/*
  * AVPacket functions for libavcodec
  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 

 #include "internal.h"

 #include "libavutil/avassert.h"

 #include "bytestream.h"

 #include "avcodec.h"

 
 void av_destruct_packet_nofree(AVPacket *pkt)
 {

     pkt->data            = NULL;
     pkt->size            = 0;

     pkt->side_data       = NULL;
     pkt->side_data_elems = 0;

 }
 

 void ff_packet_free_side_data(AVPacket *pkt)

 {

     int i;
     for (i = 0; i < pkt->side_data_elems; i++)
         av_free(pkt->side_data[i].data);
     av_freep(&pkt->side_data);
     pkt->side_data_elems = 0;

 }
 

 void av_destruct_packet(AVPacket *pkt)
 {
     av_free(pkt->data);

     pkt->data = NULL;
     pkt->size = 0;

 
     ff_packet_free_side_data(pkt);
 }
 

 void av_init_packet(AVPacket *pkt)
 {

     pkt->pts                  = AV_NOPTS_VALUE;
     pkt->dts                  = AV_NOPTS_VALUE;
     pkt->pos                  = -1;
     pkt->duration             = 0;

     pkt->convergence_duration = 0;

     pkt->flags                = 0;
     pkt->stream_index         = 0;
     pkt->destruct             = NULL;
     pkt->side_data            = NULL;
     pkt->side_data_elems      = 0;

 }
 
 int av_new_packet(AVPacket *pkt, int size)
 {

     uint8_t *data = NULL;
     if ((unsigned)size < (unsigned)size + FF_INPUT_BUFFER_PADDING_SIZE)

         data = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);

     if (data) {

         memset(data + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

     } else
         size = 0;

 
     av_init_packet(pkt);

     pkt->data     = data;
     pkt->size     = size;

     pkt->destruct = av_destruct_packet;

     if (!data)

         return AVERROR(ENOMEM);

     return 0;
 }
 

 void av_shrink_packet(AVPacket *pkt, int size)
 {

     if (pkt->size <= size)
         return;

     pkt->size = size;
     memset(pkt->data + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
 }
 

 int av_grow_packet(AVPacket *pkt, int grow_by)
 {
     void *new_ptr;
     av_assert0((unsigned)pkt->size <= INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE);
     if (!pkt->size)
         return av_new_packet(pkt, grow_by);

     if ((unsigned)grow_by >
         INT_MAX - (pkt->size + FF_INPUT_BUFFER_PADDING_SIZE))

         return -1;

     new_ptr = av_realloc(pkt->data,
                          pkt->size + grow_by + FF_INPUT_BUFFER_PADDING_SIZE);

     if (!new_ptr)
         return AVERROR(ENOMEM);

     pkt->data  = new_ptr;

     pkt->size += grow_by;
     memset(pkt->data + pkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
     return 0;
 }
 

 #define DUP_DATA(dst, src, size, padding)                               \
     do {                                                                \
         void *data;                                                     \
         if (padding) {                                                  \
             if ((unsigned)(size) >                                      \
                 (unsigned)(size) + FF_INPUT_BUFFER_PADDING_SIZE)        \
                 goto failed_alloc;                                      \
             data = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);      \
         } else {                                                        \
             data = av_malloc(size);                                     \
         }                                                               \
         if (!data)                                                      \
             goto failed_alloc;                                          \
         memcpy(data, src, size);                                        \
         if (padding)                                                    \
             memset((uint8_t *)data + size, 0,                           \
                    FF_INPUT_BUFFER_PADDING_SIZE);                       \
         dst = data;                                                     \
     } while (0)

 int av_dup_packet(AVPacket *pkt)
 {

     AVPacket tmp_pkt;
 

     if (((pkt->destruct == av_destruct_packet_nofree) ||
          (pkt->destruct == NULL)) && pkt->data) {

         tmp_pkt = *pkt;
 
         pkt->data      = NULL;
         pkt->side_data = NULL;
         DUP_DATA(pkt->data, tmp_pkt.data, pkt->size, 1);

         pkt->destruct = av_destruct_packet;

 
         if (pkt->side_data_elems) {
             int i;
 

             DUP_DATA(pkt->side_data, tmp_pkt.side_data,
                      pkt->side_data_elems * sizeof(*pkt->side_data), 0);

             memset(pkt->side_data, 0,
                    pkt->side_data_elems * sizeof(*pkt->side_data));
             for (i = 0; i < pkt->side_data_elems; i++)

                 DUP_DATA(pkt->side_data[i].data, tmp_pkt.side_data[i].data,
                          pkt->side_data[i].size, 1);

         }

     }
     return 0;

 failed_alloc:
     av_destruct_packet(pkt);
     return AVERROR(ENOMEM);

