freebsd-dev/contrib/tcl/unix/tclUnixPipe.c
1997-07-25 19:27:55 +00:00

1150 lines
29 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* tclUnixPipe.c --
*
* This file implements the UNIX-specific exec pipeline functions,
* the "pipe" channel driver, and the "pid" Tcl command.
*
* Copyright (c) 1991-1994 The Regents of the University of California.
* Copyright (c) 1994-1997 Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and redistribution
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
* SCCS: @(#) tclUnixPipe.c 1.36 97/05/14 13:24:24
*/
#include "tclInt.h"
#include "tclPort.h"
/*
* The following macros convert between TclFile's and fd's. The conversion
* simple involves shifting fd's up by one to ensure that no valid fd is ever
* the same as NULL.
*/
#define MakeFile(fd) ((TclFile)((fd)+1))
#define GetFd(file) (((int)file)-1)
/*
* This structure describes per-instance state of a pipe based channel.
*/
typedef struct PipeState {
Tcl_Channel channel;/* Channel associated with this file. */
TclFile inFile; /* Output from pipe. */
TclFile outFile; /* Input to pipe. */
TclFile errorFile; /* Error output from pipe. */
int numPids; /* How many processes are attached to this pipe? */
Tcl_Pid *pidPtr; /* The process IDs themselves. Allocated by
* the creator of the pipe. */
int isNonBlocking; /* Nonzero when the pipe is in nonblocking mode.
* Used to decide whether to wait for the children
* at close time. */
} PipeState;
/*
* Declarations for local procedures defined in this file:
*/
static int PipeBlockModeProc _ANSI_ARGS_((ClientData instanceData,
int mode));
static int PipeCloseProc _ANSI_ARGS_((ClientData instanceData,
Tcl_Interp *interp));
static int PipeGetHandleProc _ANSI_ARGS_((ClientData instanceData,
int direction, ClientData *handlePtr));
static int PipeInputProc _ANSI_ARGS_((ClientData instanceData,
char *buf, int toRead, int *errorCode));
static int PipeOutputProc _ANSI_ARGS_((
ClientData instanceData, char *buf, int toWrite,
int *errorCode));
static void PipeWatchProc _ANSI_ARGS_((ClientData instanceData, int mask));
static void RestoreSignals _ANSI_ARGS_((void));
static int SetupStdFile _ANSI_ARGS_((TclFile file, int type));
/*
* This structure describes the channel type structure for command pipe
* based IO:
*/
static Tcl_ChannelType pipeChannelType = {
"pipe", /* Type name. */
PipeBlockModeProc, /* Set blocking/nonblocking mode.*/
PipeCloseProc, /* Close proc. */
PipeInputProc, /* Input proc. */
PipeOutputProc, /* Output proc. */
NULL, /* Seek proc. */
NULL, /* Set option proc. */
NULL, /* Get option proc. */
PipeWatchProc, /* Initialize notifier. */
PipeGetHandleProc, /* Get OS handles out of channel. */
};
/*
*----------------------------------------------------------------------
*
* TclpMakeFile --
*
* Make a TclFile from a channel.
*
* Results:
* Returns a new TclFile or NULL on failure.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
TclFile
TclpMakeFile(channel, direction)
Tcl_Channel channel; /* Channel to get file from. */
int direction; /* Either TCL_READABLE or TCL_WRITABLE. */
{
int fd;
if (Tcl_GetChannelHandle(channel, direction, (ClientData *) &fd)
== TCL_OK) {
return MakeFile(fd);
} else {
return (TclFile) NULL;
}
}
/*
*----------------------------------------------------------------------
*
* TclpOpenFile --
*
* Open a file for use in a pipeline.
*
* Results:
* Returns a new TclFile handle or NULL on failure.
*
* Side effects:
* May cause a file to be created on the file system.
*
*----------------------------------------------------------------------
*/
TclFile
TclpOpenFile(fname, mode)
char *fname; /* The name of the file to open. */
int mode; /* In what mode to open the file? */
{
int fd;
fd = open(fname, mode, 0666);
if (fd != -1) {
fcntl(fd, F_SETFD, FD_CLOEXEC);
/*
* If the file is being opened for writing, seek to the end
* so we can append to any data already in the file.
