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|
/*
* (c) 2008 Steve Bennett <steveb@workware.net.au>
*
* Implements the exec command for Jim
*
* Based on code originally from Tcl 6.7:
*
* Copyright 1987-1991 Regents of the University of California
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
* fee is hereby granted, provided that the above copyright
* notice appear in all copies. The University of California
* makes no representations about the suitability of this
* software for any purpose. It is provided "as is" without
* express or implied warranty.
*/
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/wait.h>
#include "jim.h"
#include "jim-subcmd.h"
#include "jim-signal.h"
/* These two could be moved into the Tcl core */
static void Jim_SetResultErrno(Jim_Interp *interp, const char *msg)
{
Jim_SetResultFormatted(interp, "%s: %s", msg, strerror(errno));
}
static void Jim_RemoveTrailingNewline(Jim_Obj *objPtr)
{
int len;
const char *s = Jim_GetString(objPtr, &len);
if (len > 0 && s[len-1] == '\n') {
objPtr->length--;
objPtr->bytes[objPtr->length] = '\0';
}
}
/**
* Read from 'fd' and append the data to strObj
* Returns JIM_OK if OK, or JIM_ERR on error.
*/
static int JimAppendStreamToString(Jim_Interp *interp, int fd, Jim_Obj *strObj)
{
while (1) {
char buffer[256];
int count;
count = read(fd, buffer, sizeof(buffer));
if (count == 0) {
Jim_RemoveTrailingNewline(strObj);
return JIM_OK;
}
if (count < 0) {
return JIM_ERR;
}
Jim_AppendString(interp, strObj, buffer, count);
}
}
/*
* If the last character of the result is a newline, then remove
* the newline character (the newline would just confuse things).
*
* Note: Ideally we could do this by just reducing the length of stringrep
* by 1, but there is no API for this :-(
*/
static void JimTrimTrailingNewline(Jim_Interp *interp)
{
int len;
const char *p = Jim_GetString(Jim_GetResult(interp), &len);
if (len > 0 && p[len - 1] == '\n') {
Jim_SetResultString(interp, p, len - 1);
}
}
/*
* Create error messages for unusual process exits. An
* extra newline gets appended to each error message, but
* it gets removed below (in the same fashion that an
* extra newline in the command's output is removed).
*/
static int JimCheckWaitStatus(Jim_Interp *interp, int pid, int waitStatus)
{
/* REVISIT: Child exit status is lost here */
if (WIFEXITED(waitStatus) && WEXITSTATUS(waitStatus) == 0) {
return JIM_OK;
}
else if (WIFSIGNALED(waitStatus)) {
#ifdef jim_ext_signal
Jim_SetResultFormatted(interp, "child killed by signal %s", Jim_SignalId(WTERMSIG(waitStatus)));
#else
Jim_SetResultFormatted(interp, "child killed by signal %d", WTERMSIG(waitStatus));
#endif
}
else if (WIFSTOPPED(waitStatus)) {
Jim_SetResultString(interp, "child suspended", -1);
}
return JIM_ERR;
}
#if defined(HAVE_FORK) && !defined(HAVE_NO_FORK)
static int Jim_CreatePipeline(Jim_Interp *interp, int argc, Jim_Obj *const *argv,
int **pidArrayPtr, int *inPipePtr, int *outPipePtr, int *errFilePtr);
static void JimDetachPids(Jim_Interp *interp, int numPids, int *pidPtr);
static int
Jim_CleanupChildren(Jim_Interp *interp, int numPids, int *pidPtr, int errorId);
static int
Jim_ExecCmd(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
int outputId; /* File id for output pipe. -1
* means command overrode. */
int errorId; /* File id for temporary file
* containing error output. */
int *pidPtr;
int numPids, result;
/*
* See if the command is to be run in background; if so, create
* the command, detach it, and return.
