/*
* generic/dpIdentity.c --
*
* This file contains the implementation of the identity filter channels.
* These are channels that are created by evaluating "dp_connect identity".
*
*/
#include <string.h>
#include <errno.h>
#include <tcl.h>
#include <generic/dpInt.h>
/*
* Prototypes for functions referenced only in this file.
*/
static int CloseIdChannel _ANSI_ARGS_((ClientData instanceData,
Tcl_Interp *interp));
static int InputIdChannel _ANSI_ARGS_((ClientData instanceData,
char *buf, int bufsize,
int *errorCodePtr));
static int OutputIdChannel _ANSI_ARGS_((ClientData instanceData,
char *buf, int toWrite,
int *errorCodePtr));
static int SOPIdChannel _ANSI_ARGS_((ClientData instanceData,
Tcl_Interp *interp,
char *optionName,
char *optionValue));
#ifdef _TCL76
static int GOPIdChannel _ANSI_ARGS_((ClientData instanceData,
char *optionName,
Tcl_DString *dsPtr));
#else
static int GOPIdChannel _ANSI_ARGS_((ClientData instanceData,
Tcl_Interp *interp,
char *optionName,
Tcl_DString *dsPtr));
#endif
#ifndef _TCL76
static int GFPIdChannel _ANSI_ARGS_((ClientData instanceData,
int direction,
FileHandle *handlePtr));
#else
static Tcl_File GFPIdChannel _ANSI_ARGS_((ClientData instanceData,
int direction));
#endif
static int CRPIdChannel _ANSI_ARGS_((ClientData instanceData,
int mask));
static void WCPIdChannel _ANSI_ARGS_((ClientData instanceData,
int mask));
/*
* This structure stores the names of the functions that Tcl calls when certain
* actions have to be performed on an identity channel. To understand this entry,
* please refer to the documentation of the Tcl_CreateChannel and its associated
* functions in the Tcl 7.6 documentation.
*
* An identity channel will always be non-blocking.
* Seek on an identity channel is not allowed.
*/
Tcl_ChannelType idChannelType = {
"idfilter",
NULL, /* blockModeProc */
CloseIdChannel, /* closeProc */
InputIdChannel, /* inputProc */
OutputIdChannel, /* outputProc */
NULL, /* seekProc */
SOPIdChannel, /* setOptionProc */
GOPIdChannel, /* getOptionProc */
WCPIdChannel, /* watchChannelProc */
#ifdef _TCL76
CRPIdChannel, /* channelReadyProc */
#endif
GFPIdChannel /* getFileProc */
};
/*
* Structure that stores the data needed to manage an identity filter.
*/
typedef struct {
/* Pointer to the subordinated channel. */
Tcl_Channel channelPtr;
/* If peek = 0 consume input, otherwise not. */
int peek;
}
IdentityInfo;
/*
*-----------------------------------------------------------------------------
*
* DpCreateIdChannel --
*
* Creates an identity filter channel.
*
* Results:
*
* Returns a channel data structure. If an error happens, NULL
* is returned.
*
* Side effects:
*
* Alocates memory for the instance data that is associated
* with the channel.
*
* ----------------------------------------------------------------------------
*/
Tcl_Channel
DpCreateIdChannel (interp, argc, argv)
Tcl_Interp *interp; /* (in) Pointer to tcl interpreter. */
int argc; /* (in) Number of arguments. */
char **argv; /* (in) Argument strings. */
{
static int openedChannels = 0;
int i;
IdentityInfo *instanceData;
Tcl_Channel newChannel;
char chanName [20];
instanceData = (IdentityInfo *)ckalloc(sizeof(IdentityInfo));
if(instanceData == NULL) {
Tcl_AppendResult(interp, "unable to allocate memory for identity ",
"filter channel", NULL);
return NULL;
}
instanceData->channelPtr = NULL;
for (i = 0; i < argc; i += 2) {
int v = i+1;
size_t len = strlen(argv[i]);
if (strncmp(argv[i], "-channel", len)==0) {
if (v == argc) {
goto error2;
}
instanceData->channelPtr = Tcl_GetChannel(interp, argv[v], NULL);
if(instanceData->channelPtr == NULL) {
goto error1;
}
} else {
Tcl_AppendResult(interp, "unknown option \"",
argv[i], "\", must be -channel", NULL);
goto error1;
}
}
if(instanceData->channelPtr == NULL) {
Tcl_AppendResult(interp, "-channel must be defined for an identity ",
"channel", NULL);
goto error1;
}
/* No peek by default. */
instanceData->peek = 0;
/* Identity filters are both readable and writable. */
sprintf(chanName, "idfilter%d", openedChannels++);
newChannel = Tcl_CreateChannel(&idChannelType, chanName,
(ClientData)instanceData, TCL_READABLE | TCL_WRITABLE);
if(newChannel == NULL) {
Tcl_AppendResult(interp, "tcl unable to create identity channel", NULL);
goto error1;
}
Tcl_RegisterChannel(interp, newChannel);
return newChannel;
error2:
Tcl_AppendResult(interp, "option value missing for -channel", NULL);
/* continues with error1 */
error1:
ckfree((char *)instanceData);
return NULL;
}
/*
*-----------------------------------------------------------------------------
*
* CloseIdChannel --
*
* Closes the given identity filter channel.
