player: use XDG_STATE_HOME for watch_later

A pain point for some users is the fact that watch_later is stored in
the ~/.config directory when it's really not configuration data. Roughly
2 years ago, XDG_STATE_DIR was added to the XDG Base Directory
Specification[0] and its description, user-specific state data, actually
perfectly matches what watch_later data is for. Let's go ahead and use
this directory as the default for watch_later. This change only affects
non-darwin unix-like systems (i.e. Linux, BSDs, etc.). The directory
doesn't move for anyone else.

Internally, quite a few things change with regards to the path
selection. If the platform in question does not have a statedir concept,
then the path selection will simply return "home" instead (old
behavior). Fixes #9147.

[0]: 4f2884e16d

DOCS/interface-changes.rst

@@ -61,6 +61,9 @@ Interface changes
       `--gamma` to float.
     - add `platform` property
     - add `--auto-window-resize`
+    - `--save-position-on-quit` and its associated commands now store state files in
+      the XDG_STATE_HOME directory by default. This only has an effect on linux/bsd
+      systems.
  --- mpv 0.35.0 ---
     - add the `--vo=gpu-next` video output driver, as well as the options
       `--allow-delayed-peak-detect`, `--builtin-scalers`,

DOCS/man/mpv.rst

@@ -461,6 +461,8 @@ Name             Meaning
 ``~~desktop/``   the path to the desktop (win32, macOS)
 ``~~exe_dir/``   win32 only: the path to the directory containing the exe (for
                  config file purposes; ``$MPV_HOME`` overrides it)
+``~~state/``     the path to application state data (``~/.local/state/mpv/``)
+                 On some platforms, this will be the same as ``~~home/``.
 ``~~old_home/``  do not use
 ================ ===============================================================
 
@@ -1584,7 +1586,7 @@ For Windows-specifics, see `FILES ON WINDOWS`_ section.
 
     See `Script location`_ for details.
 
-``~/.config/mpv/watch_later/``
+``~/.local/state/mpv/watch_later/``
     Contains temporary config files needed for resuming playback of files with
     the watch later feature. See for example the ``Q`` key binding, or the
     ``quit-watch-later`` input command.

DOCS/man/options.rst

@@ -1015,8 +1015,9 @@ Watch Later
 ``--watch-later-directory=<path>``
     The directory in which to store the "watch later" temporary files.
 
-    The default is a subdirectory named "watch_later" underneath the
-    config directory (usually ``~/.config/mpv/``).
+    If this option is unset, the files will be stored in a subdirectory
+    named "watch_later" underneath the local state directory
+    (usually ``~/.local/state/mpv/``).
 
 ``--no-resume-playback``
     Do not restore playback position from the ``watch_later`` configuration

common/global.h

@@ -10,6 +10,7 @@ struct mpv_global {
     struct mp_client_api *client_api;
     char *configdir;
     struct stats_base *stats;
+    bool no_statedir;
 };
 
 #endif

options/path.c

@@ -65,19 +65,6 @@ static const char *const config_dirs[] = {
     "global",
 };
 
-void mp_init_paths(struct mpv_global *global, struct MPOpts *opts)
-{
-    TA_FREEP(&global->configdir);
-
-    const char *force_configdir = getenv("MPV_HOME");
-    if (opts->force_configdir && opts->force_configdir[0])
-        force_configdir = opts->force_configdir;
-    if (!opts->load_config)
-        force_configdir = "";
-
-    global->configdir = talloc_strdup(global, force_configdir);
-}
-
 // Return a platform specific path using a path type as defined in osdep/path.h.
 // Keep in mind that the only way to free the return value is freeing talloc_ctx
 // (or its children), as this function can return a statically allocated string.
@@ -87,13 +74,19 @@ static const char *mp_get_platform_path(void *talloc_ctx,
 {
     assert(talloc_ctx);
 
-    if (global->configdir) {
+    bool config_dir = strcmp(type, "state") != 0;
+    if (global->configdir && config_dir) {
         for (int n = 0; n < MP_ARRAY_SIZE(config_dirs); n++) {
             if (strcmp(config_dirs[n], type) == 0)
                 return (n == 0 && global->configdir[0]) ? global->configdir : NULL;
         }
     }
 
+    // Return the native config path if the platform doesn't support the
+    // type we are trying to fetch.
+    if (strcmp(type, "state") == 0 && global->no_statedir)
+        type = "home";
+
     for (int n = 0; n < MP_ARRAY_SIZE(path_resolvers); n++) {
         const char *path = path_resolvers[n](talloc_ctx, type);
         if (path && path[0])
@@ -102,6 +95,27 @@ static const char *mp_get_platform_path(void *talloc_ctx,
     return NULL;
 }
 
+void mp_init_paths(struct mpv_global *global, struct MPOpts *opts)
+{
+    TA_FREEP(&global->configdir);
+
+    // Check if the platform has unique directories that differ from
+    // the standard config directory.
+    void *tmp = talloc_new(NULL);
+    const char *state = mp_get_platform_path(tmp, global, "state");
+    if (!state)
+        global->no_statedir = true;
+    talloc_free(tmp);
+
+    const char *force_configdir = getenv("MPV_HOME");
+    if (opts->force_configdir && opts->force_configdir[0])
+        force_configdir = opts->force_configdir;
+    if (!opts->load_config)
+        force_configdir = "";
+
+    global->configdir = talloc_strdup(global, force_configdir);
+}
+
 char *mp_find_user_file(void *talloc_ctx, struct mpv_global *global,
                         const char *type, const char *filename)
 {

osdep/path-unix.c

@@ -27,14 +27,16 @@ static pthread_once_t path_init_once = PTHREAD_ONCE_INIT;
 
 static char mpv_home[512];
 static char old_home[512];
+static char mpv_state[512];
 
 static void path_init(void)
 {
     char *home = getenv("HOME");
-    char *xdg_dir = getenv("XDG_CONFIG_HOME");
+    char *xdg_config = getenv("XDG_CONFIG_HOME");
+    char *xdg_state = getenv("XDG_STATE_HOME");
 
