command: add playlist-next-playlist and playlist-prev-playlist

[guidocella]

playlist-prev-playlist goes to the beginning of the previous playlist because this seems more useful and symmetrical to playlist-next-playlist. It does not go to the beginning when the current playlist-path starts with the previous playlist-path, e.g. with mpv --loop-playlist foo/, which expands to foo/{1..9}.zip, the current playlist path foo/1.zip beings with the playlist-path foo/ of {2..9}.zip and thus playlist-prev-playlist goes to 9.zip rather than to 2.zip.

Closes #12495.

[github-actions]

Download the artifacts for this pull request:

Windows

• mpv-i686-w64-mingw32
• mpv-x86_64-w64-mingw32

[guidocella]

Rebased.

[debugzxcv]

mpv crashed after call playlist-prev-playlist

Reproduction steps

1. mpv https://www.youtube.com/playlist?list=OLAK5uy_mwn8JPCdjhaRVc3PQa3OCm8SAj9z1EB2I
2. open console enter:
   1. loadfile https://www.youtube.com/playlist?list=OLAK5uy_lJyd9QdMb84CCdEoT4ZnqfZ37Byz-M_kE append
   2. playlist-next-playlist
   3. playlist-prev-playlist

[guidocella]

This was fixed months ago.

[debugzxcv]

Still able to reproduce the issue using https://github.com/zhongfly/mpv-winbuild/releases/tag/2024-02-18-3fd840f with --no-config --script-opts-add=ytdl_hook-try_ytdl_first=yes

[guidocella]

I can't reproduce that.

[debugzxcv]

Looks like it's crashing here:

mpv/common/playlist.c

Lines 262 to 269 in 4a563a6

	if (bstr_startswith(bstr0(current_playlist_path),
	bstr0(talloc_strdup_append(playlist_path, "/")))
	#if HAVE_DOS_PATHS
	||
	bstr_startswith(bstr0(current_playlist_path),
	bstr0(talloc_strdup_append(playlist_path, "\\")))
	#endif
	)

I don't know how to fix it properly, but this patch works:

diff --git a/common/playlist.c b/common/playlist.c
index 5de8e627..e223a292 100644
--- a/common/playlist.c
+++ b/common/playlist.c
@@ -259,14 +259,14 @@ struct playlist_entry *playlist_get_first_in_same_playlist(
     // work in all cases.
     char* playlist_path = talloc_strdup(tmp, entry->playlist_path);
     mp_path_strip_trailing_separator(playlist_path);
-    if (bstr_startswith(bstr0(current_playlist_path),
+    if (!mp_is_url(bstr0(current_playlist_path)) && (bstr_startswith(bstr0(current_playlist_path),
                         bstr0(talloc_strdup_append(playlist_path, "/")))
 #if HAVE_DOS_PATHS
         ||
         bstr_startswith(bstr0(current_playlist_path),
                         bstr0(talloc_strdup_append(playlist_path, "\\")))
 #endif
-       )
+       ))
         goto exit;
 
     struct playlist_entry *prev = playlist_entry_get_rel(entry, -1);

[guidocella]

It still doesn't crash for me and I don't understand why you should skip that check with URLs.

[Dudemanguy]

I also cannot reproduce. Dunno, check if there's something weird in your config causing this although I don't know what that would be.