/******************************************************************************* | |
* Copyright (c) 2002, 2010 QNX Software Systems and others. | |
* All rights reserved. This program and the accompanying materials | |
* are made available under the terms of the Eclipse Public License v1.0 | |
* which accompanies this distribution, and is available at | |
* http://www.eclipse.org/legal/epl-v10.html | |
* | |
* Contributors: | |
* QNX Software Systems - initial API and implementation | |
* Wind River Systems, Inc. | |
* Mikhail Sennikovsky - bug 145737 | |
*******************************************************************************/ | |
#include "exec0.h" | |
#include <unistd.h> | |
#include <stdlib.h> | |
#include <stdio.h> | |
#include <errno.h> | |
#include <string.h> | |
#include <libgen.h> | |
#include <stdlib.h> | |
/* from pfind.c */ | |
extern char *pfind(const char *name, char * const envp[]); | |
pid_t | |
exec0(const char *path, char *const argv[], char *const envp[], | |
const char *dirpath, int channels[3]) | |
{ | |
int pipe0[2], pipe1[2], pipe2[2]; | |
pid_t childpid; | |
char *full_path; | |
/* | |
* We use pfind() to check that the program exists and is an executable. | |
* If not pass the error up. Also execve() wants a full path. | |
*/ | |
full_path = pfind(path, envp); | |
if (full_path == NULL) { | |
fprintf(stderr, "Unable to find full path for \"%s\"\n", (path) ? path : ""); | |
return -1; | |
} | |
/* | |
* Make sure we can create our pipes before forking. | |
*/ | |
if (channels != NULL) { | |
if (pipe(pipe0) < 0 || pipe(pipe1) < 0 || pipe(pipe2) < 0) { | |
fprintf(stderr, "%s(%d): returning due to error.\n", | |
__FUNCTION__, __LINE__); | |
free(full_path); | |
return -1; | |
} | |
} | |
childpid = fork(); | |
if (childpid < 0) { | |
fprintf(stderr, "%s(%d): returning due to error: %s\n", | |
__FUNCTION__, __LINE__, strerror(errno)); | |
free(full_path); | |
return -1; | |
} else if (childpid == 0) { /* child */ | |
char *ptr; | |
chdir(dirpath); | |
if (channels != NULL) { | |
/* Close the write end of pipe0 */ | |
if (close(pipe0[1]) == -1) | |
perror("close(pipe0[1])"); | |
/* Close the read end of pipe1 */ | |
if (close(pipe1[0]) == -1) | |
perror("close(pipe1[0])"); | |
/* Close the read end of pipe2 */ | |
if (close(pipe2[0]) == -1) | |
perror("close(pipe2[0]))"); | |
/* redirections */ | |
dup2(pipe0[0], STDIN_FILENO); /* dup stdin */ | |
dup2(pipe1[1], STDOUT_FILENO); /* dup stdout */ | |
dup2(pipe2[1], STDERR_FILENO); /* dup stderr */ | |
} | |
/* Close all the fd's in the child */ | |
{ | |
int fdlimit = sysconf(_SC_OPEN_MAX); | |
int fd = 3; | |
while (fd < fdlimit) | |
close(fd++); | |
} | |
setpgid(getpid(), getpid()); | |
if (envp[0] == NULL) { | |
execv(full_path, argv); | |
} else { | |
execve(full_path, argv, envp); | |
} | |
_exit(127); | |
} else if (childpid != 0) { /* parent */ | |
char b; | |
if (channels != NULL) { | |
/* close the read end of pipe1 */ | |
if (close(pipe0[0]) == -1) | |
perror("close(pipe0[0])"); | |
/* close the write end of pipe2 */ | |
if (close(pipe1[1]) == -1) | |
perror("close(pipe1[1])"); | |
/* close the write end of pipe2 */ | |
if (close(pipe2[1]) == -1) | |
perror("close(pipe2[1])"); | |
channels[0] = pipe0[1]; /* Output Stream. */ | |
channels[1] = pipe1[0]; /* Input Stream. */ | |
channels[2] = pipe2[0]; /* Input Stream. */ | |
} | |
free(full_path); | |
return childpid; | |
} | |
free(full_path); | |
return -1; /*NOT REACHED */ | |
} | |
int wait0(pid_t pid) | |
{ | |
int status; | |
int val = -1; | |
if (pid < 0) | |
return -1; | |
for (;;) { | |
if (waitpid(pid, &status, 0) < 0) { | |
if (errno == EINTR) { | |
// interrupted system call - retry | |
continue; | |
} | |
} | |
break; | |
} | |
if (WIFEXITED(status)) { | |
val = WEXITSTATUS(status); | |
} | |
return val; | |
} |