| /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * |
| * COPYING NOTES |
| * |
| * timeout.c -- a timeout handler for shell commands |
| * |
| * Copyright (C) 2005-6, Roberto A. Foglietta <me@roberto.foglietta.name> |
| * |
| * 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; version 2 of the License. |
| * |
| * This program is distributed in the hope that it will 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 to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. |
| */ |
| /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * |
| * REVISION NOTES: |
| * released 17-11-2005 by Roberto A. Foglietta |
| * talarm 04-12-2005 by Roberto A. Foglietta |
| * modified 05-12-2005 by Roberto A. Foglietta |
| * sizerdct 06-12-2005 by Roberto A. Foglietta |
| * splitszf 12-05-2006 by Roberto A. Foglietta |
| * rewrite 14-11-2008 vda |
| */ |
| |
| #include "libbb.h" |
| |
| int timeout_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int timeout_main(int argc UNUSED_PARAM, char **argv) |
| { |
| int signo; |
| int status; |
| int parent = 0; |
| int timeout = 10; |
| pid_t pid; |
| #if !BB_MMU |
| char *sv1, *sv2; |
| #endif |
| const char *opt_s = "TERM"; |
| |
| /* -p option is not documented, it is needed to support NOMMU. */ |
| |
| /* -t SECONDS; -p PARENT_PID */ |
| opt_complementary = "t+" USE_FOR_NOMMU(":p+"); |
| /* '+': stop at first non-option */ |
| getopt32(argv, "+s:t:" USE_FOR_NOMMU("p:"), &opt_s, &timeout, &parent); |
| /*argv += optind; - no, wait for bb_daemonize_or_rexec! */ |
| signo = get_signum(opt_s); |
| if (signo < 0) |
| bb_error_msg_and_die("unknown signal '%s'", opt_s); |
| |
| /* We want to create a grandchild which will watch |
| * and kill the grandparent. Other methods: |
| * making parent watch child disrupts parent<->child link |
| * (example: "tcpsvd 0.0.0.0 1234 timeout service_prog" - |
| * it's better if service_prog is a child of tcpsvd!), |
| * making child watch parent results in programs having |
| * unexpected children. */ |
| |
| if (parent) /* we were re-execed, already grandchild */ |
| goto grandchild; |
| if (!argv[optind]) /* no PROG? */ |
| bb_show_usage(); |
| |
| #if !BB_MMU |
| sv1 = argv[optind]; |
| sv2 = argv[optind + 1]; |
| #endif |
| pid = vfork(); |
| if (pid < 0) |
| bb_perror_msg_and_die("vfork"); |
| if (pid == 0) { |
| /* Child: spawn grandchild and exit */ |
| parent = getppid(); |
| #if !BB_MMU |
| argv[optind] = xasprintf("-p%u", parent); |
| argv[optind + 1] = NULL; |
| #endif |
| /* NB: exits with nonzero on error: */ |
| bb_daemonize_or_rexec(0, argv); |
| /* Here we are grandchild. Sleep, then kill grandparent */ |
| grandchild: |
| /* Just sleep(NUGE_NUM); kill(parent) may kill wrong process! */ |
| while (1) { |
| sleep(1); |
| if (--timeout <= 0) |
| break; |
| if (kill(parent, 0)) { |
| /* process is gone */ |
| return EXIT_SUCCESS; |
| } |
| } |
| kill(parent, signo); |
| return EXIT_SUCCESS; |
| } |
| |
| /* Parent */ |
| wait(&status); /* wait for child to die */ |
| /* Did intermediate [v]fork or exec fail? */ |
| if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) |
| return EXIT_FAILURE; |
| /* Ok, exec a program as requested */ |
| argv += optind; |
| #if !BB_MMU |
| argv[0] = sv1; |
| argv[1] = sv2; |
| #endif |
| BB_EXECVP(argv[0], argv); |
| bb_perror_msg_and_die("can't execute '%s'", argv[0]); |
| } |