X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Flogin%2Flogind-session.c;h=ea1831dac692425dddf8299d93a90b0db73357fa;hb=c9a267b1b7009065a67dbf2c638b03c6801f7bbe;hp=9d05faf47ceab9aa60cb99b84aaa967d867e6333;hpb=e9e74f28d783a052dce7edfa94d7918bb591ba7a;p=elogind.git

diff --git a/src/login/logind-session.c b/src/login/logind-session.c
index 9d05faf47..ea1831dac 100644
--- a/src/login/logind-session.c
+++ b/src/login/logind-session.c
@@ -44,21 +44,6 @@
 
 static void session_remove_fifo(Session *s);
 
-static unsigned long devt_hash_func(const void *p, const uint8_t hash_key[HASH_KEY_SIZE]) {
-        uint64_t u = *(const dev_t*)p;
-
-        return uint64_hash_func(&u, hash_key);
-}
-
-static int devt_compare_func(const void *_a, const void *_b) {
-        dev_t a, b;
-
-        a = *(const dev_t*) _a;
-        b = *(const dev_t*) _b;
-
-        return a < b ? -1 : (a > b ? 1 : 0);
-}
-
 Session* session_new(Manager *m, const char *id) {
         Session *s;
 
@@ -76,7 +61,7 @@ Session* session_new(Manager *m, const char *id) {
                 return NULL;
         }
 
-        s->devices = hashmap_new(devt_hash_func, devt_compare_func);
+        s->devices = hashmap_new(&devt_hash_ops);
         if (!s->devices) {
                 free(s->state_file);
                 free(s);
@@ -307,7 +292,7 @@ int session_save(Session *s) {
 
 finish:
         if (r < 0)
-                log_error("Failed to save session data %s: %s", s->state_file, strerror(-r));
+                log_error_errno(r, "Failed to save session data %s: %m", s->state_file);
 
         return r;
 }
@@ -352,10 +337,8 @@ int session_load(Session *s) {
                            "CONTROLLER",     &controller,
                            NULL);
 
-        if (r < 0) {
-                log_error("Failed to read %s: %s", s->state_file, strerror(-r));
-                return r;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Failed to read %s: %m", s->state_file);
 
         if (!s->user) {
                 uid_t u;
@@ -564,11 +547,11 @@ int session_start(Session *s) {
                 return r;
 
         log_struct(s->class == SESSION_BACKGROUND ? LOG_DEBUG : LOG_INFO,
-                   MESSAGE_ID(SD_MESSAGE_SESSION_START),
+                   LOG_MESSAGE_ID(SD_MESSAGE_SESSION_START),
                    "SESSION_ID=%s", s->id,
                    "USER_ID=%s", s->user->name,
                    "LEADER="PID_FMT, s->leader,
-                   "MESSAGE=New session %s of user %s.", s->id, s->user->name,
+                   LOG_MESSAGE("New session %s of user %s.", s->id, s->user->name),
                    NULL);
 
         if (!dual_timestamp_is_set(&s->timestamp))
@@ -667,11 +650,11 @@ int session_finalize(Session *s) {
 
         if (s->started)
                 log_struct(s->class == SESSION_BACKGROUND ? LOG_DEBUG : LOG_INFO,
-                           MESSAGE_ID(SD_MESSAGE_SESSION_STOP),
+                           LOG_MESSAGE_ID(SD_MESSAGE_SESSION_STOP),
                            "SESSION_ID=%s", s->id,
                            "USER_ID=%s", s->user->name,
                            "LEADER="PID_FMT, s->leader,
-                           "MESSAGE=Removed session %s.", s->id,
+                           LOG_MESSAGE("Removed session %s.", s->id),
                            NULL);
 
         s->timer_event_source = sd_event_source_unref(s->timer_event_source);
@@ -984,10 +967,8 @@ static int session_open_vt(Session *s) {
 
         sprintf(path, "/dev/tty%u", s->vtnr);
         s->vtfd = open(path, O_RDWR | O_CLOEXEC | O_NONBLOCK | O_NOCTTY);
-        if (s->vtfd < 0) {
-                log_error("cannot open VT %s of session %s: %m", path, s->id);
-                return -errno;
-        }
+        if (s->vtfd < 0)
+                return log_error_errno(errno, "cannot open VT %s of session %s: %m", path, s->id);
 
         return s->vtfd;
 }
@@ -1006,21 +987,21 @@ int session_prepare_vt(Session *s) {
         r = fchown(vt, s->user->uid, -1);
         if (r < 0) {
                 r = -errno;
-                log_error("Cannot change owner of /dev/tty%u: %m", s->vtnr);
+                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("Cannot set K_OFF on /dev/tty%u: %m", s->vtnr);
+                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("Cannot set KD_GRAPHICS on /dev/tty%u: %m", s->vtnr);
+                log_error_errno(errno, "Cannot set KD_GRAPHICS on /dev/tty%u: %m", s->vtnr);
                 goto error;
         }
 
