archie/tcl7.3/tclUnixUtil.c
2024-05-27 16:13:40 +02:00

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/*
* tclUnixUtil.c --
*
* This file contains a collection of utility procedures that
* are present in the Tcl's UNIX core but not in the generic
* core. For example, they do file manipulation and process
* manipulation.
*
* Parts of this file are based on code contributed by Karl
* Lehenbauer, Mark Diekhans and Peter da Silva.
*
* Copyright (c) 1991-1993 The Regents of the University of California.
* All rights reserved.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
* OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
* CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*/
#ifndef lint
static char rcsid[] = "$Header: /user6/ouster/tcl/RCS/tclUnixUtil.c,v 1.45 93/10/23 14:52:10 ouster Exp $ SPRITE (Berkeley)";
#endif /* not lint */
#include "tclInt.h"
#include "tclUnix.h"
/*
* A linked list of the following structures is used to keep track
* of child processes that have been detached but haven't exited
* yet, so we can make sure that they're properly "reaped" (officially
* waited for) and don't lie around as zombies cluttering the
* system.
*/
typedef struct Detached {
int pid; /* Id of process that's been detached
* but isn't known to have exited. */
struct Detached *nextPtr; /* Next in list of all detached
* processes. */
} Detached;
static Detached *detList = NULL; /* List of all detached proceses. */
/*
* The following variables are used to keep track of all the open files
* in the process. These files can be shared across interpreters, so the
* information can't be put in the Interp structure.
*/
int tclNumFiles = 0; /* Number of entries in tclOpenFiles below.
* 0 means array hasn't been created yet. */
OpenFile **tclOpenFiles; /* Pointer to malloc-ed array of pointers
* to information about open files. Entry
* N corresponds to the file with fileno N.
* If an entry is NULL then the corresponding
* file isn't open. If tclOpenFiles is NULL
* it means no files have been used, so even
* stdin/stdout/stderr entries haven't been
* setup yet. */
/*
* Declarations for local procedures defined in this file:
*/
static int FileForRedirect _ANSI_ARGS_((Tcl_Interp *interp,
char *spec, int atOk, char *arg, int flags,
char *nextArg, int *skipPtr, int *closePtr));
static void MakeFileTable _ANSI_ARGS_((Interp *iPtr, int index));
static void RestoreSignals _ANSI_ARGS_((void));
/*
*----------------------------------------------------------------------
*
* Tcl_EvalFile --
*
* Read in a file and process the entire file as one gigantic
* Tcl command.
*
* Results:
* A standard Tcl result, which is either the result of executing
* the file or an error indicating why the file couldn't be read.
*
* Side effects:
* Depends on the commands in the file.
*
*----------------------------------------------------------------------
*/
int
Tcl_EvalFile(interp, fileName)
Tcl_Interp *interp; /* Interpreter in which to process file. */
char *fileName; /* Name of file to process. Tilde-substitution
* will be performed on this name. */
{
int fileId, result;
struct stat statBuf;
char *cmdBuffer, *oldScriptFile;
Interp *iPtr = (Interp *) interp;
Tcl_DString buffer;
oldScriptFile = iPtr->scriptFile;
iPtr->scriptFile = fileName;
fileName = Tcl_TildeSubst(interp, fileName, &buffer);
if (fileName == NULL) {
goto error;
}
fileId = open(fileName, O_RDONLY, 0);
if (fileId < 0) {
Tcl_AppendResult(interp, "couldn't read file \"", fileName,
"\": ", Tcl_PosixError(interp), (char *) NULL);
goto error;
}
if (fstat(fileId, &statBuf) == -1) {
Tcl_AppendResult(interp, "couldn't stat file \"", fileName,
"\": ", Tcl_PosixError(interp), (char *) NULL);
close(fileId);
goto error;
}
cmdBuffer = (char *) ckalloc((unsigned) statBuf.st_size+1);
if (read(fileId, cmdBuffer, (size_t) statBuf.st_size) != statBuf.st_size) {
Tcl_AppendResult(interp, "error in reading file \"", fileName,
"\": ", Tcl_PosixError(interp), (char *) NULL);
close(fileId);
ckfree(cmdBuffer);
goto error;
}
if (close(fileId) != 0) {
Tcl_AppendResult(interp, "error closing file \"", fileName,
"\": ", Tcl_PosixError(interp), (char *) NULL);
ckfree(cmdBuffer);
goto error;
}
cmdBuffer[statBuf.st_size] = 0;
result = Tcl_Eval(interp, cmdBuffer);
if (result == TCL_RETURN) {
result = TCL_OK;
}
if (result == TCL_ERROR) {
char msg[200];
/*
* Record information telling where the error occurred.
