static inline void
ResultAdd(
ResultBuffer *r, /* The buffer to extend. */
unsigned char *buf, /* The buffer to read from. */
size_t toWrite) /* The number of bytes in 'buf'. */
{
if (r->used + toWrite > r->allocated) {
/*
* Extension of the internal buffer is required.
*/
if (r->allocated == 0) {
r->allocated = toWrite + INCREMENT;
r->buf = UCHARP(ckalloc(r->allocated));
} else {
r->allocated += toWrite + INCREMENT;
r->buf = UCHARP(ckrealloc((char *) r->buf, r->allocated));
}
}
/*
* Now we may copy the data.
*/
memcpy(r->buf + r->used, buf, toWrite);
r->used += toWrite;
}
static int
TransformOutputProc(
ClientData instanceData,
const char *buf,
int toWrite,
int *errorCodePtr)
{
TransformChannelData *dataPtr = instanceData;
/*
* Should assert(dataPtr->mode & TCL_WRITABLE);
*/
if (toWrite == 0) {
/*
* Catch a no-op.
*/
return 0;
}
PreserveData(dataPtr);
if (ExecuteCallback(dataPtr, NULL, A_WRITE, UCHARP(buf), toWrite,
TRANSMIT_DOWN, P_NO_PRESERVE) != TCL_OK) {
*errorCodePtr = EINVAL;
toWrite = -1;
}
ReleaseData(dataPtr);
return toWrite;
}
static int
TransformInputProc(
ClientData instanceData,
char *buf,
int toRead,
int *errorCodePtr)
{
TransformChannelData *dataPtr = instanceData;
int gotBytes, read, copied;
Tcl_Channel downChan;
/*
* Should assert(dataPtr->mode & TCL_READABLE);
*/
if (toRead == 0 || dataPtr->self == NULL) {
/*
* Catch a no-op. TODO: Is this a panic()?
*/
return 0;
}
gotBytes = 0;
downChan = Tcl_GetStackedChannel(dataPtr->self);
PreserveData(dataPtr);
while (toRead > 0) {
/*
* Loop until the request is satisfied (or no data is available from
* below, possibly EOF).
*/
copied = ResultCopy(&dataPtr->result, UCHARP(buf), toRead);
toRead -= copied;
buf += copied;
gotBytes += copied;
if (toRead == 0) {
/*
* The request was completely satisfied from our buffers. We can
* break out of the loop and return to the caller.
*/
break;
}
/*
* Length (dataPtr->result) == 0, toRead > 0 here. Use the incoming
* 'buf'! as target to store the intermediary information read from
* the underlying channel.
*
* Ask the tcl level how much data it allows us to read from the
* underlying channel. This feature allows the transform to signal EOF
* upstream although there is none downstream. Useful to control an
* unbounded 'fcopy', either through counting bytes, or by pattern
* matching.
*/
ExecuteCallback(dataPtr, NULL, A_QUERY_MAXREAD, NULL, 0,
TRANSMIT_NUM /* -> maxRead */, P_PRESERVE);
if (dataPtr->maxRead >= 0) {
if (dataPtr->maxRead < toRead) {
toRead = dataPtr->maxRead;
}
} /* else: 'maxRead < 0' == Accept the current value of toRead. */
if (toRead <= 0) {
break;
}
if (dataPtr->eofPending) {
/*
* Already saw EOF from downChan; don't ask again.
* NOTE: Could move this up to avoid the last maxRead
* execution. Believe this would still be correct behavior,
* but the test suite tests the whole command callback
* sequence, so leave it unchanged for now.
*/
break;
}
/*
* Get bytes from the underlying channel.
*/
read = Tcl_ReadRaw(downChan, buf, toRead);
if (read < 0) {
if (Tcl_InputBlocked(downChan) && (gotBytes > 0)) {
/*
* Zero bytes available from downChan because blocked.
* But nonzero bytes already copied, so total is a
* valid blocked short read. Return to caller.
*/
break;
}
/*
* Either downChan is not blocked (there's a real error).
* or it is and there are no bytes copied yet. In either
* case we want to pass the "error" along to the caller,
* either to report an error, or to signal to the caller
* that zero bytes are available because blocked.
*/
*errorCodePtr = Tcl_GetErrno();
gotBytes = -1;
break;
} else if (read == 0) {
/*
* Zero returned from Tcl_ReadRaw() always indicates EOF
* on the down channel.
