vsnprintf fix

Author: devfacet

src/tl_error.c

@@ -24,21 +24,26 @@ void tl_error_set(TLError *error, TLErrorCode code, const char *message, ...) {
     // Set message if provided
     if (message) {
         va_list args;
+        va_list args_copy;
+
         va_start(args, message);
-        int size = vsnprintf(NULL, 0, message, args);
-        va_end(args);
+        va_copy(args_copy, args);
+
+        int size = vsnprintf(NULL, 0, message, args_copy);
+        va_end(args_copy);
 
         if (size < 0) {
+            va_end(args);
             return; // ignore if vsnprintf fails
         }
 
-        error->message = malloc(size + 1); // include null terminator by adding 1
+        error->message_size = (size_t)size + 1;
+        error->message = malloc(error->message_size); // include null terminator by adding 1
         if (!error->message) {
+            va_end(args);
             return; // ignore if malloc fails
         }
-        error->message_size = size + 1;
 
-        va_start(args, message);
         vsnprintf((char *)error->message, error->message_size, message, args);
         va_end(args);
     }