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Diffstat (limited to 'tcl/generic/tclIO.c')
| -rw-r--r-- | tcl/generic/tclIO.c | 6053 |
1 files changed, 6053 insertions, 0 deletions
diff --git a/tcl/generic/tclIO.c b/tcl/generic/tclIO.c new file mode 100644 index 00000000000..f3e080e7189 --- /dev/null +++ b/tcl/generic/tclIO.c @@ -0,0 +1,6053 @@ +/* + * 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: @(#) $Id$ + */ + +#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); +} |