diff options
Diffstat (limited to 'win/tclWinConsole.c')
| -rw-r--r-- | win/tclWinConsole.c | 1502 |
1 files changed, 1502 insertions, 0 deletions
diff --git a/win/tclWinConsole.c b/win/tclWinConsole.c new file mode 100644 index 0000000..5ce8a2b --- /dev/null +++ b/win/tclWinConsole.c @@ -0,0 +1,1502 @@ +/* + * tclWinConsole.c -- + * + * This file implements the Windows-specific console functions, and the + * "console" channel driver. + * + * Copyright (c) 1999 by Scriptics Corp. + * + * See the file "license.terms" for information on usage and redistribution of + * this file, and for a DISCLAIMER OF ALL WARRANTIES. + */ + +#include "tclWinInt.h" + +/* + * The following variable is used to tell whether this module has been + * initialized. + */ + +static int initialized = 0; + +/* + * The consoleMutex locks around access to the initialized variable, and it is + * used to protect background threads from being terminated while they are + * using APIs that hold locks. + */ + +TCL_DECLARE_MUTEX(consoleMutex) + +/* + * Bit masks used in the flags field of the ConsoleInfo structure below. + */ + +#define CONSOLE_PENDING (1<<0) /* Message is pending in the queue. */ +#define CONSOLE_ASYNC (1<<1) /* Channel is non-blocking. */ + +/* + * Bit masks used in the sharedFlags field of the ConsoleInfo structure below. + */ + +#define CONSOLE_EOF (1<<2) /* Console has reached EOF. */ +#define CONSOLE_BUFFERED (1<<3) /* Data was read into a buffer by the reader + * thread. */ + +#define CONSOLE_BUFFER_SIZE (8*1024) + +/* + * Structure containing handles associated with one of the special console + * threads. + */ + +typedef struct { + HANDLE thread; /* Handle to reader or writer thread. */ + HANDLE readyEvent; /* Manual-reset event to signal _to_ the main + * thread when the worker thread has finished + * waiting for its normal work to happen. */ + HANDLE startEvent; /* Auto-reset event used by the main thread to + * signal when the thread should attempt to do + * its normal work. */ + HANDLE stopEvent; /* Auto-reset event used by the main thread to + * signal when the thread should exit. */ +} ConsoleThreadInfo; + +/* + * This structure describes per-instance data for a console based channel. + */ + +typedef struct ConsoleInfo { + HANDLE handle; + int type; + struct ConsoleInfo *nextPtr;/* Pointer to next registered console. */ + Tcl_Channel channel; /* Pointer to channel structure. */ + int validMask; /* OR'ed combination of TCL_READABLE, + * TCL_WRITABLE, or TCL_EXCEPTION: indicates + * which operations are valid on the file. */ + int watchMask; /* OR'ed combination of TCL_READABLE, + * TCL_WRITABLE, or TCL_EXCEPTION: indicates + * which events should be reported. */ + int flags; /* State flags, see above for a list. */ + Tcl_ThreadId threadId; /* Thread to which events should be reported. + * This value is used by the reader/writer + * threads. */ + ConsoleThreadInfo writer; /* A specialized thread for handling + * asynchronous writes to the console; the + * waiting starts when a start event is sent, + * and a reset event is sent back to the main + * thread when the write is done. A stop event + * is used to terminate the thread. */ + ConsoleThreadInfo reader; /* A specialized thread for handling + * asynchronous reads from the console; the + * waiting starts when a start event is sent, + * and a reset event is sent back to the main + * thread when input is available. A stop + * event is used to terminate the thread. */ + DWORD writeError; /* An error caused by the last background + * write. Set to 0 if no error has been + * detected. This word is shared with the + * writer thread so access must be + * synchronized with the writable object. */ + char *writeBuf; /* Current background output buffer. Access is + * synchronized with the writable object. */ + int writeBufLen; /* Size of write buffer. Access is + * synchronized with the writable object. */ + int toWrite; /* Current amount to be written. Access is + * synchronized with the writable object. */ + int readFlags; /* Flags that are shared with the reader + * thread. Access is synchronized with the + * readable object. */ + int bytesRead; /* Number of bytes in the buffer. */ + int offset; /* Number of bytes read out of the buffer. */ + char buffer[CONSOLE_BUFFER_SIZE]; + /* Data consumed by reader thread. */ +} ConsoleInfo; + +typedef struct { + /* + * The following pointer refers to the head of the list of consoles that + * are being watched for file events. + */ + + ConsoleInfo *firstConsolePtr; +} ThreadSpecificData; + +static Tcl_ThreadDataKey dataKey; + +/* + * The following structure is what is added to the Tcl event queue when + * console events are generated. + */ + +typedef struct { + Tcl_Event header; /* Information that is standard for all + * events. */ + ConsoleInfo *infoPtr; /* Pointer to console info structure. Note + * that we still have to verify that the + * console exists before dereferencing this + * pointer. */ +} ConsoleEvent; + +/* + * Declarations for functions used only in this file. + */ + +static int ConsoleBlockModeProc(ClientData instanceData, + int mode); +static void ConsoleCheckProc(ClientData clientData, int flags); +static int ConsoleCloseProc(ClientData instanceData, + Tcl_Interp *interp); +static int ConsoleEventProc(Tcl_Event *evPtr, int flags); +static void ConsoleExitHandler(ClientData clientData); +static int ConsoleGetHandleProc(ClientData instanceData, + int direction, ClientData *handlePtr); +static void ConsoleInit(void); +static int ConsoleInputProc(ClientData instanceData, char *buf, + int toRead, int *errorCode); +static int ConsoleOutputProc(ClientData instanceData, + const char *buf, int toWrite, int *errorCode); +static DWORD WINAPI ConsoleReaderThread(LPVOID arg); +static void ConsoleSetupProc(ClientData clientData, int flags); +static void ConsoleWatchProc(ClientData instanceData, int mask); +static DWORD WINAPI ConsoleWriterThread(LPVOID arg); +static void ProcExitHandler(ClientData clientData); +static int WaitForRead(ConsoleInfo *infoPtr, int blocking); +static void ConsoleThreadActionProc(ClientData instanceData, + int action); +static BOOL ReadConsoleBytes(HANDLE hConsole, LPVOID lpBuffer, + DWORD nbytes, LPDWORD nbytesread); +static BOOL WriteConsoleBytes(HANDLE hConsole, + const void *lpBuffer, DWORD nbytes, + LPDWORD nbyteswritten); +static void StartChannelThread(ConsoleInfo *infoPtr, + ConsoleThreadInfo *threadInfoPtr, + LPTHREAD_START_ROUTINE threadProc); +static void StopChannelThread(ConsoleThreadInfo *threadInfoPtr); + +/* + * This structure describes the channel type structure for command console + * based IO. + */ + +static const Tcl_ChannelType consoleChannelType = { + "console", /* Type name. */ + TCL_CHANNEL_VERSION_5, /* v5 channel */ + ConsoleCloseProc, /* Close proc. */ + ConsoleInputProc, /* Input proc. */ + ConsoleOutputProc, /* Output proc. */ + NULL, /* Seek proc. */ + NULL, /* Set option proc. */ + NULL, /* Get option proc. */ + ConsoleWatchProc, /* Set up notifier to watch the channel. */ + ConsoleGetHandleProc, /* Get an OS handle from channel. */ + NULL, /* close2proc. */ + ConsoleBlockModeProc, /* Set blocking or non-blocking mode. */ + NULL, /* Flush proc. */ + NULL, /* Handler proc. */ + NULL, /* Wide seek proc. */ + ConsoleThreadActionProc, /* Thread action proc. */ + NULL /* Truncation proc. */ +}; + +/* + *---------------------------------------------------------------------- + * + * ReadConsoleBytes, WriteConsoleBytes -- + * + * Wrapper for ReadConsole{A,W}, that takes and returns number of bytes + * instead of number of TCHARS. + * + *---------------------------------------------------------------------- + */ + +static BOOL +ReadConsoleBytes( + HANDLE hConsole, + LPVOID lpBuffer, + DWORD nbytes, + LPDWORD nbytesread) +{ + DWORD ntchars; + BOOL result; + int tcharsize = sizeof(TCHAR); + + /* + * If user types a Ctrl-Break or Ctrl-C, ReadConsole will return + * success with ntchars == 0 and GetLastError() will be + * ERROR_OPERATION_ABORTED. We do not want to treat this case + * as EOF so we will loop around again. If no Ctrl signal handlers + * have been established, the default signal OS handler in a separate + * thread will terminate the program. If a Ctrl signal handler + * has been established (through an extension for example), it + * will run and take whatever action it deems appropriate. + */ + do { + result = ReadConsole(hConsole, lpBuffer, nbytes / tcharsize, &ntchars, + NULL); + } while (result && ntchars == 0 && GetLastError() == ERROR_OPERATION_ABORTED); + if (nbytesread != NULL) { + *nbytesread = ntchars * tcharsize; + } + return result; +} + +static BOOL +WriteConsoleBytes( + HANDLE hConsole, + const void *lpBuffer, + DWORD nbytes, + LPDWORD nbyteswritten) +{ + DWORD ntchars; + BOOL result; + int tcharsize = sizeof(TCHAR); + + result = WriteConsole(hConsole, lpBuffer, nbytes / tcharsize, &ntchars, + NULL); + if (nbyteswritten != NULL) { + *nbyteswritten = ntchars * tcharsize; + } + return result; +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleInit -- + * + * This function initializes the static variables for this file. + * + * Results: + * None. + * + * Side effects: + * Creates a new event source. + * + *---------------------------------------------------------------------- + */ + +static void +ConsoleInit(void) +{ + /* + * Check the initialized flag first, then check again in the mutex. This + * is a speed enhancement. + */ + + if (!initialized) { + Tcl_MutexLock(&consoleMutex); + if (!initialized) { + initialized = 