*/
dataPtr->eofPending = 1;
dataPtr->readIsFlushed = 1;
ExecuteCallback(dataPtr, NULL, A_FLUSH_READ, NULL, 0,
TRANSMIT_IBUF, P_PRESERVE);
if (ResultEmpty(&dataPtr->result)) {
/*
* We had nothing to flush.
*/
break;
}
continue; /* at: while (toRead > 0) */
} /* read == 0 */
/*
* Transform the read chunk and add the result to our read buffer
* (dataPtr->result).
*/
if (ExecuteCallback(dataPtr, NULL, A_READ, UCHARP(buf), read,
TRANSMIT_IBUF, P_PRESERVE) != TCL_OK) {
*errorCodePtr = EINVAL;
gotBytes = -1;
break;
}
} /* while toRead > 0 */
if (gotBytes == 0) {
dataPtr->eofPending = 0;
}
ReleaseData(dataPtr);
return gotBytes;
}
static int
TransformInputProc(
ClientData instanceData,
char *buf,
int toRead,
int *errorCodePtr)
{
TransformChannelData *dataPtr = instanceData;
int gotBytes, read, copied;
Tcl_Channel downChan;
/*
* Should assert(dataPtr->mode & TCL_READABLE);
*/
if (toRead == 0) {
/*
* Catch a no-op.
*/
return 0;
}
gotBytes = 0;
downChan = Tcl_GetStackedChannel(dataPtr->self);
while (toRead > 0) {
/*
* Loop until the request is satisfied (or no data is available from
* below, possibly EOF).
*/
copied = ResultCopy(&dataPtr->result, UCHARP(buf), toRead);
toRead -= copied;
buf += copied;
gotBytes += copied;
if (toRead == 0) {
/*
* The request was completely satisfied from our buffers. We can
* break out of the loop and return to the caller.
*/
return gotBytes;
}
/*
* Length (dataPtr->result) == 0, toRead > 0 here. Use the incoming
* 'buf'! as target to store the intermediary information read from
* the underlying channel.
*
* Ask the tcl level how much data it allows us to read from the
* underlying channel. This feature allows the transform to signal EOF
* upstream although there is none downstream. Useful to control an
* unbounded 'fcopy', either through counting bytes, or by pattern
* matching.
*/
ExecuteCallback(dataPtr, NULL, A_QUERY_MAXREAD, NULL, 0,
TRANSMIT_NUM /* -> maxRead */, P_PRESERVE);
if (dataPtr->maxRead >= 0) {
if (dataPtr->maxRead < toRead) {
toRead = dataPtr->maxRead;
}
} /* else: 'maxRead < 0' == Accept the current value of toRead. */
if (toRead <= 0) {
return gotBytes;
}
/*
* Get bytes from the underlying channel.
*/
read = Tcl_ReadRaw(downChan, buf, toRead);
if (read < 0) {
/*
* Report errors to caller. EAGAIN is a special situation. If we
* had some data before we report that instead of the request to
* re-try.
*/
if ((Tcl_GetErrno() == EAGAIN) && (gotBytes > 0)) {
return gotBytes;
}
*errorCodePtr = Tcl_GetErrno();
return -1;
} else if (read == 0) {
/*
* Check wether we hit on EOF in the underlying channel or not. If
* not differentiate between blocking and non-blocking modes. In
* non-blocking mode we ran temporarily out of data. Signal this
* to the caller via EWOULDBLOCK and error return (-1). In the
* other cases we simply return what we got and let the caller
* wait for more. On the other hand, if we got an EOF we have to
* convert and flush all waiting partial data.
*/
if (!Tcl_Eof(downChan)) {
if ((gotBytes == 0) && (dataPtr->flags & CHANNEL_ASYNC)) {
*errorCodePtr = EWOULDBLOCK;
return -1;
}
return gotBytes;
}
if (dataPtr->readIsFlushed) {
/*
* Already flushed, nothing to do anymore.
*/
return gotBytes;
}
dataPtr->readIsFlushed = 1;
ExecuteCallback(dataPtr, NULL, A_FLUSH_READ, NULL, 0,
TRANSMIT_IBUF, P_PRESERVE);
if (ResultEmpty(&dataPtr->result)) {
/*
* We had nothing to flush.
*/
return gotBytes;
}
continue; /* at: while (toRead > 0) */
} /* read == 0 */
/*
* Transform the read chunk and add the result to our read buffer
* (dataPtr->result).
*/
if (ExecuteCallback(dataPtr, NULL, A_READ, UCHARP(buf), read,
TRANSMIT_IBUF, P_PRESERVE) != TCL_OK) {
*errorCodePtr = EINVAL;
return -1;
}
} /* while toRead > 0 */
return gotBytes;
}
