diff options
Diffstat (limited to 'generic/tclIORChan.c')
| -rw-r--r-- | generic/tclIORChan.c | 3221 |
1 files changed, 0 insertions, 3221 deletions
diff --git a/generic/tclIORChan.c b/generic/tclIORChan.c deleted file mode 100644 index 49e2930..0000000 --- a/generic/tclIORChan.c +++ /dev/null @@ -1,3221 +0,0 @@ -/* - * tclIORChan.c -- - * - * This file contains the implementation of Tcl's generic channel - * reflection code, which allows the implementation of Tcl channels in - * Tcl code. - * - * Parts of this file are based on code contributed by Jean-Claude - * Wippler. - * - * See TIP #219 for the specification of this functionality. - * - * Copyright (c) 2004-2005 ActiveState, a divison of Sophos - * - * See the file "license.terms" for information on usage and redistribution of - * this file, and for a DISCLAIMER OF ALL WARRANTIES. - */ - -#include "tclInt.h" -#include "tclIO.h" -#include <assert.h> - -#ifndef EINVAL -#define EINVAL 9 -#endif -#ifndef EOK -#define EOK 0 -#endif - -/* - * Signatures of all functions used in the C layer of the reflection. - */ - -static int ReflectClose(ClientData clientData, - Tcl_Interp *interp); -static int ReflectInput(ClientData clientData, char *buf, - int toRead, int *errorCodePtr); -static int ReflectOutput(ClientData clientData, const char *buf, - int toWrite, int *errorCodePtr); -static void ReflectWatch(ClientData clientData, int mask); -static int ReflectBlock(ClientData clientData, int mode); -static Tcl_WideInt ReflectSeekWide(ClientData clientData, - Tcl_WideInt offset, int mode, int *errorCodePtr); -static int ReflectSeek(ClientData clientData, long offset, - int mode, int *errorCodePtr); -static int ReflectGetOption(ClientData clientData, - Tcl_Interp *interp, const char *optionName, - Tcl_DString *dsPtr); -static int ReflectSetOption(ClientData clientData, - Tcl_Interp *interp, const char *optionName, - const char *newValue); - -/* - * The C layer channel type/driver definition used by the reflection. This is - * a version 3 structure. - */ - -static const Tcl_ChannelType tclRChannelType = { - "tclrchannel", /* Type name. */ - TCL_CHANNEL_VERSION_5, /* v5 channel */ - ReflectClose, /* Close channel, clean instance data */ - ReflectInput, /* Handle read request */ - ReflectOutput, /* Handle write request */ - ReflectSeek, /* Move location of access point. NULL'able */ - ReflectSetOption, /* Set options. NULL'able */ - ReflectGetOption, /* Get options. NULL'able */ - ReflectWatch, /* Initialize notifier */ - NULL, /* Get OS handle from the channel. NULL'able */ - NULL, /* No close2 support. NULL'able */ - ReflectBlock, /* Set blocking/nonblocking. NULL'able */ - NULL, /* Flush channel. Not used by core. NULL'able */ - NULL, /* Handle events. NULL'able */ - ReflectSeekWide, /* Move access point (64 bit). NULL'able */ - NULL, /* thread action */ - NULL /* truncate */ -}; - -/* - * Instance data for a reflected channel. =========================== - */ - -typedef struct { - Tcl_Channel chan; /* Back reference to generic channel - * structure. */ - Tcl_Interp *interp; /* Reference to the interpreter containing the - * Tcl level part of the channel. NULL here - * signals the channel is dead because the - * interpreter/thread containing its Tcl - * command is gone. - */ -#ifdef TCL_THREADS - Tcl_ThreadId thread; /* Thread the 'interp' belongs to. */ -#endif - - /* See [==] as well. - * Storage for the command prefix and the additional words required for - * the invocation of methods in the command handler. - * - * argv [0] ... [.] | [argc-2] [argc-1] | [argc] [argc+2] - * cmd ... pfx | method chan | detail1 detail2 - * ~~~~ CT ~~~ ~~ CT ~~ - * - * CT = Belongs to the 'Command handler Thread'. - */ - - int argc; /* Number of preallocated words - 2 */ - Tcl_Obj **argv; /* Preallocated array for calling the handler. - * args[0] is placeholder for cmd word. - * Followed by the arguments in the prefix, - * plus 4 placeholders for method, channel, - * and at most two varying (method specific) - * words. */ - int methods; /* Bitmask of supported methods */ - - /* - * NOTE (9): Should we have predefined shared literals for the method - * names? - */ - - int mode; /* Mask of R/W mode */ - int interest; /* Mask of events the channel is interested - * in. */ - - int dead; /* Boolean signal that some operations - * should no longer be attempted. */ - - /* - * Note regarding the usage of timers. - * - * Most channel implementations need a timer in the C level to ensure that - * data in buffers is flushed out through the generation of fake file - * events. - * - * See 'rechan', 'memchan', etc. - * - * Here this is _not_ required. Interest in events is posted to the Tcl - * level via 'watch'. And posting of events is possible from the Tcl level - * as well, via 'chan postevent'. This means that the generation of all - * events, fake or not, timer based or not, is completely in the hands of - * the Tcl level. Therefore no timer here. - */ -} ReflectedChannel; - -/* - * Structure of the table maping from channel handles to reflected - * channels. Each interpreter which has the handler command for one or more - * reflected channels records them in such a table, so that 'chan postevent' - * is able to find them even if the actual channel was moved to a different - * interpreter and/or thread. - * - * The table is reachable via the standard interpreter AssocData, the key is - * defined below. - */ - -typedef struct { - Tcl_HashTable map; -} ReflectedChannelMap; - -#define RCMKEY "ReflectedChannelMap" - -/* - * Event literals. ================================================== - */ - -static const char *const eventOptions[] = { - "read", "write", NULL -}; -typedef enum { - EVENT_READ, EVENT_WRITE -} EventOption; - -/* - * Method literals. ================================================== - */ - -static const char *const methodNames[] = { - "blocking", /* OPT */ - "cget", /* OPT \/ Together or none */ - "cgetall", /* OPT /\ of these two */ - "configure", /* OPT */ - "finalize", /* */ - "initialize", /* */ - "read", /* OPT */ - "seek", /* OPT */ - "watch", /* */ - "write", /* OPT */ - NULL -}; -typedef enum { - METH_BLOCKING, - METH_CGET, - METH_CGETALL, - METH_CONFIGURE, - METH_FINAL, - METH_INIT, - METH_READ, - METH_SEEK, - METH_WATCH, - METH_WRITE -} MethodName; - -#define FLAG(m) (1 << (m)) -#define REQUIRED_METHODS \ - (FLAG(METH_INIT) | FLAG(METH_FINAL) | FLAG(METH_WATCH)) -#define NULLABLE_METHODS \ - (FLAG(METH_BLOCKING) | FLAG(METH_SEEK) | \ - FLAG(METH_CONFIGURE) | FLAG(METH_CGET) | FLAG(METH_CGETALL)) - -#define RANDW \ - (TCL_READABLE | TCL_WRITABLE) - -#define IMPLIES(a,b) ((!(a)) || (b)) -#define NEGIMPL(a,b) -#define HAS(x,f) (x & FLAG(f)) - -#ifdef TCL_THREADS -/* - * Thread specific types and structures. - * - * We are here essentially creating a very specific implementation of 'thread - * send'. - */ - -/* - * Enumeration of all operations which can be forwarded. - */ - -typedef enum { - ForwardedClose, - ForwardedInput, - ForwardedOutput, - ForwardedSeek, - ForwardedWatch, - ForwardedBlock, - ForwardedSetOpt, - ForwardedGetOpt, - ForwardedGetOptAll -} ForwardedOperation; - -/* - * Event used to forward driver invocations to the thread actually managing - * the channel. We cannot construct the command to execute and forward that. - * Because then it will contain a mixture of Tcl_Obj's belonging to both the - * command handler thread (CT), and the thread managing the channel (MT), - * executed in CT. Tcl_Obj's are not allowed to cross thread boundaries. So we - * forward an operation code, the argument details, and reference to results. - * The command is assembled in the CT and belongs fully to that thread. No - * sharing problems. - */ - -typedef struct ForwardParamBase { - int code; /* O: Ok/Fail of the cmd handler */ - char *msgStr; /* O: Error message for handler failure */ - int mustFree; /* O: True if msgStr is allocated, false if - * otherwise (static). */ -} ForwardParamBase; - -/* - * Operation specific parameter/result structures. (These are "subtypes" of - * ForwardParamBase. Where an operation does not need any special types, it - * has no "subtype" and just uses ForwardParamBase, as listed above.) - */ - -struct ForwardParamInput { - ForwardParamBase base; /* "Supertype". MUST COME FIRST. */ - char *buf; /* O: Where to store the read bytes */ - int toRead; /* I: #bytes to read, - * O: #bytes actually read */ -}; -struct ForwardParamOutput { - ForwardParamBase base; /* "Supertype". MUST COME FIRST. */ - const char *buf; /* I: Where the bytes to write come from */ - int toWrite; /* I: #bytes to write, - * O: #bytes actually written */ -}; -struct ForwardParamSeek { - ForwardParamBase base; /* "Supertype". MUST COME FIRST. */ - int seekMode; /* I: How to seek */ - Tcl_WideInt offset; /* I: Where to seek, - * O: New location */ -}; -struct ForwardParamWatch { - ForwardParamBase base; /* "Supertype". MUST COME FIRST. */ - int mask; /* I: What events to watch for */ -}; -struct ForwardParamBlock { - ForwardParamBase base; /* "Supertype". MUST COME FIRST. */ - int nonblocking; /* I: What mode to activate */ -}; -struct ForwardParamSetOpt { - ForwardParamBase base; /* "Supertype". MUST COME FIRST. */ - const char *name; /* Name of option to set */ - const char *value; /* Value to set */ -}; -struct ForwardParamGetOpt { - ForwardParamBase base; /* "Supertype". MUST COME FIRST. */ - const char *name; /* Name of option to get, maybe NULL */ - Tcl_DString *value; /* Result */ -}; - -/* - * Now join all these together in a single union for convenience. - */ - -typedef union ForwardParam { - ForwardParamBase base; - struct ForwardParamInput input; - struct ForwardParamOutput output; - struct ForwardParamSeek seek; - struct ForwardParamWatch watch; - struct ForwardParamBlock block; - struct ForwardParamSetOpt setOpt; - struct ForwardParamGetOpt getOpt; -} ForwardParam; - -/* - * Forward declaration. - */ - -typedef struct ForwardingResult ForwardingResult; - -/* - * General event structure, with reference to operation specific data. - */ - -typedef struct ForwardingEvent { - Tcl_Event event; /* Basic event data, has to be first item */ - ForwardingResult *resultPtr; - ForwardedOperation op; /* Forwarded driver operation */ - ReflectedChannel *rcPtr; /* Channel instance */ - ForwardParam *param; /* Packaged arguments and return values, a - * ForwardParam pointer. */ -} ForwardingEvent; - -/* - * Structure to manage the result of the forwarding. This is not the result of - * the operation itself, but about the success of the forward event itself. - * The event can be successful, even if the operation which was forwarded - * failed. It is also there to manage the synchronization between the involved - * threads. - */ - -struct ForwardingResult { - Tcl_ThreadId src; /* Originating thread. */ - Tcl_ThreadId dst; /* Thread the op was forwarded to. */ - Tcl_Interp *dsti; /* Interpreter in the thread the op was - * forwarded to. */ - /* - * Note regarding 'dsti' above: Its information is also available via the - * chain evPtr->rcPtr->interp, however, as can be seen, two more - * indirections are needed to retrieve it. And the evPtr may be gone, - * breaking the chain. - */ - Tcl_Condition done; /* Condition variable the forwarder blocks - * on. */ - int result; /* TCL_OK or TCL_ERROR */ - ForwardingEvent *evPtr; /* Event the result belongs to. */ - ForwardingResult *prevPtr, *nextPtr; - /* Links into the list of pending forwarded - * results. */ -}; - -typedef struct ThreadSpecificData { - /* - * Table of all reflected channels owned by this thread. This is the - * per-thread version of the per-interpreter map. - */ - - ReflectedChannelMap *rcmPtr; -} ThreadSpecificData; - -static Tcl_ThreadDataKey dataKey; - -/* - * List of forwarded operations which have not completed yet, plus the mutex - * to protect the access to this process global list. - */ - -static ForwardingResult *forwardList = NULL; -TCL_DECLARE_MUTEX(rcForwardMutex) - -/* - * Function containing the generic code executing a forward, and wrapper - * macros for the actual operations we wish to forward. Uses ForwardProc as - * the event function executed by the thread receiving a forwarding event - * (which executes the appropriate function and collects the result, if any). - * - * The ExitProc ensures that things do not deadlock when the sending thread - * involved in the forwarding exits. It also clean things up so that we don't - * leak resources when threads go away. - */ - -static void ForwardOpToOwnerThread(ReflectedChannel *rcPtr, - ForwardedOperation op, const void *param); -static int ForwardProc(Tcl_Event *evPtr, int mask); -static void SrcExitProc(ClientData clientData); - -#define FreeReceivedError(p) \ - if ((p)->base.mustFree) { \ - ckfree((p)->base.msgStr); \ - } -#define PassReceivedErrorInterp(i,p) \ - if ((i) != NULL) { \ - Tcl_SetChannelErrorInterp((i), \ - Tcl_NewStringObj((p)->base.msgStr, -1)); \ - } \ - FreeReceivedError(p) -#define PassReceivedError(c,p) \ - Tcl_SetChannelError((c), Tcl_NewStringObj((p)->base.msgStr, -1)); \ - FreeReceivedError(p) -#define ForwardSetStaticError(p,emsg) \ - (p)->base.code = TCL_ERROR; \ - (p)->base.mustFree = 0; \ - (p)->base.msgStr = (char *) (emsg) -#define ForwardSetDynamicError(p,emsg) \ - (p)->base.code = TCL_ERROR; \ - (p)->base.mustFree = 1; \ - (p)->base.msgStr = (char *) (emsg) - -static void ForwardSetObjError(ForwardParam *p, Tcl_Obj *objPtr); - -static ReflectedChannelMap * GetThreadReflectedChannelMap(void); -static void DeleteThreadReflectedChannelMap(ClientData clientData); - -#endif /* TCL_THREADS */ - -#define SetChannelErrorStr(c,msgStr) \ - Tcl_SetChannelError((c), Tcl_NewStringObj((msgStr), -1)) - -static Tcl_Obj * MarshallError(Tcl_Interp *interp); -static void UnmarshallErrorResult(Tcl_Interp *interp, - Tcl_Obj *msgObj); - -/* - * Static functions for this file: - */ - -static int EncodeEventMask(Tcl_Interp *interp, - const char *objName, Tcl_Obj *obj, int *mask); -static Tcl_Obj * DecodeEventMask(int mask); -static ReflectedChannel * NewReflectedChannel(Tcl_Interp *interp, - Tcl_Obj *cmdpfxObj, int mode, Tcl_Obj *handleObj); -static Tcl_Obj * NextHandle(void); -static void FreeReflectedChannel(ReflectedChannel *rcPtr); -static void FreeReflectedChannelArgs(ReflectedChannel *rcPtr); -static int InvokeTclMethod(ReflectedChannel *rcPtr, - const char *method, Tcl_Obj *argOneObj, - Tcl_Obj *argTwoObj, Tcl_Obj **resultObjPtr); - -static ReflectedChannelMap * GetReflectedChannelMap(Tcl_Interp *interp); -static void DeleteReflectedChannelMap(ClientData clientData, - Tcl_Interp *interp); -static int ErrnoReturn(ReflectedChannel *rcPtr, Tcl_Obj *resObj); - -/* - * Global constant strings (messages). ================== - * These string are used directly as bypass errors, thus they have to be valid - * Tcl lists where the last element is the message itself. Hence the - * list-quoting to keep the words of the message together. See also [x]. - */ - -static const char *msg_read_unsup = "{read not supported by Tcl driver}"; -static const char *msg_read_toomuch = "{read delivered more than requested}"; -static const char *msg_write_unsup = "{write not supported by Tcl driver}"; -static const char *msg_write_toomuch = "{write wrote more than requested}"; -static const char *msg_write_nothing = "{write wrote nothing}"; -static const char *msg_seek_beforestart = "{Tried to seek before origin}"; -#ifdef TCL_THREADS -static const char *msg_send_originlost = "{Channel thread lost}"; -static const char *msg_send_dstlost = "{Owner lost}"; -#endif /* TCL_THREADS */ -static const char *msg_dstlost = "-code 1 -level 0 -errorcode NONE -errorinfo {} -errorline 1 {Owner lost}"; - -/* - * Main methods to plug into the 'chan' ensemble'. ================== - */ - -/* - *---------------------------------------------------------------------- - * - * TclChanCreateObjCmd -- - * - * This function is invoked to process the "chan create" Tcl command. - * See the user documentation for details on what it does. - * - * Results: - * A standard Tcl result. The handle of the new channel is placed in the - * interp result. - * - * Side effects: - * Creates a new channel. - * - *---------------------------------------------------------------------- - */ - -int -TclChanCreateObjCmd( - ClientData clientData, - Tcl_Interp *interp, - int objc, - Tcl_Obj *const *objv) -{ - ReflectedChannel *rcPtr; /* Instance data of the new channel */ - Tcl_Obj *rcId; /* Handle of the new channel */ - int mode; /* R/W mode of new channel. Has to match - * abilities of handler commands */ - Tcl_Obj *cmdObj; /* Command prefix, list of words */ - Tcl_Obj *cmdNameObj; /* Command name */ - Tcl_Channel chan; /* Token for the new channel */ - Tcl_Obj *modeObj; /* mode in obj form for method call */ - int listc; /* Result of 'initialize', and of */ - Tcl_Obj **listv; /* its sublist in the 2nd element */ - int methIndex; /* Encoded method name */ - int result; /* Result code for 'initialize' */ - Tcl_Obj *resObj; /* Result data for 'initialize' */ - int methods; /* Bitmask for supported methods. */ - Channel *chanPtr; /* 'chan' resolved to internal struct. */ - Tcl_Obj *err; /* Error message */ - ReflectedChannelMap *rcmPtr; - /* Map of reflected channels with handlers in - * this interp. */ - Tcl_HashEntry *hPtr; /* Entry in the above map */ - int isNew; /* Placeholder. */ - - /* - * Syntax: chan create MODE CMDPREFIX - * [0] [1] [2] [3] - * - * Actually: rCreate MODE CMDPREFIX - * [0] [1] [2] - */ - -#define MODE (1) -#define CMD (2) - - /* - * Number of arguments... - */ - - if (objc != 3) { - Tcl_WrongNumArgs(interp, 1, objv, "mode cmdprefix"); - return TCL_ERROR; - } - - /* - * First argument is a list of modes. Allowed entries are "read", "write". - * Expect at least one list element. Abbreviations are ok. - */ - - modeObj = objv[MODE]; - if (EncodeEventMask(interp, "mode", objv[MODE], &mode) != TCL_OK) { - return TCL_ERROR; - } - - /* - * Second argument is command prefix, i.e. list of words, first word is - * name of handler command, other words are fixed arguments. Run the - * 'initialize' method to get the list of supported methods. Validate - * this. - */ - - cmdObj = objv[CMD]; - - /* - * Basic check that the command prefix truly is a list. - */ - - if (Tcl_ListObjIndex(interp, cmdObj, 0, &cmdNameObj) != TCL_OK) { - return TCL_ERROR; - } - - /* - * Now create the channel. - */ - - rcId = NextHandle(); - rcPtr = NewReflectedChannel(interp, cmdObj, mode, rcId); - chan = Tcl_CreateChannel(&tclRChannelType, TclGetString(rcId), rcPtr, - mode); - rcPtr->chan = chan; - chanPtr = (Channel *) chan; - - /* - * Invoke 'initialize' and validate that the handler is present and ok. - * Squash the channel if not. - * - * Note: The conversion of 'mode' back into a Tcl_Obj ensures that - * 'initialize' is invoked with canonical mode names, and no - * abbreviations. Using modeObj directly could feed abbreviations into the - * handler, and the handler is not specified to handle such. - */ - - modeObj = DecodeEventMask(mode); - /* assert modeObj.refCount == 1 */ - result = InvokeTclMethod(rcPtr, "initialize", modeObj, NULL, &resObj); - Tcl_DecrRefCount(modeObj); - - if (result != TCL_OK) { - UnmarshallErrorResult(interp, resObj); - Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */ - goto error; - } - - /* - * Verify the result. - * - List, of method names. Convert to mask. - * Check for non-optionals through the mask. - * Compare open mode against optional r/w. - */ - - if (Tcl_ListObjGetElements(NULL, resObj, &listc, &listv) != TCL_OK) { - Tcl_SetObjResult(interp, Tcl_ObjPrintf( - "chan handler \"%s initialize\" returned non-list: %s", - Tcl_GetString(cmdObj), Tcl_GetString(resObj))); - Tcl_DecrRefCount(resObj); - goto error; - } - - methods = 0; - while (listc > 0) { - if (Tcl_GetIndexFromObj(interp, listv[listc-1], methodNames, - "method", TCL_EXACT, &methIndex) != TCL_OK) { - TclNewLiteralStringObj(err, "chan handler \""); - Tcl_AppendObjToObj(err, cmdObj); - Tcl_AppendToObj(err, " initialize\" returned ", -1); - Tcl_AppendObjToObj(err, Tcl_GetObjResult(interp)); - Tcl_SetObjResult(interp, err); - Tcl_DecrRefCount(resObj); - goto error; - } - - methods |= FLAG(methIndex); - listc--; - } - Tcl_DecrRefCount(resObj); - - if ((REQUIRED_METHODS & methods) != REQUIRED_METHODS) { - Tcl_SetObjResult(interp, Tcl_ObjPrintf( - "chan handler \"%s\" does not support all required methods", - Tcl_GetString(cmdObj))); - goto error; - } - - if ((mode & TCL_READABLE) && !HAS(methods, METH_READ)) { - Tcl_SetObjResult(interp, Tcl_ObjPrintf( - "chan handler \"%s\" lacks a \"read\" method", - Tcl_GetString(cmdObj))); - goto error; - } - - if ((mode & TCL_WRITABLE) && !HAS(methods, METH_WRITE)) { - Tcl_SetObjResult(interp, Tcl_ObjPrintf( - "chan handler \"%s\" lacks a \"write\" method", - Tcl_GetString(cmdObj))); - goto error; - } - - if (!IMPLIES(HAS(methods, METH_CGET), HAS(methods, METH_CGETALL))) { - Tcl_SetObjResult(interp, Tcl_ObjPrintf( - "chan handler \"%s\" supports \"cget\" but not \"cgetall\"", - Tcl_GetString(cmdObj))); - goto error; - } - - if (!IMPLIES(HAS(methods, METH_CGETALL), HAS(methods, METH_CGET))) { - Tcl_SetObjResult(interp, Tcl_ObjPrintf( - "chan handler \"%s\" supports \"cgetall\" but not \"cget\"", - Tcl_GetString(cmdObj))); - goto error; - } - - Tcl_ResetResult(interp); - - /* - * Everything is fine now. - */ - - rcPtr->methods = methods; - - if ((methods & NULLABLE_METHODS) != NULLABLE_METHODS) { - /* - * Some of the nullable methods are not supported. We clone the - * channel type, null the associated C functions, and use the result - * as the actual channel type. - */ - - Tcl_ChannelType *clonePtr = ckalloc(sizeof(Tcl_ChannelType)); - - memcpy(clonePtr, &tclRChannelType, sizeof(Tcl_ChannelType)); - - if (!