logind: introduce session "positions"

[elogind.git] / src / login / logind-seat.c

diff --git a/src/login/logind-seat.c b/src/login/logind-seat.c
index b30c4ce9e8925b5ec57dbd8b7b8e87370afc87bb..b8f18c47a33bc715327e39369730a756c9430593 100644 (file)
--- a/src/login/logind-seat.c
+++ b/src/login/logind-seat.c
@@ -51,7 +51,7 @@ Seat *seat_new(Manager *m, const char *id) {
                 return NULL;
         }
 
-        s->id = path_get_file_name(s->state_file);
+        s->id = basename(s->state_file);
         s->manager = m;
 
         if (hashmap_put(m->seats, s->id, s) < 0) {
@@ -79,6 +79,7 @@ void seat_free(Seat *s) {
 
         hashmap_remove(s->manager->seats, s->id);
 
+        free(s->positions);
         free(s->state_file);
         free(s);
 }
@@ -166,13 +167,13 @@ int seat_load(Seat *s) {
         return 0;
 }
 
-static int vt_allocate(int vtnr) {
+static int vt_allocate(unsigned int vtnr) {
         _cleanup_free_ char *p = NULL;
         _cleanup_close_ int fd = -1;
 
         assert(vtnr >= 1);
 
-        if (asprintf(&p, "/dev/tty%i", vtnr) < 0)
+        if (asprintf(&p, "/dev/tty%u", vtnr) < 0)
                 return -ENOMEM;
 
         fd = open_terminal(p, O_RDWR|O_NOCTTY|O_CLOEXEC);
@@ -270,7 +271,61 @@ int seat_set_active(Seat *s, Session *session) {
         return 0;
 }
 
-int seat_active_vt_changed(Seat *s, int vtnr) {
+int seat_switch_to(Seat *s, unsigned int num) {
+        /* Public session positions skip 0 (there is only F1-F12). Maybe it
+         * will get reassigned in the future, so return error for now. */
+        if (!num)
+                return -EINVAL;
+
+        if (num >= s->position_count || !s->positions[num])
+                return -EINVAL;
+
+        return session_activate(s->positions[num]);
+}
+
+int seat_switch_to_next(Seat *s) {
+        unsigned int start, i;
+
+        if (!s->position_count)
+                return -EINVAL;
+
+        start = 1;
+        if (s->active && s->active->pos > 0)
+                start = s->active->pos;
+
+        for (i = start + 1; i < s->position_count; ++i)
+                if (s->positions[i])
+                        return session_activate(s->positions[i]);
+
+        for (i = 1; i < start; ++i)
+                if (s->positions[i])
+                        return session_activate(s->positions[i]);
+
+        return -EINVAL;
+}
+
+int seat_switch_to_previous(Seat *s) {
+        unsigned int start, i;
+
+        if (!s->position_count)
+                return -EINVAL;
+
+        start = 1;
+        if (s->active && s->active->pos > 0)
+                start = s->active->pos;
+
+        for (i = start - 1; i > 0; --i)
+                if (s->positions[i])
+                        return session_activate(s->positions[i]);
+
+        for (i = s->position_count - 1; i > start; --i)
+                if (s->positions[i])
+                        return session_activate(s->positions[i]);
+
+        return -EINVAL;
+}
+
+int seat_active_vt_changed(Seat *s, unsigned int vtnr) {
         Session *i, *new_active = NULL;
         int r;
 
@@ -280,7 +335,7 @@ int seat_active_vt_changed(Seat *s, int vtnr) {
         if (!seat_has_vts(s))
                 return -EINVAL;
 
-        log_debug("VT changed to %i", vtnr);
+        log_debug("VT changed to %u", vtnr);
 
         LIST_FOREACH(sessions_by_seat, i, s->sessions)
                 if (i->vtnr == vtnr) {
@@ -297,7 +352,8 @@ int seat_active_vt_changed(Seat *s, int vtnr) {
 int seat_read_active_vt(Seat *s) {
         char t[64];
         ssize_t k;
-        int r, vtnr;
+        unsigned int vtnr;
+        int r;
 
         assert(s);
 
@@ -320,13 +376,13 @@ int seat_read_active_vt(Seat *s) {
                 return -EIO;
         }
 
-        r = safe_atoi(t+3, &vtnr);
+        r = safe_atou(t+3, &vtnr);
         if (r < 0) {
                 log_error("Failed to parse VT number %s", t+3);
                 return r;
         }
 
-        if (vtnr <= 0) {
+        if (!vtnr) {
                 log_error("VT number invalid: %s", t+3);
                 return -EIO;
         }
@@ -402,19 +458,63 @@ int seat_stop_sessions(Seat *s) {
         return r;
 }
 
+void seat_evict_position(Seat *s, Session *session) {
+        unsigned int pos = session->pos;
+
+        session->pos = 0;
+
+        if (!pos)
+                return;
+
+        if (pos < s->position_count && s->positions[pos] == session)
+                s->positions[pos] = NULL;
+}
+
+void seat_claim_position(Seat *s, Session *session, unsigned int pos) {
+        /* with VTs, the position is always the same as the VTnr */
+        if (seat_has_vts(s))
+                pos = session->vtnr;
+
+        if (!GREEDY_REALLOC0(s->positions, s->position_count, pos + 1))
+                return;
+
+        seat_evict_position(s, session);
+
+        session->pos = pos;
+        if (pos > 0 && !s->positions[pos])
+                s->positions[pos] = session;
+}
+
+static void seat_assign_position(Seat *s, Session *session) {
+        unsigned int pos;
+
+        if (session->pos > 0)
+                return;
+
+        for (pos = 1; pos < s->position_count; ++pos)
+                if (!s->positions[pos])
+                        break;
+
+        seat_claim_position(s, session, pos);
+}
+
 int seat_attach_session(Seat *s, Session *session) {
         assert(s);
         assert(session);
         assert(!session->seat);
 
+        if (!seat_has_vts(s) != !session->vtnr)
+                return -EINVAL;
+
         session->seat = s;
         LIST_PREPEND(sessions_by_seat, s->sessions, session);
+        seat_assign_position(s, session);
 
         seat_send_changed(s, "Sessions", NULL);
 
         /* On seats with VTs, the VT logic defines which session is active. On
-         * seats without VTs, we automatically activate the first session. */
-        if (!seat_has_vts(s) && !s->active)
+         * seats without VTs, we automatically activate new sessions. */
+        if (!seat_has_vts(s))
                 seat_set_active(s, session);
 
         return 0;