-    if (xdg_dir && xdg_dir[0]) {
-        snprintf(mpv_home, sizeof(mpv_home), "%s/mpv", xdg_dir);
+    if (xdg_config && xdg_config[0]) {
+        snprintf(mpv_home, sizeof(mpv_home), "%s/mpv", xdg_config);
     } else if (home && home[0]) {
         snprintf(mpv_home, sizeof(mpv_home), "%s/.config/mpv", home);
     }
@@ -43,10 +45,17 @@ static void path_init(void)
     if (home && home[0])
         snprintf(old_home, sizeof(old_home), "%s/.mpv", home);
 
+    if (xdg_state && xdg_state[0]) {
+        snprintf(mpv_state, sizeof(mpv_state), "%s/mpv", xdg_state);
+    } else if (home && home[0]) {
+        snprintf(mpv_state, sizeof(mpv_state), "%s/.local/state/mpv", home);
+    }
+
     // If the old ~/.mpv exists, and the XDG config dir doesn't, use the old
-    // config dir only.
+    // config dir only. Also do not use any other XDG directories.
     if (mp_path_exists(old_home) && !mp_path_exists(mpv_home)) {
         snprintf(mpv_home, sizeof(mpv_home), "%s", old_home);
+        snprintf(mpv_state, sizeof(mpv_state), "%s", old_home);
         old_home[0] = '\0';
     }
 }
@@ -58,6 +67,8 @@ const char *mp_get_platform_path_unix(void *talloc_ctx, const char *type)
         return mpv_home;
     if (strcmp(type, "old_home") == 0)
         return old_home;
+    if (strcmp(type, "state") == 0)
+        return mpv_state;
     if (strcmp(type, "global") == 0)
         return MPV_CONFDIR;
     if (strcmp(type, "desktop") == 0)

osdep/path.h

@@ -11,6 +11,12 @@
 //  "global"        the least priority, global config file location
 //  "desktop"       path to desktop contents
 //
+//  These additional types are also defined. However, they are not necessarily
+//  implemented on every platform. Unlike some other type values that are
+//  platform specific (like "osxbundle"), the value of "home" is returned
+//  instead if these types are not explicitly defined.
+//  "state"         the native mpv-specific user state dir
+//
 // It is allowed to return a static string, so the caller must set talloc_ctx
 // to something other than NULL to avoid memory leaks.
 typedef const char *(*mp_get_platform_path_cb)(void *talloc_ctx, const char *type);

player/configfiles.c

@@ -192,6 +192,17 @@ static bool copy_mtime(const char *f1, const char *f2)
     return true;
 }
 
+static char *mp_get_playback_resume_dir(struct MPContext *mpctx)
+{
+    char *wl_dir = mpctx->opts->watch_later_directory;
+    if (wl_dir && wl_dir[0]) {
+        wl_dir = mp_get_user_path(mpctx, mpctx->global, wl_dir);
+    } else {
+        wl_dir = mp_find_user_file(mpctx, mpctx->global, "state", MP_WATCH_LATER_CONF);
+    }
+    return wl_dir;
+}
+
 static char *mp_get_playback_resume_config_filename(struct MPContext *mpctx,
                                                     const char *fname)
 {
@@ -216,21 +227,9 @@ static char *mp_get_playback_resume_config_filename(struct MPContext *mpctx,
     for (int i = 0; i < 16; i++)
         conf = talloc_asprintf_append(conf, "%02X", md5[i]);
 
-    if (!mpctx->cached_watch_later_configdir) {
-        char *wl_dir = mpctx->opts->watch_later_directory;
-        if (wl_dir && wl_dir[0]) {
-            mpctx->cached_watch_later_configdir =
-                mp_get_user_path(mpctx, mpctx->global, wl_dir);
-        }
-    }
-
-    if (!mpctx->cached_watch_later_configdir) {
-        mpctx->cached_watch_later_configdir =
-            mp_find_user_file(mpctx, mpctx->global, "home", MP_WATCH_LATER_CONF);
-    }
-
-    if (mpctx->cached_watch_later_configdir)
-        res = mp_path_join(NULL, mpctx->cached_watch_later_configdir, conf);
+    char *wl_dir = mp_get_playback_resume_dir(mpctx);
+    if (wl_dir && wl_dir[0])
+        res = mp_path_join(NULL, wl_dir, conf);
 
 exit:
     talloc_free(tmp);
@@ -292,7 +291,8 @@ void mp_write_watch_later_conf(struct MPContext *mpctx)
     if (!conffile)
         goto exit;
 
-    mp_mk_user_dir(mpctx->global, "home", mpctx->cached_watch_later_configdir);
+    char *wl_dir = mp_get_playback_resume_dir(mpctx);
+    mp_mk_user_dir(mpctx->global, "state", wl_dir);
 
     MP_INFO(mpctx, "Saving state.\n");
 

player/core.h

@@ -424,8 +424,6 @@ typedef struct MPContext {
 
     struct mp_recorder *recorder;
 
-    char *cached_watch_later_configdir;
-
     struct screenshot_ctx *screenshot_ctx;
     struct command_ctx *command_ctx;
     struct encode_lavc_context *encode_lavc_ctx;