*/
sprintf(msg, "\n (file \"%.150s\" line %d)", fileName,
interp->errorLine);
Tcl_AddErrorInfo(interp, msg);
}
ckfree(cmdBuffer);
iPtr->scriptFile = oldScriptFile;
Tcl_DStringFree(&buffer);
return result;
error:
iPtr->scriptFile = oldScriptFile;
Tcl_DStringFree(&buffer);
return TCL_ERROR;
}
/*
*----------------------------------------------------------------------
*
* Tcl_DetachPids --
*
* This procedure is called to indicate that one or more child
* processes have been placed in background and will never be
* waited for; they should eventually be reaped by
* Tcl_ReapDetachedProcs.
*
* Results:
* None.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
void
Tcl_DetachPids(numPids, pidPtr)
int numPids; /* Number of pids to detach: gives size
* of array pointed to by pidPtr. */
int *pidPtr; /* Array of pids to detach. */
{
register Detached *detPtr;
int i;
for (i = 0; i < numPids; i++) {
detPtr = (Detached *) ckalloc(sizeof(Detached));
detPtr->pid = pidPtr[i];
detPtr->nextPtr = detList;
detList = detPtr;
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_ReapDetachedProcs --
*
* This procedure checks to see if any detached processes have
* exited and, if so, it "reaps" them by officially waiting on
* them. It should be called "occasionally" to make sure that
* all detached processes are eventually reaped.
*
* Results:
* None.
*
* Side effects:
* Processes are waited on, so that they can be reaped by the
* system.
*
*----------------------------------------------------------------------
*/
void
Tcl_ReapDetachedProcs()
{
register Detached *detPtr;
Detached *nextPtr, *prevPtr;
int status, result;
for (detPtr = detList, prevPtr = NULL; detPtr != NULL; ) {
result = waitpid(detPtr->pid, &status, WNOHANG);
if ((result == 0) || ((result == -1) && (errno != ECHILD))) {
prevPtr = detPtr;
detPtr = detPtr->nextPtr;
continue;
}
nextPtr = detPtr->nextPtr;
if (prevPtr == NULL) {
detList = detPtr->nextPtr;
} else {
prevPtr->nextPtr = detPtr->nextPtr;
}
ckfree((char *) detPtr);
detPtr = nextPtr;
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_CreatePipeline --
*
* Given an argc/argv array, instantiate a pipeline of processes
* as described by the argv.
*
* Results:
* The return value is a count of the number of new processes
* created, or -1 if an error occurred while creating the pipeline.
* *pidArrayPtr is filled in with the address of a dynamically
* allocated array giving the ids of all of the processes. It
* is up to the caller to free this array when it isn't needed
* anymore. If inPipePtr is non-NULL, *inPipePtr is filled in
* with the file id for the input pipe for the pipeline (if any):
* the caller must eventually close this file. If outPipePtr
* isn't NULL, then *outPipePtr is filled in with the file id
* for the output pipe from the pipeline: the caller must close
* this file. If errFilePtr isn't NULL, then *errFilePtr is filled
* with a file id that may be used to read error output after the
* pipeline completes.
*
* Side effects:
* Processes and pipes are created.
*
*----------------------------------------------------------------------
*/
int
Tcl_CreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr,
outPipePtr, errFilePtr)
Tcl_Interp *interp; /* Interpreter to use for error reporting. */
int argc; /* Number of entries in argv. */
char **argv; /* Array of strings describing commands in
* pipeline plus I/O redirection with <,
* <<, >, etc. Argv[argc] must be NULL. */
int **pidArrayPtr; /* Word at *pidArrayPtr gets filled in with
* address of array of pids for processes
* in pipeline (first pid is first process
* in pipeline). */
int *inPipePtr; /* If non-NULL, input to the pipeline comes
* from a pipe (unless overridden by
* redirection in the command). The file
* id with which to write to this pipe is
* stored at *inPipePtr. -1 means command
* specified its own input source. */
int *outPipePtr; /* If non-NULL, output to the pipeline goes
* to a pipe, unless overriden by redirection
* in the command. The file id with which to
* read frome this pipe is stored at
* *outPipePtr. -1 means command specified
* its own output sink. */
int *errFilePtr; /* If non-NULL, all stderr output from the
* pipeline will go to a temporary file
* created here, and a descriptor to read
* the file will be left at *errFilePtr.
