logind: kill a session as soon as its pipe fd gets EOF

[elogind.git] / src / logind.c

diff --git a/src/logind.c b/src/logind.c
index 2665ab910d95f08c20b29d529ff6fae6dd651b30..8507c2e152a50f05b64b6f395fd2fd26764e3374 100644 (file)
--- a/src/logind.c
+++ b/src/logind.c
@@ -33,12 +33,6 @@
 #include "dbus-common.h"
 #include "dbus-loop.h"
 
-enum {
-        FD_UDEV,
-        FD_CONSOLE,
-        FD_BUS
-};
-
 Manager *manager_new(void) {
         Manager *m;
 
@@ -57,6 +51,7 @@ Manager *manager_new(void) {
         m->sessions = hashmap_new(string_hash_func, string_compare_func);
         m->users = hashmap_new(trivial_hash_func, trivial_compare_func);
         m->cgroups = hashmap_new(string_hash_func, string_compare_func);
+        m->pipe_fds = hashmap_new(trivial_hash_func, trivial_compare_func);
 
         if (!m->devices || !m->seats || !m->sessions || !m->users) {
                 manager_free(m);
@@ -102,6 +97,7 @@ void manager_free(Manager *m) {
         hashmap_free(m->devices);
         hashmap_free(m->seats);
         hashmap_free(m->cgroups);
+        hashmap_free(m->pipe_fds);
 
         if (m->console_active_fd >= 0)
                 close_nointr_nofail(m->console_active_fd);
@@ -656,7 +652,13 @@ static int vt_is_busy(int vtnr) {
 
         assert(vtnr >= 1);
 
-        fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC);
+        /* We explicitly open /dev/tty1 here instead of /dev/tty0. If
+         * we'd open the latter we'd open the foreground tty which
+         * hence would be unconditionally busy. By opening /dev/tty1
+         * we avoid this. Since tty1 is special and needs to be an
+         * explicitly loaded getty or DM this is safe. */
+
+        fd = open_terminal("/dev/tty1", O_RDWR|O_NOCTTY|O_CLOEXEC);
         if (fd < 0)
                 return -errno;
 
@@ -672,16 +674,61 @@ static int vt_is_busy(int vtnr) {
 
 int manager_spawn_autovt(Manager *m, int vtnr) {
         int r;
+        DBusMessage *message = NULL, *reply = NULL;
+        char *name = NULL;
+        const char *mode = "fail";
+        DBusError error;
 
         assert(m);
 
+        dbus_error_init(&error);
+
         r = vt_is_busy(vtnr);
         if (r != 0)
                 return r;
 
-        /* ... */
+        message = dbus_message_new_method_call("org.freedesktop.systemd1", "/org/freedesktop/systemd1", "org.freedesktop.systemd1.Manager", "StartUnit");
+        if (!message) {
+                log_error("Could not allocate message.");
+                r = -ENOMEM;
+                goto finish;
+        }
 
-        return 0;
+        if (asprintf(&name, "autovt-getty@tty%i.service", vtnr) < 0) {
+                log_error("Could not allocate service name.");
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        if (!dbus_message_append_args(message,
+                                      DBUS_TYPE_STRING, &name,
+                                      DBUS_TYPE_STRING, &mode,
+                                      DBUS_TYPE_INVALID)) {
+                log_error("Could not attach target and flag information to message.");
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        reply = dbus_connection_send_with_reply_and_block(m->bus, message, -1, &error);
+        if (!reply) {
+                log_error("Failed to start unit: %s", bus_error_message(&error));
+                goto finish;
+        }
+
+        r = 0;
+
+finish:
+        free(name);
+
+        if (message)
+                dbus_message_unref(message);
+
+        if (reply)
+                dbus_message_unref(reply);
+
+        dbus_error_free(&error);
+
+        return r;
 }
 
 void manager_cgroup_notify_empty(Manager *m, const char *cgroup) {
@@ -714,6 +761,19 @@ void manager_cgroup_notify_empty(Manager *m, const char *cgroup) {
         free(p);
 }
 
+static void manager_pipe_notify_eof(Manager *m, int fd) {
+        Session *s;
+
+        assert_se(m);
+        assert_se(fd >= 0);
+
+        assert_se(s = hashmap_get(m->pipe_fds, INT_TO_PTR(fd + 1)));
+        assert(s->pipe_fd == fd);
+        session_unset_pipe_fd(s);
+
+        session_stop(s);
+}
+
 static int manager_connect_bus(Manager *m) {
         DBusError error;
         int r;
@@ -727,7 +787,7 @@ static int manager_connect_bus(Manager *m) {
 
         m->bus = dbus_bus_get_private(DBUS_BUS_SYSTEM, &error);
         if (!m->bus) {
-                log_error("Failed to get system D-Bus connection: %s", error.message);
+                log_error("Failed to get system D-Bus connection: %s", bus_error_message(&error));
                 r = -ECONNREFUSED;
                 goto fail;
         }
@@ -750,13 +810,20 @@ static int manager_connect_bus(Manager *m) {
                            &error);
 
         if (dbus_error_is_set(&error)) {
-                log_error("Failed to register match: %s", error.message);
+                log_error("Failed to register match: %s", bus_error_message(&error));
+                r = -EIO;
+                goto fail;
+        }
+
+        r = dbus_bus_request_name(m->bus, "org.freedesktop.login1", DBUS_NAME_FLAG_DO_NOT_QUEUE, &error);
+        if (dbus_error_is_set(&error)) {
+                log_error("Failed to register name on bus: %s", bus_error_message(&error));
                 r = -EIO;
                 goto fail;
         }
 
-        if (dbus_bus_request_name(m->bus, "org.freedesktop.login1", DBUS_NAME_FLAG_DO_NOT_QUEUE, &error) < 0) {
-                log_error("Failed to register name on bus: %s", error.message);
+        if (r != DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER)  {
+                log_error("Failed to acquire name.");
                 r = -EEXIST;
                 goto fail;
         }
@@ -1006,6 +1073,10 @@ int manager_run(Manager *m) {
                 case FD_BUS:
                         bus_loop_dispatch(m->bus_fd);
                         break;
+
+                default:
+                        if (event.data.u32 >= FD_PIPE_BASE)
+                                manager_pipe_notify_eof(m, event.data.u32 - FD_PIPE_BASE);
                 }
         }