win32: add portable config mode

See manpage additions.

The main reason for adding this is that we can't guess whether the user
wants his config in his Windows profile or not. The user basically has
to tell mpv what should be done, and the "portable_config" directory
does this implicitly.

Fixes #2042 (approximately).

2 files changed, 38 insertions, 9 deletions

diff --git a/DOCS/man/mpv.rst b/DOCS/man/mpv.rst
index 55da5d9b0a..84d72b070e 100644
--- a/DOCS/man/mpv.rst
+++ b/DOCS/man/mpv.rst
@@ -881,6 +881,14 @@ Other config files (such as ``input.conf``) are in the same directory. See the
 The environment variable ``$MPV_HOME`` completely overrides these, like on
 UNIX.
 
+If a directory named ``portable_config`` next to the mpv.exe exists, all
+config will be loaded from this directory only. Watch later config files are
+written to this directory as well. (This exists on Windows only and is redundant
+with ``$MPV_HOME``. However, since Windows is very scripting unfriendly, a
+wrapper script just setting ``$MPV_HOME``, like you could do it on other
+systems, won't work. ``portable_config`` is provided for convenience to get
+around this restriction.)
+
 Config files located in the same directory as ``mpv.exe`` are loaded with
 lower priority. Some config files are loaded only once, which means that
 e.g. of 2 ``input.conf`` files located in two config directories, only the
diff --git a/osdep/path-win.c b/osdep/path-win.c
index d0c29556d1..a735fad069 100644
--- a/osdep/path-win.c
+++ b/osdep/path-win.c
@@ -17,6 +17,7 @@
 
 #include <windows.h>
 #include <shlobj.h>
+#include <pthread.h>
 
 #include "osdep/path.h"
 #include "osdep/io.h"
@@ -24,6 +25,10 @@
 
 // Warning: do not use PATH_MAX. Cygwin messed it up.
 
+static pthread_once_t path_init_once = PTHREAD_ONCE_INIT;
+
+static char *portable_path;
+
 static char *mp_get_win_exe_dir(void *talloc_ctx)
 {
     wchar_t w_exedir[MAX_PATH + 1] = {0};
@@ -42,9 +47,9 @@ static char *mp_get_win_exe_dir(void *talloc_ctx)
     return mp_to_utf8(talloc_ctx, w_exedir);
 }
 
-static char *mp_get_win_exe_subdir(void *talloc_ctx)
+static char *mp_get_win_exe_subdir(void *ta_ctx, const char *name)
 {
-    return talloc_asprintf(talloc_ctx, "%s/mpv", mp_get_win_exe_dir(talloc_ctx));
+    return talloc_asprintf(ta_ctx, "%s/%s", mp_get_win_exe_dir(ta_ctx), name);
 }
 
 static char *mp_get_win_shell_dir(void *talloc_ctx, int folder)
@@ -64,15 +69,31 @@ static char *mp_get_win_app_dir(void *talloc_ctx)
     return path ? mp_path_join(talloc_ctx, path, "mpv") : NULL;
 }
 
+
+static void path_init(void)
+{
+    void *tmp = talloc_new(NULL);
+    char *path = mp_get_win_exe_subdir(tmp, "portable_config");
+    if (path && mp_path_exists(path))
+        portable_path = talloc_strdup(NULL, path);
+    talloc_free(tmp);
+}
+
 const char *mp_get_platform_path_win(void *talloc_ctx, const char *type)
 {
-    if (strcmp(type, "home") == 0)
-        return mp_get_win_app_dir(talloc_ctx);
-    if (strcmp(type, "old_home") == 0)
-        return mp_get_win_exe_dir(talloc_ctx);
-    // Not really true, but serves as a way to return a lowest-priority dir.
-    if (strcmp(type, "global") == 0)
-        return mp_get_win_exe_subdir(talloc_ctx);
+    pthread_once(&path_init_once, path_init);
+    if (portable_path) {
+        if (strcmp(type, "home") == 0)
+            return portable_path;
+    } else {
+        if (strcmp(type, "home") == 0)
+            return mp_get_win_app_dir(talloc_ctx);
+        if (strcmp(type, "old_home") == 0)
+            return mp_get_win_exe_dir(talloc_ctx);
+        // Not really true, but serves as a way to return a lowest-priority dir.
+        if (strcmp(type, "global") == 0)
+            return mp_get_win_exe_subdir(talloc_ctx, "mpv");
+    }
     if (strcmp(type, "desktop") == 0)
         return mp_get_win_shell_dir(talloc_ctx, CSIDL_DESKTOPDIRECTORY);
     return NULL;