core: rework reboot parameter logic a bit

Always warn if something fails, and clarify that the involved utility functions
do so in their name.

Drop the REBOOT_PARAM_FILE macro. We don't do this for other flag file paths
like this, so don't do this for this one either. The path isn't configurable
anyway, hence let's make this easier to read by avoiding this one indirection.

1 files changed, 17 insertions, 9 deletions

diff --git a/src/basic/util.c b/src/basic/util.c
index 6996527ec4..957b0e1ff1 100644
--- a/src/basic/util.c
+++ b/src/basic/util.c
@@ -778,16 +778,24 @@ uint64_t physical_memory(void) {
         return (uint64_t) mem * (uint64_t) page_size();
 }
 
-int update_reboot_param_file(const char *param) {
-        int r = 0;
+int update_reboot_parameter_and_warn(const char *param) {
+        int r;
 
-        if (param) {
-                RUN_WITH_UMASK(0022)
-                        r = write_string_file(REBOOT_PARAM_FILE, param, WRITE_STRING_FILE_CREATE);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to write reboot param to "REBOOT_PARAM_FILE": %m");
-        } else
-                (void) unlink(REBOOT_PARAM_FILE);
+        if (isempty(param)) {
+                if (unlink("/run/systemd/reboot-param") < 0) {
+                        if (errno == ENOENT)
+                                return 0;
+
+                        return log_warning_errno(errno, "Failed to unlink reboot parameter file: %m");
+                }
+
+                return 0;
+        }
+
+        RUN_WITH_UMASK(0022)
+                r = write_string_file("/run/systemd/reboot-param", param, WRITE_STRING_FILE_CREATE);
+        if (r < 0)
+                return log_warning_errno(r, "Failed to write reboot parameter file: %m");
 
         return 0;
 }