*/
if (argc > 1 && Jim_CompareStringImmediate(interp, argv[argc - 1], "&")) {
Jim_Obj *listObj;
int i;
argc--;
numPids = Jim_CreatePipeline(interp, argc-1, argv+1, &pidPtr, NULL, NULL, NULL);
if (numPids < 0) {
return JIM_ERR;
}
/* The return value is a list of the pids */
listObj = Jim_NewListObj(interp, NULL, 0);
for (i = 0; i < numPids; i++) {
Jim_ListAppendElement(interp, listObj, Jim_NewIntObj(interp, pidPtr[i]));
}
Jim_SetResult(interp, listObj);
JimDetachPids(interp, numPids, pidPtr);
Jim_Free(pidPtr);
return JIM_OK;
}
/*
* Create the command's pipeline.
*/
numPids = Jim_CreatePipeline(interp, argc-1, argv+1, &pidPtr, (int *) NULL, &outputId, &errorId);
if (numPids < 0) {
return JIM_ERR;
}
/*
* Read the child's output (if any) and put it into the result.
*/
Jim_SetResultString(interp, "", 0);
result = JIM_OK;
if (outputId != -1) {
result = JimAppendStreamToString(interp, outputId, Jim_GetResult(interp));
if (result < 0) {
Jim_SetResultErrno(interp, "error reading from output pipe");
}
close(outputId);
}
if (Jim_CleanupChildren(interp, numPids, pidPtr, errorId) != JIM_OK) {
result = JIM_ERR;
}
return result;
}
/*
* Data structures of the following type are used by JimFork and
* JimWaitPids to keep track of child processes.
*/
typedef struct {
int pid; /* Process id of child. */
int status; /* Status returned when child exited or suspended. */
int flags; /* Various flag bits; see below for definitions. */
} WaitInfo;
/*
* Flag bits in WaitInfo structures:
*
* WI_READY - Non-zero means process has exited or
* suspended since it was forked or last
* returned by JimWaitPids.
* WI_DETACHED - Non-zero means no-one cares about the
* process anymore. Ignore it until it
* exits, then forget about it.
*/
#define WI_READY 1
#define WI_DETACHED 2
/* REVISIT: Should be per-interpreter */
static WaitInfo *waitTable = NULL;
static int waitTableSize = 0; /* Total number of entries available in waitTable. */
static int waitTableUsed = 0; /* Number of entries in waitTable that
* are actually in use right now. Active
* entries are always at the beginning
* of the table. */
#define WAIT_TABLE_GROW_BY 4
/*
*----------------------------------------------------------------------
*
* JimFork --
*
* Create a new process using the vfork system call, and keep
* track of it for "safe" waiting with JimWaitPids.
*
* Results:
* The return value is the value returned by the vfork system
* call (0 means child, > 0 means parent (value is child id),
* < 0 means error).
*
* Side effects:
* A new process is created, and an entry is added to an internal
* table of child processes if the process is created successfully.
*
*----------------------------------------------------------------------
*/
static int
JimFork(void)
{
WaitInfo *waitPtr;
pid_t pid;
/*
* Disable SIGPIPE signals: if they were allowed, this process
* might go away unexpectedly if children misbehave. This code
* can potentially interfere with other application code that
* expects to handle SIGPIPEs; what's really needed is an
* arbiter for signals to allow them to be "shared".
*/
if (waitTable == NULL) {
(void) signal(SIGPIPE, SIG_IGN);
}
/*
* Enlarge the wait table if there isn't enough space for a new
* entry.
*/
if (waitTableUsed == waitTableSize) {
waitTableSize += WAIT_TABLE_GROW_BY;
waitTable = (WaitInfo *)realloc(waitTable, waitTableSize * sizeof(WaitInfo));
}
/*
* Make a new process and enter it into the table if the fork
* is successful.
*/
waitPtr = &waitTable[waitTableUsed];
pid = fork();
if (pid > 0) {
waitPtr->pid = pid;
waitPtr->flags = 0;
waitTableUsed++;
}
return pid;
}
/*
*----------------------------------------------------------------------
*
* JimWaitPids --
*
* This procedure is used to wait for one or more processes created
* by JimFork to exit or suspend. It records information about
* all processes that exit or suspend, even those not waited for,
* so that later waits for them will be able to get the status
* information.
