/*
  * RTMP input format

  * Copyright (c) 2009 Konstantin Shishkov

  *
  * 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 "libavcodec/bytestream.h"
 #include "libavutil/avstring.h"

 #include "libavutil/intfloat.h"

 #include "avformat.h"
 
 #include "rtmppkt.h"
 #include "flv.h"

 #include "url.h"

 
 void ff_amf_write_bool(uint8_t **dst, int val)
 {
     bytestream_put_byte(dst, AMF_DATA_TYPE_BOOL);
     bytestream_put_byte(dst, val);
 }
 
 void ff_amf_write_number(uint8_t **dst, double val)
 {
     bytestream_put_byte(dst, AMF_DATA_TYPE_NUMBER);

     bytestream_put_be64(dst, av_double2int(val));

 }
 
 void ff_amf_write_string(uint8_t **dst, const char *str)
 {
     bytestream_put_byte(dst, AMF_DATA_TYPE_STRING);
     bytestream_put_be16(dst, strlen(str));
     bytestream_put_buffer(dst, str, strlen(str));
 }
 

 void ff_amf_write_string2(uint8_t **dst, const char *str1, const char *str2)
 {
     int len1 = 0, len2 = 0;
     if (str1)
         len1 = strlen(str1);
     if (str2)
         len2 = strlen(str2);
     bytestream_put_byte(dst, AMF_DATA_TYPE_STRING);
     bytestream_put_be16(dst, len1 + len2);
     bytestream_put_buffer(dst, str1, len1);
     bytestream_put_buffer(dst, str2, len2);
 }
 

 void ff_amf_write_null(uint8_t **dst)
 {
     bytestream_put_byte(dst, AMF_DATA_TYPE_NULL);
 }
 
 void ff_amf_write_object_start(uint8_t **dst)
 {
     bytestream_put_byte(dst, AMF_DATA_TYPE_OBJECT);
 }
 
 void ff_amf_write_field_name(uint8_t **dst, const char *str)
 {
     bytestream_put_be16(dst, strlen(str));
     bytestream_put_buffer(dst, str, strlen(str));
 }
 
 void ff_amf_write_object_end(uint8_t **dst)
 {
     /* first two bytes are field name length = 0,
      * AMF object should end with it and end marker
      */
     bytestream_put_be24(dst, AMF_DATA_TYPE_OBJECT_END);
 }
 

 int ff_amf_read_bool(GetByteContext *bc, int *val)
 {
     if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_BOOL)
         return AVERROR_INVALIDDATA;
     *val = bytestream2_get_byte(bc);
     return 0;
 }
 
 int ff_amf_read_number(GetByteContext *bc, double *val)
 {
     uint64_t read;
     if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_NUMBER)
         return AVERROR_INVALIDDATA;
     read = bytestream2_get_be64(bc);
     *val = av_int2double(read);
     return 0;
 }
 

 int ff_amf_get_string(GetByteContext *bc, uint8_t *str,
                       int strsize, int *length)

 {
     int stringlen = 0;
     int readsize;
     stringlen = bytestream2_get_be16(bc);
     if (stringlen + 1 > strsize)
         return AVERROR(EINVAL);
     readsize = bytestream2_get_buffer(bc, str, stringlen);
     if (readsize != stringlen) {
         av_log(NULL, AV_LOG_WARNING,
                "Unable to read as many bytes as AMF string signaled\n");
     }
     str[readsize] = '\0';
     *length = FFMIN(stringlen, readsize);
     return 0;
 }
 

 int ff_amf_read_string(GetByteContext *bc, uint8_t *str,
                        int strsize, int *length)
 {
     if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_STRING)
         return AVERROR_INVALIDDATA;
     return ff_amf_get_string(bc, str, strsize, length);
 }
 

 int ff_amf_read_null(GetByteContext *bc)
 {
     if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_NULL)
         return AVERROR_INVALIDDATA;
     return 0;
 }
 

 int ff_rtmp_check_alloc_array(RTMPPacket **prev_pkt, int *nb_prev_pkt,
                               int channel)
 {
     int nb_alloc;
     RTMPPacket *ptr;
     if (channel < *nb_prev_pkt)
         return 0;
 
     nb_alloc = channel + 16;
     // This can't use the av_reallocp family of functions, since we
     // would need to free each element in the array before the array
     // itself is freed.
     ptr = av_realloc_array(*prev_pkt, nb_alloc, sizeof(**prev_pkt));
     if (!ptr)
         return AVERROR(ENOMEM);
     memset(ptr + *nb_prev_pkt, 0, (nb_alloc - *nb_prev_pkt) * sizeof(*ptr));
     *prev_pkt = ptr;
     *nb_prev_pkt = nb_alloc;
     return 0;
 }
 

 int ff_rtmp_packet_read(URLContext *h, RTMPPacket *p,

                         int chunk_size, RTMPPacket **prev_pkt, int *nb_prev_pkt)

