avcodec/packet_internal: Add proper PacketList struct

Up until now, we had a PacketList structure which is actually
a PacketListEntry; a proper PacketList did not exist
and all the related functions just passed pointers to pointers
to the head and tail elements around. All these pointers were
actually consecutive elements of their containing structs,
i.e. the users already treated them as if they were a struct.

So add a proper PacketList struct and rename the current PacketList
to PacketListEntry; also make the functions use this structure
instead of the pair of pointers.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

1 files changed, 16 insertions, 20 deletions

diff --git a/libavcodec/avpacket.c b/libavcodec/avpacket.c
index a0134e405c..4f7a6b255c 100644
--- a/libavcodec/avpacket.c
+++ b/libavcodec/avpacket.c
@@ -535,13 +535,12 @@ void av_packet_rescale_ts(AVPacket *pkt, AVRational src_tb, AVRational dst_tb)
         pkt->duration = av_rescale_q(pkt->duration, src_tb, dst_tb);
 }
 
-int avpriv_packet_list_put(PacketList **packet_buffer,
-                           PacketList **plast_pktl,
+int avpriv_packet_list_put(PacketList *packet_buffer,
                            AVPacket      *pkt,
                            int (*copy)(AVPacket *dst, const AVPacket *src),
                            int flags)
 {
-    PacketList *pktl = av_malloc(sizeof(PacketList));
+    PacketListEntry *pktl = av_malloc(sizeof(*pktl));
     int ret;
 
     if (!pktl)
@@ -565,44 +564,41 @@ int avpriv_packet_list_put(PacketList **packet_buffer,
 
     pktl->next = NULL;
 
-    if (*packet_buffer)
-        (*plast_pktl)->next = pktl;
+    if (packet_buffer->head)
+        packet_buffer->tail->next = pktl;
     else
-        *packet_buffer = pktl;
+        packet_buffer->head = pktl;
 
     /* Add the packet in the buffered packet list. */
-    *plast_pktl = pktl;
+    packet_buffer->tail = pktl;
     return 0;
 }
 
-int avpriv_packet_list_get(PacketList **pkt_buffer,
-                           PacketList **pkt_buffer_end,
+int avpriv_packet_list_get(PacketList *pkt_buffer,
                            AVPacket      *pkt)
 {
-    PacketList *pktl;
-    if (!*pkt_buffer)
+    PacketListEntry *pktl = pkt_buffer->head;
+    if (!pktl)
         return AVERROR(EAGAIN);
-    pktl        = *pkt_buffer;
     *pkt        = pktl->pkt;
-    *pkt_buffer = pktl->next;
-    if (!pktl->next)
-        *pkt_buffer_end = NULL;
+    pkt_buffer->head = pktl->next;
+    if (!pkt_buffer->head)
+        pkt_buffer->tail = NULL;
     av_freep(&pktl);
     return 0;
 }
 
-void avpriv_packet_list_free(PacketList **pkt_buf, PacketList **pkt_buf_end)
+void avpriv_packet_list_free(PacketList *pkt_buf)
 {
-    PacketList *tmp = *pkt_buf;
+    PacketListEntry *tmp = pkt_buf->head;
 
     while (tmp) {
-        PacketList *pktl = tmp;
+        PacketListEntry *pktl = tmp;
         tmp = pktl->next;
         av_packet_unref(&pktl->pkt);
         av_freep(&pktl);
     }
-    *pkt_buf     = NULL;
-    *pkt_buf_end = NULL;
+    pkt_buf->head = pkt_buf->tail = NULL;
 }
 
 int ff_side_data_set_encoder_stats(AVPacket *pkt, int quality, int64_t *error, int error_count, int pict_type)