X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=main.c;h=622ba631519b90811d92e8aae79d9c15acf5514f;hp=c2f1ef856d5703769688c457522ba2d2282f6dda;hb=c99b188ea0f6c4b0c63aa56c439df9bab16b7924;hpb=a5dab5ce0fd4aafc394afe30eda0e6b01a13256b diff --git a/main.c b/main.c index c2f1ef856..622ba6315 100644 --- a/main.c +++ b/main.c @@ -28,19 +28,172 @@ #include #include #include +#include +#include +#include #include "manager.h" #include "log.h" #include "mount-setup.h" +#include "hostname-setup.h" +#include "load-fragment.h" static enum { ACTION_RUN, - ACTION_HELP + ACTION_HELP, + ACTION_TEST, + ACTION_DUMP_CONFIGURATION_ITEMS } action = ACTION_RUN; static char *default_unit = NULL; static ManagerRunningAs running_as = _MANAGER_RUNNING_AS_INVALID; +static bool dump_core = true; +static bool crash_shell = false; +static int crash_chvt = -1; + +static bool confirm_spawn = false; + +_noreturn static void freeze(void) { + for (;;) + pause(); +} + +_noreturn static void crash(int sig) { + + if (!dump_core) + log_error("Caught <%s>, not dumping core.", strsignal(sig)); + else { + pid_t pid; + + if ((pid = fork()) < 0) + log_error("Caught <%s>, cannot fork for core dump: %s", strsignal(sig), strerror(errno)); + + else if (pid == 0) { + struct sigaction sa; + struct rlimit rl; + + /* Enable default signal handler for core dump */ + zero(sa); + sa.sa_handler = SIG_DFL; + assert_se(sigaction(sig, &sa, NULL) == 0); + + /* Don't limit the core dump size */ + zero(rl); + rl.rlim_cur = RLIM_INFINITY; + rl.rlim_max = RLIM_INFINITY; + setrlimit(RLIMIT_CORE, &rl); + + /* Just to be sure... */ + assert_se(chdir("/") == 0); + + /* Raise the signal again */ + raise(sig); + + assert_not_reached("We shouldn't be here..."); + _exit(1); + + } else { + int status, r; + + /* Order things nicely. */ + if ((r = waitpid(pid, &status, 0)) < 0) + log_error("Caught <%s>, waitpid() failed: %s", strsignal(sig), strerror(errno)); + else if (!WCOREDUMP(status)) + log_error("Caught <%s>, core dump failed.", strsignal(sig)); + else + log_error("Caught <%s>, dumped core as pid %llu.", strsignal(sig), (unsigned long long) pid); + } + } + + if (crash_chvt) + chvt(crash_chvt); + + if (crash_shell) { + sigset_t mask; + + log_info("Executing crash shell in 10s..."); + sleep(10); + + /* Make sure the signal is not delivered inside the + * exec() */ + assert_se(sigemptyset(&mask) == 0); + assert_se(sigaddset(&mask, sig) == 0); + assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0); + + ignore_signal(sig); + + execl("/bin/sh", "/bin/sh", NULL); + log_error("execl() failed: %s", strerror(errno)); + } + + log_info("Freezing execution."); + freeze(); +} + +static void install_crash_handler(void) { + struct sigaction sa; + + zero(sa); + + sa.sa_handler = crash; + sa.sa_flags = SA_NODEFER; + + assert_se(sigaction(SIGSEGV, &sa, NULL) == 0); + assert_se(sigaction(SIGILL, &sa, NULL) == 0); + assert_se(sigaction(SIGFPE, &sa, NULL) == 0); + assert_se(sigaction(SIGBUS, &sa, NULL) == 0); + assert_se(sigaction(SIGQUIT, &sa, NULL) == 0); + assert_se(sigaction(SIGABRT, &sa, NULL) == 0); +} + +static int console_setup(void) { + int tty_fd = -1, null_fd = -1, r = 0; + + /* If we are init, we connect stdout/stderr to /dev/console + * and stdin to /dev/null and make sure we don't have a + * controlling tty. */ + + release_terminal(); + + if ((tty_fd = open_terminal("/dev/console", O_WRONLY)) < 0) { + log_error("Failed to open /dev/console: %s", strerror(-tty_fd)); + r = -tty_fd; + goto finish; + } + + if ((null_fd = open("/dev/null", O_RDONLY)) < 0) { + log_error("Failed to open /dev/null: %m"); + r = -errno; + goto finish; + } + + assert(tty_fd >= 3); + assert(null_fd >= 3); + + if (reset_terminal(tty_fd) < 0) + log_error("Failed to reset /dev/console: %m"); + + if (dup2(tty_fd, STDOUT_FILENO) < 0 || + dup2(tty_fd, STDERR_FILENO) < 0 || + dup2(null_fd, STDIN_FILENO) < 0) { + log_error("Failed to dup2() device: %m"); + r = -errno; + goto finish; + } + + r = 0; + +finish: + if (tty_fd >= 0) + close_nointr(tty_fd); + + if (null_fd >= 0) + close_nointr(null_fd); + + return r; +} + static int set_default_unit(const char *u) { char *c; @@ -69,7 +222,7 @@ static int parse_proc_cmdline_word(const char *word) { }; if (startswith(word, "systemd.default=")) - return set_default_unit(word + 15); + return set_default_unit(word + 16); else if (startswith(word, "systemd.log_target=")) { @@ -81,11 +234,46 @@ static int parse_proc_cmdline_word(const char *word) { if (log_set_max_level_from_string(word + 18) < 0) log_warning("Failed to parse log level %s. Ignoring.", word + 18); + } else if (startswith(word, "systemd.dump_core=")) { + int r; + + if ((r = parse_boolean(word + 18)) < 0) + log_warning("Failed to parse dump core switch %s, Ignoring.", word + 18); + else + dump_core = r; + + } else if (startswith(word, "systemd.crash_shell=")) { + int r; + + if ((r = parse_boolean(word + 20)) < 0) + log_warning("Failed to parse crash shell switch %s, Ignoring.", word + 20); + else + crash_shell = r; + + } else if (startswith(word, "systemd.crash_chvt=")) { + int k; + + if (safe_atoi(word + 19, &k) < 0) + log_warning("Failed to parse crash chvt switch %s, Ignoring.", word + 19); + else + crash_chvt = k; + + } else if (startswith(word, "systemd.")) { + + log_warning("Unknown kernel switch %s. Ignoring.", word); + + log_info("Supported kernel switches:"); + log_info("systemd.default=UNIT Default unit to start"); + log_info("systemd.log_target=console|kmsg|syslog Log target"); + log_info("systemd.log_level=LEVEL Log level"); + log_info("systemd.dump_core=0|1 Dump core on crash"); + log_info("systemd.crash_shell=0|1 On crash run shell"); + log_info("systemd.crash_chvt=N Change to VT #N on crash"); + } else { unsigned i; /* SysV compatibility */ - for (i = 0; i < ELEMENTSOF(rlmap); i += 2) if (streq(word, rlmap[i])) return set_default_unit(rlmap[i+1]); @@ -134,7 +322,10 @@ static int parse_argv(int argc, char *argv[]) { ARG_LOG_LEVEL = 0x100, ARG_LOG_TARGET, ARG_DEFAULT, - ARG_RUNNING_AS + ARG_RUNNING_AS, + ARG_TEST, + ARG_DUMP_CONFIGURATION_ITEMS, + ARG_CONFIRM_SPAWN }; static const struct option options[] = { @@ -142,7 +333,10 @@ static int parse_argv(int argc, char *argv[]) { { "log-target", required_argument, NULL, ARG_LOG_TARGET }, { "default", required_argument, NULL, ARG_DEFAULT }, { "running-as", required_argument, NULL, ARG_RUNNING_AS }, + { "test", no_argument, NULL, ARG_TEST }, { "help", no_argument, NULL, 'h' }, + { "dump-configuration-items", no_argument, NULL, ARG_DUMP_CONFIGURATION_ITEMS }, + { "confirm-spawn", no_argument, NULL, ARG_CONFIRM_SPAWN }, { NULL, 0, NULL, 0 } }; @@ -193,6 +387,18 @@ static int parse_argv(int argc, char *argv[]) { break; } + case ARG_TEST: + action = ACTION_TEST; + break; + + case ARG_DUMP_CONFIGURATION_ITEMS: + action = ACTION_DUMP_CONFIGURATION_ITEMS; + break; + + case ARG_CONFIRM_SPAWN: + confirm_spawn = true; + break; + case 'h': action = ACTION_HELP; break; @@ -205,22 +411,20 @@ static int parse_argv(int argc, char *argv[]) { return -EINVAL; } - if (optind < argc) { - log_error("Too many arguments."); - return -EINVAL; - } - return 0; } static int help(void) { printf("%s [options]\n\n" - " -h --help Show this help\n" - " --default=UNIT Set default unit\n" - " --log-level=LEVEL Set log level\n" - " --log-target=TARGET Set log target (console, syslog, kmsg)\n" - " --running-as=AS Set running as (init, system, sesstion)\n", + " -h --help Show this help\n" + " --default=UNIT Set default unit\n" + " --log-level=LEVEL Set log level\n" + " --log-target=TARGET Set log target (console, syslog, kmsg)\n" + " --running-as=AS Set running as (init, system, session)\n" + " --test Determine startup sequence, dump it and exit\n" + " --dump-configuration-items Dump understood unit configuration items\n" + " --confirm-spawn Ask for confirmation when spawning processes\n", __progname); return 0; @@ -244,11 +448,16 @@ int main(int argc, char *argv[]) { /* Mount /proc, /sys and friends, so that /proc/cmdline and * /proc/$PID/fd is available. */ - mount_setup(); + if (mount_setup() < 0) + goto finish; /* Reset all signal handlers. */ assert_se(reset_all_signal_handlers() == 0); + /* If we are init, we can block sigkill. Yay. */ + ignore_signal(SIGKILL); + ignore_signal(SIGPIPE); + /* Close all open files */ assert_se(close_all_fds(NULL, 0) == 0); @@ -264,29 +473,51 @@ int main(int argc, char *argv[]) { if (action == ACTION_HELP) { retval = help(); goto finish; + } else if (action == ACTION_DUMP_CONFIGURATION_ITEMS) { + unit_dump_config_items(stdout); + retval = 0; + goto finish; } - assert_se(action == ACTION_RUN); + assert_se(action == ACTION_RUN || action == ACTION_TEST); + + /* Set up PATH unless it is already set */ + setenv("PATH", + "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin", + running_as == MANAGER_INIT); /* Move out of the way, so that we won't block unmounts */ assert_se(chdir("/") == 0); - /* Become a session leader if we aren't one yet. */ - setsid(); + if (running_as != MANAGER_SESSION) { + /* Become a session leader if we aren't one yet. */ + setsid(); - /* Disable the umask logic */ - umask(0); + /* Disable the umask logic */ + umask(0); + } + + if (running_as == MANAGER_INIT) + console_setup(); /* Make sure D-Bus doesn't fiddle with the SIGPIPE handlers */ dbus_connection_set_change_sigpipe(FALSE); - /* Open the logging devices, if possible and necessary*/ + /* Open the logging devices, if possible and necessary */ log_open_syslog(); log_open_kmsg(); + /* Make sure we leave a core dump without panicing the + * kernel. */ + if (getpid() == 1) + install_crash_handler(); + log_debug("systemd running in %s mode.", manager_running_as_to_string(running_as)); - if ((r = manager_new(running_as, &m)) < 0) { + if (running_as == MANAGER_INIT) + hostname_setup(); + + if ((r = manager_new(running_as, confirm_spawn, &m)) < 0) { log_error("Failed to allocate manager object: %s", strerror(-r)); goto finish; } @@ -300,19 +531,34 @@ int main(int argc, char *argv[]) { if ((r = manager_load_unit(m, default_unit, &target)) < 0) { log_error("Failed to load default target: %s", strerror(-r)); - goto finish; + + log_info("Trying to load rescue target..."); + if ((r = manager_load_unit(m, SPECIAL_RESCUE_TARGET, &target)) < 0) { + log_error("Failed to load rescue target: %s", strerror(-r)); + goto finish; + } } - printf("→ By units:\n"); - manager_dump_units(m, stdout, "\t"); + if (action == ACTION_TEST) { + printf("→ By units:\n"); + manager_dump_units(m, stdout, "\t"); + } if ((r = manager_add_job(m, JOB_START, target, JOB_REPLACE, false, &job)) < 0) { log_error("Failed to start default target: %s", strerror(-r)); goto finish; } - printf("→ By jobs:\n"); - manager_dump_jobs(m, stdout, "\t"); + if (action == ACTION_TEST) { + printf("→ By jobs:\n"); + manager_dump_jobs(m, stdout, "\t"); + + if (getpid() == 1) + pause(); + + retval = 0; + goto finish; + } if ((r = manager_loop(m)) < 0) { log_error("Failed to run mainloop: %s", strerror(-r)); @@ -331,5 +577,8 @@ finish: dbus_shutdown(); + if (getpid() == 1) + freeze(); + return retval; }