*/
if (mode & O_WRONLY) {
lseek(fd, 0, SEEK_END);
}
/*
* Increment the fd so it can't be 0, which would conflict with
* the NULL return for errors.
*/
return MakeFile(fd);
}
return NULL;
}
/*
*----------------------------------------------------------------------
*
* TclpCreateTempFile --
*
* This function creates a temporary file initialized with an
* optional string, and returns a file handle with the file pointer
* at the beginning of the file.
*
* Results:
* A handle to a file.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
TclFile
TclpCreateTempFile(contents, namePtr)
char *contents; /* String to write into temp file, or NULL. */
Tcl_DString *namePtr; /* If non-NULL, pointer to initialized
* DString that is filled with the name of
* the temp file that was created. */
{
char fileName[L_tmpnam];
TclFile file;
size_t length = (contents == NULL) ? 0 : strlen(contents);
tmpnam(fileName);
file = TclpOpenFile(fileName, O_RDWR|O_CREAT|O_TRUNC);
unlink(fileName);
if ((file != NULL) && (length > 0)) {
int fd = GetFd(file);
while (1) {
if (write(fd, contents, length) != -1) {
break;
} else if (errno != EINTR) {
close(fd);
return NULL;
}
}
lseek(fd, 0, SEEK_SET);
}
if (namePtr != NULL) {
Tcl_DStringAppend(namePtr, fileName, -1);
}
return file;
}
/*
*----------------------------------------------------------------------
*
* TclpCreatePipe --
*
* Creates a pipe - simply calls the pipe() function.
*
* Results:
* Returns 1 on success, 0 on failure.
*
* Side effects:
* Creates a pipe.
*
*----------------------------------------------------------------------
*/
int
TclpCreatePipe(readPipe, writePipe)
TclFile *readPipe; /* Location to store file handle for
* read side of pipe. */
TclFile *writePipe; /* Location to store file handle for
* write side of pipe. */
{
int pipeIds[2];
if (pipe(pipeIds) != 0) {
return 0;
}
fcntl(pipeIds[0], F_SETFD, FD_CLOEXEC);
fcntl(pipeIds[1], F_SETFD, FD_CLOEXEC);
*readPipe = MakeFile(pipeIds[0]);
*writePipe = MakeFile(pipeIds[1]);
return 1;
}
/*
*----------------------------------------------------------------------
*
* TclpCloseFile --
*
* Implements a mechanism to close a UNIX file.
*
* Results:
* Returns 0 on success, or -1 on error, setting errno.
*
* Side effects:
* The file is closed.
*
*----------------------------------------------------------------------
*/
int
TclpCloseFile(file)
TclFile file; /* The file to close. */
{
int fd = GetFd(file);
/*
* Refuse to close the fds for stdin, stdout and stderr.
*/
if ((fd == 0) || (fd == 1) || (fd == 2)) {
return 0;
}
Tcl_DeleteFileHandler(fd);
return close(fd);
}
/*
*----------------------------------------------------------------------
*
* TclpCreateProcess --
*
* Create a child process that has the specified files as its
* standard input, output, and error. The child process runs
* asynchronously and runs with the same environment variables
* as the creating process.
*
* The path is searched to find the specified executable.
*
* Results:
* The return value is TCL_ERROR and an error message is left in
* interp->result if there was a problem creating the child
* process. Otherwise, the return value is TCL_OK and *pidPtr is
* filled with the process id of the child process.
*
* Side effects:
* A process is created.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
TclpCreateProcess(interp, argc, argv, inputFile, outputFile, errorFile,
pidPtr)
Tcl_Interp *interp; /* Interpreter in which to leave errors that
* occurred when creating the child process.
* Error messages from the child process
* itself are sent to errorFile. */
int argc; /* Number of arguments in following array. */
char **argv; /* Array of argument strings. argv[0]
* contains the name of the executable
* converted to native format (using the
* Tcl_TranslateFileName call). Additional
* arguments have not been converted. */
TclFile inputFile; /* If non-NULL, gives the file to use as
* input for the child process. If inputFile
* file is not readable or is NULL, the child
* will receive no standard input. */
TclFile outputFile; /* If non-NULL, gives the file that
* receives output from the child process. If
* outputFile file is not writeable or is
* NULL, output from the child will be
* discarded. */
TclFile errorFile; /* If non-NULL, gives the file that
* receives errors from the child process. If
* errorFile file is not writeable or is NULL,
* errors from the child will be discarded.
