chiark / gitweb /
logind: don't assert if the slice is missing
[elogind.git] / src / login / logind-session.c
index 8950c719058c3f6737cbb8393d22e042df7f796f..9b6f46b6faebd120ea6dd0615831133727da8fcb 100644 (file)
@@ -40,7 +40,7 @@
 #include "formats-util.h"
 #include "terminal-util.h"
 
-#define RELEASE_USEC (20*USEC_PER_SEC)
+// #define RELEASE_USEC (20*USEC_PER_SEC)
 
 static void session_remove_fifo(Session *s);
 
@@ -125,7 +125,10 @@ void session_free(Session *s) {
                 free(s->scope);
         }
 
+/// elogind does not support systemd scope_jobs
+#if 0
         free(s->scope_job);
+#endif // 0
 
         sd_bus_message_unref(s->create_message);
 
@@ -165,11 +168,11 @@ int session_save(Session *s) {
 
         r = mkdir_safe_label("/run/systemd/sessions", 0755, 0, 0);
         if (r < 0)
-                goto finish;
+                goto fail;
 
         r = fopen_temporary(s->state_file, &f, &temp_path);
         if (r < 0)
-                goto finish;
+                goto fail;
 
         assert(s->user);
 
@@ -196,8 +199,11 @@ int session_save(Session *s) {
 
         if (s->scope)
                 fprintf(f, "SCOPE=%s\n", s->scope);
+/// elogind does not support systemd scope_jobs
+#if 0
         if (s->scope_job)
                 fprintf(f, "SCOPE_JOB=%s\n", s->scope_job);
+#endif // 0
 
         if (s->fifo_path)
                 fprintf(f, "FIFO=%s\n", s->fifo_path);
@@ -217,7 +223,7 @@ int session_save(Session *s) {
                 escaped = cescape(s->remote_host);
                 if (!escaped) {
                         r = -ENOMEM;
-                        goto finish;
+                        goto fail;
                 }
 
                 fprintf(f, "REMOTE_HOST=%s\n", escaped);
@@ -229,7 +235,7 @@ int session_save(Session *s) {
                 escaped = cescape(s->remote_user);
                 if (!escaped) {
                         r = -ENOMEM;
-                        goto finish;
+                        goto fail;
                 }
 
                 fprintf(f, "REMOTE_USER=%s\n", escaped);
@@ -241,7 +247,7 @@ int session_save(Session *s) {
                 escaped = cescape(s->service);
                 if (!escaped) {
                         r = -ENOMEM;
-                        goto finish;
+                        goto fail;
                 }
 
                 fprintf(f, "SERVICE=%s\n", escaped);
@@ -254,7 +260,7 @@ int session_save(Session *s) {
                 escaped = cescape(s->desktop);
                 if (!escaped) {
                         r = -ENOMEM;
-                        goto finish;
+                        goto fail;
                 }
 
                 fprintf(f, "DESKTOP=%s\n", escaped);
@@ -282,21 +288,27 @@ int session_save(Session *s) {
         if (s->controller)
                 fprintf(f, "CONTROLLER=%s\n", s->controller);
 
-        fflush(f);
+        r = fflush_and_check(f);
+        if (r < 0)
+                goto fail;
 
-        if (ferror(f) || rename(temp_path, s->state_file) < 0) {
+        if (rename(temp_path, s->state_file) < 0) {
                 r = -errno;
-                unlink(s->state_file);
-                unlink(temp_path);
+                goto fail;
         }
 
-finish:
-        if (r < 0)
-                log_error_errno(r, "Failed to save session data %s: %m", s->state_file);
+        return 0;
 
-        return r;
+fail:
+        (void) unlink(s->state_file);
+
+        if (temp_path)
+                (void) unlink(temp_path);
+
+        return log_error_errno(r, "Failed to save session data %s: %m", s->state_file);
 }
 
+
 int session_load(Session *s) {
         _cleanup_free_ char *remote = NULL,
                 *seat = NULL,
@@ -318,7 +330,10 @@ int session_load(Session *s) {
         r = parse_env_file(s->state_file, NEWLINE,
                            "REMOTE",         &remote,
                            "SCOPE",          &s->scope,
+/// elogind does not support systemd scope_jobs
+#if 0
                            "SCOPE_JOB",      &s->scope_job,
+#endif // 0
                            "FIFO",           &s->fifo_path,
                            "SEAT",           &seat,
                            "TTY",            &s->tty,
@@ -493,17 +508,18 @@ int session_activate(Session *s) {
         return 0;
 }
 
