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[/] [or1k/] [trunk/] [insight/] [tcl/] [generic/] [tclIO.c] - Rev 1765
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/* * tclIO.c -- * * This file provides the generic portions (those that are the same on * all platforms and for all channel types) of Tcl's IO facilities. * * Copyright (c) 1998 Scriptics Corporation * Copyright (c) 1995-1997 Sun Microsystems, Inc. * * See the file "license.terms" for information on usage and redistribution * of this file, and for a DISCLAIMER OF ALL WARRANTIES. * * RCS: @(#) $Id: tclIO.c,v 1.1.1.1 2002-01-16 10:25:27 markom Exp $ */ #include "tclInt.h" #include "tclPort.h" /* * Make sure that both EAGAIN and EWOULDBLOCK are defined. This does not * compile on systems where neither is defined. We want both defined so * that we can test safely for both. In the code we still have to test for * both because there may be systems on which both are defined and have * different values. */ #if ((!defined(EWOULDBLOCK)) && (defined(EAGAIN))) # define EWOULDBLOCK EAGAIN #endif #if ((!defined(EAGAIN)) && (defined(EWOULDBLOCK))) # define EAGAIN EWOULDBLOCK #endif #if ((!defined(EAGAIN)) && (!defined(EWOULDBLOCK))) error one of EWOULDBLOCK or EAGAIN must be defined #endif /* * The following structure encapsulates the state for a background channel * copy. Note that the data buffer for the copy will be appended to this * structure. */ typedef struct CopyState { struct Channel *readPtr; /* Pointer to input channel. */ struct Channel *writePtr; /* Pointer to output channel. */ int readFlags; /* Original read channel flags. */ int writeFlags; /* Original write channel flags. */ int toRead; /* Number of bytes to copy, or -1. */ int total; /* Total bytes transferred (written). */ Tcl_Interp *interp; /* Interp that started the copy. */ Tcl_Obj *cmdPtr; /* Command to be invoked at completion. */ int bufSize; /* Size of appended buffer. */ char buffer[1]; /* Copy buffer, this must be the last * field. */ } CopyState; /* * struct ChannelBuffer: * * Buffers data being sent to or from a channel. */ typedef struct ChannelBuffer { int nextAdded; /* The next position into which a character * will be put in the buffer. */ int nextRemoved; /* Position of next byte to be removed * from the buffer. */ int bufSize; /* How big is the buffer? */ struct ChannelBuffer *nextPtr; /* Next buffer in chain. */ char buf[4]; /* Placeholder for real buffer. The real * buffer occuppies this space + bufSize-4 * bytes. This must be the last field in * the structure. */ } ChannelBuffer; #define CHANNELBUFFER_HEADER_SIZE (sizeof(ChannelBuffer) - 4) /* * The following defines the *default* buffer size for channels. */ #define CHANNELBUFFER_DEFAULT_SIZE (1024 * 4) /* * Structure to record a close callback. One such record exists for * each close callback registered for a channel. */ typedef struct CloseCallback { Tcl_CloseProc *proc; /* The procedure to call. */ ClientData clientData; /* Arbitrary one-word data to pass * to the callback. */ struct CloseCallback *nextPtr; /* For chaining close callbacks. */ } CloseCallback; /* * The following structure describes the information saved from a call to * "fileevent". This is used later when the event being waited for to * invoke the saved script in the interpreter designed in this record. */ typedef struct EventScriptRecord { struct Channel *chanPtr; /* The channel for which this script is * registered. This is used only when an * error occurs during evaluation of the * script, to delete the handler. */ char *script; /* Script to invoke. */ Tcl_Interp *interp; /* In what interpreter to invoke script? */ int mask; /* Events must overlap current mask for the * stored script to be invoked. */ struct EventScriptRecord *nextPtr; /* Next in chain of records. */ } EventScriptRecord; /* * struct Channel: * * One of these structures is allocated for each open channel. It contains data * specific to the channel but which belongs to the generic part of the Tcl * channel mechanism, and it points at an instance specific (and type * specific) * instance data, and at a channel type structure. */ typedef struct Channel { char *channelName; /* The name of the channel instance in Tcl * commands. Storage is owned by the generic IO * code, is dynamically allocated. */ int flags; /* ORed combination of the flags defined * below. */ Tcl_EolTranslation inputTranslation; /* What translation to apply for end of line * sequences on input? */ Tcl_EolTranslation outputTranslation; /* What translation to use for generating * end of line sequences in output? */ int inEofChar; /* If nonzero, use this as a signal of EOF * on input. */ int outEofChar; /* If nonzero, append this to the channel * when it is closed if it is open for * writing. */ int unreportedError; /* Non-zero if an error report was deferred * because it happened in the background. The * value is the POSIX error code. */ ClientData instanceData; /* Instance specific data. */ Tcl_ChannelType *typePtr; /* Pointer to channel type structure. */ int refCount; /* How many interpreters hold references to * this IO channel? */ CloseCallback *closeCbPtr; /* Callbacks registered to be called when the * channel is closed. */ ChannelBuffer *curOutPtr; /* Current output buffer being filled. */ ChannelBuffer *outQueueHead;/* Points at first buffer in output queue. */ ChannelBuffer *outQueueTail;/* Points at last buffer in output queue. */ ChannelBuffer *saveInBufPtr;/* Buffer saved for input queue - eliminates * need to allocate a new buffer for "gets" * that crosses buffer boundaries. */ ChannelBuffer *inQueueHead; /* Points at first buffer in input queue. */ ChannelBuffer *inQueueTail; /* Points at last buffer in input queue. */ struct ChannelHandler *chPtr;/* List of channel handlers registered * for this channel. */ int interestMask; /* Mask of all events this channel has * handlers for. */ struct Channel *nextChanPtr;/* Next in list of channels currently open. */ EventScriptRecord *scriptRecordPtr; /* Chain of all scripts registered for * event handlers ("fileevent") on this * channel. */ int bufSize; /* What size buffers to allocate? */ Tcl_TimerToken timer; /* Handle to wakeup timer for this channel. */ CopyState *csPtr; /* State of background copy, or NULL. */ } Channel; /* * Values for the flags field in Channel. Any ORed combination of the * following flags can be stored in the field. These flags record various * options and state bits about the channel. In addition to the flags below, * the channel can also have TCL_READABLE (1<<1) and TCL_WRITABLE (1<<2) set. */ #define CHANNEL_NONBLOCKING (1<<3) /* Channel is currently in * nonblocking mode. */ #define CHANNEL_LINEBUFFERED (1<<4) /* Output to the channel must be * flushed after every newline. */ #define CHANNEL_UNBUFFERED (1<<5) /* Output to the channel must always * be flushed immediately. */ #define BUFFER_READY (1<<6) /* Current output buffer (the * curOutPtr field in the * channel structure) should be * output as soon as possible even * though it may not be full. */ #define BG_FLUSH_SCHEDULED (1<<7) /* A background flush of the * queued output buffers has been * scheduled. */ #define CHANNEL_CLOSED (1<<8) /* Channel has been closed. No * further Tcl-level IO on the * channel is allowed. */ #define CHANNEL_EOF (1<<9) /* EOF occurred on this channel. * This bit is cleared before every * input operation. */ #define CHANNEL_STICKY_EOF (1<<10) /* EOF occurred on this channel because * we saw the input eofChar. This bit * prevents clearing of the EOF bit * before every input operation. */ #define CHANNEL_BLOCKED (1<<11) /* EWOULDBLOCK or EAGAIN occurred * on this channel. This bit is * cleared before every input or * output operation. */ #define INPUT_SAW_CR (1<<12) /* Channel is in CRLF eol input * translation mode and the last * byte seen was a "\r". */ #define CHANNEL_DEAD (1<<13) /* The channel has been closed by * the exit handler (on exit) but * not deallocated. When any IO * operation sees this flag on a * channel, it does not call driver * level functions to avoid referring * to deallocated data. */ #define CHANNEL_GETS_BLOCKED (1<<14) /* The last input operation was a gets * that failed to get a comlete line. * When set, file events will not be * delivered for buffered data unless * an EOL is present. */ /* * For each channel handler registered in a call to Tcl_CreateChannelHandler, * there is one record of the following type. All of records for a specific * channel are chained together in a singly linked list which is stored in * the channel structure. */ typedef struct ChannelHandler { Channel *chanPtr; /* The channel structure for this channel. */ int mask; /* Mask of desired events. */ Tcl_ChannelProc *proc; /* Procedure to call in the type of * Tcl_CreateChannelHandler. */ ClientData clientData; /* Argument to pass to procedure. */ struct ChannelHandler *nextPtr; /* Next one in list of registered handlers. */ } ChannelHandler; /* * This structure keeps track of the current ChannelHandler being invoked in * the current invocation of ChannelHandlerEventProc. There is a potential * problem if a ChannelHandler is deleted while it is the current one, since * ChannelHandlerEventProc needs to look at the nextPtr field. To handle this * problem, structures of the type below indicate the next handler to be * processed for any (recursively nested) dispatches in progress. The * nextHandlerPtr field is updated if the handler being pointed to is deleted. * The nextPtr field is used to chain together all recursive invocations, so * that Tcl_DeleteChannelHandler can find all the recursively nested * invocations of ChannelHandlerEventProc and compare the handler being * deleted against the NEXT handler to be invoked in that invocation; when it * finds such a situation, Tcl_DeleteChannelHandler updates the nextHandlerPtr * field of the structure to the next handler. */ typedef struct NextChannelHandler { ChannelHandler *nextHandlerPtr; /* The next handler to be invoked in * this invocation. */ struct NextChannelHandler *nestedHandlerPtr; /* Next nested invocation of * ChannelHandlerEventProc. */ } NextChannelHandler; /* * This variable holds the list of nested ChannelHandlerEventProc invocations. */ static NextChannelHandler *nestedHandlerPtr = (NextChannelHandler *) NULL; /* * List of all channels currently open. */ static Channel *firstChanPtr = (Channel *) NULL; /* * Has a channel exit handler been created yet? */ static int channelExitHandlerCreated = 0; /* * The following structure describes the event that is added to the Tcl * event queue by the channel handler check procedure. */ typedef struct ChannelHandlerEvent { Tcl_Event header; /* Standard header for all events. */ Channel *chanPtr; /* The channel that is ready. */ int readyMask; /* Events that have occurred. */ } ChannelHandlerEvent; /* * Static variables to hold channels for stdin, stdout and stderr. */ static Tcl_Channel stdinChannel = NULL; static int stdinInitialized = 0; static Tcl_Channel stdoutChannel = NULL; static int stdoutInitialized = 0; static Tcl_Channel stderrChannel = NULL; static int stderrInitialized = 0; /* * Static functions in this file: */ static void ChannelEventScriptInvoker _ANSI_ARGS_(( ClientData clientData, int flags)); static void ChannelTimerProc _ANSI_ARGS_(( ClientData clientData)); static void CheckForStdChannelsBeingClosed _ANSI_ARGS_(( Tcl_Channel chan)); static void CleanupChannelHandlers _ANSI_ARGS_(( Tcl_Interp *interp, Channel *chanPtr)); static int CloseChannel _ANSI_ARGS_((Tcl_Interp *interp, Channel *chanPtr, int errorCode)); static void CloseChannelsOnExit _ANSI_ARGS_((ClientData data)); static int CopyAndTranslateBuffer _ANSI_ARGS_(( Channel *chanPtr, char *result, int space)); static int CopyData _ANSI_ARGS_((CopyState *csPtr, int mask)); static void CopyEventProc _ANSI_ARGS_((ClientData clientData, int mask)); static void CreateScriptRecord _ANSI_ARGS_(( Tcl_Interp *interp, Channel *chanPtr, int mask, char *script)); static void DeleteChannelTable _ANSI_ARGS_(( ClientData clientData, Tcl_Interp *interp)); static void DeleteScriptRecord _ANSI_ARGS_((Tcl_Interp *interp, Channel *chanPtr, int mask)); static void DiscardInputQueued _ANSI_ARGS_(( Channel *chanPtr, int discardSavedBuffers)); static void DiscardOutputQueued _ANSI_ARGS_(( Channel *chanPtr)); static int DoRead _ANSI_ARGS_((Channel *chanPtr, char *srcPtr, int slen)); static int DoWrite _ANSI_ARGS_((Channel *chanPtr, char *srcPtr, int slen)); static int FlushChannel _ANSI_ARGS_((Tcl_Interp *interp, Channel *chanPtr, int calledFromAsyncFlush)); static Tcl_HashTable *GetChannelTable _ANSI_ARGS_((Tcl_Interp *interp)); static int GetEOL _ANSI_ARGS_((Channel *chanPtr)); static int GetInput _ANSI_ARGS_((Channel *chanPtr)); static void RecycleBuffer _ANSI_ARGS_((Channel *chanPtr, ChannelBuffer *bufPtr, int mustDiscard)); static int ScanBufferForEOL _ANSI_ARGS_((Channel *chanPtr, ChannelBuffer *bufPtr, Tcl_EolTranslation translation, int eofChar, int *bytesToEOLPtr, int *crSeenPtr)); static int ScanInputForEOL _ANSI_ARGS_((Channel *chanPtr, int *bytesQueuedPtr)); static int SetBlockMode _ANSI_ARGS_((Tcl_Interp *interp, Channel *chanPtr, int mode)); static void StopCopy _ANSI_ARGS_((CopyState *csPtr)); static void UpdateInterest _ANSI_ARGS_((Channel *chanPtr)); static int CheckForDeadChannel _ANSI_ARGS_((Tcl_Interp *interp, Channel *chan)); /* *---------------------------------------------------------------------- * * SetBlockMode -- * * This function sets the blocking mode for a channel and updates * the state flags. * * Results: * A standard Tcl result. * * Side effects: * Modifies the blocking mode of the channel and possibly generates * an error. * *---------------------------------------------------------------------- */ static int SetBlockMode(interp, chanPtr, mode) Tcl_Interp *interp; /* Interp for error reporting. */ Channel *chanPtr; /* Channel to modify. */ int mode; /* One of TCL_MODE_BLOCKING or * TCL_MODE_NONBLOCKING. */ { int result = 0; if (chanPtr->typePtr->blockModeProc != NULL) { result = (chanPtr->typePtr->blockModeProc) (chanPtr->instanceData, mode); } if (result != 0) { Tcl_SetErrno(result); if (interp != (Tcl_Interp *) NULL) { Tcl_AppendResult(interp, "error setting blocking mode: ", Tcl_PosixError(interp), (char *) NULL); } return TCL_ERROR; } if (mode == TCL_MODE_BLOCKING) { chanPtr->flags &= (~(CHANNEL_NONBLOCKING | BG_FLUSH_SCHEDULED)); } else { chanPtr->flags |= CHANNEL_NONBLOCKING; } return TCL_OK; } /* *---------------------------------------------------------------------- * * Tcl_SetStdChannel -- * * This function is used to change the channels that are used * for stdin/stdout/stderr in new interpreters. * * Results: * None * * Side effects: * None. * *---------------------------------------------------------------------- */ void Tcl_SetStdChannel(channel, type) Tcl_Channel channel; int type; /* One of TCL_STDIN, TCL_STDOUT, TCL_STDERR. */ { switch (type) { case TCL_STDIN: stdinInitialized = 1; stdinChannel = channel; break; case TCL_STDOUT: stdoutInitialized = 1; stdoutChannel = channel; break; case TCL_STDERR: stderrInitialized = 1; stderrChannel = channel; break; } } /* *---------------------------------------------------------------------- * * Tcl_GetStdChannel -- * * Returns the specified standard channel. * * Results: * Returns the specified standard channel, or NULL. * * Side effects: * May cause the creation of a standard channel and the underlying * file. * *---------------------------------------------------------------------- */ Tcl_Channel Tcl_GetStdChannel(type) int type; /* One of TCL_STDIN, TCL_STDOUT, TCL_STDERR. */ { Tcl_Channel channel = NULL; /* * If the channels were not created yet, create them now and * store them in the static variables. Note that we need to set * stdinInitialized before calling TclGetDefaultStdChannel in order * to avoid recursive loops when TclGetDefaultStdChannel calls * Tcl_CreateChannel. */ switch (type) { case TCL_STDIN: if (!stdinInitialized) { stdinChannel = TclGetDefaultStdChannel(TCL_STDIN); stdinInitialized = 1; /* * Artificially bump the refcount to ensure that the channel * is only closed on exit. * * NOTE: Must only do this if stdinChannel is not NULL. It * can be NULL in situations where Tcl is unable to connect * to the standard input. */ if (stdinChannel != (Tcl_Channel) NULL) { (void) Tcl_RegisterChannel((Tcl_Interp *) NULL, stdinChannel); } } channel = stdinChannel; break; case TCL_STDOUT: if (!stdoutInitialized) { stdoutChannel = TclGetDefaultStdChannel(TCL_STDOUT); stdoutInitialized = 1; /* * Artificially bump the refcount to ensure that the channel * is only closed on exit. * * NOTE: Must only do this if stdoutChannel is not NULL. It * can be NULL in situations where Tcl is unable to connect * to the standard output. */ if (stdoutChannel != (Tcl_Channel) NULL) { (void) Tcl_RegisterChannel((Tcl_Interp *) NULL, stdoutChannel); } } channel = stdoutChannel; break; case TCL_STDERR: if (!stderrInitialized) { stderrChannel = TclGetDefaultStdChannel(TCL_STDERR); stderrInitialized = 1; /* * Artificially bump the refcount to ensure that the channel * is only closed on exit. * * NOTE: Must only do this if stderrChannel is not NULL. It * can be NULL in situations where Tcl is unable to connect * to the standard error. */ if (stderrChannel != (Tcl_Channel) NULL) { (void) Tcl_RegisterChannel((Tcl_Interp *) NULL, stderrChannel); } } channel = stderrChannel; break; } return channel; } /* *---------------------------------------------------------------------- * * Tcl_CreateCloseHandler * * Creates a close callback which will be called when the channel is * closed. * * Results: * None. * * Side effects: * Causes the callback to be called in the future when the channel * will be closed. * *---------------------------------------------------------------------- */ void Tcl_CreateCloseHandler(chan, proc, clientData) Tcl_Channel chan; /* The channel for which to create the * close callback. */ Tcl_CloseProc *proc; /* The callback routine to call when the * channel will be closed. */ ClientData clientData; /* Arbitrary data to pass to the * close callback. */ { Channel *chanPtr; CloseCallback *cbPtr; chanPtr = (Channel *) chan; cbPtr = (CloseCallback *) ckalloc((unsigned) sizeof(CloseCallback)); cbPtr->proc = proc; cbPtr->clientData = clientData; cbPtr->nextPtr = chanPtr->closeCbPtr; chanPtr->closeCbPtr = cbPtr; } /* *---------------------------------------------------------------------- * * Tcl_DeleteCloseHandler -- * * Removes a callback that would have been called on closing * the channel. If there is no matching callback then this * function has no effect. * * Results: * None. * * Side effects: * The callback will not be called in the future when the channel * is eventually closed. * *---------------------------------------------------------------------- */ void Tcl_DeleteCloseHandler(chan, proc, clientData) Tcl_Channel chan; /* The channel for which to cancel the * close callback. */ Tcl_CloseProc *proc; /* The procedure for the callback to * remove. */ ClientData clientData; /* The callback data for the callback * to