* The file will be removed already, so
* closing this descriptor will be the end
* of the file. If this is NULL, then
* all stderr output goes to our stderr.
* If the pipeline specifies redirection
* then the fill will still be created
* but it will never get any data. */
{
int *pidPtr = NULL; /* Points to malloc-ed array holding all
* the pids of child processes. */
int numPids = 0; /* Actual number of processes that exist
* at *pidPtr right now. */
int cmdCount; /* Count of number of distinct commands
* found in argc/argv. */
char *input = NULL; /* If non-null, then this points to a
* string containing input data (specified
* via <<) to be piped to the first process
* in the pipeline. */
int inputId = -1; /* If >= 0, gives file id to use as input for
* first process in pipeline (specified via
* < or <@). */
int closeInput = 0; /* If non-zero, then must close inputId
* when cleaning up (zero means the file needs
* to stay open for some other reason). */
int outputId = -1; /* Writable file id for output from last
* command in pipeline (could be file or pipe).
* -1 means use stdout. */
int closeOutput = 0; /* Non-zero means must close outputId when
* cleaning up (similar to closeInput). */
int errorId = -1; /* Writable file id for error output from
* all commands in pipeline. -1 means use
* stderr. */
int closeError = 0; /* Non-zero means must close errorId when
* cleaning up. */
int pipeIds[2]; /* File ids for pipe that's being created. */
int firstArg, lastArg; /* Indexes of first and last arguments in
* current command. */
int skip; /* Number of arguments to skip (because they
* specify redirection). */
int maxFd; /* Highest known file descriptor (used to
* close off extraneous file descriptors in
* child process). */
int lastBar;
char *execName;
int i, j, pid;
char *p;
Tcl_DString buffer;
if (inPipePtr != NULL) {
*inPipePtr = -1;
}
if (outPipePtr != NULL) {
*outPipePtr = -1;
}
if (errFilePtr != NULL) {
*errFilePtr = -1;
}
pipeIds[0] = pipeIds[1] = -1;
/*
* First, scan through all the arguments to figure out the structure
* of the pipeline. Process all of the input and output redirection
* arguments and remove them from the argument list in the pipeline.
* Count the number of distinct processes (it's the number of "|"
* arguments plus one) but don't remove the "|" arguments.
*/
cmdCount = 1;
lastBar = -1;
for (i = 0; i < argc; i++) {
if ((argv[i][0] == '|') && (((argv[i][1] == 0))
|| ((argv[i][1] == '&') && (argv[i][2] == 0)))) {
if ((i == (lastBar+1)) || (i == (argc-1))) {
interp->result = "illegal use of | or |& in command";
return -1;
}
lastBar = i;
cmdCount++;
continue;
} else if (argv[i][0] == '<') {
if ((inputId >= 0) && closeInput) {
close(inputId);
}
inputId = -1;
skip = 1;
if (argv[i][1] == '<') {
input = argv[i]+2;
if (*input == 0) {
input = argv[i+1];
if (input == 0) {
Tcl_AppendResult(interp, "can't specify \"", argv[i],
"\" as last word in command", (char *) NULL);
goto error;
}
skip = 2;
}
} else {
input = 0;
inputId = FileForRedirect(interp, argv[i]+1, 1, argv[i],
O_RDONLY, argv[i+1], &skip, &closeInput);
if (inputId < 0) {
goto error;
}
}
} else if (argv[i][0] == '>') {
int append, useForStdErr, useForStdOut, mustClose, fd, atOk, flags;
skip = atOk = 1;
append = useForStdErr = 0;
useForStdOut = 1;
if (argv[i][1] == '>') {
p = argv[i] + 2;
append = 1;
atOk = 0;
flags = O_WRONLY|O_CREAT;
} else {
p = argv[i] + 1;
flags = O_WRONLY|O_CREAT|O_TRUNC;
}
if (*p == '&') {
useForStdErr = 1;
p++;
}
fd = FileForRedirect(interp, p, atOk, argv[i], flags, argv[i+1],
&skip, &mustClose);
if (fd < 0) {
goto error;
}
if (append) {
lseek(fd, 0L, 2);
}
/*
* Got the file descriptor. Now use it for standard output,
* standard error, or both, depending on the redirection.
