chiark / gitweb /
utils: show help blurb when run without any arguments
[elogind.git] / src / systemctl.c
index a41d7ea8bdf8c8404fc944afc739da8590d4d191..78310aa273859a988e2bfc6bc70f1d0d70898672 100644 (file)
@@ -28,6 +28,8 @@
 #include <sys/ioctl.h>
 #include <termios.h>
 #include <unistd.h>
+#include <fcntl.h>
+#include <sys/socket.h>
 
 #include <dbus/dbus.h>
 
@@ -37,6 +39,8 @@
 #include "set.h"
 #include "utmp-wtmp.h"
 #include "special.h"
+#include "initreq.h"
+#include "strv.h"
 
 static const char *arg_type = NULL;
 static bool arg_all = false;
@@ -100,6 +104,32 @@ static int bus_iter_get_basic_and_next(DBusMessageIter *iter, int type, void *da
         return 0;
 }
 
+static int bus_check_peercred(DBusConnection *c) {
+        int fd;
+        struct ucred ucred;
+        socklen_t l;
+
+        assert(c);
+
+        assert_se(dbus_connection_get_unix_fd(c, &fd));
+
+        l = sizeof(struct ucred);
+        if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &ucred, &l) < 0) {
+                log_error("SO_PEERCRED failed: %m");
+                return -errno;
+        }
+
+        if (l != sizeof(struct ucred)) {
+                log_error("SO_PEERCRED returned wrong size.");
+                return -E2BIG;
+        }
+
+        if (ucred.uid != 0)
+                return -EPERM;
+
+        return 1;
+}
+
 static int columns(void) {
         static int parsed_columns = 0;
         const char *e;
@@ -137,6 +167,23 @@ static void warn_wall(enum action action) {
         if (arg_no_wall)
                 return;
 
+        if (arg_wall) {
+                char *p;
+
+                if (!(p = strv_join(arg_wall, " "))) {
+                        log_error("Failed to join strings.");
+                        return;
+                }
+
+                if (*p) {
+                        utmp_wall(p);
+                        free(p);
+                        return;
+                }
+
+                free(p);
+        }
+
         if (!table[action])
                 return;
 
@@ -1381,8 +1428,8 @@ finish:
 
 static int systemctl_help(void) {
 
-        printf("%s [options]\n\n"
-               "Send control commands to the init daemon.\n\n"
+        printf("%s [OPTIONS...] {COMMAND} ...\n\n"
+               "Send control commands to the systemd manager.\n\n"
                "  -h --help      Show this help\n"
                "  -t --type=TYPE List only units of a particular type\n"
                "  -a --all       Show all units, including dead ones\n"
@@ -1390,7 +1437,7 @@ static int systemctl_help(void) {
                "     --system    Connect to system bus\n"
                "     --session   Connect to session bus\n"
                "     --block     Wait until operation finished\n"
-               "     --no-wall   Don't send wall message before reboot/halt/power-off\n\n"
+               "     --no-wall   Don't send wall message before halt/power-off/reboot\n\n"
                "Commands:\n"
                "  list-units                      List units\n"
                "  list-jobs                       List jobs\n"
@@ -1405,15 +1452,15 @@ static int systemctl_help(void) {
                "  monitor                         Monitor unit/job changes\n"
                "  dump                            Dump server status\n"
                "  snapshot [NAME]                 Create a snapshot\n"
-               "  daemon-reload                   Reload init daemon configuration\n"
-               "  daemon-reexecute                Reexecute init daemon\n"
-               "  daemon-exit                     Ask the init daemon to quit\n"
+               "  daemon-reload                   Reload systemd manager configuration\n"
+               "  daemon-reexec                   Reexecute systemd manager\n"
+               "  daemon-exit                     Ask the systemd manager to quit\n"
                "  show-environment                Dump environment\n"
                "  set-environment [NAME=VALUE...] Set one or more environment variables\n"
                "  unset-environment [NAME...]     Unset one or more environment variables\n"
                "  halt                            Shut down and halt the system\n"
+               "  poweroff                        Shut down and power-off the system\n"
                "  reboot                          Shut down and reboot the system\n"
-               "  poweroff                        Shut down and power off the system\n"
                "  default                         Enter default mode\n"
                "  rescue                          Enter rescue mode\n"
                "  emergency                       Enter emergency mode\n",
@@ -1424,17 +1471,17 @@ static int systemctl_help(void) {
 
