be called in the future when the channel + * will be closed. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_CreateCloseHandler(chan, proc, clientData) + Tcl_Channel chan; /* The channel for which to create the + * close callback. */ + Tcl_CloseProc *proc; /* The callback routine to call when the + * channel will be closed. */ + ClientData clientData; /* Arbitrary data to pass to the + * close callback. */ +{ + Channel *chanPtr; + CloseCallback *cbPtr; + + chanPtr = (Channel *) chan; + + cbPtr = (CloseCallback *) ckalloc((unsigned) sizeof(CloseCallback)); + cbPtr->proc = proc; + cbPtr->clientData = clientData; + + cbPtr->nextPtr = chanPtr->closeCbPtr; + chanPtr->closeCbPtr = cbPtr; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_DeleteCloseHandler -- + * + * Removes a callback that would have been called on closing + * the channel. If there is no matching callback then this + * function has no effect. + * + * Results: + * None. + * + * Side effects: + * The callback will not be called in the future when the channel + * is eventually closed. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_DeleteCloseHandler(chan, proc, clientData) + Tcl_Channel chan; /* The channel for which to cancel the + * close callback. */ + Tcl_CloseProc *proc; /* The procedure for the callback to + * remove. */ + ClientData clientData; /* The callback data for the callback + * to remove. */ +{ + Channel *chanPtr; + CloseCallback *cbPtr, *cbPrevPtr; + + chanPtr = (Channel *) chan; + for (cbPtr = chanPtr->closeCbPtr, cbPrevPtr = (CloseCallback *) NULL; + cbPtr != (CloseCallback *) NULL; + cbPtr = cbPtr->nextPtr) { + if ((cbPtr->proc == proc) && (cbPtr->clientData == clientData)) { + if (cbPrevPtr == (CloseCallback *) NULL) { + chanPtr->closeCbPtr = cbPtr->nextPtr; + } + ckfree((char *) cbPtr); + break; + } else { + cbPrevPtr = cbPtr; + } + } +} + +/* + *---------------------------------------------------------------------- + * + * GetChannelTable -- + * + * Gets and potentially initializes the channel table for an + * interpreter. If it is initializing the table it also inserts + * channels for stdin, stdout and stderr if the interpreter is + * trusted. + * + * Results: + * A pointer to the hash table created, for use by the caller. + * + * Side effects: + * Initializes the channel table for an interpreter. May create + * channels for stdin, stdout and stderr. + * + *---------------------------------------------------------------------- + */ + +static Tcl_HashTable * +GetChannelTable(interp) + Tcl_Interp *interp; +{ + Tcl_HashTable *hTblPtr; /* Hash table of channels. */ + Tcl_Channel stdinChan, stdoutChan, stderrChan; + + hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); + if (hTblPtr == (Tcl_HashTable *) NULL) { + hTblPtr = (Tcl_HashTable *) ckalloc((unsigned) sizeof(Tcl_HashTable)); + Tcl_InitHashTable(hTblPtr, TCL_STRING_KEYS); + + (void) Tcl_SetAssocData(interp, "tclIO", + (Tcl_InterpDeleteProc *) DeleteChannelTable, + (ClientData) hTblPtr); + + /* + * If the interpreter is trusted (not "safe"), insert channels + * for stdin, stdout and stderr (possibly creating them in the + * process). + */ + + if (Tcl_IsSafe(interp) == 0) { + stdinChan = Tcl_GetStdChannel(TCL_STDIN); + if (stdinChan != NULL) { + Tcl_RegisterChannel(interp, stdinChan); + } + stdoutChan = Tcl_GetStdChannel(TCL_STDOUT); + if (stdoutChan != NULL) { + Tcl_RegisterChannel(interp, stdoutChan); + } + stderrChan = Tcl_GetStdChannel(TCL_STDERR); + if (stderrChan != NULL) { + Tcl_RegisterChannel(interp, stderrChan); + } + } + + } + return hTblPtr; +} + +/* + *---------------------------------------------------------------------- + * + * DeleteChannelTable -- + * + * Deletes the channel table for an interpreter, closing any open + * channels whose refcount reaches zero. This procedure is invoked + * when an interpreter is deleted, via the AssocData cleanup + * mechanism. + * + * Results: + * None. + * + * Side effects: + * Deletes the hash table of channels. May close channels. May flush + * output on closed channels. Removes any channeEvent handlers that were + * registered in this interpreter. + * + *---------------------------------------------------------------------- + */ + +static void +DeleteChannelTable(clientData, interp) + ClientData clientData; /* The per-interpreter data structure. */ + Tcl_Interp *interp; /* The interpreter being deleted. */ +{ + Tcl_HashTable *hTblPtr; /* The hash table. */ + Tcl_HashSearch hSearch; /* Search variable. */ + Tcl_HashEntry *hPtr; /* Search variable. */ + Channel *chanPtr; /* Channel being deleted. */ + EventScriptRecord *sPtr, *prevPtr, *nextPtr; + /* Variables to loop over all channel events + * registered, to delete the ones that refer + * to the interpreter being deleted. */ + + /* + * Delete all the registered channels - this will close channels whose + * refcount reaches zero. + */ + + hTblPtr = (Tcl_HashTable *) clientData; + for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); + hPtr != (Tcl_HashEntry *) NULL; + hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch)) { + + chanPtr = (Channel *) Tcl_GetHashValue(hPtr); + + /* + * Remove any fileevents registered in this interpreter. + */ + + for (sPtr = chanPtr->scriptRecordPtr, + prevPtr = (EventScriptRecord *) NULL; + sPtr != (EventScriptRecord *) NULL; + sPtr = nextPtr) { + nextPtr = sPtr->nextPtr; + if (sPtr->interp == interp) { + if (prevPtr == (EventScriptRecord *) NULL) { + chanPtr->scriptRecordPtr = nextPtr; + } else { + prevPtr->nextPtr = nextPtr; + } + + Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, + ChannelEventScriptInvoker, (ClientData) sPtr); + + Tcl_DecrRefCount(sPtr->scriptPtr); + ckfree((char *) sPtr); + } else { + prevPtr = sPtr; + } + } + + /* + * Cannot call Tcl_UnregisterChannel because that procedure calls + * Tcl_GetAssocData to get the channel table, which might already + * be inaccessible from the interpreter structure. Instead, we + * emulate the behavior of Tcl_UnregisterChannel directly here. + */ + + Tcl_DeleteHashEntry(hPtr); + chanPtr->refCount--; + if (chanPtr->refCount <= 0) { + if (!(chanPtr->flags & BG_FLUSH_SCHEDULED)) { + (void) Tcl_Close(interp, (Tcl_Channel) chanPtr); + } + } + } + Tcl_DeleteHashTable(hTblPtr); + ckfree((char *) hTblPtr); +} + +/* + *---------------------------------------------------------------------- + * + * CheckForStdChannelsBeingClosed -- + * + * Perform special handling for standard channels being closed. When + * given a standard channel, if the refcount is now 1, it means that + * the last reference to the standard channel is being explicitly + * closed. Now bump the refcount artificially down to 0, to ensure the + * normal handling of channels being closed will occur. Also reset the + * static pointer to the channel to NULL, to avoid dangling references. + * + * Results: + * None. + * + * Side effects: + * Manipulates the refcount on standard channels. May smash the global + * static pointer to a standard channel. + * + *---------------------------------------------------------------------- + */ + +static void +CheckForStdChannelsBeingClosed(chan) + Tcl_Channel chan; +{ + Channel *chanPtr = (Channel *) chan; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + if ((chan == tsdPtr->stdinChannel) && (tsdPtr->stdinInitialized)) { + if (chanPtr->refCount < 2) { + chanPtr->refCount = 0; + tsdPtr->stdinChannel = NULL; + return; + } + } else if ((chan == tsdPtr->stdoutChannel) && (tsdPtr->stdoutInitialized)) { + if (chanPtr->refCount < 2) { + chanPtr->refCount = 0; + tsdPtr->stdoutChannel = NULL; + return; + } + } else if ((chan == tsdPtr->stderrChannel) && (tsdPtr->stderrInitialized)) { + if (chanPtr->refCount < 2) { + chanPtr->refCount = 0; + tsdPtr->stderrChannel = NULL; + return; + } + } +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_RegisterChannel -- + * + * Adds an already-open channel to the channel table of an interpreter. + * If the interpreter passed as argument is NULL, it only increments + * the channel refCount. + * + * Results: + * None. + * + * Side effects: + * May increment the reference count of a channel. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_RegisterChannel(interp, chan) + Tcl_Interp *interp; /* Interpreter in which to add the channel. */ + Tcl_Channel chan; /* The channel to add to this interpreter + * channel table. */ +{ + Tcl_HashTable *hTblPtr; /* Hash table of channels. */ + Tcl_HashEntry *hPtr; /* Search variable. */ + int new; /* Is the hash entry new or does it exist? */ + Channel *chanPtr; /* The actual channel. */ + + chanPtr = (Channel *) chan; + + if (chanPtr->channelName == (char *) NULL) { + panic("Tcl_RegisterChannel: channel without name"); + } + if (interp != (Tcl_Interp *) NULL) { + hTblPtr = GetChannelTable(interp); + hPtr = Tcl_CreateHashEntry(hTblPtr, chanPtr->channelName, &new); + if (new == 0) { + if (chan == (Tcl_Channel) Tcl_GetHashValue(hPtr)) { + return; + } + panic("Tcl_RegisterChannel: duplicate channel names"); + } + Tcl_SetHashValue(hPtr, (ClientData) chanPtr); + } + chanPtr->refCount++; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_UnregisterChannel -- + * + * Deletes the hash entry for a channel associated with an interpreter. + * If the interpreter given as argument is NULL, it only decrements the + * reference count. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * Deletes the hash entry for a channel associated with an interpreter. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_UnregisterChannel(interp, chan) + Tcl_Interp *interp; /* Interpreter in which channel is defined. */ + Tcl_Channel chan; /* Channel to delete. */ +{ + Tcl_HashTable *hTblPtr; /* Hash table of channels. */ + Tcl_HashEntry *hPtr; /* Search variable. */ + Channel *chanPtr; /* The real IO channel. */ + + chanPtr = (Channel *) chan; + + if (interp != (Tcl_Interp *) NULL) { + hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); + if (hTblPtr == (Tcl_HashTable *) NULL) { + return TCL_OK; + } + hPtr = Tcl_FindHashEntry(hTblPtr, chanPtr->channelName); + if (hPtr == (Tcl_HashEntry *) NULL) { + return TCL_OK; + } + if ((Channel *) Tcl_GetHashValue(hPtr) != chanPtr) { + return TCL_OK; + } + Tcl_DeleteHashEntry(hPtr); + + /* + * Remove channel handlers that refer to this interpreter, so that they + * will not be present if the actual close is delayed and more events + * happen on the channel. This may occur if the channel is shared + * between several interpreters, or if the channel has async + * flushing active. + */ + + CleanupChannelHandlers(interp, chanPtr); + } + + chanPtr->refCount--; + + /* + * Perform special handling for standard channels being closed. If the + * refCount is now 1 it means that the last reference to the standard + * channel is being explicitly closed, so bump the refCount down + * artificially to 0. This will ensure that the channel is actually + * closed, below. Also set the static pointer to NULL for the channel. + */ + + CheckForStdChannelsBeingClosed(chan); + + /* + * If the refCount reached zero, close the actual channel. + */ + + if (chanPtr->refCount <= 0) { + + /* + * Ensure that if there is another buffer, it gets flushed + * whether or not we are doing a background flush. + */ + + if ((chanPtr->curOutPtr != NULL) && + (chanPtr->curOutPtr->nextAdded > + chanPtr->curOutPtr->nextRemoved)) { + chanPtr->flags |= BUFFER_READY; + } + chanPtr->flags |= CHANNEL_CLOSED; + if (!(chanPtr->flags & BG_FLUSH_SCHEDULED)) { + if (Tcl_Close(interp, chan) != TCL_OK) { + return TCL_ERROR; + } + } + } + return TCL_OK; +} + +/* + *--------------------------------------------------------------------------- + * + * Tcl_GetChannel -- + * + * Finds an existing Tcl_Channel structure by name in a given + * interpreter. This function is public because it is used by + * channel-type-specific functions. + * + * Results: + * A Tcl_Channel or NULL on failure. If failed, interp's result + * object contains an error message. *modePtr is filled with the + * modes in which the channel was opened. + * + * Side effects: + * None. + * + *--------------------------------------------------------------------------- + */ + +Tcl_Channel +Tcl_GetChannel(interp, chanName, modePtr) + Tcl_Interp *interp; /* Interpreter in which to find or create + * the channel. */ + char *chanName; /* The name of the channel. */ + int *modePtr; /* Where to store the mode in which the + * channel was opened? Will contain an ORed + * combination of TCL_READABLE and + * TCL_WRITABLE, if non-NULL. */ +{ + Channel *chanPtr; /* The actual channel. */ + Tcl_HashTable *hTblPtr; /* Hash table of channels. */ + Tcl_HashEntry *hPtr; /* Search variable. */ + char *name; /* Translated name. */ + + /* + * Substitute "stdin", etc. Note that even though we immediately + * find the channel using Tcl_GetStdChannel, we still need to look + * it up in the specified interpreter to ensure that it is present + * in the channel table. Otherwise, safe interpreters would always + * have access to the standard channels. + */ + + name = chanName; + if ((chanName[0] == 's') && (chanName[1] == 't')) { + chanPtr = NULL; + if (strcmp(chanName, "stdin") == 0) { + chanPtr = (Channel *)Tcl_GetStdChannel(TCL_STDIN); + } else if (strcmp(chanName, "stdout") == 0) { + chanPtr = (Channel *)Tcl_GetStdChannel(TCL_STDOUT); + } else if (strcmp(chanName, "stderr") == 0) { + chanPtr = (Channel *)Tcl_GetStdChannel(TCL_STDERR); + } + if (chanPtr != NULL) { + name = chanPtr->channelName; + } + } + + hTblPtr = GetChannelTable(interp); + hPtr = Tcl_FindHashEntry(hTblPtr, name); + if (hPtr == (Tcl_HashEntry *) NULL) { + Tcl_AppendResult(interp, "can not find channel named \"", + chanName, "\"", (char *) NULL); + return NULL; + } + + chanPtr = (Channel *) Tcl_GetHashValue(hPtr); + if (modePtr != NULL) { + *modePtr = (chanPtr->flags & (TCL_READABLE|TCL_WRITABLE)); + } + + return (Tcl_Channel) chanPtr; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_CreateChannel -- + * + * Creates a new entry in the hash table for a Tcl_Channel + * record. + * + * Results: + * Returns the new Tcl_Channel. + * + * Side effects: + * Creates a new Tcl_Channel instance and inserts it into the + * hash table. + * + *---------------------------------------------------------------------- + */ + +Tcl_Channel +Tcl_CreateChannel(typePtr, chanName, instanceData, mask) + Tcl_ChannelType *typePtr; /* The channel type record. */ + char *chanName; /* Name of channel to record. */ + ClientData instanceData; /* Instance specific data. */ + int mask; /* TCL_READABLE & TCL_WRITABLE to indicate + * if the channel is readable, writable. */ +{ + Channel *chanPtr; /* The channel structure newly created. */ + CONST char *name; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + chanPtr = (Channel *) ckalloc((unsigned) sizeof(Channel)); + + if (chanName != (char *) NULL) { + chanPtr->channelName = ckalloc((unsigned) (strlen(chanName) + 1)); + strcpy(chanPtr->channelName, chanName); + } else { + panic("Tcl_CreateChannel: NULL channel name"); + } + + chanPtr->flags = mask; + + /* + * Set the channel to system default encoding. + */ + + chanPtr->encoding = NULL; + name = Tcl_GetEncodingName(NULL); + if (strcmp(name, "binary") != 0) { + chanPtr->encoding = Tcl_GetEncoding(NULL, name); + } + chanPtr->inputEncodingState = NULL; + chanPtr->inputEncodingFlags = TCL_ENCODING_START; + chanPtr->outputEncodingState = NULL; + chanPtr->outputEncodingFlags = TCL_ENCODING_START; + + /* + * Set the channel up initially in AUTO input translation mode to + * accept "\n", "\r" and "\r\n". Output translation mode is set to + * a platform specific default value. The eofChar is set to 0 for both + * input and output, so that Tcl does not look for an in-file EOF + * indicator (e.g. ^Z) and does not append an EOF indicator to files. + */ + + chanPtr->inputTranslation = TCL_TRANSLATE_AUTO; + chanPtr->outputTranslation = TCL_PLATFORM_TRANSLATION; + chanPtr->inEofChar = 0; + chanPtr->outEofChar = 0; + + chanPtr->unreportedError = 0; + chanPtr->instanceData = instanceData; + chanPtr->typePtr = typePtr; + chanPtr->refCount = 0; + chanPtr->closeCbPtr = (CloseCallback *) NULL; + chanPtr->curOutPtr = (ChannelBuffer *) NULL; + chanPtr->outQueueHead = (ChannelBuffer *) NULL; + chanPtr->outQueueTail = (ChannelBuffer *) NULL; + chanPtr->saveInBufPtr = (ChannelBuffer *) NULL; + chanPtr->inQueueHead = (ChannelBuffer *) NULL; + chanPtr->inQueueTail = (ChannelBuffer *) NULL; + chanPtr->chPtr = (ChannelHandler *) NULL; + chanPtr->interestMask = 0; + chanPtr->scriptRecordPtr = (EventScriptRecord *) NULL; + chanPtr->bufSize = CHANNELBUFFER_DEFAULT_SIZE; + chanPtr->timer = NULL; + chanPtr->csPtr = NULL; + + chanPtr->outputStage = NULL; + if ((chanPtr->encoding != NULL) && (chanPtr->flags & TCL_WRITABLE)) { + chanPtr->outputStage = (char *) + ckalloc((unsigned) (chanPtr->bufSize + 2)); + } + + /* + * Link the channel into the list of all channels; create an on-exit + * handler if there is not one already, to close off all the channels + * in the list on exit. + */ + + chanPtr->nextChanPtr = tsdPtr->firstChanPtr; + tsdPtr->firstChanPtr = chanPtr; + + /* + * Install this channel in the first empty standard channel slot, if + * the channel was previously closed explicitly. + */ + + if ((tsdPtr->stdinChannel == NULL) && (tsdPtr->stdinInitialized == 1)) { + Tcl_SetStdChannel((Tcl_Channel)chanPtr, TCL_STDIN); + Tcl_RegisterChannel((Tcl_Interp *) NULL, (Tcl_Channel) chanPtr); + } else if ((tsdPtr->stdoutChannel == NULL) && (tsdPtr->stdoutInitialized == 1)) { + Tcl_SetStdChannel((Tcl_Channel)chanPtr, TCL_STDOUT); + Tcl_RegisterChannel((Tcl_Interp *) NULL, (Tcl_Channel) chanPtr); + } else if ((tsdPtr->stderrChannel == NULL) && (tsdPtr->stderrInitialized == 1)) { + Tcl_SetStdChannel((Tcl_Channel)chanPtr, TCL_STDERR); + Tcl_RegisterChannel((Tcl_Interp *) NULL, (Tcl_Channel) chanPtr); + } + return (Tcl_Channel) chanPtr; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetChannelMode -- + * + * Computes a mask indicating whether the channel is open for + * reading and writing. + * + * Results: + * An OR-ed combination of TCL_READABLE and TCL_WRITABLE. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_GetChannelMode(chan) + Tcl_Channel chan; /* The channel for which the mode is + * being computed. */ +{ + Channel *chanPtr; /* The actual channel. */ + + chanPtr = (Channel *) chan; + return (chanPtr->flags & (TCL_READABLE | TCL_WRITABLE)); +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetChannelName -- + * + * Returns the string identifying the channel name. + * + * Results: + * The string containing the channel name. This memory is + * owned by the generic layer and should not be modified by + * the caller. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +char * +Tcl_GetChannelName(chan) + Tcl_Channel chan; /* The channel for which to return the name. */ +{ + Channel *chanPtr; /* The actual channel. */ + + chanPtr = (Channel *) chan; + return chanPtr->channelName; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetChannelType -- + * + * Given a channel structure, returns the channel type structure. + * + * Results: + * Returns a pointer to the channel type structure. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +Tcl_ChannelType * +Tcl_GetChannelType(chan) + Tcl_Channel chan; /* The channel to return type for. */ +{ + Channel *chanPtr; /* The actual channel. */ + + chanPtr = (Channel *) chan; + return chanPtr->typePtr; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetChannelHandle -- + * + * Returns an OS handle associated with a channel. + * + * Results: + * Returns TCL_OK and places the handle in handlePtr, or returns + * TCL_ERROR on failure. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_GetChannelHandle(chan, direction, handlePtr) + Tcl_Channel chan; /* The channel to get file from. */ + int direction; /* TCL_WRITABLE or TCL_READABLE. */ + ClientData *handlePtr; /* Where to store handle */ +{ + Channel *chanPtr; /* The actual channel. */ + ClientData handle; + int result; + + chanPtr = (Channel *) chan; + result = (chanPtr->typePtr->getHandleProc)(chanPtr->instanceData, + direction, &handle); + if (handlePtr) { + *handlePtr = handle; + } + return result; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetChannelInstanceData -- + * + * Returns the client data associated with a channel. + * + * Results: + * The client data. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +ClientData +Tcl_GetChannelInstanceData(chan) + Tcl_Channel chan; /* Channel for which to return client data. */ +{ + Channel *chanPtr; /* The actual channel. */ + + chanPtr = (Channel *) chan; + return chanPtr->instanceData; +} + +/* + *--------------------------------------------------------------------------- + * + * AllocChannelBuffer -- + * + * A channel buffer has BUFFER_PADDING bytes extra at beginning to + * hold any bytes of a native-encoding character that got split by + * the end of the previous buffer and need to be moved to the + * beginning of the next buffer to make a contiguous string so it + * can be converted to UTF-8. + * + * A channel buffer has BUFFER_PADDING bytes extra at the end to + * hold any bytes of a native-encoding character (generated from a + * UTF-8 character) that overflow past the end of the buffer and + * need to be moved to the next buffer. + * + * Results: + * A newly allocated channel buffer. + * + * Side effects: + * None. + * + *--------------------------------------------------------------------------- + */ + +static ChannelBuffer * +AllocChannelBuffer(length) + int length; /* Desired length of channel buffer. */ +{ + ChannelBuffer *bufPtr; + int n; + + n = length + CHANNELBUFFER_HEADER_SIZE + BUFFER_PADDING + BUFFER_PADDING; + bufPtr = (ChannelBuffer *) ckalloc((unsigned) n); + bufPtr->nextAdded = BUFFER_PADDING; + bufPtr->nextRemoved = BUFFER_PADDING; + bufPtr->bufLength = length + BUFFER_PADDING; + bufPtr->nextPtr = (ChannelBuffer *) NULL; + return bufPtr; +} + +/* + *---------------------------------------------------------------------- + * + * RecycleBuffer -- + * + * Helper function to recycle input and output buffers. Ensures + * that two input buffers are saved (one in the input queue and + * another in the saveInBufPtr field) and that curOutPtr is set + * to a buffer. Only if these conditions are met is the buffer + * freed to the OS. + * + * Results: + * None. + * + * Side effects: + * May free a buffer to the OS. + * + *---------------------------------------------------------------------- + */ + +static void +RecycleBuffer(chanPtr, bufPtr, mustDiscard) + Channel *chanPtr; /* Channel for which to recycle buffers. */ + ChannelBuffer *bufPtr; /* The buffer to recycle. */ + int mustDiscard; /* If nonzero, free the buffer to the + * OS, always. */ +{ + /* + * Do we have to free the buffer to the OS? + */ + + if (mustDiscard) { + ckfree((char *) bufPtr); + return; + } + + /* + * Only save buffers for the input queue if the channel is readable. + */ + + if (chanPtr->flags & TCL_READABLE) { + if (chanPtr->inQueueHead == (ChannelBuffer *) NULL) { + chanPtr->inQueueHead = bufPtr; + chanPtr->inQueueTail = bufPtr; + goto keepit; + } + if (chanPtr->saveInBufPtr == (ChannelBuffer *) NULL) { + chanPtr->saveInBufPtr = bufPtr; + goto keepit; + } + } + + /* + * Only save buffers for the output queue if the channel is writable. + */ + + if (chanPtr->flags & TCL_WRITABLE) { + if (chanPtr->curOutPtr == (ChannelBuffer *) NULL) { + chanPtr->curOutPtr = bufPtr; + goto keepit; + } + } + + /* + * If we reached this code we return the buffer to the OS. + */ + + ckfree((char *) bufPtr); + return; + +keepit: + bufPtr->nextRemoved = BUFFER_PADDING; + bufPtr->nextAdded = BUFFER_PADDING; + bufPtr->nextPtr = (ChannelBuffer *) NULL; +} + +/* + *---------------------------------------------------------------------- + * + * DiscardOutputQueued -- + * + * Discards all output queued in the output queue of a channel. + * + * Results: + * None. + * + * Side effects: + * Recycles buffers. + * + *---------------------------------------------------------------------- + */ + +static void +DiscardOutputQueued(chanPtr) + Channel *chanPtr; /* The channel for which to discard output. */ +{ + ChannelBuffer *bufPtr; + + while (chanPtr->outQueueHead != (ChannelBuffer *) NULL) { + bufPtr = chanPtr->outQueueHead; + chanPtr->outQueueHead = bufPtr->nextPtr; + RecycleBuffer(chanPtr, bufPtr, 0); + } + chanPtr->outQueueHead = (ChannelBuffer *) NULL; + chanPtr->outQueueTail = (ChannelBuffer *) NULL; +} + +/* + *---------------------------------------------------------------------- + * + * CheckForDeadChannel -- + * + * This function checks is a given channel is Dead. + * (A channel that has been closed but not yet deallocated.) + * + * Results: + * True (1) if channel is Dead, False (0) if channel is Ok + * + * Side effects: + * None + * + *---------------------------------------------------------------------- + */ + +static int +CheckForDeadChannel(interp, chanPtr) + Tcl_Interp *interp; /* For error reporting (can be NULL) */ + Channel *chanPtr; /* The channel to check. */ +{ + if (chanPtr->flags & CHANNEL_DEAD) { + Tcl_SetErrno(EINVAL); + if (interp) { + Tcl_AppendResult(interp, + "unable to access channel: invalid channel", + (char *) NULL); + } + return 1; + } + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * FlushChannel -- + * + * This function flushes as much of the queued output as is possible + * now. If calledFromAsyncFlush is nonzero, it is being called in an + * event handler to flush channel output asynchronously. + * + * Results: + * 0 if successful, else the error code that was returned by the + * channel type operation. + * + * Side effects: + * May produce output on a channel. May block indefinitely if the + * channel is synchronous. May schedule an async flush on the channel. + * May recycle memory for buffers in the output queue. + * + *---------------------------------------------------------------------- + */ + +static int +FlushChannel(interp, chanPtr, calledFromAsyncFlush) + Tcl_Interp *interp; /* For error reporting during close. */ + Channel *chanPtr; /* The channel to flush on. */ + int calledFromAsyncFlush; /* If nonzero then we are being + * called from an asynchronous + * flush callback. */ +{ + ChannelBuffer *bufPtr; /* Iterates over buffered output + * queue. */ + int toWrite; /* Amount of output data in current + * buffer available to be written. */ + int written; /* Amount of output data actually + * written in current round. */ + int errorCode = 0; /* Stores POSIX error codes from + * channel driver operations. */ + int wroteSome = 0; /* Set to one if any data was + * written to the driver. */ + + /* + * Prevent writing on a dead channel -- a channel that has been closed + * but not yet deallocated. This can occur if the exit handler for the + * channel deallocation runs before all channels are deregistered in + * all interpreters. + */ + + if (CheckForDeadChannel(interp,chanPtr)) return -1; + + /* + * Loop over the queued buffers and attempt to flush as + * much as possible of the queued output to the channel. + */ + + while (1) { + + /* + * If the queue is empty and there is a ready current buffer, OR if + * the current buffer is full, then move the current buffer to the + * queue. + */ + + if (((chanPtr->curOutPtr != (ChannelBuffer *) NULL) && + (chanPtr->curOutPtr->nextAdded == chanPtr->curOutPtr->bufLength)) + || ((chanPtr->flags & BUFFER_READY) && + (chanPtr->outQueueHead == (ChannelBuffer *) NULL))) { + chanPtr->flags &= (~(BUFFER_READY)); + chanPtr->curOutPtr->nextPtr = (ChannelBuffer *) NULL; + if (chanPtr->outQueueHead == (ChannelBuffer *) NULL) { + chanPtr->outQueueHead = chanPtr->curOutPtr; + } else { + chanPtr->outQueueTail->nextPtr = chanPtr->curOutPtr; + } + chanPtr->outQueueTail = chanPtr->curOutPtr; + chanPtr->curOutPtr = (ChannelBuffer *) NULL; + } + bufPtr = chanPtr->outQueueHead; + + /* + * If we are not being called from an async flush and an async + * flush is active, we just return without producing any output. + */ + + if ((!calledFromAsyncFlush) && + (chanPtr->flags & BG_FLUSH_SCHEDULED)) { + return 0; + } + + /* + * If the output queue is still empty, break out of the while loop. + */ + + if (bufPtr == (ChannelBuffer *) NULL) { + break; /* Out of the "while (1)". */ + } + + /* + * Produce the output on the channel. + */ + + toWrite = bufPtr->nextAdded - bufPtr->nextRemoved; + written = (chanPtr->typePtr->outputProc) (chanPtr->instanceData, + (char *) bufPtr->buf + bufPtr->nextRemoved, toWrite, + &errorCode); + + /* + * If the write failed completely attempt to start the asynchronous + * flush mechanism and break out of this loop - do not attempt to + * write any more output at this time. + */ + + if (written < 0) { + + /* + * If the last attempt to write was interrupted, simply retry. + */ + + if (errorCode == EINTR) { + errorCode = 0; + continue; + } + + /* + * If the channel is non-blocking and we would have blocked, + * start a background flushing handler and break out of the loop. + */ + + if ((errorCode == EWOULDBLOCK) || (errorCode == EAGAIN)) { + if (chanPtr->flags & CHANNEL_NONBLOCKING) { + if (!(chanPtr->flags & BG_FLUSH_SCHEDULED)) { + chanPtr->flags |= BG_FLUSH_SCHEDULED; + UpdateInterest(chanPtr); + } + errorCode = 0; + break; + } else { + panic("Blocking channel driver did not block on output"); + } + } + + /* + * Decide whether to report the error upwards or defer it. + */ + + if (calledFromAsyncFlush) { + if (chanPtr->unreportedError == 0) { + chanPtr->unreportedError = errorCode; + } + } else { + Tcl_SetErrno(errorCode); + if (interp != NULL) { + Tcl_SetResult(interp, + Tcl_PosixError(interp), TCL_VOLATILE); + } + } + + /* + * When we get an error we throw away all the output + * currently queued. + */ + + DiscardOutputQueued(chanPtr); + continue; + } else { + wroteSome = 1; + } + + bufPtr->nextRemoved += written; + + /* + * If this buffer is now empty, recycle it. + */ + + if (bufPtr->nextRemoved == bufPtr->nextAdded) { + chanPtr->outQueueHead = bufPtr->nextPtr; + if (chanPtr->outQueueHead == (ChannelBuffer *) NULL) { + chanPtr->outQueueTail = (ChannelBuffer *) NULL; + } + RecycleBuffer(chanPtr, bufPtr, 0); + } + } /* Closes "while (1)". */ + + /* + * If we wrote some data while flushing in the background, we are done. + * We can't finish the background flush until we run out of data and + * the channel becomes writable again. This ensures that all of the + * pending data has been flushed at the system level. + */ + + if (chanPtr->flags & BG_FLUSH_SCHEDULED) { + if (wroteSome) { + return errorCode; + } else if (chanPtr->outQueueHead == (ChannelBuffer *) NULL) { + chanPtr->flags &= (~(BG_FLUSH_SCHEDULED)); + (chanPtr->typePtr->watchProc)(chanPtr->instanceData, + chanPtr->interestMask); + } + } + + /* + * If the channel is flagged as closed, delete it when the refCount + * drops to zero, the output queue is empty and there is no output + * in the current output buffer. + */ + + if ((chanPtr->flags & CHANNEL_CLOSED) && (chanPtr->refCount <= 0) && + (chanPtr->outQueueHead == (ChannelBuffer *) NULL) && + ((chanPtr->curOutPtr == (ChannelBuffer *) NULL) || + (chanPtr->curOutPtr->nextAdded == + chanPtr->curOutPtr->nextRemoved))) { + return CloseChannel(interp, chanPtr, errorCode); + } + return errorCode; +} + +/* + *---------------------------------------------------------------------- + * + * CloseChannel -- + * + * Utility procedure to close a channel and free its associated + * resources. + * + * Results: + * 0 on success or a POSIX error code if the operation failed. + * + * Side effects: + * May close the actual channel; may free memory. + * + *---------------------------------------------------------------------- + */ + +static int +CloseChannel(interp, chanPtr, errorCode) + Tcl_Interp *interp; /* For error reporting. */ + Channel *chanPtr; /* The channel to close. */ + int errorCode; /* Status of operation so far. */ +{ + int result = 0; /* Of calling driver close + * operation. */ + Channel *prevChanPtr; /* Preceding channel in list of + * all channels - used to splice a + * channel out of the list on close. */ + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + if (chanPtr == NULL) { + return result; + } + + /* + * No more input can be consumed so discard any leftover input. + */ + + DiscardInputQueued(chanPtr, 1); + + /* + * Discard a leftover buffer in the current output buffer field. + */ + + if (chanPtr->curOutPtr != (ChannelBuffer *) NULL) { + ckfree((char *) chanPtr->curOutPtr); + chanPtr->curOutPtr = (ChannelBuffer *) NULL; + } + + /* + * The caller guarantees that there are no more buffers + * queued for output. + */ + + if (chanPtr->outQueueHead != (ChannelBuffer *) NULL) { + panic("TclFlush, closed channel: queued output left"); + } + + /* + * If the EOF character is set in the channel, append that to the + * output device. + */ + + if ((chanPtr->outEofChar != 0) && (chanPtr->flags & TCL_WRITABLE)) { + int dummy; + char c; + + c = (char) chanPtr->outEofChar; + (chanPtr->typePtr->outputProc) (chanPtr->instanceData, &c, 1, &dummy); + } + + /* + * Remove TCL_READABLE and TCL_WRITABLE from chanPtr->flags, so + * that close callbacks can not do input or output (assuming they + * squirreled the channel away in their clientData). This also + * prevents infinite loops if the callback calls any C API that + * could call FlushChannel. + */ + + chanPtr->flags &= (~(TCL_READABLE|TCL_WRITABLE)); + + /* + * Splice this channel out of the list of all channels. + */ + + if (chanPtr == tsdPtr->firstChanPtr) { + tsdPtr->firstChanPtr = chanPtr->nextChanPtr; + } else { + for (prevChanPtr = tsdPtr->firstChanPtr; + (prevChanPtr != (Channel *) NULL) && + (prevChanPtr->nextChanPtr != chanPtr); + prevChanPtr = prevChanPtr->nextChanPtr) { + /* Empty loop body. */ + } + if (prevChanPtr == (Channel *) NULL) { + panic("FlushChannel: damaged channel list"); + } + prevChanPtr->nextChanPtr = chanPtr->nextChanPtr; + } + + /* + * Close and free the channel driver state. + */ + + if (chanPtr->typePtr->closeProc != TCL_CLOSE2PROC) { + result = (chanPtr->typePtr->closeProc)(chanPtr->instanceData, interp); + } else { + result = (chanPtr->typePtr->close2Proc)(chanPtr->instanceData, interp, + 0); + } + + if (chanPtr->channelName != (char *) NULL) { + ckfree(chanPtr->channelName); + } + Tcl_FreeEncoding(chanPtr->encoding); + if (chanPtr->outputStage != NULL) { + ckfree((char *) chanPtr->outputStage); + } + + /* + * If we are being called synchronously, report either + * any latent error on the channel or the current error. + */ + + if (chanPtr->unreportedError != 0) { + errorCode = chanPtr->unreportedError; + } + if (errorCode == 0) { + errorCode = result; + if (errorCode != 0) { + Tcl_SetErrno(errorCode); + } + } + + /* + * Cancel any outstanding timer. + */ + + Tcl_DeleteTimerHandler(chanPtr->timer); + + /* + * Mark the channel as deleted by clearing the type structure. + */ + + chanPtr->typePtr = NULL; + + Tcl_EventuallyFree((ClientData) chanPtr, TCL_DYNAMIC); + + return errorCode; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_Close -- + * + * Closes a channel. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * Closes the channel if this is the last reference. + * + * NOTE: + * Tcl_Close removes the channel as far as the user is concerned. + * However, it may continue to exist for a while longer if it has + * a background flush scheduled. The device itself is eventually + * closed and the channel record removed, in CloseChannel, above. + * + *---------------------------------------------------------------------- + */ + + /* ARGSUSED */ +int +Tcl_Close(interp, chan) + Tcl_Interp *interp; /* Interpreter for errors. */ + Tcl_Channel chan; /* The channel being closed. Must + * not be referenced in any + * interpreter. */ +{ + ChannelHandler *chPtr, *chNext; /* Iterate over channel handlers. */ + CloseCallback *cbPtr; /* Iterate over close callbacks + * for this channel. */ + EventScriptRecord *ePtr, *eNextPtr; /* Iterate over eventscript records. */ + Channel *chanPtr; /* The real IO channel. */ + int result; /* Of calling FlushChannel. */ + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + NextChannelHandler *nhPtr; + + if (chan == (Tcl_Channel) NULL) { + return TCL_OK; + } + + /* + * Perform special handling for standard channels being closed. If the + * refCount is now 1 it means that the last reference to the standard + * channel is being explicitly closed, so bump the refCount down + * artificially to 0. This will ensure that the channel is actually + * closed, below. Also set the static pointer to NULL for the channel. + */ + + CheckForStdChannelsBeingClosed(chan); + + chanPtr = (Channel *) chan; + if (chanPtr->refCount > 0) { + panic("called Tcl_Close on channel with refCount > 0"); + } + + /* + * Remove any references to channel handlers for this channel that + * may be about to be invoked. + */ + + for (nhPtr = tsdPtr->nestedHandlerPtr; + nhPtr != (NextChannelHandler *) NULL; + nhPtr = nhPtr->nestedHandlerPtr) { + if (nhPtr->nextHandlerPtr && + (nhPtr->nextHandlerPtr->chanPtr == chanPtr)) { + nhPtr->nextHandlerPtr = NULL; + } + } + + /* + * Remove all the channel handler records attached to the channel + * itself. + */ + + for (chPtr = chanPtr->chPtr; + chPtr != (ChannelHandler *) NULL; + chPtr = chNext) { + chNext = chPtr->nextPtr; + ckfree((char *) chPtr); + } + chanPtr->chPtr = (ChannelHandler *) NULL; + + + /* + * Cancel any pending copy operation. + */ + + StopCopy(chanPtr->csPtr); + + /* + * Must set the interest mask now to 0, otherwise infinite loops + * will occur if Tcl_DoOneEvent is called before the channel is + * finally deleted in FlushChannel. This can happen if the channel + * has a background flush active. + */ + + chanPtr->interestMask = 0; + + /* + * Remove any EventScript records for this channel. + */ + + for (ePtr = chanPtr->scriptRecordPtr; + ePtr != (EventScriptRecord *) NULL; + ePtr = eNextPtr) { + eNextPtr = ePtr->nextPtr; + Tcl_DecrRefCount(ePtr->scriptPtr); + ckfree((char *) ePtr); + } + chanPtr->scriptRecordPtr = (EventScriptRecord *) NULL; + + /* + * Invoke the registered close callbacks and delete their records. + */ + + while (chanPtr->closeCbPtr != (CloseCallback *) NULL) { + cbPtr = chanPtr->closeCbPtr; + chanPtr->closeCbPtr = cbPtr->nextPtr; + (cbPtr->proc) (cbPtr->clientData); + ckfree((char *) cbPtr); + } + + /* + * Ensure that the last output buffer will be flushed. + */ + + if ((chanPtr->curOutPtr != (ChannelBuffer *) NULL) && + (chanPtr->curOutPtr->nextAdded > chanPtr->curOutPtr->nextRemoved)) { + chanPtr->flags |= BUFFER_READY; + } + + /* + * If this channel supports it, close the read side, since we don't need it + * anymore and this will help avoid deadlocks on some channel types. + */ + + if (chanPtr->typePtr->closeProc == TCL_CLOSE2PROC) { + result = (chanPtr->typePtr->close2Proc)(chanPtr->instanceData, interp, + TCL_CLOSE_READ); + } else { + result = 0; + } + + /* + * The call to FlushChannel will flush any queued output and invoke + * the close function of the channel driver, or it will set up the + * channel to be flushed and closed asynchronously. + */ + + chanPtr->flags |= CHANNEL_CLOSED; + if ((FlushChannel(interp, chanPtr, 0) != 0) || (result != 0)) { + return TCL_ERROR; + } + return TCL_OK; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_Write -- + * + * Puts a sequence of bytes into an output buffer, may queue the + * buffer for output if it gets full, and also remembers whether the + * current buffer is ready e.g. if it contains a newline and we are in + * line buffering mode. + * + * Results: + * The number of bytes written or -1 in case of error. If -1, + * Tcl_GetErrno will return the error code. + * + * Side effects: + * May buffer up output and may cause output to be produced on the + * channel. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_Write(chan, src, srcLen) + Tcl_Channel chan; /* The channel to buffer output for. */ + char *src; /* Data to queue in output buffer. */ + int srcLen; /* Length of data in bytes, or < 0 for + * strlen(). */ +{ + Channel *chanPtr; + + chanPtr = (Channel *) chan; + if (CheckChannelErrors(chanPtr, TCL_WRITABLE) != 0) { + return -1; + } + if (srcLen < 0) { + srcLen = strlen(src); + } + return DoWrite(chanPtr, src, srcLen); +} + +/* + *--------------------------------------------------------------------------- + * + * Tcl_WriteChars -- + * + * Takes a sequence of UTF-8 characters and converts them for output + * using the channel's current encoding, may queue the buffer for + * output if it gets full, and also remembers whether the current + * buffer is ready e.g. if it contains a newline and we are in + * line buffering mode. + * + * Results: + * The number of bytes written or -1 in case of error. If -1, + * Tcl_GetErrno will return the error code. + * + * Side effects: + * May buffer up output and may cause output to be produced on the + * channel. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_WriteChars(chan, src, len) + Tcl_Channel chan; /* The channel to buffer output for. */ + CONST char *src; /* UTF-8 characters to queue in output buffer. */ + int len; /* Length of string in bytes, or < 0 for + * strlen(). */ +{ + Channel *chanPtr; + + chanPtr = (Channel *) chan; + if (CheckChannelErrors(chanPtr, TCL_WRITABLE) != 0) { + return -1; + } + if (len < 0) { + len = strlen(src); + } + if (chanPtr->encoding == NULL) { + /* + * Inefficient way to convert UTF-8 to byte-array, but the + * code parallels the way it is done for objects. + */ + + Tcl_Obj *objPtr; + int result; + + objPtr = Tcl_NewStringObj(src, len); + src = (char *) Tcl_GetByteArrayFromObj(objPtr, &len); + result = WriteBytes(chanPtr, src, len); + Tcl_DecrRefCount(objPtr); + return result; + } + return WriteChars(chanPtr, src, len); +} + +/* + *--------------------------------------------------------------------------- + * + * Tcl_WriteObj -- + * + * Takes the Tcl object and queues its contents for output. If the + * encoding of the channel is NULL, takes the byte-array representation + * of the object and queues those bytes for output. Otherwise, takes + * the characters in the UTF-8 (string) representation of the object + * and converts them for output using the channel's current encoding. + * May flush internal buffers to output if one becomes full or is ready + * for some other reason, e.g. if it contains a newline and the channel + * is in line buffering mode. + * + * Results: + * The number of bytes written or -1 in case of error. If -1, + * Tcl_GetErrno() will return the error code. + * + * Side effects: + * May buffer up output and may cause output to be produced on the + * channel. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_WriteObj(chan, objPtr) + Tcl_Channel chan; /* The channel to buffer output for. */ + Tcl_Obj *objPtr; /* The object to write. */ +{ + Channel *chanPtr; + char *src; + int srcLen; + + chanPtr = (Channel *) chan; + if (CheckChannelErrors(chanPtr, TCL_WRITABLE) != 0) { + return -1; + } + if (chanPtr->encoding == NULL) { + src = (char *) Tcl_GetByteArrayFromObj(objPtr, &srcLen); + return WriteBytes(chanPtr, src, srcLen); + } else { + src = Tcl_GetStringFromObj(objPtr, &srcLen); + return WriteChars(chanPtr, src, srcLen); + } +} + +/* + *---------------------------------------------------------------------- + * + * WriteBytes -- + * + * Write a sequence of bytes into an output buffer, may queue the + * buffer for output if it gets full, and also remembers whether the + * current buffer is ready e.g. if it contains a newline and we are in + * line buffering mode. + * + * Results: + * The number of bytes written or -1 in case of error. If -1, + * Tcl_GetErrno will return the error code. + * + * Side effects: + * May buffer up output and may cause output to be produced on the + * channel. + * + *---------------------------------------------------------------------- + */ + +static int +WriteBytes(chanPtr, src, srcLen) + Channel *chanPtr; /* The channel to buffer output for. */ + CONST char *src; /* Bytes to write. */ + int srcLen; /* Number of bytes to write. */ +{ + ChannelBuffer *bufPtr; + char *dst; + int dstLen, dstMax, sawLF, savedLF, total, toWrite; + + total = 0; + sawLF = 0; + savedLF = 0; + + /* + * Loop over all bytes in src, storing them in output buffer with + * proper EOL translation. + */ + + while (srcLen + savedLF > 0) { + bufPtr = chanPtr->curOutPtr; + if (bufPtr == NULL) { + bufPtr = AllocChannelBuffer(chanPtr->bufSize); + chanPtr->curOutPtr = bufPtr; + } + dst = bufPtr->buf + bufPtr->nextAdded; + dstMax = bufPtr->bufLength - bufPtr->nextAdded; + dstLen = dstMax; + + toWrite = dstLen; + if (toWrite > srcLen) { + toWrite = srcLen; + } + + if (savedLF) { + /* + * A '\n' was left over from last call to TranslateOutputEOL() + * and we need to store it in this buffer. If the channel is + * line-based, we will need to flush it. + */ + + *dst++ = '\n'; + dstLen--; + sawLF++; + } + sawLF += TranslateOutputEOL(chanPtr, dst, src, &dstLen, &toWrite); + dstLen += savedLF; + savedLF = 0; + + if (dstLen > dstMax) { + savedLF = 1; + dstLen = dstMax; + } + bufPtr->nextAdded += dstLen; + if (CheckFlush(chanPtr, bufPtr, sawLF) != 0) { + return -1; + } + total += dstLen; + src += toWrite; + srcLen -= toWrite; + sawLF = 0; + } + return total; +} + +/* + *---------------------------------------------------------------------- + * + * WriteChars -- + * + * Convert UTF-8 bytes to the channel's external encoding and + * write the produced bytes into an output buffer, may queue the + * buffer for output if it gets full, and also remembers whether the + * current buffer is ready e.g. if it contains a newline and we are in + * line buffering mode. + * + * Results: + * The number of bytes written or -1 in case of error. If -1, + * Tcl_GetErrno will return the error code. + * + * Side effects: + * May buffer up output and may cause output to be produced on the + * channel. + * + *---------------------------------------------------------------------- + */ + +static int +WriteChars(chanPtr, src, srcLen) + Channel *chanPtr; /* The channel to buffer output for. */ + CONST char *src; /* UTF-8 string to write. */ + int srcLen; /* Length of UTF-8 string in bytes. */ +{ + ChannelBuffer *bufPtr; + char *dst, *stage; + int saved, savedLF, sawLF, total, toWrite, flags; + int dstWrote, dstLen, stageLen, stageMax, stageRead; + Tcl_Encoding encoding; + char safe[BUFFER_PADDING]; + + total = 0; + sawLF = 0; + savedLF = 0; + saved = 0; + encoding = chanPtr->encoding; + + /* + * Loop over all UTF-8 characters in src, storing them in staging buffer + * with proper EOL translation. + */ + + while (srcLen + savedLF > 0) { + stage = chanPtr->outputStage; + stageMax = chanPtr->bufSize; + stageLen = stageMax; + + toWrite = stageLen; + if (toWrite > srcLen) { + toWrite = srcLen; + } + + if (savedLF) { + /* + * A '\n' was left over from last call to TranslateOutputEOL() + * and we need to store it in the staging buffer. If the + * channel is line-based, we will need to flush the output + * buffer (after translating the staging buffer). + */ + + *stage++ = '\n'; + stageLen--; + sawLF++; + } + sawLF += TranslateOutputEOL(chanPtr, stage, src, &stageLen, &toWrite); + + stage -= savedLF; + stageLen += savedLF; + savedLF = 0; + + if (stageLen > stageMax) { + savedLF = 1; + stageLen = stageMax; + } + src += toWrite; + srcLen -= toWrite; + + flags = chanPtr->outputEncodingFlags; + if (srcLen == 0) { + flags |= TCL_ENCODING_END; + } + + /* + * Loop over all UTF-8 characters in staging buffer, converting them + * to external encoding, storing them in output buffer. + */ + + while (stageLen + saved > 0) { + bufPtr = chanPtr->curOutPtr; + if (bufPtr == NULL) { + bufPtr = AllocChannelBuffer(chanPtr->bufSize); + chanPtr->curOutPtr = bufPtr; + } + dst = bufPtr->buf + bufPtr->nextAdded; + dstLen = bufPtr->bufLength - bufPtr->nextAdded; + + if (saved != 0) { + /* + * Here's some translated bytes left over from the last + * buffer that we need to stick at the beginning of this + * buffer. + */ + + memcpy((VOID *) dst, (VOID *) safe, (size_t) saved); + bufPtr->nextAdded += saved; + dst += saved; + dstLen -= saved; + saved = 0; + } + + Tcl_UtfToExternal(NULL, encoding, stage, stageLen, flags, + &chanPtr->outputEncodingState, dst, + dstLen + BUFFER_PADDING, &stageRead, &dstWrote, NULL); + if (stageRead + dstWrote == 0) { + /* + * We have an incomplete UTF-8 character at the end of the + * staging buffer. It will get moved to the beginning of the + * staging buffer followed by more bytes from src. + */ + + src -= stageLen; + srcLen += stageLen; + stageLen = 0; + savedLF = 0; + break; + } + bufPtr->nextAdded += dstWrote; + if (bufPtr->nextAdded > bufPtr->bufLength) { + /* + * When translating from UTF-8 to external encoding, we + * allowed the translation to produce a character that + * crossed the end of the output buffer, so that we would + * get a completely full buffer before flushing it. The + * extra bytes will be moved to the beginning of the next + * buffer. + */ + + saved = bufPtr->nextAdded - bufPtr->bufLength; + memcpy((VOID *) safe, (VOID *) (dst + dstLen), (size_t) saved); + bufPtr->nextAdded = bufPtr->bufLength; + } + if (CheckFlush(chanPtr, bufPtr, sawLF) != 0) { + return -1; + } + + total += dstWrote; + stage += stageRead; + stageLen -= stageRead; + sawLF = 0; + } + } + return total; +} + +/* + *--------------------------------------------------------------------------- + * + * TranslateOutputEOL -- + * + * Helper function for WriteBytes() and WriteChars(). Converts the + * '\n' characters in the source buffer into the appropriate EOL + * form specified by the output translation mode. + * + * EOL translation stops either when the source buffer is empty + * or the output buffer is full. + * + * When converting to CRLF mode and there is only 1 byte left in + * the output buffer, this routine stores the '\r' in the last + * byte and then stores the '\n' in the byte just past the end of the + * buffer. The caller is responsible for passing in a buffer that + * is large enough to hold the extra byte. + * + * Results: + * The return value is 1 if a '\n' was translated from the source + * buffer, or 0 otherwise -- this can be used by the caller to + * decide to flush a line-based channel even though the channel + * buffer is not full. + * + * *dstLenPtr is filled with how many bytes of the output buffer + * were used. As mentioned above, this can be one more that + * the output buffer's specified length if a CRLF was stored. + * + * *srcLenPtr is filled with how many bytes of the source buffer + * were consumed. + * + * Side effects: + * It may be obvious, but bears mentioning that when converting + * in CRLF mode (which requires two bytes of storage in the output + * buffer), the number of bytes consumed from the source buffer + * will be less than the number of bytes stored in the output buffer. + * + *--------------------------------------------------------------------------- + */ + +static int +TranslateOutputEOL(chanPtr, dst, src, dstLenPtr, srcLenPtr) + Channel *chanPtr; /* Channel being read, for translation and + * buffering modes. */ + char *dst; /* Output buffer filled with UTF-8 chars by + * applying appropriate EOL translation to + * source characters. */ + CONST char *src; /* Source UTF-8 characters. */ + int *dstLenPtr; /* On entry, the maximum length of output + * buffer in bytes. On exit, the number of + * bytes actually used in output buffer. */ + int *srcLenPtr; /* On entry, the length of source buffer. + * On exit, the number of bytes read from + * the source buffer. */ +{ + char *dstEnd; + int srcLen, newlineFound; + + newlineFound = 0; + srcLen = *srcLenPtr; + + switch (chanPtr->outputTranslation) { + case TCL_TRANSLATE_LF: { + for (dstEnd = dst + srcLen; dst < dstEnd; ) { + if (*src == '\n') { + newlineFound = 1; + } + *dst++ = *src++; + } + *dstLenPtr = srcLen; + break; + } + case TCL_TRANSLATE_CR: { + for (dstEnd = dst + srcLen; dst < dstEnd;) { + if (*src == '\n') { + *dst++ = '\r'; + newlineFound = 1; + src++; + } else { + *dst++ = *src++; + } + } + *dstLenPtr = srcLen; + break; + } + case TCL_TRANSLATE_CRLF: { + /* + * Since this causes the number of bytes to grow, we + * start off trying to put 'srcLen' bytes into the + * output buffer, but allow it to store more bytes, as + * long as there's still source bytes and room in the + * output buffer. + */ + + char *dstStart, *dstMax; + CONST char *srcStart; + + dstStart = dst; + dstMax = dst + *dstLenPtr; + + srcStart = src; + + if (srcLen < *dstLenPtr) { + dstEnd = dst + srcLen; + } else { + dstEnd = dst + *dstLenPtr; + } + while (dst < dstEnd) { + if (*src == '\n') { + if (dstEnd < dstMax) { + dstEnd++; + } + *dst++ = '\r'; + newlineFound = 1; + } + *dst++ = *src++; + } + *srcLenPtr = src - srcStart; + *dstLenPtr = dst - dstStart; + break; + } + default: { + break; + } + } + return newlineFound; +} + +/* + *--------------------------------------------------------------------------- + * + * CheckFlush -- + * + * Helper function for WriteBytes() and WriteChars(). If the + * channel buffer is ready to be flushed, flush it. + * + * Results: + * The return value is -1 if there was a problem flushing the + * channel buffer, or 0 otherwise. + * + * Side effects: + * The buffer will be recycled if it is flushed. + * + *--------------------------------------------------------------------------- + */ + +static int +CheckFlush(chanPtr, bufPtr, newlineFlag) + Channel *chanPtr; /* Channel being read, for buffering mode. */ + ChannelBuffer *bufPtr; /* Channel buffer to possibly flush. */ + int newlineFlag; /* Non-zero if a the channel buffer + * contains a newline. */ +{ + /* + * The current buffer is ready for output: + * 1. if it is full. + * 2. if it contains a newline and this channel is line-buffered. + * 3. if it contains any output and this channel is unbuffered. + */ + + if ((chanPtr->flags & BUFFER_READY) == 0) { + if (bufPtr->nextAdded == bufPtr->bufLength) { + chanPtr->flags |= BUFFER_READY; + } else if (chanPtr->flags & CHANNEL_LINEBUFFERED) { + if (newlineFlag != 0) { + chanPtr->flags |= BUFFER_READY; + } + } else if (chanPtr->flags & CHANNEL_UNBUFFERED) { + chanPtr->flags |= BUFFER_READY; + } + } + if (chanPtr->flags & BUFFER_READY) { + if (FlushChannel(NULL, chanPtr, 0) != 0) { + return -1; + } + } + return 0; +} + +/* + *--------------------------------------------------------------------------- + * + * Tcl_Gets -- + * + * Reads a complete line of input from the channel into a Tcl_DString. + * + * Results: + * Length of line read (in characters) or -1 if error, EOF, or blocked. + * If -1, use Tcl_GetErrno() to retrieve the POSIX error code for the + * error or condition that occurred. + * + * Side effects: + * May flush output on the channel. May cause input to be consumed + * from the channel. + * + *--------------------------------------------------------------------------- + */ + +int +Tcl_Gets(chan, lineRead) + Tcl_Channel chan; /* Channel from which to read. */ + Tcl_DString *lineRead; /* The line read will be appended to this + * DString as UTF-8 characters. The caller + * must have initialized it and is responsible + * for managing the storage. */ +{ + Tcl_Obj *objPtr; + int charsStored, length; + char *string; + + objPtr = Tcl_NewObj(); + charsStored = Tcl_GetsObj(chan, objPtr); + if (charsStored > 0) { + string = Tcl_GetStringFromObj(objPtr, &length); + Tcl_DStringAppend(lineRead, string, length); + } + Tcl_DecrRefCount(objPtr); + return charsStored; +} + +/* + *--------------------------------------------------------------------------- + * + * Tcl_GetsObj -- + * + * Accumulate input from the input channel until end-of-line or + * end-of-file has been seen. Bytes read from the input channel + * are converted to UTF-8 using the encoding specified by the + * channel. + * + * Results: + * Number of characters accumulated in the object or -1 if error, + * blocked, or EOF. If -1, use Tcl_GetErrno() to retrieve the + * POSIX error code for the error or condition that occurred. + * + * Side effects: + * Consumes input from the channel. + * + * On reading EOF, leave channel pointing at EOF char. + * On reading EOL, leave channel pointing after EOL, but don't + * return EOL in dst buffer. + * + *--------------------------------------------------------------------------- + */ + +int +Tcl_GetsObj(chan, objPtr) + Tcl_Channel chan; /* Channel from which to read. */ + Tcl_Obj *objPtr; /* The line read will be appended to this + * object as UTF-8 characters. */ +{ + GetsState gs; + Channel *chanPtr; + int inEofChar, skip, copiedTotal; + ChannelBuffer *bufPtr; + Tcl_Encoding encoding; + char *dst, *dstEnd, *eol, *eof; + Tcl_EncodingState oldState; + int oldLength, oldFlags, oldRemoved; + + chanPtr = (Channel *) chan; + if (CheckChannelErrors(chanPtr, TCL_READABLE) != 0) { + copiedTotal = -1; + goto done; + } + + bufPtr = chanPtr->inQueueHead; + encoding = chanPtr->encoding; + + /* + * Preserved so we can restore the channel's state in case we don't + * find a newline in the available input. + */ + + Tcl_GetStringFromObj(objPtr, &oldLength); + oldFlags = chanPtr->inputEncodingFlags; + oldState = chanPtr->inputEncodingState; + oldRemoved = BUFFER_PADDING; + if (bufPtr != NULL) { + oldRemoved = bufPtr->nextRemoved; + } + + /* + * If there is no encoding, use "iso8859-1" -- Tcl_GetsObj() doesn't + * produce ByteArray objects. To avoid circularity problems, + * "iso8859-1" is builtin to Tcl. + */ + + if (encoding == NULL) { + encoding = Tcl_GetEncoding(NULL, "iso8859-1"); + } + + /* + * Object used by FilterInputBytes to keep track of how much data has + * been consumed from the channel buffers. + */ + + gs.objPtr = objPtr; + gs.dstPtr = &dst; + gs.encoding = encoding; + gs.bufPtr = bufPtr; + gs.state = oldState; + gs.rawRead = 0; + gs.bytesWrote = 0; + gs.charsWrote = 0; + gs.totalChars = 0; + + dst = objPtr->bytes + oldLength; + dstEnd = dst; + + skip = 0; + eof = NULL; + inEofChar = chanPtr->inEofChar; + + while (1) { + if (dst >= dstEnd) { + if (FilterInputBytes(chanPtr, &gs) != 0) { + goto restore; + } + dstEnd = dst + gs.bytesWrote; + } + + /* + * Remember if EOF char is seen, then look for EOL anyhow, because + * the EOL might be before the EOF char. + */ + + if (inEofChar != '\0') { + for (eol = dst; eol < dstEnd; eol++) { + if (*eol == inEofChar) { + dstEnd = eol; + eof = eol; + break; + } + } + } + + /* + * On EOL, leave current file position pointing after the EOL, but + * don't store the EOL in the output string. + */ + + eol = dst; + switch (chanPtr->inputTranslation) { + case TCL_TRANSLATE_LF: { + for (eol = dst; eol < dstEnd; eol++) { + if (*eol == '\n') { + skip = 1; + goto goteol; + } + } + break; + } + case TCL_TRANSLATE_CR: { + for (eol = dst; eol < dstEnd; eol++) { + if (*eol == '\r') { + skip = 1; + goto goteol; + } + } + break; + } + case TCL_TRANSLATE_CRLF: { + for (eol = dst; eol < dstEnd; eol++) { + if (*eol == '\r') { + eol++; + if (eol >= dstEnd) { + int offset; + + offset = eol - objPtr->bytes; + dst = dstEnd; + if (FilterInputBytes(chanPtr, &gs) != 0) { + goto restore; + } + dstEnd = dst + gs.bytesWrote; + eol = objPtr->bytes + offset; + if (eol >= dstEnd) { + skip = 0; + goto goteol; + } + } + if (*eol == '\n') { + eol--; + skip = 2; + goto goteol; + } + } + } + break; + } + case TCL_TRANSLATE_AUTO: { + skip = 1; + if (chanPtr->flags & INPUT_SAW_CR) { + chanPtr->flags &= ~INPUT_SAW_CR; + if (*eol == '\n') { + /* + * Skip the raw bytes that make up the '\n'. + */ + + char tmp[1 + TCL_UTF_MAX]; + int rawRead; + + bufPtr = gs.bufPtr; + Tcl_ExternalToUtf(NULL, gs.encoding, + bufPtr->buf + bufPtr->nextRemoved, + gs.rawRead, chanPtr->inputEncodingFlags, + &gs.state, tmp, 1 + TCL_UTF_MAX, &rawRead, + NULL, NULL); + bufPtr->nextRemoved += rawRead; + gs.rawRead -= rawRead; + gs.bytesWrote--; + gs.charsWrote--; + memmove(dst, dst + 1, (size_t) (dstEnd - dst)); + dstEnd--; + } + } + for (eol = dst; eol < dstEnd; eol++) { + if (*eol == '\r') { + eol++; + if (eol == dstEnd) { + /* + * If buffer ended on \r, peek ahead to see if a + * \n is available. + */ + + int offset; + + offset = eol - objPtr->bytes; + dst = dstEnd; + PeekAhead(chanPtr, &dstEnd, &gs); + eol = objPtr->bytes + offset; + if (eol >= dstEnd) { + eol--; + chanPtr->flags |= INPUT_SAW_CR; + goto goteol; + } + } + if (*eol == '\n') { + skip++; + } + eol--; + goto goteol; + } else if (*eol == '\n') { + goto goteol; + } + } + } + } + if (eof != NULL) { + /* + * EOF character was seen. On EOF, leave current file position + * pointing at the EOF character, but don't store the EOF + * character in the output string. + */ + + dstEnd = eof; + chanPtr->flags |= (CHANNEL_EOF | CHANNEL_STICKY_EOF); + chanPtr->inputEncodingFlags |= TCL_ENCODING_END; + } + if (chanPtr->flags & CHANNEL_EOF) { + skip = 0; + eol = dstEnd; + if (eol == objPtr->bytes) { + /* + * If we didn't produce any bytes before encountering EOF, + * caller needs to see -1. + */ + + Tcl_SetObjLength(objPtr, 0); + CommonGetsCleanup(chanPtr, encoding); + copiedTotal = -1; + goto done; + } + goto goteol; + } + dst = dstEnd; + } + + /* + * Found EOL or EOF, but the output buffer may now contain too many + * UTF-8 characters. We need to know how many raw bytes correspond to + * the number of UTF-8 characters we want, plus how many raw bytes + * correspond to the character(s) making up EOL (if any), so we can + * remove the correct number of bytes from the channel buffer. + */ + + goteol: + bufPtr = gs.bufPtr; + chanPtr->inputEncodingState = gs.state; + Tcl_ExternalToUtf(NULL, gs.encoding, bufPtr->buf + bufPtr->nextRemoved, + gs.rawRead, chanPtr->inputEncodingFlags, + &chanPtr->inputEncodingState, dst, eol - dst + skip + TCL_UTF_MAX, + &gs.rawRead, NULL, &gs.charsWrote); + bufPtr->nextRemoved += gs.rawRead; + + /* + * Recycle all the emptied buffers. + */ + + Tcl_SetObjLength(objPtr, eol - objPtr->bytes); + CommonGetsCleanup(chanPtr, encoding); + chanPtr->flags &= ~CHANNEL_BLOCKED; + copiedTotal = gs.totalChars + gs.charsWrote - skip; + goto done; + + /* + * Couldn't get a complete line. This only happens if we get a error + * reading from the channel or we are non-blocking and there wasn't + * an EOL or EOF in the data available. + */ + + restore: + bufPtr = chanPtr->inQueueHead; + bufPtr->nextRemoved = oldRemoved; + + for (bufPtr = bufPtr->nextPtr; bufPtr != NULL; bufPtr = bufPtr->nextPtr) { + bufPtr->nextRemoved = BUFFER_PADDING; + } + CommonGetsCleanup(chanPtr, encoding); + + chanPtr->inputEncodingState = oldState; + chanPtr->inputEncodingFlags = oldFlags; + Tcl_SetObjLength(objPtr, oldLength); + + /* + * We didn't get a complete line so we need to indicate to UpdateInterest + * that the gets blocked. It will wait for more data instead of firing + * a timer, avoiding a busy wait. This is where we are assuming that the + * next operation is a gets. No more file events will be delivered on + * this channel until new data arrives or some operation is performed + * on the channel (e.g. gets, read, fconfigure) that changes the blocking + * state. Note that this means a file event will not be delivered even + * though a read would be able to consume the buffered data. + */ + + chanPtr->flags |= CHANNEL_NEED_MORE_DATA; + copiedTotal = -1; + + done: + /* + * Update the notifier state so we don't block while there is still + * data in the buffers. + */ + + UpdateInterest(chanPtr); + return copiedTotal; +} + +/* + *--------------------------------------------------------------------------- + * + * FilterInputBytes -- + * + * Helper function for Tcl_GetsObj. Produces UTF-8 characters from + * raw bytes read from the channel. + * + * Consumes available bytes from channel buffers. When channel + * buffers are exhausted, reads more bytes from channel device into + * a new channel buffer. It is the caller's responsibility to + * free the channel buffers that have been exhausted. + * + * Results: + * The return value is -1 if there was an error reading from the + * channel, 0 otherwise. + * + * Side effects: + * Status object keeps track of how much data from channel buffers + * has been consumed and where UTF-8 bytes should be stored. + * + *--------------------------------------------------------------------------- + */ + +static int +FilterInputBytes(chanPtr, gsPtr) + Channel *chanPtr; /* Channel to read. */ + GetsState *gsPtr; /* Current state of gets operation. */ +{ + ChannelBuffer *bufPtr; + char *raw, *rawStart, *rawEnd; + char *dst; + int offset, toRead, dstNeeded, spaceLeft, result, rawLen, length; + Tcl_Obj *objPtr; +#define ENCODING_LINESIZE 30 /* Lower bound on how many bytes to convert + * at a time. Since we don't know a priori + * how many bytes of storage this many source + * bytes will use, we actually need at least + * ENCODING_LINESIZE * TCL_MAX_UTF bytes of + * room. */ + + objPtr = gsPtr->objPtr; + + /* + * Subtract the number of bytes that were removed from channel buffer + * during last call. + */ + + bufPtr = gsPtr->bufPtr; + if (bufPtr != NULL) { + bufPtr->nextRemoved += gsPtr->rawRead; + if (bufPtr->nextRemoved >= bufPtr->nextAdded) { + bufPtr = bufPtr->nextPtr; + } + } + gsPtr->totalChars += gsPtr->charsWrote; + + if ((bufPtr == NULL) || (bufPtr->nextAdded == BUFFER_PADDING)) { + /* + * All channel buffers were exhausted and the caller still hasn't + * seen EOL. Need to read more bytes from the channel device. + * Side effect is to allocate another channel buffer. + */ + + read: + if (chanPtr->flags & CHANNEL_BLOCKED) { + if (chanPtr->flags & CHANNEL_NONBLOCKING) { + gsPtr->charsWrote = 0; + gsPtr->rawRead = 0; + return -1; + } + chanPtr->flags &= ~CHANNEL_BLOCKED; + } + if (GetInput(chanPtr) != 0) { + gsPtr->charsWrote = 0; + gsPtr->rawRead = 0; + return -1; + } + bufPtr = chanPtr->inQueueTail; + gsPtr->bufPtr = bufPtr; + } + + /* + * Convert some of the bytes from the channel buffer to UTF-8. Space in + * objPtr's string rep is used to hold the UTF-8 characters. Grow the + * string rep if we need more space. + */ + + rawStart = bufPtr->buf + bufPtr->nextRemoved; + raw = rawStart; + rawEnd = bufPtr->buf + bufPtr->nextAdded; + rawLen = rawEnd - rawStart; + + dst = *gsPtr->dstPtr; + offset = dst - objPtr->bytes; + toRead = ENCODING_LINESIZE; + if (toRead > rawLen) { + toRead = rawLen; + } + dstNeeded = toRead * TCL_UTF_MAX + 1; + spaceLeft = objPtr->length - offset - TCL_UTF_MAX - 1; + if (dstNeeded > spaceLeft) { + length = offset * 2; + if (offset < dstNeeded) { + length = offset + dstNeeded; + } + length += TCL_UTF_MAX + 1; + Tcl_SetObjLength(objPtr, length); + spaceLeft = length - offset; + dst = objPtr->bytes + offset; + *gsPtr->dstPtr = dst; + } + gsPtr->state = chanPtr->inputEncodingState; + result = Tcl_ExternalToUtf(NULL, gsPtr->encoding, raw, rawLen, + chanPtr->inputEncodingFlags, &chanPtr->inputEncodingState, + dst, spaceLeft, &gsPtr->rawRead, &gsPtr->bytesWrote, + &gsPtr->charsWrote); + if (result == TCL_CONVERT_MULTIBYTE) { + /* + * The last few bytes in this channel buffer were the start of a + * multibyte sequence. If this buffer was full, then move them to + * the next buffer so the bytes will be contiguous. + */ + + ChannelBuffer *nextPtr; + int extra; + + nextPtr = bufPtr->nextPtr; + if (bufPtr->nextAdded < bufPtr->bufLength) { + if (gsPtr->rawRead > 0) { + /* + * Some raw bytes were converted to UTF-8. Fall through, + * returning those UTF-8 characters because a EOL might be + * present in them. + */ + } else if (chanPtr->flags & CHANNEL_EOF) { + /* + * There was a partial character followed by EOF on the + * device. Fall through, returning that nothing was found. + */ + + bufPtr->nextRemoved = bufPtr->nextAdded; + } else { + /* + * There are no more cached raw bytes left. See if we can + * get some more. + */ + + goto read; + } + } else { + if (nextPtr == NULL) { + nextPtr = AllocChannelBuffer(chanPtr->bufSize); + bufPtr->nextPtr = nextPtr; + chanPtr->inQueueTail = nextPtr; + } + extra = rawLen - gsPtr->rawRead; + memcpy((VOID *) (nextPtr->buf + BUFFER_PADDING - extra), + (VOID *) (raw + gsPtr->rawRead), (size_t) extra); + nextPtr->nextRemoved -= extra; + bufPtr->nextAdded -= extra; + } + } + + gsPtr->bufPtr = bufPtr; + return 0; +} + +/* + *--------------------------------------------------------------------------- + * + * PeekAhead -- + * + * Helper function used by Tcl_GetsObj(). Called when we've seen a + * \r at the end of the UTF-8 string and want to look ahead one + * character to see if it is a \n. + * + * Results: + * *gsPtr->dstPtr is filled