Merge pull request #27212 from DaanDeMeyer/notify-exit

core: Propagate exit status via notify socket when running in VM

man/sd_notify.xml

@@ -170,6 +170,13 @@
         <literal>BUSERROR=org.freedesktop.DBus.Error.TimedOut</literal></para></listitem>
       </varlistentry>
 
+      <varlistentry>
+        <term>EXIT_STATUS=…</term>
+
+        <listitem><para>If a service exits, the return value of its <function>main()</function> function.
+        </para></listitem>
+      </varlistentry>
+
       <varlistentry>
         <term>MAINPID=…</term>
 

src/core/main.c

@@ -3096,6 +3096,9 @@ finish:
         __lsan_do_leak_check();
 #endif
 
+        if (r < 0)
+                (void) sd_notifyf(0, "ERRNO=%i", -r);
+
         /* Try to invoke the shutdown binary unless we already failed.
          * If we failed above, we want to freeze after finishing cleanup. */
         if (arg_runtime_scope == RUNTIME_SCOPE_SYSTEM &&
@@ -3105,6 +3108,10 @@ finish:
                 error_message = "Failed to execute shutdown binary";
         }
 
+        /* This is primarily useful when running systemd in a VM, as it provides the user running the VM with
+         * a mechanism to pick up systemd's exit status in the VM. */
+        (void) sd_notifyf(0, "EXIT_STATUS=%i", retval);
+
         watchdog_free_device();
         arg_watchdog_device = mfree(arg_watchdog_device);
 

src/shared/main-func.h

@@ -21,6 +21,7 @@
                 r = impl;                                               \
                 if (r < 0)                                              \
                         (void) sd_notifyf(0, "ERRNO=%i", -r);           \
+                (void) sd_notifyf(0, "EXIT_STATUS=%i", ret);            \
                 ask_password_agent_close();                             \
                 polkit_agent_close();                                   \
                 pager_close();                                          \

src/shutdown/shutdown.c

@@ -14,6 +14,8 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
+#include "sd-daemon.h"
+
 #include "alloc-util.h"
 #include "async.h"
 #include "binfmt-util.h"
@@ -570,6 +572,10 @@ int main(int argc, char *argv[]) {
         if (!in_container)
                 sync_with_progress();
 
+        /* This is primarily useful when running systemd in a VM, as it provides the user running the VM with
+         * a mechanism to pick up systemd's exit status in the VM. */
+        (void) sd_notifyf(0, "EXIT_STATUS=%i", arg_exit_code);
+
         if (streq(arg_verb, "exit")) {
                 if (in_container) {
                         log_info("Exiting container.");