hls: read protocol options through the AVIOContext

This reverts commit 9f9ed79d.

The hlsopts member was never set anywhere and always NULL, furthermore
the HLS demuxer needs to retrieve the proper options from the underlying
http protocol (cookies, user-agent, etc), so a dummy context won't help.

Instead, use the AVIOContext directly to access the options.

libavformat/avio_internal.h

@@ -24,11 +24,6 @@
 
 #include "libavutil/log.h"
 
-typedef struct AVIOInternal {
-    URLContext *h;
-    void *hlsopts;
-} AVIOInternal;
-
 extern const AVClass ff_avio_class;
 
 int ffio_init_context(AVIOContext *s,

libavformat/aviobuf.c

@@ -42,6 +42,10 @@
  */
 #define SHORT_SEEK_THRESHOLD 4096
 
+typedef struct AVIOInternal {
+    URLContext *h;
+} AVIOInternal;
+
 static void *ff_avio_child_next(void *obj, void *prev)
 {
     AVIOContext *s = obj;

libavformat/hls.c

@@ -584,7 +584,7 @@ static int ensure_playlist(HLSContext *c, struct playlist **pls, const char *url
 static void update_options(char **dest, const char *name, void *src)
 {
     av_freep(dest);
-    av_opt_get(src, name, 0, (uint8_t**)dest);
+    av_opt_get(src, name, AV_OPT_SEARCH_CHILDREN, (uint8_t**)dest);
     if (*dest && !strlen(*dest))
         av_freep(dest);
 }
@@ -614,8 +614,7 @@ static int open_url(AVFormatContext *s, AVIOContext **pb, const char *url,
     ret = s->io_open(s, pb, url, AVIO_FLAG_READ, &tmp);
     if (ret >= 0) {
         // update cookies on http response with setcookies.
-        AVIOInternal *internal = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb->opaque;
-        void *u = internal ? internal->hlsopts : NULL;
+        void *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb;
         update_options(&c->cookies, "cookies", u);
         av_dict_set(&opts, "cookies", c->cookies, 0);
     }
@@ -1497,8 +1496,7 @@ static int nested_io_open(AVFormatContext *s, AVIOContext **pb, const char *url,
 
 static int hls_read_header(AVFormatContext *s)
 {
-    AVIOInternal *internal = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb->opaque;
-    void *u = internal ? internal->hlsopts : NULL;
+    void *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb;
     HLSContext *c = s->priv_data;
     int ret = 0, i, j, stream_offset = 0;