 {

     uint8_t hdr;
 
     if (ffurl_read(h, &hdr, 1) != 1)
         return AVERROR(EIO);
 

     return ff_rtmp_packet_read_internal(h, p, chunk_size, prev_pkt,
                                         nb_prev_pkt, hdr);

 }
 

 static int rtmp_packet_read_one_chunk(URLContext *h, RTMPPacket *p,

                                       int chunk_size, RTMPPacket **prev_pkt_ptr,
                                       int *nb_prev_pkt, uint8_t hdr)

 {
 

     uint8_t buf[16];
     int channel_id, timestamp, size;

     uint32_t ts_field; // non-extended timestamp or delta field

     uint32_t extra = 0;

     enum RTMPPacketType type;

     int written = 0;

     int ret, toread;

     RTMPPacket *prev_pkt;

     written++;

     channel_id = hdr & 0x3F;
 

     if (channel_id < 2) { //special case for channel number >= 64
         buf[1] = 0;

         if (ffurl_read_complete(h, buf, channel_id + 1) != channel_id + 1)

             return AVERROR(EIO);

         written += channel_id + 1;

         channel_id = AV_RL16(buf) + 64;
     }

     if ((ret = ff_rtmp_check_alloc_array(prev_pkt_ptr, nb_prev_pkt,
                                          channel_id)) < 0)
         return ret;
     prev_pkt = *prev_pkt_ptr;

     size  = prev_pkt[channel_id].size;
     type  = prev_pkt[channel_id].type;
     extra = prev_pkt[channel_id].extra;

     hdr >>= 6; // header size indicator

     if (hdr == RTMP_PS_ONEBYTE) {

         ts_field = prev_pkt[channel_id].ts_field;

     } else {

         if (ffurl_read_complete(h, buf, 3) != 3)

             return AVERROR(EIO);

         written += 3;

         ts_field = AV_RB24(buf);

         if (hdr != RTMP_PS_FOURBYTES) {

             if (ffurl_read_complete(h, buf, 3) != 3)

                 return AVERROR(EIO);

             written += 3;
             size = AV_RB24(buf);

             if (ffurl_read_complete(h, buf, 1) != 1)

                 return AVERROR(EIO);

             written++;

             type = buf[0];

             if (hdr == RTMP_PS_TWELVEBYTES) {

                 if (ffurl_read_complete(h, buf, 4) != 4)

                     return AVERROR(EIO);

                 written += 4;

                 extra = AV_RL32(buf);
             }
         }

     }
     if (ts_field == 0xFFFFFF) {
         if (ffurl_read_complete(h, buf, 4) != 4)
             return AVERROR(EIO);
         timestamp = AV_RB32(buf);
     } else {
         timestamp = ts_field;

     }

     if (hdr != RTMP_PS_TWELVEBYTES)
         timestamp += prev_pkt[channel_id].timestamp;
 

     if (prev_pkt[channel_id].read && size != prev_pkt[channel_id].size) {

         av_log(h, AV_LOG_ERROR, "RTMP packet size mismatch %d != %d\n",
                                 size, prev_pkt[channel_id].size);

         ff_rtmp_packet_destroy(&prev_pkt[channel_id]);
         prev_pkt[channel_id].read = 0;

         return AVERROR_INVALIDDATA;