*/
if (useForStdOut) {
if ((outputId > 0) && closeOutput) {
close(outputId);
}
outputId = fd;
closeOutput = mustClose;
}
if (useForStdErr) {
if ((errorId > 0) && closeError) {
close(errorId);
}
errorId = fd;
closeError = (useForStdOut) ? 0 : mustClose;
}
} else if ((argv[i][0] == '2') && (argv[i][1] == '>')) {
int append, atOk, flags;
if ((errorId > 0) && closeError) {
close(errorId);
}
skip = 1;
p = argv[i] + 2;
if (*p == '>') {
p++;
append = 1;
atOk = 0;
flags = O_WRONLY|O_CREAT;
} else {
append = 0;
atOk = 1;
flags = O_WRONLY|O_CREAT|O_TRUNC;
}
errorId = FileForRedirect(interp, p, atOk, argv[i], flags,
argv[i+1], &skip, &closeError);
if (errorId < 0) {
goto error;
}
if (append) {
lseek(errorId, 0L, 2);
}
} else {
continue;
}
for (j = i+skip; j < argc; j++) {
argv[j-skip] = argv[j];
}
argc -= skip;
i -= 1; /* Process next arg from same position. */
}
if (argc == 0) {
interp->result = "didn't specify command to execute";
return -1;
}
if (inputId < 0) {
if (input != NULL) {
char inName[L_tmpnam];
int length;
/*
* The input for the first process is immediate data coming from
* Tcl. Create a temporary file for it and put the data into the
* file.
*/
tmpnam(inName);
inputId = open(inName, O_RDWR|O_CREAT|O_TRUNC, 0600);
closeInput = 1;
if (inputId < 0) {
Tcl_AppendResult(interp,
"couldn't create input file for command: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
length = strlen(input);
if (write(inputId, input, (size_t) length) != length) {
Tcl_AppendResult(interp,
"couldn't write file input for command: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
if ((lseek(inputId, 0L, 0) == -1) || (unlink(inName) == -1)) {
Tcl_AppendResult(interp,
"couldn't reset or remove input file for command: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
} else if (inPipePtr != NULL) {
/*
* The input for the first process in the pipeline is to
* come from a pipe that can be written from this end.
*/
if (pipe(pipeIds) != 0) {
Tcl_AppendResult(interp,
"couldn't create input pipe for command: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
inputId = pipeIds[0];
closeInput = 1;
*inPipePtr = pipeIds[1];
pipeIds[0] = pipeIds[1] = -1;
}
}
/*
* Set up a pipe to receive output from the pipeline, if no other
* output sink has been specified.
*/
if ((outputId < 0) && (outPipePtr != NULL)) {
if (pipe(pipeIds) != 0) {
Tcl_AppendResult(interp,
"couldn't create output pipe: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
outputId = pipeIds[1];
closeOutput = 1;
*outPipePtr = pipeIds[0];
pipeIds[0] = pipeIds[1] = -1;
}
/*
* Set up the standard error output sink for the pipeline, if
* requested. Use a temporary file which is opened, then deleted.
* Could potentially just use pipe, but if it filled up it could
* cause the pipeline to deadlock: we'd be waiting for processes
* to complete before reading stderr, and processes couldn't complete
* because stderr was backed up.
*/
if (errFilePtr != NULL) {
char errName[L_tmpnam];
tmpnam(errName);
*errFilePtr = open(errName, O_RDONLY|O_CREAT|O_TRUNC, 0600);
if (*errFilePtr < 0) {
errFileError:
Tcl_AppendResult(interp,
"couldn't create error file for command: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
if (errorId < 0) {
errorId = open(errName, O_WRONLY|O_CREAT|O_TRUNC, 0600);
if (errorId < 0) {
goto errFileError;
}
closeError = 1;
}
if (unlink(errName) == -1) {
Tcl_AppendResult(interp,
"couldn't remove error file for command: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
}
/*
* Find the largest file descriptor used so far, so that we can
* clean up all the extraneous file descriptors in the child
* processes we create.
*/
maxFd = inputId;
if (outputId > maxFd) {
maxFd = outputId;
}
if (errorId > maxFd) {
maxFd = errorId;
}
if ((inPipePtr != NULL) && (*inPipePtr > maxFd)) {
maxFd = *inPipePtr;
}
if ((outPipePtr != NULL) && (*outPipePtr > maxFd)) {
maxFd = *outPipePtr;
}
if ((errFilePtr != NULL) && (*errFilePtr > maxFd)) {
maxFd = *errFilePtr;
}
/*
* Scan through the argc array, forking off a process for each
* group of arguments between "|" arguments.
