logind: introduce a state for session, being one of online, active, closing

online = logged in
active = logged in and session is in the fg
closing = nominally logged out but some left-over processes still around

Related to:

https://bugzilla.gnome.org/show_bug.cgi?id=677556

9 files changed, 106 insertions, 14 deletions

diff --git a/src/login/libsystemd-login.sym b/src/login/libsystemd-login.sym
index 0fd61e000b..347e0730a6 100644
--- a/src/login/libsystemd-login.sym
+++ b/src/login/libsystemd-login.sym
@@ -46,3 +46,8 @@ global:
         sd_session_get_class;
         sd_session_get_display;
 } LIBSYSTEMD_LOGIN_38;
+
+LIBSYSTEMD_LOGIN_186 {
+global:
+        sd_session_get_state;
+} LIBSYSTEMD_LOGIN_43;
diff --git a/src/login/loginctl.c b/src/login/loginctl.c
index 18f56f0124..a838a54086 100644
--- a/src/login/loginctl.c
+++ b/src/login/loginctl.c
@@ -364,7 +364,7 @@ typedef struct SessionStatusInfo {
         pid_t leader;
         const char *type;
         const char *class;
-        bool active;
+        const char *state;
 } SessionStatusInfo;
 
 typedef struct UserStatusInfo {
@@ -458,8 +458,8 @@ static void print_session_status_info(SessionStatusInfo *i) {
         } else if (i->class)
                 printf("\t   Class: %s\n", i->class);
 
-
-        printf("\t  Active: %s\n", yes_no(i->active));
+        if (i->state)
+                printf("\t   State: %s\n", i->state);
 
         if (i->default_control_group) {
                 unsigned c;
@@ -597,6 +597,8 @@ static int status_property_session(const char *name, DBusMessageIter *iter, Sess
                                 i->type = s;
                         else if (streq(name, "Class"))
                                 i->class = s;
+                        else if (streq(name, "State"))
+                                i->state = s;
                 }
                 break;
         }
@@ -621,8 +623,6 @@ static int status_property_session(const char *name, DBusMessageIter *iter, Sess
 
                 if (streq(name, "Remote"))
                         i->remote = b;
-                else if (streq(name, "Active"))
-                        i->active = b;
 
                 break;
         }
diff --git a/src/login/logind-session-dbus.c b/src/login/logind-session-dbus.c
index 7f1b58072d..9103781289 100644
--- a/src/login/logind-session-dbus.c
+++ b/src/login/logind-session-dbus.c
@@ -53,12 +53,13 @@
         "  <property name=\"Remote\" type=\"b\" access=\"read\"/>\n"    \
         "  <property name=\"RemoteHost\" type=\"s\" access=\"read\"/>\n" \
         "  <property name=\"RemoteUser\" type=\"s\" access=\"read\"/>\n" \
-        "  <property name=\"Service\" type=\"s\" access=\"read\"/>\n" \
+        "  <property name=\"Service\" type=\"s\" access=\"read\"/>\n"   \
         "  <property name=\"Leader\" type=\"u\" access=\"read\"/>\n"    \
         "  <property name=\"Audit\" type=\"u\" access=\"read\"/>\n"     \
         "  <property name=\"Type\" type=\"s\" access=\"read\"/>\n"      \
-        "  <property name=\"Class\" type=\"s\" access=\"read\"/>\n"      \
+        "  <property name=\"Class\" type=\"s\" access=\"read\"/>\n"     \
         "  <property name=\"Active\" type=\"b\" access=\"read\"/>\n"    \
+        "  <property name=\"State\" type=\"s\" access=\"read\"/>\n"     \
         "  <property name=\"Controllers\" type=\"as\" access=\"read\"/>\n" \
         "  <property name=\"ResetControllers\" type=\"as\" access=\"read\"/>\n" \
         "  <property name=\"KillProcesses\" type=\"b\" access=\"read\"/>\n" \
@@ -219,6 +220,22 @@ static int bus_session_append_default_cgroup(DBusMessageIter *i, const char *pro
 static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_session_append_type, session_type, SessionType);
 static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_session_append_class, session_class, SessionClass);
 
