Merge pull request #1854 from poettering/unit-deps

Dependency engine improvements

10 files changed, 146 insertions, 91 deletions

diff --git a/src/core/automount.c b/src/core/automount.c
index 4c229247c5..41ead117c8 100644
--- a/src/core/automount.c
+++ b/src/core/automount.c
@@ -148,6 +148,9 @@ static int automount_add_default_dependencies(Automount *a) {
 
         assert(a);
 
+        if (!UNIT(a)->default_dependencies)
+                return 0;
+
         if (UNIT(a)->manager->running_as != MANAGER_SYSTEM)
                 return 0;
 
@@ -219,11 +222,9 @@ static int automount_load(Unit *u) {
                 if (r < 0)
                         return r;
 
-                if (UNIT(a)->default_dependencies) {
-                        r = automount_add_default_dependencies(a);
-                        if (r < 0)
-                                return r;
-                }
+                r = automount_add_default_dependencies(a);
+                if (r < 0)
+                        return r;
         }
 
         return automount_verify(a);
diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
index 53d96dee14..18cbbf0dcc 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -122,7 +122,7 @@ int config_parse_unit_deps(const char *unit,
                 _cleanup_free_ char *word = NULL, *k = NULL;
                 int r;
 
-                r = extract_first_word(&p, &word, NULL, 0);
+                r = extract_first_word(&p, &word, NULL, EXTRACT_RETAIN_ESCAPE);
                 if (r == 0)
                         break;
                 if (r == -ENOMEM)
diff --git a/src/core/mount.c b/src/core/mount.c
index d3766ba934..e86bcf3830 100644
--- a/src/core/mount.c
+++ b/src/core/mount.c
@@ -387,12 +387,15 @@ static bool should_umount(Mount *m) {
 }
 
 static int mount_add_default_dependencies(Mount *m) {
-        const char *after, *after2, *online;
         MountParameters *p;
+        const char *after;
         int r;
 
         assert(m);
 
+        if (!UNIT(m)->default_dependencies)
+                return 0;
+
         if (UNIT(m)->manager->running_as != MANAGER_SYSTEM)
                 return 0;
 
@@ -413,30 +416,34 @@ static int mount_add_default_dependencies(Mount *m) {
                 return 0;
 
         if (mount_is_network(p)) {
-                after = SPECIAL_REMOTE_FS_PRE_TARGET;
-                after2 = SPECIAL_NETWORK_TARGET;
-                online = SPECIAL_NETWORK_ONLINE_TARGET;
-        } else {
-                after = SPECIAL_LOCAL_FS_PRE_TARGET;
-                after2 = NULL;
-                online = NULL;
-        }
+                /* We order ourselves after network.target. This is
+                 * primarily useful at shutdown: services that take
+                 * down the network should order themselves before
+                 * network.target, so that they are shut down only
+                 * after this mount unit is stopped. */
 
-        r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, after, NULL, true);
-        if (r < 0)
-                return r;
-
-        if (after2) {
-                r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, after2, NULL, true);
+                r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, SPECIAL_NETWORK_TARGET, NULL, true);
                 if (r < 0)
                         return r;
-        }
 
-        if (online) {
-                r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_WANTS, UNIT_AFTER, online, NULL, true);
+                /* We pull in network-online.target, and order
+                 * ourselves after it. This is useful at start-up to
+                 * actively pull in tools that want to be started
+                 * before we start mounting network file systems, and
+                 * whose purpose it is to delay this until the network
+                 * is "up". */
+
+                r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_WANTS, UNIT_AFTER, SPECIAL_NETWORK_ONLINE_TARGET, NULL, true);
                 if (r < 0)
                         return r;
-        }
+
+                after = SPECIAL_REMOTE_FS_PRE_TARGET;
+        } else
+                after = SPECIAL_LOCAL_FS_PRE_TARGET;
+
+        r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, after, NULL, true);
+        if (r < 0)
+                return r;
 
         if (should_umount(m)) {
                 r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true);
@@ -533,11 +540,9 @@ static int mount_add_extras(Mount *m) {
         if (r < 0)
                 return r;
 
