Merge pull request #8802 from keszybz/errno-reform

Errno reform

src/basic/audit-util.c

@@ -82,10 +82,9 @@ bool use_audit(void) {
                 fd = socket(AF_NETLINK, SOCK_RAW|SOCK_CLOEXEC|SOCK_NONBLOCK, NETLINK_AUDIT);
                 if (fd < 0) {
                         cached_use = !IN_SET(errno, EAFNOSUPPORT, EPROTONOSUPPORT, EPERM);
-                        if (errno == EPERM)
-                                log_debug_errno(errno, "Audit access prohibited, won't talk to audit");
-                }
-                else {
+                        if (!cached_use)
+                                log_debug_errno(errno, "Won't talk to audit: %m");
+                } else {
                         cached_use = true;
                         safe_close(fd);
                 }

src/basic/capability-util.c

@@ -301,8 +301,7 @@ int drop_privileges(uid_t uid, gid_t gid, uint64_t keep_capabilities) {
         if (prctl(PR_SET_KEEPCAPS, 1) < 0)
                 return log_error_errno(errno, "Failed to enable keep capabilities flag: %m");
 
-        r = setresuid(uid, uid, uid);
-        if (r < 0)
+        if (setresuid(uid, uid, uid) < 0)
                 return log_error_errno(errno, "Failed to change user ID: %m");
 
         if (prctl(PR_SET_KEEPCAPS, 0) < 0)

src/basic/log.c

@@ -686,9 +686,8 @@ int log_internalv_realm(
         if (_likely_(LOG_PRI(level) > log_max_level[realm]))
                 return -error;
 
-        /* Make sure that %m maps to the specified error */
-        if (error != 0)
-                errno = error;
+        /* Make sure that %m maps to the specified error (or "Success"). */
+        errno = error;
 
         (void) vsnprintf(buffer, sizeof buffer, format, ap);