/* ARGSUSED */ static void TransformWatchProc( ClientData instanceData, /* Channel to watch. */ int mask) /* Events of interest. */ { TransformChannelData *dataPtr = instanceData; Tcl_Channel downChan; /* * The caller expressed interest in events occuring for this channel. We * are forwarding the call to the underlying channel now. */ dataPtr->watchMask = mask; /* * No channel handlers any more. We will be notified automatically about * events on the channel below via a call to our 'TransformNotifyProc'. * But we have to pass the interest down now. We are allowed to add * additional 'interest' to the mask if we want to. But this * transformation has no such interest. It just passes the request down, * unchanged. */ if (dataPtr->self == NULL) { return; } downChan = Tcl_GetStackedChannel(dataPtr->self); Tcl_GetChannelType(downChan)->watchProc( Tcl_GetChannelInstanceData(downChan), mask); /* * Management of the internal timer. */ if ((dataPtr->timer != NULL) && (!(mask & TCL_READABLE) || ResultEmpty(&dataPtr->result))) { /* * A pending timer exists, but either is there no (more) interest in * the events it generates or nothing is available for reading, so * remove it. */ Tcl_DeleteTimerHandler(dataPtr->timer); dataPtr->timer = NULL; } if ((dataPtr->timer == NULL) && (mask & TCL_READABLE) && !ResultEmpty(&dataPtr->result)) { /* * There is no pending timer, but there is interest in readable events * and we actually have data waiting, so generate a timer to flush * that. */ dataPtr->timer = Tcl_CreateTimerHandler(FLUSH_DELAY, TransformChannelHandlerTimer, dataPtr); } }
static int TransformGetOptionProc( ClientData instanceData, Tcl_Interp *interp, const char *optionName, Tcl_DString *dsPtr) { TransformChannelData *dataPtr = instanceData; Tcl_Channel downChan = Tcl_GetStackedChannel(dataPtr->self); Tcl_DriverGetOptionProc *getOptionProc; getOptionProc = Tcl_ChannelGetOptionProc(Tcl_GetChannelType(downChan)); if (getOptionProc != NULL) { return getOptionProc(Tcl_GetChannelInstanceData(downChan), interp, optionName, dsPtr); } else if (optionName == NULL) { /* * Request is query for all options, this is ok. */ return TCL_OK; } /* * Request for a specific option has to fail, since we don't have any. */ return TCL_ERROR; }
static int TransformGetFileHandleProc( ClientData instanceData, /* Channel to query. */ int direction, /* Direction of interest. */ ClientData *handlePtr) /* Place to store the handle into. */ { TransformChannelData *dataPtr = instanceData; /* * Return the handle belonging to parent channel. IOW, pass the request * down and the result up. */ return Tcl_GetChannelHandle(Tcl_GetStackedChannel(dataPtr->self), direction, handlePtr); }
static int TransformSeekProc( ClientData instanceData, /* The channel to manipulate. */ long offset, /* Size of movement. */ int mode, /* How to move. */ int *errorCodePtr) /* Location of error flag. */ { TransformChannelData *dataPtr = instanceData; Tcl_Channel parent = Tcl_GetStackedChannel(dataPtr->self); const Tcl_ChannelType *parentType = Tcl_GetChannelType(parent); Tcl_DriverSeekProc *parentSeekProc = Tcl_ChannelSeekProc(parentType); if ((offset == 0) && (mode == SEEK_CUR)) { /* * This is no seek but a request to tell the caller the current * location. Simply pass the request down. */ return parentSeekProc(Tcl_GetChannelInstanceData(parent), offset, mode, errorCodePtr); } /* * It is a real request to change the position. Flush all data waiting for * output and discard everything in the input buffers. Then pass the * request down, unchanged. */ PreserveData(dataPtr); if (dataPtr->mode & TCL_WRITABLE) { ExecuteCallback(dataPtr, NULL, A_FLUSH_WRITE, NULL, 0, TRANSMIT_DOWN, P_NO_PRESERVE); } if (dataPtr->mode & TCL_READABLE) { ExecuteCallback(dataPtr, NULL, A_CLEAR_READ, NULL, 0, TRANSMIT_DONT, P_NO_PRESERVE); ResultClear(&dataPtr->result); dataPtr->readIsFlushed = 0; dataPtr->eofPending = 0; } ReleaseData(dataPtr); return parentSeekProc(Tcl_GetChannelInstanceData(parent), offset, mode, errorCodePtr); }
static int TransformSetOptionProc( ClientData instanceData, Tcl_Interp *interp, const char *optionName, const char *value) { TransformChannelData *dataPtr = instanceData; Tcl_Channel downChan = Tcl_GetStackedChannel(dataPtr->self); Tcl_DriverSetOptionProc *setOptionProc; setOptionProc = Tcl_ChannelSetOptionProc(Tcl_GetChannelType(downChan)); if (setOptionProc == NULL) { return TCL_ERROR; } return setOptionProc(Tcl_GetChannelInstanceData(downChan), interp, optionName, value); }