@@ -1033,7 +1014,7 @@ int session_prepare_vt(Session *s) {
         r = ioctl(vt, VT_SETMODE, &mode);
         if (r < 0) {
                 r = -errno;
-                log_error("Cannot set VT_PROCESS on /dev/tty%u: %m", s->vtnr);
+                log_error_errno(errno, "Cannot set VT_PROCESS on /dev/tty%u: %m", s->vtnr);
                 goto error;
         }
 
@@ -1068,36 +1049,61 @@ void session_restore_vt(Session *s) {
         s->vtfd = safe_close(s->vtfd);
 }
 
+void session_leave_vt(Session *s) {
+        int r;
+
+        assert(s);
+
+        /* This is called whenever we get a VT-switch signal from the kernel.
+         * We acknowledge all of them unconditionally. Note that session are
+         * free to overwrite those handlers and we only register them for
+         * sessions with controllers. Legacy sessions are not affected.
+         * However, if we switch from a non-legacy to a legacy session, we must
+         * make sure to pause all device before acknowledging the switch. We
+         * process the real switch only after we are notified via sysfs, so the
+         * legacy session might have already started using the devices. If we
+         * don't pause the devices before the switch, we might confuse the
+         * session we switch to. */
+
+        if (s->vtfd < 0)
+                return;
+
+        session_device_pause_all(s);
+        r = ioctl(s->vtfd, VT_RELDISP, 1);
+        if (r < 0)
+                log_debug_errno(errno, "Cannot release VT of session %s: %m", s->id);
+}
+
 bool session_is_controller(Session *s, const char *sender) {
         assert(s);
 
         return streq_ptr(s->controller, sender);
 }
 
-static void session_swap_controller(Session *s, char *name) {
+static void session_release_controller(Session *s, bool notify) {
+        _cleanup_free_ char *name = NULL;
         SessionDevice *sd;
 
-        if (s->controller) {
-                manager_drop_busname(s->manager, s->controller);
-                free(s->controller);
-                s->controller = NULL;
+        if (!s->controller)
+                return;
 
-                /* Drop all devices as they're now unused. Do that after the
-                 * controller is released to avoid sending out useles
-                 * dbus signals. */
-                while ((sd = hashmap_first(s->devices)))
-                        session_device_free(sd);
+        name = s->controller;
 
-                if (!name)
-                        session_restore_vt(s);
-        }
+        /* By resetting the controller before releasing the devices, we won't
+         * send notification signals. This avoids sending useless notifications
+         * if the controller is released on disconnects. */
+        if (!notify)
+                s->controller = NULL;
 
-        s->controller = name;
-        session_save(s);
+        while ((sd = hashmap_first(s->devices)))
+                session_device_free(sd);
+
+        s->controller = NULL;
+        manager_drop_busname(s->manager, name);
 }
 
 int session_set_controller(Session *s, const char *sender, bool force) {
-        char *t;
+        _cleanup_free_ char *name = NULL;
         int r;
 
         assert(s);
@@ -1108,15 +1114,13 @@ int session_set_controller(Session *s, const char *sender, bool force) {
         if (s->controller && !force)
                 return -EBUSY;
 
-        t = strdup(sender);
-        if (!t)
+        name = strdup(sender);
+        if (!name)
                 return -ENOMEM;
 
-        r = manager_watch_busname(s->manager, sender);
-        if (r) {
-                free(t);
+        r = manager_watch_busname(s->manager, name);
+        if (r)
                 return r;
-        }
 
         /* When setting a session controller, we forcibly mute the VT and set
          * it into graphics-mode. Applications can override that by changing
@@ -1127,10 +1131,15 @@ int session_set_controller(Session *s, const char *sender, bool force) {
          * If logind crashes/restarts, we restore the controller during restart
          * or reset the VT in case it crashed/exited, too. */
         r = session_prepare_vt(s);
-        if (r < 0)
+        if (r < 0) {
+                manager_drop_busname(s->manager, name);
                 return r;
+        }
 
-        session_swap_controller(s, t);
+        session_release_controller(s, true);
+        s->controller = name;
+        name = NULL;
+        session_save(s);
 
         return 0;
 }
@@ -1141,7 +1150,9 @@ void session_drop_controller(Session *s) {
         if (!s->controller)
                 return;
 
-        session_swap_controller(s, NULL);
+        session_release_controller(s, false);
+        session_save(s);
+        session_restore_vt(s);
 }
 
 static const char* const session_state_table[_SESSION_STATE_MAX] = {