* errorFile may be the same as outputFile. */
Tcl_Pid *pidPtr; /* If this procedure is successful, pidPtr
* is filled with the process id of the child
* process. */
{
TclFile errPipeIn, errPipeOut;
int joinThisError, count, status, fd;
char errSpace[200];
int pid;
errPipeIn = NULL;
errPipeOut = NULL;
pid = -1;
/*
* Create a pipe that the child can use to return error
* information if anything goes wrong.
*/
if (TclpCreatePipe(&errPipeIn, &errPipeOut) == 0) {
Tcl_AppendResult(interp, "couldn't create pipe: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
joinThisError = (errorFile == outputFile);
pid = vfork();
if (pid == 0) {
fd = GetFd(errPipeOut);
/*
* Set up stdio file handles for the child process.
*/
if (!SetupStdFile(inputFile, TCL_STDIN)
|| !SetupStdFile(outputFile, TCL_STDOUT)
|| (!joinThisError && !SetupStdFile(errorFile, TCL_STDERR))
|| (joinThisError &&
((dup2(1,2) == -1) ||
(fcntl(2, F_SETFD, 0) != 0)))) {
sprintf(errSpace,
"%dforked process couldn't set up input/output: ",
errno);
write(fd, errSpace, (size_t) strlen(errSpace));
_exit(1);
}
/*
* Close the input side of the error pipe.
*/
RestoreSignals();
execvp(argv[0], &argv[0]);
sprintf(errSpace, "%dcouldn't execute \"%.150s\": ", errno,
argv[0]);
write(fd, errSpace, (size_t) strlen(errSpace));
_exit(1);
}
if (pid == -1) {
Tcl_AppendResult(interp, "couldn't fork child process: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
/*
* Read back from the error pipe to see if the child started
* up OK. The info in the pipe (if any) consists of a decimal
* errno value followed by an error message.
*/
TclpCloseFile(errPipeOut);
errPipeOut = NULL;
fd = GetFd(errPipeIn);
count = read(fd, errSpace, (size_t) (sizeof(errSpace) - 1));
if (count > 0) {
char *end;
errSpace[count] = 0;
errno = strtol(errSpace, &end, 10);
Tcl_AppendResult(interp, end, Tcl_PosixError(interp),
(char *) NULL);
goto error;
}
TclpCloseFile(errPipeIn);
*pidPtr = (Tcl_Pid) pid;
return TCL_OK;
error:
if (pid != -1) {
/*
* Reap the child process now if an error occurred during its
* startup.
*/
Tcl_WaitPid((Tcl_Pid) pid, &status, WNOHANG);
}
if (errPipeIn) {
TclpCloseFile(errPipeIn);
}
if (errPipeOut) {
TclpCloseFile(errPipeOut);
}
return TCL_ERROR;
}
/*
*----------------------------------------------------------------------
*
* RestoreSignals --
*
* This procedure is invoked in a forked child process just before
* exec-ing a new program to restore all signals to their default
* settings.
*
* Results:
* None.
*
* Side effects:
* Signal settings get changed.
*
*----------------------------------------------------------------------
*/
static void
RestoreSignals()
{
#ifdef SIGABRT
signal(SIGABRT, SIG_DFL);
#endif
#ifdef SIGALRM
signal(SIGALRM, SIG_DFL);
#endif
#ifdef SIGFPE
signal(SIGFPE, SIG_DFL);
#endif
#ifdef SIGHUP
signal(SIGHUP, SIG_DFL);
#endif
#ifdef SIGILL
signal(SIGILL, SIG_DFL);
#endif
#ifdef SIGINT
signal(SIGINT, SIG_DFL);
#endif
#ifdef SIGPIPE
signal(SIGPIPE, SIG_DFL);
#endif
#ifdef SIGQUIT
signal(SIGQUIT, SIG_DFL);
#endif
#ifdef SIGSEGV
signal(SIGSEGV, SIG_DFL);
#endif
#ifdef SIGTERM
signal(SIGTERM, SIG_DFL);
#endif
#ifdef SIGUSR1
signal(SIGUSR1, SIG_DFL);
#endif
#ifdef SIGUSR2
signal(SIGUSR2, SIG_DFL);
#endif
#ifdef SIGCHLD
signal(SIGCHLD, SIG_DFL);
#endif
#ifdef SIGCONT
signal(SIGCONT, SIG_DFL);
#endif
#ifdef SIGTSTP
signal(SIGTSTP, SIG_DFL);
#endif
#ifdef SIGTTIN
signal(SIGTTIN, SIG_DFL);
#endif
#ifdef SIGTTOU
signal(SIGTTOU, SIG_DFL);
#endif
}
/*
*----------------------------------------------------------------------
*
* SetupStdFile --
*
* Set up stdio file handles for the child process, using the
* current standard channels if no other files are specified.
