player: change --display-tags behavior

Remove the "all" special-behavior, and instead interpret trailing "*"
characters. --display-tags=all is replaced by --display-tags=* as a
special-case of the new behavior.

See #1404.

Note that the most straight-forward value for matchlen in the normal
case would be INT_MAX, because it should be using the entire string.
I used keylen+1 instead, because glibc seems to handle this case
incorrectly:

    snprintf(buf, sizeof(buf), "%.*s", INT_MAX, "hello");

The result is empty, instead of just containing the string argument.
This might be a glibc bug; it works with other libcs (even MinGW-w64).

1 files changed, 2 insertions, 1 deletions

diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst
index 8fdd0c83e3..106a233bd1 100644
--- a/DOCS/man/options.rst
+++ b/DOCS/man/options.rst
@@ -3217,7 +3217,8 @@ Miscellaneous
 ``--display-tags=tag1,tags2,...``
     Set the list of tags that should be displayed on the terminal. Tags that
     are in the list, but are not present in the played file, will not be shown.
-    The special value ``all`` disables filtering.
+    If a value ends with ``*``, all tags are matched by prefix (though there
+    is no general globbing). Just passing ``*`` essentially filtering.
 
     The default includes a common list of tags, call mpv with ``--list-options``
     to see it.