*
* Results:
* -1 is returned if there is an error in the wait kernel call.
* Otherwise the pid of an exited/suspended process from *pidPtr
* is returned and *statusPtr is set to the status value returned
* by the wait kernel call.
*
* Side effects:
* Doesn't return until one of the pids at *pidPtr exits or suspends.
*
*----------------------------------------------------------------------
*/
static int
JimWaitPids(int numPids, int *pidPtr, int *statusPtr)
{
int i, count, pid;
WaitInfo *waitPtr;
int anyProcesses;
int status;
while (1) {
/*
* Scan the table of child processes to see if one of the
* specified children has already exited or suspended. If so,
* remove it from the table and return its status.
*/
anyProcesses = 0;
for (waitPtr = waitTable, count = waitTableUsed; count > 0; waitPtr++, count--) {
for (i = 0; i < numPids; i++) {
if (pidPtr[i] != waitPtr->pid) {
continue;
}
anyProcesses = 1;
if (waitPtr->flags & WI_READY) {
*statusPtr = *((int *) &waitPtr->status);
pid = waitPtr->pid;
if (WIFEXITED(waitPtr->status) || WIFSIGNALED(waitPtr->status)) {
if (waitPtr != &waitTable[waitTableUsed-1]) {
*waitPtr = waitTable[waitTableUsed-1];
}
waitTableUsed--;
}
else {
waitPtr->flags &= ~WI_READY;
}
return pid;
}
}
}
/*
* Make sure that the caller at least specified one valid
* process to wait for.
*/
if (!anyProcesses) {
errno = ECHILD;
return -1;
}
/*
* Wait for a process to exit or suspend, then update its
* entry in the table and go back to the beginning of the
* loop to see if it's one of the desired processes.
*/
pid = wait(&status);
if (pid < 0) {
return pid;
}
for (waitPtr = waitTable, count = waitTableUsed; ; waitPtr++, count--) {
if (count == 0) {
break; /* Ignore unknown processes. */
}
if (pid != waitPtr->pid) {
continue;
}
/*
* If the process has been detached, then ignore anything
* other than an exit, and drop the entry on exit.
*/
if (waitPtr->flags & WI_DETACHED) {
if (WIFEXITED(status) || WIFSIGNALED(status)) {
*waitPtr = waitTable[waitTableUsed-1];
waitTableUsed--;
}
} else {
waitPtr->status = status;
waitPtr->flags |= WI_READY;
}
break;
}
}
}
/*
*----------------------------------------------------------------------
*
* JimDetachPids --
*
* This procedure is called to indicate that one or more child
* processes have been placed in background and are no longer
* cared about. They should be ignored in future calls to
* JimWaitPids.
*
* Results:
* None.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static void JimDetachPids(Jim_Interp *interp, int numPids, int *pidPtr)
{
WaitInfo *waitPtr;
int i, count, pid;
for (i = 0; i < numPids; i++) {
pid = pidPtr[i];
for (waitPtr = waitTable, count = waitTableUsed; count > 0; waitPtr++, count--) {
if (pid != waitPtr->pid) {
continue;
}
/*
* If the process has already exited then destroy its
* table entry now.
*/
if ((waitPtr->flags & WI_READY) && (WIFEXITED(waitPtr->status) || WIFSIGNALED(waitPtr->status))) {
*waitPtr = waitTable[waitTableUsed-1];
waitTableUsed--;
} else {
waitPtr->flags |= WI_DETACHED;
}
goto nextPid;
}
Jim_Panic(interp, "Jim_Detach couldn't find process");
nextPid:
continue;
}
}
/*
*----------------------------------------------------------------------
*
* Jim_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.
