Keep fakelib2 exclusive from global and emulator overlays

README.md

@@ -79,11 +79,11 @@ Supported keys (all optional):
 - `legacy_mount_pfsc=1|0` (outer `.ffpfsc`; `1` selects the version 1.6 mount profile; default: `1`)
 - `nested_pfs_index_cache=1|0` (cache the containing PFS compressed-file index before attaching a nested image in legacy mode; default: `0`; optimized mode always requests it; the old `legacy_gddr5_cache` name remains accepted)
 - `backport_fakelib=1|0` (`1` mounts sandbox `fakelib` overlays for running games; default: `1`)
-- `update_emulators=1|0` (`1` updates all emulators with matching files in a game's own fakelib; default: `1`)
+- `update_emulators=1|0` (`1` updates all emulators with matching files in a game's own fakelib; `fakelib2` is excluded; default: `1`)
 - `emulators_path=<absolute_path>` (folder containing emulator update files; default: `/data/shadowmount/emus`)
 - `auto_update_ampr=1|0` (check for a new `libSceAmpr.sprx` 30 seconds after startup and every four hours; default: `0`)
 - `ampr_update_url=<http_or_https_url>` (AMPR emulator download URL; default: `https://github.com/drakmor/ampr_emu/releases/latest/download/libSceAmpr.sprx`)
-- `global_fakelib=1|0` (`1` enables the global fakelib overlay when the folder exists; default: `1`)
+- `global_fakelib=1|0` (`1` enables the global fakelib overlay when the folder exists; `fakelib2` remains exclusive; default: `1`)
 - `global_fakelib_path=<absolute_path>` (global fakelib folder; default: `/data/shadowmount/fakelib`)
 - `global_fakelib_priority=game|global` (overlay priority when both global and game fakelib exist; default: `game`)
 - `global_fakelib_exclude=<TITLE_ID>` (repeatable; disables the global fakelib overlay for matching titles)
@@ -187,11 +187,11 @@ Backport overlay behavior:
 - The `backports` folder is ignored during normal game scanning.
 - A backport is applied automatically to the matching mounted game from any configured scan path.
 - If multiple scan paths provide the same title backport, the game's own scan path wins; otherwise scan path order is used.
-- ShadowMount+ checks the selected backport for `fakelib2` and then `fakelib`; if neither exists, it uses only `fakelib` from the original game source. The selected directory is mounted into the running game's sandbox `common/lib`.
-- If `update_emulators=1`, matching files from `emulators_path` replace files in the selected game fakelib. The cache is refreshed when its sources change and expires after seven days without a game launch.
+- ShadowMount+ checks the selected backport for `fakelib2` and then `fakelib`; if neither exists, it uses only `fakelib` from the original game source. The selected directory is mounted into the running game's sandbox `common/lib`. A backport `fakelib2` is always mounted directly and exclusively: neither emulator updates nor the global fakelib can replace or supplement it.
+- If `update_emulators=1`, matching files from `emulators_path` replace files in the selected game fakelib, except when `fakelib2` is selected. The cache is refreshed when its sources change and expires after seven days without a game launch.
 - With `auto_update_ampr=1`, ShadowMount+ checks for AMPR updates 30 seconds after startup and every four hours. It downloads a missing or newer emulator and displays a notification after a successful update.
 - The backport notification adds `Emulators updated` when emulator files are updated for the launched game.
-- If both global and per-game fakelib exist, they are combined in the game cache according to `global_fakelib_priority`. Without a per-game fakelib, the global folder is mounted directly.
+- If both global and per-game fakelib exist, they are combined in the game cache according to `global_fakelib_priority`, unless the selected backport contains `fakelib2`. Without a per-game fakelib, the global folder is mounted directly.
 - Use repeatable `global_fakelib_exclude=<TITLE_ID>` entries to skip the global fakelib for specific games without disabling per-game fakelib.
 - `backport_fakelib=0` disables the sandbox `fakelib` watcher, including global fakelib and emulator updates.
 - For `backport_fakelib` to work correctly, the standalone `BackPork` payload must be disabled. Running both at the same time will conflict.

config.ini.example

@@ -135,7 +135,7 @@
 
 # Updates for multiple emulators in the game fakelib:
 # 1/true/yes/on  -> cache the game's fakelib before launch and replace matching
-#                   cached files from emulators_path
+#                   cached files from emulators_path; fakelib2 is never changed
 # 0/false/no/off -> disable emulator updates
 # Default: 1
 # update_emulators=1
@@ -159,7 +159,8 @@
 # ampr_update_url=https://github.com/drakmor/ampr_emu/releases/latest/download/libSceAmpr.sprx
 
 # Global fakelib overlay:
-# 1/true/yes/on  -> use global fakelib for every tracked game when present
+# 1/true/yes/on  -> use global fakelib for every tracked game when present;
+#                   fakelib2 always remains exclusive when present
 # 0/false/no/off -> do not use the global fakelib folder
 # Default: 1
 # global_fakelib=1

src/sm_fakelib.c

@@ -67,6 +67,12 @@ typedef struct {
   char emulators_path[MAX_PATH];
 } fakelib_cache_context_t;
 