remove. */ { Channel *chanPtr; CloseCallback *cbPtr, *cbPrevPtr; chanPtr = (Channel *) chan; for (cbPtr = chanPtr->closeCbPtr, cbPrevPtr = (CloseCallback *) NULL; cbPtr != (CloseCallback *) NULL; cbPtr = cbPtr->nextPtr) { if ((cbPtr->proc == proc) && (cbPtr->clientData == clientData)) { if (cbPrevPtr == (CloseCallback *) NULL) { chanPtr->closeCbPtr = cbPtr->nextPtr; } ckfree((char *) cbPtr); break; } else { cbPrevPtr = cbPtr; } } } /* *---------------------------------------------------------------------- * * CloseChannelsOnExit -- * * Closes all the existing channels, on exit. This routine is called * during exit processing. * * Results: * None. * * Side effects: * Closes all channels. * *---------------------------------------------------------------------- */ /* ARGSUSED */ static void CloseChannelsOnExit(clientData) ClientData clientData; /* NULL - unused. */ { Channel *chanPtr; /* Iterates over open channels. */ Channel *nextChanPtr; /* Iterates over open channels. */ for (chanPtr = firstChanPtr; chanPtr != (Channel *) NULL; chanPtr = nextChanPtr) { nextChanPtr = chanPtr->nextChanPtr; /* * Set the channel back into blocking mode to ensure that we wait * for all data to flush out. */ (void) Tcl_SetChannelOption(NULL, (Tcl_Channel) chanPtr, "-blocking", "on"); if ((chanPtr == (Channel *) stdinChannel) || (chanPtr == (Channel *) stdoutChannel) || (chanPtr == (Channel *) stderrChannel)) { /* * Decrement the refcount which was earlier artificially bumped * up to keep the channel from being closed. */ chanPtr->refCount--; } if (chanPtr->refCount <= 0) { /* * Close it only if the refcount indicates that the channel is not * referenced from any interpreter. If it is, that interpreter will * close the channel when it gets destroyed. */ (void) Tcl_Close((Tcl_Interp *) NULL, (Tcl_Channel) chanPtr); } else { /* * The refcount is greater than zero, so flush the channel. */ Tcl_Flush((Tcl_Channel) chanPtr); /* * Call the device driver to actually close the underlying * device for this channel. */ (chanPtr->typePtr->closeProc) (chanPtr->instanceData, (Tcl_Interp *) NULL); /* * Finally, we clean up the fields in the channel data structure * since all of them have been deleted already. We mark the * channel with CHANNEL_DEAD to prevent any further IO operations * on it. */ chanPtr->instanceData = (ClientData) NULL; chanPtr->flags |= CHANNEL_DEAD; } } /* * Reinitialize all the variables to the initial state: */ firstChanPtr = (Channel *) NULL; nestedHandlerPtr = (NextChannelHandler *) NULL; channelExitHandlerCreated = 0; stdinChannel = NULL; stdinInitialized = 0; stdoutChannel = NULL; stdoutInitialized = 0; stderrChannel = NULL; stderrInitialized = 0; } /* *---------------------------------------------------------------------- * * GetChannelTable -- * * Gets and potentially initializes the channel table for an * interpreter. If it is initializing the table it also inserts * channels for stdin, stdout and stderr if the interpreter is * trusted. * * Results: * A pointer to the hash table created, for use by the caller. * * Side effects: * Initializes the channel table for an interpreter. May create * channels for stdin, stdout and stderr. * *---------------------------------------------------------------------- */ static Tcl_HashTable * GetChannelTable(interp) Tcl_Interp *interp; { Tcl_HashTable *hTblPtr; /* Hash table of channels. */ Tcl_Channel stdinChan, stdoutChan, stderrChan; hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); if (hTblPtr == (Tcl_HashTable *) NULL) { hTblPtr = (Tcl_HashTable *) ckalloc((unsigned) sizeof(Tcl_HashTable)); Tcl_InitHashTable(hTblPtr, TCL_STRING_KEYS); (void) Tcl_SetAssocData(interp, "tclIO", (Tcl_InterpDeleteProc *) DeleteChannelTable, (ClientData) hTblPtr); /* * If the interpreter is trusted (not "safe"), insert channels * for stdin, stdout and stderr (possibly creating them in the * process). */ if (Tcl_IsSafe(interp) == 0) { stdinChan = Tcl_GetStdChannel(TCL_STDIN); if (stdinChan != NULL) { Tcl_RegisterChannel(interp, stdinChan); } stdoutChan = Tcl_GetStdChannel(TCL_STDOUT); if (stdoutChan != NULL) { Tcl_RegisterChannel(interp, stdoutChan); } stderrChan = Tcl_GetStdChannel(TCL_STDERR); if (stderrChan != NULL) { Tcl_RegisterChannel(interp, stderrChan); } } } return hTblPtr; } /* *---------------------------------------------------------------------- * * DeleteChannelTable -- * * Deletes the channel table for an interpreter, closing any open * channels whose refcount reaches zero. This procedure is invoked * when an interpreter is deleted, via the AssocData cleanup * mechanism. * * Results: * None. * * Side effects: * Deletes the hash table of channels. May close channels. May flush * output on closed channels. Removes any channeEvent handlers that were * registered in this interpreter. * *---------------------------------------------------------------------- */ static void DeleteChannelTable(clientData, interp) ClientData clientData; /* The per-interpreter data structure. */ Tcl_Interp *interp; /* The interpreter being deleted. */ { Tcl_HashTable *hTblPtr; /* The hash table. */ Tcl_HashSearch hSearch; /* Search variable. */ Tcl_HashEntry *hPtr; /* Search variable. */ Channel *chanPtr; /* Channel being deleted. */ EventScriptRecord *sPtr, *prevPtr, *nextPtr; /* Variables to loop over all channel events * registered, to delete the ones that refer * to the interpreter being deleted. */ /* * Delete all the registered channels - this will close channels whose * refcount reaches zero. */ hTblPtr = (Tcl_HashTable *) clientData; for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); hPtr != (Tcl_HashEntry *) NULL; hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch)) { chanPtr = (Channel *) Tcl_GetHashValue(hPtr); /* * Remove any fileevents registered in this interpreter. */ for (sPtr = chanPtr->scriptRecordPtr, prevPtr = (EventScriptRecord *) NULL; sPtr != (EventScriptRecord *) NULL; sPtr = nextPtr) { nextPtr = sPtr->nextPtr; if (sPtr->interp == interp) { if (prevPtr == (EventScriptRecord *) NULL) { chanPtr->scriptRecordPtr = nextPtr; } else { prevPtr->nextPtr = nextPtr; } Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, ChannelEventScriptInvoker, (ClientData) sPtr); ckfree(sPtr->script); ckfree((char *) sPtr); } else { prevPtr = sPtr; } } /* * Cannot call Tcl_UnregisterChannel because that procedure calls * Tcl_GetAssocData to get the channel table, which might already * be inaccessible from the interpreter structure. Instead, we * emulate the behavior of Tcl_UnregisterChannel directly here. */ Tcl_DeleteHashEntry(hPtr); chanPtr->refCount--; if (chanPtr->refCount <= 0) { if (!(chanPtr->flags & BG_FLUSH_SCHEDULED)) { (void) Tcl_Close(interp, (Tcl_Channel) chanPtr); } } } Tcl_DeleteHashTable(hTblPtr); ckfree((char *) hTblPtr); } /* *---------------------------------------------------------------------- * * CheckForStdChannelsBeingClosed -- * * Perform special handling for standard channels being closed. When * given a standard channel, if the refcount is now 1, it means that * the last reference to the standard channel is being explicitly * closed. Now bump the refcount artificially down to 0, to ensure the * normal handling of channels being closed will occur. Also reset the * static pointer to the channel to NULL, to avoid dangling references. * * Results: * None. * * Side effects: * Manipulates the refcount on standard channels. May smash the global * static pointer to a standard channel. * *---------------------------------------------------------------------- */ static void CheckForStdChannelsBeingClosed(chan) Tcl_Channel chan; { Channel *chanPtr = (Channel *) chan; if ((chan == stdinChannel) && (stdinInitialized)) { if (chanPtr->refCount < 2) { chanPtr->refCount = 0; stdinChannel = NULL; return; } } else if ((chan == stdoutChannel) && (stdoutInitialized)) { if (chanPtr->refCount < 2) { chanPtr->refCount = 0; stdoutChannel = NULL; return; } } else if ((chan == stderrChannel) && (stderrInitialized)) { if (chanPtr->refCount < 2) { chanPtr->refCount = 0; stderrChannel = NULL; return; } } } /* *---------------------------------------------------------------------- * * Tcl_UnregisterChannel -- * * Deletes the hash entry for a channel associated with an interpreter. * If the interpreter given as argument is NULL, it only decrements the * reference count. * * Results: * A standard Tcl result. * * Side effects: * Deletes the hash entry for a channel associated with an interpreter. * *---------------------------------------------------------------------- */ int Tcl_UnregisterChannel(interp, chan) Tcl_Interp *interp; /* Interpreter in which channel is defined. */ Tcl_Channel chan; /* Channel to delete. */ { Tcl_HashTable *hTblPtr; /* Hash table of channels. */ Tcl_HashEntry *hPtr; /* Search variable. */ Channel *chanPtr; /* The real IO channel. */ chanPtr = (Channel *) chan; if (interp != (Tcl_Interp *) NULL) { hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); if (hTblPtr == (Tcl_HashTable *) NULL) { return TCL_OK; } hPtr = Tcl_FindHashEntry(hTblPtr, chanPtr->channelName); if (hPtr == (Tcl_HashEntry *) NULL) { return TCL_OK; } if ((Channel *) Tcl_GetHashValue(hPtr) != chanPtr) { return TCL_OK; } Tcl_DeleteHashEntry(hPtr); /* * Remove channel handlers that refer to this interpreter, so that they * will not be present if the actual close is delayed and more events * happen on the channel. This may occur if the channel is shared * between several interpreters, or if the channel has async * flushing active. */ CleanupChannelHandlers(interp, chanPtr); } chanPtr->refCount--; /* * Perform special handling for standard channels being closed. If the * refCount is now 1 it means that the last reference to the standard * channel is being explicitly closed, so bump the refCount down * artificially to 0. This will ensure that the channel is actually * closed, below. Also set the static pointer to NULL for the channel. */ CheckForStdChannelsBeingClosed(chan); /* * If the refCount reached zero, close the actual channel. */ if (chanPtr->refCount <= 0) { /* * Ensure that if there is another buffer, it gets flushed * whether or not we are doing a background flush. */ if ((chanPtr->curOutPtr != NULL) && (chanPtr->curOutPtr->nextAdded > chanPtr->curOutPtr->nextRemoved)) { chanPtr->flags |= BUFFER_READY; } chanPtr->flags |= CHANNEL_CLOSED; if (!(chanPtr->flags & BG_FLUSH_SCHEDULED)) { if (Tcl_Close(interp, chan) != TCL_OK) { return TCL_ERROR; } } } return TCL_OK; } /* *---------------------------------------------------------------------- * * Tcl_RegisterChannel -- * * Adds an already-open channel to the channel table of an interpreter. * If the interpreter passed as argument is NULL, it only increments * the channel refCount. * * Results: * None. * * Side effects: * May increment the reference count of a channel. * *---------------------------------------------------------------------- */ void Tcl_RegisterChannel(interp, chan) Tcl_Interp *interp; /* Interpreter in which to add the channel. */ Tcl_Channel chan; /* The channel to add to this interpreter * channel table. */ { Tcl_HashTable *hTblPtr; /* Hash table of channels. */ Tcl_HashEntry *hPtr; /* Search variable. */ int new; /* Is the hash entry new or does it exist? */ Channel *chanPtr; /* The actual channel. */ chanPtr = (Channel *) chan; if (chanPtr->channelName == (char *) NULL) { panic("Tcl_RegisterChannel: channel without name"); } if (interp != (Tcl_Interp *) NULL) { hTblPtr = GetChannelTable(interp); hPtr = Tcl_CreateHashEntry(hTblPtr, chanPtr->channelName, &new); if (new == 0) { if (chan == (Tcl_Channel) Tcl_GetHashValue(hPtr)) { return; } panic("Tcl_RegisterChannel: duplicate channel names"); } Tcl_SetHashValue(hPtr, (ClientData) chanPtr); } chanPtr->refCount++; } /* *---------------------------------------------------------------------- * * Tcl_GetChannel -- * * Finds an existing Tcl_Channel structure by name in a given * interpreter. This function is public because it is used by * channel-type-specific functions. * * Results: * A Tcl_Channel or NULL on failure. If failed, interp->result * contains an error message. It also returns, in modePtr, the * modes in which the channel is opened. * * Side effects: * None. * *---------------------------------------------------------------------- */ Tcl_Channel Tcl_GetChannel(interp, chanName, modePtr) Tcl_Interp *interp; /* Interpreter in which to find or create * the channel. */ char *chanName; /* The name of the channel. */ int *modePtr; /* Where to store the mode in which the * channel was opened? Will contain an ORed * combination of TCL_READABLE and * TCL_WRITABLE, if non-NULL. */ { Channel *chanPtr; /* The actual channel. */ Tcl_HashTable *hTblPtr; /* Hash table of channels. */ Tcl_HashEntry *hPtr; /* Search variable. */ char *name; /* Translated name. */ /* * Substitute "stdin", etc. Note that even though we immediately * find the channel using Tcl_GetStdChannel, we still need to look * it up in the specified interpreter to ensure that it is present * in the channel table. Otherwise, safe interpreters would always * have access to the standard channels. */ name = chanName; if ((chanName[0] == 's') && (chanName[1] == 't')) { chanPtr = NULL; if (strcmp(chanName, "stdin") == 0) { chanPtr = (Channel *)Tcl_GetStdChannel(TCL_STDIN); } else if (strcmp(chanName, "stdout") == 0) { chanPtr = (Channel *)Tcl_GetStdChannel(TCL_STDOUT); } else if (strcmp(chanName, "stderr") == 0) { chanPtr = (Channel *)Tcl_GetStdChannel(TCL_STDERR); } if (chanPtr != NULL) { name = chanPtr->channelName; } } hTblPtr = GetChannelTable(interp); hPtr = Tcl_FindHashEntry(hTblPtr, name); if (hPtr == (Tcl_HashEntry *) NULL) { Tcl_AppendResult(interp, "can not find channel named \"", chanName, "\"", (char *) NULL); return NULL; } chanPtr = (Channel *) Tcl_GetHashValue(hPtr); if (modePtr != NULL) { *modePtr = (chanPtr->flags & (TCL_READABLE|TCL_WRITABLE)); } return (Tcl_Channel) chanPtr; } /* *---------------------------------------------------------------------- * * Tcl_CreateChannel -- * * Creates a new entry in the hash table for a Tcl_Channel * record. * * Results: * Returns the new Tcl_Channel. * * Side effects: * Creates a new Tcl_Channel instance and inserts it into the * hash table. * *---------------------------------------------------------------------- */ Tcl_Channel Tcl_CreateChannel(typePtr, chanName, instanceData, mask) Tcl_ChannelType *typePtr; /* The channel type record. */ char *chanName; /* Name of channel to record. */ ClientData instanceData; /* Instance specific data. */ int mask; /* TCL_READABLE & TCL_WRITABLE to indicate * if the channel is readable, writable. */ { Channel *chanPtr; /* The channel structure newly created. */ chanPtr = (Channel *) ckalloc((unsigned) sizeof(Channel)); if (chanName != (char *) NULL) { chanPtr->channelName = ckalloc((unsigned) (strlen(chanName) + 1)); strcpy(chanPtr->channelName, chanName); } else { panic("Tcl_CreateChannel: NULL channel name"); } chanPtr->flags = mask; /* * Set the channel up initially in AUTO input translation mode to * accept "\n", "\r" and "\r\n". Output translation mode is set to * a platform specific default value. The eofChar is set to 0 for both * input and output, so that Tcl does not look for an in-file EOF * indicator (e.g. ^Z) and does not append an EOF indicator to files. */ chanPtr->inputTranslation = TCL_TRANSLATE_AUTO; chanPtr->outputTranslation = TCL_PLATFORM_TRANSLATION; chanPtr->inEofChar = 0; chanPtr->outEofChar = 0; chanPtr->unreportedError = 0; chanPtr->instanceData = instanceData; chanPtr->typePtr = typePtr; chanPtr->refCount = 0; chanPtr->closeCbPtr = (CloseCallback *) NULL; chanPtr->curOutPtr = (ChannelBuffer *) NULL; chanPtr->outQueueHead = (ChannelBuffer *) NULL; chanPtr->outQueueTail = (ChannelBuffer *) NULL; chanPtr->saveInBufPtr = (ChannelBuffer *) NULL; chanPtr->inQueueHead = (ChannelBuffer *) NULL; chanPtr->inQueueTail = (ChannelBuffer *) NULL; chanPtr->chPtr = (ChannelHandler *) NULL; chanPtr->interestMask = 0; chanPtr->scriptRecordPtr = (EventScriptRecord *) NULL; chanPtr->bufSize = CHANNELBUFFER_DEFAULT_SIZE; chanPtr->timer = NULL; chanPtr->csPtr = NULL; /* * Link the channel into the list of all channels; create an on-exit * handler if there is not one already, to close off all the channels * in the list on exit. */ chanPtr->nextChanPtr = firstChanPtr; firstChanPtr = chanPtr; if (!channelExitHandlerCreated) { channelExitHandlerCreated = 1; Tcl_CreateExitHandler(CloseChannelsOnExit, (ClientData) NULL); } /* * Install this channel in the first empty standard channel slot, if * the channel was previously closed explicitly. */ if ((stdinChannel == NULL) && (stdinInitialized == 1)) { Tcl_SetStdChannel((Tcl_Channel)chanPtr, TCL_STDIN); Tcl_RegisterChannel((Tcl_Interp *) NULL, (Tcl_Channel) chanPtr); } else if ((stdoutChannel == NULL) && (stdoutInitialized == 1)) { Tcl_SetStdChannel((Tcl_Channel)chanPtr, TCL_STDOUT); Tcl_RegisterChannel((Tcl_Interp *) NULL, (Tcl_Channel) chanPtr); } else if ((stderrChannel == NULL) && (stderrInitialized == 1)) { Tcl_SetStdChannel((Tcl_Channel)chanPtr, TCL_STDERR); Tcl_RegisterChannel((Tcl_Interp *) NULL, (Tcl_Channel) chanPtr); } return (Tcl_Channel) chanPtr; } /* *---------------------------------------------------------------------- * * Tcl_GetChannelMode -- * * Computes a mask indicating whether the channel is open for * reading and writing. * * Results: * An OR-ed combination of TCL_READABLE and TCL_WRITABLE. * * Side effects: * None. * *---------------------------------------------------------------------- */ int Tcl_GetChannelMode(chan) Tcl_Channel chan; /* The channel for which the mode is * being computed. */ { Channel *chanPtr; /* The actual channel. */ chanPtr = (Channel *) chan; return (chanPtr->flags & (TCL_READABLE | TCL_WRITABLE)); } /* *---------------------------------------------------------------------- * * Tcl_GetChannelName -- * * Returns the string identifying the channel name. * * Results: * The string containing the channel name. This memory is * owned by the generic layer and should not be modified by * the caller. * * Side effects: * None. * *---------------------------------------------------------------------- */ char * Tcl_GetChannelName(chan) Tcl_Channel chan; /* The channel for which to return the name. */ { Channel *chanPtr; /* The actual channel. */ chanPtr = (Channel *) chan; return chanPtr->channelName; } /* *---------------------------------------------------------------------- * * Tcl_GetChannelType -- * * Given a channel structure, returns the channel type structure. * * Results: * Returns a pointer to the channel type structure. * * Side effects: * None. * *---------------------------------------------------------------------- */ Tcl_ChannelType * Tcl_GetChannelType(chan) Tcl_Channel chan; /* The channel to return type for. */ { Channel *chanPtr; /* The actual channel. */ chanPtr = (Channel *) chan; return chanPtr->typePtr; } /* *---------------------------------------------------------------------- * * Tcl_GetChannelHandle -- * * Returns an OS handle associated with a channel. * * Results: * Returns TCL_OK and places the handle in handlePtr, or returns * TCL_ERROR on failure. * * Side effects: * None. * *---------------------------------------------------------------------- */ int Tcl_GetChannelHandle(chan, direction, handlePtr) Tcl_Channel chan; /* The channel to get file from. */ int direction; /* TCL_WRITABLE or TCL_READABLE. */ ClientData *handlePtr; /* Where to store handle */ { Channel *chanPtr; /* The actual channel. */ ClientData handle; int result; chanPtr = (Channel *) chan; result = (chanPtr->typePtr->getHandleProc)(chanPtr->instanceData, direction, &handle); if (handlePtr) { *handlePtr = handle; } return result; } /* *---------------------------------------------------------------------- * * Tcl_GetChannelInstanceData -- * * Returns the client data associated with a channel. * * Results: * The client data. * * Side effects: * None. * *---------------------------------------------------------------------- */ ClientData Tcl_GetChannelInstanceData(chan) Tcl_Channel chan; /* Channel for which to return client data. */ { Channel *chanPtr; /* The actual channel. */ chanPtr = (Channel *) chan; return chanPtr->instanceData; } /* *---------------------------------------------------------------------- * * RecycleBuffer -- * * Helper function to recycle input and output buffers. Ensures * that two input buffers are saved (one in the input queue and * another in the saveInBufPtr field) and that curOutPtr is set * to a buffer. Only if these conditions are met is the buffer * freed to the OS. * * Results: * None. * * Side effects: * May free a buffer to the OS. * *---------------------------------------------------------------------- */ static void RecycleBuffer(chanPtr, bufPtr, mustDiscard) Channel *chanPtr; /* Channel for which to recycle buffers. */ ChannelBuffer *bufPtr; /* The buffer to recycle. */ int mustDiscard; /* If nonzero, free the buffer to the * OS, always. */ { /* * Do we have to free the buffer to the OS? */ if (mustDiscard) { ckfree((char *) bufPtr); return; } /* * Only save buffers for the input queue if the channel is readable. */ if (chanPtr->flags & TCL_READABLE) { if (chanPtr->inQueueHead == (ChannelBuffer *) NULL) { chanPtr->inQueueHead = bufPtr; chanPtr->inQueueTail = bufPtr; goto keepit; } if (chanPtr->saveInBufPtr == (ChannelBuffer *) NULL) { chanPtr->saveInBufPtr = bufPtr; goto keepit; } } /* * Only save buffers for the output queue if the channel is writable. */ if (chanPtr->flags & TCL_WRITABLE) { if (chanPtr->curOutPtr == (ChannelBuffer *) NULL) { chanPtr->curOutPtr = bufPtr; goto keepit; } } /* * If we reached this code we return the buffer to the OS. */ ckfree((char *) bufPtr); return; keepit: bufPtr->nextRemoved = 0; bufPtr->nextAdded = 0; bufPtr->nextPtr = (ChannelBuffer *) NULL; } /* *---------------------------------------------------------------------- * * DiscardOutputQueued -- * * Discards all output queued in the output queue of a channel. * * Results: * None. * * Side effects: * Recycles buffers. * *---------------------------------------------------------------------- */ static void DiscardOutputQueued(chanPtr) Channel *chanPtr; /* The channel for which to discard output. */ { ChannelBuffer *bufPtr; while (chanPtr->outQueueHead != (ChannelBuffer *) NULL) { bufPtr = chanPtr->outQueueHead; chanPtr->outQueueHead = bufPtr->nextPtr; RecycleBuffer(chanPtr, bufPtr, 0); } chanPtr->outQueueHead = (ChannelBuffer *) NULL; chanPtr->outQueueTail = (ChannelBuffer *) NULL; } /* *---------------------------------------------------------------------- * * CheckForDeadChannel -- * * This function checks is a given channel is Dead. * (A channel that has been closed but not yet deallocated.) * * Results: * True (1) if channel is Dead, False (0) if channel is Ok * * Side effects: * None * *---------------------------------------------------------------------- */ static int CheckForDeadChannel(interp, chanPtr) Tcl_Interp *interp; /* For error reporting (can be NULL) */ Channel *chanPtr; /* The channel to check. */ { if (chanPtr->flags & CHANNEL_DEAD) { Tcl_SetErrno(EINVAL); if (interp) { Tcl_AppendResult(interp, "unable to access channel: invalid channel", (char *) NULL); } return 1; } return 0; } /* *---------------------------------------------------------------------- * * FlushChannel -- * * This function flushes as much of the queued output as is possible * now. If calledFromAsyncFlush is nonzero, it is being called in an * event handler to flush channel output asynchronously. * * Results: * 0 if successful, else the error code that was returned by the * channel type operation. * * Side effects: * May produce output on a channel. May block indefinitely if the * channel is synchronous. May schedule an async flush on the channel. * May recycle memory for buffers in the output queue. * *---------------------------------------------------------------------- */ static int FlushChannel(interp, chanPtr, calledFromAsyncFlush) Tcl_Interp *interp; /* For error reporting during close. */ Channel *chanPtr; /* The channel to flush on. */ int calledFromAsyncFlush; /* If nonzero then we are being * called from an asynchronous * flush callback. */ { ChannelBuffer *bufPtr; /* Iterates over buffered output * queue. */ int toWrite; /* Amount of output data in current * buffer available to be written. */ int written; /* Amount of output data actually * written in current round. */ int errorCode; /* Stores POSIX error codes from * channel driver operations. */ errorCode = 0; /* * Prevent writing on a dead channel -- a channel that has been closed * but not yet deallocated. This can occur if the exit handler for the * channel deallocation runs before all channels are deregistered in * all interpreters. */ if (CheckForDeadChannel(interp,chanPtr)) return -1; /* * Loop over the queued buffers and attempt to flush as * much as possible of the queued output to the channel. */ while (1) { /* * If the queue is empty and there is a ready current buffer, OR if * the current buffer is full, then move the current buffer to the * queue. */ if (((chanPtr->curOutPtr != (ChannelBuffer *) NULL) && (chanPtr->curOutPtr->nextAdded == chanPtr->curOutPtr->bufSize)) || ((chanPtr->flags & BUFFER_READY) && (chanPtr->outQueueHead == (ChannelBuffer *) NULL))) { chanPtr->flags &= (~(BUFFER_READY)); chanPtr->curOutPtr->nextPtr = (ChannelBuffer *) NULL; if (chanPtr->outQueueHead == (ChannelBuffer *) NULL) { chanPtr->outQueueHead = chanPtr->curOutPtr; } else { chanPtr->outQueueTail->nextPtr = chanPtr->curOutPtr; } chanPtr->outQueueTail = chanPtr->curOutPtr; chanPtr->curOutPtr = (ChannelBuffer *) NULL; } bufPtr = chanPtr->outQueueHead; /* * If we are not being called from an async flush and an async * flush is active, we just return without producing any output. */ if ((!calledFromAsyncFlush) && (chanPtr->flags & BG_FLUSH_SCHEDULED)) { return 0; } /* * If the output queue is still empty, break out of the while loop. */ if (bufPtr == (ChannelBuffer *) NULL) { break; /* Out of the "while (1)". */ } /* * Produce the output on the channel. */ toWrite = bufPtr->nextAdded - bufPtr->nextRemoved; written = (chanPtr->typePtr->outputProc) (chanPtr->instanceData, bufPtr->buf + bufPtr->nextRemoved, toWrite, &errorCode); /* * If the write failed completely attempt to start the asynchronous * flush mechanism and break out of this loop - do not attempt to * write any more output at this time. */ if (written < 0) { /* * If the last attempt to write was interrupted, simply retry. */ if (errorCode == EINTR) { errorCode = 0; continue; } /* * If the channel is non-blocking and we would have blocked, * start a background flushing handler and break out of the loop. */ if ((errorCode == EWOULDBLOCK) || (errorCode == EAGAIN)) { if (chanPtr->flags & CHANNEL_NONBLOCKING) { if (!(chanPtr->flags & BG_FLUSH_SCHEDULED)) { chanPtr->flags |= BG_FLUSH_SCHEDULED; UpdateInterest(chanPtr); } errorCode = 0; break; } else { panic("Blocking channel driver did not block on output"); } } /* * Decide whether to report the error upwards or defer it. */ if (calledFromAsyncFlush) { if (chanPtr->unreportedError == 0) { chanPtr->unreportedError = errorCode; } } else { Tcl_SetErrno(errorCode); if (interp != NULL) { Tcl_SetResult(interp, Tcl_PosixError(interp), TCL_VOLATILE); } } /* * When we get an error we throw away all the output * currently queued. */ DiscardOutputQueued(chanPtr); continue; } bufPtr->nextRemoved += written; /* * If this buffer is now empty, recycle it. */ if (bufPtr->nextRemoved == bufPtr->nextAdded) { chanPtr->outQueueHead = bufPtr->nextPtr; if (chanPtr->outQueueHead == (ChannelBuffer *) NULL) { chanPtr->outQueueTail = (ChannelBuffer *) NULL; } RecycleBuffer(chanPtr, bufPtr, 0); } } /* Closes "while (1)". */ /* * If the queue became empty and we have the asynchronous flushing * mechanism active, cancel the asynchronous flushing. */ if ((chanPtr->outQueueHead == (ChannelBuffer *) NULL) && (chanPtr->flags & BG_FLUSH_SCHEDULED)) { chanPtr->flags &= (~(BG_FLUSH_SCHEDULED)); (chanPtr->typePtr->watchProc)(chanPtr->instanceData, chanPtr->interestMask); } /* * If the channel is flagged as closed, delete it when the refCount * drops to zero, the output queue is empty and there is no output * in the current output buffer. */ if ((chanPtr->flags & CHANNEL_CLOSED) && (chanPtr->refCount <= 0) && (chanPtr->outQueueHead == (ChannelBuffer *) NULL) && ((chanPtr->curOutPtr == (ChannelBuffer *) NULL) || (chanPtr->curOutPtr->nextAdded == chanPtr->curOutPtr->nextRemoved))) { return CloseChannel(interp, chanPtr, errorCode); } return errorCode; } /* *---------------------------------------------------------------------- * * CloseChannel -- * * Utility procedure to close a channel and free its associated * resources. * * Results: * 0 on success or a POSIX error code if the operation failed. * * Side effects: * May close the actual channel; may free memory. * *---------------------------------------------------------------------- */ static int CloseChannel(interp, chanPtr, errorCode) Tcl_Interp *interp; /* For error reporting. */ Channel *chanPtr; /* The channel to close. */ int errorCode; /* Status of operation so far. */ { int result = 0; /* Of calling driver close * operation. */ Channel *prevChanPtr; /* Preceding channel in list of * all channels - used to splice a * channel out of the list on close. */ if (chanPtr == NULL) { return result; } /* * No more input can be consumed so discard any leftover input. */ DiscardInputQueued(chanPtr, 1); /* * Discard a leftover buffer in the current output buffer field. */ if (chanPtr->curOutPtr != (ChannelBuffer *) NULL) { ckfree((char *) chanPtr->curOutPtr); chanPtr->curOutPtr = (ChannelBuffer *) NULL; } /* * The caller guarantees that there are no more buffers * queued for output. */ if (chanPtr->outQueueHead != (ChannelBuffer *) NULL) { panic("TclFlush, closed channel: queued output left"); } /* * If the EOF character is set in the channel, append that to the * output device. */ if ((chanPtr->outEofChar != 0) && (chanPtr->flags & TCL_WRITABLE)) { int dummy; char c; c = (char) chanPtr->outEofChar; (chanPtr->typePtr->outputProc) (chanPtr->instanceData, &c, 1, &dummy); } /* * Remove TCL_READABLE and TCL_WRITABLE from chanPtr->flags, so * that close callbacks can not do input or output (assuming they * squirreled the channel away in their clientData). This also * prevents infinite loops if the callback calls any C API that * could call FlushChannel. */ chanPtr->flags &= (~(TCL_READABLE|TCL_WRITABLE)); /* * Splice this channel out of the list of all channels. */ if (chanPtr == firstChanPtr) { firstChanPtr = chanPtr->nextChanPtr; } else { for (prevChanPtr = firstChanPtr; (prevChanPtr != (Channel *) NULL) && (prevChanPtr->nextChanPtr != chanPtr); prevChanPtr = prevChanPtr->nextChanPtr) { /* Empty loop body. */ } if (prevChanPtr == (Channel *) NULL) { panic("FlushChannel: damaged channel list"); } prevChanPtr->nextChanPtr = chanPtr->nextChanPtr; } /* * OK, close the channel itself. */ result = (chanPtr->typePtr->closeProc) (chanPtr->instanceData, interp); if (chanPtr->channelName != (char *) NULL) { ckfree(chanPtr->channelName); } /* * If we are being called synchronously, report either * any latent error on the channel or the current error. */ if (chanPtr->unreportedError != 0) { errorCode = chanPtr->unreportedError; } if (errorCode == 0) { errorCode = result; if (errorCode != 0) { Tcl_SetErrno(errorCode); } } /* * Cancel any outstanding timer. */ Tcl_DeleteTimerHandler(chanPtr->timer); /* * Mark the channel as deleted by clearing the type structure. */ chanPtr->typePtr = NULL; Tcl_EventuallyFree((ClientData) chanPtr, TCL_DYNAMIC); return errorCode; } /* *---------------------------------------------------------------------- * * Tcl_Close -- * * Closes a channel. * * Results: * A standard Tcl result. * * Side effects: * Closes the channel if this is the last reference. * * NOTE: * Tcl_Close removes the channel as far as the user is concerned. * However, it may continue to exist for a while longer if it has * a background flush scheduled. The device itself is eventually * closed and the channel record removed, in CloseChannel, above. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int Tcl_Close(interp, chan) Tcl_Interp *interp; /* Interpreter for errors. */ Tcl_Channel chan; /* The channel being closed. Must * not be referenced in any * interpreter. */ { ChannelHandler *chPtr, *chNext; /* Iterate over channel handlers. */ CloseCallback *cbPtr; /* Iterate over close callbacks * for this channel. */ EventScriptRecord *ePtr, *eNextPtr; /* Iterate over eventscript records. */ Channel *chanPtr; /* The real IO channel. */ int result; /* Of calling FlushChannel. */ NextChannelHandler *nhPtr; if (chan == (Tcl_Channel) NULL) { return TCL_OK; } /* * Perform special handling for standard channels being closed. If the * refCount is now 1 it means that the last reference to the standard * channel is being explicitly closed, so bump the refCount down * artificially to 0. This will ensure that the channel is actually * closed, below. Also set the static pointer to NULL for the channel. */ CheckForStdChannelsBeingClosed(chan); chanPtr = (Channel *) chan; if (chanPtr->refCount > 0) { panic("called Tcl_Close on channel with refCount > 0"); } /* * Remove any references to channel handlers for this channel that * may be about to be invoked. */ for (nhPtr = nestedHandlerPtr; nhPtr != (NextChannelHandler *) NULL; nhPtr = nhPtr->nestedHandlerPtr) { if (nhPtr->nextHandlerPtr && (nhPtr->nextHandlerPtr->chanPtr == chanPtr)) { nhPtr->nextHandlerPtr = NULL; } } /* * Remove all the channel handler records attached to the channel * itself. */ for (chPtr = chanPtr->chPtr; chPtr != (ChannelHandler *) NULL; chPtr = chNext) { chNext = chPtr->nextPtr; ckfree((char *) chPtr); } chanPtr->chPtr = (ChannelHandler *) NULL; /* * Cancel any pending copy operation. */ StopCopy(chanPtr->csPtr); /* * Must set the interest mask now to 0, otherwise infinite loops * will occur if Tcl_DoOneEvent is called before the channel is * finally deleted in FlushChannel. This can happen if the channel * has a background flush active. */ chanPtr->interestMask = 0; /* * Remove any EventScript records for this channel. */ for (ePtr = chanPtr->scriptRecordPtr; ePtr != (EventScriptRecord *) NULL; ePtr = eNextPtr) { eNextPtr = ePtr->nextPtr; ckfree(ePtr->script); ckfree((char *) ePtr); } chanPtr->scriptRecordPtr = (EventScriptRecord *) NULL; /* * Invoke the registered close callbacks and delete their records. */ while (chanPtr->closeCbPtr != (CloseCallback *) NULL) { cbPtr = chanPtr->closeCbPtr; chanPtr->closeCbPtr = cbPtr->nextPtr; (cbPtr->proc) (cbPtr->clientData); ckfree((char *) cbPtr); } /* * Ensure that the last output buffer will be flushed. */ if ((chanPtr->curOutPtr != (ChannelBuffer *) NULL) && (chanPtr->curOutPtr->nextAdded > chanPtr->curOutPtr->nextRemoved)) { chanPtr->flags |= BUFFER_READY; } /* * The call to FlushChannel will flush any queued output and invoke * the close function of the channel driver, or it will set up the * channel to be flushed and closed asynchronously. */ chanPtr->flags |= CHANNEL_CLOSED; result = FlushChannel(interp, chanPtr, 0); if (result != 0) { return TCL_ERROR; } return TCL_OK; } /* *---------------------------------------------------------------------- * * Tcl_Write -- * * Puts a sequence of characters into an output buffer, may queue the * buffer for output if it gets full, and also remembers whether the * current buffer is ready e.g. if it contains a newline and we are in * line buffering mode. * * Results: * The number of bytes written or -1 in case of error. If -1, * Tcl_GetErrno will return the error code. * * Side effects: * May buffer up output and may cause output to be produced on the * channel. * *---------------------------------------------------------------------- */ int Tcl_Write(chan, srcPtr, slen) Tcl_Channel chan; /* The channel to buffer output for. */ char *srcPtr; /* Output to buffer. */ int slen; /* Its length. Negative means * the output is null terminated * and we must compute its length. */ { Channel *chanPtr = (Channel *) chan; /* * Check for unreported error. */ if (chanPtr->unreportedError != 0) { Tcl_SetErrno(chanPtr->unreportedError); chanPtr->unreportedError = 0; return -1; } /* * If the channel is not open for writing punt. */ if (!(chanPtr->flags & TCL_WRITABLE)) { Tcl_SetErrno(EACCES); return -1; } /* * If the channel is in the middle of a background copy, fail. */ if (chanPtr->csPtr) { Tcl_SetErrno(EBUSY); return -1; } /* * If length passed is negative, assume that the output is null terminated * and compute its length. */ if (slen < 0) { slen = strlen(srcPtr); } return DoWrite(chanPtr, srcPtr, slen); } /* *---------------------------------------------------------------------- * * DoWrite -- * * Puts a sequence of characters into an output buffer, may queue the * buffer for output if it gets full, and also remembers whether the * current buffer is ready e.g. if it contains a newline and we are in * line buffering mode. * * Results: * The number of bytes written or -1 in case of error. If -1, * Tcl_GetErrno will return the error code. * * Side effects: * May buffer up output and may cause output to be produced on the * channel. * *---------------------------------------------------------------------- */ static int DoWrite(chanPtr, srcPtr, slen) Channel *chanPtr; /* The channel to buffer output for. */ char *srcPtr; /* Data to write. */ int slen; /* Number of bytes to write. */ { ChannelBuffer *outBufPtr; /* Current output buffer. */ int foundNewline; /* Did we find a newline in output? */ char *dPtr, *sPtr; /* Search variables for newline. */ int crsent; /* In CRLF eol translation mode, * remember the fact that a CR was * output to the channel without * its following NL. */ int i; /* Loop index for newline search. */ int destCopied; /* How many bytes were used in this * destination buffer to hold the * output? */ int totalDestCopied; /* How many bytes total were * copied to the channel buffer? */ int srcCopied; /* How many bytes were copied from * the source string? */ char *destPtr; /* Where in line to copy to? */ /* * If we are in network (or windows) translation mode, record the fact * that we have not yet sent a CR to the channel. */ crsent = 0; /* * Loop filling buffers and flushing them until all output has been * consumed. */ srcCopied = 0; totalDestCopied = 0; while (slen > 0) { /* * Make sure there is a current output buffer to accept output. */ if (chanPtr->curOutPtr == (ChannelBuffer *) NULL) { chanPtr->curOutPtr = (ChannelBuffer *) ckalloc((unsigned) (CHANNELBUFFER_HEADER_SIZE + chanPtr->bufSize)); chanPtr->curOutPtr->nextAdded = 0; chanPtr->curOutPtr->nextRemoved = 0; chanPtr->curOutPtr->bufSize = chanPtr->bufSize; chanPtr->curOutPtr->nextPtr = (ChannelBuffer *) NULL; } outBufPtr = chanPtr->curOutPtr; destCopied = outBufPtr->bufSize - outBufPtr->nextAdded; if (destCopied > slen) { destCopied = slen; } destPtr = outBufPtr->buf + outBufPtr->nextAdded; switch (chanPtr->outputTranslation) { case TCL_TRANSLATE_LF: srcCopied = destCopied; memcpy((VOID *) destPtr, (VOID *) srcPtr, (size_t) destCopied); break; case TCL_TRANSLATE_CR: srcCopied = destCopied; memcpy((VOID *) destPtr, (VOID *) srcPtr, (size_t) destCopied); for (dPtr = destPtr; dPtr < destPtr + destCopied; dPtr++) { if (*dPtr == '\n') { *dPtr = '\r'; } } break; case TCL_TRANSLATE_CRLF: for (srcCopied = 0, dPtr = destPtr, sPtr = srcPtr; dPtr < destPtr + destCopied; dPtr++, sPtr++, srcCopied++) { if (*sPtr == '\n') { if (crsent) { *dPtr = '\n'; crsent = 0; } else { *dPtr = '\r'; crsent = 1; sPtr--, srcCopied--; } } else { *dPtr = *sPtr; } } break; case TCL_TRANSLATE_AUTO: panic("Tcl_Write: AUTO output translation mode not supported"); default: panic("Tcl_Write: unknown output translation mode"); } /* * The current buffer is ready for output if it is full, or if it * contains a newline and this channel is line-buffered, or if it * contains any output and this channel is unbuffered. */ outBufPtr->nextAdded += destCopied; if (!