+/// UNNEEDED by elogind
+#if 0
 static int session_start_scope(Session *s) {
-        int r;
+        int r = 0;
 
         assert(s);
         assert(s->user);
-        assert(s->user->slice);
 
         if (!s->scope) {
                 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
                 _cleanup_free_ char *description = NULL;
-                char *scope, *job = NULL;
+                char *scope = NULL; //, *job = NULL;
 
                 description = strjoin("Session ", s->id, " of user ", s->user->name, NULL);
                 if (!description)
@@ -513,7 +529,7 @@ static int session_start_scope(Session *s) {
                 if (!scope)
                         return log_oom();
 
-                r = manager_start_scope(s->manager, scope, s->leader, s->user->slice, description, "logind.service", "systemd-user-sessions.service", &error, &job);
+                r = manager_start_scope(s->manager, scope, s->leader, s->user->slice, description, "systemd-logind.service", "systemd-user-sessions.service", &error, &job);
                 if (r < 0) {
                         log_error("Failed to start session scope %s: %s %s",
                                   scope, bus_error_message(&error, r), error.name);
@@ -532,6 +548,27 @@ static int session_start_scope(Session *s) {
 
         return 0;
 }
+#endif // 0
+
+static int session_start_cgroup(Session *s) {
+        int r;
+
+        assert(s);
+        assert(s->user);
+        assert(s->leader > 0);
+
+        /* First, create our own group */
+        r = cg_create(SYSTEMD_CGROUP_CONTROLLER, s->id);
+        if (r < 0)
+                return log_error_errno(r, "Failed to create cgroup %s: %m", s->id);
+
+        r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, s->id, s->leader);
+        if (r < 0)
+                log_warning_errno(r, "Failed to attach PID %d to cgroup %s: %m", s->leader, s->id);
+
+        return 0;
+}
+
 
 int session_start(Session *s) {
         int r;
@@ -549,7 +586,13 @@ int session_start(Session *s) {
                 return r;
 
         /* Create cgroup */
+/// elogind does its own session management without systemd units,
+/// slices and scopes
+#if 0
         r = session_start_scope(s);
+#else
+        r = session_start_cgroup(s);
+#endif // 0
         if (r < 0)
                 return r;
 
@@ -590,6 +633,8 @@ int session_start(Session *s) {
         return 0;
 }
 
+/// UNNEEDED by elogind
+#if 0
 static int session_stop_scope(Session *s, bool force) {
         _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
         char *job = NULL;
@@ -619,6 +664,22 @@ static int session_stop_scope(Session *s, bool force) {
 
         return 0;
 }
+#endif // 0
+
+static int session_stop_cgroup(Session *s, bool force) {
+        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        int r;
+
+        assert(s);
+
+        if (force || manager_shall_kill(s->manager, s->user->name)) {
+                r = session_kill(s, KILL_ALL, SIGTERM);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
 
 int session_stop(Session *s, bool force) {
         int r;
@@ -630,11 +691,19 @@ int session_stop(Session *s, bool force) {
 
         s->timer_event_source = sd_event_source_unref(s->timer_event_source);
 
+        if (s->seat)
+                seat_evict_position(s->seat, s);
+
         /* We are going down, don't care about FIFOs anymore */
         session_remove_fifo(s);
 
         /* Kill cgroup */
+/// elogind does not start scopes, but sessions
+#if 0
         r = session_stop_scope(s, force);
+#else
+        r = session_stop_cgroup(s, force);
+#endif // 0
 
         s->stopping = true;
 
@@ -647,7 +716,6 @@ int session_stop(Session *s, bool force) {
 }
 
 int session_finalize(Session *s) {
-        int r = 0;
         SessionDevice *sd;
 
         assert(s);
@@ -666,11 +734,14 @@ int session_finalize(Session *s) {
 
         s->timer_event_source = sd_event_source_unref(s->timer_event_source);
 
+        if (s->seat)
+                seat_evict_position(s->seat, s);
+
         /* Kill session devices */
         while ((sd = hashmap_first(s->devices)))
                 session_device_free(sd);
 
-        unlink(s->state_file);
+        (void) unlink(s->state_file);
         session_add_to_gc_queue(s);
         user_add_to_gc_queue(s->user);
 
@@ -690,9 +761,11 @@ int session_finalize(Session *s) {
         user_save(s->user);
         user_send_changed(s->user, "Sessions", "Display", NULL);
 
-        return r;
+        return 0;
 }
 
+/// UNNEEDED by elogind
+#if 0
 static int release_timeout_callback(sd_event_source *es, uint64_t usec, void *userdata) {
         Session *s = userdata;
 