 static int halt_help(void) {
 
-        printf("%s [options]\n\n"
+        printf("%s [OPTIONS...]\n\n"
                "%s the system.\n\n"
                "     --help      Show this help\n"
                "     --halt      Halt the machine\n"
                "  -p --poweroff  Switch off the machine\n"
                "     --reboot    Reboot the machine\n"
-               "  -f --force     Force immediate reboot/halt/power-off\n"
-               "  -w --wtmp-only Don't reboot/halt/power-off, just write wtmp record\n"
+               "  -f --force     Force immediate halt/power-off/reboot\n"
+               "  -w --wtmp-only Don't halt/power-off/reboot, just write wtmp record\n"
                "  -d --no-wtmp   Don't write wtmp record\n"
-               "  -n --no-sync   Don't sync before reboot/halt/power-off\n"
-               "     --no-wall   Don't send wall message before reboot/halt/power-off\n",
+               "  -n --no-sync   Don't sync before halt/power-off/reboot\n"
+               "     --no-wall   Don't send wall message before halt/power-off/reboot\n",
                program_invocation_short_name,
                arg_action == ACTION_REBOOT   ? "Reboot" :
                arg_action == ACTION_POWEROFF ? "Power off" :
@@ -1445,15 +1492,15 @@ static int halt_help(void) {
 
 static int shutdown_help(void) {
 
-        printf("%s [options] [IGNORED] [WALL...]\n\n"
+        printf("%s [OPTIONS...] [now] [WALL...]\n\n"
                "Shut down the system.\n\n"
                "     --help      Show this help\n"
                "  -H --halt      Halt the machine\n"
                "  -P --poweroff  Power-off the machine\n"
                "  -r --reboot    Reboot the machine\n"
                "  -h             Equivalent to --poweroff, overriden by --halt\n"
-               "  -k             Don't reboot/halt/power-off, just send warnings\n"
-               "     --no-wall   Don't send wall message before reboot/halt/power-off\n",
+               "  -k             Don't halt/power-off/reboot, just send warnings\n"
+               "     --no-wall   Don't send wall message before halt/power-off/reboot\n",
                program_invocation_short_name);
 
         return 0;
@@ -1461,10 +1508,10 @@ static int shutdown_help(void) {
 
 static int telinit_help(void) {
 
-        printf("%s [options]\n\n"
+        printf("%s [OPTIONS...] {COMMAND}\n\n"
                "Send control commands to the init daemon.\n\n"
                "     --help      Show this help\n"
-               "     --no-wall   Don't send wall message before reboot/halt/power-off\n\n"
+               "     --no-wall   Don't send wall message before halt/power-off/reboot\n\n"
                "Commands:\n"
                "  0              Power-off the machine\n"
                "  6              Reboot the machine\n"
@@ -1479,7 +1526,7 @@ static int telinit_help(void) {
 
 static int runlevel_help(void) {
 
-        printf("%s [options]\n\n"
+        printf("%s [OPTIONS...]\n\n"
                "Prints the previous and current runlevel of the init system.\n\n"
                "     --help      Show this help\n",
                program_invocation_short_name);
@@ -1721,6 +1768,9 @@ static int shutdown_parse_argv(int argc, char *argv[]) {
                 }
         }
 