*
*----------------------------------------------------------------------
*/
static int
Jim_CreatePipeline(Jim_Interp *interp, int argc, Jim_Obj *const *argv, int **pidArrayPtr, int *inPipePtr, int *outPipePtr, int *errFilePtr)
{
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. */
const char *input = NULL; /* Describes input for pipeline, depending
* on "inputFile". NULL means take input
* from stdin/pipe. */
#define FILE_NAME 0 /* input/output: filename */
#define FILE_APPEND 1 /* output only: filename, append */
#define FILE_HANDLE 2 /* input/output: filehandle */
#define FILE_TEXT 3 /* input only: input is actual text */
int inputFile = FILE_NAME; /* 1 means input is name of input file.
* 2 means input is filehandle name.
* 0 means input holds actual
* text to be input to command. */
int outputFile = FILE_NAME; /* 0 means output is the name of output file.
* 1 means output is the name of output file, and append.
* 2 means output is filehandle name.
* All this is ignored if output is NULL
*/
int errorFile = FILE_NAME; /* 0 means error is the name of error file.
* 1 means error is the name of error file, and append.
* 2 means error is filehandle name.
* All this is ignored if error is NULL
*/
const char *output = NULL; /* Holds name of output file to pipe to,
* or NULL if output goes to stdout/pipe. */
const char *error = NULL; /* Holds name of stderr file to pipe to,
* or NULL if stderr goes to stderr/pipe. */
int inputId = -1; /* Readable file id input to current command in
* pipeline (could be file or pipe). -1
* means use stdin. */
int outputId = -1; /* Writable file id for output from current
* command in pipeline (could be file or pipe).
* -1 means use stdout. */
int errorId = -1; /* Writable file id for all standard error
* output from all commands in pipeline. -1
* means use stderr. */
int lastOutputId = -1; /* Write file id for output from last command
* in pipeline (could be file or pipe).
* -1 means use stdout. */
int pipeIds[2]; /* File ids for pipe that's being created. */
int firstArg, lastArg; /* Indexes of first and last arguments in
* current command. */
int lastBar;
char *execName;
int i, pid;
/* Holds the args which will be used to exec */
char **arg_array = Jim_Alloc(sizeof(*arg_array) * (argc + 1));
int arg_count = 0;
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. Count the number of distinct processes (it's the
* number of "|" arguments). If there are "<", "<<", or ">" arguments
* then make note of input and output redirection and remove these
* arguments and the arguments that follow them.
*/
cmdCount = 1;
lastBar = -1;
for (i = 0; i < argc; i++) {
const char *arg = Jim_GetString(argv[i], NULL);
if (arg[0] == '<') {
inputFile = FILE_NAME;
input = arg + 1;
if (*input == '<') {
inputFile = FILE_TEXT;
input++;
}
else if (*input == '@') {
inputFile = FILE_HANDLE;
input++;
}
if (!*input && ++i < argc) {
input = Jim_GetString(argv[i], NULL);
}
}
else if (arg[0] == '>') {
int dup_error = 0;
outputFile = FILE_NAME;
output = arg + 1;
if (*output == '>') {
outputFile = FILE_APPEND;
output++;
}
if (*output == '&') {
/* Redirect stderr too */
output++;
dup_error = 1;
}
if (*output == '@') {
outputFile = FILE_HANDLE;
output++;
}
if (!*output && ++i < argc) {
output = Jim_GetString(argv[i], NULL);
}
if (dup_error) {
errorFile = outputFile;
error = output;
}
}
else if (arg[0] == '2' && arg[1] == '>') {
error = arg + 2;
errorFile = FILE_NAME;
if (*error == '@') {
errorFile = FILE_HANDLE;
error++;
}
else if (*error == '>') {
errorFile = FILE_APPEND;
error++;
}
if (!*error && ++i < argc) {
error = Jim_GetString(argv[i], NULL);
}
}
else {
if (strcmp(arg, "|") == 0 || strcmp(arg, "|&") == 0) {
if (i == lastBar + 1 || i == argc - 1) {
Jim_SetResultString(interp, "illegal use of | or |& in command", -1);
Jim_Free(arg_array);
return -1;
}
lastBar = i;
cmdCount++;
}
/* Either |, |& or a "normal" arg, so store it in the arg array */
arg_array[arg_count++] = (char *)arg;
continue;
}
if (i >= argc) {
Jim_SetResultFormatted(interp, "can't specify \"%s\" as last word in command", arg);
Jim_Free(arg_array);
return -1;
}
}
if (arg_count == 0) {
Jim_SetResultString(interp, "didn't specify command to execute", -1);
Jim_Free(arg_array);
return -1;
}
/*
* Set up the redirected input source for the pipeline, if
* so requested.
*/
if (input != NULL) {
if (inputFile == FILE_TEXT) {
/*
* Immediate data in command. Create temporary file and
* put data into file.
*/
#define TMP_STDIN_NAME "/tmp/tcl.in.XXXXXX"
char inName[sizeof(TMP_STDIN_NAME) + 1];
int length;
strcpy(inName, TMP_STDIN_NAME);
inputId = mkstemp(inName);
if (inputId < 0) {
Jim_SetResultErrno(interp, "couldn't create input file for command");
goto error;
}
length = strlen(input);
if (write(inputId, input, length) != length) {
Jim_SetResultErrno(interp, "couldn't write file input for command");
goto error;
}
if (lseek(inputId, 0L, SEEK_SET) == -1 || unlink(inName) == -1) {
Jim_SetResultErrno(interp, "couldn't reset or remove input file for command");
goto error;
}
}
else if (inputFile == FILE_HANDLE) {
/* Should be a file descriptor */
Jim_Obj *fhObj = Jim_NewStringObj(interp, input, -1);
FILE *fh = Jim_AioFilehandle(interp, fhObj);
Jim_FreeNewObj(interp, fhObj);
if (fh == NULL) {
goto error;
}
inputId = dup(fileno(fh));
}
else {
/*
* File redirection. Just open the file.
*/
inputId = open(input, O_RDONLY, 0);
if (inputId < 0) {
Jim_SetResultFormatted(interp, "couldn't read file \"%s\": %s", input, strerror(errno));
goto error;
}
}
}
else if (inPipePtr != NULL) {
if (pipe(pipeIds) != 0) {
Jim_SetResultErrno(interp, "couldn't create input pipe for command");
goto error;
}
inputId = pipeIds[0];
*inPipePtr = pipeIds[1];
pipeIds[0] = pipeIds[1] = -1;
}
/*
* Set up the redirected output sink for the pipeline from one
* of two places, if requested.
*/
if (output != NULL) {
if (outputFile == FILE_HANDLE) {
Jim_Obj *fhObj = Jim_NewStringObj(interp, output, -1);
FILE *fh = Jim_AioFilehandle(interp, fhObj);
Jim_FreeNewObj(interp, fhObj);
if (fh == NULL) {
goto error;
}
fflush(fh);
lastOutputId = dup(fileno(fh));
}
else {
/*
* Output is to go to a file.
*/
int mode = O_WRONLY|O_CREAT|O_TRUNC;
if (outputFile == FILE_APPEND) {
mode = O_WRONLY|O_CREAT|O_APPEND;
}
lastOutputId = open(output, mode, 0666);
if (lastOutputId < 0) {
Jim_SetResultFormatted(interp, "couldn't write file \"%s\": %s", output, strerror(errno));
goto error;
}
}
}
else if (outPipePtr != NULL) {
/*
* Output is to go to a pipe.
*/
if (pipe(pipeIds) != 0) {
Jim_SetResultErrno(interp, "couldn't create output pipe");
goto error;
}
lastOutputId = pipeIds[1];
*outPipePtr = pipeIds[0];
pipeIds[0] = pipeIds[1] = -1;
}
/* If we are redirecting stderr with 2>filename or 2>@fileId, then we ignore errFilePtr */
if (error != NULL) {
if (errorFile == FILE_HANDLE) {
if (strcmp(error, "1") == 0) {
/* Special 2>@1 */
if (lastOutputId >= 0) {
errorId = dup(lastOutputId);
}
else {
/* No redirection stdout, so just use 2>@stdout */
error = "stdout";
}
}
if (errorId < 0) {
Jim_Obj *fhObj = Jim_NewStringObj(interp, error, -1);
FILE *fh = Jim_AioFilehandle(interp, fhObj);
Jim_FreeNewObj(interp, fhObj);
if (fh == NULL) {
goto error;
}
fflush(fh);
errorId = dup(fileno(fh));
}
}
else {
/*
* Output is to go to a file.
