diff options
| -rw-r--r-- | generic/tclIO.c | 124 |
1 files changed, 122 insertions, 2 deletions
diff --git a/generic/tclIO.c b/generic/tclIO.c index d7ed3ac..017494e 100644 --- a/generic/tclIO.c +++ b/generic/tclIO.c @@ -182,6 +182,7 @@ static int CloseChannelPart(Tcl_Interp *interp, Channel *chanPtr, static int CloseWrite(Tcl_Interp *interp, Channel *chanPtr); static void CommonGetsCleanup(Channel *chanPtr); static int CopyData(CopyState *csPtr, int mask); +static int MoveBytes(CopyState *csPtr); static void CopyEventProc(ClientData clientData, int mask); static void CreateScriptRecord(Tcl_Interp *interp, Channel *chanPtr, int mask, Tcl_Obj *scriptPtr); @@ -8778,6 +8779,7 @@ TclCopyChannel( int readFlags, writeFlags; CopyState *csPtr; int nonBlocking = (cmdPtr) ? CHANNEL_NONBLOCKING : 0; + int moveBytes; inStatePtr = inPtr->state; outStatePtr = outPtr->state; @@ -8829,13 +8831,28 @@ TclCopyChannel( | CHANNEL_UNBUFFERED; /* + * Very strict set of 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. + * TODO: Find ways to relax this. + */ + + moveBytes = inStatePtr->inEofChar == '\0' /* No eofChar to stop input */ + && inStatePtr->inputTranslation == TCL_TRANSLATE_LF + && outStatePtr->outputTranslation == TCL_TRANSLATE_LF + && ((inStatePtr->encoding == NULL + && outStatePtr->encoding == NULL) + || (inStatePtr->encoding == outStatePtr->encoding)) + && !nonBlocking; /* First draft do only blocking case */ + + /* * 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; @@ -8851,6 +8868,10 @@ 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. @@ -8886,6 +8907,105 @@ TclCopyChannel( */ static int +MoveBytes( + CopyState *csPtr) /* State of copy operation. */ +{ + ChannelState *inStatePtr = csPtr->readPtr->state; + ChannelState *outStatePtr = csPtr->writePtr->state; + ChannelBuffer *bufPtr = outStatePtr->curOutPtr; + int code = TCL_OK; + + if (bufPtr && BytesLeft(bufPtr)) { + /* If we start with unflushed bytes in the destination + * channel, flush them out of the way first. */ + + if (0 != FlushChannel(csPtr->interp, outStatePtr->topChanPtr, 0)) { + code = TCL_ERROR; + goto done; + } + } + + while (csPtr->toRead != 0) { + ChannelBuffer *bufPtr = inStatePtr->inQueueHead; + ChannelBuffer *tail = NULL; + int inBytes = 0; + + if (bufPtr == NULL || BytesLeft(bufPtr) == 0) { + + /* Nothing in the input queue; Get more input. */ + if (0 != GetInput(inStatePtr->topChanPtr)) { + Tcl_SetObjResult(csPtr->interp, Tcl_ObjPrintf( + "error reading \"%s\": %s", + Tcl_GetChannelName((Tcl_Channel)csPtr->readPtr), + Tcl_PosixError(csPtr->interp))); + code = TCL_ERROR; + break; + } + bufPtr = inStatePtr->inQueueHead; + } + + /* 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 = inBytes - csPtr->toRead; + + 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 (bufPtr == NULL) { + inStatePtr->inQueueTail = NULL; + } + + /* Flush destination */ + if (0 != FlushChannel(csPtr->interp, outStatePtr->topChanPtr, 0)) { + code = TCL_ERROR; + break; + } + if (GotFlag(inStatePtr, CHANNEL_EOF)) { + break; + } + } + + if (code == TCL_OK) { + Tcl_SetObjResult(csPtr->interp, Tcl_NewWideIntObj(csPtr->total)); + } + done: + StopCopy(csPtr); + return code; +} + +static int CopyData( CopyState *csPtr, /* State of copy operation. */ int mask) /* Current channel event flags. */ |