diff options
Diffstat (limited to 'generic/tclIO.c')
| -rw-r--r-- | generic/tclIO.c | 2679 |
1 files changed, 1453 insertions, 1226 deletions
diff --git a/generic/tclIO.c b/generic/tclIO.c index 011dd38..5a871be 100644 --- a/generic/tclIO.c +++ b/generic/tclIO.c @@ -6,6 +6,7 @@ * * Copyright (c) 1998-2000 Ajuba Solutions * Copyright (c) 1995-1997 Sun Microsystems, Inc. + * Contributions from Don Porter, NIST, 2014. (not subject to US copyright) * * See the file "license.terms" for information on usage and redistribution of * this file, and for a DISCLAIMER OF ALL WARRANTIES. @@ -34,15 +35,15 @@ typedef struct ChannelHandler { /* * This structure keeps track of the current ChannelHandler being invoked in - * the current invocation of ChannelHandlerEventProc. There is a potential + * the current invocation of Tcl_NotifyChannel. 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 + * Tcl_NotifyChannel 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 + * The nestedHandlerPtr field is used to chain together all recursive + * invocations, so that Tcl_DeleteChannelHandler can find all the recursively + * nested invocations of Tcl_NotifyChannel 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. @@ -53,21 +54,10 @@ typedef struct NextChannelHandler { * this invocation. */ struct NextChannelHandler *nestedHandlerPtr; /* Next nested invocation of - * ChannelHandlerEventProc. */ + * Tcl_NotifyChannel. */ } NextChannelHandler; /* - * The following structure describes the event that is added to the Tcl - * event queue by the channel handler check procedure. - */ - -typedef struct ChannelHandlerEvent { - Tcl_Event header; /* Standard header for all events. */ - Channel *chanPtr; /* The channel that is ready. */ - int readyMask; /* Events that have occurred. */ -} ChannelHandlerEvent; - -/* * The following structure is used by Tcl_GetsObj() to encapsulates the * state for a "gets" operation. */ @@ -129,7 +119,7 @@ typedef struct CopyState { typedef struct { NextChannelHandler *nestedHandlerPtr; /* This variable holds the list of nested - * ChannelHandlerEventProc invocations. */ + * Tcl_NotifyChannel invocations. */ ChannelState *firstCSPtr; /* List of all channels currently open, * indexed by ChannelState, as only one * ChannelState exists per set of stacked @@ -165,7 +155,9 @@ static ChannelBuffer * AllocChannelBuffer(int length); static void PreserveChannelBuffer(ChannelBuffer *bufPtr); static void ReleaseChannelBuffer(ChannelBuffer *bufPtr); static int IsShared(ChannelBuffer *bufPtr); +static void ChannelFree(Channel *chanPtr); static void ChannelTimerProc(ClientData clientData); +static int ChanRead(Channel *chanPtr, char *dst, int dstSize); static int CheckChannelErrors(ChannelState *statePtr, int direction); static int CheckForDeadChannel(Tcl_Interp *interp, @@ -179,10 +171,15 @@ static int CloseChannelPart(Tcl_Interp *interp, Channel *chanPtr, int errorCode, int flags); static int CloseWrite(Tcl_Interp *interp, Channel *chanPtr); static void CommonGetsCleanup(Channel *chanPtr); -static int CopyAndTranslateBuffer(ChannelState *statePtr, - char *result, int space); -static int CopyBuffer(Channel *chanPtr, char *result, int space); static int CopyData(CopyState *csPtr, int mask); +static int MoveBytes(CopyState *csPtr); + +static void MBCallback(CopyState *csPtr, Tcl_Obj *errObj); +static void MBError(CopyState *csPtr, int mask, int errorCode); +static int MBRead(CopyState *csPtr); +static int MBWrite(CopyState *csPtr); +static void MBEvent(ClientData clientData, int mask); + static void CopyEventProc(ClientData clientData, int mask); static void CreateScriptRecord(Tcl_Interp *interp, Channel *chanPtr, int mask, Tcl_Obj *scriptPtr); @@ -194,7 +191,8 @@ static int DetachChannel(Tcl_Interp *interp, Tcl_Channel chan); static void DiscardInputQueued(ChannelState *statePtr, int discardSavedBuffers); static void DiscardOutputQueued(ChannelState *chanPtr); -static int DoRead(Channel *chanPtr, char *srcPtr, int slen, int allowShortReads); +static int DoRead(Channel *chanPtr, char *dst, int bytesToRead, + int allowShortReads); static int DoReadChars(Channel *chan, Tcl_Obj *objPtr, int toRead, int appendFlag); static int FilterInputBytes(Channel *chanPtr, @@ -211,16 +209,16 @@ static int HaveVersion(const Tcl_ChannelType *typePtr, static void PeekAhead(Channel *chanPtr, char **dstEndPtr, GetsState *gsPtr); static int ReadBytes(ChannelState *statePtr, Tcl_Obj *objPtr, - int charsLeft, int *offsetPtr); + int charsLeft); static int ReadChars(ChannelState *statePtr, Tcl_Obj *objPtr, - int charsLeft, int *offsetPtr, int *factorPtr); + int charsLeft, int *factorPtr); static void RecycleBuffer(ChannelState *statePtr, ChannelBuffer *bufPtr, int mustDiscard); static int StackSetBlockMode(Channel *chanPtr, int mode); static int SetBlockMode(Tcl_Interp *interp, Channel *chanPtr, int mode); static void StopCopy(CopyState *csPtr); -static int TranslateInputEOL(ChannelState *statePtr, char *dst, +static void TranslateInputEOL(ChannelState *statePtr, char *dst, const char *src, int *dstLenPtr, int *srcLenPtr); static void UpdateInterest(Channel *chanPtr); static int Write(Channel *chanPtr, const char *src, @@ -287,7 +285,7 @@ static int WillRead(Channel *chanPtr); #define IsBufferEmpty(bufPtr) ((bufPtr)->nextAdded == (bufPtr)->nextRemoved) -#define IsBufferFull(bufPtr) ((bufPtr)->nextAdded >= (bufPtr)->bufLength) +#define IsBufferFull(bufPtr) ((bufPtr) && (bufPtr)->nextAdded >= (bufPtr)->bufLength) #define IsBufferOverflowing(bufPtr) ((bufPtr)->nextAdded>(bufPtr)->bufLength) @@ -382,20 +380,87 @@ ChanCloseHalf( return chanPtr->typePtr->close2Proc(chanPtr->instanceData, interp, flags); } -static inline int +/* + *--------------------------------------------------------------------------- + * + * ChanRead -- + * + * Read up to dstSize bytes using the inputProc of chanPtr, store + * them at dst, and return the number of bytes stored. + * + * Results: + * The return value of the driver inputProc, + * - number of bytes stored at dst, ot + * - -1 on error, with a Posix error code available to the + * caller by calling Tcl_GetErrno(). + * + * Side effects: + * The CHANNEL_BLOCKED and CHANNEL_EOF flags of the channel state are + * set as appropriate. + * On EOF, the inputEncodingFlags are set to perform ending operations + * on decoding. + * TODO - Is this really the right place for that? + * + *--------------------------------------------------------------------------- + */ +static int ChanRead( Channel *chanPtr, char *dst, - int dstSize, - int *errnoPtr) + int dstSize) { + int bytesRead, result; + + /* + * If the caller asked for zero bytes, we'd force the inputProc + * to return zero bytes, and then misinterpret that as EOF. + */ + assert(dstSize > 0); + + /* + * Each read op must set the blocked and eof states anew, not let + * the effect of prior reads leak through. + */ + if (GotFlag(chanPtr->state, CHANNEL_EOF)) { + chanPtr->state->inputEncodingFlags |= TCL_ENCODING_START; + } + ResetFlag(chanPtr->state, CHANNEL_BLOCKED | CHANNEL_EOF); + chanPtr->state->inputEncodingFlags &= ~TCL_ENCODING_END; if (WillRead(chanPtr) < 0) { - *errnoPtr = Tcl_GetErrno(); return -1; } - return chanPtr->typePtr->inputProc(chanPtr->instanceData, dst, dstSize, - errnoPtr); + bytesRead = chanPtr->typePtr->inputProc(chanPtr->instanceData, + dst, dstSize, &result); + + /* Stop any flag leakage through stacked channel levels */ + if (GotFlag(chanPtr->state, CHANNEL_EOF)) { + chanPtr->state->inputEncodingFlags |= TCL_ENCODING_START; + } + ResetFlag(chanPtr->state, CHANNEL_BLOCKED | CHANNEL_EOF); + chanPtr->state->inputEncodingFlags &= ~TCL_ENCODING_END; + if (bytesRead > 0) { + /* + * 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 (bytesRead < dstSize) { + SetFlag(chanPtr->state, CHANNEL_BLOCKED); + } + } else if (bytesRead == 0) { + SetFlag(chanPtr->state, CHANNEL_EOF); + chanPtr->state->inputEncodingFlags |= TCL_ENCODING_END; + } else if (bytesRead < 0) { + if ((result == EWOULDBLOCK) || (result == EAGAIN)) { + SetFlag(chanPtr->state, CHANNEL_BLOCKED); + result = EAGAIN; + } + Tcl_SetErrno(result); + } + return bytesRead; } static inline Tcl_WideInt @@ -559,6 +624,7 @@ TclFinalizeIOSubsystem(void) if (active) { + TclChannelPreserve((Tcl_Channel)chanPtr); /* * TIP #398: by default, we no longer set the channel back into * blocking mode. To restore the old blocking behavior, the @@ -617,6 +683,7 @@ TclFinalizeIOSubsystem(void) chanPtr->instanceData = NULL; SetFlag(statePtr, CHANNEL_DEAD); } + TclChannelRelease((Tcl_Channel)chanPtr); } } @@ -1178,15 +1245,6 @@ Tcl_UnregisterChannel( */ if (statePtr->refCount <= 0) { - /* - * Ensure that if there is another buffer, it gets flushed whether or - * not we are doing a background flush. - */ - - if ((statePtr->curOutPtr != NULL) && - IsBufferReady(statePtr->curOutPtr)) { - SetFlag(statePtr, BUFFER_READY); - } Tcl_Preserve(statePtr); if (!GotFlag(statePtr, BG_FLUSH_SCHEDULED)) { /* @@ -1498,6 +1556,22 @@ Tcl_CreateChannel( */ assert(sizeof(Tcl_ChannelTypeVersion) == sizeof(Tcl_DriverBlockModeProc *)); + assert(typePtr->typeName != NULL); + if (NULL == typePtr->closeProc) { + Tcl_Panic("channel type %s must define closeProc", typePtr->typeName); + } + if ((TCL_READABLE & mask) && (NULL == typePtr->inputProc)) { + Tcl_Panic("channel type %s must define inputProc when used for reader channel", typePtr->typeName); + } + if ((TCL_WRITABLE & mask) && (NULL == typePtr->outputProc)) { + Tcl_Panic("channel type %s must define outputProc when used for writer channel", typePtr->typeName); + } + if (NULL == typePtr->watchProc) { + Tcl_Panic("channel type %s must define watchProc", typePtr->typeName); + } + if ((NULL!=typePtr->wideSeekProc) && (NULL == typePtr->seekProc)) { + Tcl_Panic("channel type %s must define seekProc if defining wideSeekProc", typePtr->typeName); + } /* * JH: We could subsequently memset these to 0 to avoid the numerous @@ -1594,6 +1668,7 @@ Tcl_CreateChannel( chanPtr->upChanPtr = NULL; chanPtr->inQueueHead = NULL; chanPtr->inQueueTail = NULL; + chanPtr->refCount = 0; /* * TIP #219, Tcl Channel Reflection API @@ -1747,6 +1822,10 @@ Tcl_StackChannel( statePtr->csPtrR = NULL; statePtr->csPtrW = NULL; + /* + * TODO: Examine what can go wrong if Tcl_Flush() call disturbs + * the stacking state of this channel during its operations. + */ if (Tcl_Flush((Tcl_Channel) prevChanPtr) != TCL_OK) { statePtr->csPtrR = csPtrR; statePtr->csPtrW = csPtrW; @@ -1778,17 +1857,17 @@ Tcl_StackChannel( */ if (((mask & TCL_READABLE) != 0) && (statePtr->inQueueHead != NULL)) { + /* - * Remark: It is possible that the channel buffers contain data from - * some earlier push-backs. + * When statePtr->inQueueHead is not NULL, we know + * prevChanPtr->inQueueHead must be NULL. */ - statePtr->inQueueTail->nextPtr = prevChanPtr->inQueueHead; - prevChanPtr->inQueueHead = statePtr->inQueueHead; + assert(prevChanPtr->inQueueHead == NULL); + assert(prevChanPtr->inQueueTail == NULL); - if (prevChanPtr->inQueueTail == NULL) { - prevChanPtr->inQueueTail = statePtr->inQueueTail; - } + prevChanPtr->inQueueHead = statePtr->inQueueHead; + prevChanPtr->inQueueTail = statePtr->inQueueTail; statePtr->inQueueHead = NULL; statePtr->inQueueTail = NULL; @@ -1810,6 +1889,7 @@ Tcl_StackChannel( chanPtr->upChanPtr = NULL; chanPtr->inQueueHead = NULL; chanPtr->inQueueTail = NULL; + chanPtr->refCount = 0; /* * Place new block at the head of a possibly existing list of previously @@ -1834,6 +1914,41 @@ Tcl_StackChannel( return (Tcl_Channel) chanPtr; } + +void +TclChannelPreserve( + Tcl_Channel chan) +{ + ((Channel *)chan)->refCount++; +} + +void +TclChannelRelease( + Tcl_Channel chan) +{ + Channel *chanPtr = (Channel *) chan; + + if (chanPtr->refCount == 0) { + Tcl_Panic("Channel released more than preserved"); + } + if (--chanPtr->refCount) { + return; + } + if (chanPtr->typePtr == NULL) { + ckfree(chanPtr); + } +} + +static void +ChannelFree( + Channel *chanPtr) +{ + if (chanPtr->refCount == 0) { + ckfree(chanPtr); + return; + } + chanPtr->typePtr = NULL; +} /* *---------------------------------------------------------------------- @@ -1876,6 +1991,13 @@ Tcl_UnstackChannel( * into the old structure. */ + /* + * TODO: Figure out how to handle the situation where the chan + * operations called below by this unstacking operation cause + * another unstacking recursively. In that case the downChanPtr + * value we're holding on to will not be the right thing. + */ + Channel *downChanPtr = chanPtr->downChanPtr; /* @@ -1973,14 +2095,9 @@ Tcl_UnstackChannel( */ result = ChanClose(chanPtr, interp); - chanPtr->typePtr = NULL; + ChannelFree(chanPtr); - /* - * AK: Tcl_NotifyChannel may hold a reference to this block of memory - */ - - Tcl_EventuallyFree(chanPtr, TCL_DYNAMIC); - UpdateInterest(downChanPtr); + UpdateInterest(statePtr->topChanPtr); if (result != 0) { Tcl_SetErrno(result); @@ -2300,6 +2417,9 @@ static void PreserveChannelBuffer( ChannelBuffer *bufPtr) { + if (bufPtr->refCount == 0) { + Tcl_Panic("Reuse of ChannelBuffer! %p", bufPtr); + } bufPtr->refCount++; } @@ -2359,12 +2479,12 @@ RecycleBuffer( } /* - * Only save buffers which are at least as big as the requested buffersize - * for the channel. This is to honor dynamic changes of the buffersize + * Only save buffers which have the requested buffersize for the + * channel. This is to honor dynamic changes of the buffersize * made by the user. */ - if ((bufPtr->bufLength - BUFFER_PADDING) < statePtr->bufSize) { + if ((bufPtr->bufLength - BUFFER_PADDING) != statePtr->bufSize) { ReleaseChannelBuffer(bufPtr); return; } @@ -2438,6 +2558,11 @@ DiscardOutputQueued( } statePtr->outQueueHead = NULL; statePtr->outQueueTail = NULL; + bufPtr = statePtr->curOutPtr; + if (bufPtr && BytesLeft(bufPtr)) { + statePtr->curOutPtr = NULL; + RecycleBuffer(statePtr, bufPtr, 0); + } } /* @@ -2505,8 +2630,6 @@ FlushChannel( ChannelState *statePtr = chanPtr->state; /* State of the channel stack. */ ChannelBuffer *bufPtr; /* Iterates over buffered output queue. */ - int toWrite; /* Amount of output data in current buffer - * available to be written. */ int written; /* Amount of output data actually written in * current round. */ int errorCode = 0; /* Stores POSIX error codes from channel @@ -2526,64 +2649,61 @@ FlushChannel( } /* - * Loop over the queued buffers and attempt to flush as much as possible - * of the queued output to the channel. - */ - - Tcl_Preserve(chanPtr); - 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 (((statePtr->curOutPtr != NULL) && - IsBufferFull(statePtr->curOutPtr)) - || (GotFlag(statePtr, BUFFER_READY) && - (statePtr->outQueueHead == NULL))) { - ResetFlag(statePtr, BUFFER_READY); - statePtr->curOutPtr->nextPtr = NULL; - if (statePtr->outQueueHead == NULL) { - statePtr->outQueueHead = statePtr->curOutPtr; - } else { - statePtr->outQueueTail->nextPtr = statePtr->curOutPtr; - } - statePtr->outQueueTail = statePtr->curOutPtr; - statePtr->curOutPtr = NULL; + * Should we shift the current output buffer over to the output queue? + * First check that there are bytes in it. If so then... + * If the output queue is empty, then yes, trusting the caller called + * us only when written bytes ought to be flushed. + * If the current output buffer is full, then yes, so we can meet + * the post-condition that on a successful return to caller we've + * left space in the current output buffer for more writing (the flush + * call was to make new room). + * If the channel is blocking, then yes, so we guarantee that + * blocking flushes actually flush all pending data. + * Otherwise, no. Keep the current output buffer where it is so more + * can be written to it, possibly filling it, to promote more efficient + * buffer usage. + */ + + bufPtr = statePtr->curOutPtr; + if (bufPtr && BytesLeft(bufPtr) && /* Keep empties off queue */ + (statePtr->outQueueHead == NULL || IsBufferFull(bufPtr) + || !GotFlag(statePtr, CHANNEL_NONBLOCKING))) { + if (statePtr->outQueueHead == NULL) { + statePtr->outQueueHead = bufPtr; + } else { + statePtr->outQueueTail->nextPtr = bufPtr; } - bufPtr = statePtr->outQueueHead; + statePtr->outQueueTail = bufPtr; + statePtr->curOutPtr = NULL; + } - /* - * If we are not being called from an async flush and an async flush - * is active, we just return without producing any output. - */ + assert(!IsBufferFull(statePtr->curOutPtr)); - if (!calledFromAsyncFlush && GotFlag(statePtr, BG_FLUSH_SCHEDULED)) { - errorCode = 0; - goto done; - } + /* + * If we are not being called from an async flush and an async flush + * is active, we just return without producing any output. + */ - /* - * If the output queue is still empty, break out of the while loop. - */ + if (!calledFromAsyncFlush && GotFlag(statePtr, BG_FLUSH_SCHEDULED)) { + return 0; + } - if (bufPtr == NULL) { - break; /* Out of the "while (1)". */ - } + /* + * Loop over the queued buffers and attempt to flush as much as possible + * of the queued output to the channel. + */ + + TclChannelPreserve((Tcl_Channel)chanPtr); + while (statePtr->outQueueHead) { + bufPtr = statePtr->outQueueHead; /* * Produce the output on the channel. */ PreserveChannelBuffer(bufPtr); - toWrite = BytesLeft(bufPtr); - if (toWrite == 0) { - written = 0; - } else { - written = ChanWrite(chanPtr, RemovePoint(bufPtr), toWrite, - &errorCode); - } + written = ChanWrite(chanPtr, RemovePoint(bufPtr), BytesLeft(bufPtr), + &errorCode); /* * If the write failed completely attempt to start the asynchronous @@ -2598,6 +2718,7 @@ FlushChannel( if (errorCode == EINTR) { errorCode = 0; + ReleaseChannelBuffer(bufPtr); continue; } @@ -2619,6 +2740,7 @@ FlushChannel( UpdateInterest(chanPtr); } errorCode = 0; + ReleaseChannelBuffer(bufPtr); break; } @@ -2680,14 +2802,15 @@ FlushChannel( */ DiscardOutputQueued(statePtr); - continue; + ReleaseChannelBuffer(bufPtr); + break; } else { + /* TODO: Consider detecting and reacting to short writes + * on blocking channels. Ought not happen. See iocmd-24.2. */ wroteSome = 1; } - if (!IsBufferEmpty(bufPtr)) { - bufPtr->nextRemoved += written; - } + bufPtr->nextRemoved += written; /* * If this buffer is now empty, recycle it. @@ -2701,7 +2824,7 @@ FlushChannel( RecycleBuffer(statePtr, bufPtr, 0); } ReleaseChannelBuffer(bufPtr); - } /* Closes "while (1)". */ + } /* Closes "while". */ /* * If we wrote some data while flushing in the background, we are done. @@ -2716,6 +2839,25 @@ FlushChannel( } else if (statePtr->outQueueHead == NULL) { ResetFlag(statePtr, BG_FLUSH_SCHEDULED); ChanWatch(chanPtr, statePtr->interestMask); + } else { + + /* + * When we are calledFromAsyncFlush, that means a writable + * state on the channel triggered the call, so we should be + * able to write something. Either we did write something + * and wroteSome should be set, or there was nothing left to + * write in this call, and we've completed the BG flush. + * These are the two cases above. If we get here, that means + * there is some kind failure in the writable event machinery. + * + * The tls extension indeed suffers from flaws in its channel + * event mgmt. See http://core.tcl.tk/tcl/info/c31ca233ca. + * Until that patch is broadly distributed, disable the + * assertion checking here, so that programs using Tcl and + * tls can be debugged. + + assert(!calledFromAsyncFlush); + */ } } @@ -2748,7 +2890,7 @@ FlushChannel( } done: - Tcl_Release(chanPtr); + TclChannelRelease((Tcl_Channel)chanPtr); return errorCode; } @@ -2914,9 +3056,9 @@ CloseChannel( statePtr->topChanPtr = downChanPtr; downChanPtr->upChanPtr = NULL; - chanPtr->typePtr = NULL; - Tcl_EventuallyFree(chanPtr, TCL_DYNAMIC); + ChannelFree(chanPtr); + return Tcl_Close(interp, (Tcl_Channel) downChanPtr); } @@ -2924,13 +3066,11 @@ CloseChannel( * There is only the TOP Channel, so we free the remaining pointers we * have and then ourselves. Since this is the last of the channels in the * stack, make sure to free the ChannelState structure associated with it. - * We use Tcl_EventuallyFree to allow for any last references. */ - chanPtr->typePtr = NULL; + ChannelFree(chanPtr); Tcl_EventuallyFree(statePtr, TCL_DYNAMIC); - Tcl_EventuallyFree(chanPtr, TCL_DYNAMIC); return errorCode; } @@ -3214,11 +3354,18 @@ Tcl_Close( stickyError = 0; - if ((statePtr->encoding != NULL) - && !(statePtr->outputEncodingFlags & TCL_ENCODING_START) - && (CheckChannelErrors(statePtr, TCL_WRITABLE) == 0)) { - statePtr->outputEncodingFlags |= TCL_ENCODING_END; - if (WriteChars(chanPtr, "", 0) < 0) { + if (GotFlag(statePtr, TCL_WRITABLE) && (statePtr->encoding != NULL) + && !(statePtr->outputEncodingFlags & TCL_ENCODING_START)) { + + int code = CheckChannelErrors(statePtr, TCL_WRITABLE); + + if (code == 0) { + statePtr->outputEncodingFlags |= TCL_ENCODING_END; + code = WriteChars(chanPtr, "", 0); + statePtr->outputEncodingFlags &= ~TCL_ENCODING_END; + statePtr->outputEncodingFlags |= TCL_ENCODING_START; + } + if (code < 0) { stickyError = Tcl_GetErrno(); } @@ -3253,14 +3400,6 @@ Tcl_Close( ResetFlag(statePtr, CHANNEL_INCLOSE); /* - * Ensure that the last output buffer will be flushed. - */ - - if ((statePtr->curOutPtr != NULL) && IsBufferReady(statePtr->curOutPtr)) { - SetFlag(statePtr, BUFFER_READY); - } - - /* * If this channel supports it, close the read side, since we don't need * it anymore and this will help avoid deadlocks on some channel types. */ @@ -3428,10 +3567,6 @@ Tcl_CloseEx( return CloseChannelPart(interp, chanPtr, 0, flags); } else if (flags & TCL_CLOSE_WRITE) { - if ((statePtr->curOutPtr != NULL) && - IsBufferReady(statePtr->curOutPtr)) { - SetFlag(statePtr, BUFFER_READY); - } Tcl_Preserve(statePtr); if (!GotFlag(statePtr, BG_FLUSH_SCHEDULED)) { /* @@ -3493,14 +3628,6 @@ CloseWrite( int result = 0; /* - * Ensure that the last output buffer will be flushed. - */ - - if ((statePtr->curOutPtr != NULL) && IsBufferReady(statePtr->curOutPtr)) { - SetFlag(statePtr, 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. @@ -3812,7 +3939,10 @@ Tcl_Write( if (srcLen < 0) { srcLen = strlen(src); } - return WriteBytes(chanPtr, src, srcLen); + if (WriteBytes(chanPtr, src, srcLen) < 0) { + return -1; + } + return srcLen; } /* @@ -4014,15 +4144,23 @@ WillRead( { if (chanPtr->typePtr == NULL) { /* Prevent read attempts on a closed channel */ + DiscardInputQueued(chanPtr->state, 0); Tcl_SetErrno(EINVAL); return -1; } if ((chanPtr->typePtr->seekProc != NULL) && (Tcl_OutputBuffered((Tcl_Channel) chanPtr) > 0)) { - if ((chanPtr->state->curOutPtr != NULL) - && IsBufferReady(chanPtr->state->curOutPtr)) { - SetFlag(chanPtr->state, BUFFER_READY); - } + + /* + * CAVEAT - The assumption here is that FlushChannel() will + * push out the bytes of any writes that are in progress. + * Since this is a seekable channel, we assume it is not one + * that can block and force bg flushing. Channels we know that + * can do that -- sockets, pipes -- are not seekable. If the + * assumption is wrong, more drastic measures may be required here + * like temporarily setting the channel into blocking mode. + */ + if (FlushChannel(NULL, chanPtr, 0) != 0) { return -1; } @@ -4160,9 +4298,7 @@ Write( &statePtr->outputEncodingState, dst, dstLen + BUFFER_PADDING, &srcRead, &dstWrote, NULL); - if (srcRead != nlLen) { - Tcl_Panic("Can This Happen?"); - } + assert (srcRead == nlLen); bufPtr->nextAdded += dstWrote; src++; @@ -4194,6 +4330,7 @@ Write( if (IsBufferFull(bufPtr)) { if (FlushChannel(NULL, chanPtr, 0) != 0) { + ReleaseChannelBuffer(bufPtr); return -1; } flushed += statePtr->bufSize; @@ -4205,7 +4342,6 @@ Write( } if ((flushed < total) && (GotFlag(statePtr, CHANNEL_UNBUFFERED) || (needNlFlush && GotFlag(statePtr, CHANNEL_LINEBUFFERED)))) { - SetFlag(statePtr, BUFFER_READY); if (FlushChannel(NULL, chanPtr, 0) != 0) { return -1; } @@ -4293,8 +4429,22 @@ Tcl_GetsObj( Tcl_EncodingState oldState; if (CheckChannelErrors(statePtr, TCL_READABLE) != 0) { - copiedTotal = -1; - goto done; + return -1; + } + + /* + * If we're sitting ready to read the eofchar, there's no need to + * do it. + */ + + if (GotFlag(statePtr, CHANNEL_STICKY_EOF)) { + SetFlag(statePtr, CHANNEL_EOF); + assert( statePtr->inputEncodingFlags & TCL_ENCODING_END ); + assert( !GotFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR) ); + + /* TODO: Do we need this? */ + UpdateInterest(chanPtr); + return -1; } /* @@ -4314,7 +4464,7 @@ Tcl_GetsObj( */ chanPtr = statePtr->topChanPtr; - Tcl_Preserve(chanPtr); + TclChannelPreserve((Tcl_Channel)chanPtr); bufPtr = statePtr->inQueueHead; encoding = statePtr->encoding; @@ -4363,6 +4513,7 @@ Tcl_GetsObj( eof = NULL; inEofChar = statePtr->inEofChar; + ResetFlag(statePtr, CHANNEL_BLOCKED); while (1) { if (dst >= dstEnd) { if (FilterInputBytes(chanPtr, &gs) != 0) { @@ -4454,14 +4605,14 @@ Tcl_GetsObj( * Skip the raw bytes that make up the '\n'. */ - char tmp[1 + TCL_UTF_MAX]; + char tmp[TCL_UTF_MAX]; int rawRead; bufPtr = gs.bufPtr; Tcl_ExternalToUtf(NULL, gs.encoding, RemovePoint(bufPtr), - gs.rawRead, statePtr->inputEncodingFlags, - &gs.state, tmp, 1 + TCL_UTF_MAX, &rawRead, NULL, - NULL); + gs.rawRead, statePtr->inputEncodingFlags + | TCL_ENCODING_NO_TERMINATE, &gs.state, tmp, + TCL_UTF_MAX, &rawRead, NULL, NULL); bufPtr->nextRemoved += rawRead; gs.rawRead -= rawRead; gs.bytesWrote--; @@ -4514,6 +4665,7 @@ Tcl_GetsObj( dstEnd = eof; SetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF); statePtr->inputEncodingFlags |= TCL_ENCODING_END; + ResetFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR); } if (GotFlag(statePtr, CHANNEL_EOF)) { skip = 0; @@ -4527,6 +4679,7 @@ Tcl_GetsObj( Tcl_SetObjLength(objPtr, oldLength); CommonGetsCleanup(chanPtr); copiedTotal = -1; + ResetFlag(statePtr, CHANNEL_BLOCKED); goto done; } goto gotEOL; @@ -4547,9 +4700,12 @@ Tcl_GetsObj( * Regenerate the top channel, in case it was changed due to * self-modifying reflected transforms. */ - /* - chanPtr = statePtr->topChanPtr; - */ + + if (chanPtr != statePtr->topChanPtr) { + TclChannelRelease((Tcl_Channel)chanPtr); + chanPtr = statePtr->topChanPtr; + TclChannelPreserve((Tcl_Channel)chanPtr); + } bufPtr = gs.bufPtr; if (bufPtr == NULL) { @@ -4557,8 +4713,9 @@ Tcl_GetsObj( } statePtr->inputEncodingState = gs.state; Tcl_ExternalToUtf(NULL, gs.encoding, RemovePoint(bufPtr), gs.rawRead, - statePtr->inputEncodingFlags, &statePtr->inputEncodingState, dst, - eol - dst + skip + TCL_UTF_MAX, &gs.rawRead, NULL, + statePtr->inputEncodingFlags | TCL_ENCODING_NO_TERMINATE, + &statePtr->inputEncodingState, dst, + eol - dst + skip + TCL_UTF_MAX - 1, &gs.rawRead, NULL, &gs.charsWrote); bufPtr->nextRemoved += gs.rawRead; @@ -4583,9 +4740,11 @@ Tcl_GetsObj( * Regenerate the top channel, in case it was changed due to * self-modifying reflected transforms. */ - /* - chanPtr = statePtr->topChanPtr; - */ + if (chanPtr != statePtr->topChanPtr) { + TclChannelRelease((Tcl_Channel)chanPtr); + chanPtr = statePtr->topChanPtr; + TclChannelPreserve((Tcl_Channel)chanPtr); + } bufPtr = statePtr->inQueueHead; if (bufPtr != NULL) { bufPtr->nextRemoved = oldRemoved; @@ -4621,15 +4780,24 @@ Tcl_GetsObj( */ done: + assert(!GotFlag(statePtr, CHANNEL_EOF) + || GotFlag(statePtr, CHANNEL_STICKY_EOF) + || Tcl_InputBuffered((Tcl_Channel)chanPtr) == 0); + + assert( !(GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED) + == (CHANNEL_EOF|CHANNEL_BLOCKED)) ); + /* * Regenerate the top channel, in case it was changed due to * self-modifying reflected transforms. */ - /* - chanPtr = statePtr->topChanPtr; - */ + if (chanPtr != statePtr->topChanPtr) { + TclChannelRelease((Tcl_Channel)chanPtr); + chanPtr = statePtr->topChanPtr; + TclChannelPreserve((Tcl_Channel)chanPtr); + } UpdateInterest(chanPtr); - Tcl_Release(chanPtr); + TclChannelRelease((Tcl_Channel)chanPtr); return copiedTotal; } @@ -4642,6 +4810,11 @@ Tcl_GetsObj( * end-of-line or end-of-file has been seen. Bytes read from the input * channel return as a ByteArray obj. * + * WARNING! The notion of "binary" used here is different from + * notions of "binary" used in other places. In particular, this + * "binary" routine may be called when an -eofchar is set on the + * channel. + * * Results: * Number of characters accumulated in the object or -1 if error, * blocked, or EOF. If -1, use Tcl_GetErrno() to retrieve the POSIX error @@ -4675,7 +4848,7 @@ TclGetsObjBinary( */ chanPtr = statePtr->topChanPtr; - Tcl_Preserve(chanPtr); + TclChannelPreserve((Tcl_Channel)chanPtr); bufPtr = statePtr->inQueueHead; @@ -4703,6 +4876,7 @@ TclGetsObjBinary( eolChar = (statePtr->inputTranslation == TCL_TRANSLATE_LF) ? '\n' : '\r'; + ResetFlag(statePtr, CHANNEL_BLOCKED); while (1) { /* * Subtract the number of bytes that were removed from channel @@ -4722,13 +4896,6 @@ TclGetsObjBinary( * hasn't seen EOL. Need to read more bytes from the channel * device. Side effect is to allocate another channel buffer. */ - - if (GotFlag(statePtr, CHANNEL_BLOCKED)) { - if (GotFlag(statePtr, CHANNEL_NONBLOCKING)) { - goto restore; - } - ResetFlag(statePtr, CHANNEL_BLOCKED); - } if (GetInput(chanPtr) != 0) { goto restore; } @@ -4736,6 +4903,17 @@ TclGetsObjBinary( if (bufPtr == NULL) { goto restore; } + } else { + /* + * Incoming CHANNEL_STICKY_EOF is filtered out on entry. + * A new CHANNEL_STICKY_EOF set in this routine leads to + * return before coming back here. When we are not dealing + * with CHANNEL_STICKY_EOF, a CHANNEL_EOF implies an + * empty buffer. Here the buffer is non-empty so we know + * we're a non-EOF */ + + assert ( !GotFlag(statePtr, CHANNEL_STICKY_EOF) ); + assert ( !GotFlag(statePtr, CHANNEL_EOF) ); } dst = (unsigned char *) RemovePoint(bufPtr); @@ -4777,6 +4955,7 @@ TclGetsObjBinary( SetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF); statePtr->inputEncodingFlags |= TCL_ENCODING_END; + ResetFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR); } if (GotFlag(statePtr, CHANNEL_EOF)) { skip = 0; @@ -4790,10 +4969,15 @@ TclGetsObjBinary( byteArray = Tcl_SetByteArrayLength(objPtr, oldLength); CommonGetsCleanup(chanPtr); copiedTotal = -1; + ResetFlag(statePtr, CHANNEL_BLOCKED); goto done; } goto gotEOL; } + if (GotFlag(statePtr, CHANNEL_BLOCKED|CHANNEL_NONBLOCKING) + == (CHANNEL_BLOCKED|CHANNEL_NONBLOCKING)) { + goto restore; + } /* * Copy bytes from the channel buffer to the ByteArray. @@ -4881,8 +5065,13 @@ TclGetsObjBinary( */ done: + assert(!GotFlag(statePtr, CHANNEL_EOF) + || GotFlag(statePtr, CHANNEL_STICKY_EOF) + || Tcl_InputBuffered((Tcl_Channel)chanPtr) == 0); + assert( !(GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED) + == (CHANNEL_EOF|CHANNEL_BLOCKED)) ); UpdateInterest(chanPtr); - Tcl_Release(chanPtr); + TclChannelRelease((Tcl_Channel)chanPtr); return copiedTotal; } @@ -4959,7 +5148,7 @@ FilterInputBytes( ChannelState *statePtr = chanPtr->state; /* State info for channel */ ChannelBuffer *bufPtr; - char *raw, *rawStart, *dst; + char *raw, *dst; int offset, toRead, dstNeeded, spaceLeft, result, rawLen; Tcl_Obj *objPtr; #define ENCODING_LINESIZE 20 /* Lower bound on how many bytes to convert at @@ -4993,13 +5182,11 @@ FilterInputBytes( */ read: - if (GotFlag(statePtr, CHANNEL_BLOCKED)) { - if (GotFlag(statePtr, CHANNEL_NONBLOCKING)) { - gsPtr->charsWrote = 0; - gsPtr->rawRead = 0; - return -1; - } - ResetFlag(statePtr, CHANNEL_BLOCKED); + if (GotFlag(statePtr, CHANNEL_NONBLOCKING|CHANNEL_BLOCKED) + == (CHANNEL_NONBLOCKING|CHANNEL_BLOCKED)) { + gsPtr->charsWrote = 0; + gsPtr->rawRead = 0; + return -1; } if (GetInput(chanPtr) != 0) { gsPtr->charsWrote = 0; @@ -5013,6 +5200,17 @@ FilterInputBytes( gsPtr->rawRead = 0; return -1; } + } else { + /* + * Incoming CHANNEL_STICKY_EOF is filtered out on entry. + * A new CHANNEL_STICKY_EOF set in this routine leads to + * return before coming back here. When we are not dealing + * with CHANNEL_STICKY_EOF, a CHANNEL_EOF implies an + * empty buffer. Here the buffer is non-empty so we know + * we're a non-EOF */ + + assert ( !GotFlag(statePtr, CHANNEL_STICKY_EOF) ); + assert ( !GotFlag(statePtr, CHANNEL_EOF) ); } /* @@ -5021,8 +5219,7 @@ FilterInputBytes( * string rep if we need more space. */ - rawStart = RemovePoint(bufPtr); - raw = rawStart; + raw = RemovePoint(bufPtr); rawLen = BytesLeft(bufPtr); dst = *gsPtr->dstPtr; @@ -5050,9 +5247,9 @@ FilterInputBytes( } gsPtr->state = statePtr->inputEncodingState; result = Tcl_ExternalToUtf(NULL, gsPtr->encoding, raw, rawLen, - statePtr->inputEncodingFlags, &statePtr->inputEncodingState, - dst, spaceLeft+1, &gsPtr->rawRead, &gsPtr->bytesWrote, - &gsPtr->charsWrote); + statePtr->inputEncodingFlags | TCL_ENCODING_NO_TERMINATE, + &statePtr->inputEncodingState, dst, spaceLeft, &gsPtr->rawRead, + &gsPtr->bytesWrote, &gsPtr->charsWrote); /* * Make sure that if we go through 'gets', that we reset the @@ -5089,7 +5286,7 @@ FilterInputBytes( } else { /* * There are no more cached raw bytes left. See if we can get - * some more. + * some more, but avoid blocking on a non-blocking channel. */ goto read; @@ -5330,138 +5527,87 @@ Tcl_Read( int Tcl_ReadRaw( Tcl_Channel chan, /* The channel from which to read. */ - char *bufPtr, /* Where to store input read. */ + char *readBuf, /* Where to store input read. */ int bytesToRead) /* Maximum number of bytes to read. */ { Channel *chanPtr = (Channel *) chan; ChannelState *statePtr = chanPtr->state; /* State info for channel */ - int nread, result, copied, copiedNow; - - /* - * The check below does too much because it will reject a call to this - * function with a channel which is part of an 'fcopy'. But we have to - * allow this here or else the chaining in the transformation drivers will - * fail with 'file busy' error instead of retrieving and transforming the - * data to copy. - * - * We let the check procedure now believe that there is no fcopy in - * progress. A better solution than this might be an additional flag - * argument to switch off specific checks. - */ + int copied = 0; + assert(bytesToRead > 0); if (CheckChannelErrors(statePtr, TCL_READABLE | CHANNEL_RAW_MODE) != 0) { return -1; } - /* - * Check for information in the push-back buffers. If there is some, use - * it. Go to the driver only if there is none (anymore) and the caller - * requests more bytes. - */ + /* First read bytes from the push-back buffers. */ - Tcl_Preserve(chanPtr); - for (copied = 0; copied < bytesToRead; copied += copiedNow) { - copiedNow = CopyBuffer(chanPtr, bufPtr + copied, - bytesToRead - copied); - if (copiedNow == 0) { - if (GotFlag(statePtr, CHANNEL_EOF)) { - goto done; - } - if (GotFlag(statePtr, CHANNEL_BLOCKED)) { - if (GotFlag(statePtr, CHANNEL_NONBLOCKING)) { - goto done; - } - ResetFlag(statePtr, CHANNEL_BLOCKED); - } + while (chanPtr->inQueueHead && bytesToRead > 0) { + ChannelBuffer *bufPtr = chanPtr->inQueueHead; + int bytesInBuffer = BytesLeft(bufPtr); + int toCopy = (bytesInBuffer < bytesToRead) ? bytesInBuffer + : bytesToRead; -#ifdef TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING - /* - * [Bug 943274]. Better emulation of non-blocking channels for - * channels without BlockModeProc, by keeping track of true - * fileevents generated by the OS == Data waiting and reading if - * and only if we are sure to have data. - */ + /* Copy the current chunk into the read buffer. */ - if (GotFlag(statePtr, CHANNEL_NONBLOCKING) && - (Tcl_ChannelBlockModeProc(chanPtr->typePtr) == NULL) && - !GotFlag(statePtr, CHANNEL_HAS_MORE_DATA)) { - /* - * We bypass the driver; it would block as no data is - * available. - */ + memcpy(readBuf, RemovePoint(bufPtr), (size_t) toCopy); + bufPtr->nextRemoved += toCopy; + copied += toCopy; + readBuf += toCopy; + bytesToRead -= toCopy; - nread = -1; - result = EWOULDBLOCK; - } else -#endif /* TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING */ - { - /* - * Now go to the driver to get as much as is possible to fill - * the remaining request. Do all the error handling by - * ourselves. The code was stolen from 'GetInput' and slightly - * adapted (different return value here). - * - * The case of 'bytesToRead == 0' at this point cannot happen. - */ + /* If the current buffer is empty recycle it. */ - nread = ChanRead(chanPtr, bufPtr + copied, - bytesToRead - copied, &result); + if (IsBufferEmpty(bufPtr)) { + chanPtr->inQueueHead = bufPtr->nextPtr; + if (chanPtr->inQueueHead == NULL) { + chanPtr->inQueueTail = NULL; } + RecycleBuffer(chanPtr->state, bufPtr, 0); + } + } - if (nread > 0) { - /* - * 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 < (bytesToRead - copied)) { - SetFlag(statePtr, CHANNEL_BLOCKED); - } - -#ifdef TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING - if (nread <= (bytesToRead - copied)) { - /* - * [Bug 943274] We have read the available data, clear - * flag. - */ + /* + * Go to the driver only if we got nothing from pushback. + * Have to do it this way to avoid EOF mis-timings when we + * consider the ability that EOF may not be a permanent + * condition in the driver, and in that case we have to + * synchronize. + */ - ResetFlag(statePtr, CHANNEL_HAS_MORE_DATA); - } -#endif /* TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING */ - } else if (nread == 0) { - SetFlag(statePtr, CHANNEL_EOF); - statePtr->inputEncodingFlags |= TCL_ENCODING_END; - - } else if (nread < 0) { - if ((result == EWOULDBLOCK) || (result == EAGAIN)) { - if (copied > 0) { - /* - * Information that was copied earlier has precedence - * over EAGAIN/WOULDBLOCK handling. - */ + if (copied) { + return copied; + } - goto done; - } + /* This test not needed. */ + if (bytesToRead > 0) { - SetFlag(statePtr, CHANNEL_BLOCKED); - result = EAGAIN; - } + int nread = ChanRead(chanPtr, readBuf, bytesToRead); - Tcl_SetErrno(result); + if (nread > 0) { + /* Successful read (short is OK) - add to bytes copied */ + copied += nread; + } else if (nread < 0) { + /* + * An error signaled. If CHANNEL_BLOCKED, then the error + * is not real, but an indication of blocked state. In + * that case, retain the flag and let caller receive the + * short read of copied bytes from the pushback. + * HOWEVER, if copied==0 bytes from pushback then repeat + * signalling the blocked state as an error to caller so + * there is no false report of an EOF. + * When !CHANNEL_BLOCKED, the error is real and passes on + * to caller. + */ + if (!GotFlag(statePtr, CHANNEL_BLOCKED) || copied == 0) { copied = -1; - goto done; } - - copied += nread; - goto done; + } else { + /* + * nread == 0. Driver is at EOF. Let that state filter up. + */ } } - - done: - Tcl_Release(chanPtr); return copied; } @@ -5558,21 +5704,18 @@ DoReadChars( ChannelState *statePtr = chanPtr->state; /* State info for channel */ ChannelBuffer *bufPtr; - int offset, factor, copied, copiedNow, result; - Tcl_Encoding encoding; + int copied, copiedNow, result; + Tcl_Encoding encoding = statePtr->encoding; + int binaryMode; #define UTF_EXPANSION_FACTOR 1024 + int factor = UTF_EXPANSION_FACTOR; - /* - * This operation should occur at the top of a channel stack. - */ - - chanPtr = statePtr->topChanPtr; - encoding = statePtr->encoding; - factor = UTF_EXPANSION_FACTOR; - Tcl_Preserve(chanPtr); + binaryMode = (encoding == NULL) + && (statePtr->inputTranslation == TCL_TRANSLATE_LF) + && (statePtr->inEofChar == '\0'); if (appendFlag == 0) { - if (encoding == NULL) { + if (binaryMode) { Tcl_SetByteArrayLength(objPtr, 0); } else { Tcl_SetObjLength(objPtr, 0); @@ -5581,27 +5724,61 @@ DoReadChars( * We're going to access objPtr->bytes directly, so we must ensure * that this is actually a string object (otherwise it might have * been pure Unicode). + * + * Probably not needed anymore. */ TclGetString(objPtr); } - offset = 0; - } else { - if (encoding == NULL) { - Tcl_GetByteArrayFromObj(objPtr, &offset); - } else { - TclGetStringFromObj(objPtr, &offset); + } + + /* + * Early out when next read will see eofchar. + * + * NOTE: See DoRead for argument that it's a bug (one we're keeping) + * to have this escape before the one for zero-char read request. + */ + + if (GotFlag(statePtr, CHANNEL_STICKY_EOF)) { + SetFlag(statePtr, CHANNEL_EOF); + assert( statePtr->inputEncodingFlags & TCL_ENCODING_END ); + assert( !GotFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR) ); + + UpdateInterest(chanPtr); + return 0; + } + + /* Special handling for zero-char read request. */ + if (toRead == 0) { + if (GotFlag(statePtr, CHANNEL_EOF)) { + statePtr->inputEncodingFlags |= TCL_ENCODING_START; } + ResetFlag(statePtr, CHANNEL_BLOCKED|CHANNEL_EOF); + statePtr->inputEncodingFlags &= ~TCL_ENCODING_END; + UpdateInterest(chanPtr); + return 0; } + /* + * This operation should occur at the top of a channel stack. + */ + + chanPtr = statePtr->topChanPtr; + TclChannelPreserve((Tcl_Channel)chanPtr); + + /* Must clear the BLOCKED|EOF flags here since we check before reading */ + if (GotFlag(statePtr, CHANNEL_EOF)) { + statePtr->inputEncodingFlags |= TCL_ENCODING_START; + } + ResetFlag(statePtr, CHANNEL_BLOCKED|CHANNEL_EOF); + statePtr->inputEncodingFlags &= ~TCL_ENCODING_END; for (copied = 0; (unsigned) toRead > 0; ) { copiedNow = -1; if (statePtr->inQueueHead != NULL) { - if (encoding == NULL) { - copiedNow = ReadBytes(statePtr, objPtr, toRead, &offset); + if (binaryMode) { + copiedNow = ReadBytes(statePtr, objPtr, toRead); } else { - copiedNow = ReadChars(statePtr, objPtr, toRead, &offset, - &factor); + copiedNow = ReadChars(statePtr, objPtr, toRead, &factor); } /* @@ -5624,19 +5801,21 @@ DoReadChars( if (GotFlag(statePtr, CHANNEL_EOF)) { break; } - if (GotFlag(statePtr, CHANNEL_BLOCKED)) { - if (GotFlag(statePtr, CHANNEL_NONBLOCKING)) { - break; - } - ResetFlag(statePtr, CHANNEL_BLOCKED); + if (GotFlag(statePtr, CHANNEL_NONBLOCKING|CHANNEL_BLOCKED) + == (CHANNEL_NONBLOCKING|CHANNEL_BLOCKED)) { + break; } result = GetInput(chanPtr); + if (chanPtr != statePtr->topChanPtr) { + TclChannelRelease((Tcl_Channel)chanPtr); + chanPtr = statePtr->topChanPtr; + TclChannelPreserve((Tcl_Channel)chanPtr); + } if (result != 0) { - if (result == EAGAIN) { - break; + if (!GotFlag(statePtr, CHANNEL_BLOCKED)) { + copied = -1; } - copied = -1; - goto done; + break; } } else { copied += copiedNow; @@ -5644,28 +5823,36 @@ DoReadChars( } } - ResetFlag(statePtr, CHANNEL_BLOCKED); - if (encoding == NULL) { - Tcl_SetByteArrayLength(objPtr, offset); - } else { - Tcl_SetObjLength(objPtr, offset); - } - /* - * Update the notifier state so we don't block while there is still data - * in the buffers. + * Failure to fill a channel buffer may have left channel reporting + * a "blocked" state, but so long as we fulfilled the request here, + * the caller does not consider us blocked. */ + if (toRead == 0) { + ResetFlag(statePtr, CHANNEL_BLOCKED); + } - done: /* * Regenerate the top channel, in case it was changed due to * self-modifying reflected transforms. */ + if (chanPtr != statePtr->topChanPtr) { + TclChannelRelease((Tcl_Channel)chanPtr); + chanPtr = statePtr->topChanPtr; + TclChannelPreserve((Tcl_Channel)chanPtr); + } + /* - chanPtr = statePtr->topChanPtr; + * Update the notifier state so we don't block while there is still data + * in the buffers. */ + assert(!GotFlag(statePtr, CHANNEL_EOF) + || GotFlag(statePtr, CHANNEL_STICKY_EOF) + || Tcl_InputBuffered((Tcl_Channel)chanPtr) == 0); + assert( !(GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED) + == (CHANNEL_EOF|CHANNEL_BLOCKED)) ); UpdateInterest(chanPtr); - Tcl_Release(chanPtr); + TclChannelRelease((Tcl_Channel)chanPtr); return copied; } @@ -5683,13 +5870,11 @@ DoReadChars( * allocated to hold data read from the channel as needed. * * Results: - * The return value is the number of bytes appended to the object and - * *offsetPtr is filled with the total number of bytes in the object - * (greater than the return value if there were already bytes in the - * object). + * The return value is the number of bytes appended to the object, or + * -1 to indicate that zero bytes were read due to an EOF. * * Side effects: - * None. + * The storage of bytes in objPtr can cause (re-)allocation of memory. * *--------------------------------------------------------------------------- */ @@ -5702,72 +5887,22 @@ ReadBytes( * been allocated to hold data, not how many * bytes of data have been stored in the * object. */ - int bytesToRead, /* Maximum number of bytes to store, or < 0 to + int bytesToRead) /* Maximum number of bytes to store, or < 0 to * get all available bytes. Bytes are obtained * from the first buffer in the queue - even * if this number is larger than the number of * bytes available in the first buffer, only * the bytes from the first buffer are * returned. */ - int *offsetPtr) /* On input, contains how many bytes of objPtr - * have been used to hold data. On output, - * filled with how many bytes are now being - * used. */ { - int toRead, srcLen, offset, length, srcRead, dstWrote; - ChannelBuffer *bufPtr; - char *src, *dst; - - offset = *offsetPtr; - - bufPtr = statePtr->inQueueHead; - src = RemovePoint(bufPtr); - srcLen = BytesLeft(bufPtr); - - toRead = bytesToRead; - if ((unsigned) toRead > (unsigned) srcLen) { - toRead = srcLen; - } - - dst = (char *) Tcl_GetByteArrayFromObj(objPtr, &length); - if (toRead > length - offset - 1) { - /* - * Double the existing size of the object or make enough room to hold - * all the characters we may get from the source buffer, whichever is - * larger. - */ - - length = offset * 2; - if (offset < toRead) { - length = offset + toRead + 1; - } - dst = (char *) Tcl_SetByteArrayLength(objPtr, length); - } - dst += offset; - - if (GotFlag(statePtr, INPUT_NEED_NL)) { - ResetFlag(statePtr, INPUT_NEED_NL); - if ((srcLen == 0) || (*src != '\n')) { - *dst = '\r'; - *offsetPtr += 1; - return 1; - } - *dst++ = '\n'; - src++; - srcLen--; - toRead--; - } + ChannelBuffer *bufPtr = statePtr->inQueueHead; + int srcLen = BytesLeft(bufPtr); + int toRead = bytesToRead>srcLen || bytesToRead<0 ? srcLen : bytesToRead; - srcRead = srcLen; - dstWrote = toRead; - if (TranslateInputEOL(statePtr, dst, src, &dstWrote, &srcRead) != 0) { - if (dstWrote == 0) { - return -1; - } - } - bufPtr->nextRemoved += srcRead; - *offsetPtr += dstWrote; - return dstWrote; + TclAppendBytesToByteArray(objPtr, (unsigned char *) RemovePoint(bufPtr), + toRead); + bufPtr->nextRemoved += toRead; + return toRead; } /* @@ -5811,262 +5946,371 @@ ReadChars( * is larger than the number of characters * available in the first buffer, only the * characters from the first buffer are - * returned. */ - int *offsetPtr, /* On input, contains how many bytes of objPtr - * have been used to hold data. On output, - * filled with how many bytes are now being - * used. */ + * returned. The execption is when there is + * not any complete character in the first + * buffer. In that case, a recursive call + * effectively obtains chars from the + * second buffer. */ int *factorPtr) /* On input, contains a guess of how many * bytes need to be allocated to hold the * result of converting N source bytes to * UTF-8. On output, contains another guess * based on the data seen so far. */ { - int toRead, factor, offset, spaceLeft, srcLen, dstNeeded; - int srcRead, dstWrote, numChars, dstRead; - ChannelBuffer *bufPtr; - char *src, *dst; - Tcl_EncodingState oldState; - int encEndFlagSuppressed = 0; + Tcl_Encoding encoding = statePtr->encoding? statePtr->encoding + : GetBinaryEncoding(); + Tcl_EncodingState savedState = statePtr->inputEncodingState; + ChannelBuffer *bufPtr = statePtr->inQueueHead; + int savedIEFlags = statePtr->inputEncodingFlags; + int savedFlags = statePtr->flags; + char *dst, *src = RemovePoint(bufPtr); + int numBytes, srcLen = BytesLeft(bufPtr); - factor = *factorPtr; - offset = *offsetPtr; - - bufPtr = statePtr->inQueueHead; - src = RemovePoint(bufPtr); - srcLen = BytesLeft(bufPtr); + /* + * One src byte can yield at most one character. So when the + * number of src bytes we plan to read is less than the limit on + * character count to be read, clearly we will remain within that + * limit, and we can use the value of "srcLen" as a tighter limit + * for sizing receiving buffers. + */ - toRead = charsToRead; - if ((unsigned) toRead > (unsigned) srcLen) { - toRead = srcLen; - } + int toRead = ((charsToRead<0)||(charsToRead > srcLen)) ? srcLen : charsToRead; /* * 'factor' is how much we guess that the bytes in the source buffer will * expand when converted to UTF-8 chars. This guess comes from analyzing * how many characters were produced by the previous pass. */ + + int factor = *factorPtr; + int dstLimit = TCL_UTF_MAX - 1 + toRead * factor / UTF_EXPANSION_FACTOR; - dstNeeded = TCL_UTF_MAX - 1 + toRead * factor / UTF_EXPANSION_FACTOR; - spaceLeft = objPtr->length - offset; - - if (dstNeeded > spaceLeft) { - /* - * Double the existing size of the object or make enough room to hold - * all the characters we want from the source buffer, whichever is - * larger. - */ - - int length = offset + ((offset < dstNeeded) ? dstNeeded : offset); - - if (Tcl_AttemptSetObjLength(objPtr, length) == 0) { - length = offset + dstNeeded; - if (Tcl_AttemptSetObjLength(objPtr, length) == 0) { - dstNeeded = TCL_UTF_MAX - 1 + toRead; - length = offset + dstNeeded; - Tcl_SetObjLength(objPtr, length); - } - } - spaceLeft = length - offset; - } + (void) TclGetStringFromObj(objPtr, &numBytes); + Tcl_AppendToObj(objPtr, NULL, dstLimit); if (toRead == srcLen) { - /* - * Want to convert the whole buffer in one pass. If we have enough - * space, convert it using all available space in object rather than - * using the factor. - */ - - dstNeeded = spaceLeft; + unsigned int size; + dst = TclGetStringStorage(objPtr, &size) + numBytes; + dstLimit = size - numBytes; + } else { + dst = TclGetString(objPtr) + numBytes; } - dst = objPtr->bytes + offset; /* - * [Bug 1462248]: The cause of the crash reported in this bug is this: - * - * - ReadChars, called with a single buffer, with a incomplete - * multi-byte character at the end (only the first byte of it). - * - Encoding translation fails, asks for more data - * - Data is read, and eof is reached, TCL_ENCODING_END (TEE) is set. - * - ReadChar is called again, converts the first buffer, but due to TEE - * it does not check for incomplete multi-byte data, and the character - * just after the end of the first buffer is a valid completion of the - * multi-byte header in the actual buffer. The conversion reads more - * characters from the buffer then present. This causes nextRemoved to - * overshoot nextAdded and the next reads compute a negative srcLen, - * cause further translations to fail, causing copying of data into the - * next buffer using bad arguments, causing the mecpy for to eventually - * fail. - * - * In the end it is a memory access bug spiraling out of control if the - * conditions are _just so_. And ultimate cause is that TEE is given to a - * conversion where it should not. TEE signals that this is the last - * buffer. Except in our case it is not. - * - * My solution is to suppress TEE if the first buffer is not the last. We - * will eventually need it given that EOF has been reached, but not right - * now. This is what the new flag "endEncSuppressFlag" is for. + * This routine is burdened with satisfying several constraints. + * It cannot append more than 'charsToRead` chars onto objPtr. + * This is measured after encoding and translation transformations + * are completed. There is no precise number of src bytes that can + * be associated with the limit. Yet, when we are done, we must know + * precisely the number of src bytes that were consumed to produce + * the appended chars, so that all subsequent bytes are left in + * the buffers for future read operations. * - * The bug in 'Tcl_Utf2UtfProc' where it read from memory behind the - * actual buffer has been fixed as well, and fixes the problem with the - * crash too, but this would still allow the generic layer to - * accidentially break a multi-byte sequence if the conditions are just - * right, because again the ExternalToUtf would be successful where it - * should not. + * The consequence is that we have no choice but to implement a + * "trial and error" approach, where in general we may need to + * perform transformations and copies multiple times to achieve + * a consistent set of results. This takes the shape of a loop. */ - if ((statePtr->inputEncodingFlags & TCL_ENCODING_END) && - (bufPtr->nextPtr != NULL)) { + while (1) { + int dstDecoded, dstRead, dstWrote, srcRead, numChars, code; + int flags = statePtr->inputEncodingFlags | TCL_ENCODING_NO_TERMINATE; + + if (charsToRead > 0) { + flags |= TCL_ENCODING_CHAR_LIMIT; + numChars = charsToRead; + } + /* - * TEE is set for a buffer which is not the last. Squash it for now, - * and restore it later, before yielding control to our caller. + * Perform the encoding transformation. Read no more than + * srcLen bytes, write no more than dstLimit bytes. + * + * Some trickiness with encoding flags here. We do not want + * the end of a buffer to be treated as the end of all input + * when the presence of bytes in a next buffer are already + * known to exist. This is checked with an assert() because + * so far no test case causing the assertion to be false has + * been created. The normal operations of channel reading + * appear to cause EOF and TCL_ENCODING_END setting to appear + * only in situations where there are no further bytes in + * any buffers. */ - statePtr->inputEncodingFlags &= ~TCL_ENCODING_END; - encEndFlagSuppressed = 1; - } + assert(bufPtr->nextPtr == NULL || BytesLeft(bufPtr->nextPtr) == 0 + || (statePtr->inputEncodingFlags & TCL_ENCODING_END) == 0); + + code = Tcl_ExternalToUtf(NULL, encoding, src, srcLen, + flags, &statePtr->inputEncodingState, + dst, dstLimit, &srcRead, &dstDecoded, &numChars); - oldState = statePtr->inputEncodingState; - if (GotFlag(statePtr, INPUT_NEED_NL)) { /* - * We want a '\n' because the last character we saw was '\r'. + * Perform the translation transformation in place. Read no more + * than the dstDecoded bytes the encoding transformation actually + * produced. Capture the number of bytes written in dstWrote. + * Capture the number of bytes actually consumed in dstRead. */ - ResetFlag(statePtr, INPUT_NEED_NL); - Tcl_ExternalToUtf(NULL, statePtr->encoding, src, srcLen, - statePtr->inputEncodingFlags, &statePtr->inputEncodingState, - dst, TCL_UTF_MAX + 1, &srcRead, &dstWrote, &numChars); - if ((dstWrote > 0) && (*dst == '\n')) { + dstWrote = dstLimit; + dstRead = dstDecoded; + TranslateInputEOL(statePtr, dst, dst, &dstWrote, &dstRead); + + if (dstRead < dstDecoded) { + /* - * The next char was a '\n'. Consume it and produce a '\n'. + * The encoding transformation produced bytes that the + * translation transformation did not consume. Why did + * this happen? */ - bufPtr->nextRemoved += srcRead; - } else { + if (statePtr->inEofChar && dst[dstRead] == statePtr->inEofChar) { + /* + * 1) There's an eof char set on the channel, and + * we saw it and stopped translating at that point. + * + * NOTE the bizarre spec of TranslateInputEOL in this case. + * Clearly