     }
 

     if (!prev_pkt[channel_id].read) {
         if ((ret = ff_rtmp_packet_create(p, channel_id, type, timestamp,
                                          size)) < 0)
             return ret;
         p->read = written;
         p->offset = 0;

         prev_pkt[channel_id].ts_field   = ts_field;

         prev_pkt[channel_id].timestamp  = timestamp;
     } else {
         // previous packet in this channel hasn't completed reading
         RTMPPacket *prev = &prev_pkt[channel_id];
         p->data          = prev->data;
         p->size          = prev->size;
         p->channel_id    = prev->channel_id;
         p->type          = prev->type;

         p->ts_field      = prev->ts_field;

         p->extra         = prev->extra;
         p->offset        = prev->offset;
         p->read          = prev->read + written;
         p->timestamp     = prev->timestamp;
         prev->data       = NULL;
     }

     p->extra = extra;
     // save history
     prev_pkt[channel_id].channel_id = channel_id;
     prev_pkt[channel_id].type       = type;

     prev_pkt[channel_id].size       = size;

     prev_pkt[channel_id].extra      = extra;

     size = size - p->offset;
 
     toread = FFMIN(size, chunk_size);
     if (ffurl_read_complete(h, p->data + p->offset, toread) != toread) {
         ff_rtmp_packet_destroy(p);
         return AVERROR(EIO);
     }
     size      -= toread;
     p->read   += toread;
     p->offset += toread;
 
     if (size > 0) {
        RTMPPacket *prev = &prev_pkt[channel_id];
        prev->data = p->data;
        prev->read = p->read;
        prev->offset = p->offset;

        p->data      = NULL;

        return AVERROR(EAGAIN);
     }
 
     prev_pkt[channel_id].read = 0; // read complete; reset if needed
     return p->read;
 }
 
 int ff_rtmp_packet_read_internal(URLContext *h, RTMPPacket *p, int chunk_size,

                                  RTMPPacket **prev_pkt, int *nb_prev_pkt,
                                  uint8_t hdr)

 {
     while (1) {

         int ret = rtmp_packet_read_one_chunk(h, p, chunk_size, prev_pkt,
                                              nb_prev_pkt, hdr);

         if (ret > 0 || ret != AVERROR(EAGAIN))
             return ret;
 
         if (ffurl_read(h, &hdr, 1) != 1)

             return AVERROR(EIO);
     }
 }
 
 int ff_rtmp_packet_write(URLContext *h, RTMPPacket *pkt,

                          int chunk_size, RTMPPacket **prev_pkt_ptr,
                          int *nb_prev_pkt)

 {
     uint8_t pkt_hdr[16], *p = pkt_hdr;
     int mode = RTMP_PS_TWELVEBYTES;
     int off = 0;

     int written = 0;

     int ret;

     RTMPPacket *prev_pkt;

     int use_delta; // flag if using timestamp delta, not RTMP_PS_TWELVEBYTES
     uint32_t timestamp; // full 32-bit timestamp or delta value

 
     if ((ret = ff_rtmp_check_alloc_array(prev_pkt_ptr, nb_prev_pkt,
                                          pkt->channel_id)) < 0)
         return ret;
     prev_pkt = *prev_pkt_ptr;

     //if channel_id = 0, this is first presentation of prev_pkt, send full hdr.

     use_delta = prev_pkt[pkt->channel_id].channel_id &&

         pkt->extra == prev_pkt[pkt->channel_id].extra &&

         pkt->timestamp >= prev_pkt[pkt->channel_id].timestamp;
 
     timestamp = pkt->timestamp;
     if (use_delta) {
         timestamp -= prev_pkt[pkt->channel_id].timestamp;
     }
     if (timestamp >= 0xFFFFFF) {

         pkt->ts_field = 0xFFFFFF;

     } else {

         pkt->ts_field = timestamp;

     }
 
     if (use_delta) {

         if (pkt->type == prev_pkt[pkt->channel_id].type &&

             pkt->size == prev_pkt[pkt->channel_id].size) {

             mode = RTMP_PS_FOURBYTES;

             if (pkt->ts_field == prev_pkt[pkt->channel_id].ts_field)

                 mode = RTMP_PS_ONEBYTE;
         } else {
             mode = RTMP_PS_EIGHTBYTES;
         }
     }
 

     if (pkt->channel_id < 64) {
         bytestream_put_byte(&p, pkt->channel_id | (mode << 6));
     } else if (pkt->channel_id < 64 + 256) {
         bytestream_put_byte(&p, 0               | (mode << 6));
         bytestream_put_byte(&p, pkt->channel_id - 64);
     } else {
         bytestream_put_byte(&p, 1               | (mode << 6));
         bytestream_put_le16(&p, pkt->channel_id - 64);
     }

     if (mode != RTMP_PS_ONEBYTE) {

         bytestream_put_be24(&p, pkt->ts_field);

         if (mode != RTMP_PS_FOURBYTES) {

             bytestream_put_be24(&p, pkt->size);

             bytestream_put_byte(&p, pkt->type);
             if (mode == RTMP_PS_TWELVEBYTES)
                 bytestream_put_le32(&p, pkt->extra);
         }
     }

     if (pkt->ts_field == 0xFFFFFF)

         bytestream_put_be32(&p, timestamp);