@@ -702,6 +775,7 @@ static int release_timeout_callback(sd_event_source *es, uint64_t usec, void *us
         session_stop(s, false);
         return 0;
 }
+#endif // 0
 
 int session_release(Session *s) {
         assert(s);
@@ -712,11 +786,19 @@ int session_release(Session *s) {
         if (s->timer_event_source)
                 return 0;
 
+        /* In systemd, session release is triggered by user jobs
+           dying.  In elogind we don't have that so go ahead and stop
+           now.  */
+#if 0
         return sd_event_add_time(s->manager->event,
                                  &s->timer_event_source,
                                  CLOCK_MONOTONIC,
                                  now(CLOCK_MONOTONIC) + RELEASE_USEC, 0,
                                  release_timeout_callback, s);
+
+#else
+        return session_stop(s, false);
+#endif // 0
 }
 
 bool session_is_active(Session *s) {
@@ -902,8 +984,7 @@ static void session_remove_fifo(Session *s) {
 
         if (s->fifo_path) {
                 unlink(s->fifo_path);
-                free(s->fifo_path);
-                s->fifo_path = NULL;
+                s->fifo_path = mfree(s->fifo_path);
         }
 }
 
@@ -921,11 +1002,18 @@ bool session_check_gc(Session *s, bool drop_not_started) {
                         return true;
         }
 
+/// elogind supports neither scopes nor jobs
+#if 0
         if (s->scope_job && manager_job_is_active(s->manager, s->scope_job))
                 return true;
 
         if (s->scope && manager_unit_is_active(s->manager, s->scope))
                 return true;
+#endif // 0
+
+        if ( s->user->manager
+          && (cg_is_empty_recursive (SYSTEMD_CGROUP_CONTROLLER, s->user->manager->cgroup_root) > 0) )
+                return true;
 
         return false;
 }
@@ -947,7 +1035,12 @@ SessionState session_get_state(Session *s) {
         if (s->stopping || s->timer_event_source)
                 return SESSION_CLOSING;
 
+/// elogind does not support systemd scope_jobs
+#if 0
         if (s->scope_job || s->fifo_fd < 0)
+#else
+        if (s->fifo_fd < 0)
+#endif // 0
                 return SESSION_OPENING;
 
         if (session_is_active(s))
@@ -959,10 +1052,31 @@ SessionState session_get_state(Session *s) {
 int session_kill(Session *s, KillWho who, int signo) {
         assert(s);
 
+/// Without direct cgroup support, elogind can not kill sessions
+#if 0
         if (!s->scope)
                 return -ESRCH;
 
         return manager_kill_unit(s->manager, s->scope, who, signo, NULL);
+#else
+        if (who == KILL_LEADER) {
+                if (s->leader <= 0)
+                        return -ESRCH;
+
+                /* FIXME: verify that leader is in cgroup?  */
+
+                if (kill(s->leader, signo) < 0) {
+                        return log_error_errno(errno, "Failed to kill process leader %d for session %s: %m", s->leader, s->id);
+                }
+                return 0;
+        } else {
+                bool sigcont = false;
+                bool ignore_self = true;
+                bool rem = true;
+                return cg_kill_recursive (SYSTEMD_CGROUP_CONTROLLER, s->id, signo,
+                                          sigcont, ignore_self, rem, NULL);
+        }
+#endif // 0
 }
 
 static int session_open_vt(Session *s) {
@@ -975,7 +1089,7 @@ static int session_open_vt(Session *s) {
                 return s->vtfd;
 
         sprintf(path, "/dev/tty%u", s->vtnr);
-        s->vtfd = open(path, O_RDWR | O_CLOEXEC | O_NONBLOCK | O_NOCTTY);
+        s->vtfd = open_terminal(path, O_RDWR | O_CLOEXEC | O_NONBLOCK | O_NOCTTY);
         if (s->vtfd < 0)
                 return log_error_errno(errno, "cannot open VT %s of session %s: %m", path, s->id);
 