the eof char had to be read in order to account + * for the stopping, but the value of dstRead does not + * include it. + * + * Also rather bizarre, our caller can only notice an + * EOF condition if we return the value -1 as the number + * of chars read. This forces us to perform a 2-call + * dance where the first call can read all the chars + * up to the eof char, and the second call is solely + * for consuming the encoded eof char then pointed at + * by src so that we can return that magic -1 value. + * This seems really wasteful, especially since + * the first decoding pass of each call is likely to + * decode many bytes beyond that eof char that's all we + * care about. + */ + + if (dstRead == 0) { + /* + * Curious choice in the eof char handling. We leave + * the eof char in the buffer. So, no need to compute + * a proper srcRead value. At this point, there + * are no chars before the eof char in the buffer. + */ + Tcl_SetObjLength(objPtr, numBytes); + return -1; + } + + { + /* + * There are chars leading the buffer before the eof + * char. Adjust the dstLimit so we go back and read + * only those and do not encounter the eof char this + * time. + */ + + dstLimit = dstRead - 1 + TCL_UTF_MAX; + statePtr->flags = savedFlags; + statePtr->inputEncodingFlags = savedIEFlags; + statePtr->inputEncodingState = savedState; + continue; + } + } + /* - * The next char was not a '\n'. Produce a '\r'. + * 2) The other way to read fewer bytes than are decoded + * is when the final byte is \r and we're in a CRLF + * translation mode so we cannot decide whether to + * record \r or \n yet. */ - *dst = '\r'; - } - statePtr->inputEncodingFlags &= ~TCL_ENCODING_START; - *offsetPtr += 1; + assert(dst[dstRead] == '\r'); + assert(statePtr->inputTranslation == TCL_TRANSLATE_CRLF); - if (encEndFlagSuppressed) { - statePtr->inputEncodingFlags |= TCL_ENCODING_END; - } - return 1; - } + if (dstWrote > 0) { + /* + * There are chars we can read before we hit the bare cr. + * Go back with a smaller dstLimit so we get them in the + * next pass, compute a matching srcRead, and don't end + * up back here in this call. + */ - Tcl_ExternalToUtf(NULL, statePtr->encoding, src, srcLen, - statePtr->inputEncodingFlags, &statePtr->inputEncodingState, dst, - dstNeeded + 1, &srcRead, &dstWrote, &numChars); + dstLimit = dstRead - 1 + TCL_UTF_MAX; + statePtr->flags = savedFlags; + statePtr->inputEncodingFlags = savedIEFlags; + statePtr->inputEncodingState = savedState; + continue; + } - if (encEndFlagSuppressed) { - statePtr->inputEncodingFlags |= TCL_ENCODING_END; - } + assert(dstWrote == 0); + assert(dstRead == 0); - if (srcRead == 0) { - /* - * Not enough bytes in src buffer to make a complete char. Copy the - * bytes to the next buffer to make a new contiguous string, then tell - * the caller to fill the buffer with more bytes. - */ + /* + * We decoded only the bare cr, and we cannot read a + * translated char from that alone. We have to know what's + * next. So why do we only have the one decoded char? + */ - ChannelBuffer *nextPtr; + if (code != TCL_OK) { + char buffer[TCL_UTF_MAX + 1]; + int read, decoded, count; + + /* + * Didn't get everything the buffer could offer + */ + + statePtr->flags = savedFlags; + statePtr->inputEncodingFlags = savedIEFlags; + statePtr->inputEncodingState = savedState; + + assert(bufPtr->nextPtr == NULL + || BytesLeft(bufPtr->nextPtr) == 0 || 0 == + (statePtr->inputEncodingFlags & TCL_ENCODING_END)); + + Tcl_ExternalToUtf(NULL, encoding, src, srcLen, + (statePtr->inputEncodingFlags | TCL_ENCODING_NO_TERMINATE), + &statePtr->inputEncodingState, buffer, TCL_UTF_MAX + 1, + &read, &decoded, &count); + + if (count == 2) { + if (buffer[1] == '\n') { + /* \r\n translate to \n */ + dst[0] = '\n'; + bufPtr->nextRemoved += read; + } else { + dst[0] = '\r'; + bufPtr->nextRemoved += srcRead; + } + + statePtr->inputEncodingFlags &= ~TCL_ENCODING_START; + + Tcl_SetObjLength(objPtr, numBytes + 1); + return 1; + } + + } else if (statePtr->flags & CHANNEL_EOF) { - nextPtr = bufPtr->nextPtr; - if (nextPtr == NULL) { - if (srcLen > 0) { /* - * There isn't enough data in the buffers to complete the next - * character, so we need to wait for more data before the next - * file event can be delivered. [Bug 478856] - * - * The exception to this is if the input buffer was completely - * empty before we tried to convert its contents. Nothing in, - * nothing out, and no incomplete character data. The - * conversion before the current one was complete. + * The bare \r is the only char and we will never read + * a subsequent char to make the determination. */ - SetFlag(statePtr, CHANNEL_NEED_MORE_DATA); + dst[0] = '\r'; + bufPtr->nextRemoved = bufPtr->nextAdded; + Tcl_SetObjLength(objPtr, numBytes + 1); + return 1; } - return -1; + + /* + * Revise the dstRead value so that the numChars calc + * below correctly computes zero characters read. + */ + + dstRead = numChars; + + /* FALL THROUGH - get more data (dstWrote == 0) */ } - /* - * Space is made at the beginning of the buffer to copy the previous - * unused bytes there. Check first if the buffer we are using actually - * has enough space at its beginning for the data we are copying. - * Because if not we will write over the buffer management - * information, especially the 'nextPtr'. - * - * Note that the BUFFER_PADDING (See AllocChannelBuffer) is used to - * prevent exactly this situation. I.e. it should never happen. - * Therefore it is ok to panic should it happen despite the - * precautions. + /* + * The translation transformation can only reduce the number + * of chars when it converts \r\n into \n. The reduction in + * the number of chars is the difference in bytes read and written. */ - if (nextPtr->nextRemoved - srcLen < 0) { - Tcl_Panic("Buffer Underflow, BUFFER_PADDING not enough"); - } + numChars -= (dstRead - dstWrote); - nextPtr->nextRemoved -= srcLen; - memcpy(RemovePoint(nextPtr), src, (size_t) srcLen); - RecycleBuffer(statePtr, bufPtr, 0); - statePtr->inQueueHead = nextPtr; - return ReadChars(statePtr, objPtr, charsToRead, offsetPtr, factorPtr); - } + if (charsToRead > 0 && numChars > charsToRead) { - dstRead = dstWrote; - if (TranslateInputEOL(statePtr, dst, dst, &dstWrote, &dstRead) != 0) { - /* - * Hit EOF char. How many bytes of src correspond to where the EOF was - * located in dst? Run the conversion again with an output buffer just - * big enough to hold the data so we can get the correct value for - * srcRead. - */ + /* + * TODO: This cannot happen anymore. + * + * We read more chars than allowed. Reset limits to + * prevent that and try again. Don't forget the extra + * padding of TCL_UTF_MAX bytes demanded by the + * Tcl_ExternalToUtf() call! + */ - if (dstWrote == 0) { - return -1; + dstLimit = Tcl_UtfAtIndex(dst, charsToRead) - 1 + TCL_UTF_MAX - dst; + statePtr->flags = savedFlags; + statePtr->inputEncodingFlags = savedIEFlags; + statePtr->inputEncodingState = savedState; + continue; } - statePtr->inputEncodingState = oldState; - Tcl_ExternalToUtf(NULL, statePtr->encoding, src, srcLen, - statePtr->inputEncodingFlags, &statePtr->inputEncodingState, - dst, dstRead + TCL_UTF_MAX, &srcRead, &dstWrote, &numChars); - TranslateInputEOL(statePtr, dst, dst, &dstWrote, &dstRead); - } - /* - * The number of characters that we got may be less than the number that - * we started with because "\r\n" sequences may have been turned into just - * '\n' in dst. - */ + if (dstWrote == 0) { + ChannelBuffer *nextPtr; - numChars -= dstRead - dstWrote; + /* We were not able to read any chars. */ - if ((unsigned) numChars > (unsigned) toRead) { - /* - * Got too many chars. - */ + assert (numChars == 0); - const char *eof = Tcl_UtfAtIndex(dst, toRead); + /* + * There is one situation where this is the correct final + * result. If the src buffer contains only a single \n + * byte, and we are in TCL_TRANSLATE_AUTO mode, and + * when the translation pass was made the INPUT_SAW_CR + * flag was set on the channel. In that case, the + * correct behavior is to consume that \n and produce the + * empty string. + */ - statePtr->inputEncodingState = oldState; - Tcl_ExternalToUtf(NULL, statePtr->encoding, src, srcLen, - statePtr->inputEncodingFlags, &statePtr->inputEncodingState, - dst, eof - dst + TCL_UTF_MAX, &srcRead, &dstWrote, &numChars); - dstRead = dstWrote; - TranslateInputEOL(statePtr, dst, dst, &dstWrote, &dstRead); - numChars -= (dstRead - dstWrote); - } - statePtr->inputEncodingFlags &= ~TCL_ENCODING_START; + if (dstRead == 1 && dst[0] == '\n') { + assert(statePtr->inputTranslation == TCL_TRANSLATE_AUTO); + + goto consume; + } - bufPtr->nextRemoved += srcRead; - if (dstWrote > srcRead + 1) { - *factorPtr = dstWrote * UTF_EXPANSION_FACTOR / srcRead; + /* Otherwise, reading zero characters indicates there's + * something incomplete at the end of the src buffer. + * Maybe there were not enough src bytes to decode into + * a char. Maybe a lone \r could not be translated (crlf + * mode). Need to combine any unused src bytes we have + * in the first buffer with subsequent bytes to try again. + */ + + nextPtr = bufPtr->nextPtr; + + if (nextPtr == NULL) { + if (srcLen > 0) { + SetFlag(statePtr, CHANNEL_NEED_MORE_DATA); + } + Tcl_SetObjLength(objPtr, numBytes); + return -1; + } + + /* + * Space is made at the beginning of the buffer to copy the + * previous unused bytes there. Check first if the buffer we + * are using actually has enough space at its beginning for + * the data we are copying. Because if not we will write over + * the buffer management information, especially the 'nextPtr'. + * + * Note that the BUFFER_PADDING (See AllocChannelBuffer) is + * used to prevent exactly this situation. I.e. it should never + * happen. Therefore it is ok to panic should it happen despite + * the precautions. + */ + + if (nextPtr->nextRemoved - srcLen < 0) { + Tcl_Panic("Buffer Underflow, BUFFER_PADDING not enough"); + } + + nextPtr->nextRemoved -= srcLen; + memcpy(RemovePoint(nextPtr), src, (size_t) srcLen); + RecycleBuffer(statePtr, bufPtr, 0); + statePtr->inQueueHead = nextPtr; + Tcl_SetObjLength(objPtr, numBytes); + return ReadChars(statePtr, objPtr, charsToRead, factorPtr); + } + + statePtr->inputEncodingFlags &= ~TCL_ENCODING_START; + + consume: + bufPtr->nextRemoved += srcRead; + /* + * If this read contained multibyte characters, revise factorPtr + * so the next read will allocate bigger buffers. + */ + if (numChars && numChars < srcRead) { + *factorPtr = srcRead * UTF_EXPANSION_FACTOR / numChars; + } + Tcl_SetObjLength(objPtr, numBytes + dstWrote); + return numChars; } - *offsetPtr += dstWrote; - return numChars; } /* @@ -6087,7 +6331,7 @@ ReadChars( *--------------------------------------------------------------------------- */ -static int +static void TranslateInputEOL( ChannelState *statePtr, /* Channel being read, for EOL translation and * EOF character. */ @@ -6096,132 +6340,138 @@ TranslateInputEOL( * characters. */ const char *srcStart, /* Source characters. */ int *dstLenPtr, /* On entry, the maximum length of output - * buffer in bytes; must be <= *srcLenPtr. On - * exit, the number of bytes actually used in - * output buffer. */ + * buffer in bytes. On exit, the number of + * bytes actually used in output buffer. */ int *srcLenPtr) /* On entry, the length of source buffer. On * exit, the number of bytes read from the * source buffer. */ { - int dstLen, srcLen, inEofChar; - const char *eof; + const char *eof = NULL; + int dstLen = *dstLenPtr; + int srcLen = *srcLenPtr; + int inEofChar = statePtr->inEofChar; - dstLen = *dstLenPtr; + /* + * Depending on the translation mode in use, there's no need + * to scan more srcLen bytes at srcStart than can possibly transform + * to dstLen bytes. This keeps the scan for eof char below from + * being pointlessly long. + */ + + switch (statePtr->inputTranslation) { + case TCL_TRANSLATE_LF: + case TCL_TRANSLATE_CR: + if (srcLen > dstLen) { + /* In these modes, each src byte become a dst byte. */ + srcLen = dstLen; + } + break; + default: + /* In other modes, at most 2 src bytes become a dst byte. */ + if (srcLen > 2 * dstLen) { + srcLen = 2 * dstLen; + } + break; + } - eof = NULL; - inEofChar = statePtr->inEofChar; if (inEofChar != '\0') { /* - * Find EOF in translated buffer then compress out the EOL. The source - * buffer may be much longer than the destination buffer - we only - * want to return EOF if the EOF has been copied to the destination - * buffer. + * Make sure we do not read past any logical end of channel input + * created by the presence of the input eof char. */ - const char *src, *srcMax = srcStart + *srcLenPtr; - - for (src = srcStart; src < srcMax; src++) { - if (*src == inEofChar) { - eof = src; - srcLen = src - srcStart; - if (srcLen < dstLen) { - dstLen = srcLen; - } - *srcLenPtr = srcLen; - break; - } + if ((eof = memchr(srcStart, inEofChar, srcLen))) { + srcLen = eof - srcStart; } } + switch (statePtr->inputTranslation) { case TCL_TRANSLATE_LF: + case TCL_TRANSLATE_CR: if (dstStart != srcStart) { - memcpy(dstStart, srcStart, (size_t) dstLen); + memcpy(dstStart, srcStart, (size_t) srcLen); } - srcLen = dstLen; - break; - case TCL_TRANSLATE_CR: { - char *dst, *dstEnd; + if (statePtr->inputTranslation == TCL_TRANSLATE_CR) { + char *dst = dstStart; + char *dstEnd = dstStart + srcLen; - if (dstStart != srcStart) { - memcpy(dstStart, srcStart, (size_t) dstLen); - } - dstEnd = dstStart + dstLen; - for (dst = dstStart; dst < dstEnd; dst++) { - if (*dst == '\r') { - *dst = '\n'; + while ((dst = memchr(dst, '\r', dstEnd - dst))) { + *dst++ = '\n'; } } - srcLen = dstLen; + dstLen = srcLen; break; - } case TCL_TRANSLATE_CRLF: { - char *dst; - const char *src, *srcEnd, *srcMax; - - dst = dstStart; - src = srcStart; - srcEnd = srcStart + dstLen; - srcMax = srcStart + *srcLenPtr; - - for ( ; src < srcEnd; ) { - if (*src == '\r') { - src++; - if (src >= srcMax) { - SetFlag(statePtr, INPUT_NEED_NL); - } else if (*src == '\n') { - *dst++ = *src++; - } else { + const char *crFound, *src = srcStart; + char *dst = dstStart; + int lesser = (dstLen < srcLen) ? dstLen : srcLen; + + while ((crFound = memchr(src, '\r', lesser))) { + int numBytes = crFound - src; + memmove(dst, src, numBytes); + + dst += numBytes; dstLen -= numBytes; + src += numBytes; srcLen -= numBytes; + if (srcLen == 1) { + /* valid src bytes end in \r */ + if (eof) { *dst++ = '\r'; + src++; srcLen--; + } else { + lesser = 0; + break; } + } else if (src[1] == '\n') { + *dst++ = '\n'; + src += 2; srcLen -= 2; } else { - *dst++ = *src++; + *dst++ = '\r'; + src++; srcLen--; } + dstLen--; + lesser = (dstLen < srcLen) ? dstLen : srcLen; } - srcLen = src - srcStart; - dstLen = dst - dstStart; + memmove(dst, src, lesser); + srcLen = src + lesser - srcStart; + dstLen = dst + lesser - dstStart; break; } case TCL_TRANSLATE_AUTO: { - char *dst; - const char *src, *srcEnd, *srcMax; + const char *crFound, *src = srcStart; + char *dst = dstStart; + int lesser; - dst = dstStart; - src = srcStart; - srcEnd = srcStart + dstLen; - srcMax = srcStart + *srcLenPtr; - - if (GotFlag(statePtr, INPUT_SAW_CR) && (src < srcMax)) { - if (*src == '\n') { - src++; - } + if ((statePtr->flags & INPUT_SAW_CR) && srcLen) { + if (*src == '\n') { src++; srcLen--; } ResetFlag(statePtr, INPUT_SAW_CR); } - for ( ; src < srcEnd; ) { - if (*src == '\r') { - src++; - if (src >= srcMax) { - SetFlag(statePtr, INPUT_SAW_CR); - } else if (*src == '\n') { - if (srcEnd < srcMax) { - srcEnd++; - } - src++; - } - *dst++ = '\n'; - } else { - *dst++ = *src++; + lesser = (dstLen < srcLen) ? dstLen : srcLen; + while ((crFound = memchr(src, '\r', lesser))) { + int numBytes = crFound - src; + memmove(dst, src, numBytes); + + dst[numBytes] = '\n'; + dst += numBytes + 1; dstLen -= numBytes + 1; + src += numBytes + 1; srcLen -= numBytes + 1; + if (srcLen == 0) { + SetFlag(statePtr, INPUT_SAW_CR); + } else if (*src == '\n') { + src++; srcLen--; } + lesser = (dstLen < srcLen) ? dstLen : srcLen; } - srcLen = src - srcStart; - dstLen = dst - dstStart; + memmove(dst, src, lesser); + srcLen = src + lesser - srcStart; + dstLen = dst + lesser - dstStart; break; } default: - return 0; + Tcl_Panic("unknown input translation %d", statePtr->inputTranslation); } *dstLenPtr = dstLen; + *srcLenPtr = srcLen; - if ((eof != NULL) && (srcStart + srcLen >= eof)) { + if (srcStart + srcLen == eof) { /* * EOF character was seen in EOL translated range. Leave current file * position pointing at the EOF character, but don't store the EOF @@ -6230,12 +6480,8 @@ TranslateInputEOL( SetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF); statePtr->inputEncodingFlags |= TCL_ENCODING_END; - ResetFlag(statePtr, INPUT_SAW_CR | INPUT_NEED_NL); - return 1; + ResetFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR); } - - *srcLenPtr = srcLen; - return 0; } /* @@ -6289,16 +6535,15 @@ Tcl_Ungets( statePtr->flags = flags; /* - * If we have encountered a sticky EOF, just punt without storing (sticky - * EOF is set if we have seen the input eofChar, to prevent reading beyond - * the eofChar). Otherwise, clear the EOF flags, and clear the BLOCKED - * bit. We want to discover these conditions anew in each operation. + * Clear the EOF flags, and clear the BLOCKED bit. */ - - if (GotFlag(statePtr, CHANNEL_STICKY_EOF)) { - goto done; + + if (GotFlag(statePtr, CHANNEL_EOF)) { + statePtr->inputEncodingFlags |= TCL_ENCODING_START; } - ResetFlag(statePtr, CHANNEL_BLOCKED | CHANNEL_EOF); + ResetFlag(statePtr, + CHANNEL_BLOCKED | CHANNEL_STICKY_EOF | CHANNEL_EOF | INPUT_SAW_CR); + statePtr->inputEncodingFlags &= ~TCL_ENCODING_END; bufPtr = AllocChannelBuffer(len); memcpy(InsertPoint(bufPtr), str, (size_t) len); @@ -6363,14 +6608,6 @@ Tcl_Flush( return -1; } - /* - * Force current output buffer to be output also. - */ - - if ((statePtr->curOutPtr != NULL) && IsBufferReady(statePtr->curOutPtr)) { - SetFlag(statePtr, BUFFER_READY); - } - result = FlushChannel(NULL, chanPtr, 0); if (result != 0) { return TCL_ERROR; @@ -6433,6 +6670,9 @@ DiscardInputQueued( * * Reads input data from a device into a channel buffer. * + * IMPORTANT! This routine is only called on a chanPtr argument + * that is the top channel of a stack! + * * Results: * The return value is the Posix error code if an error occurred while * reading from the file, or 0 otherwise. @@ -6454,6 +6694,14 @@ GetInput( ChannelState *statePtr = chanPtr->state; /* State info for channel */ + /* + * Verify that all callers know better than to call us when + * it's recorded that the next char waiting to be read is the + * eofchar. + */ + + assert( !GotFlag(statePtr, CHANNEL_STICKY_EOF) ); + /* * Prevent reading from a dead channel -- a channel that has been closed * but not yet deallocated, which can happen if the exit handler for @@ -6466,20 +6714,34 @@ GetInput( } /* + * WARNING: There was once a comment here claiming that it was + * a bad idea to make another call to the inputproc of a channel + * driver when EOF has already been detected on the channel. Through + * much of Tcl's history, this warning was then completely negated + * by having all (most?) read paths clear the EOF setting before + * reaching here. So we had a guard that was never triggered. + * + * Don't be tempted to restore the guard. Even if EOF is set on + * the channel, continue through and call the inputproc again. This + * is the way to enable the ability to [read] again beyond the EOF, + * which seems a strange thing to do, but for which use cases exist + * [Tcl Bug 5adc350683] and which may even be essential for channels + * representing things like ttys or other devices where the stream + * might take the logical form of a series of 'files' separated by + * an EOF condition. + */ + + /* * First check for more buffers in the pushback area of the topmost * channel in the stack and use them. They can be the result of a * transformation which went away without reading all the information * placed in the area when it was stacked. - * - * Two possibilities for the state: No buffers in it, or a single empty - * buffer. In the latter case we can recycle it now. */ if (chanPtr->inQueueHead != NULL) { - if (statePtr->inQueueHead != NULL) { - RecycleBuffer(statePtr, statePtr->inQueueHead, 0); - statePtr->inQueueHead = NULL; - } + + /* TODO: Tests to cover this. */ + assert(statePtr->inQueueHead == NULL); statePtr->inQueueHead = chanPtr->inQueueHead; statePtr->inQueueTail = chanPtr->inQueueTail; @@ -6500,20 +6762,20 @@ GetInput( */ bufPtr = statePtr->inQueueTail; - if ((bufPtr != NULL) && !IsBufferFull(bufPtr)) { - toRead = SpaceLeft(bufPtr); - } else { + + if ((bufPtr == NULL) || IsBufferFull(bufPtr)) { bufPtr = statePtr->saveInBufPtr; statePtr->saveInBufPtr = NULL; /* * Check the actual buffersize against the requested buffersize. - * Buffers which are smaller than requested are squashed. This is done + * Saved buffers of the wrong size are squashed. This is done * to honor dynamic changes of the buffersize made by the user. + * TODO: Tests to cover this. */ if ((bufPtr != NULL) - && (bufPtr->bufLength - BUFFER_PADDING < statePtr->bufSize)) { + && (bufPtr->bufLength - BUFFER_PADDING != statePtr->bufSize)) { ReleaseChannelBuffer(bufPtr); bufPtr = NULL; } @@ -6523,21 +6785,8 @@ GetInput( } bufPtr->nextPtr = NULL; - /* - * SF #427196: Use the actual size of the buffer to determine the - * number of bytes to read from the channel and not the size for new - * buffers. They can be different if the buffersize was changed - * between reads. - * - * Note: This affects performance negatively if the buffersize was - * extended but this small buffer is reused for all subsequent reads. - * The system never uses buffers with the requested bigger size in - * that case. An adjunct patch could try and delete all unused buffers - * it encounters and which are smaller than the formally requested - * buffersize. - */ - toRead = SpaceLeft(bufPtr); + assert(toRead == statePtr->bufSize); if (statePtr->inQueueTail == NULL) { statePtr->inQueueHead = bufPtr; @@ -6545,76 +6794,20 @@ GetInput( statePtr->inQueueTail->nextPtr = bufPtr; } statePtr->inQueueTail = bufPtr; + } else { + toRead = SpaceLeft(bufPtr); } - /* - * If EOF is set, we should avoid calling the driver because on some - * platforms it is impossible to read from a device after EOF. - */ - - if (GotFlag(statePtr, CHANNEL_EOF)) { - return 0; - } - -#ifdef TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING - /* - * [Bug 943274]: Better emulation of non-blocking channels for channels - * without BlockModeProc, by keeping track of true fileevents generated by - * the OS == Data waiting and reading if and only if we are sure to have - * data. - */ - - if (GotFlag(statePtr, CHANNEL_NONBLOCKING) && - (Tcl_ChannelBlockModeProc(chanPtr->typePtr) == NULL) && - !GotFlag(statePtr, CHANNEL_HAS_MORE_DATA)) { - /* - * Bypass the driver, it would block, as no data is available - */ - - nread = -1; - result = EWOULDBLOCK; - } else -#endif /* TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING */ - { - PreserveChannelBuffer(bufPtr); - nread = ChanRead(chanPtr, InsertPoint(bufPtr), toRead, &result); - } + PreserveChannelBuffer(bufPtr); + nread = ChanRead(chanPtr, InsertPoint(bufPtr), toRead); - if (nread > 0) { + if (nread < 0) { + result = Tcl_GetErrno(); + } else { result = 0; bufPtr->nextAdded += nread; - - /* - * If we get a short read, signal up that we may be BLOCKED. We should - * avoid calling the driver because on some platforms we will block in - * the low level reading code even though the channel is set into - * nonblocking mode. - */ - - if (nread < toRead) { - SetFlag(statePtr, CHANNEL_BLOCKED); - } - -#ifdef TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING - if (nread <= toRead) { - /* - * [Bug 943274]: We have read the available data, clear flag. - */ - - ResetFlag(statePtr, CHANNEL_HAS_MORE_DATA); - } -#endif /* TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING */ - } else if (nread == 0) { - result = 0; - SetFlag(statePtr, CHANNEL_EOF); - statePtr->inputEncodingFlags |= TCL_ENCODING_END; - } else if (nread < 0) { - if ((result == EWOULDBLOCK) || (result == EAGAIN)) { - SetFlag(statePtr, CHANNEL_BLOCKED); - result = EAGAIN; - } - Tcl_SetErrno(result); } + ReleaseChannelBuffer(bufPtr); return result; } @@ -6720,8 +6913,12 @@ Tcl_Seek( * point. Also clear CR related flags. */ + if (GotFlag(statePtr, CHANNEL_EOF)) { + statePtr->inputEncodingFlags |= TCL_ENCODING_START; + } ResetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF | CHANNEL_BLOCKED | INPUT_SAW_CR); + statePtr->inputEncodingFlags &= ~TCL_ENCODING_END; /* * If the channel is in asynchronous output mode, switch it back to @@ -6744,15 +6941,6 @@ Tcl_Seek( } /* - * If there is data buffered in statePtr->curOutPtr then mark the channel - * as ready to flush before invoking FlushChannel. - */ - - if ((statePtr->curOutPtr != NULL) && IsBufferReady(statePtr->curOutPtr)) { - SetFlag(statePtr, BUFFER_READY); - } - - /* * 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 @@ -7035,17 +7223,7 @@ CheckChannelErrors( } if (direction == TCL_READABLE) { - /* - * If we have not encountered a sticky EOF, clear the EOF bit (sticky - * EOF is set if we have seen the input eofChar, to prevent reading - * beyond the eofChar). Also, always clear the BLOCKED bit. We want to - * discover these conditions anew in each operation. - */ - - if (!GotFlag(statePtr, CHANNEL_STICKY_EOF)) { - ResetFlag(statePtr, CHANNEL_EOF); - } - ResetFlag(statePtr, CHANNEL_BLOCKED | CHANNEL_NEED_MORE_DATA); + ResetFlag(statePtr, CHANNEL_NEED_MORE_DATA); } return 0; @@ -7074,9 +7252,7 @@ Tcl_Eof( ChannelState *statePtr = ((Channel *) chan)->state; /* State of real channel structure. */ - return (GotFlag(statePtr, CHANNEL_STICKY_EOF) || - (GotFlag(statePtr, CHANNEL_EOF) && - (Tcl_InputBuffered(chan) == 0))) ? 1 : 0; + return GotFlag(statePtr, CHANNEL_EOF) ? 