Merge pull request #20233 from maanyagoenka/log-error

systemd-analyze: add option to return an error value when unit verification fails

src/basic/log.c

@@ -39,6 +39,9 @@
 
 #define SNDBUF_SIZE (8*1024*1024)
 
+static log_syntax_callback_t log_syntax_callback = NULL;
+static void *log_syntax_callback_userdata = NULL;
+
 static LogTarget log_target = LOG_TARGET_CONSOLE;
 static int log_max_level = LOG_INFO;
 static int log_facility = LOG_DAEMON;
@@ -1341,6 +1344,14 @@ void log_received_signal(int level, const struct signalfd_siginfo *si) {
                          signal_to_string(si->ssi_signo));
 }
 
+void set_log_syntax_callback(log_syntax_callback_t cb, void *userdata) {
+        assert(!log_syntax_callback || !cb);
+        assert(!log_syntax_callback_userdata || !userdata);
+
+        log_syntax_callback = cb;
+        log_syntax_callback_userdata = userdata;
+}
+
 int log_syntax_internal(
                 const char *unit,
                 int level,
@@ -1352,6 +1363,9 @@ int log_syntax_internal(
                 const char *func,
                 const char *format, ...) {
 
+        if (log_syntax_callback)
+                log_syntax_callback(unit, level, log_syntax_callback_userdata);
+
         PROTECT_ERRNO;
         char buffer[LINE_MAX];
         va_list ap;

src/basic/log.h

@@ -32,6 +32,15 @@ typedef enum LogTarget{
 #define IS_SYNTHETIC_ERRNO(val)             ((val) >> 30 & 1)
 #define ERRNO_VALUE(val)                    (abs(val) & 255)
 
+/* The callback function to be invoked when syntax warnings are seen
+ * in the unit files. */
+typedef void (*log_syntax_callback_t)(const char *unit, int level, void *userdata);
+void set_log_syntax_callback(log_syntax_callback_t cb, void *userdata);
+
+static inline void clear_log_syntax_callback(dummy_t *dummy) {
+          set_log_syntax_callback(/* cb= */ NULL, /* userdata= */ NULL);
+}
+
 const char *log_target_to_string(LogTarget target) _const_;
 LogTarget log_target_from_string(const char *s) _pure_;
 void log_set_target(LogTarget target);

src/basic/macro.h

@@ -460,4 +460,10 @@ static inline size_t size_add(size_t x, size_t y) {
         return y >= SIZE_MAX - x ? SIZE_MAX : x + y;
 }
 
+typedef struct {
+        int _empty[0];
+} dummy_t;
+
+assert_cc(sizeof(dummy_t) == 0);
+
 #include "log.h"