(methods & FLAG(METH_CONFIGURE))) { - clonePtr->setOptionProc = NULL; - } - - if (!(methods & FLAG(METH_CGET)) && !(methods & FLAG(METH_CGETALL))) { - clonePtr->getOptionProc = NULL; - } - if (!(methods & FLAG(METH_BLOCKING))) { - clonePtr->blockModeProc = NULL; - } - if (!(methods & FLAG(METH_SEEK))) { - clonePtr->seekProc = NULL; - clonePtr->wideSeekProc = NULL; - } - - chanPtr->typePtr = clonePtr; - } - - /* - * Register the channel in the I/O system, and in our our map for 'chan - * postevent'. - */ - - Tcl_RegisterChannel(interp, chan); - - rcmPtr = GetReflectedChannelMap(interp); - hPtr = Tcl_CreateHashEntry(&rcmPtr->map, chanPtr->state->channelName, - &isNew); - if (!isNew && chanPtr != Tcl_GetHashValue(hPtr)) { - Tcl_Panic("TclChanCreateObjCmd: duplicate channel names"); - } - Tcl_SetHashValue(hPtr, chan); -#ifdef TCL_THREADS - rcmPtr = GetThreadReflectedChannelMap(); - hPtr = Tcl_CreateHashEntry(&rcmPtr->map, chanPtr->state->channelName, - &isNew); - Tcl_SetHashValue(hPtr, chan); -#endif - - /* - * Return handle as result of command. - */ - - Tcl_SetResult(interp, (char *)chanPtr->state->channelName, TCL_VOLATILE); - return TCL_OK; - - error: - /* - * Signal to ReflectClose to not call 'finalize'. - */ - - rcPtr->methods = 0; - Tcl_Close(interp, chan); - return TCL_ERROR; - -#undef MODE -#undef CMD -} - -/* - *---------------------------------------------------------------------- - * - * TclChanPostEventObjCmd -- - * - * This function is invoked to process the "chan postevent" Tcl command. - * See the user documentation for details on what it does. - * - * Results: - * A standard Tcl result. - * - * Side effects: - * Posts events to a reflected channel, invokes event handlers. The - * latter implies that arbitrary side effects are possible. - * - *---------------------------------------------------------------------- - */ - -int -TclChanPostEventObjCmd( - ClientData clientData, - Tcl_Interp *interp, - int objc, - Tcl_Obj *const *objv) -{ - /* - * Syntax: chan postevent CHANNEL EVENTSPEC - * [0] [1] [2] [3] - * - * Actually: rPostevent CHANNEL EVENTSPEC - * [0] [1] [2] - * - * where EVENTSPEC = {read write ...} (Abbreviations allowed as well). - */ - -#define CHAN (1) -#define EVENT (2) - - const char *chanId; /* Tcl level channel handle */ - Tcl_Channel chan; /* Channel associated to the handle */ - const Tcl_ChannelType *chanTypePtr; - /* Its associated driver structure */ - ReflectedChannel *rcPtr; /* Associated instance data */ - int events; /* Mask of events to post */ - ReflectedChannelMap *rcmPtr;/* Map of reflected channels with handlers in - * this interp. */ - Tcl_HashEntry *hPtr; /* Entry in the above map */ - - /* - * Number of arguments... - */ - - if (objc != 3) { - Tcl_WrongNumArgs(interp, 1, objv, "channel eventspec"); - return TCL_ERROR; - } - - /* - * First argument is a channel, a reflected channel, and the call of this - * command is done from the interp defining the channel handler cmd. - */ - - chanId = TclGetString(objv[CHAN]); - - rcmPtr = GetReflectedChannelMap(interp); - hPtr = Tcl_FindHashEntry(&rcmPtr->map, chanId); - - if (hPtr == NULL) { - Tcl_AppendResult(interp, "can not find reflected channel named \"", - chanId, "\"", NULL); - Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "CHANNEL", chanId, NULL); - return TCL_ERROR; - } - - /* - * Note that the search above subsumes several of the older checks, namely: - * - * (1) Does the channel handle refer to a reflected channel ? - * (2) Is the post event issued from the interpreter holding the handler - * of the reflected channel ? - * - * A successful search answers yes to both. Because the map holds only - * handles of reflected channels, and only of such whose handler is - * defined in this interpreter. - * - * We keep the old checks for both, for paranioa, but abort now instead of - * throwing errors, as failure now means that our internal datastructures - * have gone seriously haywire. - */ - - chan = Tcl_GetHashValue(hPtr); - chanTypePtr = Tcl_GetChannelType(chan); - - /* - * We use a function referenced by the channel type as our cookie to - * detect calls to non-reflecting channels. The channel type itself is not - * suitable, as it might not be the static definition in this file, but a - * clone thereof. And while we have reserved the name of the type nothing - * in the core checks against violation, so someone else might have - * created a channel type using our name, clashing with ourselves. - */ - - if (chanTypePtr->watchProc != &ReflectWatch) { - Tcl_Panic("TclChanPostEventObjCmd: channel is not a reflected channel"); - } - - rcPtr = Tcl_GetChannelInstanceData(chan); - - if (rcPtr->interp != interp) { - Tcl_Panic("TclChanPostEventObjCmd: postevent accepted for call from outside interpreter"); - } - - /* - * Second argument is a list of events. Allowed entries are "read", - * "write". Expect at least one list element. Abbreviations are ok. - */ - - if (EncodeEventMask(interp, "event", objv[EVENT], &events) != TCL_OK) { - return TCL_ERROR; - } - - /* - * Check that the channel is actually interested in the provided events. - */ - - if (events & ~rcPtr->interest) { - Tcl_AppendResult(interp, "tried to post events channel \"", chanId, - "\" is not interested in", NULL); - return TCL_ERROR; - } - - /* - * We have the channel and the events to post. - */ - - Tcl_NotifyChannel(chan, events); - - /* - * Squash interp results left by the event script. - */ - - Tcl_ResetResult(interp); - return TCL_OK; - -#undef CHAN -#undef EVENT -} - -/* - * Channel error message marshalling utilities. - */ - -static Tcl_Obj * -MarshallError( - Tcl_Interp *interp) -{ - /* - * Capture the result status of the interpreter into a string. => List of - * options and values, followed by the error message. The result has - * refCount 0. - */ - - Tcl_Obj *returnOpt = Tcl_GetReturnOptions(interp, TCL_ERROR); - - /* - * => returnOpt.refCount == 0. We can append directly. - */ - - Tcl_ListObjAppendElement(NULL, returnOpt, Tcl_GetObjResult(interp)); - return returnOpt; -} - -static void -UnmarshallErrorResult( - Tcl_Interp *interp, - Tcl_Obj *msgObj) -{ - int lc; - Tcl_Obj **lv; - int explicitResult; - int numOptions; - - /* - * Process the caught message. - * - * Syntax = (option value)... ?message? - * - * Bad syntax causes a panic. This is OK because the other side uses - * Tcl_GetReturnOptions and list construction functions to marshall the - * information; if we panic here, something has gone badly wrong already. - */ - - if (Tcl_ListObjGetElements(interp, msgObj, &lc, &lv) != TCL_OK) { - Tcl_Panic("TclChanCaughtErrorBypass: Bad syntax of caught result"); - } - if (interp == NULL) { - return; - } - - explicitResult = lc & 1; /* Odd number of values? */ - numOptions = lc - explicitResult; - - if (explicitResult) { - Tcl_SetObjResult(interp, lv[lc-1]); - } - - (void) Tcl_SetReturnOptions(interp, Tcl_NewListObj(numOptions, lv)); - ((Interp *) interp)->flags &= ~ERR_ALREADY_LOGGED; -} - -int -TclChanCaughtErrorBypass( - Tcl_Interp *interp, - Tcl_Channel chan) -{ - Tcl_Obj *chanMsgObj = NULL; - Tcl_Obj *interpMsgObj = NULL; - Tcl_Obj *msgObj = NULL; - - /* - * Get a bypassed error message from channel and/or interpreter, save the - * reference, then kill the returned objects, if there were any. If there - * are messages in both the channel has preference. - */ - - if ((chan == NULL) && (interp == NULL)) { - return 0; - } - - if (chan != NULL) { - Tcl_GetChannelError(chan, &chanMsgObj); - } - if (interp != NULL) { - Tcl_GetChannelErrorInterp(interp, &interpMsgObj); - } - - if (chanMsgObj != NULL) { - msgObj = chanMsgObj; - } else if (interpMsgObj != NULL) { - msgObj = interpMsgObj; - } - if (msgObj != NULL) { - Tcl_IncrRefCount(msgObj); - } - - if (chanMsgObj != NULL) { - Tcl_DecrRefCount(chanMsgObj); - } - if (interpMsgObj != NULL) { - Tcl_DecrRefCount(interpMsgObj); - } - - /* - * No message returned, nothing caught. - */ - - if (msgObj == NULL) { - return 0; - } - - UnmarshallErrorResult(interp, msgObj); - - Tcl_DecrRefCount(msgObj); - return 1; -} - -/* - * Driver functions. ================================================ - */ - -/* - *---------------------------------------------------------------------- - * - * ReflectClose -- - * - * This function is invoked when the channel is closed, to delete the - * driver specific instance data. - * - * Results: - * A posix error. - * - * Side effects: - * Releases memory. Arbitrary, as it calls upon a script. - * - *---------------------------------------------------------------------- - */ - -static int -ReflectClose( - ClientData clientData, - Tcl_Interp *interp) -{ - ReflectedChannel *rcPtr = clientData; - int result; /* Result code for 'close' */ - Tcl_Obj *resObj; /* Result data for 'close' */ - ReflectedChannelMap *rcmPtr;/* Map of reflected channels with handlers in - * this interp */ - Tcl_HashEntry *hPtr; /* Entry in the above map */ - - if (TclInThreadExit()) { - /* - * This call comes from TclFinalizeIOSystem. There are no - * interpreters, and therefore we cannot call upon the handler command - * anymore. Threading is irrelevant as well. We simply clean up all - * our C level data structures and leave the Tcl level to the other - * finalization functions. - */ - - /* - * THREADED => Forward