static Tcl_WideInt TransformWideSeekProc( ClientData instanceData, /* The channel to manipulate. */ Tcl_WideInt offset, /* Size of movement. */ int mode, /* How to move. */ int *errorCodePtr) /* Location of error flag. */ { TransformChannelData *dataPtr = instanceData; Tcl_Channel parent = Tcl_GetStackedChannel(dataPtr->self); const Tcl_ChannelType *parentType = Tcl_GetChannelType(parent); Tcl_DriverSeekProc *parentSeekProc = Tcl_ChannelSeekProc(parentType); Tcl_DriverWideSeekProc *parentWideSeekProc = Tcl_ChannelWideSeekProc(parentType); ClientData parentData = Tcl_GetChannelInstanceData(parent); if ((offset == Tcl_LongAsWide(0)) && (mode == SEEK_CUR)) { /* * This is no seek but a request to tell the caller the current * location. Simply pass the request down. */ if (parentWideSeekProc != NULL) { return parentWideSeekProc(parentData, offset, mode, errorCodePtr); } return Tcl_LongAsWide(parentSeekProc(parentData, 0, mode, errorCodePtr)); } /* * It is a real request to change the position. Flush all data waiting for * output and discard everything in the input buffers. Then pass the * request down, unchanged. */ PreserveData(dataPtr); if (dataPtr->mode & TCL_WRITABLE) { ExecuteCallback(dataPtr, NULL, A_FLUSH_WRITE, NULL, 0, TRANSMIT_DOWN, P_NO_PRESERVE); } if (dataPtr->mode & TCL_READABLE) { ExecuteCallback(dataPtr, NULL, A_CLEAR_READ, NULL, 0, TRANSMIT_DONT, P_NO_PRESERVE); ResultClear(&dataPtr->result); dataPtr->readIsFlushed = 0; dataPtr->eofPending = 0; } ReleaseData(dataPtr); /* * If we have a wide seek capability, we should stick with that. */ if (parentWideSeekProc != NULL) { return parentWideSeekProc(parentData, offset, mode, errorCodePtr); } /* * We're transferring to narrow seeks at this point; this is a bit complex * because we have to check whether the seek is possible first (i.e. * whether we are losing information in truncating the bits of the * offset). Luckily, there's a defined error for what happens when trying * to go out of the representable range. */ if (offset<Tcl_LongAsWide(LONG_MIN) || offset>Tcl_LongAsWide(LONG_MAX)) { *errorCodePtr = EOVERFLOW; return Tcl_LongAsWide(-1); } return Tcl_LongAsWide(parentSeekProc(parentData, Tcl_WideAsLong(offset), mode, errorCodePtr)); }
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 ExecuteCallback( TransformChannelData *dataPtr, /* Transformation with the callback. */ Tcl_Interp *interp, /* Current interpreter, possibly NULL. */ unsigned char *op, /* Operation invoking the callback. */ unsigned char *buf, /* Buffer to give to the script. */ int bufLen, /* And its length. */ int transmit, /* Flag, determines whether the result of the * callback is sent to the underlying channel * or not. */ int preserve) /* Flag. If true the procedure will preserve * the result state of all accessed * interpreters. */ { Tcl_Obj *resObj; /* See below, switch (transmit). */ int resLen; unsigned char *resBuf; Tcl_InterpState state = NULL; int res = TCL_OK; Tcl_Obj *command = TclListObjCopy(NULL, dataPtr->command); Tcl_Interp *eval = dataPtr->interp; Tcl_Preserve(eval); /* * Step 1, create the complete command to execute. Do this by appending * operation and buffer to operate upon to a copy of the callback * definition. We *cannot* create a list containing 3 objects and then use * 'Tcl_EvalObjv', because the command may contain additional prefixed * arguments. Feather's curried commands would come in handy here. */ if (preserve == P_PRESERVE) { state = Tcl_SaveInterpState(eval, res); } Tcl_IncrRefCount(command); Tcl_ListObjAppendElement(NULL, command, Tcl_NewStringObj((char *) op, -1)); /* * Use a byte-array to prevent the misinterpretation of binary data coming * through as UTF while at the tcl level. */ Tcl_ListObjAppendElement(NULL, command, Tcl_NewByteArrayObj(buf, bufLen)); /* * Step 2, execute the command at the global level of the interpreter used * to create the transformation. Destroy the command afterward. If an * error occured and the current interpreter is defined and not equal to * the interpreter for the callback, then copy the error message into * current interpreter. Don't copy if in preservation mode. */ res = Tcl_EvalObjEx(eval, command, TCL_EVAL_GLOBAL); Tcl_DecrRefCount(command); command = NULL; if ((res != TCL_OK) && (interp != NULL) && (eval != interp) && (preserve == P_NO_PRESERVE)) { Tcl_SetObjResult(interp, Tcl_GetObjResult(eval)); Tcl_Release(eval); return res; } /* * Step 3, transmit a possible conversion result to the underlying * channel, or ourselves. */ switch (transmit) { case TRANSMIT_DONT: /* nothing to do */ break; case TRANSMIT_DOWN: if (dataPtr->self == NULL) { break; } resObj = Tcl_GetObjResult(eval); resBuf = Tcl_GetByteArrayFromObj(resObj, &resLen); Tcl_WriteRaw(Tcl_GetStackedChannel(dataPtr->self), (char *) resBuf, resLen); break; case TRANSMIT_SELF: if (dataPtr->self == NULL) { break; } resObj = Tcl_GetObjResult(eval); resBuf = Tcl_GetByteArrayFromObj(resObj, &resLen); Tcl_WriteRaw(dataPtr->self, (char *) resBuf, resLen); break; case TRANSMIT_IBUF: resObj = Tcl_GetObjResult(eval); resBuf = Tcl_GetByteArrayFromObj(resObj, &resLen); ResultAdd(&dataPtr->result, resBuf, resLen); break; case TRANSMIT_NUM: /* * Interpret result as integer number. */ resObj = Tcl_GetObjResult(eval); TclGetIntFromObj(eval, resObj, &dataPtr->maxRead); break; } Tcl_ResetResult(eval); if (preserve == P_PRESERVE) { (void) Tcl_RestoreInterpState(eval, state); } Tcl_Release(eval); return res; }
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; }