FreeCalypso > hg > sipout-test-utils

comparison test-v22/rtp_rx.c @ 10:3c5734b88c20

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sipout-test-v22 put together
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 07 Mar 2024 02:33:49 -0800
parents test-fsk/rtp_rx.c@eaf0e8f81a22
children
comparison
equal deleted inserted replaced
9:ff535725e01f 10:3c5734b88c20
1 /*
2 * In this module we implement our RTP handling: obtaining a PSTN-side
3 * RTP endpoint from themwi-rtp-mgr, then handling read select on RTP
4 * and RTCP UDP sockets.
5 */
6
7 #include <sys/types.h>
8 #include <sys/socket.h>
9 #include <netinet/in.h>
10 #include <stdio.h>
11 #include <stdint.h>
12 #include <stdlib.h>
13 #include <string.h>
14 #include <strings.h>
15 #include "../include/tmgw_const.h"
16 #include "../include/rtp_defs.h"
17 #include "../include/pstn_defs.h"
18 #include "../librtpalloc/rtp_alloc_simple.h"
19
20 extern const uint16_t pcmu_decode_table[256];
21 extern const uint16_t pcma_decode_table[256];
22
23 extern int rtp_out_enable; /* misusing the flag :-( */
24
25 struct sockaddr_in rtp_local_addr;
26 int rtp_udp_fd, rtcp_udp_fd;
27
28 static int rtp_start_flag, rtp_bad_flag, rtp_ssrc_chg_flag;
29 static int rtp_seq_brk_flag, rtp_seq_zero_flag, rtp_seq_neg_flag;
30 static int rtp_ts_brk_flag;
31 static uint32_t rtp_ssrc;
32 static uint32_t rtp_last_ts;
33 static uint16_t rtp_last_seq;
34 static int got_some_rtcp;
35
36 void
37 obtain_rtp_endp()
38 {
39 int rc;
40 struct rtp_alloc_simple res;
41
42 rc = rtp_alloc_simple(TMGW_EP_TYPE_PSTN_ONLY, &res);
43 if (rc < 0)
44 exit(1); /* error msg already printed */
45 bcopy(&res.pstn_addr, &rtp_local_addr, sizeof(struct sockaddr_in));
46 rtp_udp_fd = res.pstn_rtp_fd;
47 rtcp_udp_fd = res.pstn_rtcp_fd;
48 }
49
50 void
51 rtp_rx_select()
52 {
53 struct rtp_packet pkt;
54 struct sockaddr_in sin_from;
55 socklen_t addrlen;
56 int16_t seq_delta;
57 int32_t ts_delta;
58 const uint16_t *pcm_dec_table;
59 int16_t pcm_samples[FRAME_20MS];
60 unsigned n;
61 int rc;
62
63 addrlen = sizeof(struct sockaddr_in);
64 rc = recvfrom(rtp_udp_fd, &pkt, sizeof pkt, 0,
65 (struct sockaddr *) &sin_from, &addrlen);
66 if (rc < 0)
67 return;
68 if (rc != RTP_PACKET_SIZE_PSTN) {
69 bad_rtp_pkt: if (!rtp_bad_flag) {
70 printf("Got a bad RTP packet\n");
71 rtp_bad_flag = 1;
72 }
73 return;
74 }
75 if (pkt.v_p_x_cc != 0x80)
76 goto bad_rtp_pkt;
77 switch (pkt.m_pt & 0x7F) {
78 case PSTN_CODEC_PCMU:
79 pcm_dec_table = pcmu_decode_table;
80 break;
81 case PSTN_CODEC_PCMA:
82 pcm_dec_table = pcma_decode_table;
83 break;
84 default:
85 goto bad_rtp_pkt;
86 }
87 if (rtp_start_flag && pkt.ssrc != rtp_ssrc) {
88 if (!rtp_ssrc_chg_flag) {
89 printf("Rx RTP stream changed SSRC\n");
90 rtp_ssrc_chg_flag = 1;
91 }
92 } else if (rtp_start_flag) {
93 seq_delta = ntohs(pkt.seq) - rtp_last_seq;
94 ts_delta = ntohl(pkt.tstamp) - rtp_last_ts;
95 if (seq_delta == 0) {
96 if (!rtp_seq_zero_flag) {
97 printf("Rx RTP seq zero increment\n");
98 rtp_seq_zero_flag = 1;
99 }
100 return;
101 }
102 if (seq_delta < 0) {
103 if (!rtp_seq_neg_flag) {
104 printf("Rx RTP seq negative increment\n");
105 rtp_seq_neg_flag = 1;
106 }
107 return;
108 }
109 if (seq_delta != 1) {
110 if (!rtp_seq_brk_flag) {
111 printf("Rx RTP stream seq break\n");
112 rtp_seq_brk_flag = 1;
113 }
114 } else if (ts_delta != 160) {
115 if (!rtp_ts_brk_flag) {
116 printf("Rx RTP stream tstamp break\n");
117 rtp_ts_brk_flag = 1;
118 }
119 }
120 }
121 rtp_ssrc = pkt.ssrc;
122 rtp_last_ts = ntohl(pkt.tstamp);
123 rtp_last_seq = ntohs(pkt.seq);
124 if (!rtp_start_flag) {
125 printf("Rx RTP stream begins with seq=%u ts=%u\n",
126 rtp_last_seq, rtp_last_ts);
127 rtp_start_flag = 1;
128 }
129 /* ignore early RTP during ringing, before answer supervision */
130 if (!rtp_out_enable)
131 return;
132 /* feed samples to modem Rx */
133 for (n = 0; n < FRAME_20MS; n++)
134 pcm_samples[n] = pcm_dec_table[pkt.payload[n]];
135 process_rx_frame(pcm_samples);
136 }
137
138 void
139 rtcp_rx_select()
140 {
141 u_char buf[512];
142
143 recv(rtcp_udp_fd, buf, sizeof buf, 0);
144 if (!got_some_rtcp) {
145 printf("Got some RTCP\n");
146 got_some_rtcp = 1;
147 }
148 }