     // save history
     prev_pkt[pkt->channel_id].channel_id = pkt->channel_id;
     prev_pkt[pkt->channel_id].type       = pkt->type;

     prev_pkt[pkt->channel_id].size       = pkt->size;

     prev_pkt[pkt->channel_id].timestamp  = pkt->timestamp;

     prev_pkt[pkt->channel_id].ts_field   = pkt->ts_field;

     prev_pkt[pkt->channel_id].extra      = pkt->extra;
 

     if ((ret = ffurl_write(h, pkt_hdr, p - pkt_hdr)) < 0)
         return ret;

     written = p - pkt_hdr + pkt->size;
     while (off < pkt->size) {
         int towrite = FFMIN(chunk_size, pkt->size - off);

         if ((ret = ffurl_write(h, pkt->data + off, towrite)) < 0)
             return ret;

         off += towrite;

         if (off < pkt->size) {

             uint8_t marker = 0xC0 | pkt->channel_id;

             if ((ret = ffurl_write(h, &marker, 1)) < 0)
                 return ret;

             written++;

             if (pkt->ts_field == 0xFFFFFF) {
                 uint8_t ts_header[4];
                 AV_WB32(ts_header, timestamp);
                 if ((ret = ffurl_write(h, ts_header, 4)) < 0)
                     return ret;
                 written += 4;
             }

         }
     }

     return written;

 }
 
 int ff_rtmp_packet_create(RTMPPacket *pkt, int channel_id, RTMPPacketType type,
                           int timestamp, int size)
 {

     if (size) {

         pkt->data = av_realloc(NULL, size);

         if (!pkt->data)
             return AVERROR(ENOMEM);

     }

     pkt->size       = size;

     pkt->channel_id = channel_id;
     pkt->type       = type;
     pkt->timestamp  = timestamp;
     pkt->extra      = 0;

     pkt->ts_field   = 0;

 
     return 0;
 }
 
 void ff_rtmp_packet_destroy(RTMPPacket *pkt)
 {
     if (!pkt)
         return;
     av_freep(&pkt->data);

     pkt->size = 0;

 }
 

 static int amf_tag_skip(GetByteContext *gb)

 {

     AMFDataType type;
     unsigned nb   = -1;
     int parse_key = 1;

     if (bytestream2_get_bytes_left(gb) < 1)

         return -1;

 
     type = bytestream2_get_byte(gb);
     switch (type) {
     case AMF_DATA_TYPE_NUMBER:
         bytestream2_get_be64(gb);
         return 0;
     case AMF_DATA_TYPE_BOOL:
         bytestream2_get_byte(gb);
         return 0;
     case AMF_DATA_TYPE_STRING:
         bytestream2_skip(gb, bytestream2_get_be16(gb));
         return 0;
     case AMF_DATA_TYPE_LONG_STRING:
         bytestream2_skip(gb, bytestream2_get_be32(gb));
         return 0;
     case AMF_DATA_TYPE_NULL:
         return 0;
     case AMF_DATA_TYPE_DATE:
         bytestream2_skip(gb, 10);
         return 0;

     case AMF_DATA_TYPE_ARRAY:

         parse_key = 0;
     case AMF_DATA_TYPE_MIXEDARRAY:

         nb = bytestream2_get_be32(gb);

     case AMF_DATA_TYPE_OBJECT:

         while (nb-- > 0 || type != AMF_DATA_TYPE_ARRAY) {

             int t;

             if (parse_key) {

                 int size = bytestream2_get_be16(gb);

                 if (!size) {

                     bytestream2_get_byte(gb);

                     break;
                 }

                 if (size < 0 || size >= bytestream2_get_bytes_left(gb))

                     return -1;

                 bytestream2_skip(gb, size);