+static int bus_session_append_state(DBusMessageIter *i, const char *property, void *data) {
+        Session *s = data;
+        const char *state;
+
+        assert(i);
+        assert(property);
+        assert(s);
+
+        state = session_state_to_string(session_get_state(s));
+
+        if (!dbus_message_iter_append_basic(i, DBUS_TYPE_STRING, &state))
+                return -ENOMEM;
+
+        return 0;
+}
+
 static int get_session_for_path(Manager *m, const char *path, Session **_s) {
         Session *s;
         char *id;
@@ -262,6 +279,7 @@ static const BusProperty bus_login_session_properties[] = {
         { "Type",                   bus_session_append_type,            "s", offsetof(Session, type)                },
         { "Class",                  bus_session_append_class,           "s", offsetof(Session, class)               },
         { "Active",                 bus_session_append_active,          "b", 0 },
+        { "State",                  bus_session_append_state,           "s", 0 },
         { "Controllers",            bus_property_append_strv,          "as", offsetof(Session, controllers),        true },
         { "ResetControllers",       bus_property_append_strv,          "as", offsetof(Session, reset_controllers),  true },
         { "KillProcesses",          bus_property_append_bool,           "b", offsetof(Session, kill_processes)      },
diff --git a/src/login/logind-session.c b/src/login/logind-session.c
index 58514ea0d2..e438c66332 100644
--- a/src/login/logind-session.c
+++ b/src/login/logind-session.c
@@ -133,11 +133,13 @@ int session_save(Session *s) {
                 "UID=%lu\n"
                 "USER=%s\n"
                 "ACTIVE=%i\n"
+                "STATE=%s\n"
                 "REMOTE=%i\n"
                 "KILL_PROCESSES=%i\n",
                 (unsigned long) s->user->uid,
                 s->user->name,
                 session_is_active(s),
+                session_state_to_string(session_get_state(s)),
                 s->remote,
                 s->kill_processes);
 
@@ -913,6 +915,18 @@ void session_add_to_gc_queue(Session *s) {
         s->in_gc_queue = true;
 }
 
+SessionState session_get_state(Session *s) {
+        assert(s);
+
+        if (s->fifo_fd < 0)
+                return SESSION_CLOSING;
+
+        if (session_is_active(s))
+                return SESSION_ACTIVE;
+
+        return SESSION_ONLINE;
+}
+
 int session_kill(Session *s, KillWho who, int signo) {
         int r = 0;
         Set *pid_set = NULL;
@@ -954,6 +968,14 @@ int session_kill(Session *s, KillWho who, int signo) {
         return r;
 }
 
+static const char* const session_state_table[_SESSION_TYPE_MAX] = {
+        [SESSION_ONLINE] = "online",
+        [SESSION_ACTIVE] = "active",
+        [SESSION_CLOSING] = "closing"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(session_state, SessionState);
+
 static const char* const session_type_table[_SESSION_TYPE_MAX] = {
         [SESSION_TTY] = "tty",
         [SESSION_X11] = "x11",
diff --git a/src/login/logind-session.h b/src/login/logind-session.h
index 1afbdcc410..b255dc7cde 100644
--- a/src/login/logind-session.h
+++ b/src/login/logind-session.h
@@ -30,6 +30,14 @@ typedef struct Session Session;
 #include "logind-seat.h"
 #include "logind-user.h"
 
+typedef enum SessionState {
+        SESSION_ONLINE,   /* Logged in */
+        SESSION_ACTIVE,   /* Logged in and in the fg */
+        SESSION_CLOSING,  /* Logged out, but processes still remain */
+        _SESSION_STATE_MAX,
+        _SESSION_STATE_INVALID = -1
+} SessionState;
+
 typedef enum SessionType {
         SESSION_UNSPECIFIED,
         SESSION_TTY,
@@ -118,12 +126,17 @@ int session_kill(Session *s, KillWho who, int signo);
 
 char *session_bus_path(Session *s);
 
+SessionState session_get_state(Session *u);
+
 extern const DBusObjectPathVTable bus_session_vtable;
 
 int session_send_signal(Session *s, bool new_session);
 int session_send_changed(Session *s, const char *properties);
 int session_send_lock(Session *s, bool lock);
 