1; + Tcl_CreateExitHandler(ProcExitHandler, NULL); + } + Tcl_MutexUnlock(&consoleMutex); + } + + if (TclThreadDataKeyGet(&dataKey) == NULL) { + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + tsdPtr->firstConsolePtr = NULL; + Tcl_CreateEventSource(ConsoleSetupProc, ConsoleCheckProc, NULL); + Tcl_CreateThreadExitHandler(ConsoleExitHandler, NULL); + } +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleExitHandler -- + * + * This function is called to cleanup the console module before Tcl is + * unloaded. + * + * Results: + * None. + * + * Side effects: + * Removes the console event source. + * + *---------------------------------------------------------------------- + */ + +static void +ConsoleExitHandler( + ClientData clientData) /* Old window proc. */ +{ + Tcl_DeleteEventSource(ConsoleSetupProc, ConsoleCheckProc, NULL); +} + +/* + *---------------------------------------------------------------------- + * + * ProcExitHandler -- + * + * This function is called to cleanup the process list before Tcl is + * unloaded. + * + * Results: + * None. + * + * Side effects: + * Resets the process list. + * + *---------------------------------------------------------------------- + */ + +static void +ProcExitHandler( + ClientData clientData) /* Old window proc. */ +{ + Tcl_MutexLock(&consoleMutex); + initialized = 0; + Tcl_MutexUnlock(&consoleMutex); +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleSetupProc -- + * + * This procedure is invoked before Tcl_DoOneEvent blocks waiting for an + * event. + * + * Results: + * None. + * + * Side effects: + * Adjusts the block time if needed. + * + *---------------------------------------------------------------------- + */ + +void +ConsoleSetupProc( + ClientData data, /* Not used. */ + int flags) /* Event flags as passed to Tcl_DoOneEvent. */ +{ + ConsoleInfo *infoPtr; + Tcl_Time blockTime = { 0, 0 }; + int block = 1; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + if (!(flags & TCL_FILE_EVENTS)) { + return; + } + + /* + * Look to see if any events are already pending. If they are, poll. + */ + + for (infoPtr = tsdPtr->firstConsolePtr; infoPtr != NULL; + infoPtr = infoPtr->nextPtr) { + if (infoPtr->watchMask & TCL_WRITABLE) { + if (WaitForSingleObject(infoPtr->writer.readyEvent, + 0) != WAIT_TIMEOUT) { + block = 0; + } + } + if (infoPtr->watchMask & TCL_READABLE) { + if (WaitForRead(infoPtr, 0) >= 0) { + block = 0; + } + } + } + if (!block) { + Tcl_SetMaxBlockTime(&blockTime); + } +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleCheckProc -- + * + * This procedure is called by Tcl_DoOneEvent to check the console event + * source for events. + * + * Results: + * None. + * + * Side effects: + * May queue an event. + * + *---------------------------------------------------------------------- + */ + +static void +ConsoleCheckProc( + ClientData data, /* Not used. */ + int flags) /* Event flags as passed to Tcl_DoOneEvent. */ +{ + ConsoleInfo *infoPtr; + int needEvent; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + if (!(flags & TCL_FILE_EVENTS)) { + return; + } + + /* + * Queue events for any ready consoles that don't already have events + * queued. + */ + + for (infoPtr = tsdPtr->firstConsolePtr; infoPtr != NULL; + infoPtr = infoPtr->nextPtr) { + if (infoPtr->flags & CONSOLE_PENDING) { + continue; + } + + /* + * Queue an event if the console is signaled for reading or writing. + */ + + needEvent = 0; + if (infoPtr->watchMask & TCL_WRITABLE) { + if (WaitForSingleObject(infoPtr->writer.readyEvent, + 0) != WAIT_TIMEOUT) { + needEvent = 1; + } + } + + if (infoPtr->watchMask & TCL_READABLE) { + if (WaitForRead(infoPtr, 0) >= 0) { + needEvent = 1; + } + } + + if (needEvent) { + ConsoleEvent *evPtr = ckalloc(sizeof(ConsoleEvent)); + + infoPtr->flags |= CONSOLE_PENDING; + evPtr->header.proc = ConsoleEventProc; + evPtr->infoPtr = infoPtr; + Tcl_QueueEvent((Tcl_Event *) evPtr, TCL_QUEUE_TAIL); + } + } +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleBlockModeProc -- + * + * Set blocking or non-blocking mode on channel. + * + * Results: + * 0 if successful, errno when failed. + * + * Side effects: + * Sets the device into blocking or non-blocking mode. + * + *---------------------------------------------------------------------- + */ + +static int +ConsoleBlockModeProc( + ClientData instanceData, /* Instance data for channel. */ + int mode) /* TCL_MODE_BLOCKING or + * TCL_MODE_NONBLOCKING. */ +{ + ConsoleInfo *infoPtr = instanceData; + + /* + * Consoles on Windows can not be switched between blocking and + * nonblocking, hence we have to emulate the behavior. This is done in the + * input function by checking against a bit in the state. We set or unset + * the bit here to cause the input function to emulate the correct + * behavior. + */ + + if (mode == TCL_MODE_NONBLOCKING) { + infoPtr->flags |= CONSOLE_ASYNC; + } else { + infoPtr->flags &= ~CONSOLE_ASYNC; + } + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * StartChannelThread, StopChannelThread -- + * + * Helpers that codify how to ask one of the console service threads to + * start and stop. + * + *---------------------------------------------------------------------- + */ + +static void +StartChannelThread( + ConsoleInfo *infoPtr, + ConsoleThreadInfo *threadInfoPtr, + LPTHREAD_START_ROUTINE threadProc) +{ + DWORD id; + + threadInfoPtr->readyEvent = CreateEvent(NULL, TRUE, TRUE, NULL); + threadInfoPtr->startEvent = CreateEvent(NULL, FALSE, FALSE, NULL); + threadInfoPtr->stopEvent = CreateEvent(NULL, FALSE, FALSE, NULL); + threadInfoPtr->thread = CreateThread(NULL, 256, threadProc, infoPtr, 0, + &id); + SetThreadPriority(threadInfoPtr->thread, THREAD_PRIORITY_HIGHEST); +} + +static void +StopChannelThread( + ConsoleThreadInfo *threadInfoPtr) +{ + DWORD exitCode = 0; + + /* + * The thread may already have closed on it's own. Check it's exit + * code. + */ + + GetExitCodeThread(threadInfoPtr->thread, &exitCode); + if (exitCode == STILL_ACTIVE) { + /* + * Set the stop event so that if the reader thread is blocked in + * ConsoleReaderThread on WaitForMultipleEvents, it will exit cleanly. + */ + + SetEvent(threadInfoPtr->stopEvent); + + /* + * Wait at most 20 milliseconds for the reader thread to close. + */ + + if (WaitForSingleObject(threadInfoPtr->thread, 20) == WAIT_TIMEOUT) { + /* + * Forcibly terminate the background thread as a last resort. + * Note that we need to guard against terminating the thread while + * it is in the middle of Tcl_ThreadAlert because it won't be able + * to release the notifier lock. + */ + + Tcl_MutexLock(&consoleMutex); + /* BUG: this leaks memory. */ + TerminateThread(threadInfoPtr->thread, 0); + Tcl_MutexUnlock(&consoleMutex); + } + } + + /* + * Close all the handles associated with the thread, and set the thread + * handle field to NULL to mark that the thread has been cleaned up. + */ + + CloseHandle(threadInfoPtr->thread); + CloseHandle(threadInfoPtr->readyEvent); + CloseHandle(threadInfoPtr->startEvent); + CloseHandle(threadInfoPtr->stopEvent); + threadInfoPtr->thread = NULL; +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleCloseProc -- + * + * Closes a console based IO channel. + * + * Results: + * 0 on success, errno otherwise. + * + * Side effects: + * Closes the physical channel. + * + *---------------------------------------------------------------------- + */ + +static int +ConsoleCloseProc( + ClientData instanceData, /* Pointer to ConsoleInfo structure. */ + Tcl_Interp *interp) /* For error reporting. */ +{ + ConsoleInfo *consolePtr = instanceData; + int errorCode = 0; + ConsoleInfo *infoPtr, **nextPtrPtr; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + /* + * Clean up the background thread if necessary. Note that this must be + * done before we can close the file, since the thread may be blocking + * trying to read from the console. + */ + + if (consolePtr->reader.thread) { + StopChannelThread(&consolePtr->reader); + } + consolePtr->validMask &= ~TCL_READABLE; + + /* + * Wait for the writer thread to finish the current buffer, then terminate + * the thread and close the handles. If the channel is nonblocking, there + * should be no pending write operations. + */ + + if (consolePtr->writer.thread) { + if (consolePtr->toWrite) { + /* + * We only need to wait if there is something to write. This may + * prevent infinite wait on exit. [Python Bug 216289] + */ + + WaitForSingleObject(consolePtr->writer.readyEvent, INFINITE); + } + + StopChannelThread(&consolePtr->writer); + } + consolePtr->validMask &= ~TCL_WRITABLE; + + /* + * Don't close the Win32 handle if the handle is a standard channel during + * the thread exit process. Otherwise, one thread may kill the stdio of + * another. + */ + + if (!TclInThreadExit() + || ((GetStdHandle(STD_INPUT_HANDLE) != consolePtr->handle) + && (GetStdHandle(STD_OUTPUT_HANDLE) != consolePtr->handle) + && (GetStdHandle(STD_ERROR_HANDLE) != consolePtr->handle))) { + if (CloseHandle(consolePtr->handle) == FALSE) { + TclWinConvertError(GetLastError()); + errorCode = errno; + } + } + + consolePtr->watchMask &= consolePtr->validMask; + + /* + * Remove the file from the list of watched files. + */ + + for (nextPtrPtr = &(tsdPtr->firstConsolePtr), infoPtr = *nextPtrPtr; + infoPtr != NULL; + nextPtrPtr = &infoPtr->nextPtr, infoPtr = *nextPtrPtr) { + if (infoPtr == (ConsoleInfo *) consolePtr) { + *nextPtrPtr = infoPtr->nextPtr; + break; + } + } + if (consolePtr->writeBuf != NULL) { + ckfree(consolePtr->writeBuf); + consolePtr->writeBuf = 0; + } + ckfree(consolePtr); + + return errorCode; +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleInputProc -- + * + * Reads input from the IO channel into the buffer given. Returns count + * of how many bytes were actually read, and an error indication. + * + * Results: + * A count of how many bytes were read is returned and an error + * indication is returned in an output argument. + * + * Side effects: + * Reads input from the actual channel. + * + *---------------------------------------------------------------------- + */ + +static int +ConsoleInputProc( + ClientData instanceData, /* Console state. */ + char *buf, /* Where to store data read. */ + int bufSize, /* How much space is available in the + * buffer? */ + int *errorCode) /* Where to store error code. */ +{ + ConsoleInfo *infoPtr = instanceData; + DWORD count, bytesRead = 0; + int result; + + *errorCode = 0; + + /* + * Synchronize with the reader thread. + */ + + result = WaitForRead(infoPtr, (infoPtr->flags & CONSOLE_ASYNC) ? 0 : 1); + + /* + * If an error occurred, return immediately. + */ + + if (result == -1) { + *errorCode = errno; + return -1; + } + + if (infoPtr->readFlags & CONSOLE_BUFFERED) { + /* + * Data is stored in the buffer. + */ + + if (bufSize < (infoPtr->bytesRead - infoPtr->offset)) { + memcpy(buf, &infoPtr->buffer[infoPtr->offset], (size_t) bufSize); + bytesRead = bufSize; + infoPtr->offset += bufSize; + } else { + memcpy(buf, &infoPtr->buffer[infoPtr->offset], (size_t) bufSize); + bytesRead = infoPtr->bytesRead - infoPtr->offset; + + /* + * Reset the buffer. + */ + + infoPtr->readFlags &= ~CONSOLE_BUFFERED; + infoPtr->offset = 0; + } + + return bytesRead; + } + + /* + * Attempt to read bufSize bytes. The read will return immediately if + * there is any data available. Otherwise it will block until at least one + * byte is available or an EOF occurs. + */ + + if (ReadConsoleBytes(infoPtr->handle, (LPVOID) buf, (DWORD) bufSize, + &count) == TRUE) { + /* + * TODO: This potentially writes beyond the limits specified + * by the caller. In practice this is harmless, since all writes + * are into ChannelBuffers, and those have padding, but still + * ought to remove this, unless some Windows wizard can give + * a reason not to. + */ + buf[count] = '\0'; + return count; + } + + return -1; +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleOutputProc -- + * + * Writes the given output on the IO channel. Returns count of how many + * characters were actually written, and an error indication. + * + * Results: + * A count of how many characters were written is returned and an error + * indication is returned in an output argument. + * + * Side effects: + * Writes output on the actual channel. + * + *---------------------------------------------------------------------- + */ + +static int +ConsoleOutputProc( + ClientData instanceData, /* Console state. */ + const char *buf, /* The data buffer. */ + int toWrite, /* How many bytes to write? */ + int *errorCode) /* Where to store error code. */ +{ + ConsoleInfo *infoPtr = instanceData; + ConsoleThreadInfo *threadInfo = &infoPtr->reader; + DWORD bytesWritten, timeout; + + *errorCode = 0; + timeout = (infoPtr->flags & CONSOLE_ASYNC) ? 0 : INFINITE; + if (WaitForSingleObject(threadInfo->readyEvent,timeout) == WAIT_TIMEOUT) { + /* + * The writer thread is blocked waiting for a write to complete and + * the channel is in non-blocking mode. + */ + + errno = EWOULDBLOCK; + goto error; + } + + /* + * Check for a background error on the last write. + */ + + if (infoPtr->writeError) { + TclWinConvertError(infoPtr->writeError); + infoPtr->writeError = 0; + goto error; + } + + if (infoPtr->flags & CONSOLE_ASYNC) { + /* + * The console is non-blocking, so copy the data into the output + * buffer and restart the writer thread. + */ + + if (toWrite > infoPtr->writeBufLen) { + /* + * Reallocate the buffer to be large enough to hold the data. + */ + + if (infoPtr->writeBuf) { + ckfree(infoPtr->writeBuf); + } + infoPtr->writeBufLen = toWrite; + infoPtr->writeBuf = ckalloc(toWrite); + } + memcpy(infoPtr->writeBuf, buf, (size_t) toWrite); + infoPtr->toWrite = toWrite; + ResetEvent(threadInfo->readyEvent); + SetEvent(threadInfo->startEvent); + bytesWritten = toWrite; + } else { + /* + * In the blocking case, just try to write the buffer directly. This + * avoids an unnecessary copy. + */ + + if (WriteConsoleBytes(infoPtr->handle, buf, (DWORD) toWrite, + &bytesWritten) == FALSE) { + TclWinConvertError(GetLastError()); + goto error; + } + } + return bytesWritten; + + error: + *errorCode = errno; + return -1; +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleEventProc -- + * + * This function is invoked by Tcl_ServiceEvent when a file event reaches + * the front of the event queue. This procedure invokes Tcl_NotifyChannel + * on the console. + * + * Results: + * Returns 1 if the event was handled, meaning it should be removed from + * the queue. Returns 0 if the event was not handled, meaning it should + * stay on the queue. The only time the event isn't handled is if the + * TCL_FILE_EVENTS flag bit isn't set. + * + * Side effects: + * Whatever the notifier callback does. + * + *---------------------------------------------------------------------- + */ + +static int +ConsoleEventProc( + Tcl_Event *evPtr, /* Event to service. */ + int flags) /* Flags that indicate what events to handle, + * such as TCL_FILE_EVENTS. */ +{ + ConsoleEvent *consoleEvPtr = (ConsoleEvent *) evPtr; + ConsoleInfo *infoPtr; + int mask; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + if (!