+        if (argc > optind && !streq(argv[optind], "now"))
+                log_warning("First argument '%s' isn't 'now'. Ignoring.", argv[optind]);
+
         /* We ignore the time argument */
         if (argc > optind + 1)
                 arg_wall = argv + optind + 1;
@@ -1728,7 +1778,6 @@ static int shutdown_parse_argv(int argc, char *argv[]) {
         optind = argc;
 
         return 1;
-
 }
 
 static int telinit_parse_argv(int argc, char *argv[]) {
@@ -1790,7 +1839,7 @@ static int telinit_parse_argv(int argc, char *argv[]) {
         }
 
         if (optind >= argc) {
-                log_error("Argument missing.");
+                telinit_help();
                 return -EINVAL;
         }
 
@@ -1891,14 +1940,150 @@ static int parse_argv(int argc, char *argv[]) {
         return systemctl_parse_argv(argc, argv);
 }
 
-static int talk_upstart(DBusConnection *bus) {
-        log_error("Talking upstart");
-        return 0;
+static int action_to_runlevel(void) {
+
+        static const char table[_ACTION_MAX] = {
+                [ACTION_HALT] =      '0',
+                [ACTION_POWEROFF] =  '0',
+                [ACTION_REBOOT] =    '6',
+                [ACTION_RUNLEVEL2] = '2',
+                [ACTION_RUNLEVEL3] = '3',
+                [ACTION_RUNLEVEL4] = '4',
+                [ACTION_RUNLEVEL5] = '5',
+                [ACTION_RESCUE] =    '1'
+        };
+
+        assert(arg_action < _ACTION_MAX);
+
+        return table[arg_action];
+}
+
+static int talk_upstart(void) {
+        DBusMessage *m = NULL, *reply = NULL;
+        DBusError error;
+        int previous, rl, r;
+        char
+                env1_buf[] = "RUNLEVEL=X",
+                env2_buf[] = "PREVLEVEL=X";
+        char *env1 = env1_buf, *env2 = env2_buf;
+        const char *emit = "runlevel";
+        dbus_bool_t b_false = FALSE;
+        DBusMessageIter iter, sub;
+        DBusConnection *bus;
+
+        dbus_error_init(&error);
+
+        if (!(rl = action_to_runlevel()))
+                return 0;
+
+        if (utmp_get_runlevel(&previous, NULL) < 0)
+                previous = 'N';
+
+        if (!(bus = dbus_connection_open("unix:abstract=/com/ubuntu/upstart", &error))) {
+                if (dbus_error_has_name(&error, DBUS_ERROR_NO_SERVER)) {
+                        r = 0;
+                        goto finish;
+                }
+
+                log_error("Failed to connect to Upstart bus: %s", error.message);
+                r = -EIO;
+                goto finish;
+        }
+
+        if ((r = bus_check_peercred(bus)) < 0) {
+                log_error("Failed to verify owner of bus.");
+                goto finish;
+        }
+
+        if (!(m = dbus_message_new_method_call(
+                              "com.ubuntu.Upstart",
+                              "/com/ubuntu/Upstart",
+                              "com.ubuntu.Upstart0_6",
+                              "EmitEvent"))) {
+
+                log_error("Could not allocate message.");
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        dbus_message_iter_init_append(m, &iter);
+
+        env1_buf[sizeof(env1_buf)-2] = rl;
+        env2_buf[sizeof(env2_buf)-2] = previous;
+
+        if (!dbus_message_iter_append_basic(&iter, DBUS_TYPE_STRING, &emit) ||
+            !dbus_message_iter_open_container(&iter, DBUS_TYPE_ARRAY, "s", &sub) ||
+            !dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &env1) ||
+            !dbus_message_iter_append_basic(&sub, DBUS_TYPE_STRING, &env2) ||
+            !dbus_message_iter_close_container(&iter, &sub) ||
+            !dbus_message_iter_append_basic(&iter, DBUS_TYPE_BOOLEAN, &b_false)) {
+                log_error("Could not append arguments to message.");
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        if (!(reply = dbus_connection_send_with_reply_and_block(bus, m, -1, &error))) {
+
+                if (error_is_no_service(&error)) {
+                        r = 0;
+                        goto finish;
+                }
+
+                log_error("Failed to issue method call: %s", error.message);
+                r = -EIO;
+                goto finish;
+        }
+
+        r = 1;
+
+finish:
+        if (m)
+                dbus_message_unref(m);
+
+        if (reply)
+                dbus_message_unref(reply);
+
+        if (bus)
+                dbus_connection_unref(bus);
+
+        dbus_error_free(&error);
+
+        return r;
 }
 
