subsystem part 3: fix saves

CHANGES.md

@@ -48,6 +48,7 @@
 - SHADERS: SPIRV-Cross/slang shader support for D3D11.
 - SHIELD ATV: Allow the remote / gamepad takeover hack to work with the 2017 gamepad
 - SUBSYSTEM: Subsystem saves now respect the save directory
+- SUBSYSTEM: You can now load subsystem games from the menu (see https://github.com/libretro/RetroArch/pull/6282 for caveats)
 - VULKAN: Fix swapchain recreation bug on Nvidia GPUs with Windows 10 (resolved in Windows Nvidia driver version 390.77).
 - WINDOWS: Improved Unicode support (for cores/directory creation and 7zip archives).
 - WINDOWS: Show progress meter on taskbar for downloads (Windows 7 and up).

command.c

@@ -1219,6 +1219,8 @@ static bool event_init_content(void)
    if (rarch_ctl(RARCH_CTL_IS_DUMMY_CORE, NULL))
       return true;
 
+   content_set_subsystem_info();
+
    if (!contentless)
       path_fill_names();
 

content.h

@@ -100,6 +100,9 @@ void content_add_subsystem(const char* path);
 /* Get the current subsystem rom id */
 int content_get_subsystem_rom_id();
 
+/* Set environment variables before a subsystem load */
+void content_set_subsystem_info();
+
 
 RETRO_END_DECLS
 

paths.c

@@ -297,7 +297,6 @@ static bool path_init_subsystem(void)
 
    if (!system || path_is_empty(RARCH_PATH_SUBSYSTEM))
       return false;
-
    /* For subsystems, we know exactly which RAM types are supported. */
 
    info = libretro_find_subsystem_info(
@@ -306,7 +305,6 @@ static bool path_init_subsystem(void)
          path_get(RARCH_PATH_SUBSYSTEM));
 
    /* We'll handle this error gracefully later. */
-
    if (info)
    {
       unsigned num_content = MIN(info->num_roms,

tasks/task_content.c

@@ -285,7 +285,7 @@ static bool content_load(content_ctx_info_t *info)
 
    if (pending_subsystem_init)
    {
-      content_init();
+      command_event(CMD_EVENT_CORE_INIT, NULL);
       content_clear_subsystem();
    }
 
@@ -1834,9 +1834,8 @@ void content_deinit(void)
    core_does_not_need_content = false;
 }
 
-/* Initializes and loads a content file for the currently
- * selected libretro core. */
-bool content_init(void)
+/* Set environment variables before a subsystem load */
+void content_set_subsystem_info()
 {
    if (pending_subsystem_init)
    {
@@ -1845,6 +1844,12 @@ bool content_init(void)
       /* hardcoded to 2 for testing please fix */
       path_set_special(roms, pending_subsystem_rom_num);
    }
+}
+
+/* Initializes and loads a content file for the currently
+ * selected libretro core. */
+bool content_init(void)
+{
    content_information_ctx_t content_ctx;
 
    bool ret                                   = true;