this to the origin thread - * - * Note: DeleteThreadReflectedChannelMap() is the thread exit handler - * for the origin thread. Use this to clean up the structure? Except - * if lost? - */ - -#ifdef TCL_THREADS - if (rcPtr->thread != Tcl_GetCurrentThread()) { - ForwardParam p; - - ForwardOpToOwnerThread(rcPtr, ForwardedClose, &p); - result = p.base.code; - - if (result != TCL_OK) { - FreeReceivedError(&p); - } - } -#endif - - Tcl_EventuallyFree (rcPtr, (Tcl_FreeProc *) FreeReflectedChannel); - return EOK; - } - - /* - * -- No -- ASSERT rcPtr->methods & FLAG(METH_FINAL) - * - * A cleaned method mask here implies that the channel creation was - * aborted, and "finalize" must not be called. - */ - - if (rcPtr->methods == 0) { - Tcl_EventuallyFree (rcPtr, (Tcl_FreeProc *) FreeReflectedChannel); - return EOK; - } - - /* - * Are we in the correct thread? - */ - -#ifdef TCL_THREADS - if (rcPtr->thread != Tcl_GetCurrentThread()) { - ForwardParam p; - - ForwardOpToOwnerThread(rcPtr, ForwardedClose, &p); - result = p.base.code; - - Tcl_EventuallyFree (rcPtr, (Tcl_FreeProc *) FreeReflectedChannel); - - if (result != TCL_OK) { - PassReceivedErrorInterp(interp, &p); - } - } else { -#endif - result = InvokeTclMethod(rcPtr, "finalize", NULL, NULL, &resObj); - if ((result != TCL_OK) && (interp != NULL)) { - Tcl_SetChannelErrorInterp(interp, resObj); - } - - Tcl_DecrRefCount(resObj); /* Remove reference we held from the - * invoke */ - - /* - * Remove the channel from the map before releasing the memory, to - * prevent future accesses (like by 'postevent') from finding and - * dereferencing a dangling pointer. - * - * NOTE: The channel may not be in the map. This is ok, that happens - * when the channel was created in a different interpreter and/or - * thread and then was moved here. - * - * NOTE: The channel may have been removed from the map already via - * the per-interp DeleteReflectedChannelMap exit-handler. - */ - - if (!rcPtr->dead) { - rcmPtr = GetReflectedChannelMap(rcPtr->interp); - hPtr = Tcl_FindHashEntry(&rcmPtr->map, - Tcl_GetChannelName(rcPtr->chan)); - if (hPtr) { - Tcl_DeleteHashEntry(hPtr); - } - } -#ifdef TCL_THREADS - rcmPtr = GetThreadReflectedChannelMap(); - hPtr = Tcl_FindHashEntry(&rcmPtr->map, - Tcl_GetChannelName(rcPtr->chan)); - if (hPtr) { - Tcl_DeleteHashEntry(hPtr); - } -#endif - - Tcl_EventuallyFree (rcPtr, (Tcl_FreeProc *) FreeReflectedChannel); -#ifdef TCL_THREADS - } -#endif - return (result == TCL_OK) ? EOK : EINVAL; -} - -/* - *---------------------------------------------------------------------- - * - * ReflectInput -- - * - * This function is invoked when more data is requested from the channel. - * - * Results: - * The number of bytes read. - * - * Side effects: - * Allocates memory. Arbitrary, as it calls upon a script. - * - *---------------------------------------------------------------------- - */ - -static int -ReflectInput( - ClientData clientData, - char *buf, - int toRead, - int *errorCodePtr) -{ - ReflectedChannel *rcPtr = clientData; - Tcl_Obj *toReadObj; - int bytec; /* Number of returned bytes */ - unsigned char *bytev; /* Array of returned bytes */ - Tcl_Obj *resObj; /* Result data for 'read' */ - - /* - * The following check can be done before thread redirection, because we - * are reading from an item which is readonly, i.e. will never change - * during the lifetime of the channel. - */ - - if (!(rcPtr->methods & FLAG(METH_READ))) { - SetChannelErrorStr(rcPtr->chan, msg_read_unsup); - *errorCodePtr = EINVAL; - return -1; - } - - /* - * Are we in the correct thread? - */ - -#ifdef TCL_THREADS - if (rcPtr->thread != Tcl_GetCurrentThread()) { - ForwardParam p; - - p.input.buf = buf; - p.input.toRead = toRead; - - ForwardOpToOwnerThread(rcPtr, ForwardedInput, &p); - - if (p.base.code != TCL_OK) { - if (p.base.code < 0) { - /* No error message, this is an errno signal. */ - *errorCodePtr = -p.base.code; - } else { - PassReceivedError(rcPtr->chan, &p); - *errorCodePtr = EINVAL; - } - p.input.toRead = -1; - } else { - *errorCodePtr = EOK; - } - - return p.input.toRead; - } -#endif - - /* ASSERT: rcPtr->method & FLAG(METH_READ) */ - /* ASSERT: rcPtr->mode & TCL_READABLE */ - - Tcl_Preserve(rcPtr); - - toReadObj = Tcl_NewIntObj(toRead); - Tcl_IncrRefCount(toReadObj); - - if (InvokeTclMethod(rcPtr, "read", toReadObj, NULL, &resObj)!=TCL_OK) { - int code = ErrnoReturn(rcPtr, resObj); - - if (code < 0) { - *errorCodePtr = -code; - goto error; - } - - Tcl_SetChannelError(rcPtr->chan, resObj); - goto invalid; - } - - bytev = Tcl_GetByteArrayFromObj(resObj, &bytec); - - if (toRead < bytec) { - SetChannelErrorStr(rcPtr->chan, msg_read_toomuch); - goto invalid; - } - - *errorCodePtr = EOK; - - if (bytec > 0) { - memcpy(buf, bytev, (size_t)bytec); - } - - stop: - Tcl_DecrRefCount(toReadObj); - Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */ - Tcl_Release(rcPtr); - return bytec; - invalid: - *errorCodePtr = EINVAL; - error: - bytec = -1; - goto stop; -} - -/* - *---------------------------------------------------------------------- - * - * ReflectOutput -- - * - * This function is invoked when data is writen to the channel. - * - * Results: - * The number of bytes actually written. - * - * Side effects: - * Allocates memory. Arbitrary, as it calls upon a script. - * - *---------------------------------------------------------------------- - */ - -static int -ReflectOutput( - ClientData clientData, - const char *buf, - int toWrite, - int *errorCodePtr) -{ - ReflectedChannel *rcPtr = clientData; - Tcl_Obj *bufObj; - Tcl_Obj *resObj; /* Result data for 'write' */ - int written; - - /* - * The following check can be done before thread redirection, because we - * are reading from an item which is readonly, i.e. will never change - * during the lifetime of the channel. - */ - - if (!(rcPtr->methods & FLAG(METH_WRITE))) { - SetChannelErrorStr(rcPtr->chan, msg_write_unsup); - *errorCodePtr = EINVAL; - return -1; - } - - /* - * Are we in the correct thread? - */ - -#ifdef TCL_THREADS - if (rcPtr->thread != Tcl_GetCurrentThread()) { - ForwardParam p; - - p.output.buf = buf; - p.output.toWrite = toWrite; - - ForwardOpToOwnerThread(rcPtr, ForwardedOutput, &p); - - if (p.base.code != TCL_OK) { - if (p.base.code < 0) { - /* No error message, this is an errno signal. */ - *errorCodePtr = -p.base.code; - } else { - PassReceivedError(rcPtr->chan, &p); - *errorCodePtr = EINVAL; - } - p.output.toWrite = -1; - } else { - *errorCodePtr = EOK; - } - - return p.output.toWrite; - } -#endif - - /* ASSERT: rcPtr->method & FLAG(METH_WRITE) */ - /* ASSERT: rcPtr->mode & TCL_WRITABLE */ - - Tcl_Preserve(rcPtr); - - bufObj = Tcl_NewByteArrayObj((unsigned char *) buf, toWrite); - Tcl_IncrRefCount(bufObj); - - if (InvokeTclMethod(rcPtr, "write", bufObj, NULL, &resObj) != TCL_OK) { - int code = ErrnoReturn(rcPtr, resObj); - - if (code < 0) { - *errorCodePtr = -code; - goto error; - } - - Tcl_SetChannelError(rcPtr->chan, resObj); - goto invalid; - } - - if (Tcl_GetIntFromObj(rcPtr->interp, resObj, &written) != TCL_OK) { - Tcl_SetChannelError(rcPtr->chan, MarshallError(rcPtr->interp)); - goto invalid; - } - - if ((written == 0) && (toWrite > 0)) { - /* - * The handler claims to have written nothing of what it was - * given. That is bad. - */ - - SetChannelErrorStr(rcPtr->chan, msg_write_nothing); - goto invalid; - } - if (toWrite < written) { - /* - * The handler claims to have written more than it was given. That is - * bad. Note that the I/O core would crash if we were to return this - * information, trying to write -nnn bytes in the next iteration. - */ - - SetChannelErrorStr(rcPtr->chan, msg_write_toomuch); - goto invalid; - } - - *errorCodePtr = EOK; - stop: - Tcl_DecrRefCount(bufObj); - Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */ - Tcl_Release(rcPtr); - return written; - invalid: - *errorCodePtr = EINVAL; - error: - written = -1; - goto stop; -} - -/* - *---------------------------------------------------------------------- - * - * ReflectSeekWide / ReflectSeek -- - * - * This function is invoked when the user wishes to seek on the channel. - * - * Results: - * The new location of the access point. - * - * Side effects: - * Allocates memory. Arbitrary, as it calls upon a script. - * - *---------------------------------------------------------------------- - */ - -static Tcl_WideInt -ReflectSeekWide( - ClientData clientData, - Tcl_WideInt offset, - int seekMode, - int *errorCodePtr) -{ - ReflectedChannel *rcPtr = clientData; - Tcl_Obj *offObj, *baseObj; - Tcl_Obj *resObj; /* Result for 'seek' */ - Tcl_WideInt newLoc; - - /* - * Are we in the correct thread? - */ - -#ifdef TCL_THREADS - if (rcPtr->thread != Tcl_GetCurrentThread()) { - ForwardParam p; - - p.seek.seekMode = seekMode; - p.seek.offset = offset; - - ForwardOpToOwnerThread(rcPtr, ForwardedSeek, &p); - - if (p.base.code != TCL_OK) { - PassReceivedError(rcPtr->chan, &p); - *errorCodePtr = EINVAL; - p.seek.offset = -1; - } else { - *errorCodePtr = EOK; - } - - return p.seek.offset; - } -#endif - - /* ASSERT: rcPtr->method & FLAG(METH_SEEK) */ - - Tcl_Preserve(rcPtr); - - offObj = Tcl_NewWideIntObj(offset); - baseObj = Tcl_NewStringObj((seekMode == SEEK_SET) ? "start" : - ((seekMode == SEEK_CUR) ? "current" : "end"), -1); - Tcl_IncrRefCount(offObj); - Tcl_IncrRefCount(baseObj); - - if (InvokeTclMethod(rcPtr, "seek", offObj, baseObj, &resObj)!