 static int talk_initctl(void) {
-        log_error("Talking initctl");
-        return 0;
+        struct init_request request;
+        int r, fd;
+        char rl;
+
+        if (!(rl = action_to_runlevel()))
+                return 0;
+
+        zero(request);
+        request.magic = INIT_MAGIC;
+        request.sleeptime = 0;
+        request.cmd = INIT_CMD_RUNLVL;
+        request.runlevel = rl;
+
+        if ((fd = open(INIT_FIFO, O_WRONLY|O_NDELAY|O_CLOEXEC|O_NOCTTY)) < 0) {
+
+                if (errno == ENOENT)
+                        return 0;
+
+                log_error("Failed to open "INIT_FIFO": %m");
+                return -errno;
+        }
+
+        errno = 0;
+        r = loop_write(fd, &request, sizeof(request), false) != sizeof(request);
+        close_nointr_nofail(fd);
+
+        if (r < 0) {
+                log_error("Failed to write to "INIT_FIFO": %m");
+                return errno ? -errno : -EIO;
+        }
+
+        return 1;
 }
 
 static int systemctl_main(DBusConnection *bus, int argc, char *argv[]) {
@@ -2028,13 +2213,17 @@ static int start_with_fallback(DBusConnection *bus) {
 
                 /* Hmm, talking to systemd via D-Bus didn't work. Then
                  * let's try to talk to Upstart via D-Bus. */
-                if ((r = talk_upstart(bus)) > 0)
+                if ((r = talk_upstart()) > 0)
                         return 0;
         }
 
         /* Nothing else worked, so let's try
          * /dev/initctl */
-        return talk_initctl();
+        if ((r = talk_initctl()) != 0)
+                return 0;
+
+        log_error("Failed to talk to init daemon.");
+        return -EIO;
 }
 
 static int halt_main(DBusConnection *bus) {
@@ -2120,7 +2309,18 @@ int main(int argc, char*argv[]) {
                 goto finish;
         }
 
-        if ((bus = dbus_bus_get(arg_session ? DBUS_BUS_SESSION : DBUS_BUS_SYSTEM, &error)))
+        /* If we are root, then let's not go via the bus */
+        if (geteuid() == 0 && !arg_session) {
+                bus = dbus_connection_open("unix:abstract=/org/freedesktop/systemd1/private", &error);
+
+                if (bus && bus_check_peercred(bus) < 0) {
+                        log_error("Failed to verify owner of bus.");
+                        goto finish;
+                }
+        } else
+                bus = dbus_bus_get(arg_session ? DBUS_BUS_SESSION : DBUS_BUS_SYSTEM, &error);
+
+        if (bus)
                 dbus_connection_set_exit_on_disconnect(bus, FALSE);
 
         switch (arg_action) {
@@ -2148,6 +2348,7 @@ int main(int argc, char*argv[]) {
         case ACTION_RUNLEVEL5:
         case ACTION_RESCUE:
         case ACTION_EMERGENCY:
+        case ACTION_DEFAULT:
                 retval = start_with_fallback(bus) < 0;
                 break;
 
@@ -2156,6 +2357,8 @@ int main(int argc, char*argv[]) {
                 retval = reload_with_fallback(bus) < 0;
                 break;
 
+        case ACTION_INVALID:
+        case ACTION_RUNLEVEL:
         default:
                 assert_not_reached("Unknown action");
         }