| /******************************************************************************* |
| * Copyright (c) 2002 - 2005 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 |
| *******************************************************************************/ |
| #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++); |
| } |
| |
| 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 || waitpid(pid, &status, 0) < 0) |
| return -1; |
| |
| if (WIFEXITED(status)) { |
| val = WEXITSTATUS(status); |
| } |
| |
| return val; |
| } |