| /* |
| * Copyright (c) 2016 Cyril Hrubis <chrubis@suse.cz> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation; either version 2 of |
| * the License, or (at your option) any later version. |
| * |
| * This program is distributed in the hope that it would be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <errno.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <fcntl.h> |
| |
| #define WRITE_STRING(fd, string) if (write(fd, string, sizeof(string)-1)) {} |
| |
| int main(int argc, char *argv[]) |
| { |
| int i, pos = 0; |
| char *args[argc]; |
| char *stdin_path = NULL, *stdout_path = NULL, *stderr_path = NULL; |
| int stderr_fd = 0; |
| |
| if (argc <= 1) { |
| fprintf(stderr, "%s: Takes at least one agrument!\n", argv[0]); |
| return 1; |
| } |
| |
| for (i = 1; i < argc; i++) { |
| |
| if (argv[i][0] == '>') { |
| if (argv[i][1]) { |
| stdout_path = argv[i]+1; |
| } else { |
| if (++i >= argc) { |
| fprintf(stderr, |
| "%s: Missing filename after >\n", |
| argv[0]); |
| return 1; |
| } |
| stdout_path = argv[i]; |
| } |
| continue; |
| } |
| |
| if (argv[i][0] == '<') { |
| if (argv[i][1]) { |
| stdin_path = argv[i]+1; |
| } else { |
| if (++i >= argc) { |
| fprintf(stderr, |
| "%s: Missing filename after <\n", |
| argv[0]); |
| return 1; |
| } |
| stdin_path = argv[i]; |
| } |
| continue; |
| } |
| |
| if (argv[i][0] == '2' && argv[i][1] == '>') { |
| if (argv[i][2]) { |
| stderr_path = argv[i]+2; |
| } else { |
| if (++i >= argc) { |
| fprintf(stderr, |
| "%s: Missing filename after 2>\n", |
| argv[0]); |
| return 1; |
| } |
| stderr_path = argv[i]; |
| } |
| continue; |
| } |
| |
| args[pos++] = argv[i]; |
| } |
| |
| args[pos] = NULL; |
| |
| if (stdin_path) { |
| if (close(0)) { |
| fprintf(stderr, "%s: Failed to close stdin: %s\n", |
| argv[0], strerror(errno)); |
| return 1; |
| } |
| if (open(stdin_path, O_RDONLY) < 0) { |
| fprintf(stderr, |
| "%s: Failed to open '%s' for reading: %s\n", |
| argv[0], stdin_path, strerror(errno)); |
| return 1; |
| } |
| } |
| |
| if (stdout_path) { |
| if (close(1)) { |
| fprintf(stderr, "%s: Failed to close stdout: %s\n", |
| argv[0], strerror(errno)); |
| return 1; |
| } |
| if (open(stdout_path, O_CREAT|O_WRONLY|O_TRUNC, 0777) < 0) { |
| fprintf(stderr, |
| "%s: Failed to open '%s' for writing: %s\n", |
| argv[0], stdin_path, strerror(errno)); |
| return 1; |
| } |
| } |
| |
| if (stderr_path) { |
| int fd = open(stderr_path, O_CREAT|O_WRONLY|O_TRUNC, 0777); |
| int stderr_fd = dup(2); |
| |
| if (stderr_fd < 0) { |
| fprintf(stderr, "%s: Failed to dup() stderr: %s\n", |
| argv[0], strerror(errno)); |
| return 1; |
| } |
| |
| if (fd < 0) { |
| fprintf(stderr, |
| "%s: Failed to open '%s' for writing: %s\n", |
| argv[0], stdin_path, strerror(errno)); |
| return 1; |
| } |
| |
| if (dup2(fd, 2) < 0) { |
| fprintf(stderr, "%s: Failed to dup2 stderr: %s\n", |
| argv[0], strerror(errno)); |
| WRITE_STRING(stderr_fd, "Failed to dup2 stderr\n"); |
| return 1; |
| } |
| } |
| |
| execvp(argv[1], args); |
| |
| /* Fall back to shell if command wasn't found */ |
| FILE *sin = popen("/bin/sh", "w"); |
| |
| if (!sin) { |
| if (stderr_fd) { |
| WRITE_STRING(stderr_fd, "Failed to popen /bin/sh\n"); |
| } else { |
| fprintf(stderr, "%s: Failed to popen /bin/sh: %s\n", |
| argv[0], strerror(errno)); |
| } |
| return 1; |
| } |
| |
| //TODO: Should we escape args? |
| for (i = 0; args[i]; i++) |
| fprintf(sin, "%s ", args[i]); |
| |
| return pclose(sin); |
| } |