* If no standard channel is defined, or if no file is associated
* with the channel, then the corresponding standard fd is closed.
*
* Results:
* Returns 1 on success, or 0 on failure.
*
* Side effects:
* Replaces stdio fds.
*
*----------------------------------------------------------------------
*/
static int
SetupStdFile(file, type)
TclFile file; /* File to dup, or NULL. */
int type; /* One of TCL_STDIN, TCL_STDOUT, TCL_STDERR */
{
Tcl_Channel channel;
int fd;
int targetFd = 0; /* Initializations here needed only to */
int direction = 0; /* prevent warnings about using uninitialized
* variables. */
switch (type) {
case TCL_STDIN:
targetFd = 0;
direction = TCL_READABLE;
break;
case TCL_STDOUT:
targetFd = 1;
direction = TCL_WRITABLE;
break;
case TCL_STDERR:
targetFd = 2;
direction = TCL_WRITABLE;
break;
}
if (!file) {
channel = Tcl_GetStdChannel(type);
if (channel) {
file = TclpMakeFile(channel, direction);
}
}
if (file) {
fd = GetFd(file);
if (fd != targetFd) {
if (dup2(fd, targetFd) == -1) {
return 0;
}
/*
* Must clear the close-on-exec flag for the target FD, since
* some systems (e.g. Ultrix) do not clear the CLOEXEC flag on
* the target FD.
*/
fcntl(targetFd, F_SETFD, 0);
} else {
int result;
/*
* Since we aren't dup'ing the file, we need to explicitly clear
* the close-on-exec flag.
*/
result = fcntl(fd, F_SETFD, 0);
}
} else {
close(targetFd);
}
return 1;
}
/*
*----------------------------------------------------------------------
*
* TclpCreateCommandChannel --
*
* This function is called by the generic IO level to perform
* the platform specific channel initialization for a command
* channel.
*
* Results:
* Returns a new channel or NULL on failure.
*
* Side effects:
* Allocates a new channel.
*
*----------------------------------------------------------------------
*/
Tcl_Channel
TclpCreateCommandChannel(readFile, writeFile, errorFile, numPids, pidPtr)
TclFile readFile; /* If non-null, gives the file for reading. */
TclFile writeFile; /* If non-null, gives the file for writing. */
TclFile errorFile; /* If non-null, gives the file where errors
* can be read. */
int numPids; /* The number of pids in the pid array. */
Tcl_Pid *pidPtr; /* An array of process identifiers.
* Allocated by the caller, freed when
* the channel is closed or the processes
* are detached (in a background exec). */
{
char channelName[20];
int channelId;
PipeState *statePtr = (PipeState *) ckalloc((unsigned) sizeof(PipeState));
int mode;
statePtr->inFile = readFile;
statePtr->outFile = writeFile;
statePtr->errorFile = errorFile;
statePtr->numPids = numPids;
statePtr->pidPtr = pidPtr;
statePtr->isNonBlocking = 0;
mode = 0;
if (readFile) {
mode |= TCL_READABLE;
}
if (writeFile) {
mode |= TCL_WRITABLE;
}
/*
* Use one of the fds associated with the channel as the
* channel id.
*/
if (readFile) {
channelId = GetFd(readFile);
} else if (writeFile) {
channelId = GetFd(writeFile);
} else if (errorFile) {
channelId = GetFd(errorFile);
} else {
channelId = 0;
}
/*
* For backward compatibility with previous versions of Tcl, we
* use "file%d" as the base name for pipes even though it would
* be more natural to use "pipe%d".