@@ -995,22 +1109,25 @@ int session_prepare_vt(Session *s) {
 
         r = fchown(vt, s->user->uid, -1);
         if (r < 0) {
-                r = -errno;
-                log_error_errno(errno, "Cannot change owner of /dev/tty%u: %m", s->vtnr);
+                r = log_error_errno(errno,
+                                    "Cannot change owner of /dev/tty%u: %m",
+                                    s->vtnr);
                 goto error;
         }
 
         r = ioctl(vt, KDSKBMODE, K_OFF);
         if (r < 0) {
-                r = -errno;
-                log_error_errno(errno, "Cannot set K_OFF on /dev/tty%u: %m", s->vtnr);
+                r = log_error_errno(errno,
+                                    "Cannot set K_OFF on /dev/tty%u: %m",
+                                    s->vtnr);
                 goto error;
         }
 
         r = ioctl(vt, KDSETMODE, KD_GRAPHICS);
         if (r < 0) {
-                r = -errno;
-                log_error_errno(errno, "Cannot set KD_GRAPHICS on /dev/tty%u: %m", s->vtnr);
+                r = log_error_errno(errno,
+                                    "Cannot set KD_GRAPHICS on /dev/tty%u: %m",
+                                    s->vtnr);
                 goto error;
         }
 
@@ -1022,8 +1139,9 @@ int session_prepare_vt(Session *s) {
         mode.acqsig = SIGRTMIN + 1;
         r = ioctl(vt, VT_SETMODE, &mode);
         if (r < 0) {
-                r = -errno;
-                log_error_errno(errno, "Cannot set VT_PROCESS on /dev/tty%u: %m", s->vtnr);
+                r = log_error_errno(errno,
+                                    "Cannot set VT_PROCESS on /dev/tty%u: %m",
+                                    s->vtnr);
                 goto error;
         }
 
@@ -1035,11 +1153,26 @@ error:
 }
 
 void session_restore_vt(Session *s) {
+
+        static const struct vt_mode mode = {
+                .mode = VT_AUTO,
+        };
+
         _cleanup_free_ char *utf8 = NULL;
-        int vt, kb = K_XLATE;
-        struct vt_mode mode = { 0 };
+        int vt, kb, old_fd;
+
+        /* We need to get a fresh handle to the virtual terminal,
+         * since the old file-descriptor is potentially in a hung-up
+         * state after the controlling process exited; we do a
+         * little dance to avoid having the terminal be available
+         * for reuse before we've cleaned it up.
+         */
+        old_fd = s->vtfd;
+        s->vtfd = -1;
 
         vt = session_open_vt(s);
+        safe_close(old_fd);
+
         if (vt < 0)
                 return;
 
@@ -1047,13 +1180,13 @@ void session_restore_vt(Session *s) {
 
         if (read_one_line_file("/sys/module/vt/parameters/default_utf8", &utf8) >= 0 && *utf8 == '1')
                 kb = K_UNICODE;
+        else
+                kb = K_XLATE;
 
         (void) ioctl(vt, KDSKBMODE, kb);
 
-        mode.mode = VT_AUTO;
         (void) ioctl(vt, VT_SETMODE, &mode);
-
-        fchown(vt, 0, -1);
+        (void) fchown(vt, 0, (gid_t) -1);
 
         s->vtfd = safe_close(s->vtfd);
 }
@@ -1108,7 +1241,18 @@ static void session_release_controller(Session *s, bool notify) {
                 session_device_free(sd);
 
         s->controller = NULL;
-        manager_drop_busname(s->manager, name);
+        s->track = sd_bus_track_unref(s->track);
+}
+
+static int on_bus_track(sd_bus_track *track, void *userdata) {
+        Session *s = userdata;
+
+        assert(track);
+        assert(s);
+
+        session_drop_controller(s);
+
+        return 0;
 }
 
 int session_set_controller(Session *s, const char *sender, bool force) {
@@ -1127,8 +1271,13 @@ int session_set_controller(Session *s, const char *sender, bool force) {
         if (!name)
                 return -ENOMEM;
 
-        r = manager_watch_busname(s->manager, name);
-        if (r)
+        s->track = sd_bus_track_unref(s->track);
+        r = sd_bus_track_new(s->manager->bus, &s->track, on_bus_track, s);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_track_add_name(s->track, name);
+        if (r < 0)
                 return r;
 
         /* When setting a session controller, we forcibly mute the VT and set
@@ -1141,7 +1290,7 @@ int session_set_controller(Session *s, const char *sender, bool force) {
          * or reset the VT in case it crashed/exited, too. */
         r = session_prepare_vt(s);
         if (r < 0) {
-                manager_drop_busname(s->manager, name);
+                s->track = sd_bus_track_unref(s->track);
                 return r;
         }
 
@@ -1159,6 +1308,7 @@ void session_drop_controller(Session *s) {
         if (!s->controller)
                 return;
 
+        s->track = sd_bus_track_unref(s->track);
         session_release_controller(s, false);
         session_save(s);
         session_restore_vt(s);