             }

             t = amf_tag_skip(gb);
             if (t < 0 || bytestream2_get_bytes_left(gb) <= 0)

                 return -1;
         }

         return 0;
     case AMF_DATA_TYPE_OBJECT_END:  return 0;

     default:                        return -1;
     }
 }
 

 int ff_amf_tag_size(const uint8_t *data, const uint8_t *data_end)
 {
     GetByteContext gb;
     int ret;
 
     if (data >= data_end)
         return -1;
 
     bytestream2_init(&gb, data, data_end - data);
 
     ret = amf_tag_skip(&gb);
     if (ret < 0 || bytestream2_get_bytes_left(&gb) <= 0)
         return -1;
     av_assert0(bytestream2_tell(&gb) >= 0 && bytestream2_tell(&gb) <= data_end - data);
     return bytestream2_tell(&gb);
 }
 

 static int amf_get_field_value2(GetByteContext *gb,

                            const uint8_t *name, uint8_t *dst, int dst_size)
 {
     int namelen = strlen(name);
     int len;
 

     while (bytestream2_peek_byte(gb) != AMF_DATA_TYPE_OBJECT && bytestream2_get_bytes_left(gb) > 0) {
         int ret = amf_tag_skip(gb);
         if (ret < 0)
             return -1;

     }

     if (bytestream2_get_bytes_left(gb) < 3)

         return -1;

     bytestream2_get_byte(gb);
 

     for (;;) {

         int size = bytestream2_get_be16(gb);

         if (!size)
             break;

         if (size < 0 || size >= bytestream2_get_bytes_left(gb))

             return -1;

         bytestream2_skip(gb, size);
         if (size == namelen && !memcmp(gb->buffer-size, name, namelen)) {
             switch (bytestream2_get_byte(gb)) {

             case AMF_DATA_TYPE_NUMBER:

                 snprintf(dst, dst_size, "%g", av_int2double(bytestream2_get_be64(gb)));

                 break;
             case AMF_DATA_TYPE_BOOL:

                 snprintf(dst, dst_size, "%s", bytestream2_get_byte(gb) ? "true" : "false");

                 break;
             case AMF_DATA_TYPE_STRING:

                 len = bytestream2_get_be16(gb);
                 if (dst_size < 1)
                     return -1;
                 if (dst_size < len + 1)
                     len = dst_size - 1;
                 bytestream2_get_buffer(gb, dst, len);
                 dst[len] = 0;

                 break;
             default:
                 return -1;
             }
             return 0;
         }

         len = amf_tag_skip(gb);
         if (len < 0 || bytestream2_get_bytes_left(gb) <= 0)

             return -1;
     }
     return -1;
 }

 int ff_amf_get_field_value(const uint8_t *data, const uint8_t *data_end,
                            const uint8_t *name, uint8_t *dst, int dst_size)
 {
     GetByteContext gb;
 
     if (data >= data_end)
         return -1;
 
     bytestream2_init(&gb, data, data_end - data);
 
     return amf_get_field_value2(&gb, name, dst, dst_size);
 }
 

 static const char* rtmp_packet_type(int type)
 {
     switch (type) {
     case RTMP_PT_CHUNK_SIZE:     return "chunk size";
     case RTMP_PT_BYTES_READ:     return "bytes read";

     case RTMP_PT_USER_CONTROL:   return "user control";
     case RTMP_PT_WINDOW_ACK_SIZE: return "window acknowledgement size";
     case RTMP_PT_SET_PEER_BW:    return "set peer bandwidth";

     case RTMP_PT_AUDIO:          return "audio packet";
     case RTMP_PT_VIDEO:          return "video packet";
     case RTMP_PT_FLEX_STREAM:    return "Flex shared stream";
     case RTMP_PT_FLEX_OBJECT:    return "Flex shared object";
     case RTMP_PT_FLEX_MESSAGE:   return "Flex shared message";
     case RTMP_PT_NOTIFY:         return "notification";
     case RTMP_PT_SHARED_OBJ:     return "shared object";
     case RTMP_PT_INVOKE:         return "invoke";
     case RTMP_PT_METADATA:       return "metadata";
     default:                     return "unknown";
     }
 }
 

 static void amf_tag_contents(void *ctx, const uint8_t *data,
                              const uint8_t *data_end)

 {

     unsigned int size, nb = -1;

     char buf[1024];