*/
pidPtr = (int *) ckalloc((unsigned) (cmdCount * sizeof(int)));
for (i = 0; i < numPids; i++) {
pidPtr[i] = -1;
}
Tcl_ReapDetachedProcs();
for (firstArg = 0; firstArg < argc; numPids++, firstArg = lastArg+1) {
int joinThisError;
int curOutputId;
joinThisError = 0;
for (lastArg = firstArg; lastArg < argc; lastArg++) {
if (argv[lastArg][0] == '|') {
if (argv[lastArg][1] == 0) {
break;
}
if ((argv[lastArg][1] == '&') && (argv[lastArg][2] == 0)) {
joinThisError = 1;
break;
}
}
}
argv[lastArg] = NULL;
if (lastArg == argc) {
curOutputId = outputId;
} else {
if (pipe(pipeIds) != 0) {
Tcl_AppendResult(interp, "couldn't create pipe: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
curOutputId = pipeIds[1];
if (pipeIds[0] > maxFd) {
maxFd = pipeIds[0];
}
if (pipeIds[1] > maxFd) {
maxFd = pipeIds[1];
}
}
execName = Tcl_TildeSubst(interp, argv[firstArg], &buffer);
pid = fork();
if (pid == 0) {
char errSpace[200];
if (((inputId != -1) && (dup2(inputId, 0) == -1))
|| ((curOutputId != -1) && (dup2(curOutputId, 1) == -1))
|| (joinThisError && (dup2(1, 2) == -1))
|| (!joinThisError && (errorId != -1)
&& (dup2(errorId, 2) == -1))) {
char *err;
err = "forked process couldn't set up input/output\n";
write(errorId < 0 ? 2 : errorId, err, (size_t) strlen(err));
_exit(1);
}
for (i = 3; i <= maxFd; i++) {
close(i);
}
RestoreSignals();
execvp(execName, &argv[firstArg]);
sprintf(errSpace, "couldn't find \"%.150s\" to execute\n",
argv[firstArg]);
write(2, errSpace, (size_t) strlen(errSpace));
_exit(1);
}
Tcl_DStringFree(&buffer);
if (pid == -1) {
Tcl_AppendResult(interp, "couldn't fork child process: ",
Tcl_PosixError(interp), (char *) NULL);
goto error;
}
pidPtr[numPids] = pid;
/*
* Close off our copies of file descriptors that were set up for
* this child, then set up the input for the next child.
*/
if ((inputId != -1) && closeInput) {
close(inputId);
}
if ((curOutputId != -1) && (curOutputId != outputId)) {
close(curOutputId);
}
inputId = pipeIds[0];
closeInput = 1;
pipeIds[0] = pipeIds[1] = -1;
}
*pidArrayPtr = pidPtr;
/*
* All done. Cleanup open files lying around and then return.
*/
cleanup:
if ((inputId != -1) && closeInput) {
close(inputId);
}
if ((outputId != -1) && closeOutput) {
close(outputId);
}
if ((errorId != -1) && closeError) {
close(errorId);
}
return numPids;
/*
* An error occurred. There could have been extra files open, such
* as pipes between children. Clean them all up. Detach any child
* processes that have been created.
*/
error:
if ((inPipePtr != NULL) && (*inPipePtr != -1)) {
close(*inPipePtr);
*inPipePtr = -1;
}
if ((outPipePtr != NULL) && (*outPipePtr != -1)) {
close(*outPipePtr);
*outPipePtr = -1;
}
if ((errFilePtr != NULL) && (*errFilePtr != -1)) {
close(*errFilePtr);
*errFilePtr = -1;
}
if (pipeIds[0] != -1) {
close(pipeIds[0]);
}
if (pipeIds[1] != -1) {
close(pipeIds[1]);
}
if (pidPtr != NULL) {
for (i = 0; i < numPids; i++) {
if (pidPtr[i] != -1) {
Tcl_DetachPids(1, &pidPtr[i]);
}
}
ckfree((char *) pidPtr);
}
numPids = -1;
goto cleanup;
}
/*
*----------------------------------------------------------------------
*
* FileForRedirect --
*
* This procedure does much of the work of parsing redirection
* operators. It handles "@" if specified and allowed, and a file
* name, and opens the file if necessary.
*
* Results:
* The return value is the descriptor number for the file. If an
* error occurs then -1 is returned and an error message is left
* in interp->result. Several arguments are side-effected; see
* the argument list below for details.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static int
FileForRedirect(interp, spec, atOk, arg, flags, nextArg, skipPtr, closePtr)
Tcl_Interp *interp; /* Intepreter to use for error
* reporting. */
register char *spec; /* Points to character just after
* redirection character. */
int atOk; /* Non-zero means '@' notation is
* OK, zero means it isn't. */
char *arg; /* Pointer to entire argument
* containing spec: used for error
* reporting. */
int flags; /* Flags to use for opening file. */
char *nextArg; /* Next argument in argc/argv
* array, if needed for file name.