-        if (u->default_dependencies) {
-                r = mount_add_default_dependencies(m);
-                if (r < 0)
-                        return r;
-        }
+        r = mount_add_default_dependencies(m);
+        if (r < 0)
+                return r;
 
         return 0;
 }
diff --git a/src/core/path.c b/src/core/path.c
index 35e1753583..c0992b4fcc 100644
--- a/src/core/path.c
+++ b/src/core/path.c
@@ -315,20 +315,20 @@ static int path_add_default_dependencies(Path *p) {
 
         assert(p);
 
-        r = unit_add_dependency_by_name(UNIT(p), UNIT_BEFORE,
-                                        SPECIAL_PATHS_TARGET, NULL, true);
+        if (!UNIT(p)->default_dependencies)
+                return 0;
+
+        r = unit_add_dependency_by_name(UNIT(p), UNIT_BEFORE, SPECIAL_PATHS_TARGET, NULL, true);
         if (r < 0)
                 return r;
 
         if (UNIT(p)->manager->running_as == MANAGER_SYSTEM) {
-                r = unit_add_two_dependencies_by_name(UNIT(p), UNIT_AFTER, UNIT_REQUIRES,
-                                                      SPECIAL_SYSINIT_TARGET, NULL, true);
+                r = unit_add_two_dependencies_by_name(UNIT(p), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SYSINIT_TARGET, NULL, true);
                 if (r < 0)
                         return r;
         }
 
-        return unit_add_two_dependencies_by_name(UNIT(p), UNIT_BEFORE, UNIT_CONFLICTS,
-                                                 SPECIAL_SHUTDOWN_TARGET, NULL, true);
+        return unit_add_two_dependencies_by_name(UNIT(p), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true);
 }
 
 static int path_load(Unit *u) {
@@ -360,11 +360,9 @@ static int path_load(Unit *u) {
                 if (r < 0)
                         return r;
 
-                if (UNIT(p)->default_dependencies) {
-                        r = path_add_default_dependencies(p);
-                        if (r < 0)
-                                return r;
-                }
+                r = path_add_default_dependencies(p);
+                if (r < 0)
+                        return r;
         }
 
         return path_verify(p);
diff --git a/src/core/scope.c b/src/core/scope.c
index 8d6149aab0..5f6527c155 100644
--- a/src/core/scope.c
+++ b/src/core/scope.c
@@ -122,6 +122,9 @@ static int scope_add_default_dependencies(Scope *s) {
 
         assert(s);
 
+        if (!UNIT(s)->default_dependencies)
+                return 0;
+
         /* Make sure scopes are unloaded on shutdown */
         r = unit_add_two_dependencies_by_name(
                         UNIT(s),
@@ -173,11 +176,9 @@ static int scope_load(Unit *u) {
         if (r < 0)
                 return r;
 
-        if (u->default_dependencies) {
-                r = scope_add_default_dependencies(s);
-                if (r < 0)
-                        return r;
-        }
+        r = scope_add_default_dependencies(s);
+        if (r < 0)
+                return r;
 
         return scope_verify(s);
 }
diff --git a/src/core/service.c b/src/core/service.c
index 74bbadd3ff..e9d259b84f 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -515,15 +515,38 @@ static int service_add_default_dependencies(Service *s) {
 
         assert(s);
 
+        if (!UNIT(s)->default_dependencies)
+                return 0;
+
         /* Add a number of automatic dependencies useful for the
          * majority of services. */
 
-        /* First, pull in base system */
-        r = unit_add_two_dependencies_by_name(UNIT(s), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_BASIC_TARGET, NULL, true);
+        if (UNIT(s)->manager->running_as == MANAGER_SYSTEM) {
+                /* First, pull in the really early boot stuff, and
+                 * require it, so that we fail if we can't acquire
+                 * it. */
+
+                r = unit_add_two_dependencies_by_name(UNIT(s), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SYSINIT_TARGET, NULL, true);
+                if (r < 0)
+                        return r;
+        } else {
+
+                /* In the --user instance there's no sysinit.target,
+                 * in that case require basic.target instead. */
+
+                r = unit_add_dependency_by_name(UNIT(s), UNIT_REQUIRES, SPECIAL_BASIC_TARGET, NULL, true);
+                if (r < 0)
+                        return r;
+        }
+
+        /* Second, if the rest of the base system is in the same
+         * transaction, order us after it, but do not pull it in or
+         * even require it. */
+        r = unit_add_dependency_by_name(UNIT(s), UNIT_AFTER, SPECIAL_BASIC_TARGET, NULL, true);
         if (r < 0)
                 return r;
 