*/
int mode = O_WRONLY|O_CREAT|O_TRUNC;
if (errorFile == FILE_APPEND) {
mode = O_WRONLY|O_CREAT|O_APPEND;
}
errorId = open(error, mode, 0666);
if (errorId < 0) {
Jim_SetResultFormatted(interp, "couldn't write file \"%s\": %s", error, strerror(errno));
}
}
}
else if (errFilePtr != NULL) {
/*
* 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.
*/
#define TMP_STDERR_NAME "/tmp/tcl.err.XXXXXX"
char errName[sizeof(TMP_STDERR_NAME) + 1];
strcpy(errName, TMP_STDERR_NAME);
errorId = mkstemp(errName);
if (errorId < 0) {
errFileError:
Jim_SetResultErrno(interp, "couldn't create error file for command");
goto error;
}
*errFilePtr = open(errName, O_RDONLY, 0);
if (*errFilePtr < 0) {
goto errFileError;
}
if (unlink(errName) == -1) {
Jim_SetResultErrno(interp, "couldn't remove error file for command");
goto error;
}
}
/*
* Scan through the argc array, forking off a process for each
* group of arguments between "|" arguments.
*/
pidPtr = (int *)Jim_Alloc(cmdCount * sizeof(*pidPtr));
for (i = 0; i < numPids; i++) {
pidPtr[i] = -1;
}
for (firstArg = 0; firstArg < arg_count; numPids++, firstArg = lastArg+1) {
int pipe_dup_err = 0;
for (lastArg = firstArg; lastArg < arg_count; lastArg++) {
if (arg_array[lastArg][0] == '|') {
if (arg_array[lastArg][1] == '&') {
pipe_dup_err = 1;
}
break;
}
}
/* Replace | with NULL for execv() */
arg_array[lastArg] = NULL;
if (lastArg == arg_count) {
outputId = lastOutputId;
}
else {
if (pipe(pipeIds) != 0) {
Jim_SetResultErrno(interp, "couldn't create pipe");
goto error;
}
outputId = pipeIds[1];
}
execName = arg_array[firstArg];
pid = JimFork();
if (pid == -1) {
Jim_SetResultErrno(interp, "couldn't fork child process");
goto error;
}
if (pid == 0) {
char errSpace[200];
int rc;
if (pipe_dup_err) {
errorId = outputId;
}
if ((inputId != -1 && dup2(inputId, 0) == -1)
|| (outputId != -1 && dup2(outputId, 1) == -1)
|| (errorId != -1 &&(dup2(errorId, 2) == -1))) {
static const char err[] = "forked process couldn't set up input/output\n";
rc = write(errorId < 0 ? 2 : errorId, err, strlen(err));
_exit(1);
}
for (i = 3; (i <= outputId) || (i <= inputId) || (i <= errorId); i++) {
close(i);
}
execvp(execName, &arg_array[firstArg]);
sprintf(errSpace, "couldn't find \"%.150s\" to execute\n", arg_array[firstArg]);
rc = write(2, errSpace, strlen(errSpace));
_exit(1);
}
else {
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) {
close(inputId);
}
if (outputId != -1) {
close(outputId);
}
inputId = pipeIds[0];
pipeIds[0] = pipeIds[1] = -1;
}
*pidArrayPtr = pidPtr;
/*
* All done. Cleanup open files lying around and then return.