*/
sprintf(channelName, "file%d", channelId);
statePtr->channel = Tcl_CreateChannel(&pipeChannelType, channelName,
(ClientData) statePtr, mode);
return statePtr->channel;
}
/*
*----------------------------------------------------------------------
*
* TclGetAndDetachPids --
*
* This procedure is invoked in the generic implementation of a
* background "exec" (An exec when invoked with a terminating "&")
* to store a list of the PIDs for processes in a command pipeline
* in interp->result and to detach the processes.
*
* Results:
* None.
*
* Side effects:
* Modifies interp->result. Detaches processes.
*
*----------------------------------------------------------------------
*/
void
TclGetAndDetachPids(interp, chan)
Tcl_Interp *interp;
Tcl_Channel chan;
{
PipeState *pipePtr;
Tcl_ChannelType *chanTypePtr;
int i;
char buf[20];
/*
* Punt if the channel is not a command channel.
*/
chanTypePtr = Tcl_GetChannelType(chan);
if (chanTypePtr != &pipeChannelType) {
return;
}
pipePtr = (PipeState *) Tcl_GetChannelInstanceData(chan);
for (i = 0; i < pipePtr->numPids; i++) {
sprintf(buf, "%ld", TclpGetPid(pipePtr->pidPtr[i]));
Tcl_AppendElement(interp, buf);
Tcl_DetachPids(1, &(pipePtr->pidPtr[i]));
}
if (pipePtr->numPids > 0) {
ckfree((char *) pipePtr->pidPtr);
pipePtr->numPids = 0;
}
}
/*
*----------------------------------------------------------------------
*
* PipeBlockModeProc --
*
* Helper procedure to set blocking and nonblocking modes on a
* pipe based channel. Invoked by generic IO level code.
*
* Results:
* 0 if successful, errno when failed.
*
* Side effects:
* Sets the device into blocking or non-blocking mode.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
static int
PipeBlockModeProc(instanceData, mode)
ClientData instanceData; /* Pipe state. */
int mode; /* The mode to set. Can be one of
* TCL_MODE_BLOCKING or
* TCL_MODE_NONBLOCKING. */
{
PipeState *psPtr = (PipeState *) instanceData;
int curStatus;
int fd;
#ifndef USE_FIONBIO
if (psPtr->inFile) {
fd = GetFd(psPtr->inFile);
curStatus = fcntl(fd, F_GETFL);
if (mode == TCL_MODE_BLOCKING) {
curStatus &= (~(O_NONBLOCK));
} else {
curStatus |= O_NONBLOCK;
}
if (fcntl(fd, F_SETFL, curStatus) < 0) {
return errno;
}
curStatus = fcntl(fd, F_GETFL);
}
if (psPtr->outFile) {
fd = GetFd(psPtr->outFile);
curStatus = fcntl(fd, F_GETFL);
if (mode == TCL_MODE_BLOCKING) {
curStatus &= (~(O_NONBLOCK));
} else {
curStatus |= O_NONBLOCK;
}
if (fcntl(fd, F_SETFL, curStatus) < 0) {
return errno;
}
}
#endif /* !FIONBIO */
#ifdef USE_FIONBIO
if (psPtr->inFile) {
fd = GetFd(psPtr->inFile);
if (mode == TCL_MODE_BLOCKING) {
curStatus = 0;
} else {
curStatus = 1;
}
if (ioctl(fd, (int) FIONBIO, &curStatus) < 0) {
return errno;
}
}
if (psPtr->outFile != NULL) {
fd = GetFd(psPtr->outFile);
if (mode == TCL_MODE_BLOCKING) {
curStatus = 0;
} else {
curStatus = 1;
}
if (ioctl(fd, (int) FIONBIO, &curStatus) < 0) {
return errno;
}
}
#endif /* USE_FIONBIO */
return 0;
}
/*
*----------------------------------------------------------------------
*
* PipeCloseProc --
*
* This procedure is invoked by the generic IO level to perform
* channel-type-specific cleanup when a command pipeline channel
* is closed.
*
* Results:
* 0 on success, errno otherwise.