+typedef enum {
+  FAKELIB_SOURCE_NONE = 0,
+  FAKELIB_SOURCE_COMPOSABLE,
+  FAKELIB_SOURCE_FAKELIB2,
+} fakelib_source_kind_t;
+
 static fakelib_session_t g_fakelib_mount;
 static pthread_mutex_t g_fakelib_mutex = PTHREAD_MUTEX_INITIALIZER;
 static pthread_mutex_t g_fakelib_cache_mutex = PTHREAD_MUTEX_INITIALIZER;
@@ -207,7 +213,7 @@ static bool resolve_sandbox_mount_path(const char *title_id,
   return found;
 }
 
-static bool resolve_game_fakelib_source_for_path(
+static fakelib_source_kind_t resolve_game_fakelib_source_for_path(
     const char *title_id, const char *game_path,
     char source_path[MAX_PATH]) {
   source_path[0] = '\0';
@@ -219,10 +225,13 @@ static bool resolve_game_fakelib_source_for_path(
   const struct {
     const char *root;
     const char *directory;
+    fakelib_source_kind_t kind;
   } candidates[] = {
-      {has_backport ? backport_path : NULL, "fakelib2"},
-      {has_backport ? backport_path : NULL, "fakelib"},
-      {has_game ? game_path : NULL, "fakelib"},
+      {has_backport ? backport_path : NULL, "fakelib2",
+       FAKELIB_SOURCE_FAKELIB2},
+      {has_backport ? backport_path : NULL, "fakelib",
+       FAKELIB_SOURCE_COMPOSABLE},
+      {has_game ? game_path : NULL, "fakelib", FAKELIB_SOURCE_COMPOSABLE},
   };
   struct stat st;
   for (size_t i = 0; i < sizeof(candidates) / sizeof(candidates[0]); ++i) {
@@ -232,16 +241,17 @@ static bool resolve_game_fakelib_source_for_path(
                            candidates[i].root, candidates[i].directory);
     if (written > 0 && (size_t)written < MAX_PATH &&
         stat(source_path, &st) == 0 && S_ISDIR(st.st_mode)) {
-      return true;
+      return candidates[i].kind;
     }
   }
 
   source_path[0] = '\0';
-  return false;
+  return FAKELIB_SOURCE_NONE;
 }
 
-static bool resolve_game_fakelib_source(const char *title_id,
-                                         char source_path[MAX_PATH]) {
+static fakelib_source_kind_t
+resolve_game_fakelib_source(const char *title_id,
+                            char source_path[MAX_PATH]) {
   char game_path[MAX_PATH];
   if (!read_mount_link(title_id, game_path, sizeof(game_path)))
     game_path[0] = '\0';
@@ -994,8 +1004,9 @@ static void prepare_title_cache(const char *title_id, const char *game_path) {
     return;
 
   char game_source_path[MAX_PATH];
-  if (!resolve_game_fakelib_source_for_path(title_id, game_path,
-                                             game_source_path)) {
+  fakelib_source_kind_t source_kind = resolve_game_fakelib_source_for_path(
+      title_id, game_path, game_source_path);
+  if (source_kind != FAKELIB_SOURCE_COMPOSABLE) {
     remove_title_cache(title_id);
     return;
   }
@@ -1151,12 +1162,16 @@ void sm_fakelib_game_on_exec(pid_t pid, const char *title_id,
     }
   }
 
-  char game_source_path[MAX_PATH];
-  char global_source_path[MAX_PATH];
-  char mount_path[MAX_PATH];
-  bool has_game = resolve_game_fakelib_source(title_id, game_source_path);
-  bool has_global =
-      resolve_global_fakelib_source(title_id, global_source_path);
+  char game_source_path[MAX_PATH] = {0};
+  char global_source_path[MAX_PATH] = {0};
+  char mount_path[MAX_PATH] = {0};
+  fakelib_source_kind_t source_kind =
+      resolve_game_fakelib_source(title_id, game_source_path);
+  bool has_game = source_kind != FAKELIB_SOURCE_NONE;
+  bool allows_composition = source_kind != FAKELIB_SOURCE_FAKELIB2;
+  bool has_global = allows_composition &&
+                    resolve_global_fakelib_source(title_id,
+                                                  global_source_path);
   if (!has_global && !has_game) {
     pthread_mutex_unlock(&g_fakelib_mutex);
     return;
@@ -1168,7 +1183,7 @@ void sm_fakelib_game_on_exec(pid_t pid, const char *title_id,
   size_t emulator_file_count = 0;
   bool cache_resolved = false;
   bool cache_includes_global = false;
-  if (has_game) {
+  if (source_kind == FAKELIB_SOURCE_COMPOSABLE) {
     char cache_path[MAX_PATH];
     cache_resolved = resolve_cached_fakelib(
         title_id, game_source_path, cache_path, &emulator_file_count,
@@ -1198,7 +1213,9 @@ void sm_fakelib_game_on_exec(pid_t pid, const char *title_id,
                 sizeof(g_fakelib_mount.mount_path));
 
   const char *source_path = has_game ? game_source_path : global_source_path;
-  const char *label = has_game ? "game" : "global";
+  const char *label = !allows_composition
+                          ? "fakelib2"
+                          : (has_game ? "game" : "global");
   if (!track_fakelib_overlay(title_id, source_path, mount_path, label)) {
     (void)cleanup_fakelib_mount();
     pthread_mutex_unlock(&g_fakelib_mutex);