diff options
| -rw-r--r-- | init/init.c | 282 |
1 files changed, 139 insertions, 143 deletions
diff --git a/init/init.c b/init/init.c index bc8979859..e1ad1e615 100644 --- a/init/init.c +++ b/init/init.c @@ -316,7 +316,7 @@ static void open_stdio_to_tty(const char* tty_name, int fail) close(0); if ((device_open(tty_name, O_RDWR)) < 0) { dup2(1, 0); /* restore fd #0 - avoid nasty surprises */ - message(L_LOG | L_CONSOLE, "can't open %s: %s", + message(L_LOG | L_CONSOLE, "Can't open %s: %s", tty_name, strerror(errno)); if (fail) _exit(1); @@ -342,178 +342,174 @@ static pid_t run(const struct init_action *a) char *cmd[INIT_BUFFS_SIZE]; char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */ sigset_t nmask, omask; - static const char press_enter[] = -#ifdef CUSTOMIZED_BANNER -#include CUSTOMIZED_BANNER -#endif - "\nPlease press Enter to activate this console. "; /* Block sigchild while forking. */ sigemptyset(&nmask); sigaddset(&nmask, SIGCHLD); sigprocmask(SIG_BLOCK, &nmask, &omask); + pid = fork(); + sigprocmask(SIG_SETMASK, &omask, NULL); - if ((pid = fork()) == 0) { - /* Clean up */ - sigprocmask(SIG_SETMASK, &omask, NULL); - - /* Reset signal handlers that were set by the parent process */ - signal(SIGUSR1, SIG_DFL); - signal(SIGUSR2, SIG_DFL); - signal(SIGINT, SIG_DFL); - signal(SIGTERM, SIG_DFL); - signal(SIGHUP, SIG_DFL); - signal(SIGQUIT, SIG_DFL); - signal(SIGCONT, SIG_DFL); - signal(SIGSTOP, SIG_DFL); - signal(SIGTSTP, SIG_DFL); - - /* Create a new session and make ourself the process - * group leader */ - setsid(); + if (pid) + return pid; + + /* Reset signal handlers that were set by the parent process */ + signal(SIGUSR1, SIG_DFL); + signal(SIGUSR2, SIG_DFL); + signal(SIGINT, SIG_DFL); + signal(SIGTERM, SIG_DFL); + signal(SIGHUP, SIG_DFL); + signal(SIGQUIT, SIG_DFL); + signal(SIGCONT, SIG_DFL); + signal(SIGSTOP, SIG_DFL); + signal(SIGTSTP, SIG_DFL); + + /* Create a new session and make ourself the process + * group leader */ + setsid(); - /* Open the new terminal device */ - open_stdio_to_tty(a->terminal, 1); + /* Open the new terminal device */ + open_stdio_to_tty(a->terminal, 1); - /* If the init Action requires us to wait, then force the - * supplied terminal to be the controlling tty. */ - if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) { + /* If the init Action requires us to wait, then force the + * supplied terminal to be the controlling tty. */ + if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) { - /* Now fork off another process to just hang around */ - if ((pid = fork()) < 0) { - message(L_LOG | L_CONSOLE, "can't fork"); - _exit(1); - } + /* Now fork off another process to just hang around */ + if ((pid = fork()) < 0) { + message(L_LOG | L_CONSOLE, "Can't fork"); + _exit(1); + } - if (pid > 0) { + if (pid > 0) { - /* We are the parent -- wait till the child is done */ - signal(SIGINT, SIG_IGN); - signal(SIGTSTP, SIG_IGN); - signal(SIGQUIT, SIG_IGN); - signal(SIGCHLD, SIG_DFL); + /* We are the parent -- wait till the child is done */ + signal(SIGINT, SIG_IGN); + signal(SIGTSTP, SIG_IGN); + signal(SIGQUIT, SIG_IGN); + signal(SIGCHLD, SIG_DFL); - waitfor(NULL, pid); - /* See if stealing the controlling tty back is necessary */ - if (tcgetpgrp(0) != getpid()) - _exit(0); + waitfor(NULL, pid); + /* See if stealing the controlling tty back is necessary */ + if (tcgetpgrp(0) != getpid()) + _exit(0); - /* Use a temporary process to steal the controlling tty. */ - if ((pid = fork()) < 0) { - message(L_LOG | L_CONSOLE, "can't fork"); - _exit(1); - } - if (pid == 0) { - setsid(); - ioctl(0, TIOCSCTTY, 1); - _exit(0); - } - waitfor(NULL, pid); + /* Use a temporary process to steal the controlling tty. */ + if ((pid = fork()) < 0) { + message(L_LOG | L_CONSOLE, "Can't fork"); + _exit(1); + } + if (pid == 0) { + setsid(); + ioctl(0, TIOCSCTTY, 1); _exit(0); } - - /* Now fall though to actually execute things */ + waitfor(NULL, pid); + _exit(0); } - /* See if any special /bin/sh requiring characters are present */ - if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) { - cmd[0] = (char *)DEFAULT_SHELL; - cmd[1] = (char*)"-c"; - cmd[2] = strcat(strcpy(buf, "exec "), a->command); - cmd[3] = NULL; - } else { - /* Convert command (char*) into cmd (char**, one word per string) */ - strcpy(buf, a->command); - s = buf; - for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) { - if (*tmpCmd != '\0') { - cmd[i] = tmpCmd; - i++; - } + /* Now fall though to actually execute things */ + } + + /* See if any special /bin/sh requiring characters are present */ + if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) { + cmd[0] = (char*)DEFAULT_SHELL; + cmd[1] = (char*)"-c"; + cmd[2] = strcat(strcpy(buf, "exec "), a->command); + cmd[3] = NULL; + } else { + /* Convert command (char*) into cmd (char**, one word per string) */ + strcpy(buf, a->command); + s = buf; + for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) { + if (*tmpCmd != '\0') { + cmd[i] = tmpCmd; + i++; } - cmd[i] = NULL; } + cmd[i] = NULL; + } - cmdpath = cmd[0]; - - /* - * Interactive shells want to see a dash in argv[0]. This - * typically is handled by login, argv will be setup this - * way if a dash appears at the front of the command path - * (like "-/bin/sh"). - */ - if (*cmdpath == '-') { - /* skip over the dash */ - ++cmdpath; - - /* find the last component in the command pathname */ - s = bb_get_last_path_component(cmdpath); - - /* make a new argv[0] */ - if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) { - message(L_LOG | L_CONSOLE, bb_msg_memory_exhausted); - cmd[0] = cmdpath; - } else { - cmd[0][0] = '-'; - strcpy(cmd[0] + 1, s); - } + cmdpath = cmd[0]; + + /* + * Interactive shells want to see a dash in argv[0]. This + * typically is handled by login, argv will be setup this + * way if a dash appears at the front of the command path + * (like "-/bin/sh"). + */ + if (*cmdpath == '-') { + /* skip over the dash */ + ++cmdpath; + + /* find the last component in the command pathname */ + s = bb_get_last_path_component(cmdpath); + + /* make a new argv[0] */ + if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) { + message(L_LOG | L_CONSOLE, bb_msg_memory_exhausted); + cmd[0] = cmdpath; + } else { + cmd[0][0] = '-'; + strcpy(cmd[0] + 1, s); + } #if ENABLE_FEATURE_INIT_SCTTY - /* Establish this process as session leader and - * (attempt) to make the tty (if any) a controlling tty. - */ - setsid(); - ioctl(0, TIOCSCTTY, 0 /*don't steal it*/); + /* Establish this process as session leader and + * (attempt) to make the tty (if any) a controlling tty. + */ + setsid(); + ioctl(0, TIOCSCTTY, 0 /*don't steal it*/); #endif - } + } #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__) - if (a->action & ASKFIRST) { - char c; - /* - * Save memory by not exec-ing anything large (like a shell) - * before the user wants it. This is critical if swap is not - * enabled and the system has low memory. Generally this will - * be run on the second virtual console, and the first will - * be allowed to start a shell or whatever an init script - * specifies. - */ - messageD(L_LOG, "Waiting for enter to start '%s'" - "(pid %d, tty '%s')\n", - cmdpath, getpid(), a->terminal); - full_write(1, press_enter, sizeof(press_enter) - 1); - while (read(0, &c, 1) == 1 && c != '\n') - ; - } + if (a->action & ASKFIRST) { + static const char press_enter[] = +#ifdef CUSTOMIZED_BANNER +#include CUSTOMIZED_BANNER #endif - - /* Log the process name and args */ - message(L_LOG, "starting pid %d, tty '%s': '%s'", - getpid(), a->terminal, cmdpath); + "\nPlease press Enter to activate this console. "; + char c; + /* + * Save memory by not exec-ing anything large (like a shell) + * before the user wants it. This is critical if swap is not + * enabled and the system has low memory. Generally this will + * be run on the second virtual console, and the first will + * be allowed to start a shell or whatever an init script + * specifies. + */ + messageD(L_LOG, "waiting for enter to start '%s'" + "(pid %d, tty '%s')\n", + cmdpath, getpid(), a->terminal); + full_write(1, press_enter, sizeof(press_enter) - 1); + while (read(0, &c, 1) == 1 && c != '\n') + ; + } +#endif + /* Log the process name and args */ + message(L_LOG, "starting pid %d, tty '%s': '%s'", + getpid(), a->terminal, cmdpath); #if ENABLE_FEATURE_INIT_COREDUMPS - { - struct stat sb; - if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) { - struct rlimit limit; + { + struct stat sb; + if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) { + struct rlimit limit; - limit.rlim_cur = RLIM_INFINITY; - limit.rlim_max = RLIM_INFINITY; - setrlimit(RLIMIT_CORE, &limit); - } + limit.rlim_cur = RLIM_INFINITY; + limit.rlim_max = RLIM_INFINITY; + setrlimit(RLIMIT_CORE, &limit); } -#endif - - /* Now run it. The new program will take over this PID, - * so nothing further in init.c should be run. */ - BB_EXECVP(cmdpath, cmd); - - /* We're still here? Some error happened. */ - message(L_LOG | L_CONSOLE, "Cannot run '%s': %s", - cmdpath, strerror(errno)); - _exit(-1); } - sigprocmask(SIG_SETMASK, &omask, NULL); - return pid; +#endif + /* Now run it. The new program will take over this PID, + * so nothing further in init.c should be run. */ + BB_EXECVP(cmdpath, cmd); + + /* We're still here? Some error happened. */ + message(L_LOG | L_CONSOLE, "Cannot run '%s': %s", + cmdpath, strerror(errno)); + _exit(-1); } static int waitfor(const struct init_action *a, pid_t pid) |