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#include <u.h>
#include <libc.h>
#include <ip.h>
#include "dat.h"
#include "protos.h"
typedef struct Hdr Hdr;
struct Hdr {
uchar hdr; /* RTP header */
uchar marker; /* Payload and marker */
uchar seq[2]; /* Sequence number */
uchar ts[4]; /* Time stamp */
uchar ssrc[4]; /* Synchronization source identifier */
};
enum{
RTPLEN = 12, /* Minimum size of an RTP header */
};
static int
p_seprint(Msg *m)
{
Hdr*h;
ushort seq;
ulong ssrc, ts;
int cc, i;
if(m->pe - m->ps < RTPLEN)
return -1;
h = (Hdr*)m->ps;
cc = h->hdr & 0xf;
if(m->pe - m->ps < RTPLEN + cc * 4)
return -1;
m->ps += RTPLEN;
seq = NetS(h->seq);
ts = NetL(h->ts);
ssrc = NetL(h->ssrc);
m->p = seprint(m->p, m->e, "version=%d x=%d cc=%d seq=%d ts=%ld ssrc=%ulx",
(h->hdr >> 6) & 3, (h->hdr >> 4) & 1, cc, seq, ts, ssrc);
for(i = 0; i < cc; i++){
m->p = seprint(m->p, m->e, " csrc[%d]=%d",
i, NetL(m->ps));
m->ps += 4;
}
m->pr = nil;
return 0;
}
Proto rtp = {
"rtp",
nil,
nil,
p_seprint,
nil,
nil,
nil,
defaultframer
};
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