diff options
Diffstat (limited to 'generic/tclIO.c')
| -rw-r--r-- | generic/tclIO.c | 1365 |
1 files changed, 553 insertions, 812 deletions
diff --git a/generic/tclIO.c b/generic/tclIO.c index d69a3d9..c4d9171 100644 --- a/generic/tclIO.c +++ b/generic/tclIO.c @@ -6,11 +6,13 @@ * * 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. */ +#undef NDEBUG #include "tclInt.h" #include "tclIO.h" #include <assert.h> @@ -179,8 +181,6 @@ 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 void CopyEventProc(ClientData clientData, int mask); @@ -194,7 +194,8 @@ 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 +212,16 @@ 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, @@ -1782,17 +1783,17 @@ 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; @@ -2373,12 +2374,12 @@ 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; } @@ -4181,9 +4182,7 @@ 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++; @@ -4988,7 +4987,7 @@ 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 @@ -5050,8 +5049,7 @@ FilterInputBytes( * string rep if we need more space. */ - rawStart = RemovePoint(bufPtr); - raw = rawStart; + raw = RemovePoint(bufPtr); rawLen = BytesLeft(bufPtr); dst = *gsPtr->dstPtr; @@ -5404,39 +5402,18 @@ Tcl_ReadRaw( ResetFlag(statePtr, CHANNEL_BLOCKED); } -#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. + * 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 (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. - */ - - 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. - */ - - nread = ChanRead(chanPtr, bufPtr + copied, - bytesToRead - copied, &result); - } + nread = ChanRead(chanPtr, bufPtr + copied, + bytesToRead - copied, &result); if (nread > 0) { /* @@ -5449,17 +5426,6 @@ Tcl_ReadRaw( 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. - */ - - 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; @@ -5587,8 +5553,9 @@ DoReadChars( ChannelState *statePtr = chanPtr->state; /* State info for channel */ ChannelBuffer *bufPtr; - int offset, factor, copied, copiedNow, result; + int factor, copied, copiedNow, result; Tcl_Encoding encoding; + int binaryMode; #define UTF_EXPANSION_FACTOR 1024 /* @@ -5600,8 +5567,12 @@ DoReadChars( 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); @@ -5610,27 +5581,21 @@ 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); - } } 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); } /* @@ -5679,11 +5644,6 @@ 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 @@ -5719,13 +5679,11 @@ 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. * *--------------------------------------------------------------------------- */ @@ -5738,72 +5696,22 @@ 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; + ChannelBuffer *bufPtr = statePtr->inQueueHead; + int srcLen = BytesLeft(bufPtr); + int toRead = bytesToRead>srcLen || bytesToRead<0 ? srcLen : bytesToRead; - 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--; - } - - 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; } /* @@ -5847,262 +5755,316 @@ 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 dstLimit, numBytes, srcLen = BytesLeft(bufPtr); - factor = *factorPtr; - offset = *offsetPtr; + /* + * 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. + */ - bufPtr = statePtr->inQueueHead; - src = RemovePoint(bufPtr); - srcLen = BytesLeft(bufPtr); - - toRead = charsToRead; - if ((unsigned) toRead > (unsigned) srcLen) { - toRead = srcLen; - } + int toRead = ((unsigned) 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 dstNeeded = 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, dstNeeded); 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; + dstNeeded = 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. + * 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. * - * 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. - * - * 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)) { + dstLimit = dstNeeded + 1; + while (1) { + int dstDecoded, dstRead, dstWrote, srcRead, numChars; + /* - * 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. */ - statePtr->inputEncodingFlags &= ~TCL_ENCODING_END; - encEndFlagSuppressed = 1; - } + int code = Tcl_ExternalToUtf(NULL, encoding, src, srcLen, + statePtr->inputEncodingFlags & (bufPtr->nextPtr + ? ~0 : ~TCL_ENCODING_END), &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 + 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(dstRead + 1 == dstDecoded); + 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 + 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); + assert(dstDecoded == 1); - 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 + 2]; + int read, decoded, count; + + /* + * Didn't get everything the buffer could offer + */ + + statePtr->flags = savedFlags; + statePtr->inputEncodingFlags = savedIEFlags; + statePtr->inputEncodingState = savedState; + + Tcl_ExternalToUtf(NULL, encoding, src, srcLen, + statePtr->inputEncodingFlags & (bufPtr->nextPtr + ? ~0 : ~TCL_ENCODING_END), &statePtr->inputEncodingState, + buffer, TCL_UTF_MAX + 2, &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; + } + + dst[1] = '\0'; + 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; + + /* 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. - */ + /* + * We read more chars than allowed. Reset limits to + * prevent that and try again. + */ - if (dstWrote == 0) { - return -1; + dstLimit = Tcl_UtfAtIndex(dst, charsToRead + 1) - 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) { - numChars -= dstRead - dstWrote; + /* + * We were not able to read any chars. 