(flags & TCL_FILE_EVENTS)) { + return 0; + } + + /* + * Search through the list of watched consoles for the one whose handle + * matches the event. We do this rather than simply dereferencing the + * handle in the event so that consoles can be deleted while the event is + * in the queue. + */ + + for (infoPtr = tsdPtr->firstConsolePtr; infoPtr != NULL; + infoPtr = infoPtr->nextPtr) { + if (consoleEvPtr->infoPtr == infoPtr) { + infoPtr->flags &= ~CONSOLE_PENDING; + break; + } + } + + /* + * Remove stale events. + */ + + if (!infoPtr) { + return 1; + } + + /* + * Check to see if the console is readable. Note that we can't tell if a + * console is writable, so we always report it as being writable unless we + * have detected EOF. + */ + + mask = 0; + if (infoPtr->watchMask & TCL_WRITABLE) { + if (WaitForSingleObject(infoPtr->writer.readyEvent, + 0) != WAIT_TIMEOUT) { + mask = TCL_WRITABLE; + } + } + + if (infoPtr->watchMask & TCL_READABLE) { + if (WaitForRead(infoPtr, 0) >= 0) { + if (infoPtr->readFlags & CONSOLE_EOF) { + mask = TCL_READABLE; + } else { + mask |= TCL_READABLE; + } + } + } + + /* + * Inform the channel of the events. + */ + + Tcl_NotifyChannel(infoPtr->channel, infoPtr->watchMask & mask); + return 1; +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleWatchProc -- + * + * Called by the notifier to set up to watch for events on this channel. + * + * Results: + * None. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static void +ConsoleWatchProc( + ClientData instanceData, /* Console state. */ + int mask) /* What events to watch for, OR-ed combination + * of TCL_READABLE, TCL_WRITABLE and + * TCL_EXCEPTION. */ +{ + ConsoleInfo **nextPtrPtr, *ptr; + ConsoleInfo *infoPtr = instanceData; + int oldMask = infoPtr->watchMask; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + /* + * Since most of the work is handled by the background threads, we just + * need to update the watchMask and then force the notifier to poll once. + */ + + infoPtr->watchMask = mask & infoPtr->validMask; + if (infoPtr->watchMask) { + Tcl_Time blockTime = { 0, 0 }; + + if (!oldMask) { + infoPtr->nextPtr = tsdPtr->firstConsolePtr; + tsdPtr->firstConsolePtr = infoPtr; + } + Tcl_SetMaxBlockTime(&blockTime); + } else if (oldMask) { + /* + * Remove the console from the list of watched consoles. + */ + + for (nextPtrPtr = &(tsdPtr->firstConsolePtr), ptr = *nextPtrPtr; + ptr != NULL; + nextPtrPtr = &ptr->nextPtr, ptr = *nextPtrPtr) { + if (infoPtr == ptr) { + *nextPtrPtr = ptr->nextPtr; + break; + } + } + } +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleGetHandleProc -- + * + * Called from Tcl_GetChannelHandle to retrieve OS handles from inside a + * command consoleline based channel. + * + * Results: + * Returns TCL_OK with the fd in handlePtr, or TCL_ERROR if there is no + * handle for the specified direction. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static int +ConsoleGetHandleProc( + ClientData instanceData, /* The console state. */ + int direction, /* TCL_READABLE or TCL_WRITABLE. */ + ClientData *handlePtr) /* Where to store the handle. */ +{ + ConsoleInfo *infoPtr = instanceData; + + *handlePtr = infoPtr->handle; + return TCL_OK; +} + +/* + *---------------------------------------------------------------------- + * + * WaitForRead -- + * + * Wait until some data is available, the console is at EOF or the reader + * thread is blocked waiting for data (if the channel is in non-blocking + * mode). + * + * Results: + * Returns 1 if console is readable. Returns 0 if there is no data on the + * console, but there is buffered data. Returns -1 if an error occurred. + * If an error occurred, the threads may not be synchronized. + * + * Side effects: + * Updates the shared state flags. If no error occurred, the reader + * thread is blocked waiting for a signal from the main thread. + * + *---------------------------------------------------------------------- + */ + +static int +WaitForRead( + ConsoleInfo *infoPtr, /* Console state. */ + int blocking) /* Indicates whether call should be blocking + * or