(chanPtr->flags & BUFFER_READY)) { if (outBufPtr->nextAdded == outBufPtr->bufSize) { chanPtr->flags |= BUFFER_READY; } else if (chanPtr->flags & CHANNEL_LINEBUFFERED) { for (sPtr = srcPtr, i = 0, foundNewline = 0; (i < srcCopied) && (!foundNewline); i++, sPtr++) { if (*sPtr == '\n') { foundNewline = 1; break; } } if (foundNewline) { chanPtr->flags |= BUFFER_READY; } } else if (chanPtr->flags & CHANNEL_UNBUFFERED) { chanPtr->flags |= BUFFER_READY; } } totalDestCopied += srcCopied; srcPtr += srcCopied; slen -= srcCopied; if (chanPtr->flags & BUFFER_READY) { if (FlushChannel(NULL, chanPtr, 0) != 0) { return -1; } } } /* Closes "while" */ return totalDestCopied; } /* *---------------------------------------------------------------------- * * Tcl_Flush -- * * Flushes output data on a channel. * * Results: * A standard Tcl result. * * Side effects: * May flush output queued on this channel. * *---------------------------------------------------------------------- */ int Tcl_Flush(chan) Tcl_Channel chan; /* The Channel to flush. */ { int result; /* Of calling FlushChannel. */ Channel *chanPtr; /* The actual channel. */ chanPtr = (Channel *) chan; /* * Check for unreported error. */ if (chanPtr->unreportedError != 0) { Tcl_SetErrno(chanPtr->unreportedError); chanPtr->unreportedError = 0; return TCL_ERROR; } /* * If the channel is not open for writing punt. */ if (!(chanPtr->flags & TCL_WRITABLE)) { Tcl_SetErrno(EACCES); return TCL_ERROR; } /* * If the channel is in the middle of a background copy, fail. */ if (chanPtr->csPtr) { Tcl_SetErrno(EBUSY); return -1; } /* * Force current output buffer to be output also. */ if ((chanPtr->curOutPtr != (ChannelBuffer *) NULL) && (chanPtr->curOutPtr->nextAdded > 0)) { chanPtr->flags |= BUFFER_READY; } result = FlushChannel(NULL, chanPtr, 0); if (result != 0) { return TCL_ERROR; } return TCL_OK; } /* *---------------------------------------------------------------------- * * DiscardInputQueued -- * * Discards any input read from the channel but not yet consumed * by Tcl reading commands. * * Results: * None. * * Side effects: * May discard input from the channel. If discardLastBuffer is zero, * leaves one buffer in place for back-filling. * *---------------------------------------------------------------------- */ static void DiscardInputQueued(chanPtr, discardSavedBuffers) Channel *chanPtr; /* Channel on which to discard * the queued input. */ int discardSavedBuffers; /* If non-zero, discard all buffers including * last one. */ { ChannelBuffer *bufPtr, *nxtPtr; /* Loop variables. */ bufPtr = chanPtr->inQueueHead; chanPtr->inQueueHead = (ChannelBuffer *) NULL; chanPtr->inQueueTail = (ChannelBuffer *) NULL; for (; bufPtr != (ChannelBuffer *) NULL; bufPtr = nxtPtr) { nxtPtr = bufPtr->nextPtr; RecycleBuffer(chanPtr, bufPtr, discardSavedBuffers); } /* * If discardSavedBuffers is nonzero, must also discard any previously * saved buffer in the saveInBufPtr field. */ if (discardSavedBuffers) { if (chanPtr->saveInBufPtr != (ChannelBuffer *) NULL) { ckfree((char *) chanPtr->saveInBufPtr); chanPtr->saveInBufPtr = (ChannelBuffer *) NULL; } } } /* *---------------------------------------------------------------------- * * GetInput -- * * Reads input data from a device or file into an input buffer. * * Results: * A Posix error code or 0. * * Side effects: * Reads from the underlying device. * *---------------------------------------------------------------------- */ static int GetInput(chanPtr) Channel *chanPtr; /* Channel to read input from. */ { int toRead; /* How much to read? */ int result; /* Of calling driver. */ int nread; /* How much was read from channel? */ ChannelBuffer *bufPtr; /* New buffer to add to input queue. */ /* * Prevent reading from a dead channel -- a channel that has been closed * but not yet deallocated, which can happen if the exit handler for * channel cleanup has run but the channel is still registered in some * interpreter. */ if (CheckForDeadChannel(NULL,chanPtr)) return EINVAL; /* * See if we can fill an existing buffer. If we can, read only * as much as will fit in it. Otherwise allocate a new buffer, * add it to the input queue and attempt to fill it to the max. */ if ((chanPtr->inQueueTail != (ChannelBuffer *) NULL) && (chanPtr->inQueueTail->nextAdded < chanPtr->inQueueTail->bufSize)) { bufPtr = chanPtr->inQueueTail; toRead = bufPtr->bufSize - bufPtr->nextAdded; } else { if (chanPtr->saveInBufPtr != (ChannelBuffer *) NULL) { bufPtr = chanPtr->saveInBufPtr; chanPtr->saveInBufPtr = (ChannelBuffer *) NULL; } else { bufPtr = (ChannelBuffer *) ckalloc( ((unsigned) CHANNELBUFFER_HEADER_SIZE + chanPtr->bufSize)); bufPtr->bufSize = chanPtr->bufSize; } bufPtr->nextRemoved = 0; bufPtr->nextAdded = 0; toRead = bufPtr->bufSize; if (chanPtr->inQueueTail == (ChannelBuffer *) NULL) { chanPtr->inQueueHead = bufPtr; } else { chanPtr->inQueueTail->nextPtr = bufPtr; } chanPtr->inQueueTail = bufPtr; bufPtr->nextPtr = (ChannelBuffer *) NULL; } /* * If EOF is set, we should avoid calling the driver because on some * platforms it is impossible to read from a device after EOF. */ if (chanPtr->flags & CHANNEL_EOF) { return 0; } nread = (chanPtr->typePtr->inputProc) (chanPtr->instanceData, bufPtr->buf + bufPtr->nextAdded, toRead, &result); if (nread == 0) { chanPtr->flags |= CHANNEL_EOF; } else if (nread < 0) { if ((result == EWOULDBLOCK) || (result == EAGAIN)) { chanPtr->flags |= CHANNEL_BLOCKED; result = EAGAIN; if (chanPtr->flags & CHANNEL_NONBLOCKING) { Tcl_SetErrno(result); } else { panic("Blocking channel driver did not block on input"); } } else { Tcl_SetErrno(result); } return result; } else { bufPtr->nextAdded += nread; /* * If we get a short read, signal up that we may be BLOCKED. We * should avoid calling the driver because on some platforms we * will block in the low level reading code even though the * channel is set into nonblocking mode. */ if (nread < toRead) { chanPtr->flags |= CHANNEL_BLOCKED; } } return 0; } /* *---------------------------------------------------------------------- * * CopyAndTranslateBuffer -- * * Copy at most one buffer of input to the result space, doing * eol translations according to mode in effect currently. * * Results: * Number of characters (as opposed to bytes) copied. May return * zero if no input is available to be translated. * * Side effects: * Consumes buffered input. May deallocate one buffer. * *---------------------------------------------------------------------- */ static int CopyAndTranslateBuffer(chanPtr, result, space) Channel *chanPtr; /* The channel from which to read input. */ char *result; /* Where to store the copied input. */ int space; /* How many bytes are available in result * to store the copied input? */ { int bytesInBuffer; /* How many bytes are available to be * copied in the current input buffer? */ int copied; /* How many characters were already copied * into the destination space? */ ChannelBuffer *bufPtr; /* The buffer from which to copy bytes. */ char curByte; /* The byte we are currently translating. */ int i; /* Iterates over the copied input looking * for the input eofChar. */ /* * If there is no input at all, return zero. The invariant is that either * there is no buffer in the queue, or if the first buffer is empty, it * is also the last buffer (and thus there is no input in the queue). * Note also that if the buffer is empty, we leave it in the queue. */ if (chanPtr->inQueueHead == (ChannelBuffer *) NULL) { return 0; } bufPtr = chanPtr->inQueueHead; bytesInBuffer = bufPtr->nextAdded - bufPtr->nextRemoved; if (bytesInBuffer < space) { space = bytesInBuffer; } copied = 0; switch (chanPtr->inputTranslation) { case TCL_TRANSLATE_LF: if (space == 0) { return 0; } /* * Copy the current chunk into the result buffer. */ memcpy((VOID *) result, (VOID *)(bufPtr->buf + bufPtr->nextRemoved), (size_t) space); bufPtr->nextRemoved += space; copied = space; break; case TCL_TRANSLATE_CR: if (space == 0) { return 0; } /* * Copy the current chunk into the result buffer, then * replace all \r with \n. */ memcpy((VOID *) result, (VOID *)(bufPtr->buf + bufPtr->nextRemoved), (size_t) space); bufPtr->nextRemoved += space; for (copied = 0; copied < space; copied++) { if (result[copied] == '\r') { result[copied] = '\n'; } } break; case TCL_TRANSLATE_CRLF: /* * If there is a held-back "\r" at EOF, produce it now. */ if (space == 0) { if ((chanPtr->flags & (INPUT_SAW_CR | CHANNEL_EOF)) == (INPUT_SAW_CR | CHANNEL_EOF)) { result[0] = '\r'; chanPtr->flags &= (~(INPUT_SAW_CR)); return 1; } return 0; } /* * Copy the current chunk and replace "\r\n" with "\n" * (but not standalone "\r"!). */ for (copied = 0; (copied < space) && (bufPtr->nextRemoved < bufPtr->nextAdded); copied++) { curByte = bufPtr->buf[bufPtr->nextRemoved]; bufPtr->nextRemoved++; if (curByte == '\r') { if (chanPtr->flags & INPUT_SAW_CR) { result[copied] = '\r'; } else { chanPtr->flags |= INPUT_SAW_CR; copied--; } } else if (curByte == '\n') { chanPtr->flags &= (~(INPUT_SAW_CR)); result[copied] = '\n'; } else { if (chanPtr->flags & INPUT_SAW_CR) { chanPtr->flags &= (~(INPUT_SAW_CR)); result[copied] = '\r'; bufPtr->nextRemoved--; } else { result[copied] = curByte; } } } break; case TCL_TRANSLATE_AUTO: if (space == 0) { return 0; } /* * Loop over the current buffer, converting "\r" and "\r\n" * to "\n". */ for (copied = 0; (copied < space) && (bufPtr->nextRemoved < bufPtr->nextAdded); ) { curByte = bufPtr->buf[bufPtr->nextRemoved]; bufPtr->nextRemoved++; if (curByte == '\r') { result[copied] = '\n'; copied++; if (bufPtr->nextRemoved < bufPtr->nextAdded) { if (bufPtr->buf[bufPtr->nextRemoved] == '\n') { bufPtr->nextRemoved++; } chanPtr->flags &= (~(INPUT_SAW_CR)); } else { chanPtr->flags |= INPUT_SAW_CR; } } else { if (curByte == '\n') { if (!(chanPtr->flags & INPUT_SAW_CR)) { result[copied] = '\n'; copied++; } } else { result[copied] = curByte; copied++; } chanPtr->flags &= (~(INPUT_SAW_CR)); } } break; default: panic("unknown eol translation mode"); } /* * If an in-stream EOF character is set for this channel,, check that * the input we copied so far does not contain the EOF char. If it does, * copy only up to and excluding that character. */ if (chanPtr->inEofChar != 0) { for (i = 0; i < copied; i++) { if (result[i] == (char) chanPtr->inEofChar) { break; } } if (i < copied) { /* * Set sticky EOF so that no further input is presented * to the caller. */ chanPtr->flags |= (CHANNEL_EOF | CHANNEL_STICKY_EOF); /* * Reset the start of valid data in the input buffer to the * position of the eofChar, so that subsequent reads will * encounter it immediately. First we set it to the position * of the last byte consumed if all result bytes were the * product of one input byte; since it is possible that "\r\n" * contracted to "\n" in the result, we have to search back * from that position until we find the eofChar, because it * is possible that its actual position in the buffer is n * bytes further back (n is the number of "\r\n" sequences * that were contracted to "\n" in the result). */ bufPtr->nextRemoved -= (copied - i); while ((bufPtr->nextRemoved > 0) && (bufPtr->buf[bufPtr->nextRemoved] != (char) chanPtr->inEofChar)) { bufPtr->nextRemoved--; } copied = i; } } /* * If the current buffer is empty recycle it. */ if (bufPtr->nextRemoved == bufPtr->nextAdded) { chanPtr->inQueueHead = bufPtr->nextPtr; if (chanPtr->inQueueHead == (ChannelBuffer *) NULL) { chanPtr->inQueueTail = (ChannelBuffer *) NULL; } RecycleBuffer(chanPtr, bufPtr, 0); } /* * Return the number of characters copied into the result buffer. * This may be different from the number of bytes consumed, because * of EOL translations. */ return copied; } /* *---------------------------------------------------------------------- * * ScanBufferForEOL -- * * Scans one buffer for EOL according to the specified EOL * translation mode. If it sees the input eofChar for the channel * it stops also. * * Results: * TRUE if EOL is found, FALSE otherwise. Also sets output parameter * bytesToEOLPtr to the number of bytes so far to EOL, and crSeenPtr * to whether a "\r" was seen. * * Side effects: * None. * *---------------------------------------------------------------------- */ static int ScanBufferForEOL(chanPtr, bufPtr, translation, eofChar, bytesToEOLPtr, crSeenPtr) Channel *chanPtr; ChannelBuffer *bufPtr; /* Buffer to scan for EOL. */ Tcl_EolTranslation translation; /* Translation mode to use. */ int eofChar; /* EOF char to look for. */ int *bytesToEOLPtr; /* Running counter. */ int *crSeenPtr; /* Has "\r" been seen? */ { char *rPtr; /* Iterates over input string. */ char *sPtr; /* Where to stop search? */ int EOLFound; int bytesToEOL; for (EOLFound = 0, rPtr = bufPtr->buf + bufPtr->nextRemoved, sPtr = bufPtr->buf + bufPtr->nextAdded, bytesToEOL = *bytesToEOLPtr; (!EOLFound) && (rPtr < sPtr); rPtr++) { switch (translation) { case TCL_TRANSLATE_AUTO: if ((*rPtr == (char) eofChar) && (eofChar != 0)) { chanPtr->flags |= (CHANNEL_EOF | CHANNEL_STICKY_EOF); EOLFound = 1; } else if (*rPtr == '\n') { /* * CopyAndTranslateBuffer wants to know the length * of the result, not the input. The input is one * larger because "\r\n" shrinks to "\n". */ if (!(*crSeenPtr)) { bytesToEOL++; EOLFound = 1; } else { /* * This is a lf at the begining of a buffer * where the previous buffer ended in a cr. * Consume this lf because we've already emitted * the newline for this crlf sequence. ALSO, if * bytesToEOL is 0 (which means that we are at the * first character of the scan), unset the * INPUT_SAW_CR flag in the channel, because we * already handled it; leaving it set would cause * CopyAndTranslateBuffer to potentially consume * another lf if one follows the current byte. */ bufPtr->nextRemoved++; *crSeenPtr = 0; chanPtr->flags &= (~(INPUT_SAW_CR)); } } else if (*rPtr == '\r') { bytesToEOL++; EOLFound = 1; } else { *crSeenPtr = 0; bytesToEOL++; } break; case TCL_TRANSLATE_LF: if ((*rPtr == (char) eofChar) && (eofChar != 0)) { chanPtr->flags |= (CHANNEL_EOF | CHANNEL_STICKY_EOF); EOLFound = 1; } else { if (*rPtr == '\n') { EOLFound = 1; } bytesToEOL++; } break; case TCL_TRANSLATE_CR: if ((*rPtr == (char) eofChar) && (eofChar != 0)) { chanPtr->flags |= (CHANNEL_EOF | CHANNEL_STICKY_EOF); EOLFound = 1; } else { if (*rPtr == '\r') { EOLFound = 1; } bytesToEOL++; } break; case TCL_TRANSLATE_CRLF: if ((*rPtr == (char) eofChar) && (eofChar != 0)) { chanPtr->flags |= (CHANNEL_EOF | CHANNEL_STICKY_EOF); EOLFound = 1; } else if (*rPtr == '\n') { /* * CopyAndTranslateBuffer wants to know the length * of the result, not the input. The input is one * larger because crlf shrinks to lf. */ if (*crSeenPtr) { EOLFound = 1; } else { bytesToEOL++; } } else { if (*rPtr == '\r') { *crSeenPtr = 1; } else { *crSeenPtr = 0; } bytesToEOL++; } break; default: panic("unknown eol translation mode"); } } *bytesToEOLPtr = bytesToEOL; return EOLFound; } /* *---------------------------------------------------------------------- * * ScanInputForEOL -- * * Scans queued input for chanPtr for an end of line (according to the * current EOL translation mode) and returns the number of bytes * upto and including the end of line, or -1 if none was found. * * Results: * Count of bytes upto and including the end of line if one is present * or -1 if none was found. Also returns in an output parameter the * number of bytes queued if no end of line was found. * * Side effects: * None. * *---------------------------------------------------------------------- */ static int ScanInputForEOL(chanPtr, bytesQueuedPtr) Channel *chanPtr; /* Channel for which to scan queued * input for end of line. */ int *bytesQueuedPtr; /* Where to store the number of bytes * currently queued if no end of line * was found. */ { ChannelBuffer *bufPtr; /* Iterates over queued buffers. */ int bytesToEOL; /* How many bytes to end of line? */ int EOLFound; /* Did we find an end of line? */ int crSeen; /* Did we see a "\r" in CRLF mode? */ *bytesQueuedPtr = 0; bytesToEOL = 0; EOLFound = 0; for (bufPtr = chanPtr->inQueueHead, crSeen = (chanPtr->flags & INPUT_SAW_CR) ? 1 : 0; (!EOLFound) && (bufPtr != (ChannelBuffer *) NULL); bufPtr = bufPtr->nextPtr) { EOLFound = ScanBufferForEOL(chanPtr, bufPtr, chanPtr->inputTranslation, chanPtr->inEofChar, &bytesToEOL, &crSeen); } if (EOLFound == 0) { *bytesQueuedPtr = bytesToEOL; return -1; } return bytesToEOL; } /* *---------------------------------------------------------------------- * * GetEOL -- * * Accumulate input into the channel input buffer queue until an * end of line has been seen. * * Results: * Number of bytes buffered (at least 1) or -1 on failure. * * Side effects: * Consumes input from the channel. * *---------------------------------------------------------------------- */ static int GetEOL(chanPtr) Channel *chanPtr; /* Channel to queue input on. */ { int bytesToEOL; /* How many bytes in buffer up to and * including the end of line? */ int bytesQueued; /* How many bytes are queued currently * in the input chain of the channel? */ /* * Check for unreported error. */ if (chanPtr->unreportedError != 0) { Tcl_SetErrno(chanPtr->unreportedError); chanPtr->unreportedError = 0; return -1; } /* * Punt if the channel is not opened for reading. */ if (!(chanPtr->flags & TCL_READABLE)) { Tcl_SetErrno(EACCES); return -1; } /* * If the channel is in the middle of a background copy, fail. */ if (chanPtr->csPtr) { Tcl_SetErrno(EBUSY); return -1; } /* * If we have not encountered a sticky EOF, clear the EOF bit * (sticky EOF is set if we have seen the input eofChar, to prevent * reading beyond the eofChar). Also, always clear the BLOCKED bit. * We want to discover these conditions anew in each operation. */ if (!(chanPtr->flags & CHANNEL_STICKY_EOF)) { chanPtr->flags &= (~(CHANNEL_EOF)); } chanPtr->flags &= (~(CHANNEL_BLOCKED | CHANNEL_GETS_BLOCKED)); while (1) { bytesToEOL = ScanInputForEOL(chanPtr, &bytesQueued); if (bytesToEOL > 0) { chanPtr->flags &= (~(CHANNEL_BLOCKED)); return bytesToEOL; } if (chanPtr->flags & CHANNEL_EOF) { /* * Boundary case where cr was at the end of the previous buffer * and this buffer just has a newline. At EOF our caller wants * to see -1 for the line length. */ return (bytesQueued == 0) ? -1 : bytesQueued ; } if (chanPtr->flags & CHANNEL_BLOCKED) { if (chanPtr->flags & CHANNEL_NONBLOCKING) { goto blocked; } chanPtr->flags &= (~(CHANNEL_BLOCKED)); } if (GetInput(chanPtr) != 0) { goto blocked; } } blocked: /* * We didn't get a complete line so we need to indicate to UpdateInterest * that the gets blocked. It will wait for more data instead of firing * a timer, avoiding a busy wait. This is where we are assuming that the * next operation is a gets. No more file events will be delivered on * this channel until new data arrives or some operation is performed * on the channel (e.g. gets, read, fconfigure) that changes the blocking * state. Note that this means a file event will not be delivered even * though a read would be able to consume the buffered data. */ chanPtr->flags |= CHANNEL_GETS_BLOCKED; return -1; } /* *---------------------------------------------------------------------- * * Tcl_Read -- * * Reads a given number of characters from a channel. * * Results: * The number of characters read, or -1 on error. Use Tcl_GetErrno() * to retrieve the error code for the error that occurred. * * Side effects: * May cause input to be buffered. * *---------------------------------------------------------------------- */ int Tcl_Read(chan, bufPtr, toRead) Tcl_Channel chan; /* The channel from which to read. */ char *bufPtr; /* Where to store input read. */ int toRead; /* Maximum number of characters to read. */ { Channel *chanPtr; /* The real IO channel. */ chanPtr = (Channel *) chan; /* * Check for unreported error. */ if (chanPtr->unreportedError != 0) { Tcl_SetErrno(chanPtr->unreportedError); chanPtr->unreportedError = 0; return -1; } /* * Punt if the channel is not opened for reading. */ if (!(chanPtr->flags & TCL_READABLE)) { Tcl_SetErrno(EACCES); return -1; } /* * If the channel is in the middle of a background copy, fail. */ if (chanPtr->csPtr) { Tcl_SetErrno(EBUSY); return -1; } return DoRead(chanPtr, bufPtr, toRead); } /* *---------------------------------------------------------------------- * * DoRead -- * * Reads a given number of characters from a channel. * * Results: * The number of characters read, or -1 on error. Use Tcl_GetErrno() * to retrieve the error code for the error that occurred. * * Side effects: * May cause input to be buffered. * *---------------------------------------------------------------------- */ static int DoRead(chanPtr, bufPtr, toRead) Channel *chanPtr; /* The channel from which to read. */ char *bufPtr; /* Where to store input read. */ int toRead; /* Maximum number of characters to read. */ { int copied; /* How many characters were copied into * the result string? */ int copiedNow; /* How many characters were copied from * the current input buffer? */ int result; /* Of calling GetInput. */ /* * If we have not encountered a sticky EOF, clear the EOF bit. Either * way clear the BLOCKED bit. We want to discover these anew during * each operation. */ if (!(chanPtr->flags & CHANNEL_STICKY_EOF)) { chanPtr->flags &= (~(CHANNEL_EOF)); } chanPtr->flags &= (~(CHANNEL_BLOCKED | CHANNEL_GETS_BLOCKED)); for (copied = 0; copied < toRead; copied += copiedNow) { copiedNow = CopyAndTranslateBuffer(chanPtr, bufPtr + copied, toRead - copied); if (copiedNow == 0) { if (chanPtr->flags & CHANNEL_EOF) { goto done; } if (chanPtr->flags & CHANNEL_BLOCKED) { if (chanPtr->flags & CHANNEL_NONBLOCKING) { goto done; } chanPtr->flags &= (~(CHANNEL_BLOCKED)); } result = GetInput(chanPtr); if (result != 0) { if (result != EAGAIN) { copied = -1; } goto done; } } } chanPtr->flags &= (~(CHANNEL_BLOCKED)); done: /* * Update the notifier state so we don't block while there is still * data in the buffers. */ UpdateInterest(chanPtr); return copied; } /* *---------------------------------------------------------------------- * * Tcl_Gets -- * * Reads a complete line of input from the channel into a * Tcl_DString. * * Results: * Length of line read or -1 if error, EOF or blocked. If -1, use * Tcl_GetErrno() to retrieve the POSIX error code for the * error or condition that occurred. * * Side effects: * May flush output on the channel. May cause input to be * consumed from the channel. * *---------------------------------------------------------------------- */ int Tcl_Gets(chan, lineRead) Tcl_Channel chan; /* Channel from which to read. */ Tcl_DString *lineRead; /* The characters of the line read * (excluding the terminating newline if * present) will be appended to this * DString. The caller must have initialized * it and is responsible for managing the * storage. */ { Channel *chanPtr; /* The channel to read from. */ char *buf; /* Points into DString where data * will be stored. */ int offset; /* Offset from start of DString at * which to append the line just read. */ int copiedTotal; /* Accumulates total length of input copied. */ int copiedNow; /* How many bytes were copied from the * current input buffer? */ int lineLen; /* Length of line read, including the * translated newline. If this is zero * and neither EOF nor BLOCKED is set, * the current line is empty. */ chanPtr = (Channel *) chan; lineLen = GetEOL(chanPtr); if (lineLen < 0) { copiedTotal = -1; goto done; } offset = Tcl_DStringLength(lineRead); Tcl_DStringSetLength(lineRead, lineLen + offset); buf = Tcl_DStringValue(lineRead) + offset; for (copiedTotal = 0; copiedTotal < lineLen; copiedTotal += copiedNow) { copiedNow = CopyAndTranslateBuffer(chanPtr, buf + copiedTotal, lineLen - copiedTotal); } if ((copiedTotal > 0) && (buf[copiedTotal - 1] == '\n')) { copiedTotal--; } Tcl_DStringSetLength(lineRead, copiedTotal + offset); done: /* * Update the notifier state so we don't block while there is still * data in the buffers. */ UpdateInterest(chanPtr); return copiedTotal; } /* *---------------------------------------------------------------------- * * Tcl_GetsObj -- * * Reads a complete line of input from the channel into a * string object. * * Results: * Length of line read or -1 if error, EOF or blocked. If -1, use * Tcl_GetErrno() to retrieve the POSIX error code for the * error or condition that occurred. * * Side effects: * May flush output on the channel. May cause input to be * consumed from the channel. * *---------------------------------------------------------------------- */ int Tcl_GetsObj(chan, objPtr) Tcl_Channel chan; /* Channel from which to read. */ Tcl_Obj *objPtr; /* The characters of the line read * (excluding the terminating newline if * present) will be appended to this * object. The caller must have initialized * it and is responsible for managing the * storage. */ { Channel *chanPtr; /* The channel to read from. */ char *buf; /* Points into DString where data * will be stored. */ int offset; /* Offset from start of DString at * which to append the line just read. */ int copiedTotal; /* Accumulates total length of input copied. */ int copiedNow; /* How many bytes were copied from the * current input buffer? */ int lineLen; /* Length of line read, including the * translated newline. If this is zero * and neither EOF nor BLOCKED is set, * the current line is empty. */ chanPtr = (Channel *) chan; lineLen = GetEOL(chanPtr); if (lineLen < 0) { copiedTotal = -1; goto done; } (void) Tcl_GetStringFromObj(objPtr, &offset); Tcl_SetObjLength(objPtr, lineLen + offset); buf = Tcl_GetStringFromObj(objPtr, NULL) + offset; for (copiedTotal = 0; copiedTotal < lineLen; copiedTotal += copiedNow) { copiedNow = CopyAndTranslateBuffer(chanPtr, buf + copiedTotal, lineLen - copiedTotal); } if ((copiedTotal > 0) && (buf[copiedTotal - 1] == '\n')) { copiedTotal--; } Tcl_SetObjLength(objPtr, copiedTotal + offset); done: /* * Update the notifier state so we don't block while there is still * data in the buffers. */ UpdateInterest(chanPtr); return copiedTotal; } /* *---------------------------------------------------------------------- * * Tcl_Ungets -- * * Causes the supplied string to be added to the input queue of * the channel, at either the head or tail of the queue. * * Results: * The number of bytes stored in the channel, or -1 on error. * * Side effects: * Adds input to the input queue of a channel. * *---------------------------------------------------------------------- */ int Tcl_Ungets(chan, str, len, atEnd) Tcl_Channel chan; /* The channel for which to add the input. */ char *str; /* The input itself. */ int len; /* The length of the input. */ int atEnd; /* If non-zero, add at end of queue; otherwise * add at head of queue. */ { Channel *chanPtr; /* The real IO channel. */ ChannelBuffer *bufPtr; /* Buffer to contain the data. */ int i; chanPtr = (Channel *) chan; /* * Check for unreported error. */ if (chanPtr->unreportedError != 0) { Tcl_SetErrno(chanPtr->unreportedError); chanPtr->unreportedError = 0; return -1; } /* * Punt if the channel is not opened for reading. */ if (!(chanPtr->flags & TCL_READABLE)) { Tcl_SetErrno(EACCES); return -1; } /* * If the channel is in the middle of a background copy, fail. */ if (chanPtr->csPtr) { Tcl_SetErrno(EBUSY); return -1; } /* * If we have encountered a sticky EOF, just punt without storing. * (sticky EOF is set if we have seen the input eofChar, to prevent * reading beyond the eofChar). Otherwise, clear the EOF flags, and * clear the BLOCKED bit. We want to discover these conditions anew * in each operation. */ if (chanPtr->flags & CHANNEL_STICKY_EOF) { return len; } chanPtr->flags &= (~(CHANNEL_BLOCKED | CHANNEL_EOF)); bufPtr = (ChannelBuffer *) ckalloc((unsigned) (CHANNELBUFFER_HEADER_SIZE + len)); for (i = 0; i < len; i++) { bufPtr->buf[i] = str[i]; } bufPtr->bufSize = len; bufPtr->nextAdded = len; bufPtr->nextRemoved = 0; if (chanPtr->inQueueHead == (ChannelBuffer *) NULL) { bufPtr->nextPtr = (ChannelBuffer *) NULL; chanPtr->inQueueHead = bufPtr; chanPtr->inQueueTail = bufPtr; } else if (atEnd) { bufPtr->nextPtr = (ChannelBuffer *) NULL; chanPtr->inQueueTail->nextPtr = bufPtr; chanPtr->inQueueTail = bufPtr; } else { bufPtr->nextPtr = chanPtr->inQueueHead; chanPtr->inQueueHead = bufPtr; } /* * Update the notifier state so we don't block while there is still * data in the buffers. */ UpdateInterest(chanPtr); return len; } /* *---------------------------------------------------------------------- * * Tcl_Seek -- * * Implements seeking on Tcl Channels. This is a public function * so that other C facilities may be implemented on top of it. * * Results: * The new access point or -1 on error. If error, use Tcl_GetErrno() * to retrieve the POSIX error code for the error that occurred. * * Side effects: * May flush output on the channel. May discard queued input. * *---------------------------------------------------------------------- */ int Tcl_Seek(chan, offset, mode) Tcl_Channel chan; /* The channel on which to seek. */ int offset; /* Offset to seek to. */ int mode; /* Relative to which location to seek? */ { Channel *chanPtr; /* The real IO channel. */ ChannelBuffer *bufPtr; int inputBuffered, outputBuffered; int result; /* Of device driver operations. */ int curPos; /* Position on the device. */ int wasAsync; /* Was the channel nonblocking before the * seek operation? If so, must restore to * nonblocking mode after the seek. */ chanPtr = (Channel *) chan; /* * Check for unreported error. */ if (chanPtr->unreportedError != 0) { Tcl_SetErrno(chanPtr->unreportedError); chanPtr->unreportedError = 0; return -1; } /* * Disallow seek on channels that are open for neither writing nor * reading (e.g. socket server channels). */ if (!(chanPtr->flags & (TCL_WRITABLE|TCL_READABLE))) { Tcl_SetErrno(EACCES); return -1; } /* * If the channel is in the middle of a background copy, fail. */ if (chanPtr->csPtr) { Tcl_SetErrno(EBUSY); return -1; } /* * Disallow seek on dead channels -- channels that have been closed but * not yet been deallocated. Such channels can be found if the exit * handler for channel cleanup has run but the channel is still * registered in an interpreter. */ if (CheckForDeadChannel(NULL,chanPtr)) return -1; /* * Disallow seek on channels whose type does not have a seek procedure * defined. This means that the channel does not support seeking. */ if (chanPtr->typePtr->seekProc == (Tcl_DriverSeekProc *) NULL) { Tcl_SetErrno(EINVAL); return -1; } /* * Compute how much input and output is buffered. If both input and * output is buffered, cannot compute the current position. */ for (bufPtr = chanPtr->inQueueHead, inputBuffered = 0; bufPtr != (ChannelBuffer *) NULL; bufPtr = bufPtr->nextPtr) { inputBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); } for (bufPtr = chanPtr->outQueueHead, outputBuffered = 0; bufPtr != (ChannelBuffer *) NULL; bufPtr = bufPtr->nextPtr) { outputBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); } if ((chanPtr->curOutPtr != (ChannelBuffer *) NULL) && (chanPtr->curOutPtr->nextAdded > chanPtr->curOutPtr->nextRemoved)) { chanPtr->flags |= BUFFER_READY; outputBuffered += (chanPtr->curOutPtr->nextAdded - chanPtr->curOutPtr->nextRemoved); } if ((inputBuffered != 0) && (outputBuffered != 0)) { Tcl_SetErrno(EFAULT); return -1; } /* * If we are seeking relative to the current position, compute the * corrected offset taking into account the amount of unread input. */ if (mode == SEEK_CUR) { offset -= inputBuffered; } /* * Discard any queued input - this input should not be read after * the seek. */ DiscardInputQueued(chanPtr, 0); /* * Reset EOF and BLOCKED flags. We invalidate them by moving the * access point. Also clear CR related flags. */ chanPtr->flags &= (~(CHANNEL_EOF | CHANNEL_STICKY_EOF | CHANNEL_BLOCKED | INPUT_SAW_CR)); /* * If the channel is in asynchronous output mode, switch it back * to synchronous mode and cancel any async flush that may be * scheduled. After the flush, the channel will be put back into * asynchronous output mode. */ wasAsync = 0; if (chanPtr->flags & CHANNEL_NONBLOCKING) { wasAsync = 1; result = 0; if (chanPtr->typePtr->blockModeProc != NULL) { result = (chanPtr->typePtr->blockModeProc) (chanPtr->instanceData, TCL_MODE_BLOCKING); } if (result != 0) { Tcl_SetErrno(result); return -1; } chanPtr->flags &= (~(CHANNEL_NONBLOCKING)); if (chanPtr->flags & BG_FLUSH_SCHEDULED) { chanPtr->flags &= (~(BG_FLUSH_SCHEDULED)); } } /* * If the flush fails we cannot recover the original position. In * that case the seek is not attempted because we do not know where * the access position is - instead we return the error. FlushChannel * has already called Tcl_SetErrno() to report the error upwards. * If the flush succeeds we do the seek also. */ if (FlushChannel(NULL, chanPtr, 0) != 0) { curPos = -1; } else { /* * Now seek to the new position in the channel as requested by the * caller. */ curPos = (chanPtr->typePtr->seekProc) (chanPtr->instanceData, (long) offset, mode, &result); if (curPos == -1) { Tcl_SetErrno(result); } } /* * Restore to nonblocking mode if that was the previous behavior. * * NOTE: Even if there was an async flush active we do not restore * it now because we already flushed all the queued output, above. */ if (wasAsync) { chanPtr->flags |= CHANNEL_NONBLOCKING; result = 0; if (chanPtr->typePtr->blockModeProc != NULL) { result = (chanPtr->typePtr->blockModeProc) (chanPtr->instanceData, TCL_MODE_NONBLOCKING); } if (result != 0) { Tcl_SetErrno(result); return -1; } } return curPos; } /* *---------------------------------------------------------------------- * * Tcl_Tell -- * * Returns the position of the next character to be read/written on * this channel. * * Results: * A nonnegative integer on success, -1 on failure. If failed, * use Tcl_GetErrno() to retrieve the POSIX error code for the * error that occurred. * * Side effects: * None. * *---------------------------------------------------------------------- */ int Tcl_Tell(chan) Tcl_Channel chan; /* The channel to return pos for. */ { Channel *chanPtr; /* The actual channel to tell on. */ ChannelBuffer *bufPtr; int inputBuffered, outputBuffered; int result; /* Of calling device driver. */ int curPos; /* Position on device. */ chanPtr = (Channel *) chan; /* * Check for unreported error. */ if (chanPtr->unreportedError != 0) { Tcl_SetErrno(chanPtr->unreportedError); chanPtr->unreportedError = 0; return -1; } /* * Disallow tell on dead channels -- channels that have been closed but * not yet been deallocated. Such channels can be found if the exit * handler for channel cleanup has run but the channel is still * registered in an interpreter. */ if (CheckForDeadChannel(NULL,chanPtr)) return -1; /* * Disallow tell on channels that are open for neither * writing nor reading (e.g. socket server channels). */ if (!(chanPtr->flags & (TCL_WRITABLE|TCL_READABLE))) { Tcl_SetErrno(EACCES); return -1; } /* * If the channel is in the middle of a background copy, fail. */ if (chanPtr->csPtr) { Tcl_SetErrno(EBUSY); return -1; } /* * Disallow tell on channels whose type does not have a seek procedure * defined. This means that the channel does not support seeking. */ if (chanPtr->typePtr->seekProc == (Tcl_DriverSeekProc *) NULL) { Tcl_SetErrno(EINVAL); return -1; } /* * Compute how much input and output is buffered. If both input and * output is buffered, cannot compute the current position. */ for (bufPtr = chanPtr->inQueueHead, inputBuffered = 0; bufPtr != (ChannelBuffer *) NULL; bufPtr = bufPtr->nextPtr) { inputBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); } for (bufPtr = chanPtr->outQueueHead, outputBuffered = 0; bufPtr != (ChannelBuffer *) NULL; bufPtr = bufPtr->nextPtr) { outputBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); } if ((chanPtr->curOutPtr != (ChannelBuffer *) NULL) && (chanPtr->curOutPtr->nextAdded > chanPtr->curOutPtr->nextRemoved)) { chanPtr->flags |= BUFFER_READY; outputBuffered += (chanPtr->curOutPtr->nextAdded - chanPtr->curOutPtr->nextRemoved); } if ((inputBuffered != 0) && (outputBuffered != 0)) { Tcl_SetErrno(EFAULT); return -1; } /* * Get the current position in the device and compute the position * where the next character will be read or written. */ curPos = (chanPtr->typePtr->seekProc) (chanPtr->instanceData, (long) 0, SEEK_CUR, &result); if (curPos == -1) { Tcl_SetErrno(result); return -1; } if (inputBuffered != 0) { return (curPos - inputBuffered); } return (curPos + outputBuffered); } /* *---------------------------------------------------------------------- * * Tcl_Eof -- * * Returns 1 if the channel is at EOF, 0 otherwise. * * Results: * 1 or 0, always. * * Side effects: * None. * *---------------------------------------------------------------------- */ int Tcl_Eof(chan) Tcl_Channel chan; /* Does this channel have EOF? */ { Channel *chanPtr; /* The real channel structure. */ chanPtr = (Channel *) chan; return ((chanPtr->flags & CHANNEL_STICKY_EOF) || ((chanPtr->flags & CHANNEL_EOF) && (Tcl_InputBuffered(chan) == 0))) ? 