=TCL_OK) { - Tcl_SetChannelError(rcPtr->chan, resObj); - goto invalid; - } - - if (Tcl_GetWideIntFromObj(rcPtr->interp, resObj, &newLoc) != TCL_OK) { - Tcl_SetChannelError(rcPtr->chan, MarshallError(rcPtr->interp)); - goto invalid; - } - - if (newLoc < Tcl_LongAsWide(0)) { - SetChannelErrorStr(rcPtr->chan, msg_seek_beforestart); - goto invalid; - } - - *errorCodePtr = EOK; - stop: - Tcl_DecrRefCount(offObj); - Tcl_DecrRefCount(baseObj); - Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */ - Tcl_Release(rcPtr); - return newLoc; - invalid: - *errorCodePtr = EINVAL; - newLoc = -1; - goto stop; -} - -static int -ReflectSeek( - ClientData clientData, - long offset, - int seekMode, - int *errorCodePtr) -{ - /* - * This function can be invoked from a transformation which is based on - * standard seeking, i.e. non-wide. Because of this we have to implement - * it, a dummy is not enough. We simply delegate the call to the wide - * routine. - */ - - return (int) ReflectSeekWide(clientData, Tcl_LongAsWide(offset), seekMode, - errorCodePtr); -} - -/* - *---------------------------------------------------------------------- - * - * ReflectWatch -- - * - * This function is invoked to tell the channel what events the I/O - * system is interested in. - * - * Results: - * None. - * - * Side effects: - * Allocates memory. Arbitrary, as it calls upon a script. - * - *---------------------------------------------------------------------- - */ - -static void -ReflectWatch( - ClientData clientData, - int mask) -{ - ReflectedChannel *rcPtr = clientData; - Tcl_Obj *maskObj; - - /* ASSERT rcPtr->methods & FLAG(METH_WATCH) */ - - /* - * We restrict the interest to what the channel can support. IOW there - * will never be write events for a channel which is not writable. - * Analoguously for read events and non-readable channels. - */ - - mask &= rcPtr->mode; - - if (mask == rcPtr->interest) { - /* - * Same old, same old, why should we do something? - */ - - return; - } - - rcPtr->interest = mask; - - /* - * Are we in the correct thread? - */ - -#ifdef TCL_THREADS - if (rcPtr->thread != Tcl_GetCurrentThread()) { - ForwardParam p; - - p.watch.mask = mask; - ForwardOpToOwnerThread(rcPtr, ForwardedWatch, &p); - - /* - * Any failure from the forward is ignored. We have no place to put - * this. - */ - - return; - } -#endif - - Tcl_Preserve(rcPtr); - - maskObj = DecodeEventMask(mask); - /* assert maskObj.refCount == 1 */ - (void) InvokeTclMethod(rcPtr, "watch", maskObj, NULL, NULL); - Tcl_DecrRefCount(maskObj); - - Tcl_Release(rcPtr); -} - -/* - *---------------------------------------------------------------------- - * - * ReflectBlock -- - * - * This function is invoked to tell the channel which blocking behaviour - * is required of it. - * - * Results: - * A posix error number. - * - * Side effects: - * Allocates memory. Arbitrary, as it calls upon a script. - * - *---------------------------------------------------------------------- - */ - -static int -ReflectBlock( - ClientData clientData, - int nonblocking) -{ - ReflectedChannel *rcPtr = clientData; - Tcl_Obj *blockObj; - int errorNum; /* EINVAL or EOK (success). */ - Tcl_Obj *resObj; /* Result data for 'blocking' */ - - /* - * Are we in the correct thread? - */ - -#ifdef TCL_THREADS - if (rcPtr->thread != Tcl_GetCurrentThread()) { - ForwardParam p; - - p.block.nonblocking = nonblocking; - - ForwardOpToOwnerThread(rcPtr, ForwardedBlock, &p); - - if (p.base.code != TCL_OK) { - PassReceivedError(rcPtr->chan, &p); - return EINVAL; - } - - return EOK; - } -#endif - - blockObj = Tcl_NewBooleanObj(!nonblocking); - Tcl_IncrRefCount(blockObj); - - Tcl_Preserve(rcPtr); - - if (InvokeTclMethod(rcPtr, "blocking", blockObj, NULL, &resObj)!=TCL_OK) { - Tcl_SetChannelError(rcPtr->chan, resObj); - errorNum = EINVAL; - } else { - errorNum = EOK; - } - - Tcl_DecrRefCount(blockObj); - Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */ - - Tcl_Release(rcPtr); - return errorNum; -} - -/* - *---------------------------------------------------------------------- - * - * ReflectSetOption -- - * - * This function is invoked to configure a channel option. - * - * Results: - * A standard Tcl result code. - * - * Side effects: - * Arbitrary, as it calls upon a Tcl script. - * - *---------------------------------------------------------------------- - */ - -static int -ReflectSetOption( - ClientData clientData, /* Channel to query */ - Tcl_Interp *interp, /* Interpreter to leave error messages in */ - const char *optionName, /* Name of requested option */ - const char *newValue) /* The new value */ -{ - ReflectedChannel *rcPtr = clientData; - Tcl_Obj *optionObj, *valueObj; - int result; /* Result code for 'configure' */ - Tcl_Obj *resObj; /* Result data for 'configure' */ - - /* - * Are we in the correct thread? - */ - -#ifdef TCL_THREADS - if (rcPtr->thread != Tcl_GetCurrentThread()) { - ForwardParam p; - - p.setOpt.name = optionName; - p.setOpt.value = newValue; - - ForwardOpToOwnerThread(rcPtr, ForwardedSetOpt, &p); - - if (p.base.code != TCL_OK) { - Tcl_Obj *err = Tcl_NewStringObj(p.base.msgStr, -1); - - UnmarshallErrorResult(interp, err); - Tcl_DecrRefCount(err); - FreeReceivedError(&p); - } - - return p.base.code; - } -#endif - Tcl_Preserve(rcPtr); - - optionObj = Tcl_NewStringObj(optionName, -1); - valueObj = Tcl_NewStringObj(newValue, -1); - - Tcl_IncrRefCount(optionObj); - Tcl_IncrRefCount(valueObj); - - result = InvokeTclMethod(rcPtr, "configure",optionObj,valueObj, &resObj); - if (result != TCL_OK) { - UnmarshallErrorResult(interp, resObj); - } - - Tcl_DecrRefCount(optionObj); - Tcl_DecrRefCount(valueObj); - Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */ - Tcl_Release(rcPtr); - return result; -} - -/* - *---------------------------------------------------------------------- - * - * ReflectGetOption -- - * - * This function is invoked to retrieve all or a channel option. - * - * Results: - * A standard Tcl result code. - * - * Side effects: - * Arbitrary, as it calls upon a Tcl script. - * - *---------------------------------------------------------------------- - */ - -static int -ReflectGetOption( - ClientData clientData, /* Channel to query */ - Tcl_Interp *interp, /* Interpreter to leave error messages in */ - const char *optionName, /* Name of reuqested option */ - Tcl_DString *dsPtr) /* String to place the result into */ -{ - /* - * This code is special. It has regular passing of Tcl result, and errors. - * The bypass functions are not required. - */ - - ReflectedChannel *rcPtr = clientData; - Tcl_Obj *optionObj; - Tcl_Obj *resObj; /* Result data for 'configure' */ - int listc, result = TCL_OK; - Tcl_Obj **listv; - const char *method; - - /* - * Are we in the correct thread? - */ - -#ifdef TCL_THREADS - if (rcPtr->thread != Tcl_GetCurrentThread()) { - int opcode; - ForwardParam p; - - p.getOpt.name = optionName; - p.getOpt.value = dsPtr; - - if (optionName == NULL) { - opcode = ForwardedGetOptAll; - } else { - opcode = ForwardedGetOpt; - } - - ForwardOpToOwnerThread(rcPtr, opcode, &p); - - if (p.base.code != TCL_OK) { - Tcl_Obj *err = Tcl_NewStringObj(p.base.msgStr, -1); - - UnmarshallErrorResult(interp, err); - Tcl_DecrRefCount(err); - FreeReceivedError(&p); - } - - return p.base.code; - } -#endif - - if (optionName == NULL) { - /* - * Retrieve all options. - */ - - method = "cgetall"; - optionObj = NULL; - } else { - /* - * Retrieve the value of one option. - */ - - method = "cget"; - optionObj = Tcl_NewStringObj(optionName, -1); - Tcl_IncrRefCount(optionObj); - } - - Tcl_Preserve(rcPtr); - - if (InvokeTclMethod(rcPtr, method, optionObj, NULL, &resObj)!=TCL_OK) { - UnmarshallErrorResult(interp, resObj); - goto error; - } - - /* - * The result has to go into the 'dsPtr' for propagation to the caller of - * the driver. - */ - - if (optionObj != NULL) { - Tcl_DStringAppend(dsPtr, TclGetString(resObj), -1); - goto ok; - } - - /* - * Extract the list and append each item as element. - */ - - /* - * NOTE (4): If we extract the string rep we can assume a properly quoted - * string. Together with a separating space this way of simply appending - * the whole string rep might be faster. It also doesn't check if the - * result is a valid list. Nor that the list has an even number elements. - */ - - if (Tcl_ListObjGetElements(interp, resObj, &listc, &listv) != TCL_OK) { - goto error; - } - - if ((listc % 2) == 1) { - /* - * Odd number of elements is wrong. - */ - - Tcl_ResetResult(interp); - Tcl_SetObjResult(interp, Tcl_ObjPrintf( - "Expected list with even number of " - "elements, got %d element%s instead", listc, - (listc == 1 ? "" : "s"))); - goto error; - } else { - int len; - const char *str = Tcl_GetStringFromObj(resObj, &len); - - if (len) { - Tcl_DStringAppend(dsPtr, " ", 1); - Tcl_DStringAppend(dsPtr, str, len); - } - goto ok; - } - - ok: - result = TCL_OK; - stop: - if (optionObj) { - Tcl_DecrRefCount(optionObj); - } - Tcl_DecrRefCount(resObj); /* Remove reference held from invoke */ - Tcl_Release(rcPtr); - return result; - error: - result = TCL_ERROR; - goto stop; -} - -/* - * Helpers. ========================================================= - */ - -/* - *---------------------------------------------------------------------- - * - * EncodeEventMask -- - * - * This function takes a list of event items and constructs the - * equivalent internal bitmask. The list must contain at least one - * element. Elements are "read", "write", or any unique abbreviation of - * them. Note that the bitmask is not changed if problems are - * encountered. - * - * Results: - * A standard Tcl error code. A bitmask where TCL_READABLE and/or - * TCL_WRITABLE can be set. - * - * Side effects: - * May shimmer 'obj' to a list representation. May place an error message - * into the interp result. - * - *---------------------------------------------------------------------- - */ - -static int -EncodeEventMask( - Tcl_Interp *interp, - const char *objName, - Tcl_Obj *obj, - int *mask) -{ - int events; /* Mask of events to post */ - int listc; /* #elements in eventspec list */ - Tcl_Obj **listv; /* Elements of eventspec list */ - int evIndex; /* Id of event for an element of the eventspec - * list. */ - - if (Tcl_ListObjGetElements(interp, obj, &listc, &listv) != TCL_OK) { - return TCL_ERROR; - } - - if (listc < 1) { - Tcl_AppendResult(interp, "bad ", objName, " list: is empty", NULL); - return TCL_ERROR; - } - - events = 0; - while (listc > 0) { - if (Tcl_GetIndexFromObj(interp, listv[listc-1], eventOptions, - objName, 0, &evIndex) != TCL_OK) { - return TCL_ERROR; - } - switch (evIndex) { - case EVENT_READ: - events |= TCL_READABLE; - break; - case EVENT_WRITE: - events |= TCL_WRITABLE; - break; - } - listc --; - } - - *mask = events; - return TCL_OK; -} - -/* - *---------------------------------------------------------------------- - * - * DecodeEventMask -- - * - * This function takes an internal bitmask of events and constructs the - * equivalent list of event items. - * - * Results, Contract: - * A Tcl_Obj reference. The object will have a refCount of one. The user - * has to decrement it to release the object. - * - * Side effects: - * None. - * - *---------------------------------------------------------------------- - */ - -static Tcl_Obj * -DecodeEventMask( - int mask) -{ - register const char *eventStr; - Tcl_Obj *evObj; - - switch (mask & RANDW) { - case RANDW: - eventStr = "read write"; - break; - case TCL_READABLE: - eventStr = "read"; - break; - case TCL_WRITABLE: - eventStr = "write"; - break; - default: - eventStr = ""; - break; - } - - evObj = Tcl_NewStringObj(eventStr, -1); - Tcl_IncrRefCount(evObj); - /* assert evObj.refCount == 1 */ - return evObj; -} - -/* - *---------------------------------------------------------------------- - * - * NewReflectedChannel -- - * - * This function is invoked to allocate and initialize the instance data - * of a new reflected channel. - * - * Results: - * A heap-allocated channel instance. - * - * Side effects: - * Allocates memory. - * - *---------------------------------------------------------------------- - */ - -static ReflectedChannel * -NewReflectedChannel( - Tcl_Interp *interp, - Tcl_Obj *cmdpfxObj, - int mode, - Tcl_Obj *handleObj) -{ - ReflectedChannel *rcPtr; - int i, listc; - Tcl_Obj **listv; - - rcPtr = ckalloc(sizeof(ReflectedChannel)); - - /* rcPtr->chan: Assigned by caller. Dummy data here. */ - /* rcPtr->methods: Assigned by caller. Dummy data here. */ - - rcPtr->chan = NULL; - rcPtr->methods = 0; - rcPtr->interp = interp; - rcPtr->dead = 0; -#ifdef TCL_THREADS - rcPtr->thread = Tcl_GetCurrentThread(); -#endif - rcPtr->mode = mode; - rcPtr->interest = 0; /* Initially no interest registered */ - - /* - * Method placeholder. - */ - - /* ASSERT: cmdpfxObj is a Tcl List */ - - Tcl_ListObjGetElements(interp, cmdpfxObj, &listc, &listv); - - /* - * See [==] as well. - * Storage for the command prefix and the additional words required for - * the invocation of methods in the command handler. - * - * listv [0] [listc-1] | [listc] [listc+1] | - * argv [0] ... [.] | [argc-2] [argc-1] | [argc] [argc+2] - * cmd ... pfx | method chan | detail1 detail2 - */ - - rcPtr->argc = listc + 2; - rcPtr->argv = ckalloc(sizeof(Tcl_Obj *) * (listc+4)); - - /* - * Duplicate object references. - */ - - for (i=0; i<listc ; i++) { - Tcl_Obj *word = rcPtr->argv[i] = listv[i]; - - Tcl_IncrRefCount(word); - } - - i++; /* Skip placeholder for method */ - - /* - * [Bug 1667990]: See [x] in FreeReflectedChannel for release - */ - - rcPtr->argv[i] = handleObj; - Tcl_IncrRefCount(handleObj); - - /* - * The next two objects are kept empty, varying arguments. - */ - - /* - * Initialization complete. - */ - - return rcPtr; -} - -/* - *---------------------------------------------------------------------- - * - * NextHandle -- - * - * This function is invoked to generate a channel handle for a new - * reflected channel. - * - * Results: - * A Tcl_Obj containing the string of the new channel handle. The - * refcount of the returned object is -- zero --. - * - * Side effects: - * May allocate memory. Mutex protected critical section locks out other - * threads for a short time. - * - *---------------------------------------------------------------------- - */ - -static Tcl_Obj * -NextHandle(void) -{ - /* - * Count number of generated reflected channels. Used for id generation. - * Ids are never reclaimed and there is no dealing with wrap around. On - * the other hand, "unsigned long" should be big enough except for - * absolute longrunners (generate a 100 ids per second => overflow will - * occur in 1 1/3 years). - */ - - TCL_DECLARE_MUTEX(rcCounterMutex) - static unsigned long rcCounter = 0; - Tcl_Obj *resObj; - - Tcl_MutexLock(&rcCounterMutex); - resObj = Tcl_ObjPrintf("rc%lu", rcCounter); - rcCounter++; - Tcl_MutexUnlock(&rcCounterMutex); - - return resObj; -} - -static void -FreeReflectedChannelArgs( - ReflectedChannel *rcPtr) -{ - int i, n = rcPtr->argc - 2; - - if (n < 0) { - return; - } - for (i=0; i<n; i++) { - Tcl_DecrRefCount(rcPtr->argv[i]); - } - - /* - * [Bug 1667990]: See [x] in NewReflectedChannel for lock. n+1 = argc-1. - */ - - Tcl_DecrRefCount(rcPtr->argv[n+1]); - - rcPtr->argc = 1; -} - -static void -FreeReflectedChannel( - ReflectedChannel *rcPtr) -{ - Channel *chanPtr = (Channel *) rcPtr->chan; - - if (chanPtr->typePtr != &tclRChannelType) { - /* - * Delete a cloned ChannelType structure. - */ - - ckfree(chanPtr->typePtr); - chanPtr->typePtr = NULL; - } - - FreeReflectedChannelArgs(rcPtr); - - ckfree(rcPtr->argv); - ckfree(rcPtr); -} - -/* - *---------------------------------------------------------------------- - * - * InvokeTclMethod -- - * - * This function is used to invoke the Tcl level of a reflected channel. - * It handles all the command assembly, invokation, and generic state and - * result mgmt. It does *not* handle thread redirection; that is the - * responsibility of clients of this function. - * - * Results: - * Result code and data as returned by the method. - * - * Side effects: - * Arbitrary, as it calls upon a Tcl script. - * - * Contract: - * argOneObj.refCount >= 1 on entry and exit, if argOneObj != NULL - * argTwoObj.refCount >= 1 on entry and exit, if argTwoObj != NULL - * resObj.refCount in {0, 1, ...} - * - *---------------------------------------------------------------------- - */ - -static int -InvokeTclMethod( - ReflectedChannel *rcPtr, - const char *method, - Tcl_Obj *argOneObj, /* NULL'able */ - Tcl_Obj *argTwoObj, /* NULL'able */ - Tcl_Obj **resultObjPtr) /* NULL'able */ -{ - int cmdc; /* #words in constructed command */ - Tcl_Obj *methObj = NULL; /* Method name in object form */ - Tcl_InterpState sr; /* State of handler interp */ - int result; /* Result code of method invokation */ - Tcl_Obj *resObj = NULL; /* Result of method invokation. */ - - if (rcPtr->dead) { - /* - * The channel is marked as dead. Bail out immediately, with an - * appropriate error. - */ - - if (resultObjPtr != NULL) { - resObj = Tcl_NewStringObj(msg_dstlost,-1); - *resultObjPtr = resObj; - Tcl_IncrRefCount(resObj); - } - - /* - * Not touching argOneObj, argTwoObj, they have not been used. - * See the contract as well. - */ - - return TCL_ERROR; - } - - /* - * NOTE (5): Decide impl. issue: Cache objects with method names? Needs - * TSD data as reflections can be created in many different threads. - * NO: Caching of command resolutions means storage per channel. - */ - - /* - * Insert method into the pre-allocated area, after the command prefix, - * before the channel id. - */ - - methObj = Tcl_NewStringObj(method, -1); - Tcl_IncrRefCount(methObj); - rcPtr->argv[rcPtr->argc - 2] = methObj; - - /* - * Append the additional argument containing method specific details - * behind the channel id. If specified. - * - * Because of the contract there is no need to increment the refcounts. - * The objects will survive the Tcl_EvalObjv without change. - */ - - cmdc = rcPtr->argc; - if (argOneObj) { - rcPtr->argv[cmdc] = argOneObj; - cmdc++; - if (argTwoObj) { - rcPtr->argv[cmdc] = argTwoObj; - cmdc++; - } - } - - /* - * And run the handler... This is done in auch a manner which leaves any - * existing state intact. - */ - - sr = Tcl_SaveInterpState(rcPtr->interp, 0 /* Dummy */); - Tcl_Preserve(rcPtr->interp); - result = Tcl_EvalObjv(rcPtr->interp, cmdc, rcPtr->argv, TCL_EVAL_GLOBAL); - - /* - * We do not try to extract the result information if the caller has no - * interest in it. I.e. there is no need to put effort into creating - * something which is discarded immediately after. - */ - - if (resultObjPtr) { - if (result == TCL_OK) { - /* - * Ok result taken as is, also if the caller requests that there - * is no capture. - */ - - resObj = Tcl_GetObjResult(rcPtr->interp); - } else { - /* - * Non-ok result is always treated as an error. We have to capture - * the full state of the result, including additional options. - * - * This is complex and ugly, and would be completely unnecessary - * if we only added support for a TCL_FORBID_EXCEPTIONS flag. - */ - - if (result != TCL_ERROR) { - Tcl_Obj *cmd = Tcl_NewListObj(cmdc, rcPtr->argv); - int cmdLen; - const char *cmdString = Tcl_GetStringFromObj(cmd, &cmdLen); - - Tcl_IncrRefCount(cmd); - Tcl_ResetResult(rcPtr->interp); - Tcl_SetObjResult(rcPtr->interp, Tcl_ObjPrintf( - "chan handler returned bad code: %d", result)); - Tcl_LogCommandInfo(rcPtr->interp, cmdString, cmdString, - cmdLen); - Tcl_DecrRefCount(cmd); - result = TCL_ERROR; - } - Tcl_AppendObjToErrorInfo(rcPtr->interp, Tcl_ObjPrintf( - "\n (chan handler subcommand \"%s\")", method)); - resObj = MarshallError(rcPtr->interp); - } - Tcl_IncrRefCount(resObj); - } - Tcl_RestoreInterpState(rcPtr->interp, sr); - Tcl_Release(rcPtr->interp); - - /* - * Cleanup of the dynamic parts of the command. - * - * The detail objects survived the Tcl_EvalObjv without change because of - * the contract. Therefore there is no need to decrement the refcounts. Only - * the internal method object has to be disposed of. - */ - - Tcl_DecrRefCount(methObj); - - /* - * The resObj has a ref count of 1 at this location. This means that the - * caller of InvokeTclMethod has to dispose of it (but only if it was - * returned to it). - */ - - if (resultObjPtr != NULL) { - *resultObjPtr = resObj; - } - - /* - * There no need to handle the case where nothing is returned, because for - * that case resObj was not set anyway. - */ - - return result; -} - -/* - *---------------------------------------------------------------------- - * - * ErrnoReturn -- - * - * Checks a method error result if it returned an 'errno'. - * - * Results: - * The negative errno found in the error result, or 0. - * - * Side effects: - * None. - * - * Users: - * ReflectInput/Output(), to enable the signaling of EAGAIN - * on 0-sized short reads/writes. - * - *---------------------------------------------------------------------- - */ - -static int -ErrnoReturn( - ReflectedChannel *rcPtr, - Tcl_Obj *resObj) -{ - int code; - Tcl_InterpState sr; /* State of handler interp */ - - if (rcPtr->dead) { - return 0; - } - - sr = Tcl_SaveInterpState(rcPtr->interp, 0 /* Dummy */); - UnmarshallErrorResult(rcPtr->interp, resObj); - - resObj = Tcl_GetObjResult(rcPtr->interp); - - if (((Tcl_GetIntFromObj(rcPtr->interp, resObj, &code) != TCL_OK) - || (code >= 0))) { - if (strcmp("EAGAIN", Tcl_GetString(resObj)) == 0) { - code = -EAGAIN; - } else { - code = 0; - } - } - - Tcl_RestoreInterpState(rcPtr->interp, sr); - return code; -} - -/* - *---------------------------------------------------------------------- - * - * GetReflectedChannelMap -- - * - * Gets and potentially initializes the reflected channel map for an - * interpreter. - * - * Results: - * A pointer to the map created, for use by the caller. - * - * Side effects: - * Initializes the reflected channel map for an interpreter. - * - *---------------------------------------------------------------------- - */ - -static ReflectedChannelMap * -GetReflectedChannelMap( - Tcl_Interp *interp) -{ - ReflectedChannelMap *rcmPtr = Tcl_GetAssocData(interp, RCMKEY, NULL); - - if (rcmPtr == NULL) { - rcmPtr = ckalloc(sizeof(ReflectedChannelMap)); - Tcl_InitHashTable(&rcmPtr->map, TCL_STRING_KEYS); - Tcl_SetAssocData(interp, RCMKEY, - (Tcl_InterpDeleteProc *) DeleteReflectedChannelMap, rcmPtr); - } - return rcmPtr; -} - -/* - *---------------------------------------------------------------------- - * - * DeleteReflectedChannelMap -- - * - * 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 -DeleteReflectedChannelMap( - ClientData clientData, /* The per-interpreter data structure. */ - Tcl_Interp *interp) /* The interpreter being deleted. */ -{ - ReflectedChannelMap *rcmPtr = clientData; - /* The map */ - Tcl_HashSearch hSearch; /* Search variable. */ - Tcl_HashEntry *hPtr; /* Search variable. */ - ReflectedChannel *rcPtr; - Tcl_Channel chan; -#ifdef TCL_THREADS - ForwardingResult *resultPtr; - ForwardingEvent *evPtr; - ForwardParam *paramPtr; -#endif - - /* - * Delete all entries. The channels may have been closed already, or will - * be closed later, by the standard IO finalization of an interpreter - * under destruction. Except for the channels which were moved to a - * different interpreter and/or thread. They do not exist from the IO - * systems point of view and will not get closed. Therefore mark all as - * dead so that any future access will cause a proper error. For channels - * in a different thread we actually do the same as - * DeleteThreadReflectedChannelMap(), just restricted to the channels of - * this interp. - */ - - for (hPtr = Tcl_FirstHashEntry(&rcmPtr->map, &hSearch); - hPtr != NULL; - hPtr = Tcl_FirstHashEntry(&rcmPtr->map, &hSearch)) { - chan = Tcl_GetHashValue(hPtr); - rcPtr = Tcl_GetChannelInstanceData(chan); - - rcPtr->dead = 1; - Tcl_DeleteHashEntry(hPtr); - } - Tcl_DeleteHashTable(&rcmPtr->map); - ckfree(&rcmPtr->map); - -#ifdef TCL_THREADS - /* - * The origin interpreter for one or more reflected channels is gone. - */ - - /* - * Go through the list of pending results and cancel all whose events were - * destined for this interpreter. While this is in progress we block any - * other access to the list of pending results. - */ - - Tcl_MutexLock(&rcForwardMutex); - - for (resultPtr = forwardList; - resultPtr != NULL; - resultPtr = resultPtr->nextPtr) { - if (resultPtr->dsti != interp) { - /* - * Ignore results/events for other interpreters. - */ - - continue; - } - - /* - * The receiver for the event exited, before processing the event. We - * detach the result now, wake the originator up and signal failure. - */ - - evPtr = resultPtr->evPtr; - - /* Basic crash safety until this routine can get revised [3411310] */ - if (evPtr == NULL) { - continue; - } - paramPtr = evPtr->param; - - evPtr->resultPtr = NULL; - resultPtr->evPtr = NULL; - resultPtr->result = TCL_ERROR; - - ForwardSetStaticError(paramPtr, msg_send_dstlost); - - Tcl_ConditionNotify(&resultPtr->done); - } - Tcl_MutexUnlock(&rcForwardMutex); - - /* - * Get the map of all channels handled by the current thread. This is a - * ReflectedChannelMap, but on a per-thread basis, not per-interp. Go - * through the channels and remove all which were handled by this - * interpreter. They have already been marked as dead. - */ - - rcmPtr = GetThreadReflectedChannelMap(); - for (hPtr = Tcl_FirstHashEntry(&rcmPtr->map, &hSearch); - hPtr != NULL; - hPtr = Tcl_NextHashEntry(&hSearch)) { - chan = Tcl_GetHashValue(hPtr); - rcPtr = Tcl_GetChannelInstanceData(chan); - - if (rcPtr->interp != interp) { - /* - * Ignore entries for other interpreters. - */ - - continue; - } - - rcPtr->dead = 1; - FreeReflectedChannelArgs(rcPtr); - Tcl_DeleteHashEntry(hPtr); - } -#endif -} - -#ifdef TCL_THREADS -/* - *---------------------------------------------------------------------- - * - * GetThreadReflectedChannelMap -- - * - * Gets and potentially initializes the reflected channel map for a - * thread. - * - * Results: - * A pointer to the map created, for use by the caller. - * - * Side effects: - * Initializes the reflected channel map for a thread. - * - *---------------------------------------------------------------------- - */ - -static ReflectedChannelMap * -GetThreadReflectedChannelMap(void) -{ - ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); - - if (!tsdPtr->rcmPtr) { - tsdPtr->rcmPtr = ckalloc(sizeof(ReflectedChannelMap)); - Tcl_InitHashTable(&tsdPtr->rcmPtr->map, TCL_STRING_KEYS); - Tcl_CreateThreadExitHandler(DeleteThreadReflectedChannelMap, NULL); - } - - return tsdPtr->rcmPtr; -} - -/* - *---------------------------------------------------------------------- - * - * DeleteThreadReflectedChannelMap -- - * - * Deletes the channel table for a thread. This procedure is invoked when - * a thread is deleted. The channels have already been marked as dead, in - * DeleteReflectedChannelMap(). - * - * Results: - * None. - * - * Side effects: - * Deletes the hash table of channels. - * - *---------------------------------------------------------------------- - */ - -static void -DeleteThreadReflectedChannelMap( - ClientData clientData) /* The per-thread data structure. */ -{ - Tcl_HashSearch hSearch; /* Search variable. */ - Tcl_HashEntry *hPtr; /* Search variable. */ - Tcl_ThreadId self = Tcl_GetCurrentThread(); - ReflectedChannelMap *rcmPtr; /* The map */ - ForwardingResult *resultPtr; - - /* - * The origin thread for one or more reflected channels is gone. - * NOTE: If this function is called due to a thread getting killed the - * per-interp DeleteReflectedChannelMap is apparently not called. - */ - - /* - * Go through the list of pending results and cancel all whose events were - * destined for this thread. While this is in progress we block any - * other access to the list of pending results. - */ - - Tcl_MutexLock(&rcForwardMutex); - - for (resultPtr = forwardList; - resultPtr != NULL; - resultPtr = resultPtr->nextPtr) { - ForwardingEvent *evPtr; - ForwardParam *paramPtr; - - if (resultPtr->dst != self) { - /* - * Ignore results/events for other threads. - */ - - continue; - } - - /* - * The receiver for the event exited, before processing the event. We - * detach the result now, wake the originator up and signal failure. - */ - - evPtr = resultPtr->evPtr; - - /* Basic crash safety until this routine can get revised [3411310] */ - if (evPtr == NULL ) { - continue; - } - paramPtr = evPtr->param; - - evPtr->resultPtr = NULL; - resultPtr->evPtr = NULL; - resultPtr->result = TCL_ERROR; - - ForwardSetStaticError(paramPtr, msg_send_dstlost); - - Tcl_ConditionNotify(&resultPtr->done); - } - Tcl_MutexUnlock(&rcForwardMutex); - - /* - * Get the map of all channels handled by the current thread. This is a - * ReflectedChannelMap, but on a per-thread basis, not per-interp. Go - * through the channels, remove all, mark them as dead. - */ - - rcmPtr = GetThreadReflectedChannelMap(); - for (hPtr = Tcl_FirstHashEntry(&rcmPtr->map, &hSearch); - hPtr != NULL; - hPtr = Tcl_FirstHashEntry(&rcmPtr->map, &hSearch)) { - Tcl_Channel chan = Tcl_GetHashValue(hPtr); - ReflectedChannel *rcPtr = Tcl_GetChannelInstanceData(chan); - - rcPtr->dead = 1; - FreeReflectedChannelArgs(rcPtr); - Tcl_DeleteHashEntry(hPtr); - } - ckfree(rcmPtr); -} - -static void -ForwardOpToOwnerThread( - ReflectedChannel *rcPtr, /* Channel instance */ - ForwardedOperation op, /* Forwarded driver operation */ - const void *param) /* Arguments */ -{ - Tcl_ThreadId dst = rcPtr->thread; - ForwardingEvent *evPtr; - ForwardingResult *resultPtr; - - /* - * We gather the lock early. This allows us to check the liveness of the - * channel without interference from DeleteThreadReflectedChannelMap(). - */ - - Tcl_MutexLock(&rcForwardMutex); - - if (rcPtr->dead) { - /* - * The channel is marked as dead. Bail out immediately, with an - * appropriate error. Do not forget to unlock the mutex on this path. - */ - - ForwardSetStaticError((ForwardParam *) param, msg_send_dstlost); - Tcl_MutexUnlock(&rcForwardMutex); - return; - } - - /* - * Create and initialize the event and data structures. - */ - - evPtr = ckalloc(sizeof(ForwardingEvent)); - resultPtr = ckalloc(sizeof(ForwardingResult)); - - evPtr->event.proc = ForwardProc; - evPtr->resultPtr = resultPtr; - evPtr->op = op; - evPtr->rcPtr = rcPtr; - evPtr->param = (ForwardParam *) param; - - resultPtr->src = Tcl_GetCurrentThread(); - resultPtr->dst = dst; - resultPtr->dsti = rcPtr->interp; - resultPtr->done = NULL; - resultPtr->result = -1; - resultPtr->evPtr = evPtr; - - /* - * Now execute the forward. - */ - - TclSpliceIn(resultPtr, forwardList); - /* Do not unlock here. That is done by the ConditionWait */ - - /* - * Ensure cleanup of the event if the origin thread exits while this event - * is pending or in progress. Exit of the destination thread is handled by - * DeleteThreadReflectionChannelMap(), this is set up by - * GetThreadReflectedChannelMap(). This is what we use the 'forwardList' - * (see above) for. - */ - - Tcl_CreateThreadExitHandler(SrcExitProc, evPtr); - - /* - * Queue the event and poke the other thread's notifier. - */ - - Tcl_ThreadQueueEvent(dst, (Tcl_Event *) evPtr, TCL_QUEUE_TAIL); - Tcl_ThreadAlert(dst); - - /* - * (*) Block until the other thread has either processed the transfer or - * rejected it. - */ - - while (resultPtr->result < 0) { - /* - * NOTE (1): Is it possible that the current thread goes away while - * waiting here? IOW Is it possible that "SrcExitProc" is called while - * we are here? See complementary note (2) in "SrcExitProc" - * - * The ConditionWait unlocks the mutex during the wait and relocks it - * immediately after. - */ - - Tcl_ConditionWait(&resultPtr->done, &rcForwardMutex, NULL); - } - - /* - * Unlink result from the forwarder list. No need to lock. Either still - * locked, or locked by the ConditionWait - */ - - TclSpliceOut(resultPtr, forwardList); - - resultPtr->nextPtr = NULL; - resultPtr->prevPtr = NULL; - - Tcl_MutexUnlock(&rcForwardMutex); - Tcl_ConditionFinalize(&resultPtr->done); - - /* - * Kill the cleanup handler now, and the result structure as well, before - * returning the success code. - * - * Note: The event structure has already been deleted. - */ - - Tcl_DeleteThreadExitHandler(SrcExitProc, evPtr); - - ckfree(resultPtr); -} - -static int -ForwardProc( - Tcl_Event *evGPtr, - int mask) -{ - /* - * Notes regarding access to the referenced data. - * - * In principle the data belongs to the originating thread (see - * evPtr->src), however this thread is currently blocked at (*), i.e. - * quiescent. Because of this we can treat the data as belonging to us, - * without fear of race conditions. I.e. we can read and write as we like. - * - * The only thing we cannot be sure of is the resultPtr. This can be be - * NULLed if the originating thread went away while the event is handled - * here now. - */ - - ForwardingEvent *evPtr = (ForwardingEvent *) evGPtr; - ForwardingResult *resultPtr = evPtr->resultPtr; - ReflectedChannel *rcPtr = evPtr->rcPtr; - Tcl_Interp *interp = rcPtr->interp; - ForwardParam *paramPtr = evPtr->param; - Tcl_Obj *resObj = NULL; /* Interp result of InvokeTclMethod */ - ReflectedChannelMap *rcmPtr; - /* Map of reflected channels with handlers in - * this interp. */ - Tcl_HashEntry *hPtr; /* Entry in the above map */ - - /* - * Ignore the event if no one is waiting for its result anymore. - */ - - if (!resultPtr) { - return 1; - } - - paramPtr->base.code = TCL_OK; - paramPtr->base.msgStr = NULL; - paramPtr->base.mustFree = 0; - - switch (evPtr->op) { - /* - * The destination thread for the following operations is - * rcPtr->thread, which contains rcPtr->interp, the interp we have to - * call upon for the driver. - */ - - case ForwardedClose: - /* - * No parameters/results. - */ - - if (InvokeTclMethod(rcPtr, "finalize", NULL, NULL, &resObj)!=TCL_OK) { - ForwardSetObjError(paramPtr, resObj); - } - - /* - * Freeing is done here, in the origin thread, because the argv[] - * objects belong to this thread. Deallocating them in a different - * thread is not allowed - * - * We remove the channel from both interpreter and thread maps before - * releasing the memory, to prevent future accesses (like by - * 'postevent') from finding and dereferencing a dangling pointer. - */ - - rcmPtr = GetReflectedChannelMap(interp); - hPtr = Tcl_FindHashEntry(&rcmPtr->map, - Tcl_GetChannelName(rcPtr->chan)); - Tcl_DeleteHashEntry(hPtr); - - rcmPtr = GetThreadReflectedChannelMap(); - hPtr = Tcl_FindHashEntry(&rcmPtr->map, - Tcl_GetChannelName(rcPtr->chan)); - Tcl_DeleteHashEntry(hPtr); - - FreeReflectedChannelArgs(rcPtr); - break; - - case ForwardedInput: { - Tcl_Obj *toReadObj = Tcl_NewIntObj(paramPtr->input.toRead); - Tcl_IncrRefCount(toReadObj); - - Tcl_Preserve(rcPtr); - if (InvokeTclMethod(rcPtr, "read", toReadObj, NULL, &resObj)!=TCL_OK){ - int code = ErrnoReturn(rcPtr, resObj); - - if (code < 0) { - paramPtr->base.code = code; - } else { - ForwardSetObjError(paramPtr, resObj); - } - paramPtr->input.toRead = -1; - } else { - /* - * Process a regular result. - */ - - int bytec; /* Number of returned bytes */ - unsigned char *bytev; /* Array of returned bytes */ - - bytev = Tcl_GetByteArrayFromObj(resObj, &bytec); - - if (paramPtr->input.toRead < bytec) { - ForwardSetStaticError(paramPtr, msg_read_toomuch); - paramPtr->input.toRead = -1; - } else { - if (bytec > 0) { - memcpy(paramPtr->input.buf, bytev, (size_t)bytec); - } - paramPtr->input.toRead = bytec; - } - } - Tcl_Release(rcPtr); - Tcl_DecrRefCount(toReadObj); - break; - } - - case ForwardedOutput: { - Tcl_Obj *bufObj = Tcl_NewByteArrayObj((unsigned char *) - paramPtr->output.buf, paramPtr->output.toWrite); - Tcl_IncrRefCount(bufObj); - - Tcl_Preserve(rcPtr); - if (InvokeTclMethod(rcPtr, "write", bufObj, NULL, &resObj) != TCL_OK) { - int code = ErrnoReturn(rcPtr, resObj); - - if (code < 0) { - paramPtr->base.code = code; - } else { - ForwardSetObjError(paramPtr, resObj); - } - paramPtr->output.toWrite = -1; - } else { - /* - * Process a regular result. - */ - - int written; - - if (Tcl_GetIntFromObj(interp, resObj, &written) != TCL_OK) { - Tcl_DecrRefCount(resObj); - resObj = MarshallError(interp); - ForwardSetObjError(paramPtr, resObj); - paramPtr->output.toWrite = -1; - } else if (written==0 || paramPtr->output.toWrite<written) { - ForwardSetStaticError(paramPtr, msg_write_toomuch); - paramPtr->output.toWrite = -1; - } else { - paramPtr->output.toWrite = written; - } - } - Tcl_Release(rcPtr); - Tcl_DecrRefCount(bufObj); - break; - } - - case ForwardedSeek: { - Tcl_Obj *offObj = Tcl_NewWideIntObj(paramPtr->seek.offset); - Tcl_Obj *baseObj = Tcl_NewStringObj( - (paramPtr->seek.seekMode==SEEK_SET) ? "start" : - (paramPtr->seek.seekMode==SEEK_CUR) ? "current" : "end", -1); - - Tcl_IncrRefCount(offObj); - Tcl_IncrRefCount(baseObj); - - Tcl_Preserve(rcPtr); - if (InvokeTclMethod(rcPtr, "seek", offObj, baseObj, &resObj)!=TCL_OK){ - ForwardSetObjError(paramPtr, resObj); - paramPtr->seek.offset = -1; - } else { - /* - * Process a regular result. If the type is wrong this may change - * into an error. - */ - - Tcl_WideInt newLoc; - - if (Tcl_GetWideIntFromObj(interp, resObj, &newLoc) == TCL_OK) { - if (newLoc < Tcl_LongAsWide(0)) { - ForwardSetStaticError(paramPtr, msg_seek_beforestart); - paramPtr->seek.offset = -1; - } else { - paramPtr->seek.offset = newLoc; - } - } else { - Tcl_DecrRefCount(resObj); - resObj = MarshallError(interp); - ForwardSetObjError(paramPtr, resObj); - paramPtr->seek.offset = -1; - } - } - Tcl_Release(rcPtr); - Tcl_DecrRefCount(offObj); - Tcl_DecrRefCount(baseObj); - break; - } - - case ForwardedWatch: { - Tcl_Obj *maskObj = DecodeEventMask(paramPtr->watch.mask); - /* assert maskObj.refCount == 1 */ - - Tcl_Preserve(rcPtr); - (void) InvokeTclMethod(rcPtr, "watch", maskObj, NULL, NULL); - Tcl_DecrRefCount(maskObj); - Tcl_Release(rcPtr); - break; - } - - case ForwardedBlock: { - Tcl_Obj *blockObj = Tcl_NewBooleanObj(!paramPtr->block.nonblocking); - Tcl_IncrRefCount(blockObj); - - Tcl_Preserve(rcPtr); - if (InvokeTclMethod(rcPtr, "blocking", blockObj, NULL, - &resObj) != TCL_OK) { - ForwardSetObjError(paramPtr, resObj); - } - Tcl_Release(rcPtr); - Tcl_DecrRefCount(blockObj); - break; - } - - case ForwardedSetOpt: { - Tcl_Obj *optionObj = Tcl_NewStringObj(paramPtr->setOpt.name, -1); - Tcl_Obj *valueObj = Tcl_NewStringObj(paramPtr->setOpt.value, -1); - - Tcl_IncrRefCount(optionObj); - Tcl_IncrRefCount(valueObj); - Tcl_Preserve(rcPtr); - if (InvokeTclMethod(rcPtr, "configure", optionObj, valueObj, - &resObj) != TCL_OK) { - ForwardSetObjError(paramPtr, resObj); - } - Tcl_Release(rcPtr); - Tcl_DecrRefCount(optionObj); - Tcl_DecrRefCount(valueObj); - break; - } - - case ForwardedGetOpt: { - /* - * Retrieve the value of one option. - */ - - Tcl_Obj *optionObj = Tcl_NewStringObj(paramPtr->getOpt.name, -1); - Tcl_IncrRefCount(optionObj); - - Tcl_Preserve(rcPtr); - if (InvokeTclMethod(rcPtr, "cget", optionObj, NULL, &resObj)!=TCL_OK){ - ForwardSetObjError(paramPtr, resObj); - } else { - Tcl_DStringAppend(paramPtr->getOpt.value, - TclGetString(resObj), -1); - } - Tcl_Release(rcPtr); - Tcl_DecrRefCount(optionObj); - break; - } - - case ForwardedGetOptAll: - /* - * Retrieve all options. - */ - - Tcl_Preserve(rcPtr); - if (InvokeTclMethod(rcPtr, "cgetall", NULL, NULL, &resObj) != TCL_OK){ - ForwardSetObjError(paramPtr, resObj); - } else { - /* - * Extract list, validate that it is a list, and #elements. See - * NOTE (4) as well. - */ - - int listc; - Tcl_Obj **listv; - - if (Tcl_ListObjGetElements(interp, resObj, &listc, - &listv) != TCL_OK) { - Tcl_DecrRefCount(resObj); - resObj = MarshallError(interp); - ForwardSetObjError(paramPtr, resObj); - } else if ((listc % 2) == 1) { - /* - * Odd number of elements is wrong. [x]. - */ - - char *buf = ckalloc(200); - sprintf(buf, - "{Expected list with even number of elements, got %d %s instead}", - listc, (listc == 1 ? "element" : "elements")); - - ForwardSetDynamicError(paramPtr, buf); - } else { - int len; - const char *str = Tcl_GetStringFromObj(resObj, &len); - - if (len) { - Tcl_DStringAppend(paramPtr->getOpt.value, " ", 1); - Tcl_DStringAppend(paramPtr->getOpt.value, str, len); - } - } - } - Tcl_Release(rcPtr); - break; - - default: - /* - * Bad operation code. - */ - - Tcl_Panic("Bad operation code in ForwardProc"); - break; - } - - /* - * Remove the reference we held on the result of the invoke, if we had - * such. - */ - - if (resObj != NULL) { - Tcl_DecrRefCount(resObj); - } - - if (resultPtr) { - /* - * Report the forwarding result synchronously to the waiting caller. - * This unblocks (*) as well. This is wrapped into a conditional - * because the caller may have exited in the mean time. - */ - - Tcl_MutexLock(&rcForwardMutex); - resultPtr->result = TCL_OK; - Tcl_ConditionNotify(&resultPtr->done); - Tcl_MutexUnlock(&rcForwardMutex); - } - - return 1; -} - -static void -SrcExitProc( - ClientData clientData) -{ - ForwardingEvent *evPtr = clientData; - ForwardingResult *resultPtr; - ForwardParam *paramPtr; - - /* - * NOTE (2): Can this handler be called with the originator blocked? - */ - - /* - * The originator for the event exited. It is not sure if this can happen, - * as the originator should be blocked at (*) while the event is in - * transit/pending. - * - * We make sure that the event cannot refer to the result anymore, remove - * it from the list of pending results and free the structure. Locking the - * access ensures that we cannot get in conflict with "ForwardProc", - * should it already execute the event. - */ - - Tcl_MutexLock(&rcForwardMutex); - - resultPtr = evPtr->resultPtr; - paramPtr = evPtr->param; - - evPtr->resultPtr = NULL; - resultPtr->evPtr = NULL; - resultPtr->result = TCL_ERROR; - - ForwardSetStaticError(paramPtr, msg_send_originlost); - - /* - * See below: TclSpliceOut(resultPtr, forwardList); - */ - - Tcl_MutexUnlock(&rcForwardMutex); - - /* - * This unlocks (*). The structure will be spliced out and freed by - * "ForwardProc". Maybe. - */ - - Tcl_ConditionNotify(&resultPtr->done); -} - -static void -ForwardSetObjError( - ForwardParam *paramPtr, - Tcl_Obj *obj) -{ - int len; - const char *msgStr = Tcl_GetStringFromObj(obj, &len); - - len++; - ForwardSetDynamicError(paramPtr, ckalloc(len)); - memcpy(paramPtr->base.msgStr, msgStr, (unsigned) len); -} -#endif - -/* - * Local Variables: - * mode: c - * c-basic-offset: 4 - * fill-column: 78 - * tab-width: 8 - * indent-tabs-mode: nil - * End: - */ |