*
* Side effects:
* Closes the command pipeline channel.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
static int
PipeCloseProc(instanceData, interp)
ClientData instanceData; /* The pipe to close. */
Tcl_Interp *interp; /* For error reporting. */
{
PipeState *pipePtr;
Tcl_Channel errChan;
int errorCode, result;
errorCode = 0;
result = 0;
pipePtr = (PipeState *) instanceData;
if (pipePtr->inFile) {
if (TclpCloseFile(pipePtr->inFile) < 0) {
errorCode = errno;
}
}
if (pipePtr->outFile) {
if ((TclpCloseFile(pipePtr->outFile) < 0) && (errorCode == 0)) {
errorCode = errno;
}
}
if (pipePtr->isNonBlocking || TclInExit()) {
/*
* If the channel is non-blocking or Tcl is being cleaned up, just
* detach the children PIDs, reap them (important if we are in a
* dynamic load module), and discard the errorFile.
*/
Tcl_DetachPids(pipePtr->numPids, pipePtr->pidPtr);
Tcl_ReapDetachedProcs();
if (pipePtr->errorFile) {
TclpCloseFile(pipePtr->errorFile);
}
} else {
/*
* Wrap the error file into a channel and give it to the cleanup
* routine.
*/
if (pipePtr->errorFile) {
errChan = Tcl_MakeFileChannel(
(ClientData) GetFd(pipePtr->errorFile), TCL_READABLE);
} else {
errChan = NULL;
}
result = TclCleanupChildren(interp, pipePtr->numPids, pipePtr->pidPtr,
errChan);
}
if (pipePtr->numPids != 0) {
ckfree((char *) pipePtr->pidPtr);
}
ckfree((char *) pipePtr);
if (errorCode == 0) {
return result;
}
return errorCode;
}
/*
*----------------------------------------------------------------------
*
* PipeInputProc --
*
* This procedure is invoked from the generic IO level to read
* input from a command pipeline based channel.
*
* Results:
* The number of bytes read is returned or -1 on error. An output
* argument contains a POSIX error code if an error occurs, or zero.
*
* Side effects:
* Reads input from the input device of the channel.
*
*----------------------------------------------------------------------
*/
static int
PipeInputProc(instanceData, buf, toRead, errorCodePtr)
ClientData instanceData; /* Pipe state. */
char *buf; /* Where to store data read. */
int toRead; /* How much space is available
* in the buffer? */
int *errorCodePtr; /* Where to store error code. */
{
PipeState *psPtr = (PipeState *) instanceData;
int bytesRead; /* How many bytes were actually
* read from the input device? */
*errorCodePtr = 0;
/*
* Assume there is always enough input available. This will block
* appropriately, and read will unblock as soon as a short read is
* possible, if the channel is in blocking mode. If the channel is
* nonblocking, the read will never block.
*/
bytesRead = read(GetFd(psPtr->inFile), buf, (size_t) toRead);
if (bytesRead > -1) {
return bytesRead;
}
*errorCodePtr = errno;
return -1;
}
/*
*----------------------------------------------------------------------
*
* PipeOutputProc--
*
* This procedure is invoked from the generic IO level to write
* output to a command pipeline based channel.
*
* Results:
* The number of bytes written is returned or -1 on error. An
* output argument contains a POSIX error code if an error occurred,
* or zero.
*
* Side effects:
* Writes output on the output device of the channel.
*
*----------------------------------------------------------------------
*/
static int
PipeOutputProc(instanceData, buf, toWrite, errorCodePtr)
ClientData instanceData; /* Pipe state. */
char *buf; /* The data buffer. */
int toWrite; /* How many bytes to write? */
int *errorCodePtr; /* Where to store error code. */
{
PipeState *psPtr = (PipeState *) instanceData;
int written;
*errorCodePtr = 0;
written = write(GetFd(psPtr->outFile), buf, (size_t) toWrite);
if (written > -1) {
return written;
}
*errorCodePtr = errno;
return -1;
}
/*
*----------------------------------------------------------------------
*
* PipeWatchProc --
*
* Initialize the notifier to watch the fds from this channel.
*
* Results:
* None.
*
* Side effects:
* Sets up the notifier so that a future event on the channel will
* be seen by Tcl.