-        /* Second, activate normal shutdown */
+        /* Third, add us in for normal shutdown. */
         return unit_add_two_dependencies_by_name(UNIT(s), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true);
 }
 
@@ -545,6 +568,43 @@ static void service_fix_output(Service *s) {
                 s->exec_context.std_output = UNIT(s)->manager->default_std_output;
 }
 
+static int service_setup_bus_name(Service *s) {
+        int r;
+
+        assert(s);
+
+        if (!s->bus_name)
+                return 0;
+
+        if (is_kdbus_available()) {
+                const char *n;
+
+                n = strjoina(s->bus_name, ".busname");
+                r = unit_add_dependency_by_name(UNIT(s), UNIT_AFTER, n, NULL, true);
+                if (r < 0)
+                        return log_unit_error_errno(UNIT(s), r, "Failed to add dependency to .busname unit: %m");
+
+        } else {
+                /* If kdbus is not available, we know the dbus socket is required, hence pull it in, and require it */
+                r = unit_add_dependency_by_name(UNIT(s), UNIT_REQUIRES, SPECIAL_DBUS_SOCKET, NULL, true);
+                if (r < 0)
+                        return log_unit_error_errno(UNIT(s), r, "Failed to add dependency on " SPECIAL_DBUS_SOCKET ": %m");
+        }
+
+        /* Regardless if kdbus is used or not, we always want to be ordered against dbus.socket if both are in the transaction. */
+        r = unit_add_dependency_by_name(UNIT(s), UNIT_AFTER, SPECIAL_DBUS_SOCKET, NULL, true);
+        if (r < 0)
+                return log_unit_error_errno(UNIT(s), r, "Failed to add depdendency on " SPECIAL_DBUS_SOCKET ": %m");
+
+        r = unit_watch_bus_name(UNIT(s), s->bus_name);
+        if (r == -EEXIST)
+                return log_unit_error_errno(UNIT(s), r, "Two services allocated for the same bus name %s, refusing operation.", s->bus_name);
+        if (r < 0)
+                return log_unit_error_errno(UNIT(s), r, "Cannot watch bus name %s: %m", s->bus_name);
+
+        return 0;
+}
+
 static int service_add_extras(Service *s) {
         int r;
 
@@ -584,26 +644,13 @@ static int service_add_extras(Service *s) {
         if (s->watchdog_usec > 0 && s->notify_access == NOTIFY_NONE)
                 s->notify_access = NOTIFY_MAIN;
 
-        if (s->bus_name) {
-                const char *n;
-
-                n = strjoina(s->bus_name, ".busname");
-                r = unit_add_dependency_by_name(UNIT(s), UNIT_AFTER, n, NULL, true);
-                if (r < 0)
-                        return r;
-
-                r = unit_watch_bus_name(UNIT(s), s->bus_name);
-                if (r == -EEXIST)
-                        return log_unit_error_errno(UNIT(s), r, "Two services allocated for the same bus name %s, refusing operation.", s->bus_name);
-                if (r < 0)
-                        return log_unit_error_errno(UNIT(s), r, "Cannot watch bus name %s: %m", s->bus_name);
-        }
+        r = service_add_default_dependencies(s);
+        if (r < 0)
+                return r;
 
-        if (UNIT(s)->default_dependencies) {
-                r = service_add_default_dependencies(s);
-                if (r < 0)
-                        return r;
-        }
+        r = service_setup_bus_name(s);
+        if (r < 0)
+                return r;
 
         return 0;
 }
diff --git a/src/core/slice.c b/src/core/slice.c
index 2aa3fbf8be..39dabae055 100644
--- a/src/core/slice.c
+++ b/src/core/slice.c
@@ -85,6 +85,9 @@ static int slice_add_default_dependencies(Slice *s) {
 
         assert(s);
 
+        if (!UNIT(s)->default_dependencies)
+                return 0;
+
         /* Make sure slices are unloaded on shutdown */
         r = unit_add_two_dependencies_by_name(
                         UNIT(s),
@@ -96,7 +99,6 @@ static int slice_add_default_dependencies(Slice *s) {
         return 0;
 }
 
-
 static int slice_verify(Slice *s) {
         _cleanup_free_ char *parent = NULL;
         int r;
@@ -144,11 +146,9 @@ static int slice_load(Unit *u) {
                 if (r < 0)
                         return r;
 
-                if (u->default_dependencies) {
-                        r = slice_add_default_dependencies(s);
-                        if (r < 0)
-                                return r;
-                }
+                r = slice_add_default_dependencies(s);
+                if (r < 0)
+                        return r;
         }
 
         return slice_verify(s);
diff --git a/src/core/socket.c b/src/core/socket.c
index c73ee78b13..43d4ec5dca 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -296,6 +296,9 @@ static int socket_add_default_dependencies(Socket *s) {
         int r;
         assert(s);
 
+        if (!UNIT(s)->default_dependencies)
+                return 0;
+
         r = unit_add_dependency_by_name(UNIT(s), UNIT_BEFORE, SPECIAL_SOCKETS_TARGET, NULL, true);
         if (r < 0)
                 return r;
@@ -365,11 +368,9 @@ static int socket_add_extras(Socket *s) {
                         return r;
         }
 
-        if (u->default_dependencies) {
-                r = socket_add_default_dependencies(s);
-                if (r < 0)
-                        return r;
-        }
+        r = socket_add_default_dependencies(s);
+        if (r < 0)
+                return r;
 
         return 0;
 }
diff --git a/src/core/swap.c b/src/core/swap.c
index e44cffc2e8..ee0838e676 100644
--- a/src/core/swap.c
+++ b/src/core/swap.c
@@ -213,6 +213,9 @@ static int swap_add_device_links(Swap *s) {
 static int swap_add_default_dependencies(Swap *s) {
         assert(s);
 
+        if (!UNIT(s)->default_dependencies)
+                return 0;
+
         if (UNIT(s)->manager->running_as != MANAGER_SYSTEM)
                 return 0;
 
@@ -331,11 +334,9 @@ static int swap_load(Unit *u) {
                 if (r < 0)
                         return r;
 
-                if (UNIT(s)->default_dependencies) {
-                        r = swap_add_default_dependencies(s);
-                        if (r < 0)
-                                return r;
-                }
+                r = swap_add_default_dependencies(s);
+                if (r < 0)
+                        return r;
         }
 
         return swap_verify(s);
diff --git a/src/core/timer.c b/src/core/timer.c
index c9dc97d4fb..06a6035315 100644
--- a/src/core/timer.c
+++ b/src/core/timer.c
@@ -102,6 +102,9 @@ static int timer_add_default_dependencies(Timer *t) {
 
         assert(t);
 
+        if (!UNIT(t)->default_dependencies)
+                return 0;
+
         r = unit_add_dependency_by_name(UNIT(t), UNIT_BEFORE, SPECIAL_TIMERS_TARGET, NULL, true);
         if (r < 0)
                 return r;
@@ -192,11 +195,9 @@ static int timer_load(Unit *u) {
                 if (r < 0)
                         return r;
 
-                if (u->default_dependencies) {
-                        r = timer_add_default_dependencies(t);
-                        if (r < 0)
-                                return r;
-                }
+                r = timer_add_default_dependencies(t);
+                if (r < 0)
+                        return r;
         }
 
         return timer_verify(t);
@@ -518,7 +519,7 @@ static void timer_enter_running(Timer *t) {
         dual_timestamp_get(&t->last_trigger);
 
         if (t->stamp_path)
-                touch_file(t->stamp_path, true, t->last_trigger.realtime, UID_INVALID, GID_INVALID, 0);
+                touch_file(t->stamp_path, true, t->last_trigger.realtime, UID_INVALID, GID_INVALID, MODE_INVALID);
 
         timer_set_state(t, TIMER_RUNNING);
         return;
@@ -554,7 +555,7 @@ static int timer_start(Unit *u) {
                         /* The timer has never run before,
                          * make sure a stamp file exists.
                          */
-                        touch_file(t->stamp_path, true, USEC_INFINITY, UID_INVALID, GID_INVALID, 0);
+                        touch_file(t->stamp_path, true, USEC_INFINITY, UID_INVALID, GID_INVALID, MODE_INVALID);
         }
 
         t->result = TIMER_SUCCESS;