Add debug function/macro, derived from warn

common/util.c

@@ -73,6 +73,19 @@ _warn(int line, const char *fct, const char *fmt, ...)
     fprintf(stderr, "\n");
 }
 
+/** Print debug message on stderr.
+ */
+void
+_debug(int line, const char *fct, const char *fmt, ...)
+{
+    va_list ap;
+    va_start(ap, fmt);
+    fprintf(stderr, "D: awesome: %s:%d: ", fct, line);
+    vfprintf(stderr, fmt, ap);
+    va_end(ap);
+    fprintf(stderr, "\n");
+}
+
 /** \brief safe limited strcpy.
  *
  * Copies at most min(<tt>n-1</tt>, \c l) characters from \c src into \c dst,

common/util.h

@@ -321,6 +321,12 @@ void _warn(int, const char *, const char *, ...)
 
 const char *a_current_time_str(void);
 
+#define debug(string, ...) _debug(__LINE__, \
+                                 __FUNCTION__, \
+                                 string, ## __VA_ARGS__)
+void _debug(int, const char *, const char *, ...)
+    __attribute__ ((format(printf, 3, 4)));
+
 void a_exec(const char *);
 
 #endif