not. */ +{ + DWORD timeout, count; + HANDLE *handle = infoPtr->handle; + ConsoleThreadInfo *threadInfo = &infoPtr->reader; + INPUT_RECORD input; + + while (1) { + /* + * Synchronize with the reader thread. + */ + + timeout = blocking ? INFINITE : 0; + if (WaitForSingleObject(threadInfo->readyEvent, + timeout) == WAIT_TIMEOUT) { + /* + * The reader thread is blocked waiting for data and the channel + * is in non-blocking mode. + */ + + errno = EWOULDBLOCK; + return -1; + } + + /* + * At this point, the two threads are synchronized, so it is safe to + * access shared state. + */ + + /* + * If the console has hit EOF, it is always readable. + */ + + if (infoPtr->readFlags & CONSOLE_EOF) { + return 1; + } + + if (PeekConsoleInput(handle, &input, 1, &count) == FALSE) { + /* + * Check to see if the peek failed because of EOF. + */ + + TclWinConvertError(GetLastError()); + + if (errno == EOF) { + infoPtr->readFlags |= CONSOLE_EOF; + return 1; + } + + /* + * Ignore errors if there is data in the buffer. + */ + + if (infoPtr->readFlags & CONSOLE_BUFFERED) { + return 0; + } else { + return -1; + } + } + + /* + * If there is data in the buffer, the console must be readable (since + * it is a line-oriented device). + */ + + if (infoPtr->readFlags & CONSOLE_BUFFERED) { + return 1; + } + + /* + * There wasn't any data available, so reset the thread and try again. + */ + + ResetEvent(threadInfo->readyEvent); + SetEvent(threadInfo->startEvent); + } +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleReaderThread -- + * + * This function runs in a separate thread and waits for input to become + * available on a console. + * + * Results: + * None. + * + * Side effects: + * Signals the main thread when input become available. May cause the + * main thread to wake up by posting a message. May one line from the + * console for each wait operation. + * + *---------------------------------------------------------------------- + */ + +static DWORD WINAPI +ConsoleReaderThread( + LPVOID arg) +{ + ConsoleInfo *infoPtr = arg; + HANDLE *handle = infoPtr->handle; + ConsoleThreadInfo *threadInfo = &infoPtr->reader; + DWORD waitResult; + HANDLE wEvents[2]; + + /* + * The first event takes precedence. + */ + + wEvents[0] = threadInfo->stopEvent; + wEvents[1] = threadInfo->startEvent; + + for (;;) { + /* + * Wait for the main thread to signal before attempting to wait. + */ + + waitResult = WaitForMultipleObjects(2, wEvents, FALSE, INFINITE); + + if (waitResult != (WAIT_OBJECT_0 + 1)) { + /* + * The start event was not signaled. It must be the stop event or + * an error, so exit this thread. + */ + + break; + } + + /* + * Look for data on the console, but first ignore any events that are + * not KEY_EVENTs. + */ + + if (ReadConsoleBytes(handle, infoPtr->buffer, CONSOLE_BUFFER_SIZE, + (LPDWORD) &infoPtr->bytesRead) != FALSE) { + /* + * Data was stored in the buffer. + */ + + infoPtr->readFlags |= CONSOLE_BUFFERED; + } else { + DWORD err = GetLastError(); + + if (err == (DWORD) EOF) { + infoPtr->readFlags = CONSOLE_EOF; + } + } + + /* + * Signal the main thread by signalling the readable event and then + * waking up the notifier thread. + */ + + SetEvent(threadInfo->readyEvent); + + /* + * Alert the foreground thread. Note that we need to treat this like a + * critical section so the foreground thread does not terminate this + * thread while we are holding a mutex in the notifier code. + */ + + Tcl_MutexLock(&consoleMutex); + if (infoPtr->threadId != NULL) { + /* + * TIP #218. When in flight ignore the event, no one will receive + * it anyway. + */ + + Tcl_ThreadAlert(infoPtr->threadId); + } + Tcl_MutexUnlock(&consoleMutex); + } + + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleWriterThread -- + * + * This function runs in a separate thread and writes data onto a + * console. + * + * Results: + * Always returns 0. + * + * Side effects: + + * Signals the main thread when an output operation is completed. May + * cause the main thread to wake up by posting a message. + * + *---------------------------------------------------------------------- + */ + +static DWORD WINAPI +ConsoleWriterThread( + LPVOID arg) +{ + ConsoleInfo *infoPtr = arg; + HANDLE *handle = infoPtr->handle; + ConsoleThreadInfo *threadInfo = &infoPtr->writer; + DWORD count, toWrite, waitResult; + char *buf; + HANDLE wEvents[2]; + + /* + * The first event takes precedence. + */ + + wEvents[0] = threadInfo->stopEvent; + wEvents[1] = threadInfo->startEvent; + + for (;;) { + /* + * Wait for the main thread to signal before attempting to write. + */ + + waitResult = WaitForMultipleObjects(2, wEvents, FALSE, INFINITE); + + if (waitResult != (WAIT_OBJECT_0 + 1)) { + /* + * The start event was not signaled. It must be the stop event or + * an error, so exit this thread. + */ + + break; + } + + buf = infoPtr->writeBuf; + toWrite = infoPtr->toWrite; + + /* + * Loop until all of the bytes are written or an error occurs. + */ + + while (toWrite > 0) { + if (WriteConsoleBytes(handle, buf, (DWORD) toWrite, + &count) == FALSE) { + infoPtr->writeError = GetLastError(); + break; + } + toWrite -= count; + buf += count; + } + + /* + * Signal the main thread by signalling the writable event and then + * waking up the notifier thread. + */ + + SetEvent(threadInfo->readyEvent); + + /* + * Alert the foreground thread. Note that we need to treat this like a + * critical section so the foreground thread does not terminate this + * thread while we are holding a mutex in the notifier code. + */ + + Tcl_MutexLock(&consoleMutex); + if (infoPtr->threadId != NULL) { + /* + * TIP #218. When in flight ignore the event, no one will receive + * it anyway. + */ + + Tcl_ThreadAlert(infoPtr->threadId); + } + Tcl_MutexUnlock(&consoleMutex); + } + + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * TclWinOpenConsoleChannel -- + * + * Constructs a Console channel for the specified standard OS handle. + * This is a helper function to break up the construction of channels + * into File, Console, or Serial. + * + * Results: + * Returns the new channel, or NULL. + * + * Side effects: + * May open the channel. + * + *---------------------------------------------------------------------- + */ + +Tcl_Channel +TclWinOpenConsoleChannel( + HANDLE handle, + char *channelName, + int permissions) +{ + char encoding[4 + TCL_INTEGER_SPACE]; + ConsoleInfo *infoPtr; + DWORD modes; + + ConsoleInit(); + + /* + * See if a channel with this handle already exists. + */ + + infoPtr = ckalloc(sizeof(ConsoleInfo)); + memset(infoPtr, 0, sizeof(ConsoleInfo)); + + infoPtr->validMask = permissions; + infoPtr->handle = handle; + infoPtr->channel = (Tcl_Channel) NULL; + + wsprintfA(encoding, "cp%d", GetConsoleCP()); + + infoPtr->threadId = Tcl_GetCurrentThread(); + + /* + * Use the pointer for the name of the result channel. This keeps the + * channel names unique, since some may share handles (stdin/stdout/stderr + * for instance). + */ + + sprintf(channelName, "file%" TCL_I_MODIFIER "x", (size_t) infoPtr); + + infoPtr->channel = Tcl_CreateChannel(&consoleChannelType, channelName, + infoPtr, permissions); + + if (permissions & TCL_READABLE) { + /* + * Make sure the console input buffer is ready for only character + * input notifications and the buffer is set for line buffering. IOW, + * we only want to catch when complete lines are ready for reading. + */ + + GetConsoleMode(infoPtr->handle, &modes); + modes &= ~(ENABLE_WINDOW_INPUT | ENABLE_MOUSE_INPUT); + modes |= ENABLE_LINE_INPUT; + SetConsoleMode(infoPtr->handle, modes); + StartChannelThread(infoPtr, &infoPtr->reader, ConsoleReaderThread); + } + + if (permissions & TCL_WRITABLE) { + StartChannelThread(infoPtr, &infoPtr->writer, ConsoleWriterThread); + } + + /* + * Files have default translation of AUTO and ^Z eof char, which means + * that a ^Z will be accepted as EOF when reading. + */ + + Tcl_SetChannelOption(NULL, infoPtr->channel, "-translation", "auto"); + Tcl_SetChannelOption(NULL, infoPtr->channel, "-eofchar", "\032 {}"); +#ifdef UNICODE + Tcl_SetChannelOption(NULL, infoPtr->channel, "-encoding", "unicode"); +#else + Tcl_SetChannelOption(NULL, infoPtr->channel, "-encoding", encoding); +#endif + return infoPtr->channel; +} + +/* + *---------------------------------------------------------------------- + * + * ConsoleThreadActionProc -- + * + * Insert or remove any thread local refs to this channel. + * + * Results: + * None. + * + * Side effects: + * Changes thread local list of valid channels. + * + *---------------------------------------------------------------------- + */ + +static void +ConsoleThreadActionProc( + ClientData instanceData, + int action) +{ + ConsoleInfo *infoPtr = instanceData; + + /* + * We do not access firstConsolePtr in the thread structures. This is not + * for all serials managed by the thread, but only those we are watching. + * Removal of the filevent handlers before transfer thus takes care of + * this structure. + */ + + Tcl_MutexLock(&consoleMutex); + if (action == TCL_CHANNEL_THREAD_INSERT) { + /* + * We can't copy the thread information from the channel when the + * channel is created. At this time the channel back pointer has not + * been set yet. However in that case the threadId has already been + * set by TclpCreateCommandChannel itself, so the structure is still + * good. + */ + + ConsoleInit(); + if (infoPtr->channel != NULL) { + infoPtr->threadId = Tcl_GetChannelThread(infoPtr->channel); + } + } else { + infoPtr->threadId = NULL; + } + Tcl_MutexUnlock(&consoleMutex); +} + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |