core: remember first unit failure, not last unit failure

Previously, the result value of a unit was overriden with each failure that
took place, so that the result always reported the last failure that took
place.

With this commit this is changed, so that the first failure taking place is
stored instead. This should normally not matter much as multiple failures are
sufficiently uncommon. However, it improves one behaviour: if we send SIGABRT
to a service due to a watchdog timeout, then this currently would be reported
as "coredump" failure, rather than the "watchodg" failure it really is. Hence,
in order to report information about the type of the failure, and not about
the effect of it, let's change this from all unit type to store the first, not
the last failure.

This addresses the issue pointed out here:

https://github.com/systemd/systemd/pull/3818#discussion_r73433520

9 files changed, 28 insertions, 28 deletions

diff --git a/src/core/automount.c b/src/core/automount.c
index 20a73c76f9..00295cf769 100644
--- a/src/core/automount.c
+++ b/src/core/automount.c
@@ -301,7 +301,7 @@ static void automount_dump(Unit *u, FILE *f, const char *prefix) {
 static void automount_enter_dead(Automount *a, AutomountResult f) {
         assert(a);
 
-        if (f != AUTOMOUNT_SUCCESS)
+        if (a->result == AUTOMOUNT_SUCCESS)
                 a->result = f;
 
         automount_set_state(a, a->result != AUTOMOUNT_SUCCESS ? AUTOMOUNT_FAILED : AUTOMOUNT_DEAD);
diff --git a/src/core/busname.c b/src/core/busname.c
index 730be2ee14..7952cd31aa 100644
--- a/src/core/busname.c
+++ b/src/core/busname.c
@@ -442,7 +442,7 @@ fail:
 static void busname_enter_dead(BusName *n, BusNameResult f) {
         assert(n);
 
-        if (f != BUSNAME_SUCCESS)
+        if (n->result == BUSNAME_SUCCESS)
                 n->result = f;
 
         busname_set_state(n, n->result != BUSNAME_SUCCESS ? BUSNAME_FAILED : BUSNAME_DEAD);
@@ -454,7 +454,7 @@ static void busname_enter_signal(BusName *n, BusNameState state, BusNameResult f
 
         assert(n);
 
-        if (f != BUSNAME_SUCCESS)
+        if (n->result == BUSNAME_SUCCESS)
                 n->result = f;
 
         kill_context_init(&kill_context);
@@ -882,7 +882,7 @@ static void busname_sigchld_event(Unit *u, pid_t pid, int code, int status) {
         log_unit_full(u, f == BUSNAME_SUCCESS ? LOG_DEBUG : LOG_NOTICE, 0,
                       "Control process exited, code=%s status=%i", sigchld_code_to_string(code), status);
 
-        if (f != BUSNAME_SUCCESS)
+        if (n->result == BUSNAME_SUCCESS)
                 n->result = f;
 
         switch (n->state) {
diff --git a/src/core/mount.c b/src/core/mount.c
index 3f6ac7fcf9..f3ccf6d48a 100644
--- a/src/core/mount.c
+++ b/src/core/mount.c
@@ -759,7 +759,7 @@ static int mount_spawn(Mount *m, ExecCommand *c, pid_t *_pid) {
 static void mount_enter_dead(Mount *m, MountResult f) {
         assert(m);
 
-        if (f != MOUNT_SUCCESS)
+        if (m->result == MOUNT_SUCCESS)
                 m->result = f;
 
         mount_set_state(m, m->result != MOUNT_SUCCESS ? MOUNT_FAILED : MOUNT_DEAD);
@@ -775,7 +775,7 @@ static void mount_enter_dead(Mount *m, MountResult f) {
 static void mount_enter_mounted(Mount *m, MountResult f) {
         assert(m);
 
-        if (f != MOUNT_SUCCESS)
+        if (m->result == MOUNT_SUCCESS)
                 m->result = f;
 
         mount_set_state(m, MOUNT_MOUNTED);
@@ -786,7 +786,7 @@ static void mount_enter_signal(Mount *m, MountState state, MountResult f) {
 
         assert(m);
 
-        if (f != MOUNT_SUCCESS)
+        if (m->result == MOUNT_SUCCESS)
                 m->result = f;
 
         r = unit_kill_context(
@@ -1158,7 +1158,7 @@ static void mount_sigchld_event(Unit *u, pid_t pid, int code, int status) {
         else
                 assert_not_reached("Unknown code");
 
-        if (f != MOUNT_SUCCESS)
+        if (m->result == MOUNT_SUCCESS)
                 m->result = f;
 
         if (m->control_command) {
diff --git a/src/core/path.c b/src/core/path.c
index 0dd0d375d8..10f9b06974 100644
--- a/src/core/path.c
+++ b/src/core/path.c
@@ -454,7 +454,7 @@ static int path_coldplug(Unit *u) {
 static void path_enter_dead(Path *p, PathResult f) {
         assert(p);
 
-        if (f != PATH_SUCCESS)
+        if (p->result == PATH_SUCCESS)
                 p->result = f;
 
         path_set_state(p, p->result != PATH_SUCCESS ? PATH_FAILED : PATH_DEAD);
diff --git a/src/core/scope.c b/src/core/scope.c
index b45e238974..b278aed3d6 100644
--- a/src/core/scope.c
+++ b/src/core/scope.c
@@ -221,7 +221,7 @@ static void scope_dump(Unit *u, FILE *f, const char *prefix) {
 static void scope_enter_dead(Scope *s, ScopeResult f) {
         assert(s);
 
-        if (f != SCOPE_SUCCESS)
+        if (s->result == SCOPE_SUCCESS)
                 s->result = f;
 
         scope_set_state(s, s->result != SCOPE_SUCCESS ? SCOPE_FAILED : SCOPE_DEAD);
@@ -233,7 +233,7 @@ static void scope_enter_signal(Scope *s, ScopeState state, ScopeResult f) {
 
         assert(s);
 
-        if (f != SCOPE_SUCCESS)
+        if (s->result == SCOPE_SUCCESS)
                 s->result = f;
 
         unit_watch_all_pids(UNIT(s));
diff --git a/src/core/service.c b/src/core/service.c
index 0cbea52276..a6793b813b 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -1423,7 +1423,7 @@ static void service_enter_dead(Service *s, ServiceResult f, bool allow_restart)
         int r;
         assert(s);
 
-        if (f != SERVICE_SUCCESS)
+        if (s->result == SERVICE_SUCCESS)
                 s->result = f;
 
         service_set_state(s, s->result != SERVICE_SUCCESS ? SERVICE_FAILED : SERVICE_DEAD);
@@ -1472,7 +1472,7 @@ static void service_enter_stop_post(Service *s, ServiceResult f) {
         int r;
         assert(s);
 
-        if (f != SERVICE_SUCCESS)
+        if (s->result == SERVICE_SUCCESS)
                 s->result = f;
 
         service_unwatch_control_pid(s);
@@ -1525,7 +1525,7 @@ static void service_enter_signal(Service *s, ServiceState state, ServiceResult f
 
         assert(s);
 
-        if (f != SERVICE_SUCCESS)
+        if (s->result == SERVICE_SUCCESS)
                 s->result = f;
 
         unit_watch_all_pids(UNIT(s));
@@ -1583,7 +1583,7 @@ static void service_enter_stop(Service *s, ServiceResult f) {
 
         assert(s);
 
-        if (f != SERVICE_SUCCESS)
+        if (s->result == SERVICE_SUCCESS)
                 s->result = f;
 
         service_unwatch_control_pid(s);
@@ -1635,7 +1635,7 @@ static bool service_good(Service *s) {
 static void service_enter_running(Service *s, ServiceResult f) {
         assert(s);
 
-        if (f != SERVICE_SUCCESS)
+        if (s->result == SERVICE_SUCCESS)
                 s->result = f;
 
         service_unwatch_control_pid(s);
@@ -2609,7 +2609,7 @@ static void service_sigchld_event(Unit *u, pid_t pid, int code, int status) {
                            "EXIT_STATUS=%i", status,
                            NULL);
 
-                if (f != SERVICE_SUCCESS)
+                if (s->result == SERVICE_SUCCESS)
                         s->result = f;
 
                 if (s->main_command &&
@@ -2690,7 +2690,7 @@ static void service_sigchld_event(Unit *u, pid_t pid, int code, int status) {
                               "Control process exited, code=%s status=%i",
                               sigchld_code_to_string(code), status);
 
-                if (f != SERVICE_SUCCESS)
+                if (s->result == SERVICE_SUCCESS)
                         s->result = f;
 
                 /* Immediately get rid of the cgroup, so that the
diff --git a/src/core/socket.c b/src/core/socket.c
index 82363e2157..c919e89b7d 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -1810,7 +1810,7 @@ fail:
 static void socket_enter_dead(Socket *s, SocketResult f) {
         assert(s);
 
-        if (f != SOCKET_SUCCESS)
+        if (s->result == SOCKET_SUCCESS)
                 s->result = f;
 
         socket_set_state(s, s->result != SOCKET_SUCCESS ? SOCKET_FAILED : SOCKET_DEAD);
@@ -1829,7 +1829,7 @@ static void socket_enter_stop_post(Socket *s, SocketResult f) {
         int r;
         assert(s);
 
-        if (f != SOCKET_SUCCESS)
+        if (s->result == SOCKET_SUCCESS)
                 s->result = f;
 
         socket_unwatch_control_pid(s);
@@ -1857,7 +1857,7 @@ static void socket_enter_signal(Socket *s, SocketState state, SocketResult f) {
 
         assert(s);
 
-        if (f != SOCKET_SUCCESS)
+        if (s->result == SOCKET_SUCCESS)
                 s->result = f;
 
         r = unit_kill_context(
@@ -1901,7 +1901,7 @@ static void socket_enter_stop_pre(Socket *s, SocketResult f) {
         int r;
         assert(s);
 
-        if (f != SOCKET_SUCCESS)
+        if (s->result == SOCKET_SUCCESS)
                 s->result = f;
 
         socket_unwatch_control_pid(s);
@@ -2822,7 +2822,7 @@ static void socket_sigchld_event(Unit *u, pid_t pid, int code, int status) {
                       "Control process exited, code=%s status=%i",
                       sigchld_code_to_string(code), status);
 
-        if (f != SOCKET_SUCCESS)
+        if (s->result == SOCKET_SUCCESS)
                 s->result = f;
 
         if (s->control_command &&
diff --git a/src/core/swap.c b/src/core/swap.c
index 0ba4c4d881..2c802da3b5 100644
--- a/src/core/swap.c
+++ b/src/core/swap.c
@@ -673,7 +673,7 @@ fail:
 static void swap_enter_dead(Swap *s, SwapResult f) {
         assert(s);
 
-        if (f != SWAP_SUCCESS)
+        if (s->result == SWAP_SUCCESS)
                 s->result = f;
 
         swap_set_state(s, s->result != SWAP_SUCCESS ? SWAP_FAILED : SWAP_DEAD);
@@ -689,7 +689,7 @@ static void swap_enter_dead(Swap *s, SwapResult f) {
 static void swap_enter_active(Swap *s, SwapResult f) {
         assert(s);
 
-        if (f != SWAP_SUCCESS)
+        if (s->result == SWAP_SUCCESS)
                 s->result = f;
 
         swap_set_state(s, SWAP_ACTIVE);
@@ -700,7 +700,7 @@ static void swap_enter_signal(Swap *s, SwapState state, SwapResult f) {
 
         assert(s);
 
-        if (f != SWAP_SUCCESS)
+        if (s->result == SWAP_SUCCESS)
                 s->result = f;
 
         r = unit_kill_context(
@@ -997,7 +997,7 @@ static void swap_sigchld_event(Unit *u, pid_t pid, int code, int status) {
         else
                 assert_not_reached("Unknown code");
 
-        if (f != SWAP_SUCCESS)
+        if (s->result == SWAP_SUCCESS)
                 s->result = f;
 
         if (s->control_command) {
diff --git a/src/core/timer.c b/src/core/timer.c
index 3206296f09..e2b43f02f8 100644
--- a/src/core/timer.c
+++ b/src/core/timer.c
@@ -291,7 +291,7 @@ static int timer_coldplug(Unit *u) {
 static void timer_enter_dead(Timer *t, TimerResult f) {
         assert(t);
 
-        if (f != TIMER_SUCCESS)
+        if (t->result == TIMER_SUCCESS)
                 t->result = f;
 
         timer_set_state(t, t->result != TIMER_SUCCESS ? TIMER_FAILED : TIMER_DEAD);