 }

 
 void av_free_packet(AVPacket *pkt)
 {
     if (pkt) {

         if (pkt->destruct)
             pkt->destruct(pkt);
         pkt->data            = NULL;
         pkt->size            = 0;

         pkt->side_data       = NULL;
         pkt->side_data_elems = 0;
     }
 }
 

 uint8_t *av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,

                                  int size)
 {
     int elems = pkt->side_data_elems;
 
     if ((unsigned)elems + 1 > INT_MAX / sizeof(*pkt->side_data))
         return NULL;
     if ((unsigned)size > INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE)
         return NULL;
 

     pkt->side_data = av_realloc(pkt->side_data,
                                 (elems + 1) * sizeof(*pkt->side_data));

     if (!pkt->side_data)
         return NULL;
 
     pkt->side_data[elems].data = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);
     if (!pkt->side_data[elems].data)
         return NULL;
     pkt->side_data[elems].size = size;
     pkt->side_data[elems].type = type;
     pkt->side_data_elems++;
 
     return pkt->side_data[elems].data;
 }
 

 uint8_t *av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,

                                  int *size)
 {
     int i;
 
     for (i = 0; i < pkt->side_data_elems; i++) {
         if (pkt->side_data[i].type == type) {
             if (size)
                 *size = pkt->side_data[i].size;
             return pkt->side_data[i].data;
         }

     }

     return NULL;

 }

 
 #define FF_MERGE_MARKER 0x8c4d9d108e25e9feULL
 
 int av_packet_merge_side_data(AVPacket *pkt){
     if(pkt->side_data_elems){
         int i;
         uint8_t *p;
         uint64_t size= pkt->size + 8LL + FF_INPUT_BUFFER_PADDING_SIZE;
         AVPacket old= *pkt;
         for (i=0; i<old.side_data_elems; i++) {
             size += old.side_data[i].size + 5LL;
         }
         if (size > INT_MAX)
             return AVERROR(EINVAL);
         p = av_malloc(size);
         if (!p)
             return AVERROR(ENOMEM);
         pkt->data = p;
         pkt->destruct = av_destruct_packet;
         pkt->size = size - FF_INPUT_BUFFER_PADDING_SIZE;
         bytestream_put_buffer(&p, old.data, old.size);
         for (i=old.side_data_elems-1; i>=0; i--) {
             bytestream_put_buffer(&p, old.side_data[i].data, old.side_data[i].size);
             bytestream_put_be32(&p, old.side_data[i].size);
             *p++ = old.side_data[i].type | ((i==old.side_data_elems-1)*128);
         }
         bytestream_put_be64(&p, FF_MERGE_MARKER);
         av_assert0(p-pkt->data == pkt->size);
         memset(p, 0, FF_INPUT_BUFFER_PADDING_SIZE);
         av_free_packet(&old);
         pkt->side_data_elems = 0;
         pkt->side_data = NULL;
         return 1;
     }
     return 0;
 }
 
 int av_packet_split_side_data(AVPacket *pkt){
     if (!pkt->side_data_elems && pkt->size >12 && AV_RB64(pkt->data + pkt->size - 8) == FF_MERGE_MARKER){
         int i;
         unsigned int size;

         uint8_t *p;

         p = pkt->data + pkt->size - 8 - 5;

         for (i=1; ; i++){
             size = AV_RB32(p);

             if (size>INT_MAX || p - pkt->data < size)

                 return 0;
             if (p[4]&128)
                 break;
             p-= size+5;
         }
 
         pkt->side_data = av_malloc(i * sizeof(*pkt->side_data));
         if (!pkt->side_data)
             return AVERROR(ENOMEM);
 
         p= pkt->data + pkt->size - 8 - 5;
         for (i=0; ; i++){
             size= AV_RB32(p);

             av_assert0(size<=INT_MAX && p - pkt->data >= size);

             pkt->side_data[i].data = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);
             pkt->side_data[i].size = size;
             pkt->side_data[i].type = p[4]&127;
             if (!pkt->side_data[i].data)
                 return AVERROR(ENOMEM);
             memcpy(pkt->side_data[i].data, p-size, size);
             pkt->size -= size + 5;
             if(p[4]&128)
                 break;
             p-= size+5;
         }
         pkt->size -= 8;
         pkt->side_data_elems = i+1;
         return 1;
     }
     return 0;
 }

 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
                                int size)
 {
     int i;
 
     for (i = 0; i < pkt->side_data_elems; i++) {
         if (pkt->side_data[i].type == type) {
             if (size > pkt->side_data[i].size)
                 return AVERROR(ENOMEM);
             pkt->side_data[i].size = size;
             return 0;
         }
     }
     return AVERROR(ENOENT);
 }