* May be NULL. */
int *skipPtr; /* This value is incremented if
* nextArg is used for redirection
* spec. */
int *closePtr; /* This value is set to 1 if the file
* that's returned must be closed, 0
* if it was specified with "@" so
* it must be left open. */
{
int writing = (flags & O_WRONLY);
FILE *f;
int fd;
if (atOk && (*spec == '@')) {
spec++;
if (*spec == 0) {
spec = nextArg;
if (spec == NULL) {
goto badLastArg;
}
*skipPtr += 1;
}
if (Tcl_GetOpenFile(interp, spec, writing, 1, &f) != TCL_OK) {
return -1;
}
*closePtr = 0;
fd = fileno(f);
} else {
if (*spec == 0) {
spec = nextArg;
if (spec == NULL) {
goto badLastArg;
}
*skipPtr += 1;
}
fd = open(spec, flags, 0666);
if (fd < 0) {
Tcl_AppendResult(interp, "couldn't ",
(writing) ? "write" : "read", " file \"", spec, "\": ",
Tcl_PosixError(interp), (char *) NULL);
return -1;
}
*closePtr = 1;
}
return fd;
badLastArg:
Tcl_AppendResult(interp, "can't specify \"", arg,
"\" as last word in command", (char *) NULL);
return -1;
}
/*
*----------------------------------------------------------------------
*
* 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
}
/*
*----------------------------------------------------------------------
*
* Tcl_PosixError --
*
* This procedure is typically called after UNIX kernel calls
* return errors. It stores machine-readable information about
* the error in $errorCode returns an information string for
* the caller's use.
*
* Results:
* The return value is a human-readable string describing the
* error, as returned by strerror.
*
* Side effects:
* The global variable $errorCode is reset.
*
*----------------------------------------------------------------------
*/
char *
Tcl_PosixError(interp)
Tcl_Interp *interp; /* Interpreter whose $errorCode variable
* is to be changed. */
{
char *id, *msg;
id = Tcl_ErrnoId();
msg = strerror(errno);
Tcl_SetErrorCode(interp, "POSIX", id, msg, (char *) NULL);
return msg;
}
/*
*----------------------------------------------------------------------
*
* MakeFileTable --
*
* Create or enlarge the file table for the interpreter, so that
* there is room for a given index.
*
* Results:
* None.
*
* Side effects:
* The file table for iPtr will be created if it doesn't exist
* (and entries will be added for stdin, stdout, and stderr).
* If it already exists, then it will be grown if necessary.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
static void
MakeFileTable(iPtr, index)
Interp *iPtr; /* Interpreter whose table of files is
* to be manipulated. */
int index; /* Make sure table is large enough to
* hold at least this index. */
{
/*
* If the table doesn't even exist, then create it and initialize
* entries for standard files.
*/
if (tclNumFiles == 0) {
OpenFile *oFilePtr;
int i;
if (index < 2) {
tclNumFiles = 3;
} else {
tclNumFiles = index+1;
}
tclOpenFiles = (OpenFile **) ckalloc((unsigned)
((tclNumFiles)*sizeof(OpenFile *)));
for (i = tclNumFiles-1; i >= 0; i--) {
tclOpenFiles[i] = NULL;
}
oFilePtr = (OpenFile *) ckalloc(sizeof(OpenFile));
oFilePtr->f = stdin;
oFilePtr->f2 = NULL;
oFilePtr->permissions = TCL_FILE_READABLE;
oFilePtr->numPids = 0;
oFilePtr->pidPtr = NULL;
oFilePtr->errorId = -1;
tclOpenFiles[0] = oFilePtr;
oFilePtr = (OpenFile *) ckalloc(sizeof(OpenFile));
oFilePtr->f = stdout;
oFilePtr->f2 = NULL;
oFilePtr->permissions = TCL_FILE_WRITABLE;
oFilePtr->numPids = 0;
oFilePtr->pidPtr = NULL;
oFilePtr->errorId = -1;
tclOpenFiles[1] = oFilePtr;
oFilePtr = (OpenFile *) ckalloc(sizeof(OpenFile));
oFilePtr->f = stderr;
oFilePtr->f2 = NULL;
oFilePtr->permissions = TCL_FILE_WRITABLE;
oFilePtr->numPids = 0;
oFilePtr->pidPtr = NULL;
oFilePtr->errorId = -1;
tclOpenFiles[2] = oFilePtr;
} else if (index >= tclNumFiles) {
int newSize;
OpenFile **newPtrArray;
int i;
newSize = index+1;
newPtrArray = (OpenFile **) ckalloc((unsigned)
((newSize)*sizeof(OpenFile *)));
memcpy((VOID *) newPtrArray, (VOID *) tclOpenFiles,
tclNumFiles*sizeof(OpenFile *));
for (i = tclNumFiles; i < newSize; i++) {
newPtrArray[i] = NULL;
}
ckfree((char *) tclOpenFiles);
tclNumFiles = newSize;
tclOpenFiles = newPtrArray;
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_EnterFile --
*
* This procedure is used to enter an already-open file into the
* file table for an interpreter so that the file can be read
* and written with Tcl commands.
