lavf: deobfuscate read_frame_internal().

Split off packet parsing into a separate function. Parse full packets at
once and store them in a queue, eliminating the need for tracking
parsing state in AVStream.

The horrible unreadable loop in read_frame_internal() now isn't weirdly
ordered and doesn't contain evil gotos, so it should be much easier to
understand.

compute_pkt_fields() now invents slightly different timestamps for two
raw vc1 tests, due to has_b_frames being set a bit later. They shouldn't
be more wrong (or right) than previous ones.

1 files changed, 5 insertions, 7 deletions

diff --git a/libavformat/avformat.h b/libavformat/avformat.h
index 65ed376c89..9b40eee395 100644
--- a/libavformat/avformat.h
+++ b/libavformat/avformat.h
@@ -639,10 +639,6 @@ typedef struct AVStream {
         int nb_decoded_frames;
     } *info;
 
-    AVPacket cur_pkt;
-    const uint8_t *cur_ptr;
-    int cur_len;
-
     int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
 
     // Timestamp generation support:
@@ -922,9 +918,6 @@ typedef struct AVFormatContext {
     struct AVPacketList *packet_buffer;
     struct AVPacketList *packet_buffer_end;
 
-    /* av_read_frame() support */
-    AVStream *cur_st;
-
     /* av_seek_frame() support */
     int64_t data_offset; /**< offset of the first packet */
 
@@ -937,6 +930,11 @@ typedef struct AVFormatContext {
     struct AVPacketList *raw_packet_buffer;
     struct AVPacketList *raw_packet_buffer_end;
     /**
+     * Packets split by the parser get queued here.
+     */
+    struct AVPacketList *parse_queue;
+    struct AVPacketList *parse_queue_end;
+    /**
      * Remaining size available for raw_packet_buffer, in bytes.
      */
 #define RAW_PACKET_BUFFER_SIZE 2500000