1 : 0; } /* @@ -7261,7 +7437,27 @@ Tcl_SetChannelBufferSize( } statePtr = ((Channel *) chan)->state; + + if (statePtr->bufSize == sz) { + return; + } statePtr->bufSize = sz; + + /* + * If bufsize changes, need to get rid of old utility buffer. + */ + + if (statePtr->saveInBufPtr != NULL) { + RecycleBuffer(statePtr, statePtr->saveInBufPtr, 1); + statePtr->saveInBufPtr = NULL; + } + if ((statePtr->inQueueHead != NULL) + && (statePtr->inQueueHead->nextPtr == NULL) + && IsBufferEmpty(statePtr->inQueueHead)) { + RecycleBuffer(statePtr, statePtr->inQueueHead, 1); + statePtr->inQueueHead = NULL; + statePtr->inQueueTail = NULL; + } } /* @@ -7696,6 +7892,7 @@ Tcl_SetChannelOption( return TCL_ERROR; } Tcl_SetChannelBufferSize(chan, newBufferSize); + return TCL_OK; } else if (HaveOpt(2, "-encoding")) { Tcl_Encoding encoding; @@ -7727,6 +7924,7 @@ Tcl_SetChannelOption( statePtr->outputEncodingFlags = TCL_ENCODING_START; ResetFlag(statePtr, CHANNEL_NEED_MORE_DATA); UpdateInterest(chanPtr); + return TCL_OK; } else if (HaveOpt(2, "-eofchar")) { if (Tcl_SplitList(interp, newValue, &argc, &argv) == TCL_ERROR) { return TCL_ERROR; @@ -7773,7 +7971,11 @@ Tcl_SetChannelOption( * ahead'. Ditto for blocked. */ + if (GotFlag(statePtr, CHANNEL_EOF)) { + statePtr->inputEncodingFlags |= TCL_ENCODING_START; + } ResetFlag(statePtr, CHANNEL_EOF|CHANNEL_STICKY_EOF|CHANNEL_BLOCKED); + statePtr->inputEncodingFlags &= ~TCL_ENCODING_END; return TCL_OK; } else if (HaveOpt(1, "-translation")) { const char *readMode, *writeMode; @@ -7887,22 +8089,6 @@ Tcl_SetChannelOption( return Tcl_BadChannelOption(interp, optionName, NULL); } - /* - * If bufsize changes, need to get rid of old utility buffer. - */ - - if (statePtr->saveInBufPtr != NULL) { - RecycleBuffer(statePtr, statePtr->saveInBufPtr, 1); - statePtr->saveInBufPtr = NULL; - } - if ((statePtr->inQueueHead != NULL) - && (statePtr->inQueueHead->nextPtr == NULL) - && IsBufferEmpty(statePtr->inQueueHead)) { - RecycleBuffer(statePtr, statePtr->inQueueHead, 1); - statePtr->inQueueHead = NULL; - statePtr->inQueueTail = NULL; - } - return TCL_OK; } @@ -7994,21 +8180,6 @@ Tcl_NotifyChannel( Channel *upChanPtr; const Tcl_ChannelType *upTypePtr; -#ifdef TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING - /* - * [SF Tcl Bug 943274] For a non-blocking channel without blockmodeproc we - * keep track of actual input coming from the OS so that we can do a - * credible imitation of non-blocking behaviour. - */ - - if ((mask & TCL_READABLE) && - GotFlag(statePtr, CHANNEL_NONBLOCKING) && - (Tcl_ChannelBlockModeProc(chanPtr->typePtr) == NULL) && - !GotFlag(statePtr, CHANNEL_TIMER_FEV)) { - SetFlag(statePtr, CHANNEL_HAS_MORE_DATA); - } -#endif /* TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING */ - /* * In contrast to the other API functions this procedure walks towards the * top of a stack and not down from it. @@ -8058,7 +8229,7 @@ Tcl_NotifyChannel( * Preserve the channel struct in case the script closes it. */ - Tcl_Preserve(channel); + TclChannelPreserve((Tcl_Channel)channel); Tcl_Preserve(statePtr); /* @@ -8068,13 +8239,14 @@ Tcl_NotifyChannel( */ if (GotFlag(statePtr, BG_FLUSH_SCHEDULED) && (mask & TCL_WRITABLE)) { - FlushChannel(NULL, chanPtr, 1); - mask &= ~TCL_WRITABLE; + if (0 == FlushChannel(NULL, chanPtr, 1)) { + mask &= ~TCL_WRITABLE; + } } /* * Add this invocation to the list of recursive invocations of - * ChannelHandlerEventProc. + * Tcl_NotifyChannel. */ nh.nextHandlerPtr = NULL; @@ -8089,7 +8261,7 @@ Tcl_NotifyChannel( if ((chPtr->mask & mask) != 0) { nh.nextHandlerPtr = chPtr->nextPtr; - chPtr->proc(chPtr->clientData, mask); + chPtr->proc(chPtr->clientData, chPtr->mask & mask); chPtr = nh.nextHandlerPtr; } else { chPtr = chPtr->nextPtr; @@ -8107,7 +8279,7 @@ Tcl_NotifyChannel( } Tcl_Release(statePtr); - Tcl_Release(channel); + TclChannelRelease(channel); tsdPtr->nestedHandlerPtr = nh.nestedHandlerPtr; } @@ -8249,29 +8421,8 @@ ChannelTimerProc( statePtr->timer = Tcl_CreateTimerHandler(SYNTHETIC_EVENT_TIME, ChannelTimerProc,chanPtr); - -#ifdef TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING - /* - * Set the TIMER flag to notify the higher levels that the driver - * might have no data for us. We do this only if we are in - * non-blocking mode and the driver has no BlockModeProc because only - * then we really don't know if the driver will block or not. A - * similar test is done in "PeekAhead". - */ - - if (GotFlag(statePtr, CHANNEL_NONBLOCKING) && - (Tcl_ChannelBlockModeProc(chanPtr->typePtr) == NULL)) { - SetFlag(statePtr, CHANNEL_TIMER_FEV); - } -#endif /* TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING */ - Tcl_Preserve(statePtr); Tcl_NotifyChannel((Tcl_Channel) chanPtr, TCL_READABLE); - -#ifdef TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING - ResetFlag(statePtr, CHANNEL_TIMER_FEV); -#endif /* TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING */ - Tcl_Release(statePtr); } else { statePtr->timer = NULL; @@ -8414,7 +8565,7 @@ Tcl_DeleteChannelHandler( } /* - * If ChannelHandlerEventProc is about to process this handler, tell it to + * If Tcl_NotifyChannel is about to process this handler, tell it to * process the next one instead - we are going to delete *this* one. */ @@ -8610,7 +8761,7 @@ TclChannelEventScriptInvoker( */ Tcl_Preserve(interp); - Tcl_Preserve(chanPtr); + TclChannelPreserve((Tcl_Channel)chanPtr); result = Tcl_EvalObjEx(interp, esPtr->scriptPtr, TCL_EVAL_GLOBAL); /* @@ -8627,7 +8778,7 @@ TclChannelEventScriptInvoker( } Tcl_BackgroundException(interp, result); } - Tcl_Release(chanPtr); + TclChannelRelease((Tcl_Channel)chanPtr); Tcl_Release(interp); } @@ -8790,6 +8941,7 @@ TclCopyChannel( int readFlags, writeFlags; CopyState *csPtr; int nonBlocking = (cmdPtr) ? CHANNEL_NONBLOCKING : 0; + int moveBytes; inStatePtr = inPtr->state; outStatePtr = outPtr->state; @@ -8841,13 +8993,24 @@ TclCopyChannel( | CHANNEL_UNBUFFERED; /* + * Test for conditions where we know we can just move bytes from input + * channel to output channel with no transformation or even examination + * of the bytes themselves. + */ + + moveBytes = inStatePtr->inEofChar == '\0' /* No eofChar to stop input */ + && inStatePtr->inputTranslation == TCL_TRANSLATE_LF + && outStatePtr->outputTranslation == TCL_TRANSLATE_LF + && inStatePtr->encoding == outStatePtr->encoding; + + /* * Allocate a new CopyState to maintain info about the current copy in * progress. This structure will be deallocated when the copy is * completed. */ - csPtr = ckalloc(sizeof(CopyState) + inStatePtr->bufSize); - csPtr->bufSize = inStatePtr->bufSize; + csPtr = ckalloc(sizeof(CopyState) + !moveBytes * inStatePtr->bufSize); + csPtr->bufSize = !moveBytes * inStatePtr->bufSize; csPtr->readPtr = inPtr; csPtr->writePtr = outPtr; csPtr->readFlags = readFlags; @@ -8863,6 +9026,10 @@ TclCopyChannel( inStatePtr->csPtrR = csPtr; outStatePtr->csPtrW = csPtr; + if (moveBytes) { + return MoveBytes(csPtr); + } + /* * Special handling of -size 0 async transfers, so that the -command is * still called asynchronously. @@ -8897,6 +9064,236 @@ TclCopyChannel( *---------------------------------------------------------------------- */ +static void +MBCallback( + CopyState *csPtr, + Tcl_Obj *errObj) +{ + Tcl_Obj *cmdPtr = Tcl_DuplicateObj(csPtr->cmdPtr); + Tcl_WideInt total = csPtr->total; + Tcl_Interp *interp = csPtr->interp; + int code; + + Tcl_IncrRefCount(cmdPtr); + StopCopy(csPtr); + + /* TODO: What if cmdPtr is not a list?! */ + + Tcl_ListObjAppendElement(NULL, cmdPtr, Tcl_NewWideIntObj(total)); + if (errObj) { + Tcl_ListObjAppendElement(NULL, cmdPtr, errObj); + } + + Tcl_Preserve(interp); + code = Tcl_EvalObjEx(interp, cmdPtr, TCL_EVAL_GLOBAL); + if (code != TCL_OK) { + Tcl_BackgroundException(interp, code); + } + Tcl_Release(interp); + TclDecrRefCount(cmdPtr); +} + +static void +MBError( + CopyState *csPtr, + int mask, + int errorCode) +{ + Tcl_Channel inChan = (Tcl_Channel) csPtr->readPtr; + Tcl_Channel outChan = (Tcl_Channel) csPtr->writePtr; + Tcl_Obj *errObj; + + Tcl_SetErrno(errorCode); + + errObj = Tcl_ObjPrintf( "error %sing \"%s\": %s", + (mask & TCL_READABLE) ? "read" : "writ", + Tcl_GetChannelName((mask & TCL_READABLE) ? inChan : outChan), + Tcl_PosixError(csPtr->interp)); + + if (csPtr->cmdPtr) { + MBCallback(csPtr, errObj); + } else { + Tcl_SetObjResult(csPtr->interp, errObj); + StopCopy(csPtr); + } +} + +static void +MBEvent( + ClientData clientData, + int mask) +{ + CopyState *csPtr = (CopyState *) clientData; + Tcl_Channel inChan = (Tcl_Channel) csPtr->readPtr; + Tcl_Channel outChan = (Tcl_Channel) csPtr->writePtr; + ChannelState *inStatePtr = csPtr->readPtr->state; + + if (mask & TCL_WRITABLE) { + Tcl_DeleteChannelHandler(inChan, MBEvent, csPtr); + Tcl_DeleteChannelHandler(outChan, MBEvent, csPtr); + switch (MBWrite(csPtr)) { + case TCL_OK: + MBCallback(csPtr, NULL); + break; + case TCL_CONTINUE: + Tcl_CreateChannelHandler(inChan, TCL_READABLE, MBEvent, csPtr); + break; + } + } else if (mask & TCL_READABLE) { + if (TCL_OK == MBRead(csPtr)) { + /* When at least one full buffer is present, stop reading. */ + if (IsBufferFull(inStatePtr->inQueueHead) + || !Tcl_InputBlocked(inChan)) { + Tcl_DeleteChannelHandler(inChan, MBEvent, csPtr); + } + + /* Successful read -- set up to write the bytes we read */ + Tcl_CreateChannelHandler(outChan, TCL_WRITABLE, MBEvent, csPtr); + } + } +} + +static int +MBRead( + CopyState *csPtr) +{ + ChannelState *inStatePtr = csPtr->readPtr->state; + ChannelBuffer *bufPtr = inStatePtr->inQueueHead; + int code; + + if (bufPtr && BytesLeft(bufPtr) > 0) { + return TCL_OK; + } + + code = GetInput(inStatePtr->topChanPtr); + if (code == 0 || GotFlag(inStatePtr, CHANNEL_BLOCKED)) { + return TCL_OK; + } else { + MBError(csPtr, TCL_READABLE, code); + return TCL_ERROR; + } +} + +static int +MBWrite( + CopyState *csPtr) +{ + ChannelState *inStatePtr = csPtr->readPtr->state; + ChannelState *outStatePtr = csPtr->writePtr->state; + ChannelBuffer *bufPtr = inStatePtr->inQueueHead; + ChannelBuffer *tail = NULL; + int code; + Tcl_WideInt inBytes = 0; + + /* Count up number of bytes waiting in the input queue */ + while (bufPtr) { + inBytes += BytesLeft(bufPtr); + tail = bufPtr; + if (csPtr->toRead != -1 && csPtr->toRead < inBytes) { + /* Queue has enough bytes to complete the copy */ + break; + } + bufPtr = bufPtr->nextPtr; + } + + if (bufPtr) { + /* Split the overflowing buffer in two */ + int extra = (int) (inBytes - csPtr->toRead); + /* Note that going with int for extra assumes that inBytes is not too + * much over toRead to require a wide itself. If that gets violated + * then the calculations involving extra must be made wide too. + * + * Noted with Win32/MSVC debug build treating the warning (possible of + * data in int64 to int conversion) as error. + */ + + bufPtr = AllocChannelBuffer(extra); + + tail->nextAdded -= extra; + memcpy(InsertPoint(bufPtr), InsertPoint(tail), extra); + bufPtr->nextAdded += extra; + bufPtr->nextPtr = tail->nextPtr; + tail->nextPtr = NULL; + inBytes = csPtr->toRead; + } + + /* Update the byte counts */ + if (csPtr->toRead != -1) { + csPtr->toRead -= inBytes; + } + csPtr->total += inBytes; + + /* Move buffers from input to output channels */ + if (outStatePtr->outQueueTail) { + outStatePtr->outQueueTail->nextPtr = inStatePtr->inQueueHead; + } else { + outStatePtr->outQueueHead = inStatePtr->inQueueHead; + } + outStatePtr->outQueueTail = tail; + inStatePtr->inQueueHead = bufPtr; + if (inStatePtr->inQueueTail == tail) { + inStatePtr->inQueueTail = bufPtr; + } + if (bufPtr == NULL) { + inStatePtr->inQueueTail = NULL; + } + + code = FlushChannel(csPtr->interp, outStatePtr->topChanPtr, 0); + if (code) { + MBError(csPtr, TCL_WRITABLE, code); + return TCL_ERROR; + } + if (csPtr->toRead == 0 || GotFlag(inStatePtr, CHANNEL_EOF)) { + return TCL_OK; + } + return TCL_CONTINUE; +} + +static int +MoveBytes( + CopyState *csPtr) /* State of copy operation. */ +{ + ChannelState *outStatePtr = csPtr->writePtr->state; + ChannelBuffer *bufPtr = outStatePtr->curOutPtr; + int errorCode; + + if (bufPtr && BytesLeft(bufPtr)) { + /* If we start with unflushed bytes in the destination + * channel, flush them out of the way first. */ + + errorCode = FlushChannel(csPtr->interp, outStatePtr->topChanPtr, 0); + if (errorCode != 0) { + MBError(csPtr, TCL_WRITABLE, errorCode); + return TCL_ERROR; + } + } + + if (csPtr->cmdPtr) { + Tcl_Channel inChan = (Tcl_Channel) csPtr->readPtr; + Tcl_CreateChannelHandler(inChan, TCL_READABLE, MBEvent, csPtr); + return TCL_OK; + } + + while (1) { + int code; + + if (TCL_ERROR == MBRead(csPtr)) { + return TCL_ERROR; + } + code = MBWrite(csPtr); + if (code == TCL_OK) { + Tcl_SetObjResult(csPtr->interp, Tcl_NewWideIntObj(csPtr->total)); + StopCopy(csPtr); + return TCL_OK; + } + if (code == TCL_ERROR) { + return TCL_ERROR; + } + /* code == TCL_CONTINUE --> continue the loop */ + } + return TCL_OK; /* Silence compiler warnings */ +} + static int CopyData( CopyState *csPtr, /* State of copy operation. */ @@ -9022,6 +9419,10 @@ CopyData( csPtr); } if (size == 0) { + if (!GotFlag(inStatePtr, CHANNEL_NONBLOCKING)) { + /* We allowed a short read. Keep trying. */ + continue; + } if (bufObj != NULL) { TclDecrRefCount(bufObj); bufObj = NULL; @@ -9199,12 +9600,23 @@ CopyData( * * DoRead -- * - * Reads a given number of bytes from a channel. No encoding conversions + * Stores up to "bytesToRead" bytes in memory pointed to by "dst". + * These bytes come from reading the channel "chanPtr" and + * performing the configured translations. No encoding conversions * are applied to the bytes being read. * * Results: - * The number of characters read, or -1 on error. Use Tcl_GetErrno() to - * retrieve the error code for the error that occurred. + * The number of bytes actually stored (<= bytesToRead), + * or -1 if there is an error in reading the channel. Use + * Tcl_GetErrno() to retrieve the error code for the error + * that occurred. + * + * The number of bytes stored can be less than the number + * requested when + * - EOF is reached on the channel; or + * - the channel is non-blocking, and we've read all we can + * without blocking. + * - a channel reading error occurs (and we return -1) * * Side effects: * May cause input to be buffered. @@ -9215,384 +9627,197 @@ CopyData( static int DoRead( Channel *chanPtr, /* The channel from which to read. */ - char *bufPtr, /* Where to store input read. */ - int toRead, /* Maximum number of bytes to read. */ + char *dst, /* Where to store input read. */ + int bytesToRead, /* Maximum number of bytes to read. */ int allowShortReads) /* Allow half-blocking (pipes,sockets) */ { ChannelState *statePtr = chanPtr->state; - /* State info for channel */ - 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. */ + char *p = dst; - /* - * 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. - */ - - Tcl_Preserve(chanPtr); - if (!GotFlag(statePtr, CHANNEL_STICKY_EOF)) { - ResetFlag(statePtr, CHANNEL_EOF); - } - ResetFlag(statePtr, CHANNEL_BLOCKED | CHANNEL_NEED_MORE_DATA); - - for (copied = 0; copied < toRead; copied += copiedNow) { - copiedNow = CopyAndTranslateBuffer(statePtr, bufPtr + copied, - toRead - copied); - if (copiedNow == 0) { - if (GotFlag(statePtr, CHANNEL_EOF)) { - goto done; - } - if (GotFlag(statePtr, CHANNEL_BLOCKED)) { - if (GotFlag(statePtr, CHANNEL_NONBLOCKING)) { - goto done; - } - ResetFlag(statePtr, CHANNEL_BLOCKED); - } - result = GetInput(chanPtr); - if (result != 0) { - if (result != EAGAIN) { - copied = -1; - } - goto done; - } - } else if (allowShortReads) { - copied += copiedNow; - break; - } - } - - ResetFlag(statePtr, CHANNEL_BLOCKED); + assert (bytesToRead >= 0); /* - * Update the notifier state so we don't block while there is still data - * in the buffers. + * Early out when we know a read will get the eofchar. + * + * NOTE: This seems to be a bug. The special handling for + * a zero-char read request ought to come first. As coded + * the EOF due to eofchar has distinguishing behavior from + * the EOF due to reported EOF on the underlying device, and + * that seems undesirable. However recent history indicates + * that new inconsistent behavior in a patchlevel has problems + * too. Keep on keeping on for now. */ - done: - UpdateInterest(chanPtr); - Tcl_Release(chanPtr); - return copied; -} - -/* - *---------------------------------------------------------------------- - * - * CopyAndTranslateBuffer -- - * - * Copy at most one buffer of input to the result space, doing eol - * translations according to mode in effect currently. - * - * Results: - * Number of bytes stored in the result buffer (as opposed to the number - * of bytes read from the channel). May return zero if no input is - * available to be translated. - * - * Side effects: - * Consumes buffered input. May deallocate one buffer. - * - *---------------------------------------------------------------------- - */ - -static int -CopyAndTranslateBuffer( - ChannelState *statePtr, /* Channel state 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? */ -{ - ChannelBuffer *bufPtr; /* The buffer from which to copy bytes. */ - 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? */ - 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 (GotFlag(statePtr, CHANNEL_STICKY_EOF)) { + SetFlag(statePtr, CHANNEL_EOF); + assert( statePtr->inputEncodingFlags & TCL_ENCODING_END ); + assert( !GotFlag(statePtr, CHANNEL_BLOCKED|INPUT_SAW_CR) ); - if (statePtr->inQueueHead == NULL) { + UpdateInterest(chanPtr); return 0; } - bufPtr = statePtr->inQueueHead; - bytesInBuffer = BytesLeft(bufPtr); - copied = 0; - switch (statePtr->inputTranslation) { - case TCL_TRANSLATE_LF: - if (bytesInBuffer == 0) { - return 0; + /* Special handling for zero-char read request. */ + if (bytesToRead == 0) { + if (GotFlag(statePtr, CHANNEL_EOF)) { + statePtr->inputEncodingFlags |= TCL_ENCODING_START; } + ResetFlag(statePtr, CHANNEL_BLOCKED|CHANNEL_EOF); + statePtr->inputEncodingFlags &= ~TCL_ENCODING_END; + UpdateInterest(chanPtr); + return 0; + } + TclChannelPreserve((Tcl_Channel)chanPtr); + while (bytesToRead) { /* - * Copy the current chunk into the result buffer. + * Each pass through the loop is intended to process up to + * one channel buffer. */ - if (bytesInBuffer < space) { - space = bytesInBuffer; - } - memcpy(result, RemovePoint(bufPtr), (size_t) space); - bufPtr->nextRemoved += space; - copied = space; - break; - case TCL_TRANSLATE_CR: { - char *end; - - if (bytesInBuffer == 0) { - return 0; - } + int bytesRead, bytesWritten; + ChannelBuffer *bufPtr = statePtr->inQueueHead; /* - * Copy the current chunk into the result buffer, then replace all \r - * with \n. + * Don't read more data if we have what we need. */ - if (bytesInBuffer < space) { - space = bytesInBuffer; - } - memcpy(result, RemovePoint(bufPtr), (size_t) space); - bufPtr->nextRemoved += space; - copied = space; + while (!bufPtr || /* We got no buffer! OR */ + (!IsBufferFull(bufPtr) && /* Our buffer has room AND */ + (BytesLeft(bufPtr) < bytesToRead) ) ) { + /* Not enough bytes in it + * yet to fill the dst */ + int code; - for (end = result + copied; result < end; result++) { - if (*result == '\r') { - *result = '\n'; - } - } - break; - } - case TCL_TRANSLATE_CRLF: { - char *src, *end, *dst; - int curByte; + moreData: + code = GetInput(chanPtr); + bufPtr = statePtr->inQueueHead; - /* - * If there is a held-back "\r" at EOF, produce it now. - */ + assert (bufPtr != NULL); - if (bytesInBuffer == 0) { - if ((statePtr->flags & (INPUT_SAW_CR | CHANNEL_EOF)) == - (INPUT_SAW_CR | CHANNEL_EOF)) { - result[0] = '\r'; - ResetFlag(statePtr, INPUT_SAW_CR); - return 1; + if (GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED)) { + /* Further reads cannot do any more */ + break; } - return 0; - } - /* - * Copy the current chunk and replace "\r\n" with "\n" (but not - * standalone "\r"!). - */ - - if (bytesInBuffer < space) { - space = bytesInBuffer; - } - memcpy(result, RemovePoint(bufPtr), (size_t) space); - bufPtr->nextRemoved += space; - copied = space; - - end = result + copied; - dst = result; - for (src = result; src < end; src++) { - curByte = *src; - if (curByte == '\n') { - ResetFlag(statePtr, INPUT_SAW_CR); - } else if (GotFlag(statePtr, INPUT_SAW_CR)) { - ResetFlag(statePtr, INPUT_SAW_CR); - *dst = '\r'; - dst++; - } - if (curByte == '\r') { - SetFlag(statePtr, INPUT_SAW_CR); - } else { - *dst = (char) curByte; - dst++; + if (code) { + /* Read error */ + UpdateInterest(chanPtr); + TclChannelRelease((Tcl_Channel)chanPtr); + return -1; } - } - copied = dst - result; - break; - } - case TCL_TRANSLATE_AUTO: { - char *src, *end, *dst; - int curByte; - if (bytesInBuffer == 0) { - return 0; + assert (IsBufferFull(bufPtr)); } - /* - * Loop over the current buffer, converting "\r" and "\r\n" to "\n". - */ + assert (bufPtr != NULL); - if (bytesInBuffer < space) { - space = bytesInBuffer; - } - memcpy(result, RemovePoint(bufPtr), (size_t) space); - bufPtr->nextRemoved += space; - copied = space; - - end = result + copied; - dst = result; - for (src = result; src < end; src++) { - curByte = *src; - if (curByte == '\r') { - SetFlag(statePtr, INPUT_SAW_CR); - *dst = '\n'; - dst++; - } else { - if ((curByte != '\n') || !GotFlag(statePtr, INPUT_SAW_CR)) { - *dst = (char) curByte; - dst++; - } - ResetFlag(statePtr, INPUT_SAW_CR); - } - } - copied = dst - result; - break; - } - default: - Tcl_Panic("unknown eol translation mode"); - } + bytesRead = BytesLeft(bufPtr); + bytesWritten = bytesToRead; - /* - * 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. - */ + TranslateInputEOL(statePtr, p, RemovePoint(bufPtr), + &bytesWritten, &bytesRead); + bufPtr->nextRemoved += bytesRead; + p += bytesWritten; + bytesToRead -= bytesWritten; - if (statePtr->inEofChar != 0) { - for (i = 0; i < copied; i++) { - if (result[i] == (char) statePtr->inEofChar) { - /* - * Set sticky EOF so that no further input is presented to the - * caller. - */ + if (!IsBufferEmpty(bufPtr)) { + /* + * Buffer is not empty. How can that be? + * + * 0) We stopped early because we got all the bytes + * we were seeking. That's fine. + */ - SetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF); - statePtr->inputEncodingFlags |= TCL_ENCODING_END; - copied = i; + if (bytesToRead == 0) { + UpdateInterest(chanPtr); break; } - } - } - /* - * If the current buffer is empty recycle it. - */ - - if (IsBufferEmpty(bufPtr)) { - statePtr->inQueueHead = bufPtr->nextPtr; - if (statePtr->inQueueHead == NULL) { - statePtr->inQueueTail = NULL; - } - RecycleBuffer(statePtr, bufPtr, 0); - } + /* + * 1) We're @EOF because we saw eof char. + */ - /* - * Return the number of characters copied into the result buffer. This may - * be different from the number of bytes consumed, because of EOL - * translations. - */ + if (GotFlag(statePtr, CHANNEL_STICKY_EOF)) { + UpdateInterest(chanPtr); + break; + } - return copied; -} - -/* - *---------------------------------------------------------------------- - * - * CopyBuffer -- - * - * Copy at most one buffer of input to the result space. - * - * Results: - * Number of bytes stored in the result buffer. May return zero if no - * input is available. - * - * Side effects: - * Consumes buffered input. May deallocate one buffer. - * - *---------------------------------------------------------------------- - */ + /* + * 2) The buffer holds a \r while in CRLF translation, + * followed by the end of the buffer. + */ -static int -CopyBuffer( - Channel *chanPtr, /* 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? */ -{ - ChannelBuffer *bufPtr; /* The buffer from which to copy bytes. */ - 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? */ + assert(statePtr->inputTranslation == TCL_TRANSLATE_CRLF); + assert(RemovePoint(bufPtr)[0] == '\r'); + assert(BytesLeft(bufPtr) == 1); - /* - * 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 don't leave it in the queue, but - * recycle it. - */ + if (bufPtr->nextPtr == NULL) { + /* There's no more buffered data.... */ - if (chanPtr->inQueueHead == NULL) { - return 0; - } - bufPtr = chanPtr->inQueueHead; - bytesInBuffer = BytesLeft(bufPtr); + if (statePtr->flags & CHANNEL_EOF) { + /* ...and there never will be. */ - copied = 0; + *p++ = '\r'; + bytesToRead--; + bufPtr->nextRemoved++; + } else if (statePtr->flags & CHANNEL_BLOCKED) { + /* ...and we cannot get more now. */ + SetFlag(statePtr, CHANNEL_NEED_MORE_DATA); + UpdateInterest(chanPtr); + break; + } else { + /* ... so we need to get some. */ + goto moreData; + } + } - if (bytesInBuffer == 0) { - RecycleBuffer(chanPtr->state, bufPtr, 0); - chanPtr->inQueueHead = NULL; - chanPtr->inQueueTail = NULL; - return 0; - } + if (bufPtr->nextPtr) { + /* There's a next buffer. Shift orphan \r to it. */ - /* - * Copy the current chunk into the result buffer. - */ + ChannelBuffer *nextPtr = bufPtr->nextPtr; - if (bytesInBuffer < space) { - space = bytesInBuffer; - } + nextPtr->nextRemoved -= 1; + RemovePoint(nextPtr)[0] = '\r'; + bufPtr->nextRemoved++; + } + } - memcpy(result, RemovePoint(bufPtr), (size_t) space); - bufPtr->nextRemoved += space; - copied = space; + if (IsBufferEmpty(bufPtr)) { + statePtr->inQueueHead = bufPtr->nextPtr; + if (statePtr->inQueueHead == NULL) { + statePtr->inQueueTail = NULL; + } + RecycleBuffer(statePtr, bufPtr, 0); + bufPtr = statePtr->inQueueHead; + } - /* - * We don't care about in-stream EOF characters here as the data read here - * may still flow through one or more transformations, i.e. is not in its - * final state yet. - */ + if ((GotFlag(statePtr, CHANNEL_NONBLOCKING) || allowShortReads) + && GotFlag(statePtr, CHANNEL_BLOCKED)) { + break; + } - /* - * If the current buffer is empty recycle it. - */ + /* + * When there's no buffered data to read, and we're at EOF, + * escape to the caller. + */ - if (IsBufferEmpty(bufPtr)) { - chanPtr->inQueueHead = bufPtr->nextPtr; - if (chanPtr->inQueueHead == NULL) { - chanPtr->inQueueTail = NULL; + if (GotFlag(statePtr, CHANNEL_EOF) + && (bufPtr == NULL || IsBufferEmpty(bufPtr))) { + break; } - RecycleBuffer(chanPtr->state, bufPtr, 0); + } + if (bytesToRead == 0) { + ResetFlag(statePtr, CHANNEL_BLOCKED); } - /* - * Return the number of characters copied into the result buffer. - */ - - return copied; + assert(!GotFlag(statePtr, CHANNEL_EOF) + || GotFlag(statePtr, CHANNEL_STICKY_EOF) + || Tcl_InputBuffered((Tcl_Channel)chanPtr) == 0); + assert( !(GotFlag(statePtr, CHANNEL_EOF|CHANNEL_BLOCKED) + == (CHANNEL_EOF|CHANNEL_BLOCKED)) ); + TclChannelRelease((Tcl_Channel)chanPtr); + return (int)(p - dst); } /* @@ -9643,12 +9868,16 @@ StopCopy( CopyState *csPtr) /* State for bg copy to stop . */ { ChannelState *inStatePtr, *outStatePtr; + Tcl_Channel inChan, outChan; + int nonBlocking; if (!csPtr) { return; } + inChan = (Tcl_Channel) csPtr->readPtr; + outChan = (Tcl_Channel) csPtr->writePtr; inStatePtr = csPtr->readPtr->state; outStatePtr = csPtr->writePtr->state; @@ -9673,12 +9902,12 @@ StopCopy( csPtr->writeFlags & (CHANNEL_LINEBUFFERED | CHANNEL_UNBUFFERED); if (csPtr->cmdPtr) { - Tcl_DeleteChannelHandler((Tcl_Channel) csPtr->readPtr, CopyEventProc, - csPtr); - if (csPtr->readPtr != csPtr->writePtr) { - Tcl_DeleteChannelHandler((Tcl_Channel) csPtr->writePtr, - CopyEventProc, csPtr); + Tcl_DeleteChannelHandler(inChan, CopyEventProc, csPtr); + if (inChan != outChan) { + Tcl_DeleteChannelHandler(outChan, CopyEventProc, csPtr); } + Tcl_DeleteChannelHandler(inChan, MBEvent, csPtr); + Tcl_DeleteChannelHandler(outChan, MBEvent, csPtr); TclDecrRefCount(csPtr->cmdPtr); } inStatePtr->csPtrR = NULL; @@ -9712,12 +9941,15 @@ StackSetBlockMode( { int result = 0; Tcl_DriverBlockModeProc *blockModeProc; + ChannelState *statePtr = chanPtr->state; /* * Start at the top of the channel stack + * TODO: Examine what can go wrong when blockModeProc calls + * disturb the stacking state of the channel. */ - chanPtr = chanPtr->state->topChanPtr; + chanPtr = statePtr->topChanPtr; while (chanPtr != NULL) { blockModeProc = Tcl_ChannelBlockModeProc(chanPtr->typePtr); if (blockModeProc != NULL) { @@ -10856,6 +11088,7 @@ SetChannelFromAny( } if (objPtr->typePtr == &chanObjType) { /* + * TODO: TAINT Flag and dup'd channel values? * The channel is valid until any call to DetachChannel occurs. * Ensure consistency checks are done. */ @@ -10932,20 +11165,14 @@ DumpFlags( ChanFlag('n', CHANNEL_NONBLOCKING); ChanFlag('l', CHANNEL_LINEBUFFERED); ChanFlag('u', CHANNEL_UNBUFFERED); - ChanFlag('R', BUFFER_READY); ChanFlag('F', BG_FLUSH_SCHEDULED); ChanFlag('c', CHANNEL_CLOSED); ChanFlag('E', CHANNEL_EOF); ChanFlag('S', CHANNEL_STICKY_EOF); ChanFlag('B', CHANNEL_BLOCKED); ChanFlag('/', INPUT_SAW_CR); - ChanFlag('*', INPUT_NEED_NL); ChanFlag('D', CHANNEL_DEAD); ChanFlag('R', CHANNEL_RAW_MODE); -#ifdef TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING - ChanFlag('T', CHANNEL_TIMER_FEV); - ChanFlag('H', CHANNEL_HAS_MORE_DATA); -#endif /* TCL_IO_TRACK_OS_FOR_DRIVER_WITH_BAD_BLOCKING */ ChanFlag('x', CHANNEL_INCLOSE); buf[i] ='\0'; |