*
* Results:
* There is no return value, but interp->result is set to
* hold Tcl's id for the open file, such as "file4".
*
* Side effects:
* "File" is added to the files accessible from interp.
*
*----------------------------------------------------------------------
*/
void
Tcl_EnterFile(interp, file, permissions)
Tcl_Interp *interp; /* Interpreter in which to make file
* available. */
FILE *file; /* File to make available in interp. */
int permissions; /* Ops that may be done on file: OR-ed
* combinination of TCL_FILE_READABLE and
* TCL_FILE_WRITABLE. */
{
Interp *iPtr = (Interp *) interp;
int fd;
register OpenFile *oFilePtr;
fd = fileno(file);
if (fd >= tclNumFiles) {
MakeFileTable(iPtr, fd);
}
oFilePtr = tclOpenFiles[fd];
/*
* It's possible that there already appears to be a file open in
* the slot. This could happen, for example, if the application
* closes a file behind our back so that we don't have a chance
* to clean up. This is probably a bad idea, but if it happens
* just discard the information in the old record (hopefully the
* application is smart enough to have really cleaned everything
* up right).
*/
if (oFilePtr == NULL) {
oFilePtr = (OpenFile *) ckalloc(sizeof(OpenFile));
tclOpenFiles[fd] = oFilePtr;
}
oFilePtr->f = file;
oFilePtr->f2 = NULL;
oFilePtr->permissions = permissions;
oFilePtr->numPids = 0;
oFilePtr->pidPtr = NULL;
oFilePtr->errorId = -1;
if (fd <= 2) {
if (fd == 0) {
interp->result = "stdin";
} else if (fd == 1) {
interp->result = "stdout";
} else {
interp->result = "stderr";
}
} else {
sprintf(interp->result, "file%d", fd);
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_GetOpenFile --
*
* Given a string identifier for an open file, find the corresponding
* open file structure, if there is one.
*
* Results:
* A standard Tcl return value. If the open file is successfully
* located and meets any usage check requested by checkUsage, TCL_OK
* is returned and *filePtr is modified to hold a pointer to its
* FILE structure. If an error occurs then TCL_ERROR is returned
* and interp->result contains an error message.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_GetOpenFile(interp, string, forWriting, checkUsage, filePtr)
Tcl_Interp *interp; /* Interpreter in which to find file. */
char *string; /* String that identifies file. */
int forWriting; /* 1 means the file is going to be used
* for writing, 0 means for reading. */
int checkUsage; /* 1 means verify that the file was opened
* in a mode that allows the access specified
* by "forWriting". */
FILE **filePtr; /* Store pointer to FILE structure here. */
{
OpenFile *oFilePtr;
int fd = 0; /* Initial value needed only to stop compiler
* warnings. */
Interp *iPtr = (Interp *) interp;
if ((string[0] == 'f') && (string[1] == 'i') && (string[2] == 'l')
& (string[3] == 'e')) {
char *end;
fd = strtoul(string+4, &end, 10);
if ((end == string+4) || (*end != 0)) {
goto badId;
}
} else if ((string[0] == 's') && (string[1] == 't')
&& (string[2] == 'd')) {
if (strcmp(string+3, "in") == 0) {
fd = 0;
} else if (strcmp(string+3, "out") == 0) {
fd = 1;
} else if (strcmp(string+3, "err") == 0) {
fd = 2;
} else {
goto badId;
}
} else {
badId:
Tcl_AppendResult(interp, "bad file identifier \"", string,
"\"", (char *) NULL);
return TCL_ERROR;
}
if (fd >= tclNumFiles) {
if ((tclNumFiles == 0) && (fd <= 2)) {
MakeFileTable(iPtr, fd);
} else {
notOpen:
Tcl_AppendResult(interp, "file \"", string, "\" isn't open",
(char *) NULL);
return TCL_ERROR;
}
}
oFilePtr = tclOpenFiles[fd];
if (oFilePtr == NULL) {
goto notOpen;
}
if (forWriting) {
if (checkUsage && !(oFilePtr->permissions & TCL_FILE_WRITABLE)) {
Tcl_AppendResult(interp, "\"", string,
"\" wasn't opened for writing", (char *) NULL);
return TCL_ERROR;
}
if (oFilePtr->f2 != NULL) {
*filePtr = oFilePtr->f2;
} else {
*filePtr = oFilePtr->f;
}
} else {
if (checkUsage && !(oFilePtr->permissions & TCL_FILE_READABLE)) {
Tcl_AppendResult(interp, "\"", string,
"\" wasn't opened for reading", (char *) NULL);
return TCL_ERROR;
}
*filePtr = oFilePtr->f;
}
return TCL_OK;
}
/*
*----------------------------------------------------------------------
*
* Tcl_FilePermissions --
*
* Given a FILE * pointer, return the read/write permissions
* associated with the open file.