*
* Results:
*
* If everything goes well, returns 0. If any error happens,
* it returns a POSIX error code.
*
* Side effects:
*
* It frees the instance data associated with the channel.
*
* ----------------------------------------------------------------------------
*/
static int
CloseIdChannel (instanceData, interp)
ClientData instanceData; /* (in) Pointer to IdentityInfo struct. */
Tcl_Interp *interp; /* Pointer to the tcl interpreter. */
{
ckfree((char *)instanceData);
return 0;
}
/*
*-----------------------------------------------------------------------------
*
* InputIdChannel --
*
* Reads min(requested data, available data) from the subordinated channel.
*
* Results:
*
* Number of bytes of data read from the subordinated filter. If an error
* happened, it returns -1.
*
* Side effects:
*
* 1. Calls the read procedure of the subordinated channel.
* 2. Stores a POSIX code at errorBuffer if an error occurs.
*
* ----------------------------------------------------------------------------
*/
static int
InputIdChannel (instanceData, buf, bufsize, errorCodePtr)
ClientData instanceData; /* (in) Pointer to IdentityInfo struct. */
char *buf; /* (in/out) Buffer to fill. */
int bufsize; /* (in) Size of buffer. */
int *errorCodePtr; /* (out) POSIX error code (if any). */
{
int tmp;
Tcl_Channel channelPtr = ((IdentityInfo *)instanceData)->channelPtr;
tmp = Tcl_Read(channelPtr, buf, bufsize);
if(tmp == -1) {
*errorCodePtr = Tcl_GetErrno();
}
return tmp;
}
/*
*-----------------------------------------------------------------------------
*
* OutputIdChannel --
*
* Writes the data to the subordinated channel.
*
* Results:
*
* Number of writes written, or -1 if an error is signalled from the
* subordinated filter.
*
* Side effects:
*
* 1. Calls the write procedure of the subordinated channel.
* 2. Stores a POSIX code at errorBuffer if an error occurs.
*
* ----------------------------------------------------------------------------
*/
static int
OutputIdChannel (instanceData, buf, toWrite, errorCodePtr)
ClientData instanceData; /* channel to send the message to */
char *buf; /* output buffer */
int toWrite; /* number of characters to write */
int *errorCodePtr; /* place to store the POSIX error code */
{
int tmp;
Tcl_Channel channelPtr = ((IdentityInfo *)instanceData)->channelPtr;
tmp = Tcl_Write(channelPtr, buf, toWrite);
if(tmp == -1) {
*errorCodePtr = Tcl_GetErrno();
}
return tmp;
}
/*
*-----------------------------------------------------------------------------
*
* GFPIdChannel --
*
* "Get file" function for identity channels. Since there are no files
* associated with filters, it always returns NULL.
*
* Results:
*
* Always NULL.
*
* Side effects:
*
* None.
*
* ----------------------------------------------------------------------------
*/
/* ARGSUSED */
#ifndef _TCL76
static int
GFPIdChannel (instanceData, direction, handlePtr)
ClientData instanceData;
int direction;
FileHandle *handlePtr;
{
*handlePtr = NULL;
return TCL_OK;
}
#else
static Tcl_File
GFPIdChannel (instanceData, direction)
ClientData instanceData;
int direction;
{
return NULL;
}
#endif
/*
*-----------------------------------------------------------------------------
*
* SOPIdChannel --
*
* "Set option" procedure for identity channels.
*
* Results:
*
* Standard Tcl result.
*
* Side effects:
*
* Sets the value of the specified option.
*
* ----------------------------------------------------------------------------
*/
static int
SOPIdChannel (instanceData, interp, optionName, optionValue)
ClientData instanceData; /* (in) Pointer to IdentityInfo struct. */
Tcl_Interp *interp; /* (in) Pointer to tcl interpreter. */
char *optionName;
char *optionValue;
{
int option;
int value;
IdentityInfo data;
memcpy((void *)&data, (void *)instanceData, sizeof(IdentityInfo));
/*
* Set the option specified by optionName
*/
if (optionName[0] == '-') {
option = DpTranslateOption(optionName+1);
} else {
option = -1;
}
switch(option) {
case DP_PEEK:
if (Tcl_GetBoolean(interp, optionValue, &value) != TCL_OK) {
return TCL_ERROR;
}
if (value == 0) {
data.peek = 0;
if (Tcl_SetChannelOption(interp, data.channelPtr,
"-peek", "no") == TCL_ERROR) {
Tcl_AppendResult(interp, ": subordinated channel error in ",
Tcl_GetChannelName(data.channelPtr), NULL);
return TCL_ERROR;
}
} else {
data.peek = 1;
if (Tcl_SetChannelOption(interp, data.channelPtr,
"-peek", "yes") == TCL_ERROR) {
Tcl_AppendResult(interp, ": subordinated channel error in ",
Tcl_GetChannelName(data.channelPtr), NULL);
return TCL_ERROR;
}
}
break;
case DP_CHANNEL:
Tcl_AppendResult(interp, "can't set channel after identity channel ",
"is opened", NULL);
return TCL_ERROR;
default:
Tcl_AppendResult (interp, "illegal option \"", optionName, "\" -- ",
"must be peek, or a standard fconfigure option", NULL);
return TCL_ERROR;
}
return TCL_OK;
}
/*
*--------------------------------------------------------------------------
*
* GOPIdChannel --
*
* "Get option" function for identity filters.