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. + */ - if ((unsigned) numChars > (unsigned) toRead) { - /* - * Got too many chars. - */ + ChannelBuffer *nextPtr = bufPtr->nextPtr; - const char *eof = Tcl_UtfAtIndex(dst, toRead); + if (nextPtr == NULL) { + if (srcLen > 0) { + SetFlag(statePtr, CHANNEL_NEED_MORE_DATA); + } + Tcl_SetObjLength(objPtr, numBytes); + return -1; + } - 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; + /* + * 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; - bufPtr->nextRemoved += srcRead; - if (dstWrote > srcRead + 1) { - *factorPtr = dstWrote * UTF_EXPANSION_FACTOR / srcRead; + bufPtr->nextRemoved += srcRead; + if (dstWrote > srcRead + 1) { + *factorPtr = dstWrote * UTF_EXPANSION_FACTOR / srcRead; + } + Tcl_SetObjLength(objPtr, numBytes + dstWrote); + return numChars; } - *offsetPtr += dstWrote; - return numChars; } /* @@ -6123,7 +6085,7 @@ ReadChars( *--------------------------------------------------------------------------- */ -static int +static void TranslateInputEOL( ChannelState *statePtr, /* Channel being read, for EOL translation and * EOF character. */ @@ -6132,132 +6094,138 @@ 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 @@ -6266,12 +6234,8 @@ 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, INPUT_SAW_CR); } - - *srcLenPtr = srcLen; - return 0; } /* @@ -6325,16 +6289,11 @@ 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; - } - ResetFlag(statePtr, CHANNEL_BLOCKED | CHANNEL_EOF); + ResetFlag(statePtr, + CHANNEL_BLOCKED | CHANNEL_STICKY_EOF | CHANNEL_EOF | INPUT_SAW_CR); bufPtr = AllocChannelBuffer(len); memcpy(InsertPoint(bufPtr), str, (size_t) len); @@ -6469,6 +6428,9 @@ 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. @@ -6506,16 +6468,11 @@ GetInput( * 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; - } + + assert(statePtr->inQueueHead == NULL); statePtr->inQueueHead = chanPtr->inQueueHead; statePtr->inQueueTail = chanPtr->inQueueTail; @@ -6544,12 +6501,12 @@ GetInput( /* * 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. */ if ((bufPtr != NULL) - && (bufPtr->bufLength - BUFFER_PADDING < statePtr->bufSize)) { + && (bufPtr->bufLength - BUFFER_PADDING != statePtr->bufSize)) { ReleaseChannelBuffer(bufPtr); bufPtr = NULL; } @@ -6559,21 +6516,8 @@ 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; @@ -6584,6 +6528,7 @@ GetInput( } /* + * TODO - consider escape before buffer alloc * If EOF is set, we should avoid calling the driver because on some * platforms it is impossible to read from a device after EOF. */ @@ -6592,30 +6537,8 @@ GetInput( 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, &result); if (nread > 0) { result = 0; bufPtr->nextAdded += nread; @@ -6630,16 +6553,6 @@ GetInput( 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); @@ -7113,15 +7026,10 @@ 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. + * Clear the BLOCKED bit. We want to discover this condition + * anew in each operation. */ - if (!GotFlag(statePtr, CHANNEL_STICKY_EOF)) { - ResetFlag(statePtr, CHANNEL_EOF); - } ResetFlag(statePtr, CHANNEL_BLOCKED | CHANNEL_NEED_MORE_DATA); } @@ -7338,7 +7246,27 @@ 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; + } } /* @@ -7773,6 +7701,7 @@ Tcl_SetChannelOption( return TCL_ERROR; } Tcl_SetChannelBufferSize(chan, newBufferSize); + return TCL_OK; } else if (HaveOpt(2, "-encoding")) { Tcl_Encoding encoding; @@ -7804,6 +7733,7 @@ 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; @@ -7964,22 +7894,6 @@ 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; } @@ -8071,21 +7985,6 @@ 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. @@ -8326,29 +8225,8 @@ 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; @@ -9288,12 +9166,23 @@ 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. @@ -9304,294 +9193,150 @@ 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. */ - - /* - * 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. - */ + char *p = dst; 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); - - /* - * Update the notifier state so we don't block while there is still data - * in the buffers. - */ - - 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 (statePtr->inQueueHead == NULL) { - return 0; - } - bufPtr = statePtr->inQueueHead; - bytesInBuffer = BytesLeft(bufPtr); + while (bytesToRead) { + /* + * Each pass through the loop is intended to process up to + * one channel buffer. + */ - copied = 0; - switch (statePtr->inputTranslation) { - case TCL_TRANSLATE_LF: - if (bytesInBuffer == 0) { - return 