1 : 0; } /* *---------------------------------------------------------------------- * * Tcl_InputBlocked -- * * Returns 1 if input is blocked on this channel, 0 otherwise. * * Results: * 0 or 1, always. * * Side effects: * None. * *---------------------------------------------------------------------- */ int Tcl_InputBlocked(chan) Tcl_Channel chan; /* Is this channel blocked? */ { Channel *chanPtr; /* The real channel structure. */ chanPtr = (Channel *) chan; return (chanPtr->flags & CHANNEL_BLOCKED) ? 1 : 0; } /* *---------------------------------------------------------------------- * * Tcl_InputBuffered -- * * Returns the number of bytes of input currently buffered in the * internal buffer of a channel. * * Results: * The number of input bytes buffered, or zero if the channel is not * open for reading. * * Side effects: * None. * *---------------------------------------------------------------------- */ int Tcl_InputBuffered(chan) Tcl_Channel chan; /* The channel to query. */ { Channel *chanPtr; int bytesBuffered; ChannelBuffer *bufPtr; chanPtr = (Channel *) chan; for (bytesBuffered = 0, bufPtr = chanPtr->inQueueHead; bufPtr != (ChannelBuffer *) NULL; bufPtr = bufPtr->nextPtr) { bytesBuffered += (bufPtr->nextAdded - bufPtr->nextRemoved); } return bytesBuffered; } /* *---------------------------------------------------------------------- * * Tcl_SetChannelBufferSize -- * * Sets the size of buffers to allocate to store input or output * in the channel. The size must be between 10 bytes and 1 MByte. * * Results: * None. * * Side effects: * Sets the size of buffers subsequently allocated for this channel. * *---------------------------------------------------------------------- */ void Tcl_SetChannelBufferSize(chan, sz) Tcl_Channel chan; /* The channel whose buffer size * to set. */ int sz; /* The size to set. */ { Channel *chanPtr; /* * If the buffer size is smaller than 10 bytes or larger than one MByte, * do not accept the requested size and leave the current buffer size. */ if (sz < 10) { return; } if (sz > (1024 * 1024)) { return; } chanPtr = (Channel *) chan; chanPtr->bufSize = sz; } /* *---------------------------------------------------------------------- * * Tcl_GetChannelBufferSize -- * * Retrieves the size of buffers to allocate for this channel. * * Results: * The size. * * Side effects: * None. * *---------------------------------------------------------------------- */ int Tcl_GetChannelBufferSize(chan) Tcl_Channel chan; /* The channel for which to find the * buffer size. */ { Channel *chanPtr; chanPtr = (Channel *) chan; return chanPtr->bufSize; } /* *---------------------------------------------------------------------- * * Tcl_BadChannelOption -- * * This procedure generates a "bad option" error message in an * (optional) interpreter. It is used by channel drivers when * a invalid Set/Get option is requested. Its purpose is to concatenate * the generic options list to the specific ones and factorize * the generic options error message string. * * Results: * TCL_ERROR. * * Side effects: * An error message is generated in interp's result object to * indicate that a command was invoked with the a bad option * The message has the form * bad option "blah": should be one of * <...generic options...>+<...specific options...> * "blah" is the optionName argument and "<specific options>" * is a space separated list of specific option words. * The function takes good care of inserting minus signs before * each option, commas after, and an "or" before the last option. * *---------------------------------------------------------------------- */ int Tcl_BadChannelOption(interp, optionName, optionList) Tcl_Interp *interp; /* Current interpreter. (can be NULL)*/ char *optionName; /* 'bad option' name */ char *optionList; /* Specific options list to append * to the standard generic options. * can be NULL for generic options * only. */ { if (interp) { CONST char *genericopt = "blocking buffering buffersize eofchar translation"; char **argv; int argc, i; Tcl_DString ds; Tcl_DStringInit(&ds); Tcl_DStringAppend(&ds, (char *) genericopt, -1); if (optionList && (*optionList)) { Tcl_DStringAppend(&ds, " ", 1); Tcl_DStringAppend(&ds, optionList, -1); } if (Tcl_SplitList(interp, Tcl_DStringValue(&ds), &argc, &argv) != TCL_OK) { panic("malformed option list in channel driver"); } Tcl_ResetResult(interp); Tcl_AppendResult(interp, "bad option \"", optionName, "\": should be one of ", (char *) NULL); argc--; for (i = 0; i < argc; i++) { Tcl_AppendResult(interp, "-", argv[i], ", ", (char *) NULL); } Tcl_AppendResult(interp, "or -", argv[i], (char *) NULL); Tcl_DStringFree(&ds); ckfree((char *) argv); } Tcl_SetErrno(EINVAL); return TCL_ERROR; } /* *---------------------------------------------------------------------- * * Tcl_GetChannelOption -- * * Gets a mode associated with an IO channel. If the optionName arg * is non NULL, retrieves the value of that option. If the optionName * arg is NULL, retrieves a list of alternating option names and * values for the given channel. * * Results: * A standard Tcl result. Also sets the supplied DString to the * string value of the option(s) returned. * * Side effects: * None. * *---------------------------------------------------------------------- */ int Tcl_GetChannelOption(interp, chan, optionName, dsPtr) Tcl_Interp *interp; /* For error reporting - can be NULL. */ Tcl_Channel chan; /* Channel on which to get option. */ char *optionName; /* Option to get. */ Tcl_DString *dsPtr; /* Where to store value(s). */ { size_t len; /* Length of optionName string. */ char optionVal[128]; /* Buffer for sprintf. */ Channel *chanPtr = (Channel *) chan; int flags; /* * If we are in the middle of a background copy, use the saved flags. */ if (chanPtr->csPtr) { if (chanPtr == chanPtr->csPtr->readPtr) { flags = chanPtr->csPtr->readFlags; } else { flags = chanPtr->csPtr->writeFlags; } } else { flags = chanPtr->flags; } /* * Disallow options on dead channels -- channels that have been closed but * not yet been deallocated. Such channels can be found if the exit * handler for channel cleanup has run but the channel is still * registered in an interpreter. */ if (CheckForDeadChannel(interp,chanPtr)) return TCL_ERROR; /* * If the optionName is NULL it means that we want a list of all * options and values. */ if (optionName == (char *) NULL) { len = 0; } else { len = strlen(optionName); } if ((len == 0) || ((len > 2) && (optionName[1] == 'b') && (strncmp(optionName, "-blocking", len) == 0))) { if (len == 0) { Tcl_DStringAppendElement(dsPtr, "-blocking"); } Tcl_DStringAppendElement(dsPtr, (flags & CHANNEL_NONBLOCKING) ? "0" : "1"); if (len > 0) { return TCL_OK; } } if ((len == 0) || ((len > 7) && (optionName[1] == 'b') && (strncmp(optionName, "-buffering", len) == 0))) { if (len == 0) { Tcl_DStringAppendElement(dsPtr, "-buffering"); } if (flags & CHANNEL_LINEBUFFERED) { Tcl_DStringAppendElement(dsPtr, "line"); } else if (flags & CHANNEL_UNBUFFERED) { Tcl_DStringAppendElement(dsPtr, "none"); } else { Tcl_DStringAppendElement(dsPtr, "full"); } if (len > 0) { return TCL_OK; } } if ((len == 0) || ((len > 7) && (optionName[1] == 'b') && (strncmp(optionName, "-buffersize", len) == 0))) { if (len == 0) { Tcl_DStringAppendElement(dsPtr, "-buffersize"); } TclFormatInt(optionVal, chanPtr->bufSize); Tcl_DStringAppendElement(dsPtr, optionVal); if (len > 0) { return TCL_OK; } } if ((len == 0) || ((len > 1) && (optionName[1] == 'e') && (strncmp(optionName, "-eofchar", len) == 0))) { if (len == 0) { Tcl_DStringAppendElement(dsPtr, "-eofchar"); } if (((flags & (TCL_READABLE|TCL_WRITABLE)) == (TCL_READABLE|TCL_WRITABLE)) && (len == 0)) { Tcl_DStringStartSublist(dsPtr); } if (flags & TCL_READABLE) { if (chanPtr->inEofChar == 0) { Tcl_DStringAppendElement(dsPtr, ""); } else { char buf[4]; sprintf(buf, "%c", chanPtr->inEofChar); Tcl_DStringAppendElement(dsPtr, buf); } } if (flags & TCL_WRITABLE) { if (chanPtr->outEofChar == 0) { Tcl_DStringAppendElement(dsPtr, ""); } else { char buf[4]; sprintf(buf, "%c", chanPtr->outEofChar); Tcl_DStringAppendElement(dsPtr, buf); } } if (((flags & (TCL_READABLE|TCL_WRITABLE)) == (TCL_READABLE|TCL_WRITABLE)) && (len == 0)) { Tcl_DStringEndSublist(dsPtr); } if (len > 0) { return TCL_OK; } } if ((len == 0) || ((len > 1) && (optionName[1] == 't') && (strncmp(optionName, "-translation", len) == 0))) { if (len == 0) { Tcl_DStringAppendElement(dsPtr, "-translation"); } if (((flags & (TCL_READABLE|TCL_WRITABLE)) == (TCL_READABLE|TCL_WRITABLE)) && (len == 0)) { Tcl_DStringStartSublist(dsPtr); } if (flags & TCL_READABLE) { if (chanPtr->inputTranslation == TCL_TRANSLATE_AUTO) { Tcl_DStringAppendElement(dsPtr, "auto"); } else if (chanPtr->inputTranslation == TCL_TRANSLATE_CR) { Tcl_DStringAppendElement(dsPtr, "cr"); } else if (chanPtr->inputTranslation == TCL_TRANSLATE_CRLF) { Tcl_DStringAppendElement(dsPtr, "crlf"); } else { Tcl_DStringAppendElement(dsPtr, "lf"); } } if (flags & TCL_WRITABLE) { if (chanPtr->outputTranslation == TCL_TRANSLATE_AUTO) { Tcl_DStringAppendElement(dsPtr, "auto"); } else if (chanPtr->outputTranslation == TCL_TRANSLATE_CR) { Tcl_DStringAppendElement(dsPtr, "cr"); } else if (chanPtr->outputTranslation == TCL_TRANSLATE_CRLF) { Tcl_DStringAppendElement(dsPtr, "crlf"); } else { Tcl_DStringAppendElement(dsPtr, "lf"); } } if (((flags & (TCL_READABLE|TCL_WRITABLE)) == (TCL_READABLE|TCL_WRITABLE)) && (len == 0)) { Tcl_DStringEndSublist(dsPtr); } if (len > 0) { return TCL_OK; } } if (chanPtr->typePtr->getOptionProc != (Tcl_DriverGetOptionProc *) NULL) { /* * let the driver specific handle additional options * and result code and message. */ return (chanPtr->typePtr->getOptionProc) (chanPtr->instanceData, interp, optionName, dsPtr); } else { /* * no driver specific options case. */ if (len == 0) { return TCL_OK; } return Tcl_BadChannelOption(interp, optionName, NULL); } } /* *---------------------------------------------------------------------- * * Tcl_SetChannelOption -- * * Sets an option on a channel. * * Results: * A standard Tcl result. Also sets interp->result on error if * interp is not NULL. * * Side effects: * May modify an option on a device. * *---------------------------------------------------------------------- */ int Tcl_SetChannelOption(interp, chan, optionName, newValue) Tcl_Interp *interp; /* For error reporting - can be NULL. */ Tcl_Channel chan; /* Channel on which to set mode. */ char *optionName; /* Which option to set? */ char *newValue; /* New value for option. */ { int newMode; /* New (numeric) mode to sert. */ Channel *chanPtr; /* The real IO channel. */ size_t len; /* Length of optionName string. */ int argc; char **argv; chanPtr = (Channel *) chan; /* * If the channel is in the middle of a background copy, fail. */ if (chanPtr->csPtr) { if (interp) { Tcl_AppendResult(interp, "unable to set channel options: background copy in progress", (char *) NULL); } return TCL_ERROR; } /* * Disallow options on dead channels -- channels that have been closed but * not yet been deallocated. Such channels can be found if the exit * handler for channel cleanup has run but the channel is still * registered in an interpreter. */ if (CheckForDeadChannel(NULL,chanPtr)) return TCL_ERROR; len = strlen(optionName); if ((len > 2) && (optionName[1] == 'b') && (strncmp(optionName, "-blocking", len) == 0)) { if (Tcl_GetBoolean(interp, newValue, &newMode) == TCL_ERROR) { return TCL_ERROR; } if (newMode) { newMode = TCL_MODE_BLOCKING; } else { newMode = TCL_MODE_NONBLOCKING; } return SetBlockMode(interp, chanPtr, newMode); } if ((len > 7) && (optionName[1] == 'b') && (strncmp(optionName, "-buffering", len) == 0)) { len = strlen(newValue); if ((newValue[0] == 'f') && (strncmp(newValue, "full", len) == 0)) { chanPtr->flags &= (~(CHANNEL_UNBUFFERED|CHANNEL_LINEBUFFERED)); } else if ((newValue[0] == 'l') && (strncmp(newValue, "line", len) == 0)) { chanPtr->flags &= (~(CHANNEL_UNBUFFERED)); chanPtr->flags |= CHANNEL_LINEBUFFERED; } else if ((newValue[0] == 'n') && (strncmp(newValue, "none", len) == 0)) { chanPtr->flags &= (~(CHANNEL_LINEBUFFERED)); chanPtr->flags |= CHANNEL_UNBUFFERED; } else { if (interp) { Tcl_AppendResult(interp, "bad value for -buffering: ", "must be one of full, line, or none", (char *) NULL); return TCL_ERROR; } } return TCL_OK; } if ((len > 7) && (optionName[1] == 'b') && (strncmp(optionName, "-buffersize", len) == 0)) { chanPtr->bufSize = atoi(newValue); if ((chanPtr->bufSize < 10) || (chanPtr->bufSize > (1024 * 1024))) { chanPtr->bufSize = CHANNELBUFFER_DEFAULT_SIZE; } return TCL_OK; } if ((len > 1) && (optionName[1] == 'e') && (strncmp(optionName, "-eofchar", len) == 0)) { if (Tcl_SplitList(interp, newValue, &argc, &argv) == TCL_ERROR) { return TCL_ERROR; } if (argc == 0) { chanPtr->inEofChar = 0; chanPtr->outEofChar = 0; } else if (argc == 1) { if (chanPtr->flags & TCL_WRITABLE) { chanPtr->outEofChar = (int) argv[0][0]; } if (chanPtr->flags & TCL_READABLE) { chanPtr->inEofChar = (int) argv[0][0]; } } else if (argc != 2) { if (interp) { Tcl_AppendResult(interp, "bad value for -eofchar: should be a list of one or", " two elements", (char *) NULL); } ckfree((char *) argv); return TCL_ERROR; } else { if (chanPtr->flags & TCL_READABLE) { chanPtr->inEofChar = (int) argv[0][0]; } if (chanPtr->flags & TCL_WRITABLE) { chanPtr->outEofChar = (int) argv[1][0]; } } if (argv != (char **) NULL) { ckfree((char *) argv); } return TCL_OK; } if ((len > 1) && (optionName[1] == 't') && (strncmp(optionName, "-translation", len) == 0)) { char *readMode, *writeMode; if (Tcl_SplitList(interp, newValue, &argc, &argv) == TCL_ERROR) { return TCL_ERROR; } if (argc == 1) { readMode = (chanPtr->flags & TCL_READABLE) ? argv[0] : NULL; writeMode = (chanPtr->flags & TCL_WRITABLE) ? argv[0] : NULL; } else if (argc == 2) { readMode = (chanPtr->flags & TCL_READABLE) ? argv[0] : NULL; writeMode = (chanPtr->flags & TCL_WRITABLE) ? argv[1] : NULL; } else { if (interp) { Tcl_AppendResult(interp, "bad value for -translation: must be a one or two", " element list", (char *) NULL); } ckfree((char *) argv); return TCL_ERROR; } if (readMode) { if (*readMode == '\0') { newMode = chanPtr->inputTranslation; } else if (strcmp(readMode, "auto") == 0) { newMode = TCL_TRANSLATE_AUTO; } else if (strcmp(readMode, "binary") == 0) { chanPtr->inEofChar = 0; newMode = TCL_TRANSLATE_LF; } else if (strcmp(readMode, "lf") == 0) { newMode = TCL_TRANSLATE_LF; } else if (strcmp(readMode, "cr") == 0) { newMode = TCL_TRANSLATE_CR; } else if (strcmp(readMode, "crlf") == 0) { newMode = TCL_TRANSLATE_CRLF; } else if (strcmp(readMode, "platform") == 0) { newMode = TCL_PLATFORM_TRANSLATION; } else { if (interp) { Tcl_AppendResult(interp, "bad value for -translation: ", "must be one of auto, binary, cr, lf, crlf,", " or platform", (char *) NULL); } ckfree((char *) argv); return TCL_ERROR; } /* * Reset the EOL flags since we need to look at any buffered * data to see if the new translation mode allows us to * complete the line. */ if (newMode != chanPtr->inputTranslation) { chanPtr->inputTranslation = (Tcl_EolTranslation) newMode; chanPtr->flags &= ~(INPUT_SAW_CR); chanPtr->flags &= ~(CHANNEL_GETS_BLOCKED); UpdateInterest(chanPtr); } } if (writeMode) { if (*writeMode == '\0') { /* Do nothing. */ } else if (strcmp(writeMode, "auto") == 0) { /* * This is a hack to get TCP sockets to produce output * in CRLF mode if they are being set into AUTO mode. * A better solution for achieving this effect will be * coded later. */ if (strcmp(chanPtr->typePtr->typeName, "tcp") == 0) { chanPtr->outputTranslation = TCL_TRANSLATE_CRLF; } else { chanPtr->outputTranslation = TCL_PLATFORM_TRANSLATION; } } else if (strcmp(writeMode, "binary") == 0) { chanPtr->outEofChar = 0; chanPtr->outputTranslation = TCL_TRANSLATE_LF; } else if (strcmp(writeMode, "lf") == 0) { chanPtr->outputTranslation = TCL_TRANSLATE_LF; } else if (strcmp(writeMode, "cr") == 0) { chanPtr->outputTranslation = TCL_TRANSLATE_CR; } else if (strcmp(writeMode, "crlf") == 0) { chanPtr->outputTranslation = TCL_TRANSLATE_CRLF; } else if (strcmp(writeMode, "platform") == 0) { chanPtr->outputTranslation = TCL_PLATFORM_TRANSLATION; } else { if (interp) { Tcl_AppendResult(interp, "bad value for -translation: ", "must be one of auto, binary, cr, lf, crlf,", " or platform", (char *) NULL); } ckfree((char *) argv); return TCL_ERROR; } } ckfree((char *) argv); return TCL_OK; } if (chanPtr->typePtr->setOptionProc != (Tcl_DriverSetOptionProc *) NULL) { return (chanPtr->typePtr->setOptionProc) (chanPtr->instanceData, interp, optionName, newValue); } return Tcl_BadChannelOption(interp, optionName, (char *) NULL); } /* *---------------------------------------------------------------------- * * CleanupChannelHandlers -- * * Removes channel handlers that refer to the supplied interpreter, * so that if the actual channel is not closed now, these handlers * will not run on subsequent events on the channel. This would be * erroneous, because the interpreter no longer has a reference to * this channel. * * Results: * None. * * Side effects: * Removes channel handlers. * *---------------------------------------------------------------------- */ static void CleanupChannelHandlers(interp, chanPtr) Tcl_Interp *interp; Channel *chanPtr; { EventScriptRecord *sPtr, *prevPtr, *nextPtr; /* * Remove fileevent records on this channel that refer to the * given interpreter. */ for (sPtr = chanPtr->scriptRecordPtr, prevPtr = (EventScriptRecord *) NULL; sPtr != (EventScriptRecord *) NULL; sPtr = nextPtr) { nextPtr = sPtr->nextPtr; if (sPtr->interp == interp) { if (prevPtr == (EventScriptRecord *) NULL) { chanPtr->scriptRecordPtr = nextPtr; } else { prevPtr->nextPtr = nextPtr; } Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, ChannelEventScriptInvoker, (ClientData) sPtr); ckfree(sPtr->script); ckfree((char *) sPtr); } else { prevPtr = sPtr; } } } /* *---------------------------------------------------------------------- * * Tcl_NotifyChannel -- * * This procedure is called by a channel driver when a driver * detects an event on a channel. This procedure is responsible * for actually handling the event by invoking any channel * handler callbacks. * * Results: * None. * * Side effects: * Whatever the channel handler callback procedure does. * *---------------------------------------------------------------------- */ void Tcl_NotifyChannel(channel, mask) Tcl_Channel channel; /* Channel that detected an event. */ int mask; /* OR'ed combination of TCL_READABLE, * TCL_WRITABLE, or TCL_EXCEPTION: indicates * which events were detected. */ { Channel *chanPtr = (Channel *) channel; ChannelHandler *chPtr; NextChannelHandler nh; /* * Preserve the channel struct in case the script closes it. */ Tcl_Preserve((ClientData) channel); /* * If we are flushing in the background, be sure to call FlushChannel * for writable events. Note that we have to discard the writable * event so we don't call any write handlers before the flush is * complete. */ if ((chanPtr->flags & BG_FLUSH_SCHEDULED) && (mask & TCL_WRITABLE)) { FlushChannel(NULL, chanPtr, 1); mask &= ~TCL_WRITABLE; } /* * Add this invocation to the list of recursive invocations of * ChannelHandlerEventProc. */ nh.nextHandlerPtr = (ChannelHandler *) NULL; nh.nestedHandlerPtr = nestedHandlerPtr; nestedHandlerPtr = &nh; for (chPtr = chanPtr->chPtr; chPtr != (ChannelHandler *) NULL; ) { /* * If this channel handler is interested in any of the events that * have occurred on the channel, invoke its procedure. */ if ((chPtr->mask & mask) != 0) { nh.nextHandlerPtr = chPtr->nextPtr; (*(chPtr->proc))(chPtr->clientData, mask); chPtr = nh.nextHandlerPtr; } else { chPtr = chPtr->nextPtr; } } /* * Update the notifier interest, since it may have changed after * invoking event handlers. */ if (chanPtr->typePtr != NULL) { UpdateInterest(chanPtr); } Tcl_Release((ClientData) channel); nestedHandlerPtr = nh.nestedHandlerPtr; } /* *---------------------------------------------------------------------- * * UpdateInterest -- * * Arrange for the notifier to call us back at appropriate times * based on the current state of the channel. * * Results: * None. * * Side effects: * May schedule a timer or driver handler. * *---------------------------------------------------------------------- */ static void UpdateInterest(chanPtr) Channel *chanPtr; /* Channel to update. */ { int mask = chanPtr->interestMask; /* * If there are flushed buffers waiting to be written, then * we need to watch for the channel to become writable. */ if (chanPtr->flags & BG_FLUSH_SCHEDULED) { mask |= TCL_WRITABLE; } /* * If there is data in the input queue, and we aren't blocked waiting for * an EOL, then we need to schedule a timer so we don't block in the * notifier. Also, cancel the read interest so we don't get duplicate * events. */ if (mask & TCL_READABLE) { if (!