+const char* session_state_to_string(SessionState t);
+SessionState session_state_from_string(const char *s);
+
 const char* session_type_to_string(SessionType t);
 SessionType session_type_from_string(const char *s);
 
diff --git a/src/login/logind-user.h b/src/login/logind-user.h
index 93e5fd934a..cffac35447 100644
--- a/src/login/logind-user.h
+++ b/src/login/logind-user.h
@@ -30,11 +30,11 @@ typedef struct User User;
 #include "logind-session.h"
 
 typedef enum UserState {
-        USER_OFFLINE,
-        USER_LINGERING,
-        USER_ONLINE,
-        USER_ACTIVE,
-        USER_CLOSING,
+        USER_OFFLINE,    /* Not logged in at all */
+        USER_LINGERING,  /* Lingering has been enabled by the admin for this user */
+        USER_ONLINE,     /* User logged in */
+        USER_ACTIVE,     /* User logged in and has a session in the fg */
+        USER_CLOSING,    /* User logged out, but processes still remain and lingering is not enabled */
         _USER_STATE_MAX,
         _USER_STATE_INVALID = -1
 } UserState;
diff --git a/src/login/sd-login.c b/src/login/sd-login.c
index 912ced3179..223e121bed 100644
--- a/src/login/sd-login.c
+++ b/src/login/sd-login.c
@@ -317,6 +317,30 @@ _public_ int sd_session_is_active(const char *session) {
         return r;
 }
 
+_public_ int sd_session_get_state(const char *session, char **state) {
+        char *p, *s = NULL;
+        int r;
+
+        if (!state)
+                return -EINVAL;
+
+        r = file_of_session(session, &p);
+        if (r < 0)
+                return r;
+
+        r = parse_env_file(p, NEWLINE, "STATE", &s, NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+                return r;
+        } else if (!s)
+                return -EIO;
+
+        *state = s;
+        return 0;
+}
+
 _public_ int sd_session_get_uid(const char *session, uid_t *uid) {
         int r;
         char *p, *s = NULL;
diff --git a/src/login/test-login.c b/src/login/test-login.c
index 707cf21589..d0916ced6a 100644
--- a/src/login/test-login.c
+++ b/src/login/test-login.c
@@ -71,6 +71,11 @@ int main(int argc, char* argv[]) {
         assert_se(r >= 0);
         printf("active = %s\n", yes_no(r));
 
+        r = sd_session_get_state(session, &state);
+        assert_se(r >= 0);
+        printf("state = %s\n", state);
+        free(state);
+
         assert_se(sd_session_get_uid(session, &u) >= 0);
         printf("uid = %lu\n", (unsigned long) u);
         assert_se(u == u2);
diff --git a/src/systemd/sd-login.h b/src/systemd/sd-login.h
index 0a6d6ffdaa..bddc74e729 100644
--- a/src/systemd/sd-login.h
+++ b/src/systemd/sd-login.h
@@ -63,7 +63,7 @@ int sd_pid_get_owner_uid(pid_t pid, uid_t *uid);
  * error for non-service processes. */
 int sd_pid_get_unit(pid_t, char **unit);
 
-/* Get state from uid. Possible states: offline, lingering, online, active */
+/* Get state from uid. Possible states: offline, lingering, online, active, closing */
 int sd_uid_get_state(uid_t uid, char**state);
 
 /* Return 1 if uid has session on seat. If require_active is true will
@@ -80,9 +80,14 @@ int sd_uid_get_sessions(uid_t uid, int require_active, char ***sessions);
  * just return number of seats.*/
 int sd_uid_get_seats(uid_t uid, int require_active, char ***seats);
 
-/* Return 1 if the session is a active */
+/* Return 1 if the session is a active. */
 int sd_session_is_active(const char *session);
 
+/* Get state from session. Possible states: online, active, closing
+ * (This function is a more generic version of
+ * sd_session_is_active().) */
+int sd_session_get_state(const char *sessio, char **state);
+
 /* Determine user id of session */
 int sd_session_get_uid(const char *session, uid_t *uid);