(ovr) start implementing diff function

command.c

@@ -1569,43 +1569,52 @@ static bool command_event_save_core_config(void)
  **/
 void command_event_save_current_config(bool overrides)
 {
-   if (overrides)
-      return;
-
    settings_t *settings = config_get_ptr();
    global_t   *global   = global_get_ptr();
 
-   if (settings->config_save_on_exit && !string_is_empty(global->path.config))
+   if (!overrides)
+   {
+
+      if (settings->config_save_on_exit && !string_is_empty(global->path.config))
+      {
+         bool ret                = false;
+         char msg[128]           = {0};
+         const char *config_path = config_get_active_path();
+
+         /* Save last core-specific config to the default config location,
+          * needed on consoles for core switching and reusing last good
+          * config for new cores.
+          */
+
+         /* Flush out the core specific config. */
+         if (config_path)
+            ret = config_save_file(config_path);
+
+         if (ret)
+         {
+            snprintf(msg, sizeof(msg), "%s \"%s\".",
+                  msg_hash_to_str(MSG_SAVED_NEW_CONFIG_TO),
+                  global->path.config);
+            RARCH_LOG("%s\n", msg);
+         }
+         else
+         {
+            snprintf(msg, sizeof(msg), "%s \"%s\".",
+                  msg_hash_to_str(MSG_FAILED_SAVING_CONFIG_TO),
+                  global->path.config);
+            RARCH_ERR("%s\n", msg);
+         }
+
+         runloop_msg_queue_push(msg, 1, 180, true);
+      }
+   }
+   else
    {
       bool ret                = false;
       char msg[128]           = {0};
-      const char *config_path = config_get_active_path();
 
-      /* Save last core-specific config to the default config location,
-       * needed on consoles for core switching and reusing last good
-       * config for new cores.
-       */
-
-      /* Flush out the core specific config. */
-      if (config_path)
-         ret = config_save_file(config_path);
-
-      if (ret)
-      {
-         snprintf(msg, sizeof(msg), "%s \"%s\".",
-               msg_hash_to_str(MSG_SAVED_NEW_CONFIG_TO),
-               global->path.config);
-         RARCH_LOG("%s\n", msg);
-      }
-      else
-      {
-         snprintf(msg, sizeof(msg), "%s \"%s\".",
-               msg_hash_to_str(MSG_FAILED_SAVING_CONFIG_TO),
-               global->path.config);
-         RARCH_ERR("%s\n", msg);
-      }
-
-      runloop_msg_queue_push(msg, 1, 180, true);
+      ret = config_save_file_diff();
+      return;
    }
 }
 

configuration.c

@@ -1294,9 +1294,10 @@ static bool config_load_file(const char *path, bool set_defaults,
    char tmp_append_path[PATH_MAX_LENGTH] = {0}; /* Don't destroy append_config_path. */
    unsigned msg_color                    = 0;
    config_file_t *conf                   = NULL;
+   global_t   *global                    = global_get_ptr();
+
    if (!settings)
       settings = config_get_ptr();
-   global_t   *global                    = global_get_ptr();
 
    struct config_bool_setting_ptr bool_settings[] = {
       { "video_windowed_fullscreen",   &settings->video.windowed_fullscreen},
@@ -2221,7 +2222,7 @@ bool config_load_override(void)
    /* Reset save paths. */
    retroarch_override_setting_set(RARCH_OVERRIDE_SETTING_STATE_PATH);
    retroarch_override_setting_set(RARCH_OVERRIDE_SETTING_SAVE_PATH);
-
+   global->path.append_config[0] = '\0';
    return true;
 }
 
@@ -3314,6 +3315,33 @@ bool config_save_file(const char *path)
    return ret;
 }
 
+/**
+ * config_save_file:
+ * @path            : Path that shall be written to.
+ *
+ * Writes a config file to disk.
+ *
+ * Returns: true (1) on success, otherwise returns false (0).
+ **/
+bool config_save_file_diff()
+{
+   unsigned i           = 0;
+   bool ret             = false;
+   settings_t *settings = config_get_ptr();
+   settings_t *orig     = (settings_t*)calloc(1, sizeof(settings_t));
+   global_t   *global   = global_get_ptr();
+
+   /* Load the original config file in memory */
+   config_load_file(global->path.config, false, orig);
+
+   /* Test to compare with a well known setting */
+   /*RARCH_LOG ("Rewind: %d %d\n", settings->rewind_enable, orig->rewind_enable);
+   RARCH_LOG ("DBG: %d %d\n", settings->debug_panel_enable, orig->cheevos.enable);
+   RARCH_LOG ("FPS: %d %d\n", settings->fps_show, orig->fps_show);
+   RARCH_LOG ("FPS: %s %s\n", settings->username, orig->username);*/
+   return false;
+}
+
 /* Replaces currently loaded configuration file with
  * another one. Will load a dummy core to flush state
  * properly. */

configuration.h

@@ -653,6 +653,16 @@ bool config_save_autoconf_profile(const char *path, unsigned user);
  **/
 bool config_save_file(const char *path);
 
+/**
+ * config_save_file_diff:
+ * @path            : Path that shall be written to.
+ *
+ * Writes a config file override to disk.
+ *
+ * Returns: true (1) on success, otherwise returns false (0).
+ **/
+bool config_save_file_diff();
+
 /* Replaces currently loaded configuration file with
  * another one. Will load a dummy core to flush state
  * properly. */