     AMFDataType type;
     int parse_key = 1;

 
     if (data >= data_end)
         return;

     switch ((type = *data++)) {

     case AMF_DATA_TYPE_NUMBER:

         av_log(ctx, AV_LOG_DEBUG, " number %g\n", av_int2double(AV_RB64(data)));

         return;
     case AMF_DATA_TYPE_BOOL:
         av_log(ctx, AV_LOG_DEBUG, " bool %d\n", *data);
         return;
     case AMF_DATA_TYPE_STRING:
     case AMF_DATA_TYPE_LONG_STRING:

         if (type == AMF_DATA_TYPE_STRING) {

             size = bytestream_get_be16(&data);
         } else {

             size = bytestream_get_be32(&data);

         }

         size = FFMIN(size, sizeof(buf) - 1);

         memcpy(buf, data, size);
         buf[size] = 0;
         av_log(ctx, AV_LOG_DEBUG, " string '%s'\n", buf);
         return;
     case AMF_DATA_TYPE_NULL:
         av_log(ctx, AV_LOG_DEBUG, " NULL\n");
         return;
     case AMF_DATA_TYPE_ARRAY:

         parse_key = 0;
     case AMF_DATA_TYPE_MIXEDARRAY:
         nb = bytestream_get_be32(&data);

     case AMF_DATA_TYPE_OBJECT:
         av_log(ctx, AV_LOG_DEBUG, " {\n");

         while (nb-- > 0 || type != AMF_DATA_TYPE_ARRAY) {

             int t;

             if (parse_key) {
                 size = bytestream_get_be16(&data);
                 size = FFMIN(size, sizeof(buf) - 1);
                 if (!size) {
                     av_log(ctx, AV_LOG_DEBUG, " }\n");
                     data++;
                     break;
                 }
                 memcpy(buf, data, size);
                 buf[size] = 0;
                 if (size >= data_end - data)
                     return;
                 data += size;
                 av_log(ctx, AV_LOG_DEBUG, "  %s: ", buf);

             }

             amf_tag_contents(ctx, data, data_end);

             t = ff_amf_tag_size(data, data_end);

             if (t < 0 || t >= data_end - data)

                 return;
             data += t;
         }
         return;
     case AMF_DATA_TYPE_OBJECT_END:
         av_log(ctx, AV_LOG_DEBUG, " }\n");
         return;
     default:
         return;
     }
 }
 
 void ff_rtmp_packet_dump(void *ctx, RTMPPacket *p)
 {
     av_log(ctx, AV_LOG_DEBUG, "RTMP packet type '%s'(%d) for channel %d, timestamp %d, extra field %d size %d\n",

            rtmp_packet_type(p->type), p->type, p->channel_id, p->timestamp, p->extra, p->size);

     if (p->type == RTMP_PT_INVOKE || p->type == RTMP_PT_NOTIFY) {

         uint8_t *src = p->data, *src_end = p->data + p->size;

         while (src < src_end) {
             int sz;

             amf_tag_contents(ctx, src, src_end);

             sz = ff_amf_tag_size(src, src_end);
             if (sz < 0)
                 break;
             src += sz;
         }

     } else if (p->type == RTMP_PT_WINDOW_ACK_SIZE) {
         av_log(ctx, AV_LOG_DEBUG, "Window acknowledgement size = %d\n", AV_RB32(p->data));
     } else if (p->type == RTMP_PT_SET_PEER_BW) {
         av_log(ctx, AV_LOG_DEBUG, "Set Peer BW = %d\n", AV_RB32(p->data));

     } else if (p->type != RTMP_PT_AUDIO && p->type != RTMP_PT_VIDEO && p->type != RTMP_PT_METADATA) {
         int i;

         for (i = 0; i < p->size; i++)

             av_log(ctx, AV_LOG_DEBUG, " %02X", p->data[i]);
         av_log(ctx, AV_LOG_DEBUG, "\n");
     }
 }

 
 int ff_amf_match_string(const uint8_t *data, int size, const char *str)
 {
     int len = strlen(str);
     int amf_len, type;
 
     if (size < 1)
         return 0;
 
     type = *data++;
 
     if (type != AMF_DATA_TYPE_LONG_STRING &&
         type != AMF_DATA_TYPE_STRING)
         return 0;
 
     if (type == AMF_DATA_TYPE_LONG_STRING) {
         if ((size -= 4 + 1) < 0)
             return 0;
         amf_len = bytestream_get_be32(&data);
     } else {
         if ((size -= 2 + 1) < 0)
             return 0;
         amf_len = bytestream_get_be16(&data);
     }
 
     if (amf_len > size)
         return 0;
 
     if (amf_len != len)
         return 0;
 
     return !memcmp(data, str, len);
 }