stream_dvd: better .ifo probing

stream_dvd.c includes a pseudo-protocol that recognizes .IFO files, and
plays them using libdvdread. This was relatively lazy, and could perhaps
easily trigger with files that just had the .ifo extension.

Make the checks stricter, and even probe the file header. Apparently the
first bytes in an .ifo file are always "DVDVIDEO-VTS", so check for
this.

Refuse to load the main "video_ts.ifo". The plan is to use stream_dvdnav
for it.

This also removes at least 1 memory leak.

1 files changed, 11 insertions, 0 deletions

diff --git a/stream/stream_file.c b/stream/stream_file.c
index 6a10114832..eef0dcc5cc 100644
--- a/stream/stream_file.c
+++ b/stream/stream_file.c
@@ -126,6 +126,17 @@ char *mp_file_url_to_filename(void *talloc_ctx, bstr url)
     return filename;
 }
 
+// Return talloc_strdup's filesystem path if local, otherwise NULL.
+// Unlike mp_file_url_to_filename(), doesn't return NULL if already local.
+char *mp_file_get_path(void *talloc_ctx, bstr url)
+{
+    if (mp_split_proto(url, &(bstr){0}).len) {
+        return mp_file_url_to_filename(talloc_ctx, url);
+    } else {
+        return bstrto0(talloc_ctx, url);
+    }
+}
+
 #if HAVE_BSD_FSTATFS
 static bool check_stream_network(stream_t *stream)
 {