*
* Results:
*
* Standard Tcl result.
*
* Side effects:
*
* Returns the value of a non-standard option. If no option is specified,
* a list of all options, together with their values, is returned.
*
* -------------------------------------------------------------------------
*/
static int
GOPIdChannel (instanceData,
#ifdef _TCL80
interp,
#endif
optionName, dsPtr)
ClientData instanceData;
#ifdef _TCL80
Tcl_Interp *interp;
#endif
char *optionName;
Tcl_DString *dsPtr; /* (out) String to store the result in. */
{
int option;
int size;
/*
* If optionName is NULL, then store an alternating list of
* all supported options and their current values in dsPtr.
*/
#ifdef _TCL80
#define IGO(a, b, c) GOPIdChannel(a, interp, b, c)
#else
#define IGO(a, b, c) GOPIdChannel(a, b, c)
#endif
if (optionName == NULL) {
Tcl_DStringAppend (dsPtr, " -channel ", -1);
IGO (instanceData, "-channel", dsPtr);
Tcl_DStringAppend (dsPtr, " -peek ", -1);
IGO (instanceData, "-peek", dsPtr);
return TCL_OK;
}
#undef IGO
/*
* Retrieve the value of the option specified by optionName
*/
if (optionName[0] == '-') {
option = DpTranslateOption(optionName+1);
} else {
option = -1;
}
switch (option) {
case DP_PEEK:
if (((IdentityInfo *)instanceData)->peek) {
Tcl_DStringAppend (dsPtr, "1", -1);
} else {
Tcl_DStringAppend (dsPtr, "0", -1);
}
break;
case DP_CHANNEL:
Tcl_DStringAppend (dsPtr,
Tcl_GetChannelName(((IdentityInfo *)instanceData)->channelPtr), -1);
break;
default:
#ifndef _TCL76
Tcl_AppendResult(interp,
"bad option \"", optionName,"\": must be -blocking,",
" -buffering, -buffersize, -eofchar, -translation,",
" or a channel type specific option", NULL);
#else
{
char errStr[128];
sprintf(errStr, "bad option \"%s\": must be -blocking,"
"-buffering, -buffersize, -eofchar, -translation,"
" or a channel type specific option", optionName);
Tcl_DStringAppend(dsPtr, errStr, -1);
}
#endif
Tcl_SetErrno (EINVAL);
return TCL_ERROR;
}
return TCL_OK;
}
/*
*-----------------------------------------------------------------------------
*
* WCPIdChannel --
*
* This is the "watch channel" procedure for identity filters. It is
* assumed that no events are generated internally in the filter channel,
* so the procedure only calls the corresponding procedure of the
* subordinated channel.
*
* Results:
*
* None.
*
* Side effects:
*
* Calls the "watch channel" procedure of the subordinated channel.
*
* ----------------------------------------------------------------------------
*/
static void
WCPIdChannel (instanceData, mask)
ClientData instanceData; /* (in) Pointer to PlugFInfo struct. */
int mask; /* (in) ORed combination of TCL_READABLE,
* TCL_WRITABLE and TCL_EXCEPTION. It designates
* the event categories that have to be watched.
*/
{
Tcl_Channel channelPtr = ((IdentityInfo *)instanceData)->channelPtr;
#ifdef _TCL76
(Tcl_GetChannelType(channelPtr)->watchChannelProc)
(Tcl_GetChannelInstanceData(channelPtr), mask);
#endif
return;
}
/*
*-----------------------------------------------------------------------------
*
* CRPIdChannel --
*
* This is the "channel ready" procedure for identity filters. It is
* assumed that no events are generated internally in the filter channel,
* so the procedure only calls the corresponding procedure of the
* subordinated channel.
*
* Results:
*
* The value returned by the "channel ready" procedure of the subordinated
* channel.
*
* Side effects:
*
* Calls the "channel ready" procedure of the subordinated channel.
*
* ----------------------------------------------------------------------------
*/
static int
CRPIdChannel (instanceData, mask)
ClientData instanceData; /* (in) Pointer to IdentityInfo struct. */
int mask; /* (in) ORed combination of TCL_READABLE,
* TCL_WRITABLE and TCL_EXCEPTION. It designates
* the event categories whose occurence has to
* be signalled.
*/
{
Tcl_Channel channelPtr = ((IdentityInfo *)instanceData)->channelPtr;
#ifdef _TCL76
return (Tcl_GetChannelType(channelPtr)->channelReadyProc)
(Tcl_GetChannelInstanceData(channelPtr), mask);
#else
return TCL_OK;
#endif
}