re/src/rtp/sdes.c
2011-03-01 11:11:08 +00:00

148 lines
2.7 KiB
C

/**
* @file sdes.c RTCP Source Description
*
* Copyright (C) 2010 Creytiv.com
*/
#include <string.h>
#include <re_types.h>
#include <re_fmt.h>
#include <re_mem.h>
#include <re_mbuf.h>
#include <re_list.h>
#include <re_sa.h>
#include <re_rtp.h>
#include "rtcp.h"
#define DEBUG_MODULE "rtcp_sdes"
#define DEBUG_LEVEL 5
#include <re_dbg.h>
enum {
RTCP_SDES_MIN_SIZE = 1,
};
/**
* Encode one SDES chunk into mbuffer
*
* @param mb Buffer to encode into
* @param src First SSRC/CSRC
* @param itemc Number of SDES items to encode
*
* @return 0 if success, otherwise errorcode
*/
int rtcp_sdes_encode(struct mbuf *mb, uint32_t src, uint32_t itemc, ...)
{
va_list ap;
size_t start;
int err = 0;
if (!mb || !itemc)
return EINVAL;
va_start(ap, itemc);
start = mb->pos;
err = mbuf_write_u32(mb, htonl(src));
/* add all SDES items */
while (itemc-- && !err) {
const uint8_t type = va_arg(ap, int);
const char *v = va_arg(ap, const char *);
size_t len;
if (!v)
continue;
len = strlen(v); /* note: max 255 chars */
if (len > 255) {
err = EINVAL;
goto out;
}
err = mbuf_write_u8(mb, type);
err |= mbuf_write_u8(mb, len & 0xff);
err |= mbuf_write_mem(mb, (uint8_t *)v, len);
}
/* END padding */
err |= mbuf_write_u8(mb, RTCP_SDES_END);
while ((mb->pos - start) & 0x3)
err |= mbuf_write_u8(mb, RTCP_SDES_END);
out:
va_end(ap);
return err;
}
/**
* Decode SDES items from a buffer
*
* @param mb Buffer to decode from
* @param sdes RTCP SDES to decode into
*
* @return 0 if success, otherwise errorcode
*/
int rtcp_sdes_decode(struct mbuf *mb, struct rtcp_sdes *sdes)
{
size_t start;
if (!sdes)
return EINVAL;
if (mbuf_get_left(mb) < RTCP_SRC_SIZE)
return EBADMSG;
start = mb->pos;
sdes->src = ntohl(mbuf_read_u32(mb));
/* Decode all SDES items */
while (mbuf_get_left(mb) >= RTCP_SDES_MIN_SIZE) {
uint8_t type;
struct rtcp_sdes_item *item;
type = mbuf_read_u8(mb);
if (type == RTCP_SDES_END)
break;
if (mbuf_get_left(mb) < 1)
return EBADMSG;
if (!sdes->itemv) {
sdes->itemv = mem_alloc(sizeof(*sdes->itemv), NULL);
if (!sdes->itemv)
return ENOMEM;
}
else {
const size_t sz = (sdes->n + 1) * sizeof(*sdes->itemv);
struct rtcp_sdes_item *itemv;
itemv = mem_realloc(sdes->itemv, sz);
if (!itemv)
return ENOMEM;
sdes->itemv = itemv;
}
item = &sdes->itemv[sdes->n];
item->type = (enum rtcp_sdes_type)type;
item->length = mbuf_read_u8(mb);
if (mbuf_get_left(mb) < item->length)
return EBADMSG;
item->data = mem_alloc(item->length, NULL);
if (!item->data)
return ENOMEM;
(void)mbuf_read_mem(mb, (uint8_t *)item->data, item->length);
sdes->n++;
}
/* slurp padding */
while ((mb->pos - start) & 0x3 && mbuf_get_left(mb))
++mb->pos;
return 0;
}