0; - } + int bytesRead, bytesWritten; + ChannelBuffer *bufPtr = statePtr->inQueueHead; /* - * Copy the current chunk into the result buffer. + * When there's no buffered data to read, and we're at EOF, + * escape to the caller. */ - if (bytesInBuffer < space) { - space = bytesInBuffer; + if (statePtr->flags & CHANNEL_EOF + && (bufPtr == NULL || IsBufferEmpty(bufPtr))) { + break; } - memcpy(result, RemovePoint(bufPtr), (size_t) space); - bufPtr->nextRemoved += space; - copied = space; - break; - case TCL_TRANSLATE_CR: { - char *end; - if (bytesInBuffer == 0) { - return 0; - } + /* If there is no full buffer, attempt to create and/or fill one. */ - /* - * Copy the current chunk into the result buffer, then replace all \r - * with \n. - */ + while (bufPtr == NULL || !IsBufferFull(bufPtr)) { + int code; - if (bytesInBuffer < space) { - space = bytesInBuffer; - } - memcpy(result, RemovePoint(bufPtr), (size_t) space); - bufPtr->nextRemoved += space; - copied = space; + ResetFlag(statePtr, CHANNEL_BLOCKED); + moreData: + code = GetInput(chanPtr); + bufPtr = statePtr->inQueueHead; - for (end = result + copied; result < end; result++) { - if (*result == '\r') { - *result = '\n'; + assert (bufPtr != NULL); + + if (statePtr->flags & (CHANNEL_EOF|CHANNEL_BLOCKED)) { + /* Further reads cannot do any more */ + break; } + + if (code) { + /* Read error */ + UpdateInterest(chanPtr); + Tcl_Release(chanPtr); + return -1; + } + + assert (IsBufferFull(bufPtr)); } - break; - } - case TCL_TRANSLATE_CRLF: { - char *src, *end, *dst; - int curByte; - /* - * 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; - } - return 0; - } + bytesRead = BytesLeft(bufPtr); + bytesWritten = bytesToRead; - /* - * Copy the current chunk and replace "\r\n" with "\n" (but not - * standalone "\r"!). - */ + TranslateInputEOL(statePtr, p, RemovePoint(bufPtr), + &bytesWritten, &bytesRead); + bufPtr->nextRemoved += bytesRead; + p += bytesWritten; + bytesToRead -= bytesWritten; - if (bytesInBuffer < space) { - space = bytesInBuffer; - } - memcpy(result, RemovePoint(bufPtr), (size_t) space); - bufPtr->nextRemoved += space; - copied = space; + 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. + */ - 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 (bytesToRead == 0) { + UpdateInterest(chanPtr); + break; } - if (curByte == '\r') { - SetFlag(statePtr, INPUT_SAW_CR); - } else { - *dst = (char) curByte; - dst++; + + /* + * 1) We're @EOF because we saw eof char. + */ + + if (statePtr->inEofChar + && RemovePoint(bufPtr)[0] == statePtr->inEofChar) { + UpdateInterest(chanPtr); + break; } - } - copied = dst - result; - break; - } - case TCL_TRANSLATE_AUTO: { - char *src, *end, *dst; - int curByte; - if (bytesInBuffer == 0) { - return 0; - } + /* + * 2) The buffer holds a \r while in CRLF translation, + * followed by the end of the buffer. + */ - /* - * Loop over the current buffer, converting "\r" and "\r\n" to "\n". - */ + assert(statePtr->inputTranslation == TCL_TRANSLATE_CRLF); + assert(RemovePoint(bufPtr)[0] == '\r'); + assert(BytesLeft(bufPtr) == 1); - if (bytesInBuffer < space) { - space = bytesInBuffer; - } - memcpy(result, RemovePoint(bufPtr), (size_t) space); - bufPtr->nextRemoved += space; - copied = space; + if (bufPtr->nextPtr == NULL) { + /* There's no more buffered data.... */ - 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++; + if (statePtr->flags & CHANNEL_EOF) { + /* ...and there never will be. */ + + *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; } - ResetFlag(statePtr, INPUT_SAW_CR); } - } - copied = dst - result; - break; - } - default: - Tcl_Panic("unknown eol translation mode"); - } - /* - * If an in-stream EOF character is set for this channel, check that the - * input we copied so far does not contain the EOF char. If it does, copy - * only up to and excluding that character. - */ + if (bufPtr->nextPtr) { + /* There's a next buffer. Shift orphan \r to it. */ - 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. - */ + ChannelBuffer *nextPtr = bufPtr->nextPtr; - SetFlag(statePtr, CHANNEL_EOF | CHANNEL_STICKY_EOF); - statePtr->inputEncodingFlags |= TCL_ENCODING_END; - copied = i; - break; + nextPtr->nextRemoved -= 1; + RemovePoint(nextPtr)[0] = '\r'; + bufPtr->nextRemoved++; } } - } - /* - * 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); + } - if (IsBufferEmpty(bufPtr)) { - statePtr->inQueueHead = bufPtr->nextPtr; - if (statePtr->inQueueHead == NULL) { - statePtr->inQueueTail = NULL; + if ((statePtr->flags & CHANNEL_NONBLOCKING || allowShortReads) + && statePtr->flags & CHANNEL_BLOCKED) { + break; } - RecycleBuffer(statePtr, bufPtr, 0); } - /* - * Return the number of characters copied into the result buffer. This may - * be different from the number of bytes consumed, because of EOL - * translations. - */ - - return copied; + Tcl_Release(chanPtr); + return (int)(p - dst); } /* @@ -10948,6 +10693,7 @@ 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. */ @@ -11031,13 +10777,8 @@ DumpFlags( 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'; |