*
* Results:
* If file is currently open, the return value is an OR-ed
* combination of TCL_FILE_READABLE and TCL_FILE_WRITABLE,
* which indicates the operations permitted on the open file.
* If the file isn't open then the return value is -1.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
Tcl_FilePermissions(file)
FILE *file; /* File for which permissions are wanted. */
{
register OpenFile *oFilePtr;
int i, fd;
/*
* First try the entry in tclOpenFiles given by the file descriptor
* for the file. If that doesn't match then search all the entries
* in tclOpenFiles.
*/
if (file != NULL) {
fd = fileno(file);
if (fd < tclNumFiles) {
oFilePtr = tclOpenFiles[fd];
if ((oFilePtr != NULL) && (oFilePtr->f == file)) {
return oFilePtr->permissions;
}
}
}
for (i = 0; i < tclNumFiles; i++) {
oFilePtr = tclOpenFiles[i];
if (oFilePtr == NULL) {
continue;
}
if ((oFilePtr->f == file) || (oFilePtr->f2 == file)) {
return oFilePtr->permissions;
}
}
return -1;
}
/*
*----------------------------------------------------------------------
*
* TclOpen, etc. --
*
* Below are a bunch of procedures that are used by Tcl instead
* of system calls. Each of the procedures executes the
* corresponding system call and retries automatically
* if the system call was interrupted by a signal.
*
* Results:
* Whatever the system call would normally return.
*
* Side effects:
* Whatever the system call would normally do.
*
* NOTE:
* This should be the last page of this file, since it undefines
* the macros that redirect read etc. to the procedures below.
*
*----------------------------------------------------------------------
*/
#undef open
int
TclOpen(path, oflag, mode)
char *path;
int oflag;
int mode;
{
int result;
while (1) {
result = open(path, oflag, mode);
if ((result != -1) || (errno != EINTR)) {
return result;
}
}
}
#undef read
int
TclRead(fd, buf, numBytes)
int fd;
VOID *buf;
size_t numBytes;
{
int result;
while (1) {
result = read(fd, buf, (size_t) numBytes);
if ((result != -1) || (errno != EINTR)) {
return result;
}
}
}
#undef waitpid
extern pid_t waitpid _ANSI_ARGS_((pid_t pid, int *stat_loc, int options));
/*
* Note: the #ifdef below is needed to avoid compiler errors on systems
* that have ANSI compilers and also define pid_t to be short. The
* problem is a complex one having to do with argument type promotion.
*/
#ifdef _USING_PROTOTYPES_
int
TclWaitpid _ANSI_ARGS_((pid_t pid, int *statPtr, int options))
#else
int
TclWaitpid(pid, statPtr, options)
pid_t pid;
int *statPtr;
int options;
#endif /* _USING_PROTOTYPES_ */
{
int result;
while (1) {
result = waitpid(pid, statPtr, options);
if ((result != -1) || (errno != EINTR)) {
return result;
}
}
}
#undef write
int
TclWrite(fd, buf, numBytes)
int fd;
VOID *buf;
size_t numBytes;
{
int result;
while (1) {
result = write(fd, buf, (size_t) numBytes);
if ((result != -1) || (errno != EINTR)) {
return result;
}
}
}