task_save_handler - rewrite code - put string on stack instead

of heap, avoid using strlcat

tasks/task_save.c

@@ -54,12 +54,12 @@
    read/write is a possible suspend to JS code */
 #define SAVE_STATE_CHUNK 4096 * 4096
 #else
-/* A low common denominator write chunk size.  On a slow 
+/* A low common denominator write chunk size.  On a slow
-  (speed class 6) SD card, we can write 6MB/s.  That gives us 
+  (speed class 6) SD card, we can write 6MB/s.  That gives us
-  roughly 100KB/frame.  
+  roughly 100KB/frame.
-  This means we can write savestates with one syscall for cores 
+  This means we can write savestates with one syscall for cores
-  with less than 100KB of state. Class 10 is the standard now 
+  with less than 100KB of state. Class 10 is the standard now
-  even for lousy cards and supports 10MB/s, so you may prefer 
+  even for lousy cards and supports 10MB/s, so you may prefer
   to put this to 170KB. This all assumes that task_save's loop
   is iterated once per frame at 60 FPS; if it's updated less
   frequently this number could be doubled or quadrupled depending
@@ -537,8 +537,7 @@ static void task_save_handler(retro_task_t *task)
 
    if (task_get_cancelled(task) || written != remaining)
    {
-      size_t err_size = 8192 * sizeof(char);
+      char msg[PATH_MAX_LENGTH];
-      char *err       = (char*)malloc(err_size);
 
       if (state->flags & SAVE_TASK_FLAG_UNDO_SAVE)
       {
@@ -546,21 +545,19 @@ static void task_save_handler(retro_task_t *task)
                MSG_FAILED_TO_UNDO_SAVE_STATE);
          RARCH_ERR("[State]: %s \"%s\".\n", failed_undo_str,
                undo_save_buf.path);
-         err[0]      = '\0';
+         snprintf(msg, sizeof(msg), "%s \"RAM\".", failed_undo_str);
-         snprintf(err, err_size - 1, "%s \"RAM\".", failed_undo_str);
       }
       else
       {
-         size_t _len = strlcpy(err,
+         size_t _len = strlcpy(msg,
                msg_hash_to_str(MSG_FAILED_TO_SAVE_STATE_TO),
-               err_size - 1);
+               sizeof(msg));
-         err[  _len] = ' ';
+         msg[  _len] = ' ';
-         err[++_len] = '\0';
+         msg[++_len] = '\0';
-         strlcat(err, state->path, err_size - 1);
+         strlcpy(msg + _len, state->path, sizeof(msg) - _len);
       }
 
-      task_set_error(task, strdup(err));
+      task_set_error(task, strdup(msg));
-      free(err);
       task_save_handler_finished(task, state);
       return;
    }