*/
cleanup:
if (inputId != -1) {
close(inputId);
}
if (lastOutputId != -1) {
close(lastOutputId);
}
if (errorId != -1) {
close(errorId);
}
Jim_Free(arg_array);
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) {
JimDetachPids(interp, 1, &pidPtr[i]);
}
}
Jim_Free(pidPtr);
}
numPids = -1;
goto cleanup;
}
/*
*----------------------------------------------------------------------
*
* CleanupChildren --
*
* This is a utility procedure used to wait for child processes
* to exit, record information about abnormal exits, and then
* collect any stderr output generated by them.
*
* Results:
* The return value is a standard Tcl result. If anything at
* weird happened with the child processes, JIM_ERROR is returned
* and a message is left in interp->result.
*
* Side effects:
* If the last character of interp->result is a newline, then it
* is removed. File errorId gets closed, and pidPtr is freed
* back to the storage allocator.
*
*----------------------------------------------------------------------
*/
static int
Jim_CleanupChildren(Jim_Interp *interp, int numPids, int *pidPtr, int errorId)
{
int result = JIM_OK;
int i;
for (i = 0; i < numPids; i++) {
int waitStatus = 0;
int pid = JimWaitPids(1, &pidPtr[i], &waitStatus);
if (pid >= 0 && JimCheckWaitStatus(interp, pid, waitStatus) != JIM_OK) {
result = JIM_ERR;
}
}
Jim_Free(pidPtr);
/*
* Read the standard error file. If there's anything there,
* then add the file's contents to the result
* string.
*/
if (errorId >= 0) {
if (JimAppendStreamToString(interp, errorId, Jim_GetResult(interp)) != JIM_OK) {
Jim_SetResultErrno(interp, "error reading from stderr output file");
result = JIM_ERR;
}
close(errorId);
}
JimTrimTrailingNewline(interp);
return result;
}
#else
static int
Jim_ExecCmd(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
int pid;
int tmpfd;
int status;
int result;
char **nargv;
int i;
#define TMP_NAME "/tmp/tcl.exec.XXXXXX"
char tmpname[sizeof(TMP_NAME) + 1];
/* Create a temporary file for the output from our exec command */
strcpy(tmpname, TMP_NAME);
tmpfd = mkstemp(tmpname);
if (tmpfd < 0) {
Jim_SetResultErrno(interp, "couldn't create temp file file for exec");
return JIM_ERR;
}
nargv = Jim_Alloc(sizeof(*nargv) * argc);
for (i = 1; i < argc; i++) {
nargv[i - 1] = (char *)Jim_GetString(argv[i], NULL);
}
nargv[i - 1] = NULL;
/*printf("Writing output to %s, fd=%d\n", tmpname, tmpfd);*/
unlink(tmpname);
/* Use vfork and send output to this temporary file */
pid = vfork();
//pid = 0;
if (pid == 0) {
close(0);
open("/dev/null", O_RDONLY);
close(1);
if (dup(tmpfd) != -1) {
close(2);
if (dup(tmpfd) != -1) {
close(tmpfd);
execvp(nargv[0], nargv);
}
}
_exit(127);
}
/* Wait for the child to exit */
waitpid(pid, &status, 0);
Jim_Free(nargv);
result = JimCheckWaitStatus(interp, pid, status);
/*
* Read the child's output (if any) and put it into the result.
*/
lseek(tmpfd, 0L, SEEK_SET);
Jim_SetResultString(interp, "", 0);
if (JimAppendStreamToString(interp, tmpfd, Jim_GetResult(interp)) != JIM_OK) {
Jim_SetResultErrno(interp, "error reading from stderr output file");
result = JIM_ERR;
}
close(tmpfd);
JimTrimTrailingNewline(interp);
return result;
}
#endif
int Jim_execInit(Jim_Interp *interp)
{
if (Jim_PackageProvide(interp, "exec", "1.0", JIM_ERRMSG) != JIM_OK) {
return JIM_ERR;
}
Jim_CreateCommand(interp, "exec", Jim_ExecCmd, NULL, NULL);
return JIM_OK;
}
|