(chanPtr->flags & CHANNEL_GETS_BLOCKED) && (chanPtr->inQueueHead != (ChannelBuffer *) NULL) && (chanPtr->inQueueHead->nextRemoved < chanPtr->inQueueHead->nextAdded)) { mask &= ~TCL_READABLE; if (!chanPtr->timer) { chanPtr->timer = Tcl_CreateTimerHandler(0, ChannelTimerProc, (ClientData) chanPtr); } } } (chanPtr->typePtr->watchProc)(chanPtr->instanceData, mask); } /* *---------------------------------------------------------------------- * * ChannelTimerProc -- * * Timer handler scheduled by UpdateInterest to monitor the * channel buffers until they are empty. * * Results: * None. * * Side effects: * May invoke channel handlers. * *---------------------------------------------------------------------- */ static void ChannelTimerProc(clientData) ClientData clientData; { Channel *chanPtr = (Channel *) clientData; if (!(chanPtr->flags & CHANNEL_GETS_BLOCKED) && (chanPtr->interestMask & TCL_READABLE) && (chanPtr->inQueueHead != (ChannelBuffer *) NULL) && (chanPtr->inQueueHead->nextRemoved < chanPtr->inQueueHead->nextAdded)) { /* * Restart the timer in case a channel handler reenters the * event loop before UpdateInterest gets called by Tcl_NotifyChannel. */ chanPtr->timer = Tcl_CreateTimerHandler(0, ChannelTimerProc, (ClientData) chanPtr); Tcl_NotifyChannel((Tcl_Channel)chanPtr, TCL_READABLE); } else { chanPtr->timer = NULL; UpdateInterest(chanPtr); } } /* *---------------------------------------------------------------------- * * Tcl_CreateChannelHandler -- * * Arrange for a given procedure to be invoked whenever the * channel indicated by the chanPtr arg becomes readable or * writable. * * Results: * None. * * Side effects: * From now on, whenever the I/O channel given by chanPtr becomes * ready in the way indicated by mask, proc will be invoked. * See the manual entry for details on the calling sequence * to proc. If there is already an event handler for chan, proc * and clientData, then the mask will be updated. * *---------------------------------------------------------------------- */ void Tcl_CreateChannelHandler(chan, mask, proc, clientData) Tcl_Channel chan; /* The channel to create the handler for. */ int mask; /* OR'ed combination of TCL_READABLE, * TCL_WRITABLE, and TCL_EXCEPTION: * indicates conditions under which * proc should be called. Use 0 to * disable a registered handler. */ Tcl_ChannelProc *proc; /* Procedure to call for each * selected event. */ ClientData clientData; /* Arbitrary data to pass to proc. */ { ChannelHandler *chPtr; Channel *chanPtr; chanPtr = (Channel *) chan; /* * Check whether this channel handler is not already registered. If * it is not, create a new record, else reuse existing record (smash * current values). */ for (chPtr = chanPtr->chPtr; chPtr != (ChannelHandler *) NULL; chPtr = chPtr->nextPtr) { if ((chPtr->chanPtr == chanPtr) && (chPtr->proc == proc) && (chPtr->clientData == clientData)) { break; } } if (chPtr == (ChannelHandler *) NULL) { chPtr = (ChannelHandler *) ckalloc((unsigned) sizeof(ChannelHandler)); chPtr->mask = 0; chPtr->proc = proc; chPtr->clientData = clientData; chPtr->chanPtr = chanPtr; chPtr->nextPtr = chanPtr->chPtr; chanPtr->chPtr = chPtr; } /* * The remainder of the initialization below is done regardless of * whether or not this is a new record or a modification of an old * one. */ chPtr->mask = mask; /* * Recompute the interest mask for the channel - this call may actually * be disabling an existing handler. */ chanPtr->interestMask = 0; for (chPtr = chanPtr->chPtr; chPtr != (ChannelHandler *) NULL; chPtr = chPtr->nextPtr) { chanPtr->interestMask |= chPtr->mask; } UpdateInterest(chanPtr); } /* *---------------------------------------------------------------------- * * Tcl_DeleteChannelHandler -- * * Cancel a previously arranged callback arrangement for an IO * channel. * * Results: * None. * * Side effects: * If a callback was previously registered for this chan, proc and * clientData , it is removed and the callback will no longer be called * when the channel becomes ready for IO. * *---------------------------------------------------------------------- */ void Tcl_DeleteChannelHandler(chan, proc, clientData) Tcl_Channel chan; /* The channel for which to remove the * callback. */ Tcl_ChannelProc *proc; /* The procedure in the callback to delete. */ ClientData clientData; /* The client data in the callback * to delete. */ { ChannelHandler *chPtr, *prevChPtr; Channel *chanPtr; NextChannelHandler *nhPtr; chanPtr = (Channel *) chan; /* * Find the entry and the previous one in the list. */ for (prevChPtr = (ChannelHandler *) NULL, chPtr = chanPtr->chPtr; chPtr != (ChannelHandler *) NULL; chPtr = chPtr->nextPtr) { if ((chPtr->chanPtr == chanPtr) && (chPtr->clientData == clientData) && (chPtr->proc == proc)) { break; } prevChPtr = chPtr; } /* * If not found, return without doing anything. */ if (chPtr == (ChannelHandler *) NULL) { return; } /* * If ChannelHandlerEventProc is about to process this handler, tell it to * process the next one instead - we are going to delete *this* one. */ for (nhPtr = nestedHandlerPtr; nhPtr != (NextChannelHandler *) NULL; nhPtr = nhPtr->nestedHandlerPtr) { if (nhPtr->nextHandlerPtr == chPtr) { nhPtr->nextHandlerPtr = chPtr->nextPtr; } } /* * Splice it out of the list of channel handlers. */ if (prevChPtr == (ChannelHandler *) NULL) { chanPtr->chPtr = chPtr->nextPtr; } else { prevChPtr->nextPtr = chPtr->nextPtr; } ckfree((char *) chPtr); /* * Recompute the interest list for the channel, so that infinite loops * will not result if Tcl_DeleteChanelHandler is called inside an event. */ chanPtr->interestMask = 0; for (chPtr = chanPtr->chPtr; chPtr != (ChannelHandler *) NULL; chPtr = chPtr->nextPtr) { chanPtr->interestMask |= chPtr->mask; } UpdateInterest(chanPtr); } /* *---------------------------------------------------------------------- * * DeleteScriptRecord -- * * Delete a script record for this combination of channel, interp * and mask. * * Results: * None. * * Side effects: * Deletes a script record and cancels a channel event handler. * *---------------------------------------------------------------------- */ static void DeleteScriptRecord(interp, chanPtr, mask) Tcl_Interp *interp; /* Interpreter in which script was to be * executed. */ Channel *chanPtr; /* The channel for which to delete the * script record (if any). */ int mask; /* Events in mask must exactly match mask * of script to delete. */ { EventScriptRecord *esPtr, *prevEsPtr; for (esPtr = chanPtr->scriptRecordPtr, prevEsPtr = (EventScriptRecord *) NULL; esPtr != (EventScriptRecord *) NULL; prevEsPtr = esPtr, esPtr = esPtr->nextPtr) { if ((esPtr->interp == interp) && (esPtr->mask == mask)) { if (esPtr == chanPtr->scriptRecordPtr) { chanPtr->scriptRecordPtr = esPtr->nextPtr; } else { prevEsPtr->nextPtr = esPtr->nextPtr; } Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, ChannelEventScriptInvoker, (ClientData) esPtr); ckfree(esPtr->script); ckfree((char *) esPtr); break; } } } /* *---------------------------------------------------------------------- * * CreateScriptRecord -- * * Creates a record to store a script to be executed when a specific * event fires on a specific channel. * * Results: * None. * * Side effects: * Causes the script to be stored for later execution. * *---------------------------------------------------------------------- */ static void CreateScriptRecord(interp, chanPtr, mask, script) Tcl_Interp *interp; /* Interpreter in which to execute * the stored script. */ Channel *chanPtr; /* Channel for which script is to * be stored. */ int mask; /* Set of events for which script * will be invoked. */ char *script; /* A copy of this script is stored * in the newly created record. */ { EventScriptRecord *esPtr; for (esPtr = chanPtr->scriptRecordPtr; esPtr != (EventScriptRecord *) NULL; esPtr = esPtr->nextPtr) { if ((esPtr->interp == interp) && (esPtr->mask == mask)) { ckfree(esPtr->script); esPtr->script = (char *) NULL; break; } } if (esPtr == (EventScriptRecord *) NULL) { esPtr = (EventScriptRecord *) ckalloc((unsigned) sizeof(EventScriptRecord)); Tcl_CreateChannelHandler((Tcl_Channel) chanPtr, mask, ChannelEventScriptInvoker, (ClientData) esPtr); esPtr->nextPtr = chanPtr->scriptRecordPtr; chanPtr->scriptRecordPtr = esPtr; } esPtr->chanPtr = chanPtr; esPtr->interp = interp; esPtr->mask = mask; esPtr->script = ckalloc((unsigned) (strlen(script) + 1)); strcpy(esPtr->script, script); } /* *---------------------------------------------------------------------- * * ChannelEventScriptInvoker -- * * Invokes a script scheduled by "fileevent" for when the channel * becomes ready for IO. This function is invoked by the channel * handler which was created by the Tcl "fileevent" command. * * Results: * None. * * Side effects: * Whatever the script does. * *---------------------------------------------------------------------- */ static void ChannelEventScriptInvoker(clientData, mask) ClientData clientData; /* The script+interp record. */ int mask; /* Not used. */ { Tcl_Interp *interp; /* Interpreter in which to eval the script. */ Channel *chanPtr; /* The channel for which this handler is * registered. */ char *script; /* Script to eval. */ EventScriptRecord *esPtr; /* The event script + interpreter to eval it * in. */ int result; /* Result of call to eval script. */ esPtr = (EventScriptRecord *) clientData; chanPtr = esPtr->chanPtr; mask = esPtr->mask; interp = esPtr->interp; script = esPtr->script; /* * We must preserve the interpreter so we can report errors on it * later. Note that we do not need to preserve the channel because * that is done by Tcl_NotifyChannel before calling channel handlers. */ Tcl_Preserve((ClientData) interp); result = Tcl_GlobalEval(interp, script); /* * On error, cause a background error and remove the channel handler * and the script record. * * NOTE: Must delete channel handler before causing the background error * because the background error may want to reinstall the handler. */ if (result != TCL_OK) { if (chanPtr->typePtr != NULL) { DeleteScriptRecord(interp, chanPtr, mask); } Tcl_BackgroundError(interp); } Tcl_Release((ClientData) interp); } /* *---------------------------------------------------------------------- * * Tcl_FileEventCmd -- * * This procedure implements the "fileevent" Tcl command. See the * user documentation for details on what it does. This command is * based on the Tk command "fileevent" which in turn is based on work * contributed by Mark Diekhans. * * Results: * A standard Tcl result. * * Side effects: * May create a channel handler for the specified channel. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int Tcl_FileEventCmd(clientData, interp, argc, argv) ClientData clientData; /* Not used. */ Tcl_Interp *interp; /* Interpreter in which the channel * for which to create the handler * is found. */ int argc; /* Number of arguments. */ char **argv; /* Argument strings. */ { Channel *chanPtr; /* The channel to create * the handler for. */ Tcl_Channel chan; /* The opaque type for the channel. */ int c; /* First char of mode argument. */ int mask; /* Mask for events of interest. */ size_t length; /* Length of mode argument. */ /* * Parse arguments. */ if ((argc != 3) && (argc != 4)) { Tcl_AppendResult(interp, "wrong # args: must be \"", argv[0], " channelId event ?script?", (char *) NULL); return TCL_ERROR; } c = argv[2][0]; length = strlen(argv[2]); if ((c == 'r') && (strncmp(argv[2], "readable", length) == 0)) { mask = TCL_READABLE; } else if ((c == 'w') && (strncmp(argv[2], "writable", length) == 0)) { mask = TCL_WRITABLE; } else { Tcl_AppendResult(interp, "bad event name \"", argv[2], "\": must be readable or writable", (char *) NULL); return TCL_ERROR; } chan = Tcl_GetChannel(interp, argv[1], NULL); if (chan == (Tcl_Channel) NULL) { return TCL_ERROR; } chanPtr = (Channel *) chan; if ((chanPtr->flags & mask) == 0) { Tcl_AppendResult(interp, "channel is not ", (mask == TCL_READABLE) ? "readable" : "writable", (char *) NULL); return TCL_ERROR; } /* * If we are supposed to return the script, do so. */ if (argc == 3) { EventScriptRecord *esPtr; for (esPtr = chanPtr->scriptRecordPtr; esPtr != (EventScriptRecord *) NULL; esPtr = esPtr->nextPtr) { if ((esPtr->interp == interp) && (esPtr->mask == mask)) { Tcl_SetResult(interp, esPtr->script, TCL_STATIC); break; } } return TCL_OK; } /* * If we are supposed to delete a stored script, do so. */ if (argv[3][0] == 0) { DeleteScriptRecord(interp, chanPtr, mask); return TCL_OK; } /* * Make the script record that will link between the event and the * script to invoke. This also creates a channel event handler which * will evaluate the script in the supplied interpreter. */ CreateScriptRecord(interp, chanPtr, mask, argv[3]); return TCL_OK; } /* *---------------------------------------------------------------------- * * TclTestChannelCmd -- * * Implements the Tcl "testchannel" debugging command and its * subcommands. This is part of the testing environment but must be * in this file instead of tclTest.c because it needs access to the * fields of struct Channel. * * Results: * A standard Tcl result. * * Side effects: * None. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int TclTestChannelCmd(clientData, interp, argc, argv) ClientData clientData; /* Not used. */ Tcl_Interp *interp; /* Interpreter for result. */ int argc; /* Count of additional args. */ char **argv; /* Additional arg strings. */ { char *cmdName; /* Sub command. */ Tcl_HashTable *hTblPtr; /* Hash table of channels. */ Tcl_HashSearch hSearch; /* Search variable. */ Tcl_HashEntry *hPtr; /* Search variable. */ Channel *chanPtr; /* The actual channel. */ Tcl_Channel chan; /* The opaque type. */ size_t len; /* Length of subcommand string. */ int IOQueued; /* How much IO is queued inside channel? */ ChannelBuffer *bufPtr; /* For iterating over queued IO. */ char buf[128]; /* For sprintf. */ if (argc < 2) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " subcommand ?additional args..?\"", (char *) NULL); return TCL_ERROR; } cmdName = argv[1]; len = strlen(cmdName); chanPtr = (Channel *) NULL; if (argc > 2) { chan = Tcl_GetChannel(interp, argv[2], NULL); if (chan == (Tcl_Channel) NULL) { return TCL_ERROR; } chanPtr = (Channel *) chan; } if ((cmdName[0] == 'i') && (strncmp(cmdName, "info", len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " info channelName\"", (char *) NULL); return TCL_ERROR; } Tcl_AppendElement(interp, argv[2]); Tcl_AppendElement(interp, chanPtr->typePtr->typeName); if (chanPtr->flags & TCL_READABLE) { Tcl_AppendElement(interp, "read"); } else { Tcl_AppendElement(interp, ""); } if (chanPtr->flags & TCL_WRITABLE) { Tcl_AppendElement(interp, "write"); } else { Tcl_AppendElement(interp, ""); } if (chanPtr->flags & CHANNEL_NONBLOCKING) { Tcl_AppendElement(interp, "nonblocking"); } else { Tcl_AppendElement(interp, "blocking"); } if (chanPtr->flags & CHANNEL_LINEBUFFERED) { Tcl_AppendElement(interp, "line"); } else if (chanPtr->flags & CHANNEL_UNBUFFERED) { Tcl_AppendElement(interp, "none"); } else { Tcl_AppendElement(interp, "full"); } if (chanPtr->flags & BG_FLUSH_SCHEDULED) { Tcl_AppendElement(interp, "async_flush"); } else { Tcl_AppendElement(interp, ""); } if (chanPtr->flags & CHANNEL_EOF) { Tcl_AppendElement(interp, "eof"); } else { Tcl_AppendElement(interp, ""); } if (chanPtr->flags & CHANNEL_BLOCKED) { Tcl_AppendElement(interp, "blocked"); } else { Tcl_AppendElement(interp, "unblocked"); } if (chanPtr->inputTranslation == TCL_TRANSLATE_AUTO) { Tcl_AppendElement(interp, "auto"); if (chanPtr->flags & INPUT_SAW_CR) { Tcl_AppendElement(interp, "saw_cr"); } else { Tcl_AppendElement(interp, ""); } } else if (chanPtr->inputTranslation == TCL_TRANSLATE_LF) { Tcl_AppendElement(interp, "lf"); Tcl_AppendElement(interp, ""); } else if (chanPtr->inputTranslation == TCL_TRANSLATE_CR) { Tcl_AppendElement(interp, "cr"); Tcl_AppendElement(interp, ""); } else if (chanPtr->inputTranslation == TCL_TRANSLATE_CRLF) { Tcl_AppendElement(interp, "crlf"); if (chanPtr->flags & INPUT_SAW_CR) { Tcl_AppendElement(interp, "queued_cr"); } else { Tcl_AppendElement(interp, ""); } } if (chanPtr->outputTranslation == TCL_TRANSLATE_AUTO) { Tcl_AppendElement(interp, "auto"); } else if (chanPtr->outputTranslation == TCL_TRANSLATE_LF) { Tcl_AppendElement(interp, "lf"); } else if (chanPtr->outputTranslation == TCL_TRANSLATE_CR) { Tcl_AppendElement(interp, "cr"); } else if (chanPtr->outputTranslation == TCL_TRANSLATE_CRLF) { Tcl_AppendElement(interp, "crlf"); } for (IOQueued = 0, bufPtr = chanPtr->inQueueHead; bufPtr != (ChannelBuffer *) NULL; bufPtr = bufPtr->nextPtr) { IOQueued += bufPtr->nextAdded - bufPtr->nextRemoved; } TclFormatInt(buf, IOQueued); Tcl_AppendElement(interp, buf); IOQueued = 0; if (chanPtr->curOutPtr != (ChannelBuffer *) NULL) { IOQueued = chanPtr->curOutPtr->nextAdded - chanPtr->curOutPtr->nextRemoved; } for (bufPtr = chanPtr->outQueueHead; bufPtr != (ChannelBuffer *) NULL; bufPtr = bufPtr->nextPtr) { IOQueued += (bufPtr->nextAdded - bufPtr->nextRemoved); } TclFormatInt(buf, IOQueued); Tcl_AppendElement(interp, buf); TclFormatInt(buf, Tcl_Tell((Tcl_Channel) chanPtr)); Tcl_AppendElement(interp, buf); TclFormatInt(buf, chanPtr->refCount); Tcl_AppendElement(interp, buf); return TCL_OK; } if ((cmdName[0] == 'i') && (strncmp(cmdName, "inputbuffered", len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "channel name required", (char *) NULL); return TCL_ERROR; } for (IOQueued = 0, bufPtr = chanPtr->inQueueHead; bufPtr != (ChannelBuffer *) NULL; bufPtr = bufPtr->nextPtr) { IOQueued += bufPtr->nextAdded - bufPtr->nextRemoved; } sprintf(buf, "%d", IOQueued); Tcl_AppendResult(interp, buf, (char *) NULL); return TCL_OK; } if ((cmdName[0] == 'm') && (strncmp(cmdName, "mode", len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "channel name required", (char *) NULL); return TCL_ERROR; } if (chanPtr->flags & TCL_READABLE) { Tcl_AppendElement(interp, "read"); } else { Tcl_AppendElement(interp, ""); } if (chanPtr->flags & TCL_WRITABLE) { Tcl_AppendElement(interp, "write"); } else { Tcl_AppendElement(interp, ""); } return TCL_OK; } if ((cmdName[0] == 'n') && (strncmp(cmdName, "name", len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "channel name required", (char *) NULL); return TCL_ERROR; } Tcl_AppendResult(interp, chanPtr->channelName, (char *) NULL); return TCL_OK; } if ((cmdName[0] == 'o') && (strncmp(cmdName, "open", len) == 0)) { hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); if (hTblPtr == (Tcl_HashTable *) NULL) { return TCL_OK; } for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); hPtr != (Tcl_HashEntry *) NULL; hPtr = Tcl_NextHashEntry(&hSearch)) { Tcl_AppendElement(interp, Tcl_GetHashKey(hTblPtr, hPtr)); } return TCL_OK; } if ((cmdName[0] == 'o') && (strncmp(cmdName, "outputbuffered", len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "channel name required", (char *) NULL); return TCL_ERROR; } IOQueued = 0; if (chanPtr->curOutPtr != (ChannelBuffer *) NULL) { IOQueued = chanPtr->curOutPtr->nextAdded - chanPtr->curOutPtr->nextRemoved; } for (bufPtr = chanPtr->outQueueHead; bufPtr != (ChannelBuffer *) NULL; bufPtr = bufPtr->nextPtr) { IOQueued += (bufPtr->nextAdded - bufPtr->nextRemoved); } sprintf(buf, "%d", IOQueued); Tcl_AppendResult(interp, buf, (char *) NULL); return TCL_OK; } if ((cmdName[0] == 'q') && (strncmp(cmdName, "queuedcr", len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "channel name required", (char *) NULL); return TCL_ERROR; } Tcl_AppendResult(interp, (chanPtr->flags & INPUT_SAW_CR) ? "1" : "0", (char *) NULL); return TCL_OK; } if ((cmdName[0] == 'r') && (strncmp(cmdName, "readable", len) == 0)) { hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); if (hTblPtr == (Tcl_HashTable *) NULL) { return TCL_OK; } for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); hPtr != (Tcl_HashEntry *) NULL; hPtr = Tcl_NextHashEntry(&hSearch)) { chanPtr = (Channel *) Tcl_GetHashValue(hPtr); if (chanPtr->flags & TCL_READABLE) { Tcl_AppendElement(interp, Tcl_GetHashKey(hTblPtr, hPtr)); } } return TCL_OK; } if ((cmdName[0] == 'r') && (strncmp(cmdName, "refcount", len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "channel name required", (char *) NULL); return TCL_ERROR; } sprintf(buf, "%d", chanPtr->refCount); Tcl_AppendResult(interp, buf, (char *) NULL); return TCL_OK; } if ((cmdName[0] == 't') && (strncmp(cmdName, "type", len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "channel name required", (char *) NULL); return TCL_ERROR; } Tcl_AppendResult(interp, chanPtr->typePtr->typeName, (char *) NULL); return TCL_OK; } if ((cmdName[0] == 'w') && (strncmp(cmdName, "writable", len) == 0)) { hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclIO", NULL); if (hTblPtr == (Tcl_HashTable *) NULL) { return TCL_OK; } for (hPtr = Tcl_FirstHashEntry(hTblPtr, &hSearch); hPtr != (Tcl_HashEntry *) NULL; hPtr = Tcl_NextHashEntry(&hSearch)) { chanPtr = (Channel *) Tcl_GetHashValue(hPtr); if (chanPtr->flags & TCL_WRITABLE) { Tcl_AppendElement(interp, Tcl_GetHashKey(hTblPtr, hPtr)); } } return TCL_OK; } Tcl_AppendResult(interp, "bad option \"", cmdName, "\": should be ", "info, open, readable, or writable", (char *) NULL); return TCL_ERROR; } /* *---------------------------------------------------------------------- * * TclTestChannelEventCmd -- * * This procedure implements the "testchannelevent" command. It is * used to test the Tcl channel event mechanism. It is present in * this file instead of tclTest.c because it needs access to the * internal structure of the channel. * * Results: * A standard Tcl result. * * Side effects: * Creates, deletes and returns channel event handlers. * *---------------------------------------------------------------------- */ /* ARGSUSED */ int TclTestChannelEventCmd(dummy, interp, argc, argv) ClientData dummy; /* Not used. */ Tcl_Interp *interp; /* Current interpreter. */ int argc; /* Number of arguments. */ char **argv; /* Argument strings. */ { Channel *chanPtr; EventScriptRecord *esPtr, *prevEsPtr, *nextEsPtr; char *cmd; int index, i, mask, len; if ((argc < 3) || (argc > 5)) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " channelName cmd ?arg1? ?arg2?\"", (char *) NULL); return TCL_ERROR; } chanPtr = (Channel *) Tcl_GetChannel(interp, argv[1], NULL); if (chanPtr == (Channel *) NULL) { return TCL_ERROR; } cmd = argv[2]; len = strlen(cmd); if ((cmd[0] == 'a') && (strncmp(cmd, "add", (unsigned) len) == 0)) { if (argc != 5) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " channelName add eventSpec script\"", (char *) NULL); return TCL_ERROR; } if (strcmp(argv[3], "readable") == 0) { mask = TCL_READABLE; } else if (strcmp(argv[3], "writable") == 0) { mask = TCL_WRITABLE; } else if (strcmp(argv[3], "none") == 0) { mask = 0; } else { Tcl_AppendResult(interp, "bad event name \"", argv[3], "\": must be readable, writable, or none", (char *) NULL); return TCL_ERROR; } esPtr = (EventScriptRecord *) ckalloc((unsigned) sizeof(EventScriptRecord)); esPtr->nextPtr = chanPtr->scriptRecordPtr; chanPtr->scriptRecordPtr = esPtr; esPtr->chanPtr = chanPtr; esPtr->interp = interp; esPtr->mask = mask; esPtr->script = ckalloc((unsigned) (strlen(argv[4]) + 1)); strcpy(esPtr->script, argv[4]); Tcl_CreateChannelHandler((Tcl_Channel) chanPtr, mask, ChannelEventScriptInvoker, (ClientData) esPtr); return TCL_OK; } if ((cmd[0] == 'd') && (strncmp(cmd, "delete", (unsigned) len) == 0)) { if (argc != 4) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " channelName delete index\"", (char *) NULL); return TCL_ERROR; } if (Tcl_GetInt(interp, argv[3], &index) == TCL_ERROR) { return TCL_ERROR; } if (index < 0) { Tcl_AppendResult(interp, "bad event index: ", argv[3], ": must be nonnegative", (char *) NULL); return TCL_ERROR; } for (i = 0, esPtr = chanPtr->scriptRecordPtr; (i < index) && (esPtr != (EventScriptRecord *) NULL); i++, esPtr = esPtr->nextPtr) { /* Empty loop body. */ } if (esPtr == (EventScriptRecord *) NULL) { Tcl_AppendResult(interp, "bad event index ", argv[3], ": out of range", (char *) NULL); return TCL_ERROR; } if (esPtr == chanPtr->scriptRecordPtr) { chanPtr->scriptRecordPtr = esPtr->nextPtr; } else { for (prevEsPtr = chanPtr->scriptRecordPtr; (prevEsPtr != (EventScriptRecord *) NULL) && (prevEsPtr->nextPtr != esPtr); prevEsPtr = prevEsPtr->nextPtr) { /* Empty loop body. */ } if (prevEsPtr == (EventScriptRecord *) NULL) { panic("TclTestChannelEventCmd: damaged event script list"); } prevEsPtr->nextPtr = esPtr->nextPtr; } Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, ChannelEventScriptInvoker, (ClientData) esPtr); ckfree(esPtr->script); ckfree((char *) esPtr); return TCL_OK; } if ((cmd[0] == 'l') && (strncmp(cmd, "list", (unsigned) len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " channelName list\"", (char *) NULL); return TCL_ERROR; } for (esPtr = chanPtr->scriptRecordPtr; esPtr != (EventScriptRecord *) NULL; esPtr = esPtr->nextPtr) { char *event; if (esPtr->mask) { event = ((esPtr->mask == TCL_READABLE) ? "readable" : "writable"); } else { event = "none"; } Tcl_AppendElement(interp, event); Tcl_AppendElement(interp, esPtr->script); } return TCL_OK; } if ((cmd[0] == 'r') && (strncmp(cmd, "removeall", (unsigned) len) == 0)) { if (argc != 3) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " channelName removeall\"", (char *) NULL); return TCL_ERROR; } for (esPtr = chanPtr->scriptRecordPtr; esPtr != (EventScriptRecord *) NULL; esPtr = nextEsPtr) { nextEsPtr = esPtr->nextPtr; Tcl_DeleteChannelHandler((Tcl_Channel) chanPtr, ChannelEventScriptInvoker, (ClientData) esPtr); ckfree(esPtr->script); ckfree((char *) esPtr); } chanPtr->scriptRecordPtr = (EventScriptRecord *) NULL; return TCL_OK; } if ((cmd[0] == 's') && (strncmp(cmd, "set", (unsigned) len) == 0)) { if (argc != 5) { Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0], " channelName delete index event\"", (char *) NULL); return TCL_ERROR; } if (Tcl_GetInt(interp, argv[3], &index) == TCL_ERROR) { return TCL_ERROR; } if (index < 0) { Tcl_AppendResult(interp, "bad event index: ", argv[3], ": must be nonnegative", (char *) NULL); return TCL_ERROR; } for (i = 0, esPtr = chanPtr->scriptRecordPtr; (i < index) && (esPtr != (EventScriptRecord *) NULL); i++, esPtr = esPtr->nextPtr) { /* Empty loop body. */ } if (esPtr == (EventScriptRecord *) NULL) { Tcl_AppendResult(interp, "bad event index ", argv[3], ": out of range", (char *) NULL); return TCL_ERROR; } if (strcmp(argv[4], "readable") == 0) { mask = TCL_READABLE; } else if (strcmp(argv[4], "writable") == 0) { mask = TCL_WRITABLE; } else if (strcmp(argv[4], "none") == 0) { mask = 0; } else { Tcl_AppendResult(interp, "bad event name \"", argv[4], "\": must be readable, writable, or none", (char *) NULL); return TCL_ERROR; } esPtr->mask = mask; Tcl_CreateChannelHandler((Tcl_Channel) chanPtr, mask, ChannelEventScriptInvoker, (ClientData) esPtr); return TCL_OK; } Tcl_AppendResult(interp, "bad command ", cmd, ", must be one of ", "add, delete, list, set, or removeall", (char *) NULL); return TCL_ERROR; } /* *---------------------------------------------------------------------- * * TclCopyChannel -- * * This routine copies data from one channel to another, either * synchronously or asynchronously. If a command script is * supplied, the operation runs in the background. The script * is invoked when the copy completes. Otherwise the function * waits until the copy is completed before returning. * * Results: * A standard Tcl result. * * Side effects: * May schedule a background copy operation that causes both * channels to be marked busy. * *---------------------------------------------------------------------- */ int TclCopyChannel(interp, inChan, outChan, toRead, cmdPtr) Tcl_Interp *interp; /* Current interpreter. */ Tcl_Channel inChan; /* Channel to read from. */ Tcl_Channel outChan; /* Channel to write to. */ int toRead; /* Amount of data to copy, or -1 for all. */ Tcl_Obj *cmdPtr; /* Pointer to script to execute or NULL. */ { Channel *inPtr = (Channel *) inChan; Channel *outPtr = (Channel *) outChan; int readFlags, writeFlags; CopyState *csPtr; int nonBlocking = (cmdPtr) ? CHANNEL_NONBLOCKING : 0; if (inPtr->csPtr) { Tcl_AppendStringsToObj(Tcl_GetObjResult(interp), "channel \"", Tcl_GetChannelName(inChan), "\" is busy", NULL); return TCL_ERROR; } if (outPtr->csPtr) { Tcl_AppendStringsToObj(Tcl_GetObjResult(interp), "channel \"", Tcl_GetChannelName(outChan), "\" is busy", NULL); return TCL_ERROR; } readFlags = inPtr->flags; writeFlags = outPtr->flags; /* * Set up the blocking mode appropriately. Background copies need * non-blocking channels. Foreground copies need blocking channels. * If there is an error, restore the old blocking mode. */ if (nonBlocking != (readFlags & CHANNEL_NONBLOCKING)) { if (SetBlockMode(interp, inPtr, nonBlocking ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING) != TCL_OK) { return TCL_ERROR; } } if (inPtr != outPtr) { if (nonBlocking != (writeFlags & CHANNEL_NONBLOCKING)) { if (SetBlockMode(NULL, outPtr, nonBlocking ? TCL_MODE_BLOCKING : TCL_MODE_NONBLOCKING) != TCL_OK) { if (nonBlocking != (readFlags & CHANNEL_NONBLOCKING)) { SetBlockMode(NULL, inPtr, (readFlags & CHANNEL_NONBLOCKING) ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING); return TCL_ERROR; } } } } /* * Make sure the output side is unbuffered. */ outPtr->flags = (outPtr->flags & ~(CHANNEL_LINEBUFFERED)) | CHANNEL_UNBUFFERED; /* * Allocate a new CopyState to maintain info about the current copy in * progress. This structure will be deallocated when the copy is * completed. */ csPtr = (CopyState*) ckalloc(sizeof(CopyState) + inPtr->bufSize); csPtr->bufSize = inPtr->bufSize; csPtr->readPtr = inPtr; csPtr->writePtr = outPtr; csPtr->readFlags = readFlags; csPtr->writeFlags = writeFlags; csPtr->toRead = toRead; csPtr->total = 0; csPtr->interp = interp; if (cmdPtr) { Tcl_IncrRefCount(cmdPtr); } csPtr->cmdPtr = cmdPtr; inPtr->csPtr = csPtr; outPtr->csPtr = csPtr; /* * Start copying data between the channels. */ return CopyData(csPtr, 0); } /* *---------------------------------------------------------------------- * * CopyData -- * * This function implements the lowest level of the copying * mechanism for TclCopyChannel. * * Results: * Returns TCL_OK on success, else TCL_ERROR. * * Side effects: * Moves data between channels, may create channel handlers. * *---------------------------------------------------------------------- */ static int CopyData(csPtr, mask) CopyState *csPtr; /* State of copy operation. */ int mask; /* Current channel event flags. */ { Tcl_Interp *interp; Tcl_Obj *cmdPtr, *errObj = NULL; Tcl_Channel inChan, outChan; int result = TCL_OK; int size; int total; inChan = (Tcl_Channel)csPtr->readPtr; outChan = (Tcl_Channel)csPtr->writePtr; interp = csPtr->interp; cmdPtr = csPtr->cmdPtr; /* * Copy the data the slow way, using the translation mechanism. */ while (csPtr->toRead != 0) { /* * Check for unreported background errors. */ if (csPtr->readPtr->unreportedError != 0) { Tcl_SetErrno(csPtr->readPtr->unreportedError); csPtr->readPtr->unreportedError = 0; goto readError; } if (csPtr->writePtr->unreportedError != 0) { Tcl_SetErrno(csPtr->writePtr->unreportedError); csPtr->writePtr->unreportedError = 0; goto writeError; } /* * Read up to bufSize bytes. */ if ((csPtr->toRead == -1) || (csPtr->toRead > csPtr->bufSize)) { size = csPtr->bufSize; } else { size = csPtr->toRead; } size = DoRead(csPtr->readPtr, csPtr->buffer, size); if (size < 0) { readError: errObj = Tcl_NewObj(); Tcl_AppendStringsToObj(errObj, "error reading \"", Tcl_GetChannelName(inChan), "\": ", Tcl_PosixError(interp), (char *) NULL); break; } else if (size == 0) { /* * We had an underflow on the read side. If we are at EOF, * then the copying is done, otherwise set up a channel * handler to detect when the channel becomes readable again. */ if (Tcl_Eof(inChan)) { break; } else if (!(mask & TCL_READABLE)) { if (mask & TCL_WRITABLE) { Tcl_DeleteChannelHandler(outChan, CopyEventProc, (ClientData) csPtr); } Tcl_CreateChannelHandler(inChan, TCL_READABLE, CopyEventProc, (ClientData) csPtr); } return TCL_OK; } /* * Now write the buffer out. */ size = DoWrite(csPtr->writePtr, csPtr->buffer, size); if (size < 0) { writeError: errObj = Tcl_NewObj(); Tcl_AppendStringsToObj(errObj, "error writing \"", Tcl_GetChannelName(outChan), "\": ", Tcl_PosixError(interp), (char *) NULL); break; } /* * Check to see if the write is happening in the background. If so, * stop copying and wait for the channel to become writable again. */ if (csPtr->writePtr->flags & BG_FLUSH_SCHEDULED) { if (!(mask & TCL_WRITABLE)) { if (mask & TCL_READABLE) { Tcl_DeleteChannelHandler(outChan, CopyEventProc, (ClientData) csPtr); } Tcl_CreateChannelHandler(outChan, TCL_WRITABLE, CopyEventProc, (ClientData) csPtr); } return TCL_OK; } /* * Update the current byte count if we care. */ if (csPtr->toRead != -1) { csPtr->toRead -= size; } csPtr->total += size; /* * For background copies, we only do one buffer per invocation so * we don't starve the rest of the system. */ if (cmdPtr) { /* * The first time we enter this code, there won't be a * channel handler established yet, so do it here. */ if (mask == 0) { Tcl_CreateChannelHandler(outChan, TCL_WRITABLE, CopyEventProc, (ClientData) csPtr); } return TCL_OK; } } /* * Make the callback or return the number of bytes transferred. * The local total is used because StopCopy frees csPtr. */ total = csPtr->total; if (cmdPtr) { /* * Get a private copy of the command so we can mutate it * by adding arguments. Note that StopCopy frees our saved * reference to the original command obj. */ cmdPtr = Tcl_DuplicateObj(cmdPtr); Tcl_IncrRefCount(cmdPtr); StopCopy(csPtr); Tcl_Preserve((ClientData) interp); Tcl_ListObjAppendElement(interp, cmdPtr, Tcl_NewIntObj(total)); if (errObj) { Tcl_ListObjAppendElement(interp, cmdPtr, errObj); } if (Tcl_GlobalEvalObj(interp, cmdPtr) != TCL_OK) { Tcl_BackgroundError(interp); result = TCL_ERROR; } Tcl_DecrRefCount(cmdPtr); Tcl_Release((ClientData) interp); } else { StopCopy(csPtr); if (errObj) { Tcl_SetObjResult(interp, errObj); result = TCL_ERROR; } else { Tcl_ResetResult(interp); Tcl_SetIntObj(Tcl_GetObjResult(interp), total); } } return result; } /* *---------------------------------------------------------------------- * * CopyEventProc -- * * This routine is invoked as a channel event handler for * the background copy operation. It is just a trivial wrapper * around the CopyData routine. * * Results: * None. * * Side effects: * None. * *---------------------------------------------------------------------- */ static void CopyEventProc(clientData, mask) ClientData clientData; int mask; { (void) CopyData((CopyState *)clientData, mask); } /* *---------------------------------------------------------------------- * * StopCopy -- * * This routine halts a copy that is in progress. * * Results: * None. * * Side effects: * Removes any pending channel handlers and restores the blocking * and buffering modes of the channels. The CopyState is freed. * *---------------------------------------------------------------------- */ static void StopCopy(csPtr) CopyState *csPtr; /* State for bg copy to stop . */ { int nonBlocking; if (!csPtr) { return; } /* * Restore the old blocking mode and output buffering mode. */ nonBlocking = (csPtr->readFlags & CHANNEL_NONBLOCKING); if (nonBlocking != (csPtr->readPtr->flags & CHANNEL_NONBLOCKING)) { SetBlockMode(NULL, csPtr->readPtr, nonBlocking ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING); } if (csPtr->writePtr != csPtr->writePtr) { if (nonBlocking != (csPtr->writePtr->flags & CHANNEL_NONBLOCKING)) { SetBlockMode(NULL, csPtr->writePtr, nonBlocking ? TCL_MODE_NONBLOCKING : TCL_MODE_BLOCKING); } } csPtr->writePtr->flags &= ~(CHANNEL_LINEBUFFERED | CHANNEL_UNBUFFERED); csPtr->writePtr->flags |= csPtr->writeFlags & (CHANNEL_LINEBUFFERED | CHANNEL_UNBUFFERED); if (csPtr->cmdPtr) { Tcl_DeleteChannelHandler((Tcl_Channel)csPtr->readPtr, CopyEventProc, (ClientData)csPtr); if (csPtr->readPtr != csPtr->writePtr) { Tcl_DeleteChannelHandler((Tcl_Channel)csPtr->writePtr, CopyEventProc, (ClientData)csPtr); } Tcl_DecrRefCount(csPtr->cmdPtr); } csPtr->readPtr->csPtr = NULL; csPtr->writePtr->csPtr = NULL; ckfree((char*) csPtr); }