with a pointer to the start of the range of + * UTF-8 characters that were found by peeking and *dstEndPtr is filled + * with a pointer to the bytes just after the end of the range. + * + * Side effects: + * If no more raw bytes were available in one of the channel buffers, + * tries to perform a non-blocking read to get more bytes from the + * channel device. + * + *--------------------------------------------------------------------------- + */ + +static void +PeekAhead(chanPtr, dstEndPtr, gsPtr) + Channel *chanPtr; /* The channel to read. */ + char **dstEndPtr; /* Filled with pointer to end of new range + * of UTF-8 characters. */ + GetsState *gsPtr; /* Current state of gets operation. */ +{ + ChannelBuffer *bufPtr; + Tcl_DriverBlockModeProc *blockModeProc; + int bytesLeft; + + bufPtr = gsPtr->bufPtr; + + /* + * If there's any more raw input that's still buffered, we'll peek into + * that. Otherwise, only get more data from the channel driver if it + * looks like there might actually be more data. The assumption is that + * if the channel buffer is filled right up to the end, then there + * might be more data to read. + */ + + blockModeProc = NULL; + if (bufPtr->nextPtr == NULL) { + bytesLeft = bufPtr->nextAdded - (bufPtr->nextRemoved + gsPtr->rawRead); + if (bytesLeft == 0) { + if (bufPtr->nextAdded < bufPtr->bufLength) { + /* + * Don't peek ahead if last read was short read. + */ + + goto cleanup; + } + if ((chanPtr->flags & CHANNEL_NONBLOCKING) == 0) { + blockModeProc = chanPtr->typePtr->blockModeProc; + if (blockModeProc == NULL) { + /* + * Don't peek ahead if cannot set non-blocking mode. + */ + + goto cleanup; + } + (*blockModeProc)(chanPtr->instanceData, TCL_MODE_NONBLOCKING); + } + } + } + if (FilterInputBytes(chanPtr, gsPtr) == 0) { + *dstEndPtr = *gsPtr->dstPtr + gsPtr->bytesWrote; + } + if (blockModeProc != NULL) { + (*blockModeProc)(chanPtr->instanceData, TCL_MODE_BLOCKING); + } + return; + + cleanup: + bufPtr->nextRemoved += gsPtr->rawRead; + gsPtr->rawRead = 0; + gsPtr->totalChars += gsPtr->charsWrote; + gsPtr->bytesWrote = 0; + gsPtr->charsWrote = 0; +} + +/* + *--------------------------------------------------------------------------- + * + * CommonGetsCleanup -- + * + * Helper function for Tcl_GetsObj() to restore the channel after + * a "gets" operation. + * + * Results: + * None. + * + * Side effects: + * Encoding may be freed. + * + *--------------------------------------------------------------------------- + */ + +static void +CommonGetsCleanup(chanPtr, encoding) + Channel *chanPtr; + Tcl_Encoding encoding; +{ + ChannelBuffer *bufPtr, *nextPtr; + + bufPtr = chanPtr->inQueueHead; + for ( ; bufPtr != NULL; bufPtr = nextPtr) { + nextPtr = bufPtr->nextPtr; + if (bufPtr->nextRemoved < bufPtr->nextAdded) { + break; + } + RecycleBuffer(chanPtr, bufPtr, 0); + } + chanPtr->inQueueHead = bufPtr; + if (bufPtr == NULL) { + chanPtr->inQueueTail = NULL; + } else { + /* + * If any multi-byte characters were split across channel buffer + * boundaries, the split-up bytes were moved to the next channel + * buffer by FilterInputBytes(). Move the bytes back to their + * original buffer because the caller could change the channel's + * encoding which could change the interpretation of whether those + * bytes really made up multi-byte characters after all. + */ + + nextPtr = bufPtr->nextPtr; + for ( ; nextPtr != NULL; nextPtr = bufPtr->nextPtr) { + int extra; + + extra = bufPtr->bufLength - bufPtr->nextAdded; + if (extra > 0) { + memcpy((VOID *) (bufPtr->buf + bufPtr->nextAdded), + (VOID *) (nextPtr->buf + BUFFER_PADDING - extra), + (size_t) extra); + bufPtr->nextAdded += extra; + nextPtr->nextRemoved = BUFFER_PADDING; + } + bufPtr = nextPtr; + } + } + if (chanPtr->encoding == NULL) { + Tcl_FreeEncoding(encoding); + } +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_Read -- + * + * Reads a given number of bytes from a channel. EOL and EOF + * translation is done on the bytes being read, so the the number + * of bytes consumed from the channel may not be equal to the + * number of bytes stored in the destination buffer. + * + * No encoding conversions are applied to the bytes being read. + * + * Results: + * The number of bytes read, or -1 on error. Use Tcl_GetErrno() + * to retrieve the error code for the error that occurred. + * + * Side effects: + * May cause input to be buffered. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_Read(chan, dst, bytesToRead) + Tcl_Channel chan; /* The channel from which to read. */ + char *dst; /* Where to store input read. */ + int bytesToRead; /* Maximum number of bytes to read. */ +{ + Channel *chanPtr; + + chanPtr = (Channel *) chan; + if (CheckChannelErrors(chanPtr, TCL_READABLE) != 0) { + return -1; + } + + return DoRead(chanPtr, dst, bytesToRead); +} + +/* + *--------------------------------------------------------------------------- + * + * Tcl_ReadChars -- + * + * Reads from the channel until the requested number of characters + * have been seen, EOF is seen, or the channel would block. EOL + * and EOF translation is done. If reading binary data, the raw + * bytes are wrapped in a Tcl byte array object. Otherwise, the raw + * bytes are converted to UTF-8 using the channel's current encoding + * and stored in a Tcl string object. + * + * Results: + * The number of characters read, or -1 on error. Use Tcl_GetErrno() + * to retrieve the error code for the error that occurred. + * + * Side effects: + * May cause input to be buffered. + * + *--------------------------------------------------------------------------- + */ + +int +Tcl_ReadChars(chan, objPtr, toRead, appendFlag) + Tcl_Channel chan; /* The channel to read. */ + Tcl_Obj *objPtr; /* Input data is stored in this object. */ + int toRead; /* Maximum number of characters to store, + * or -1 to read all available data (up to EOF + * or when channel blocks). */ + int appendFlag; /* If non-zero, data read from the channel + * will be appended to the object. Otherwise, + * the data will replace the existing contents + * of the object. */ + +{ + Channel *chanPtr; + int offset, factor, copied, copiedNow, result; + ChannelBuffer *bufPtr; + Tcl_Encoding encoding; +#define UTF_EXPANSION_FACTOR 1024 + + chanPtr = (Channel *) chan; + if (CheckChannelErrors(chanPtr, TCL_READABLE) != 0) { + copied = -1; + goto done; + } + + encoding = chanPtr->encoding; + factor = UTF_EXPANSION_FACTOR; + + if (appendFlag == 0) { + if (encoding == NULL) { + Tcl_SetByteArrayLength(objPtr, 0); + } else { + Tcl_SetObjLength(objPtr, 0); + } + offset = 0; + } else { + if (encoding == NULL) { + Tcl_GetByteArrayFromObj(objPtr, &offset); + } else { + Tcl_GetStringFromObj(objPtr, &offset); + } + } + + for (copied = 0; (unsigned) toRead > 0; ) { + copiedNow = -1; + if (chanPtr->inQueueHead != NULL) { + if (encoding == NULL) { + copiedNow = ReadBytes(chanPtr, objPtr, toRead, &offset); + } else { + copiedNow = ReadChars(chanPtr, objPtr, toRead, &offset, + &factor); + } + + /* + * If the current buffer is empty recycle it. + */ + + bufPtr = chanPtr->inQueueHead; + if (bufPtr->nextRemoved == bufPtr->nextAdded) { + ChannelBuffer *nextPtr; + + nextPtr = bufPtr->nextPtr; + RecycleBuffer(chanPtr, bufPtr, 0); + chanPtr->inQueueHead = nextPtr; + if (nextPtr == NULL) { + chanPtr->inQueueTail = nextPtr; + } + } + } + if (copiedNow < 0) { + if (chanPtr->flags & CHANNEL_EOF) { + break; + } + if (chanPtr->flags & CHANNEL_BLOCKED) { + if (chanPtr->flags & CHANNEL_NONBLOCKING) { + break; + } + chanPtr->flags &= ~CHANNEL_BLOCKED; + } + result = GetInput(chanPtr); + if (result != 0) { + if (result == EAGAIN) { + break; + } + copied = -1; + goto done; + } + } else { + copied += copiedNow; + toRead -= copiedNow; + } + } + chanPtr->flags &= ~CHANNEL_BLOCKED; + if (encoding == NULL) { + Tcl_SetByteArrayLength(objPtr, offset); + } else { + Tcl_SetObjLength(objPtr, offset); + } + + done: + /* + * Update the notifier state so we don't block while there is still + * data in the buffers. + */ + + UpdateInterest(chanPtr); + return copied; +} +/* + *--------------------------------------------------------------------------- + * + * ReadBytes -- + * + * Reads from the channel until the requested number of bytes have + * been seen, EOF is seen, or the channel would block. Bytes from + * the channel are stored in objPtr as a ByteArray object. EOL + * and EOF translation are done. + * + * 'bytesToRead' can safely be a very large number because + * space is only allocated to hold data read from the channel + * as needed. + * + * Results: + * The return value is the number of bytes appended to the object + * and *offsetPtr is filled with the total number of bytes in the + * object (greater than the return value if there were already bytes + * in the object). + * + * Side effects: + * None. + * + *--------------------------------------------------------------------------- + */ + +static int +ReadBytes(chanPtr, objPtr, bytesToRead, offsetPtr) + Channel *chanPtr; /* The channel to read. */ + int bytesToRead; /* Maximum number of characters to store, + * or < 0 to get all available characters. + * Characters are obtained from the first + * buffer in the queue -- even if this number + * is larger than the number of characters + * available in the first buffer, only the + * characters from the first buffer are + * returned. */ + Tcl_Obj *objPtr; /* Input data is appended to this ByteArray + * object. Its length is how much space + * has been allocated to hold data, not how + * many bytes of data have been stored in the + * object. */ + int *offsetPtr; /* On input, contains how many bytes of + * objPtr have been used to hold data. On + * output, filled with how many bytes are now + * being used. */ +{ + int toRead, srcLen, srcRead, dstWrote, offset, length; + ChannelBuffer *bufPtr; + char *src, *dst; + + offset = *offsetPtr; + + bufPtr = chanPtr->inQueueHead; + src = bufPtr->buf + bufPtr->nextRemoved; + srcLen = bufPtr->nextAdded - bufPtr->nextRemoved; + + toRead = bytesToRead; + if ((unsigned) toRead > (unsigned) srcLen) { + toRead = srcLen; + } + + dst = (char *) Tcl_GetByteArrayFromObj(objPtr, &length); + if (toRead > length - offset - 1) { + /* + * Double the existing size of the object or make enough room to + * hold all the characters we may get from the source buffer, + * whichever is larger. + */ + + length = offset * 2; + if (offset < toRead) { + length = offset + toRead + 1; + } + dst = (char *) Tcl_SetByteArrayLength(objPtr, length); + } + dst += offset; + + if (chanPtr->flags & INPUT_NEED_NL) { + chanPtr->flags &= ~INPUT_NEED_NL; + if ((srcLen == 0) || (*src != '\n')) { + *dst = '\r'; + *offsetPtr += 1; + return 1; + } + *dst++ = '\n'; + src++; + srcLen--; + toRead--; + } + + srcRead = srcLen; + dstWrote = toRead; + if (TranslateInputEOL(chanPtr, dst, src, &dstWrote, &srcRead) != 0) { + if (dstWrote == 0) { + return -1; + } + } + bufPtr->nextRemoved += srcRead; + *offsetPtr += dstWrote; + return dstWrote; +} + +/* + *--------------------------------------------------------------------------- + * + * ReadChars -- + * + * Reads from the channel until the requested number of UTF-8 + * characters have been seen, EOF is seen, or the channel would + * block. Raw bytes from the channel are converted to UTF-8 + * and stored in objPtr. EOL and EOF translation is done. + * + * 'charsToRead' can safely be a very large number because + * space is only allocated to hold data read from the channel + * as needed. + * + * Results: + * The return value is the number of characters appended to + * the object, *offsetPtr is filled with the number of bytes that + * were appended, and *factorPtr is filled with the expansion + * factor used to guess how many bytes of UTF-8 to allocate to + * hold N source bytes. + * + * Side effects: + * None. + * + *--------------------------------------------------------------------------- + */ + +static int +ReadChars(chanPtr, objPtr, charsToRead, offsetPtr, factorPtr) + Channel *chanPtr; /* The channel to read. */ + int charsToRead; /* Maximum number of characters to store, + * or -1 to get all available characters. + * Characters are obtained from the first + * buffer in the queue -- even if this number + * is larger than the number of characters + * available in the first buffer, only the + * characters from the first buffer are + * returned. */ + Tcl_Obj *objPtr; /* Input data is appended to this object. + * objPtr->length is how much space has been + * allocated to hold data, not how many bytes + * of data have been stored in the object. */ + int *offsetPtr; /* On input, contains how many bytes of + * objPtr have been used to hold data. On + * output, filled with how many bytes are now + * being used. */ + int *factorPtr; /* On input, contains a guess of how many + * bytes need to be allocated to hold the + * result of converting N source bytes to + * UTF-8. On output, contains another guess + * based on the data seen so far. */ +{ + int toRead, factor, offset, spaceLeft, length; + int srcLen, srcRead, dstNeeded, dstRead, dstWrote, numChars; + ChannelBuffer *bufPtr; + char *src, *dst; + Tcl_EncodingState oldState; + + factor = *factorPtr; + offset = *offsetPtr; + + bufPtr = chanPtr->inQueueHead; + src = bufPtr->buf + bufPtr->nextRemoved; + srcLen = bufPtr->nextAdded - bufPtr->nextRemoved; + + toRead = charsToRead; + if ((unsigned) toRead > (unsigned) srcLen) { + toRead = srcLen; + } + + /* + * 'factor' is how much we guess that the bytes in the source buffer + * will expand when converted to UTF-8 chars. This guess comes from + * analyzing how many characters were produced by the previous + * pass. + */ + + dstNeeded = toRead * factor / UTF_EXPANSION_FACTOR; + spaceLeft = objPtr->length - offset - TCL_UTF_MAX - 1; + + if (dstNeeded > spaceLeft) { + /* + * Double the existing size of the object or make enough room to + * hold all the characters we want from the source buffer, + * whichever is larger. + */ + + length = offset * 2; + if (offset < dstNeeded) { + length = offset + dstNeeded; + } + spaceLeft = length - offset; + length += TCL_UTF_MAX + 1; + Tcl_SetObjLength(objPtr, length); + } + if (toRead == srcLen) { + /* + * Want to convert the whole buffer in one pass. If we have + * enough space, convert it using all available space in object + * rather than using the factor. + */ + + dstNeeded = spaceLeft; + } + dst = objPtr->bytes + offset; + + oldState = chanPtr->inputEncodingState; + if (chanPtr->flags & INPUT_NEED_NL) { + /* + * We want a '\n' because the last character we saw was '\r'. + */ + + chanPtr->flags &= ~INPUT_NEED_NL; + Tcl_ExternalToUtf(NULL, chanPtr->encoding, src, srcLen, + chanPtr->inputEncodingFlags, &chanPtr->inputEncodingState, + dst, TCL_UTF_MAX + 1, &srcRead, &dstWrote, &numChars); + if ((dstWrote > 0) && (*dst == '\n')) { + /* + * The next char was a '\n'. Consume it and produce a '\n'. + */ + + bufPtr->nextRemoved += srcRead; + } else { + /* + * The next char was not a '\n'. Produce a '\r'. + */ + + *dst = '\r'; + } + chanPtr->inputEncodingFlags &= ~TCL_ENCODING_START; + *offsetPtr += 1; + return 1; + } + + Tcl_ExternalToUtf(NULL, chanPtr->encoding, src, srcLen, + chanPtr->inputEncodingFlags, &chanPtr->inputEncodingState, dst, + dstNeeded + TCL_UTF_MAX, &srcRead, &dstWrote, &numChars); + if (srcRead == 0) { + /* + * Not enough bytes in src buffer to make a complete char. Copy + * the bytes to the next buffer to make a new contiguous string, + * then tell the caller to fill the buffer with more bytes. + */ + + ChannelBuffer *nextPtr; + + nextPtr = bufPtr->nextPtr; + if (nextPtr == NULL) { + /* + * There isn't enough data in the buffers to complete the next + * character, so we need to wait for more data before the next + * file event can be delivered. + */ + + chanPtr->flags |= CHANNEL_NEED_MORE_DATA; + return -1; + } + nextPtr->nextRemoved -= srcLen; + memcpy((VOID *) (nextPtr->buf + nextPtr->nextRemoved), (VOID *) src, + (size_t) srcLen); + RecycleBuffer(chanPtr, bufPtr, 0); + chanPtr->inQueueHead = nextPtr; + return ReadChars(chanPtr, objPtr, charsToRead, offsetPtr, factorPtr); + } + + dstRead = dstWrote; + if (TranslateInputEOL(chanPtr, dst, dst, &dstWrote, &dstRead) != 0) { + /* + * Hit EOF char. How many bytes of src correspond to where the + * EOF was located in dst? + */ + + if (dstWrote == 0) { + return -1; + } + chanPtr->inputEncodingState = oldState; + Tcl_ExternalToUtf(NULL, chanPtr->encoding, src, srcLen, + chanPtr->inputEncodingFlags, &chanPtr->inputEncodingState, + dst, dstRead + TCL_UTF_MAX, &srcRead, &dstWrote, &numChars); + TranslateInputEOL(chanPtr, dst, dst, &dstWrote, &dstRead); + } + + /* + * The number of characters that we got may be less than the number + * that we started with because "\r\n" sequences may have been + * turned into just '\n' in dst. + */ + + numChars -= (dstRead - dstWrote); + + if ((unsigned) numChars > (unsigned) toRead) { + /* + * Got too many chars. + */ + + char *eof; + + eof = Tcl_UtfAtIndex(dst, toRead); + chanPtr->inputEncodingState = oldState; + Tcl_ExternalToUtf(NULL, chanPtr->encoding, src, srcLen, + chanPtr->inputEncodingFlags, &chanPtr->inputEncodingState, + dst, eof - dst + TCL_UTF_MAX, &srcRead, &dstWrote, &numChars); + dstRead = dstWrote; + TranslateInputEOL(chanPtr, dst, dst, &dstWrote, &dstRead); + numChars -= (dstRead - dstWrote); + } + chanPtr->inputEncodingFlags &= ~TCL_ENCODING_START; + + bufPtr->nextRemoved += srcRead; + if (dstWrote > srcRead + 1) { + *factorPtr = dstWrote * UTF_EXPANSION_FACTOR / srcRead; + } + *offsetPtr += dstWrote; + return numChars; +} + +/* + *--------------------------------------------------------------------------- + * + * TranslateInputEOL -- + * + * Perform input EOL and EOF translation on the source buffer, + * leaving the translated result in the destination buffer. + * + * Results: + * The return value is 1 if the EOF character was found when copying + * bytes to the destination buffer, 0 otherwise. + * + * Side effects: + * None. + * + *--------------------------------------------------------------------------- + */ + +static int +TranslateInputEOL(chanPtr, dstStart, srcStart, dstLenPtr, srcLenPtr) + Channel *chanPtr; /* Channel being read, for EOL translation + * and EOF character. */ + char *dstStart; /* Output buffer filled with chars by + * applying appropriate EOL translation to + * source characters. */ + CONST char *srcStart; /* Source characters. */ + int *dstLenPtr; /* On entry, the maximum length of output + * buffer in bytes; must be <= *srcLenPtr. On + * exit, the number of bytes actually used in + * output buffer. */ + int *srcLenPtr; /* On entry, the length of source buffer. + * On exit, the number of bytes read from + * the source buffer. */ +{ + int dstLen, srcLen, inEofChar; + CONST char *eof; + + dstLen = *dstLenPtr; + + eof = NULL; + inEofChar = chanPtr->inEofChar; + if (inEofChar != '\0') { + /* + * Find EOF in translated buffer then compress out the EOL. The + * source buffer may be much longer than the destination buffer -- + * we only want to return EOF if the EOF has been copied to the + * destination buffer. + */ + + CONST char *src, *srcMax; + + srcMax = srcStart + *srcLenPtr; + for (src = srcStart; src < srcMax; src++) { + if (*src == inEofChar) { + eof = src; + srcLen = src - srcStart; + if (srcLen < dstLen) { + dstLen = srcLen; + } + *srcLenPtr = srcLen; + break; + } + } + } + switch (chanPtr->inputTranslation) { + case TCL_TRANSLATE_LF: { + if (dstStart != srcStart) { + memcpy((VOID *) dstStart, (VOID *) srcStart, (size_t) dstLen); + } + srcLen = dstLen; + break; + } + case TCL_TRANSLATE_CR: { + char *dst, *dstEnd; + + if (dstStart != srcStart) { + memcpy((VOID *) dstStart, (VOID *) srcStart, (size_t) dstLen); + } + dstEnd = dstStart + dstLen; + for (dst = dstStart; dst < dstEnd; dst++) { + if (*dst == '\r') { + *dst = '\n'; + } + } + srcLen = dstLen; + break; + } + case TCL_TRANSLATE_CRLF: { + char *dst; + CONST char *src, *srcEnd, *srcMax; + + dst = dstStart; + src = srcStart; + srcEnd = srcStart + dstLen; + srcMax = srcStart + *srcLenPtr; + + for ( ; src < srcEnd; ) { + if (*src == '\r') { + src++; + if (src >= srcMax) { + chanPtr->flags |= INPUT_NEED_NL; + } else if (*src == '\n') { + *dst++ = *src++; + } else { + *dst++ = '\r'; + } + } else { + *dst++ = *src++; + } + } + srcLen = src - srcStart; + dstLen = dst - dstStart; + break; + } + case TCL_TRANSLATE_AUTO: { + char *dst; + CONST char *src, *srcEnd, *srcMax; + + dst = dstStart; + src = srcStart; + srcEnd = srcStart + dstLen; + srcMax = srcStart + *srcLenPtr; + + if ((chanPtr->flags & INPUT_SAW_CR) && (src < srcMax)) { + if (*src == '\n') { + src++; + } + chanPtr->flags &= ~INPUT_SAW_CR; + } + for ( ; src < srcEnd; ) { + if (*src == '\r') { + src++; + if (src >= srcMax) { + chanPtr->flags |= INPUT_SAW_CR; + } else if (*src == '\n') { + if (srcEnd < srcMax) { + srcEnd++; + } + src++; + } + *dst++ = '\n'; + } else { + *dst++ = *src++; + } + } + srcLen = src - srcStart; + dstLen = dst - dstStart; + break; + } + default: { /* lint. */ + return 0; + } + } + *dstLenPtr = dstLen; + + if ((eof != NULL) && (srcStart + srcLen >= eof)) { + /* + * EOF character was seen in EOL translated range. Leave current + * file position pointing at the EOF character, but don't store the + * EOF character in the output string. + */ + + chanPtr->flags |= (CHANNEL_EOF | CHANNEL_STICKY_EOF); + chanPtr->inputEncodingFlags |= TCL_ENCODING_END; + chanPtr->flags &= ~(INPUT_SAW_CR | INPUT_NEED_NL); + return 1; + } + + *srcLenPtr = srcLen; + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_Ungets -- + * + * Causes the supplied string to be added to the input queue of + * the channel, at either the head or tail of the queue. + * + * Results: + * The number of bytes stored in the channel, or -1 on error. + * + * Side effects: + * Adds input to the input queue of a channel. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_Ungets(chan, str, len, atEnd) + Tcl_Channel chan; /* The channel for which to add the input. */ + char *str; /* The input itself. */ + int len; /* The length of the input. */ + int atEnd; /* If non-zero, add at end of queue; otherwise + * add at head of queue. */ +{ + Channel *chanPtr; /* The real IO channel. */ + ChannelBuffer *bufPtr; /* Buffer to contain the data. */ + int i, flags; + + chanPtr = (Channel *) chan; + + /* + * CheckChannelErrors clears too many flag bits in this one case. + */ + + flags = chanPtr->flags; + if (CheckChannelErrors(chanPtr, TCL_READABLE) != 0) { + len = -1; + goto done; + } + chanPtr->flags = flags; + + /* + * If we have encountered a sticky EOF, just punt without storing. + * (sticky EOF is set if we have seen the input eofChar, to prevent + * reading beyond the eofChar). Otherwise, clear the EOF flags, and + * clear the BLOCKED bit. We want to discover these conditions anew + * in each operation. + */ + + if (chanPtr->flags & CHANNEL_STICKY_EOF) { + goto done; + } + chanPtr->flags &= (~(CHANNEL_BLOCKED | CHANNEL_EOF)); + + bufPtr = AllocChannelBuffer(len); + for (i = 0; i < len; i++) { + bufPtr->buf[i] = str[i]; + } + bufPtr->nextAdded += len; + + if (chanPtr->inQueueHead == (ChannelBuffer *) NULL) { + bufPtr->nextPtr = (ChannelBuffer *) NULL; + chanPtr->inQueueHead = bufPtr; + chanPtr->inQueueTail = bufPtr; + } else if (atEnd) { + bufPtr->nextPtr = (ChannelBuffer *) NULL; + chanPtr->inQueueTail->nextPtr = bufPtr; + chanPtr->inQueueTail = bufPtr; + } else { + bufPtr->nextPtr = chanPtr->inQueueHead; + chanPtr->inQueueHead = bufPtr; + } + + done: + /* + * Update the notifier state so we don't block while there is still + * data in the buffers. + */ + + UpdateInterest(chanPtr); + return len; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_Flush -- + * + * Flushes output data on a channel. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * May flush output queued on this channel. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_Flush(chan) + Tcl_Channel chan; /* The Channel to flush. */ +{ + int result; /* Of calling FlushChannel. */ + Channel *chanPtr; /* The actual channel. */ + + chanPtr = (Channel *) chan; + if (CheckChannelErrors(chanPtr, TCL_WRITABLE) != 0) { + return -1; + } + + /* + * Force current output buffer to be output also. + */ + + if ((chanPtr->curOutPtr != NULL) + && (chanPtr->curOutPtr->nextAdded > 0)) { + chanPtr->flags |= BUFFER_READY; + } + + result = FlushChannel(NULL, chanPtr, 0); + if (result != 0) { + return TCL_ERROR; + } + + return TCL_OK; +} + +/* + *---------------------------------------------------------------------- + * + * DiscardInputQueued -- + * + * Discards any input read from the channel but not yet consumed + * by Tcl reading commands. + * + * Results: + * None. + * + * Side effects: + * May discard input from the channel. If discardLastBuffer is zero, + * leaves one buffer in place for back-filling. + * + *---------------------------------------------------------------------- + */ + +static void +DiscardInputQueued(chanPtr, discardSavedBuffers) + Channel *chanPtr; /* Channel on which to discard + * the queued input. */ + int discardSavedBuffers; /* If non-zero, discard all buffers including + * last one. */ +{ + ChannelBuffer *bufPtr, *nxtPtr; /* Loop variables. */ + + bufPtr = chanPtr->inQueueHead; + chanPtr->inQueueHead = (ChannelBuffer *) NULL; + chanPtr->inQueueTail = (ChannelBuffer *) NULL; + for (; bufPtr != (ChannelBuffer *) NULL; bufPtr = nxtPtr) { + nxtPtr = bufPtr->nextPtr; + RecycleBuffer(chanPtr, bufPtr, discardSavedBuffers); + } + + /* + * If discardSavedBuffers is nonzero, must also discard any previously + * saved buffer in the saveInBufPtr field. + */ + + if (discardSavedBuffers) { + if (chanPtr->saveInBufPtr != (ChannelBuffer *) NULL) { + ckfree((char *) chanPtr->saveInBufPtr); + chanPtr->saveInBufPtr = (ChannelBuffer *) NULL; + } + } +} + +/* + *--------------------------------------------------------------------------- + * + * GetInput -- + * + * Reads input data from a device into a channel buffer. + * + * Results: + * The return value is the Posix error code if an error occurred while + * reading from the file, or 0 otherwise. + * + * Side effects: + * Reads from the underlying device. + * + *--------------------------------------------------------------------------- + */ + +static int +GetInput(chanPtr) + Channel *chanPtr; /* Channel to read input from. */ +{ + int toRead; /* How much to read? */ + int result; /* Of calling driver. */ + int nread; /* How much was read from channel? */ + ChannelBuffer *bufPtr; /* New buffer to add to input queue. */ + + /* + * Prevent reading from a dead channel -- a channel that has been closed + * but not yet deallocated, which can happen if the exit handler for + * channel cleanup has run but the channel is still registered in some + * interpreter. + */ + + if (CheckForDeadChannel(NULL, chanPtr)) { + return EINVAL; + } + + /* + * See if we can fill an existing buffer. If we can, read only + * as much as will fit in it. Otherwise allocate a new buffer, + * add it to the input queue and attempt to fill it to the max. + */ + + bufPtr = chanPtr->inQueueTail; + if ((bufPtr != NULL) && (bufPtr->nextAdded < bufPtr->bufLength)) { + toRead = bufPtr->bufLength - bufPtr->nextAdded; + } else { + bufPtr = chanPtr->saveInBufPtr; + chanPtr->saveInBufPtr = NULL; + if (bufPtr == NULL) { + bufPtr = AllocChannelBuffer(chanPtr->bufSize); + } + bufPtr->nextPtr = (ChannelBuffer *) NULL; + + toRead = chanPtr->bufSize; + if (chanPtr->inQueueTail == NULL) { + chanPtr->inQueueHead = bufPtr; + } else { + chanPtr->inQueueTail->nextPtr = bufPtr; + } + chanPtr->inQueueTail = bufPtr; + } + + /* + * If EOF is set, we should avoid calling the driver because on some + * platforms it is impossible to read from a device after EOF. + */ + + if (chanPtr->flags & CHANNEL_EOF) { + return 0; + } + + nread = (*chanPtr->typePtr->inputProc)(chanPtr->instanceData, + bufPtr->buf + bufPtr->nextAdded, toRead, &result); + + if (nread > 0) { + bufPtr->nextAdded += nread; + + /* + * If we get a short read, signal up that we may be BLOCKED. We + * should avoid calling the driver because on some platforms we + * will block in the low level reading code even though the + * channel is set into nonblocking mode. + */ + + if (nread < toRead) { + chanPtr->flags |= CHANNEL_BLOCKED; + } + } else if (nread == 0) { + chanPtr->flags |= CHANNEL_EOF; + chanPtr->inputEncodingFlags |= TCL_ENCODING_END; + } else if (nread < 0) { + /* + * DO NOT check for EINTR here. If you try again during + * an EINTR (interrupt), nothing else can try to detect + * them (such as TclX). Check with Mark Diekhans for a + * better answer. + */ + + if ((result == EWOULDBLOCK) || (result == EAGAIN)) { + chanPtr->flags |= CHANNEL_BLOCKED; + result = EAGAIN; + } + Tcl_SetErrno(result); + return result; + } + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_Seek -- + * + * Implements seeking on Tcl Channels. This is a public function + * so that other C facilities may be implemented on top of it. + * + * Results: + * The new access point or -1 on error. If error, use Tcl_GetErrno() + * to retrieve the POSIX error code for the error that occurred. + * + * Side effects: + * May flush output on the channel. May discard queued input. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_Seek(chan, offset, mode) + Tcl_Channel chan; /* The channel on which to seek. */ + int offset; /* Offset to seek to. */ + int mode; /* Relative to which location to seek? */ +{ + Channel *chanPtr; /* The real IO channel. */ + ChannelBuffer *bufPtr; + int inputBuffered, outputBuffered; + int result; /* Of device driver operations. */ + int curPos; /* Position on the device. */ + int wasAsync; /* Was the channel nonblocking before the + * seek operation? If so, must restore to + * nonblocking mode after the seek. */ + + chanPtr = (Channel *) chan; + if (CheckChannelErrors(chanPtr, TCL_WRITABLE | TCL_READABLE) != 0) { + return -1; + } + + /* + * Disallow seek on dead channels -- channels that have been closed but + * not yet been deallocated. Such channels can be found if the exit + * handler for channel cleanup has run but the channel is still + * registered in an interpreter. + */ + + if (CheckForDeadChannel(NULL,chanPtr)) return -1; + + /* + * Disallow seek on channels whose type does not have a seek procedure + * defined. This means that the channel does not support seeking. + */ + + if (chanPtr->typePtr->seekProc == (Tcl_DriverSeekProc *) NULL) { + Tcl_SetErrno(EINVAL); + return -1; + } + + /* + * Compute how much input and output is buffered. If both input and + * output is buffered, cannot compute the current position. + */ + + for (bufPtr = chanPtr->inQueueHead, inputBuffered = 0; + bufPtr != (ChannelBuffer *) NULL; + bufPtr = bufPtr->nextPtr) { + inputBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); + } + for (bufPtr = chanPtr->outQueueHead, outputBuffered = 0; + bufPtr != (ChannelBuffer *) NULL; + bufPtr = bufPtr->nextPtr) { + outputBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); + } + if ((chanPtr->curOutPtr != (ChannelBuffer *) NULL) && + (chanPtr->curOutPtr->nextAdded > chanPtr->curOutPtr->nextRemoved)) { + chanPtr->flags |= BUFFER_READY; + outputBuffered += + (chanPtr->curOutPtr->nextAdded - chanPtr->curOutPtr->nextRemoved); + } + + if ((inputBuffered != 0) && (outputBuffered != 0)) { + Tcl_SetErrno(EFAULT); + return -1; + } + + /* + * If we are seeking relative to the current position, compute the + * corrected offset taking into account the amount of unread input. + */ + + if (mode == SEEK_CUR) { + offset -= inputBuffered; + } + + /* + * Discard any queued input - this input should not be read after + * the seek. + */ + + DiscardInputQueued(chanPtr, 0); + + /* + * Reset EOF and BLOCKED flags. We invalidate them by moving the + * access point. Also clear CR related flags. + */ + + chanPtr->flags &= + (~(CHANNEL_EOF | CHANNEL_STICKY_EOF | CHANNEL_BLOCKED | INPUT_SAW_CR)); + + /* + * If the channel is in asynchronous output mode, switch it back + * to synchronous mode and cancel any async flush that may be + * scheduled. After the flush, the channel will be put back into + * asynchronous output mode. + */ + + wasAsync = 0; + if (chanPtr->flags & CHANNEL_NONBLOCKING) { + wasAsync = 1; + result = 0; + if (chanPtr->typePtr->blockModeProc != NULL) { + result = (chanPtr->typePtr->blockModeProc) (chanPtr->instanceData, + TCL_MODE_BLOCKING); + } + if (result != 0) { + Tcl_SetErrno(result); + return -1; + } + chanPtr->flags &= (~(CHANNEL_NONBLOCKING)); + if (chanPtr->flags & BG_FLUSH_SCHEDULED) { + chanPtr->flags &= (~(BG_FLUSH_SCHEDULED)); + } + } + + /* + * If the flush fails we cannot recover the original position. In + * that case the seek is not attempted because we do not know where + * the access position is - instead we return the error. FlushChannel + * has already called Tcl_SetErrno() to report the error upwards. + * If the flush succeeds we do the seek also. + */ + + if (FlushChannel(NULL, chanPtr, 0) != 0) { + curPos = -1; + } else { + + /* + * Now seek to the new position in the channel as requested by the + * caller. + */ + + curPos = (chanPtr->typePtr->seekProc) (chanPtr->instanceData, + (long) offset, mode, &result); + if (curPos == -1) { + Tcl_SetErrno(result); + } + } + + /* + * Restore to nonblocking mode if that was the previous behavior. + * + * NOTE: Even if there was an async flush active we do not restore + * it now because we already flushed all the queued output, above. + */ + + if (wasAsync) { + chanPtr->flags |= CHANNEL_NONBLOCKING; + result = 0; + if (chanPtr->typePtr->blockModeProc != NULL) { + result = (chanPtr->typePtr->blockModeProc) (chanPtr->instanceData, + TCL_MODE_NONBLOCKING); + } + if (result != 0) { + Tcl_SetErrno(result); + return -1; + } + } + + return curPos; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_Tell -- + * + * Returns the position of the next character to be read/written on + * this channel. + * + * Results: + * A nonnegative integer on success, -1 on failure. If failed, + * use Tcl_GetErrno() to retrieve the POSIX error code for the + * error that occurred. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_Tell(chan) + Tcl_Channel chan; /* The channel to return pos for. */ +{ + Channel *chanPtr; /* The actual channel to tell on. */ + ChannelBuffer *bufPtr; + int inputBuffered, outputBuffered; + int result; /* Of calling device driver. */ + int curPos; /* Position on device. */ + + chanPtr = (Channel *) chan; + if (CheckChannelErrors(chanPtr, TCL_WRITABLE | TCL_READABLE) != 0) { + return -1; + } + + /* + * Disallow tell on dead channels -- channels that have been closed but + * not yet been deallocated. Such channels can be found if the exit + * handler for channel cleanup has run but the channel is still + * registered in an interpreter. + */ + + if (CheckForDeadChannel(NULL,chanPtr)) { + return -1; + } + + /* + * Disallow tell on channels whose type does not have a seek procedure + * defined. This means that the channel does not support seeking. + */ + + if (chanPtr->typePtr->seekProc == (Tcl_DriverSeekProc *) NULL) { + Tcl_SetErrno(EINVAL); + return -1; + } + + /* + * Compute how much input and output is buffered. If both input and + * output is buffered, cannot compute the current position. + */ + + for (bufPtr = chanPtr->inQueueHead, inputBuffered = 0; + bufPtr != (ChannelBuffer *) NULL; + bufPtr = bufPtr->nextPtr) { + inputBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); + } + for (bufPtr = chanPtr->outQueueHead, outputBuffered = 0; + bufPtr != (ChannelBuffer *) NULL; + bufPtr = bufPtr->nextPtr) { + outputBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); + } + if ((chanPtr->curOutPtr != (ChannelBuffer *) NULL) && + (chanPtr->curOutPtr->nextAdded > chanPtr->curOutPtr->nextRemoved)) { + chanPtr->flags |= BUFFER_READY; + outputBuffered += + (chanPtr->curOutPtr->nextAdded - chanPtr->curOutPtr->nextRemoved); + } + + if ((inputBuffered != 0) && (outputBuffered != 0)) { + Tcl_SetErrno(EFAULT); + return -1; + } + + /* + * Get the current position in the device and compute the position + * where the next character will be read or written. + */ + + curPos = (chanPtr->typePtr->seekProc) (chanPtr->instanceData, + (long) 0, SEEK_CUR, &result); + if (curPos == -1) { + Tcl_SetErrno(result); + return -1; + } + if (inputBuffered != 0) { + return (curPos - inputBuffered); + } + return (curPos + outputBuffered); +} + +/* + *--------------------------------------------------------------------------- + * + * CheckChannelErrors -- + * + * See if the channel is in an ready state and can perform the + * desired operation. + * + * Results: + * The return value is 0 if the channel is OK, otherwise the + * return value is -1 and errno is set to indicate the error. + * + * Side effects: + * May clear the EOF and/or BLOCKED bits if reading from channel. + * + *--------------------------------------------------------------------------- + */ + +static int +CheckChannelErrors(chanPtr, direction) + Channel *chanPtr; /* Channel to check. */ + int direction; /* Test if channel supports desired operation: + * TCL_READABLE, TCL_WRITABLE. */ +{ + /* + * Check for unreported error. + */ + + if (chanPtr->unreportedError != 0) { + Tcl_SetErrno(chanPtr->unreportedError); + chanPtr->unreportedError = 0; + return -1; + } + + /* + * Fail if the channel is not opened for desired operation. + */ + + if ((chanPtr->flags & direction) == 0) { + Tcl_SetErrno(EACCES); + return -1; + } + + /* + * Fail if the channel is in the middle of a background copy. + */ + + if (chanPtr->csPtr != NULL) { + Tcl_SetErrno(EBUSY); + return -1; + } + + if (direction == TCL_READABLE) { + /* + * If we have not encountered a sticky EOF, clear the EOF bit + * (sticky EOF is set if we have seen the input eofChar, to prevent + * reading beyond the eofChar). Also, always clear the BLOCKED bit. + * We want to discover these conditions anew in each operation. + */ + + if ((chanPtr->flags & CHANNEL_STICKY_EOF) == 0) { + chanPtr->flags &= ~CHANNEL_EOF; + } + chanPtr->flags &= ~(CHANNEL_BLOCKED | CHANNEL_NEED_MORE_DATA); + } + + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_Eof -- + * + * Returns 1 if the channel is at EOF, 0 otherwise. + * + * Results: + * 1 or 0, always. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_Eof(chan) + Tcl_Channel chan; /* Does this channel have EOF? */ +{ + Channel *chanPtr; /* The real channel structure. */ + + chanPtr = (Channel *) chan; + return ((chanPtr->flags & CHANNEL_STICKY_EOF) || + ((chanPtr->flags & CHANNEL_EOF) && (Tcl_InputBuffered(chan) == 0))) + ? 1 : 0; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_InputBlocked -- + * + * Returns 1 if input is blocked on this channel, 0 otherwise. + * + * Results: + * 0 or 1, always. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_InputBlocked(chan) + Tcl_Channel chan; /* Is this channel blocked? */ +{ + Channel *chanPtr; /* The real channel structure. */ + + chanPtr = (Channel *) chan; + return (chanPtr->flags & CHANNEL_BLOCKED) ? 1 : 0; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_InputBuffered -- + * + * Returns the number of bytes of input currently buffered in the + * internal buffer of a channel. + * + * Results: + * The number of input bytes buffered, or zero if the channel is not + * open for reading. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_InputBuffered(chan) + Tcl_Channel chan; /* The channel to query. */ +{ + Channel *chanPtr; + int bytesBuffered; + ChannelBuffer *bufPtr; + + chanPtr = (Channel *) chan; + for (bytesBuffered = 0, bufPtr = chanPtr->inQueueHead; + bufPtr != (ChannelBuffer *) NULL; + bufPtr = bufPtr->nextPtr) { + bytesBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); + } + return bytesBuffered; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_SetChannelBufferSize -- + * + * Sets the size of buffers to allocate to store input or output + * in the channel. The size must be between 10 bytes and 1 MByte. + * + * Results: + * None. + * + * Side effects: + * Sets the size of buffers subsequently allocated for this channel. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_SetChannelBufferSize(chan, sz) + Tcl_Channel chan; /* The channel whose buffer size + * to set. */ + int sz; /* The size to set. */ +{ + Channel *chanPtr; + + /* + * If the buffer size is smaller than 10 bytes or larger than one MByte, + * do not accept the requested size and leave the current buffer size. + */ + + if (sz < 10) { + return; + } + if (sz > (1024 * 1024)) { + return; + } + + chanPtr = (Channel *) chan; + chanPtr->bufSize = sz; + + if (chanPtr->outputStage != NULL) { + ckfree((char *) chanPtr->outputStage); + chanPtr->outputStage = NULL; + } + if ((chanPtr->encoding != NULL) && (chanPtr->flags & TCL_WRITABLE)) { + chanPtr->outputStage = (char *) + ckalloc((unsigned) (chanPtr->bufSize + 2)); + } +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetChannelBufferSize -- + * + * Retrieves the size of buffers to allocate for this channel. + * + * Results: + * The size. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_GetChannelBufferSize(chan) + Tcl_Channel chan; /* The channel for which to find the + * buffer size. */ +{ + Channel *chanPtr; + + chanPtr = (Channel *) chan; + return chanPtr->bufSize; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_BadChannelOption -- + * + * This procedure generates a "bad option" error message in an + * (optional) interpreter. It is used by channel drivers when + * a invalid Set/Get option is requested. Its purpose is to concatenate + * the generic options list to the specific ones and factorize + * the generic options error message string. + * + * Results: + * TCL_ERROR. + * + * Side effects: + * An error message is generated in interp's result object to + * indicate that a command was invoked with the a bad option + * The message has the form + * bad option "blah": should be one of + * <...generic options...>+<...specific options...> + * "blah" is the optionName argument and "<specific options>" + * is a space separated list of specific option words. + * The function takes good care of inserting minus signs before + * each option, commas after, and an "or" before the last option. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_BadChannelOption(interp, optionName, optionList) + Tcl_Interp *interp; /* Current interpreter. (can be NULL)*/ + char *optionName; /* 'bad option' name */ + char *optionList; /* Specific options list to append + * to the standard generic options. + * can be NULL for generic options + * only. + */ +{ + if (interp) { + CONST char *genericopt = + "blocking buffering buffersize eofchar translation"; + char **argv; + int argc, i; + Tcl_DString ds; + + Tcl_DStringInit(&ds); + Tcl_DStringAppend(&ds, (char *) genericopt, -1); + if (optionList && (*optionList)) { + Tcl_DStringAppend(&ds, " ", 1); + Tcl_DStringAppend(&ds, optionList, -1); + } + if (Tcl_SplitList(interp, Tcl_DStringValue(&ds), + &argc, &argv) != TCL_OK) { + panic("malformed option list in channel driver"); + } + Tcl_ResetResult(interp); + Tcl_AppendResult(interp, "bad option \"", optionName, + "\": should be one of ", (char *) NULL); + argc--; + for (i = 0; i < argc; i++) { + Tcl_AppendResult(interp, "-", argv[i], ", ", (char *) NULL); + } + Tcl_AppendResult(interp, "or -", argv[i], (char *) NULL); + Tcl_DStringFree(&ds); + ckfree((char *) argv); + } + Tcl_SetErrno(EINVAL); + return TCL_ERROR; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetChannelOption -- + * + * Gets a mode associated with an IO channel. If the optionName arg + * is non NULL, retrieves the value of that option. If the optionName + * arg is NULL, retrieves a list of alternating option names and + * values for the given channel. + * + * Results: + * A standard Tcl result. Also sets the supplied DString to the + * string value of the option(s) returned. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_GetChannelOption(interp, chan, optionName, dsPtr) + Tcl_Interp *interp; /* For error reporting - can be NULL. */ + Tcl_Channel chan; /* Channel on which to get option. */ + char *optionName; /* Option to get. */ + Tcl_DString *dsPtr; /* Where to store value(s). */ +{ + size_t len; /* Length of optionName string. */ + char optionVal[128]; /* Buffer for sprintf. */ + Channel *chanPtr = (Channel *) chan; + int flags; + + /* + * If we are in the middle of a background copy, use the saved flags. + */ + + if (chanPtr->csPtr) { + if (chanPtr == chanPtr->csPtr->readPtr) { + flags = chanPtr->csPtr->readFlags; + } else { + flags = chanPtr->csPtr->writeFlags; + } + } else { + flags = chanPtr->flags; + } + + /* + * Disallow options on dead channels -- channels that have been closed but + * not yet been deallocated. Such channels can be found if the exit + * handler for channel cleanup has run but the channel is still + * registered in an interpreter. + */ + + if (CheckForDeadChannel(interp,chanPtr)) return TCL_ERROR; + + /* + * If the optionName is NULL it means that we want a list of all + * options and values. + */ + + if (optionName == (char *) NULL) { + len = 0; + } else { + len = strlen(optionName); + } + + if ((len == 0) || ((len > 2) && (optionName[1] == 'b') && + (strncmp(optionName, "-blocking", len) == 0))) { + if (len == 0) { + Tcl_DStringAppendElement(dsPtr, "-blocking"); + } + Tcl_DStringAppendElement(dsPtr, + (flags & CHANNEL_NONBLOCKING) ? "0" : "1"); + if (len > 0) { + return TCL_OK; + } + } + if ((len == 0) || ((len > 7) && (optionName[1] == 'b') && + (strncmp(optionName, "-buffering", len) == 0))) { + if (len == 0) { + Tcl_DStringAppendElement(dsPtr, "-buffering"); + } + if (flags & CHANNEL_LINEBUFFERED) { + Tcl_DStringAppendElement(dsPtr, "line"); + } else if (flags & CHANNEL_UNBUFFERED) { + Tcl_DStringAppendElement(dsPtr, "none"); + } else { + Tcl_DStringAppendElement(dsPtr, "full"); + } + if (len > 0) { + return TCL_OK; + } + } + if ((len == 0) || ((len > 7) && (optionName[1] == 'b') && + (strncmp(optionName, "-buffersize", len) == 0))) { + if (len == 0) { + Tcl_DStringAppendElement(dsPtr, "-buffersize"); + } + TclFormatInt(optionVal, chanPtr->bufSize); + Tcl_DStringAppendElement(dsPtr, optionVal); + if (len > 0) { + return TCL_OK; + } + } + if ((len == 0) || + ((len > 2) && (optionName[1] == 'e') && + (strncmp(optionName, "-encoding", len) == 0))) { + if (len == 0) { + Tcl_DStringAppendElement(dsPtr, "-encoding"); + } + if (chanPtr->encoding == NULL) { + Tcl_DStringAppendElement(dsPtr, "binary"); + } else { + Tcl_DStringAppendElement(dsPtr, + Tcl_GetEncodingName(chanPtr->encoding)); + } + if (len > 0) { + return TCL_OK; + } + } + if ((len == 0) || + ((len > 2) && (optionName[1] == 'e') && + (strncmp(optionName, "-eofchar", len) == 0))) { + if (len == 0) { + Tcl_DStringAppendElement(dsPtr, "-eofchar"); + } + if (((flags & (TCL_READABLE|TCL_WRITABLE)) == + (TCL_READABLE|TCL_WRITABLE)) && (len == 0)) { + Tcl_DStringStartSublist(dsPtr); + } + if (flags & TCL_READABLE) { + if (chanPtr->inEofChar == 0) { + Tcl_DStringAppendElement(dsPtr, ""); + } else { + char buf[4]; + + sprintf(buf, "%c", chanPtr->inEofChar); + Tcl_DStringAppendElement(dsPtr, buf); + } + } + if (flags & TCL_WRITABLE) { + if (chanPtr->outEofChar == 0) { + Tcl_DStringAppendElement(dsPtr, ""); + } else { + char buf[4]; + + sprintf(buf, "%c", chanPtr->outEofChar); + Tcl_DStringAppendElement(dsPtr, buf); + } + } + if (((flags & (TCL_READABLE|TCL_WRITABLE)) == + (TCL_READABLE|TCL_WRITABLE)) && (len == 0)) { + Tcl_DStringEndSublist(dsPtr); + } + if (len > 0) { + return TCL_OK; + } + } + if ((len == 0) || + ((len > 1) && (optionName[1] == 't') && + (strncmp(optionName, "-translation", len) == 0))) { + if (len == 0) { + Tcl_DStringAppendElement(dsPtr, "-translation"); + } + if (((flags & (TCL_READABLE|TCL_WRITABLE)) == + (TCL_READABLE|TCL_WRITABLE)) && (len == 0)) { + Tcl_DStringStartSublist(dsPtr); + } + if (flags & TCL_READABLE) { + if (chanPtr->inputTranslation == TCL_TRANSLATE_AUTO) { + Tcl_DStringAppendElement(dsPtr, "auto"); + } else if (chanPtr->inputTranslation == TCL_TRANSLATE_CR) { + Tcl_DStringAppendElement(dsPtr, "cr"); + } else if (chanPtr->inputTranslation == TCL_TRANSLATE_CRLF) { + Tcl_DStringAppendElement(dsPtr, "crlf"); + } else { + Tcl_DStringAppendElement(dsPtr, "lf"); + } + } + if (flags & TCL_WRITABLE) { + if (chanPtr->outputTranslation == TCL_TRANSLATE_AUTO) { + Tcl_DStringAppendElement(dsPtr, "auto"); + } else if (chanPtr->outputTranslation == TCL_TRANSLATE_CR) { + Tcl_DStringAppendElement(dsPtr, "cr"); + } else if (chanPtr->outputTranslation == TCL_TRANSLATE_CRLF) { + Tcl_DStringAppendElement(dsPtr, "crlf"); + } else { + Tcl_DStringAppendElement(dsPtr, "lf"); + } + } + if (((flags & (TCL_READABLE|TCL_WRITABLE)) == + (TCL_READABLE|TCL_WRITABLE)) && (len == 0)) { + Tcl_DStringEndSublist(dsPtr); + } + if (len > 0) { + return TCL_OK; + } + } + if (chanPtr->typePtr->getOptionProc != (Tcl_DriverGetOptionProc *) NULL) { + /* + * let the driver specific handle additional options + * and result code and message. + */ + + return (chanPtr->typePtr->getOptionProc) (chanPtr->instanceData, + interp, optionName, dsPtr); + } else { + /* + * no driver specific options case. + */ + + if (len == 0) { + return TCL_OK; + } + return Tcl_BadChannelOption(interp, optionName, NULL); + } +} + +/* + *--------------------------------------------------------------------------- + * + * Tcl_SetChannelOption -- + * + * Sets an option on a channel. + * + * Results: + * A standard Tcl result. On error, sets interp's result object + * if interp is not NULL. + * + * Side effects: + * May modify an option on a device. + * + *--------------------------------------------------------------------------- + */ + +int +Tcl_SetChannelOption(interp, chan, optionName, newValue) + Tcl_Interp *interp; /* For error reporting - can be NULL. */ + Tcl_Channel chan; /* Channel on which to set mode. */ + char *optionName; /* Which option to set? */ + char *newValue; /* New value for option. */ +{ + int newMode; /* New (numeric) mode to sert. */ + Channel *chanPtr; /* The real IO channel. */ + size_t len; /* Length of optionName string. */ + int argc; + char **argv; + + chanPtr = (Channel *) chan; + + /* + * If the channel is in the middle of a background copy, fail. + */ + + if (chanPtr->csPtr) { + if (interp) { + Tcl_AppendResult(interp, + "unable to set channel options: background copy in progress", + (char *) NULL); + } + return TCL_ERROR; + } + + + /* + * Disallow options on dead channels -- channels that have been closed but + * not yet been deallocated. Such channels can be found if the exit + * handler for channel cleanup has run but the channel is still + * registered in an interpreter. + */ + + if (CheckForDeadChannel(NULL,chanPtr)) return TCL_ERROR; + + len = strlen(optionName); + + if ((len > 2) && (optionName[1] == 'b') && + (strncmp(optionName, "-blocking", len) == 0)) { + if (Tcl_GetBoolean(interp, newValue, &newMode) == TCL_ERROR) { + return TCL_ERROR; + } + if (newMode) { + newMode = TCL_MODE_BLOCKING; + } else { + newMode = TCL_MODE_NONBLOCKING; + } + return SetBlockMode(interp, chanPtr, newMode); + } else if ((len > 7) && (optionName[1] == 'b') && + (strncmp(optionName, "-buffering", len) == 0)) { + len = strlen(newValue); + if ((newValue[0] == 'f') && (strncmp(newValue, "full", len) == 0)) { + chanPtr->flags &= + (~(CHANNEL_UNBUFFERED|CHANNEL_LINEBUFFERED)); + } else if ((newValue[0] == 'l') && + (strncmp(newValue, "line", len) == 0)) { + chanPtr->flags &= (~(CHANNEL_UNBUFFERED)); + chanPtr->flags |= CHANNEL_LINEBUFFERED; + } else if ((newValue[0] == 'n') && + (strncmp(newValue, "none", len) == 0)) { + chanPtr->flags &= (~(CHANNEL_LINEBUFFERED)); + chanPtr->flags |= CHANNEL_UNBUFFERED; + } else { + if (interp) { + Tcl_AppendResult(interp, "bad value for -buffering: ", + "must be one of full, line, or none", + (char *) NULL); + return TCL_ERROR; + } + } + return TCL_OK; + } else if ((len > 7) && (optionName[1] == 'b') && + (strncmp(optionName, "-buffersize", len) == 0)) { + chanPtr->bufSize = atoi(newValue); /* INTL: "C", UTF safe. */ + if ((chanPtr->bufSize < 10) || (chanPtr->bufSize > (1024 * 1024))) { + chanPtr->bufSize = CHANNELBUFFER_DEFAULT_SIZE; + } + } else if ((len > 2) && (optionName[1] == 'e') && + (strncmp(optionName, "-encoding", len) == 0)) { + Tcl_Encoding encoding; + + if ((newValue[0] == '\0') || (strcmp(newValue, "binary") == 0)) { + encoding = NULL; + } else { + encoding = Tcl_GetEncoding(interp, newValue); + if (encoding == NULL) { + return TCL_ERROR; + } + } + Tcl_FreeEncoding(chanPtr->encoding); + chanPtr->encoding = encoding; + chanPtr->inputEncodingState = NULL; + chanPtr->inputEncodingFlags = TCL_ENCODING_START; + chanPtr->outputEncodingState = NULL; + chanPtr->outputEncodingFlags = TCL_ENCODING_START; + chanPtr->flags &= ~CHANNEL_NEED_MORE_DATA; + UpdateInterest(chanPtr); + } else if ((len > 2) && (optionName[1] == 'e') && + (strncmp(optionName, "-eofchar", len) == 0)) { + if (Tcl_SplitList(interp, newValue, &argc, &argv) == TCL_ERROR) { + return TCL_ERROR; + } + if (argc == 0) { + chanPtr->inEofChar = 0; + chanPtr->outEofChar = 0; + } else if (argc == 1) { + if (chanPtr->flags & TCL_WRITABLE) { + chanPtr->outEofChar = (int) argv[0][0]; + } + if (chanPtr->flags & TCL_READABLE) { + chanPtr->inEofChar = (int) argv[0][0]; + } + } else if (argc != 2) { + if (interp) { + Tcl_AppendResult(interp, + "bad value for -eofchar: should be a list of one or", + " two elements", (char *) NULL); + } + ckfree((char *) argv); + return TCL_ERROR; + } else { + if (chanPtr->flags & TCL_READABLE) { + chanPtr->inEofChar = (int) argv[0][0]; + } + if (chanPtr->flags & TCL_WRITABLE) { + chanPtr->outEofChar = (int) argv[1][0]; + } + } + if (argv != (char **) NULL) { + ckfree((char *) argv); + } + return TCL_OK; + } else if ((len > 1) && (optionName[1] == 't') && + (strncmp(optionName, "-translation", len) == 0)) { + char *readMode, *writeMode; + + if (Tcl_SplitList(interp, newValue, &argc, &argv) == TCL_ERROR) { + return TCL_ERROR; + } + + if (argc == 1) { + readMode = (chanPtr->flags & TCL_READABLE) ? argv[0] : NULL; + writeMode = (chanPtr->flags & TCL_WRITABLE) ? argv[0] : NULL; + } else if (argc == 2) { + readMode = (chanPtr->flags & TCL_READABLE) ? argv[0] : NULL; + writeMode = (chanPtr->flags & TCL_WRITABLE) ? argv[1] : NULL; + } else { + if (interp) { + Tcl_AppendResult(interp, + "bad value for -translation: must be a one or two", + " element list", (char *) NULL); + } + ckfree((char *) argv); + return TCL_ERROR; + } + + if (readMode) { + if (*readMode == '\0') { + newMode = chanPtr->inputTranslation; + } else if (strcmp(readMode, "auto") == 0) { + newMode = TCL_TRANSLATE_AUTO; + } else if (strcmp(readMode, "binary") == 0) { + newMode = TCL_TRANSLATE_LF; + chanPtr->inEofChar = 0; + Tcl_FreeEncoding(chanPtr->encoding); + chanPtr->encoding = NULL; + } else if (strcmp(readMode, "lf") == 0) { + newMode = TCL_TRANSLATE_LF; + } else if (strcmp(readMode, "cr") == 0) { + newMode = TCL_TRANSLATE_CR; + } else if (strcmp(readMode, "crlf") == 0) { + newMode = TCL_TRANSLATE_CRLF; + } else if (strcmp(readMode, "platform") == 0) { + newMode = TCL_PLATFORM_TRANSLATION; + } else { + if (interp) { + Tcl_AppendResult(interp, + "bad value for -translation: ", + "must be one of auto, binary, cr, lf, crlf,", + " or platform", (char *) NULL); + } + ckfree((char *) argv); + return TCL_ERROR; + } + + /* + * Reset the EOL flags since we need to look at any buffered + * data to see if the new translation mode allows us to + * complete the line. + */ + + if (newMode != chanPtr->inputTranslation) { + chanPtr->inputTranslation = (Tcl_EolTranslation) newMode; + chanPtr->flags &= ~(INPUT_SAW_CR); + chanPtr->flags &= ~(CHANNEL_NEED_MORE_DATA); + UpdateInterest(chanPtr); + } + } + if (writeMode) { + if (*writeMode == '\0') { + /* Do nothing. */ + } else if (strcmp(writeMode, "auto") == 0) { + /* + * This is a hack to get TCP sockets to produce output + * in CRLF mode if they are being set into AUTO mode. + * A better solution for achieving this effect will be + * coded later. + */ + + if (strcmp(chanPtr->typePtr->typeName, "tcp") == 0) { + chanPtr->outputTranslation = TCL_TRANSLATE_CRLF; + } else { + chanPtr->outputTranslation = TCL_PLATFORM_TRANSLATION; + } + } else if (strcmp(writeMode, "binary") == 0) { + chanPtr->outEofChar = 0; + chanPtr->outputTranslation = TCL_TRANSLATE_LF; + Tcl_FreeEncoding(chanPtr->encoding); + chanPtr->encoding = NULL; + } else if (strcmp(writeMode, "lf") == 0) { + chanPtr->outputTranslation = TCL_TRANSLATE_LF; + } else if (strcmp(writeMode, "cr") == 0) { + chanPtr->outputTranslation = TCL_TRANSLATE_CR; + } else if (strcmp(writeMode, "crlf") == 0) { + chanPtr->outputTranslation = TCL_TRANSLATE_CRLF; + } else if (strcmp(writeMode, "platform") == 0) { + chanPtr->outputTranslation = TCL_PLATFORM_TRANSLATION; + } else { + if (interp) { + Tcl_AppendResult(interp, + "bad value for -translation: ", + "must be one of auto, binary, cr, lf, crlf,", + " or platform", (char *) NULL); + } + ckfree((char *) argv); + return TCL_ERROR; + } + } + ckfree((char *) argv); + return TCL_OK; + } else if (chanPtr->typePtr->setOptionProc != NULL) { + return (*chanPtr->typePtr->setOptionProc)(chanPtr->instanceData, + interp, optionName, newValue); + } else { + return Tcl_BadChannelOption(interp, optionName, (char *) NULL); + } + + /* + * If bufsize changes, need to get rid of old utility buffer. + */ + + if (chanPtr->saveInBufPtr != NULL) { + RecycleBuffer(chanPtr, chanPtr->saveInBufPtr, 1); + chanPtr->saveInBufPtr = NULL; + } + if (chanPtr->inQueueHead != NULL) { + if ((chanPtr->inQueueHead->nextPtr == NULL) + && (chanPtr->inQueueHead->nextAdded == + chanPtr->inQueueHead->nextRemoved)) { + RecycleBuffer(chanPtr, chanPtr->inQueueHead, 1); + chanPtr->inQueueHead = NULL; + chanPtr->inQueueTail = NULL; + } + } + + /* + * If encoding or bufsize changes, need to update output staging buffer. + */ + + if (chanPtr->outputStage != NULL) { + ckfree((char *) chanPtr->outputStage); + chanPtr->outputStage = NULL; + } + if ((chanPtr->encoding != NULL) && (chanPtr->flags & TCL_WRITABLE)) { + chanPtr->outputStage = (char *) + ckalloc((unsigned) (chanPtr->bufSize + 2)); + } + return TCL_OK; +} + +/* + *---------------------------------------------------------------------- + * + * CleanupChannelHandlers -- + * + * Removes channel handlers that refer to the supplied interpreter, + * so that if the actual channel is not closed now, these handlers + * will not run on subsequent events on the channel. This would be + * erroneous, because the interpreter no longer has a reference to + * this channel. + * + * Results: + * None. + * + * Side effects: + * Removes channel handlers. + * + *---------------------------------------------------------------------- + */ + +static void +CleanupChannelHandlers(interp, chanPtr) + Tcl_Interp *interp; + Channel *chanPtr; +{ + EventScriptRecord *sPtr, *prevPtr, *nextPtr; + + /* + * Remove fileevent records on this channel that refer to the + * given interpreter. + */ + + for (sPtr = chanPtr->scriptRecordPtr, + prevPtr = (EventScriptRecord *) NULL; + sPtr != (EventScriptRecord *) NULL; + sPtr = nextPtr) { + nextPtr = sPtr->nextPtr; + if (sPtr->interp == interp) { + if (prevPtr == (EventScriptRecord *) NULL) { + chanPtr->scriptRecordPtr = nextPtr; + } else { + prevPtr->nextPtr = nextPtr; + } + + Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, + ChannelEventScriptInvoker, (ClientData) sPtr); + + Tcl_DecrRefCount(sPtr->scriptPtr); + ckfree((char *) sPtr); + } else { + prevPtr = sPtr; + } + } +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_NotifyChannel -- + * + * This procedure is called by a channel driver when a driver + * detects an event on a channel. This procedure is responsible + * for actually handling the event by invoking any channel + * handler callbacks. + * + * Results: + * None. + * + * Side effects: + * Whatever the channel handler callback procedure does. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_NotifyChannel(channel, mask) + Tcl_Channel channel; /* Channel that detected an event. */ + int mask; /* OR'ed combination of TCL_READABLE, + * TCL_WRITABLE, or TCL_EXCEPTION: indicates + * which events were detected. */ +{ + Channel *chanPtr = (Channel *) channel; + ChannelHandler *chPtr; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + NextChannelHandler nh; + + /* + * Preserve the channel struct in case the script closes it. + */ + + Tcl_Preserve((ClientData) channel); + + /* + * If we are flushing in the background, be sure to call FlushChannel + * for writable events. Note that we have to discard the writable + * event so we don't call any write handlers before the flush is + * complete. + */ + + if ((chanPtr->flags & BG_FLUSH_SCHEDULED) && (mask & TCL_WRITABLE)) { + FlushChannel(NULL, chanPtr, 1); + mask &= ~TCL_WRITABLE; + } + + /* + * Add this invocation to the list of recursive invocations of + * ChannelHandlerEventProc. + */ + + nh.nextHandlerPtr = (ChannelHandler *) NULL; + nh.nestedHandlerPtr = tsdPtr->nestedHandlerPtr; + tsdPtr->nestedHandlerPtr = &nh; + + for (chPtr = chanPtr->chPtr; chPtr != (ChannelHandler *) NULL; ) { + + /* + * If this channel handler is interested in any of the events that + * have occurred on the channel, invoke its procedure. + */ + + if ((chPtr->mask & mask) != 0) { + nh.nextHandlerPtr = chPtr->nextPtr; + (*(chPtr->proc))(chPtr->clientData, mask); + chPtr = nh.nextHandlerPtr; + } else { + chPtr = chPtr->nextPtr; + } + } + + /* + * Update the notifier interest, since it may have changed after + * invoking event handlers. + */ + + if (chanPtr->typePtr != NULL) { + UpdateInterest(chanPtr); + } + + Tcl_Release((ClientData) channel); + + tsdPtr->nestedHandlerPtr = nh.nestedHandlerPtr; +} + +/* + *---------------------------------------------------------------------- + * + * UpdateInterest -- + * + * Arrange for the notifier to call us back at appropriate times + * based on the current state of the channel. + * + * Results: + * None. + * + * Side effects: + * May schedule a timer or driver handler. + * + *---------------------------------------------------------------------- + */ + +static void +UpdateInterest(chanPtr) + Channel *chanPtr; /* Channel to update. */ +{ + int mask = chanPtr->interestMask; + + /* + * If there are flushed buffers waiting to be written, then + * we need to watch for the channel to become writable. + */ + + if (chanPtr->flags & BG_FLUSH_SCHEDULED) { + mask |= TCL_WRITABLE; + } + + /* + * If there is data in the input queue, and we aren't waiting for more + * data, then we need to schedule a timer so we don't block in the + * notifier. Also, cancel the read interest so we don't get duplicate + * events. + */ + + if (mask & TCL_READABLE) { + if (!(chanPtr->flags & CHANNEL_NEED_MORE_DATA) + && (chanPtr->inQueueHead != (ChannelBuffer *) NULL) + && (chanPtr->inQueueHead->nextRemoved < + chanPtr->inQueueHead->nextAdded)) { + mask &= ~TCL_READABLE; + if (!chanPtr->timer) { + chanPtr->timer = Tcl_CreateTimerHandler(0, ChannelTimerProc, + (ClientData) chanPtr); + } + } + } + (chanPtr->typePtr->watchProc)(chanPtr->instanceData, mask); +} + +/* + *---------------------------------------------------------------------- + * + * ChannelTimerProc -- + * + * Timer handler scheduled by UpdateInterest to monitor the + * channel buffers until they are empty. + * + * Results: + * None. + * + * Side effects: + * May invoke channel handlers. + * + *---------------------------------------------------------------------- + */ + +static void +ChannelTimerProc(clientData) + ClientData clientData; +{ + Channel *chanPtr = (Channel *) clientData; + + if (!(chanPtr->flags & CHANNEL_NEED_MORE_DATA) + && (chanPtr->interestMask & TCL_READABLE) + && (chanPtr->inQueueHead != (ChannelBuffer *) NULL) + && (chanPtr->inQueueHead->nextRemoved < + chanPtr->inQueueHead->nextAdded)) { + /* + * Restart the timer in case a channel handler reenters the + * event loop before UpdateInterest gets called by Tcl_NotifyChannel. + */ + + chanPtr->timer = Tcl_CreateTimerHandler(0, ChannelTimerProc, + (ClientData) chanPtr); + Tcl_NotifyChannel((Tcl_Channel)chanPtr, TCL_READABLE); + + } else { + chanPtr->timer = NULL; + UpdateInterest(chanPtr); + } +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_CreateChannelHandler -- + * + * Arrange for a given procedure to be invoked whenever the + * channel indicated by the chanPtr arg becomes readable or + * writable. + * + * Results: + * None. + * + * Side effects: + * From now on, whenever the I/O channel given by chanPtr becomes + * ready in the way indicated by mask, proc will be invoked. + * See the manual entry for details on the calling sequence + * to proc. If there is already an event handler for chan, proc + * and clientData, then the mask will be updated. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_CreateChannelHandler(chan, mask, proc, clientData) + Tcl_Channel chan; /* The channel to create the handler for. */ + int mask; /* OR'ed combination of TCL_READABLE, + * TCL_WRITABLE, and TCL_EXCEPTION: + * indicates conditions under which + * proc should be called. Use 0 to + * disable a registered handler. */ + Tcl_ChannelProc *proc; /* Procedure to call for each + * selected event. */ + ClientData clientData; /* Arbitrary data to pass to proc. */ +{ + ChannelHandler *chPtr; + Channel *chanPtr; + + chanPtr = (Channel *) chan; + + /* + * Check whether this channel handler is not already registered. If + * it is not, create a new record, else reuse existing record (smash + * current values). + */ + + for (chPtr = chanPtr->chPtr; + chPtr != (ChannelHandler *) NULL; + chPtr = chPtr->nextPtr) { + if ((chPtr->chanPtr == chanPtr) && (chPtr->proc == proc) && + (chPtr->clientData == clientData)) { + break; + } + } + if (chPtr == (ChannelHandler *) NULL) { + chPtr = (ChannelHandler *) ckalloc((unsigned) sizeof(ChannelHandler)); + chPtr->mask = 0; + chPtr->proc = proc; + chPtr->clientData = clientData; + chPtr->chanPtr = chanPtr; + chPtr->nextPtr = chanPtr->chPtr; + chanPtr->chPtr = chPtr; + } + + /* + * The remainder of the initialization below is done regardless of + * whether or not this is a new record or a modification of an old + * one. + */ + + chPtr->mask = mask; + + /* + * Recompute the interest mask for the channel - this call may actually + * be disabling an existing handler. + */ + + chanPtr->interestMask = 0; + for (chPtr = chanPtr->chPtr; + chPtr != (ChannelHandler *) NULL; + chPtr = chPtr->nextPtr) { + chanPtr->interestMask |= chPtr->mask; + } + + UpdateInterest(chanPtr); +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_DeleteChannelHandler -- + * + * Cancel a previously arranged callback arrangement for an IO + * channel. + * + * Results: + * None. + * + * Side effects: + * If a callback was previously registered for this chan, proc and + * clientData , it is removed and the callback will no longer be called + * when the channel becomes ready for IO. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_DeleteChannelHandler(chan, proc, clientData) + Tcl_Channel chan; /* The channel for which to remove the + * callback. */ + Tcl_ChannelProc *proc; /* The procedure in the callback to delete. */ + ClientData clientData; /* The client data in the callback + * to delete. */ + +{ + ChannelHandler *chPtr, *prevChPtr; + Channel *chanPtr; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + NextChannelHandler *nhPtr; + + chanPtr = (Channel *) chan; + + /* + * Find the entry and the previous one in the list. + */ + + for (prevChPtr = (ChannelHandler *) NULL, chPtr = chanPtr->chPtr; + chPtr != (ChannelHandler *) NULL; + chPtr = chPtr->nextPtr) { + if ((chPtr->chanPtr == chanPtr) && (chPtr->clientData == clientData) + && (chPtr->proc == proc)) { + break; + } + prevChPtr = chPtr; + } + + /* + * If not found, return without doing anything. + */ + + if (chPtr == (ChannelHandler *) NULL) { + return; + } + + /* + * If ChannelHandlerEventProc is about to process this handler, tell it to + * process the next one instead - we are going to delete *this* one. + */ + + for (nhPtr = tsdPtr->nestedHandlerPtr; + nhPtr != (NextChannelHandler *) NULL; + nhPtr = nhPtr->nestedHandlerPtr) { + if (nhPtr->nextHandlerPtr == chPtr) { + nhPtr->nextHandlerPtr = chPtr->nextPtr; + } + } + + /* + * Splice it out of the list of channel handlers. + */ + + if (prevChPtr == (ChannelHandler *) NULL) { + chanPtr->chPtr = chPtr->nextPtr; + } else { + prevChPtr->nextPtr = chPtr->nextPtr; + } + ckfree((char *) chPtr); + + /* + * Recompute the interest list for the channel, so that infinite loops + * will not result if Tcl_DeleteChannelHandler is called inside an + * event. + */ + + chanPtr->interestMask = 0; + for (chPtr = chanPtr->chPtr; + chPtr != (ChannelHandler *) NULL; + chPtr = chPtr->nextPtr) { + chanPtr->interestMask |= chPtr->mask; + } + + UpdateInterest(chanPtr); +} + +/* + *---------------------------------------------------------------------- + * + * DeleteScriptRecord -- + * + * Delete a script record for this combination of channel, interp + * and mask. + * + * Results: + * None. + * + * Side effects: + * Deletes a script record and cancels a channel event handler. + * + *---------------------------------------------------------------------- + */ + +static void +DeleteScriptRecord(interp, chanPtr, mask) + Tcl_Interp *interp; /* Interpreter in which script was to be + * executed. */ + Channel *chanPtr; /* The channel for which to delete the + * script record (if any). */ + int mask; /* Events in mask must exactly match mask + * of script to delete. */ +{ + EventScriptRecord *esPtr, *prevEsPtr; + + for (esPtr = chanPtr->scriptRecordPtr, + prevEsPtr = (EventScriptRecord *) NULL; + esPtr != (EventScriptRecord *) NULL; + prevEsPtr = esPtr, esPtr = esPtr->nextPtr) { + if ((esPtr->interp == interp) && (esPtr->mask == mask)) { + if (esPtr == chanPtr->scriptRecordPtr) { + chanPtr->scriptRecordPtr = esPtr->nextPtr; + } else { + prevEsPtr->nextPtr = esPtr->nextPtr; + } + + Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, + ChannelEventScriptInvoker, (ClientData) esPtr); + + Tcl_DecrRefCount(esPtr->scriptPtr); + ckfree((char *) esPtr); + + break; + } + } +} + +/* + *---------------------------------------------------------------------- + * + * CreateScriptRecord -- + * + * Creates a record to store a script to be executed when a specific + * event fires on a specific channel. + * + * Results: + * None. + * + * Side effects: + * Causes the script to be stored for later execution. + * + *---------------------------------------------------------------------- + */ + +static void +CreateScriptRecord(interp, chanPtr, mask, scriptPtr) + Tcl_Interp *interp; /* Interpreter in which to execute + * the stored script. */ + Channel *chanPtr; /* Channel for which script is to + * be stored. */ + int mask; /* Set of events for which script + * will be invoked. */ + Tcl_Obj *scriptPtr; /* Pointer to script object. */ +{ + EventScriptRecord *esPtr; + + for (esPtr = chanPtr->scriptRecordPtr; + esPtr != (EventScriptRecord *) NULL; + esPtr = esPtr->nextPtr) { + if ((esPtr->interp == interp) && (esPtr->mask == mask)) { + Tcl_DecrRefCount(esPtr->scriptPtr); + esPtr->scriptPtr = (Tcl_Obj *) NULL; + break; + } + } + if (esPtr == (EventScriptRecord *) NULL) { + esPtr = (EventScriptRecord *) ckalloc((unsigned) + sizeof(EventScriptRecord)); + Tcl_CreateChannelHandler((Tcl_Channel) chanPtr, mask, + ChannelEventScriptInvoker, (ClientData) esPtr); + esPtr->nextPtr = chanPtr->scriptRecordPtr; + chanPtr->scriptRecordPtr = esPtr; + } + esPtr->chanPtr = chanPtr; + esPtr->interp = interp; + esPtr->mask = mask; + Tcl_IncrRefCount(scriptPtr); + esPtr->scriptPtr = scriptPtr; +} + +/* + *---------------------------------------------------------------------- + * + * ChannelEventScriptInvoker -- + * + * Invokes a script scheduled by "fileevent" for when the channel + * becomes ready for IO. This function is invoked by the channel + * handler which was created by the Tcl "fileevent" command. + * + * Results: + * None. + * + * Side effects: + * Whatever the script does. + * + *---------------------------------------------------------------------- + */ + +static void +ChannelEventScriptInvoker(clientData, mask) + ClientData clientData; /* The script+interp record. */ + int mask; /* Not used. */ +{ + Tcl_Interp *interp; /* Interpreter in which to eval the script. */ + Channel *chanPtr; /* The channel for which this handler is + * registered. */ + EventScriptRecord *esPtr; /* The event script + interpreter to eval it + * in. */ + int result; /* Result of call to eval script. */ + + esPtr = (EventScriptRecord *) clientData; + + chanPtr = esPtr->chanPtr; + mask = esPtr->mask; + interp = esPtr->interp; + + /* + * We must preserve the interpreter so we can report errors on it + * later. Note that we do not need to preserve the channel because + * that is done by Tcl_NotifyChannel before calling channel handlers. + */ + + Tcl_Preserve((ClientData) interp); + result = Tcl_EvalObjEx(interp, esPtr->scriptPtr, TCL_EVAL_GLOBAL); + + /* + * On error, cause a background error and remove the channel handler + * and the script record. + * + * NOTE: Must delete channel handler before causing the background error + * because the background error may want to reinstall the handler. + */ + + if (result != TCL_OK) { + if (chanPtr->typePtr != NULL) { + DeleteScriptRecord(interp, chanPtr, mask); + } + Tcl_BackgroundError(interp); + } + Tcl_Release((ClientData) interp); +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_FileEventObjCmd -- + * + * This procedure implements the "fileevent" Tcl command. See the + * user documentation for details on what it does. This command is + * based on the Tk command "fileevent" which in turn is based on work + * contributed by Mark Diekhans. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * May create a channel handler for the specified channel. + * + *---------------------------------------------------------------------- + */ + + /* ARGSUSED */ +int +Tcl_FileEventObjCmd(clientData, interp, objc, objv) + ClientData clientData; /* Not used. */ + Tcl_Interp *interp; /* Interpreter in which the channel + * for which to create the handler + * is found. */ + int objc; /* Number of arguments. */ + Tcl_Obj *CONST objv[]; /* Argument objects. */ +{ + Channel *chanPtr; /* The channel to create + * the handler for. */ + Tcl_Channel chan; /* The opaque type for the channel. */ + char *chanName; + int modeIndex; /* Index of mode argument. */ + int mask; + static char *modeOptions[] = {"readable", "writable", NULL}; + static int maskArray[] = {TCL_READABLE, TCL_WRITABLE}; + + if ((objc != 3) && (objc != 4)) { + Tcl_WrongNumArgs(interp, 1, objv, "channelId event ?script?"); + return TCL_ERROR; + } + if (Tcl_GetIndexFromObj(interp, objv[2], modeOptions, "event name", 0, + &modeIndex) != TCL_OK) { + return TCL_ERROR; + } + mask = maskArray[modeIndex]; + + chanName = Tcl_GetString(objv[1]); + chan = Tcl_GetChannel(interp, chanName, NULL); + if (chan == (Tcl_Channel) NULL) { + return TCL_ERROR; + } + chanPtr = (Channel *) chan; + if ((chanPtr->flags & mask) == 0) { + Tcl_AppendResult(interp, "channel is not ", + (mask == TCL_READABLE) ? "readable" : "writable", + (char *) NULL); + return TCL_ERROR; + } + + /* + * If we are supposed to return the script, do so. + */ + + if (objc == 3) { + EventScriptRecord *esPtr; + for (esPtr = chanPtr->scriptRecordPtr; + esPtr != (EventScriptRecord *) NULL; + esPtr = esPtr->nextPtr) { + if ((esPtr->interp == interp) && (esPtr->mask == mask)) { + Tcl_SetObjResult(interp, esPtr->scriptPtr); + break; + } + } + return TCL_OK; + } + + /* + * If we are supposed to delete a stored script, do so. + */ + + if (*(Tcl_GetString(objv[3])) == '\0') { + DeleteScriptRecord(interp, chanPtr, mask); + return TCL_OK; + } + + /* + * Make the script record that will link between the event and the + * script to invoke. This also creates a channel event handler which + * will evaluate the script in the supplied interpreter. + */ + + CreateScriptRecord(interp, chanPtr, mask, objv[3]); + + return TCL_OK; +} + +/* + *---------------------------------------------------------------------- + * + * TclTestChannelCmd -- + * + * Implements the Tcl "testchannel" debugging command and its + * subcommands. This is part of the testing environment but must be + * in this file instead of tclTest.c because it needs access to the + * fields of struct Channel. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + + /* ARGSUSED */ +int +TclTestChannelCmd(clientData, interp, argc, argv) + ClientData clientData; /* Not used. */ + Tcl_Interp *interp; /* Interpreter for result. */ + int argc; /* Count of additional args. */ + char **argv; /* Additional arg strings. */ +{ + char *cmdName; /* Sub command. */ + Tcl_HashTable *hTblPtr; /* Hash table of channels. */ + Tcl_HashSearch hSearch; /* Search variable. */ + Tcl_HashEntry *hPtr; /* Search variable. */ + Channel *chanPtr; /* The actual channel. */ + Tcl_Channel chan; /* The opaque type. */ + size_t len; /* Length of subcommand string. */ + int IOQueued; /* How much IO is queued inside channel? */ + ChannelBuffer *bufPtr; /* For iterating over queued IO. */ + char buf[TCL_INTEGER_SPACE];/* For sprintf. */ + + if (argc < 2) { + Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], + " subcommand ?additional args..?\"", (char *) NULL); + return TCL_ERROR; + } + cmdName = argv[1]; + len = strlen(cmdName); + + chanPtr = (Channel *) NULL; + + if (argc > 2) { + chan = Tcl_GetChannel(interp, argv[2], NULL); + if (chan == (Tcl_Channel) NULL) { + return TCL_ERROR; + } + chanPtr = (Channel *) chan; + } + + + if ((cmdName[0] == 'i') && (strncmp(cmdName, "info", len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], + " info channelName\"", (char *) NULL); + return TCL_ERROR; + } + Tcl_AppendElement(interp, argv[2]); + Tcl_AppendElement(interp, chanPtr->typePtr->typeName); + if (chanPtr->flags & TCL_READABLE) { + Tcl_AppendElement(interp, "read"); + } else { + Tcl_AppendElement(interp, ""); + } + if (chanPtr->flags & TCL_WRITABLE) { + Tcl_AppendElement(interp, "write"); + } else { + Tcl_AppendElement(interp, ""); + } + if (chanPtr->flags & CHANNEL_NONBLOCKING) { + Tcl_AppendElement(interp, "nonblocking"); + } else { + Tcl_AppendElement(interp, "blocking"); + } + if (chanPtr->flags & CHANNEL_LINEBUFFERED) { + Tcl_AppendElement(interp, "line"); + } else if (chanPtr->flags & CHANNEL_UNBUFFERED) { + Tcl_AppendElement(interp, "none"); + } else { + Tcl_AppendElement(interp, "full"); + } + if (chanPtr->flags & BG_FLUSH_SCHEDULED) { + Tcl_AppendElement(interp, "async_flush"); + } else { + Tcl_AppendElement(interp, ""); + } + if (chanPtr->flags & CHANNEL_EOF) { + Tcl_AppendElement(interp, "eof"); + } else { + Tcl_AppendElement(interp, ""); + } + if (chanPtr->flags & CHANNEL_BLOCKED) { + Tcl_AppendElement(interp, "blocked"); + } else { + Tcl_AppendElement(interp, "unblocked"); + } + if (chanPtr->inputTranslation == TCL_TRANSLATE_AUTO) { + Tcl_AppendElement(interp, "auto"); + if (chanPtr->flags & INPUT_SAW_CR) { + Tcl_AppendElement(interp, "saw_cr"); + } else { + Tcl_AppendElement(interp, ""); + } + } else if (chanPtr->inputTranslation == TCL_TRANSLATE_LF) { + Tcl_AppendElement(interp, "lf"); + Tcl_AppendElement(interp, ""); + } else if (chanPtr->inputTranslation == TCL_TRANSLATE_CR) { + Tcl_AppendElement(interp, "cr"); + Tcl_AppendElement(interp, ""); + } else if (chanPtr->inputTranslation == TCL_TRANSLATE_CRLF) { + Tcl_AppendElement(interp, "crlf"); + if (chanPtr->flags & INPUT_SAW_CR) { + Tcl_AppendElement(interp, "queued_cr"); + } else { + Tcl_AppendElement(interp, ""); + } + } + if (chanPtr->outputTranslation == TCL_TRANSLATE_AUTO) { + Tcl_AppendElement(interp, "auto"); + } else if (chanPtr->outputTranslation == TCL_TRANSLATE_LF) { + Tcl_AppendElement(interp, "lf"); + } else if (chanPtr->outputTranslation == TCL_TRANSLATE_CR) { + Tcl_AppendElement(interp, "cr"); + } else if (chanPtr->outputTranslation == TCL_TRANSLATE_CRLF) { + Tcl_AppendElement(interp, "crlf"); + } + for (IOQueued = 0, bufPtr = chanPtr->inQueueHead; + bufPtr != (ChannelBuffer *) NULL; + bufPtr = bufPtr->nextPtr) { + IOQueued += bufPtr->nextAdded - bufPtr->nextRemoved; + } + TclFormatInt(buf, IOQueued); + Tcl_AppendElement(interp, buf); + + IOQueued = 0; + if (chanPtr->curOutPtr != (ChannelBuffer *) NULL) { + IOQueued = chanPtr->curOutPtr->nextAdded - + chanPtr->curOutPtr->nextRemoved; + } + for (bufPtr = chanPtr->outQueueHead; + bufPtr != (ChannelBuffer *) NULL; + bufPtr = bufPtr->nextPtr) { + IOQueued += (bufPtr->nextAdded - bufPtr->nextRemoved); + } + TclFormatInt(buf, IOQueued); + Tcl_AppendElement(interp, buf); + + TclFormatInt(buf, Tcl_Tell((Tcl_Channel) chanPtr)); + Tcl_AppendElement(interp, buf); + + TclFormatInt(buf, chanPtr->refCount); + Tcl_AppendElement(interp, buf); + + return TCL_OK; + } + + if ((cmdName[0] == 'i') && + (strncmp(cmdName, "inputbuffered", len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "channel name required", + (char *) NULL); + return TCL_ERROR; + } + + for (IOQueued = 0, bufPtr = chanPtr->inQueueHead; + bufPtr != (ChannelBuffer *) NULL; + bufPtr = bufPtr->nextPtr) { + IOQueued += bufPtr->nextAdded - bufPtr->nextRemoved; + } + TclFormatInt(buf, IOQueued); + Tcl_AppendResult(interp, buf, (char *) NULL); + return TCL_OK; + } + + if ((cmdName[0] == 'm') && (strncmp(cmdName, "mode", len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "channel name required", + (char *) NULL); + return TCL_ERROR; + } + + if (chanPtr->flags & TCL_READABLE) { + Tcl_AppendElement(interp, "read"); + } else { + Tcl_AppendElement(interp, ""); + } + if (chanPtr->flags & TCL_WRITABLE) { + Tcl_AppendElement(interp, "write"); + } else { + Tcl_AppendElement(interp, ""); + } + return TCL_OK; + } + + if ((cmdName[0] == 'n') && (strncmp(cmdName, "name", len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "channel name required", + (char *) NULL); + return TCL_ERROR; + } + Tcl_AppendResult(interp, chanPtr->channelName, (char *) NULL); + return TCL_OK; + } + + if ((cmdName[0] == 'o') && (strncmp(cmdName, "open", len) == 0)) { + hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); + if (hTblPtr == (Tcl_HashTable *) NULL) { + return TCL_OK; + } + for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); + hPtr != (Tcl_HashEntry *) NULL; + hPtr = Tcl_NextHashEntry(&hSearch)) { + Tcl_AppendElement(interp, Tcl_GetHashKey(hTblPtr, hPtr)); + } + return TCL_OK; + } + + if ((cmdName[0] == 'o') && + (strncmp(cmdName, "outputbuffered", len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "channel name required", + (char *) NULL); + return TCL_ERROR; + } + + IOQueued = 0; + if (chanPtr->curOutPtr != (ChannelBuffer *) NULL) { + IOQueued = chanPtr->curOutPtr->nextAdded - + chanPtr->curOutPtr->nextRemoved; + } + for (bufPtr = chanPtr->outQueueHead; + bufPtr != (ChannelBuffer *) NULL; + bufPtr = bufPtr->nextPtr) { + IOQueued += (bufPtr->nextAdded - bufPtr->nextRemoved); + } + TclFormatInt(buf, IOQueued); + Tcl_AppendResult(interp, buf, (char *) NULL); + return TCL_OK; + } + + if ((cmdName[0] == 'q') && + (strncmp(cmdName, "queuedcr", len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "channel name required", + (char *) NULL); + return TCL_ERROR; + } + + Tcl_AppendResult(interp, + (chanPtr->flags & INPUT_SAW_CR) ? "1" : "0", + (char *) NULL); + return TCL_OK; + } + + if ((cmdName[0] == 'r') && (strncmp(cmdName, "readable", len) == 0)) { + hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); + if (hTblPtr == (Tcl_HashTable *) NULL) { + return TCL_OK; + } + for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); + hPtr != (Tcl_HashEntry *) NULL; + hPtr = Tcl_NextHashEntry(&hSearch)) { + chanPtr = (Channel *) Tcl_GetHashValue(hPtr); + if (chanPtr->flags & TCL_READABLE) { + Tcl_AppendElement(interp, Tcl_GetHashKey(hTblPtr, hPtr)); + } + } + return TCL_OK; + } + + if ((cmdName[0] == 'r') && (strncmp(cmdName, "refcount", len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "channel name required", + (char *) NULL); + return TCL_ERROR; + } + + TclFormatInt(buf, chanPtr->refCount); + Tcl_AppendResult(interp, buf, (char *) NULL); + return TCL_OK; + } + + if ((cmdName[0] == 't') && (strncmp(cmdName, "type", len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "channel name required", + (char *) NULL); + return TCL_ERROR; + } + Tcl_AppendResult(interp, chanPtr->typePtr->typeName, (char *) NULL); + return TCL_OK; + } + + if ((cmdName[0] == 'w') && (strncmp(cmdName, "writable", len) == 0)) { + hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); + if (hTblPtr == (Tcl_HashTable *) NULL) { + return TCL_OK; + } + for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); + hPtr != (Tcl_HashEntry *) NULL; + hPtr = Tcl_NextHashEntry(&hSearch)) { + chanPtr = (Channel *) Tcl_GetHashValue(hPtr); + if (chanPtr->flags & TCL_WRITABLE) { + Tcl_AppendElement(interp, Tcl_GetHashKey(hTblPtr, hPtr)); + } + } + return TCL_OK; + } + + Tcl_AppendResult(interp, "bad option \"", cmdName, "\": should be ", + "info, open, readable, or writable", + (char *) NULL); + return TCL_ERROR; +} + +/* + *---------------------------------------------------------------------- + * + * TclTestChannelEventCmd -- + * + * This procedure implements the "testchannelevent" command. It is + * used to test the Tcl channel event mechanism. It is present in + * this file instead of tclTest.c because it needs access to the + * internal structure of the channel. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * Creates, deletes and returns channel event handlers. + * + *---------------------------------------------------------------------- + */ + + /* ARGSUSED */ +int +TclTestChannelEventCmd(dummy, interp, argc, argv) + ClientData dummy; /* Not used. */ + Tcl_Interp *interp; /* Current interpreter. */ + int argc; /* Number of arguments. */ + char **argv; /* Argument strings. */ +{ + Tcl_Obj *resultListPtr; + Channel *chanPtr; + EventScriptRecord *esPtr, *prevEsPtr, *nextEsPtr; + char *cmd; + int index, i, mask, len; + + if ((argc < 3) || (argc > 5)) { + Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], + " channelName cmd ?arg1? ?arg2?\"", (char *) NULL); + return TCL_ERROR; + } + chanPtr = (Channel *) Tcl_GetChannel(interp, argv[1], NULL); + if (chanPtr == (Channel *) NULL) { + return TCL_ERROR; + } + cmd = argv[2]; + len = strlen(cmd); + if ((cmd[0] == 'a') && (strncmp(cmd, "add", (unsigned) len) == 0)) { + if (argc != 5) { + Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], + " channelName add eventSpec script\"", (char *) NULL); + return TCL_ERROR; + } + if (strcmp(argv[3], "readable") == 0) { + mask = TCL_READABLE; + } else if (strcmp(argv[3], "writable") == 0) { + mask = TCL_WRITABLE; + } else if (strcmp(argv[3], "none") == 0) { + mask = 0; + } else { + Tcl_AppendResult(interp, "bad event name \"", argv[3], + "\": must be readable, writable, or none", (char *) NULL); + return TCL_ERROR; + } + + esPtr = (EventScriptRecord *) ckalloc((unsigned) + sizeof(EventScriptRecord)); + esPtr->nextPtr = chanPtr->scriptRecordPtr; + chanPtr->scriptRecordPtr = esPtr; + + esPtr->chanPtr = chanPtr; + esPtr->interp = interp; + esPtr->mask = mask; + esPtr->scriptPtr = Tcl_NewStringObj(argv[4], -1); + Tcl_IncrRefCount(esPtr->scriptPtr); + + Tcl_CreateChannelHandler((Tcl_Channel) chanPtr, mask, + ChannelEventScriptInvoker, (ClientData) esPtr); + + return TCL_OK; + } + + if ((cmd[0] == 'd') && (strncmp(cmd, "delete", (unsigned) len) == 0)) { + if (argc != 4) { + Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], + " channelName delete index\"", (char *) NULL); + return TCL_ERROR; + } + if (Tcl_GetInt(interp, argv[3], &index) == TCL_ERROR) { + return TCL_ERROR; + } + if (index < 0) { + Tcl_AppendResult(interp, "bad event index: ", argv[3], + ": must be nonnegative", (char *) NULL); + return TCL_ERROR; + } + for (i = 0, esPtr = chanPtr->scriptRecordPtr; + (i < index) && (esPtr != (EventScriptRecord *) NULL); + i++, esPtr = esPtr->nextPtr) { + /* Empty loop body. */ + } + if (esPtr == (EventScriptRecord *) NULL) { + Tcl_AppendResult(interp, "bad event index ", argv[3], + ": out of range", (char *) NULL); + return TCL_ERROR; + } + if (esPtr == chanPtr->scriptRecordPtr) { + chanPtr->scriptRecordPtr = esPtr->nextPtr; + } else { + for (prevEsPtr = chanPtr->scriptRecordPtr; + (prevEsPtr != (EventScriptRecord *) NULL) && + (prevEsPtr->nextPtr != esPtr); + prevEsPtr = prevEsPtr->nextPtr) { + /* Empty loop body. */ + } + if (prevEsPtr == (EventScriptRecord *) NULL) { + panic("TclTestChannelEventCmd: damaged event script list"); + } + prevEsPtr->nextPtr = esPtr->nextPtr; + } + Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, + ChannelEventScriptInvoker, (ClientData) esPtr); + Tcl_DecrRefCount(esPtr->scriptPtr); + ckfree((char *) esPtr); + + return TCL_OK; + } + + if ((cmd[0] == 'l') && (strncmp(cmd, "list", (unsigned) len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], + " channelName list\"", (char *) NULL); + return TCL_ERROR; + } + resultListPtr = Tcl_GetObjResult(interp); + for (esPtr = chanPtr->scriptRecordPtr; + esPtr != (EventScriptRecord *) NULL; + esPtr = esPtr->nextPtr) { + if (esPtr->mask) { + Tcl_ListObjAppendElement(interp, resultListPtr, Tcl_NewStringObj( + (esPtr->mask == TCL_READABLE) ? "readable" : "writable", -1)); + } else { + Tcl_ListObjAppendElement(interp, resultListPtr, + Tcl_NewStringObj("none", -1)); + } + Tcl_ListObjAppendElement(interp, resultListPtr, esPtr->scriptPtr); + } + Tcl_SetObjResult(interp, resultListPtr); + return TCL_OK; + } + + if ((cmd[0] == 'r') && (strncmp(cmd, "removeall", (unsigned) len) == 0)) { + if (argc != 3) { + Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], + " channelName removeall\"", (char *) NULL); + return TCL_ERROR; + } + for (esPtr = chanPtr->scriptRecordPtr; + esPtr != (EventScriptRecord *) NULL; + esPtr = nextEsPtr) { + nextEsPtr = esPtr->nextPtr; + Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, + ChannelEventScriptInvoker, (ClientData) esPtr); + Tcl_DecrRefCount(esPtr->scriptPtr); + ckfree((char *) esPtr); + } + chanPtr->scriptRecordPtr = (EventScriptRecord *) NULL; + return TCL_OK; + } + + if ((cmd[0] == 's') && (strncmp(cmd, "set", (unsigned) len) == 0)) { + if (argc != 5) { + Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], + " channelName delete index event\"", (char *) NULL); + return TCL_ERROR; + } + if (Tcl_GetInt(interp, argv[3], &index) == TCL_ERROR) { + return TCL_ERROR; + } + if (index < 0) { + Tcl_AppendResult(interp, "bad event index: ", argv[3], + ": must be nonnegative", (char *) NULL); + return TCL_ERROR; + } + for (i = 0, esPtr = chanPtr->scriptRecordPtr; + (i < index) && (esPtr != (EventScriptRecord *) NULL); + i++, esPtr = esPtr->nextPtr) { + /* Empty loop body. */ + } + if (esPtr == (EventScriptRecord *) NULL) { + Tcl_AppendResult(interp, "bad event index ", argv[3], + ": out of range", (char *) NULL); + return TCL_ERROR; + } + + if (strcmp(argv[4], "readable") == 0) { + mask = TCL_READABLE; + } else if (strcmp(argv[4], "writable") == 0) { + mask = TCL_WRITABLE; + } else if (strcmp(argv[4], "none") == 0) { + mask = 0; + } else { + Tcl_AppendResult(interp, "bad event name \"", argv[4], + "\": must be readable, writable, or none", (char *) NULL); + return TCL_ERROR; + } + esPtr->mask = mask; + Tcl_CreateChannelHandler((Tcl_Channel) chanPtr, mask, + ChannelEventScriptInvoker, (ClientData) esPtr); + return TCL_OK; + } + Tcl_AppendResult(interp, "bad command ", cmd, ", must be one of ", + "add, delete, list, set, or removeall", (char *) NULL); + return TCL_ERROR; +} + +/* + *---------------------------------------------------------------------- + * + * TclCopyChannel -- + * + * This routine copies data from one channel to another, either + * synchronously or asynchronously. If a command script is + * supplied, the operation runs in the background. The script + * is invoked when the copy completes. Otherwise the function + * waits until the copy is completed before returning. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * May schedule a background copy operation that causes both + * channels to be marked busy. + * + *---------------------------------------------------------------------- + */ + +int +TclCopyChannel(interp, inChan, outChan, toRead, cmdPtr) + Tcl_Interp *interp; /* Current interpreter. */ + Tcl_Channel inChan; /* Channel to read from. */ + Tcl_Channel outChan; /* Channel to write to. */ + int toRead; /* Amount of data to copy, or -1 for all. */ + Tcl_Obj *cmdPtr; /* Pointer to script to execute or NULL. */ +{ + Channel *inPtr = (Channel *) inChan; + Channel *outPtr = (Channel *) outChan; + int readFlags, writeFlags; + CopyState *csPtr; + int nonBlocking = (cmdPtr) ? CHANNEL_NONBLOCKING : 0; + + if (inPtr->csPtr) { + Tcl_AppendStringsToObj(Tcl_GetObjResult(interp), "channel \"", + Tcl_GetChannelName(inChan), "\" is busy", NULL); + return TCL_ERROR; + } + if (outPtr->csPtr) { + Tcl_AppendStringsToObj(Tcl_GetObjResult(interp), "channel \"", + Tcl_GetChannelName(outChan), "\" is busy", NULL); + return TCL_ERROR; + } + + readFlags = inPtr->flags; + writeFlags = outPtr->flags; + + /* + * Set up the blocking mode appropriately. Background copies need + * non-blocking channels. Foreground copies need blocking channels. + * If there is an error, restore the old blocking mode. + */ + + if (nonBlocking != (readFlags & CHANNEL_NONBLOCKING)) { + if (SetBlockMode(interp, inPtr, + nonBlocking ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING) + != TCL_OK) { + return TCL_ERROR; + } + } + if (inPtr != outPtr) { + if (nonBlocking != (writeFlags & CHANNEL_NONBLOCKING)) { + if (SetBlockMode(NULL, outPtr, + nonBlocking ? TCL_MODE_BLOCKING : TCL_MODE_NONBLOCKING) + != TCL_OK) { + if (nonBlocking != (readFlags & CHANNEL_NONBLOCKING)) { + SetBlockMode(NULL, inPtr, + (readFlags & CHANNEL_NONBLOCKING) + ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING); + return TCL_ERROR; + } + } + } + } + + /* + * Make sure the output side is unbuffered. + */ + + outPtr->flags = (outPtr->flags & ~(CHANNEL_LINEBUFFERED)) + | CHANNEL_UNBUFFERED; + + /* + * Allocate a new CopyState to maintain info about the current copy in + * progress. This structure will be deallocated when the copy is + * completed. + */ + + csPtr = (CopyState*) ckalloc(sizeof(CopyState) + inPtr->bufSize); + csPtr->bufSize = inPtr->bufSize; + csPtr->readPtr = inPtr; + csPtr->writePtr = outPtr; + csPtr->readFlags = readFlags; + csPtr->writeFlags = writeFlags; + csPtr->toRead = toRead; + csPtr->total = 0; + csPtr->interp = interp; + if (cmdPtr) { + Tcl_IncrRefCount(cmdPtr); + } + csPtr->cmdPtr = cmdPtr; + inPtr->csPtr = csPtr; + outPtr->csPtr = csPtr; + + /* + * Start copying data between the channels. + */ + + return CopyData(csPtr, 0); +} + +/* + *---------------------------------------------------------------------- + * + * CopyData -- + * + * This function implements the lowest level of the copying + * mechanism for TclCopyChannel. + * + * Results: + * Returns TCL_OK on success, else TCL_ERROR. + * + * Side effects: + * Moves data between channels, may create channel handlers. + * + *---------------------------------------------------------------------- + */ + +static int +CopyData(csPtr, mask) + CopyState *csPtr; /* State of copy operation. */ + int mask; /* Current channel event flags. */ +{ + Tcl_Interp *interp; + Tcl_Obj *cmdPtr, *errObj = NULL; + Tcl_Channel inChan, outChan; + int result = TCL_OK; + int size; + int total; + + inChan = (Tcl_Channel)csPtr->readPtr; + outChan = (Tcl_Channel)csPtr->writePtr; + interp = csPtr->interp; + cmdPtr = csPtr->cmdPtr; + + /* + * Copy the data the slow way, using the translation mechanism. + */ + + while (csPtr->toRead != 0) { + + /* + * Check for unreported background errors. + */ + + if (csPtr->readPtr->unreportedError != 0) { + Tcl_SetErrno(csPtr->readPtr->unreportedError); + csPtr->readPtr->unreportedError = 0; + goto readError; + } + if (csPtr->writePtr->unreportedError != 0) { + Tcl_SetErrno(csPtr->writePtr->unreportedError); + csPtr->writePtr->unreportedError = 0; + goto writeError; + } + + /* + * Read up to bufSize bytes. + */ + + if ((csPtr->toRead == -1) + || (csPtr->toRead > csPtr->bufSize)) { + size = csPtr->bufSize; + } else { + size = csPtr->toRead; + } + size = DoRead(csPtr->readPtr, csPtr->buffer, size); + + if (size < 0) { + readError: + errObj = Tcl_NewObj(); + Tcl_AppendStringsToObj(errObj, "error reading \"", + Tcl_GetChannelName(inChan), "\": ", + Tcl_PosixError(interp), (char *) NULL); + break; + } else if (size == 0) { + /* + * We had an underflow on the read side. If we are at EOF, + * then the copying is done, otherwise set up a channel + * handler to detect when the channel becomes readable again. + */ + + if (Tcl_Eof(inChan)) { + break; + } else if (!(mask & TCL_READABLE)) { + if (mask & TCL_WRITABLE) { + Tcl_DeleteChannelHandler(outChan, CopyEventProc, + (ClientData) csPtr); + } + Tcl_CreateChannelHandler(inChan, TCL_READABLE, + CopyEventProc, (ClientData) csPtr); + } + return TCL_OK; + } + + /* + * Now write the buffer out. + */ + + size = DoWrite(csPtr->writePtr, csPtr->buffer, size); + if (size < 0) { + writeError: + errObj = Tcl_NewObj(); + Tcl_AppendStringsToObj(errObj, "error writing \"", + Tcl_GetChannelName(outChan), "\": ", + Tcl_PosixError(interp), (char *) NULL); + break; + } + + /* + * Check to see if the write is happening in the background. If so, + * stop copying and wait for the channel to become writable again. + */ + + if (csPtr->writePtr->flags & BG_FLUSH_SCHEDULED) { + if (!(mask & TCL_WRITABLE)) { + if (mask & TCL_READABLE) { + Tcl_DeleteChannelHandler(outChan, CopyEventProc, + (ClientData) csPtr); + } + Tcl_CreateChannelHandler(outChan, TCL_WRITABLE, + CopyEventProc, (ClientData) csPtr); + } + return TCL_OK; + } + + /* + * Update the current byte count if we care. + */ + + if (csPtr->toRead != -1) { + csPtr->toRead -= size; + } + csPtr->total += size; + + /* + * For background copies, we only do one buffer per invocation so + * we don't starve the rest of the system. + */ + + if (cmdPtr) { + /* + * The first time we enter this code, there won't be a + * channel handler established yet, so do it here. + */ + + if (mask == 0) { + Tcl_CreateChannelHandler(outChan, TCL_WRITABLE, + CopyEventProc, (ClientData) csPtr); + } + return TCL_OK; + } + } + + /* + * Make the callback or return the number of bytes transferred. + * The local total is used because StopCopy frees csPtr. + */ + + total = csPtr->total; + if (cmdPtr) { + /* + * Get a private copy of the command so we can mutate it + * by adding arguments. Note that StopCopy frees our saved + * reference to the original command obj. + */ + + cmdPtr = Tcl_DuplicateObj(cmdPtr); + Tcl_IncrRefCount(cmdPtr); + StopCopy(csPtr); + Tcl_Preserve((ClientData) interp); + + Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewIntObj(total)); + if (errObj) { + Tcl_ListObjAppendElement(interp, cmdPtr, errObj); + } + if (Tcl_EvalObjEx(interp, cmdPtr, TCL_EVAL_GLOBAL) != TCL_OK) { + Tcl_BackgroundError(interp); + result = TCL_ERROR; + } + Tcl_DecrRefCount(cmdPtr); + Tcl_Release((ClientData) interp); + } else { + StopCopy(csPtr); + if (errObj) { + Tcl_SetObjResult(interp, errObj); + result = TCL_ERROR; + } else { + Tcl_ResetResult(interp); + Tcl_SetIntObj(Tcl_GetObjResult(interp), total); + } + } + return result; +} + +/* + *---------------------------------------------------------------------- + * + * DoRead -- + * + * Reads a given number of bytes from a channel. + * + * Results: + * The number of characters read, or -1 on error. Use Tcl_GetErrno() + * to retrieve the error code for the error that occurred. + * + * Side effects: + * May cause input to be buffered. + * + *---------------------------------------------------------------------- + */ + +static int +DoRead(chanPtr, bufPtr, toRead) + Channel *chanPtr; /* The channel from which to read. */ + char *bufPtr; /* Where to store input read. */ + int toRead; /* Maximum number of bytes to read. */ +{ + int copied; /* How many characters were copied into + * the result string? */ + int copiedNow; /* How many characters were copied from + * the current input buffer? */ + int result; /* Of calling GetInput. */ + + /* + * If we have not encountered a sticky EOF, clear the EOF bit. Either + * way clear the BLOCKED bit. We want to discover these anew during + * each operation. + */ + + if (!(chanPtr->flags & CHANNEL_STICKY_EOF)) { + chanPtr->flags &= ~CHANNEL_EOF; + } + chanPtr->flags &= ~(CHANNEL_BLOCKED | CHANNEL_NEED_MORE_DATA); + + for (copied = 0; copied < toRead; copied += copiedNow) { + copiedNow = CopyAndTranslateBuffer(chanPtr, bufPtr + copied, + toRead - copied); + if (copiedNow == 0) { + if (chanPtr->flags & CHANNEL_EOF) { + goto done; + } + if (chanPtr->flags & CHANNEL_BLOCKED) { + if (chanPtr->flags & CHANNEL_NONBLOCKING) { + goto done; + } + chanPtr->flags &= (~(CHANNEL_BLOCKED)); + } + result = GetInput(chanPtr); + if (result != 0) { + if (result != EAGAIN) { + copied = -1; + } + goto done; + } + } + } + + chanPtr->flags &= (~(CHANNEL_BLOCKED)); + + done: + /* + * Update the notifier state so we don't block while there is still + * data in the buffers. + */ + + UpdateInterest(chanPtr); + return copied; +} + +/* + *---------------------------------------------------------------------- + * + * CopyAndTranslateBuffer -- + * + * Copy at most one buffer of input to the result space, doing + * eol translations according to mode in effect currently. + * + * Results: + * Number of bytes stored in the result buffer (as opposed to the + * number of bytes read from the channel). May return + * zero if no input is available to be translated. + * + * Side effects: + * Consumes buffered input. May deallocate one buffer. + * + *---------------------------------------------------------------------- + */ + +static int +CopyAndTranslateBuffer(chanPtr, result, space) + Channel *chanPtr; /* The channel from which to read input. */ + char *result; /* Where to store the copied input. */ + int space; /* How many bytes are available in result + * to store the copied input? */ +{ + int bytesInBuffer; /* How many bytes are available to be + * copied in the current input buffer? */ + int copied; /* How many characters were already copied + * into the destination space? */ + ChannelBuffer *bufPtr; /* The buffer from which to copy bytes. */ + int i; /* Iterates over the copied input looking + * for the input eofChar. */ + + /* + * If there is no input at all, return zero. The invariant is that either + * there is no buffer in the queue, or if the first buffer is empty, it + * is also the last buffer (and thus there is no input in the queue). + * Note also that if the buffer is empty, we leave it in the queue. + */ + + if (chanPtr->inQueueHead == (ChannelBuffer *) NULL) { + return 0; + } + bufPtr = chanPtr->inQueueHead; + bytesInBuffer = bufPtr->nextAdded - bufPtr->nextRemoved; + + copied = 0; + switch (chanPtr->inputTranslation) { + case TCL_TRANSLATE_LF: { + if (bytesInBuffer == 0) { + return 0; + } + + /* + * Copy the current chunk into the result buffer. + */ + + if (bytesInBuffer < space) { + space = bytesInBuffer; + } + memcpy((VOID *) result, + (VOID *) (bufPtr->buf + bufPtr->nextRemoved), + (size_t) space); + bufPtr->nextRemoved += space; + copied = space; + break; + } + case TCL_TRANSLATE_CR: { + char *end; + + if (bytesInBuffer == 0) { + return 0; + } + + /* + * Copy the current chunk into the result buffer, then + * replace all \r with \n. + */ + + if (bytesInBuffer < space) { + space = bytesInBuffer; + } + memcpy((VOID *) result, + (VOID *) (bufPtr->buf + bufPtr->nextRemoved), + (size_t) space); + bufPtr->nextRemoved += space; + copied = space; + + for (end = result + copied; result < end; result++) { + if (*result == '\r') { + *result = '\n'; + } + } + break; + } + case TCL_TRANSLATE_CRLF: { + char *src, *end, *dst; + int curByte; + + /* + * If there is a held-back "\r" at EOF, produce it now. + */ + + if (bytesInBuffer == 0) { + if ((chanPtr->flags & (INPUT_SAW_CR | CHANNEL_EOF)) == + (INPUT_SAW_CR | CHANNEL_EOF)) { + result[0] = '\r'; + chanPtr->flags &= ~INPUT_SAW_CR; + return 1; + } + return 0; + } + + /* + * Copy the current chunk and replace "\r\n" with "\n" + * (but not standalone "\r"!). + */ + + if (bytesInBuffer < space) { + space = bytesInBuffer; + } + memcpy((VOID *) result, + (VOID *) (bufPtr->buf + bufPtr->nextRemoved), + (size_t) space); + bufPtr->nextRemoved += space; + copied = space; + + end = result + copied; + dst = result; + for (src = result; src < end; src++) { + curByte = *src; + if (curByte == '\n') { + chanPtr->flags &= ~INPUT_SAW_CR; + } else if (chanPtr->flags & INPUT_SAW_CR) { + chanPtr->flags &= ~INPUT_SAW_CR; + *dst = '\r'; + dst++; + } + if (curByte == '\r') { + chanPtr->flags |= INPUT_SAW_CR; + } else { + *dst = (char) curByte; + dst++; + } + } + copied = dst - result; + break; + } + case TCL_TRANSLATE_AUTO: { + char *src, *end, *dst; + int curByte; + + if (bytesInBuffer == 0) { + return 0; + } + + /* + * Loop over the current buffer, converting "\r" and "\r\n" + * to "\n". + */ + + if (bytesInBuffer < space) { + space = bytesInBuffer; + } + memcpy((VOID *) result, + (VOID *) (bufPtr->buf + bufPtr->nextRemoved), + (size_t) space); + bufPtr->nextRemoved += space; + copied = space; + + end = result + copied; + dst = result; + for (src = result; src < end; src++) { + curByte = *src; + if (curByte == '\r') { + chanPtr->flags |= INPUT_SAW_CR; + *dst = '\n'; + dst++; + } else { + if ((curByte != '\n') || + !(chanPtr->flags & INPUT_SAW_CR)) { + *dst = (char) curByte; + dst++; + } + chanPtr->flags &= ~INPUT_SAW_CR; + } + } + copied = dst - result; + break; + } + default: { + panic("unknown eol translation mode"); + } + } + + /* + * If an in-stream EOF character is set for this channel, check that + * the input we copied so far does not contain the EOF char. If it does, + * copy only up to and excluding that character. + */ + + if (chanPtr->inEofChar != 0) { + for (i = 0; i < copied; i++) { + if (result[i] == (char) chanPtr->inEofChar) { + /* + * Set sticky EOF so that no further input is presented + * to the caller. + */ + + chanPtr->flags |= (CHANNEL_EOF | CHANNEL_STICKY_EOF); + chanPtr->inputEncodingFlags |= TCL_ENCODING_END; + copied = i; + break; + } + } + } + + /* + * If the current buffer is empty recycle it. + */ + + if (bufPtr->nextRemoved == bufPtr->nextAdded) { + chanPtr->inQueueHead = bufPtr->nextPtr; + if (chanPtr->inQueueHead == (ChannelBuffer *) NULL) { + chanPtr->inQueueTail = (ChannelBuffer *) NULL; + } + RecycleBuffer(chanPtr, bufPtr, 0); + } + + /* + * Return the number of characters copied into the result buffer. + * This may be different from the number of bytes consumed, because + * of EOL translations. + */ + + return copied; +} + +/* + *---------------------------------------------------------------------- + * + * DoWrite -- + * + * Puts a sequence of characters into an output buffer, may queue the + * buffer for output if it gets full, and also remembers whether the + * current buffer is ready e.g. if it contains a newline and we are in + * line buffering mode. + * + * Results: + * The number of bytes written or -1 in case of error. If -1, + * Tcl_GetErrno will return the error code. + * + * Side effects: + * May buffer up output and may cause output to be produced on the + * channel. + * + *---------------------------------------------------------------------- + */ + +static int +DoWrite(chanPtr, src, srcLen) + Channel *chanPtr; /* The channel to buffer output for. */ + char *src; /* Data to write. */ + int srcLen; /* Number of bytes to write. */ +{ + ChannelBuffer *outBufPtr; /* Current output buffer. */ + int foundNewline; /* Did we find a newline in output? */ + char *dPtr; + char *sPtr; /* Search variables for newline. */ + int crsent; /* In CRLF eol translation mode, + * remember the fact that a CR was + * output to the channel without + * its following NL. */ + int i; /* Loop index for newline search. */ + int destCopied; /* How many bytes were used in this + * destination buffer to hold the + * output? */ + int totalDestCopied; /* How many bytes total were + * copied to the channel buffer? */ + int srcCopied; /* How many bytes were copied from + * the source string? */ + char *destPtr; /* Where in line to copy to? */ + + /* + * If we are in network (or windows) translation mode, record the fact + * that we have not yet sent a CR to the channel. + */ + + crsent = 0; + + /* + * Loop filling buffers and flushing them until all output has been + * consumed. + */ + + srcCopied = 0; + totalDestCopied = 0; + + while (srcLen > 0) { + + /* + * Make sure there is a current output buffer to accept output. + */ + + if (chanPtr->curOutPtr == (ChannelBuffer *) NULL) { + chanPtr->curOutPtr = AllocChannelBuffer(chanPtr->bufSize); + } + + outBufPtr = chanPtr->curOutPtr; + + destCopied = outBufPtr->bufLength - outBufPtr->nextAdded; + if (destCopied > srcLen) { + destCopied = srcLen; + } + + destPtr = outBufPtr->buf + outBufPtr->nextAdded; + switch (chanPtr->outputTranslation) { + case TCL_TRANSLATE_LF: + srcCopied = destCopied; + memcpy((VOID *) destPtr, (VOID *) src, (size_t) destCopied); + break; + case TCL_TRANSLATE_CR: + srcCopied = destCopied; + memcpy((VOID *) destPtr, (VOID *) src, (size_t) destCopied); + for (dPtr = destPtr; dPtr < destPtr + destCopied; dPtr++) { + if (*dPtr == '\n') { + *dPtr = '\r'; + } + } + break; + case TCL_TRANSLATE_CRLF: + for (srcCopied = 0, dPtr = destPtr, sPtr = src; + dPtr < destPtr + destCopied; + dPtr++, sPtr++, srcCopied++) { + if (*sPtr == '\n') { + if (crsent) { + *dPtr = '\n'; + crsent = 0; + } else { + *dPtr = '\r'; + crsent = 1; + sPtr--, srcCopied--; + } + } else { + *dPtr = *sPtr; + } + } + break; + case TCL_TRANSLATE_AUTO: + panic("Tcl_Write: AUTO output translation mode not supported"); + default: + panic("Tcl_Write: unknown output translation mode"); + } + + /* + * The current buffer is ready for output if it is full, or if it + * contains a newline and this channel is line-buffered, or if it + * contains any output and this channel is unbuffered. + */ + + outBufPtr->nextAdded += destCopied; + if (!(chanPtr->flags & BUFFER_READY)) { + if (outBufPtr->nextAdded == outBufPtr->bufLength) { + chanPtr->flags |= BUFFER_READY; + } else if (chanPtr->flags & CHANNEL_LINEBUFFERED) { + for (sPtr = src, i = 0, foundNewline = 0; + (i < srcCopied) && (!foundNewline); + i++, sPtr++) { + if (*sPtr == '\n') { + foundNewline = 1; + break; + } + } + if (foundNewline) { + chanPtr->flags |= BUFFER_READY; + } + } else if (chanPtr->flags & CHANNEL_UNBUFFERED) { + chanPtr->flags |= BUFFER_READY; + } + } + + totalDestCopied += srcCopied; + src += srcCopied; + srcLen -= srcCopied; + + if (chanPtr->flags & BUFFER_READY) { + if (FlushChannel(NULL, chanPtr, 0) != 0) { + return -1; + } + } + } /* Closes "while" */ + + return totalDestCopied; +} + +/* + *---------------------------------------------------------------------- + * + * CopyEventProc -- + * + * This routine is invoked as a channel event handler for + * the background copy operation. It is just a trivial wrapper + * around the CopyData routine. + * + * Results: + * None. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static void +CopyEventProc(clientData, mask) + ClientData clientData; + int mask; +{ + (void) CopyData((CopyState *)clientData, mask); +} + +/* + *---------------------------------------------------------------------- + * + * StopCopy -- + * + * This routine halts a copy that is in progress. + * + * Results: + * None. + * + * Side effects: + * Removes any pending channel handlers and restores the blocking + * and buffering modes of the channels. The CopyState is freed. + * + *---------------------------------------------------------------------- + */ + +static void +StopCopy(csPtr) + CopyState *csPtr; /* State for bg copy to stop . */ +{ + int nonBlocking; + + if (!csPtr) { + return; + } + + /* + * Restore the old blocking mode and output buffering mode. + */ + + nonBlocking = (csPtr->readFlags & CHANNEL_NONBLOCKING); + if (nonBlocking != (csPtr->readPtr->flags & CHANNEL_NONBLOCKING)) { + SetBlockMode(NULL, csPtr->readPtr, + nonBlocking ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING); + } + if (csPtr->writePtr != csPtr->writePtr) { + if (nonBlocking != (csPtr->writePtr->flags & CHANNEL_NONBLOCKING)) { + SetBlockMode(NULL, csPtr->writePtr, + nonBlocking ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING); + } + } + csPtr->writePtr->flags &= ~(CHANNEL_LINEBUFFERED | CHANNEL_UNBUFFERED); + csPtr->writePtr->flags |= + csPtr->writeFlags & (CHANNEL_LINEBUFFERED | CHANNEL_UNBUFFERED); + + + if (csPtr->cmdPtr) { + Tcl_DeleteChannelHandler((Tcl_Channel)csPtr->readPtr, CopyEventProc, + (ClientData)csPtr); + if (csPtr->readPtr != csPtr->writePtr) { + Tcl_DeleteChannelHandler((Tcl_Channel)csPtr->writePtr, + CopyEventProc, (ClientData)csPtr); + } + Tcl_DecrRefCount(csPtr->cmdPtr); + } + csPtr->readPtr->csPtr = NULL; + csPtr->writePtr->csPtr = NULL; + ckfree((char*) csPtr); +} + +/* + *---------------------------------------------------------------------- + * + * SetBlockMode -- + * + * This function sets the blocking mode for a channel and updates + * the state flags. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * Modifies the blocking mode of the channel and possibly generates + * an error. + * + *---------------------------------------------------------------------- + */ + +static int +SetBlockMode(interp, chanPtr, mode) + Tcl_Interp *interp; /* Interp for error reporting. */ + Channel *chanPtr; /* Channel to modify. */ + int mode; /* One of TCL_MODE_BLOCKING or + * TCL_MODE_NONBLOCKING. */ +{ + int result = 0; + if (chanPtr->typePtr->blockModeProc != NULL) { + result = (chanPtr->typePtr->blockModeProc) (chanPtr->instanceData, + mode); + } + if (result != 0) { + Tcl_SetErrno(result); + if (interp != (Tcl_Interp *) NULL) { + Tcl_AppendResult(interp, "error setting blocking mode: ", + Tcl_PosixError(interp), (char *) NULL); + } + return TCL_ERROR; + } + if (mode == TCL_MODE_BLOCKING) { + chanPtr->flags &= (~(CHANNEL_NONBLOCKING | BG_FLUSH_SCHEDULED)); + } else { + chanPtr->flags |= CHANNEL_NONBLOCKING; + } + return TCL_OK; +} |