*
*----------------------------------------------------------------------
*/
static void
PipeWatchProc(instanceData, mask)
ClientData instanceData; /* The pipe state. */
int mask; /* Events of interest; an OR-ed
* combination of TCL_READABLE,
* TCL_WRITABEL and TCL_EXCEPTION. */
{
PipeState *psPtr = (PipeState *) instanceData;
int newmask;
if (psPtr->inFile) {
newmask = mask & (TCL_READABLE | TCL_EXCEPTION);
if (newmask) {
Tcl_CreateFileHandler(GetFd(psPtr->inFile), mask,
(Tcl_FileProc *) Tcl_NotifyChannel,
(ClientData) psPtr->channel);
} else {
Tcl_DeleteFileHandler(GetFd(psPtr->inFile));
}
}
if (psPtr->outFile) {
newmask = mask & (TCL_WRITABLE | TCL_EXCEPTION);
if (newmask) {
Tcl_CreateFileHandler(GetFd(psPtr->outFile), mask,
(Tcl_FileProc *) Tcl_NotifyChannel,
(ClientData) psPtr->channel);
} else {
Tcl_DeleteFileHandler(GetFd(psPtr->outFile));
}
}
}
/*
*----------------------------------------------------------------------
*
* PipeGetHandleProc --
*
* Called from Tcl_GetChannelHandle to retrieve OS handles from
* inside a command pipeline based channel.
*
* Results:
* Returns TCL_OK with the fd in handlePtr, or TCL_ERROR if
* there is no handle for the specified direction.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static int
PipeGetHandleProc(instanceData, direction, handlePtr)
ClientData instanceData; /* The pipe state. */
int direction; /* TCL_READABLE or TCL_WRITABLE */
ClientData *handlePtr; /* Where to store the handle. */
{
PipeState *psPtr = (PipeState *) instanceData;
if (direction == TCL_READABLE && psPtr->inFile) {
*handlePtr = (ClientData) GetFd(psPtr->inFile);
return TCL_OK;
}
if (direction == TCL_WRITABLE && psPtr->outFile) {
*handlePtr = (ClientData) GetFd(psPtr->outFile);
return TCL_OK;
}
return TCL_ERROR;
}
/*
*----------------------------------------------------------------------
*
* Tcl_WaitPid --
*
* Implements the waitpid system call on Unix systems.
*
* Results:
* Result of calling waitpid.
*
* Side effects:
* Waits for a process to terminate.
*
*----------------------------------------------------------------------
*/
Tcl_Pid
Tcl_WaitPid(pid, statPtr, options)
Tcl_Pid pid;
int *statPtr;
int options;
{
int result;
pid_t real_pid;
real_pid = (pid_t) pid;
while (1) {
result = (int) waitpid(real_pid, statPtr, options);
if ((result != -1) || (errno != EINTR)) {
return (Tcl_Pid) result;
}
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_PidObjCmd --
*
* This procedure is invoked to process the "pid" Tcl command.
* See the user documentation for details on what it does.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* See the user documentation.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
int
Tcl_PidObjCmd(dummy, interp, objc, objv)
ClientData dummy; /* Not used. */
Tcl_Interp *interp; /* Current interpreter. */
int objc; /* Number of arguments. */
Tcl_Obj *CONST *objv; /* Argument strings. */
{
Tcl_Channel chan;
Tcl_ChannelType *chanTypePtr;
PipeState *pipePtr;
int i;
Tcl_Obj *resultPtr, *longObjPtr;
if (objc > 2) {
Tcl_WrongNumArgs(interp, 1, objv, "?channelId?");
return TCL_ERROR;
}
if (objc == 1) {
Tcl_SetLongObj(Tcl_GetObjResult(interp), (long) getpid());
} else {
chan = Tcl_GetChannel(interp, Tcl_GetStringFromObj(objv[1], NULL),
NULL);
if (chan == (Tcl_Channel) NULL) {
return TCL_ERROR;
}
chanTypePtr = Tcl_GetChannelType(chan);
if (chanTypePtr != &pipeChannelType) {
return TCL_OK;
}
pipePtr = (PipeState *) Tcl_GetChannelInstanceData(chan);
resultPtr = Tcl_GetObjResult(interp);
for (i = 0; i < pipePtr->numPids; i++) {
longObjPtr = Tcl_NewLongObj((long) TclpGetPid(pipePtr->pidPtr[i]));
Tcl_ListObjAppendElement(NULL, resultPtr, longObjPtr);
}
}
return TCL_OK;
}