code.delx.au - pulseaudio/blob - src/modules/rtp/rtp.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of polypaudio.
   5
   6   polypaudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2 of the License,
   9   or (at your option) any later version.
  10
  11   polypaudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with polypaudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <assert.h>
  27 #include <fcntl.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <errno.h>
  31 #include <arpa/inet.h>
  32 #include <unistd.h>
  33
  34 #include <polypcore/log.h>
  35
  36 #include "rtp.h"
  37
  38 pa_rtp_context* pa_rtp_context_init_send(pa_rtp_context *c, int fd, uint32_t ssrc, uint8_t payload, size_t frame_size) {
  39     assert(c);
  40     assert(fd >= 0);
  41
  42     c->fd = fd;
  43     c->sequence = (uint16_t) (rand()*rand());
  44     c->timestamp = 0;
  45     c->ssrc = ssrc ? ssrc : (uint32_t) (rand()*rand());
  46     c->payload = payload & 127;
  47     c->frame_size = frame_size;
  48
  49     return c;
  50 }
  51
  52 #define MAX_IOVECS 16
  53
  54 int pa_rtp_send(pa_rtp_context *c, size_t size, pa_memblockq *q) {
  55     struct iovec iov[MAX_IOVECS];
  56     pa_memblock* mb[MAX_IOVECS];
  57     int iov_idx = 1;
  58     size_t n = 0, skip = 0;
  59
  60     assert(c);
  61     assert(size > 0);
  62     assert(q);
  63
  64     if (pa_memblockq_get_length(q) < size)
  65         return 0;
  66
  67     for (;;) {
  68         int r;
  69         pa_memchunk chunk;
  70
  71         if ((r = pa_memblockq_peek(q, &chunk)) >= 0) {
  72
  73             size_t k = n + chunk.length > size ? size - n : chunk.length;
  74
  75             if (chunk.memblock) {
  76                 iov[iov_idx].iov_base = (uint8_t*) chunk.memblock->data + chunk.index;
  77                 iov[iov_idx].iov_len = k;
  78                 mb[iov_idx] = chunk.memblock;
  79                 iov_idx ++;
  80
  81                 n += k;
  82             }
  83
  84             skip += k;
  85             pa_memblockq_drop(q, &chunk, k);
  86         }
  87
  88         if (r < 0 || !chunk.memblock || n >= size || iov_idx >= MAX_IOVECS) {
  89             uint32_t header[3];
  90             struct msghdr m;
  91             int k, i;
  92
  93             if (n > 0) {
  94                 header[0] = htonl(((uint32_t) 2 << 30) | ((uint32_t) c->payload << 16) | ((uint32_t) c->sequence));
  95                 header[1] = htonl(c->timestamp);
  96                 header[2] = htonl(c->ssrc);
  97
  98                 iov[0].iov_base = header;
  99                 iov[0].iov_len = sizeof(header);
 100
 101                 m.msg_name = NULL;
 102                 m.msg_namelen = 0;
 103                 m.msg_iov = iov;
 104                 m.msg_iovlen = iov_idx;
 105                 m.msg_control = NULL;
 106                 m.msg_controllen = 0;
 107                 m.msg_flags = 0;
 108
 109                 k = sendmsg(c->fd, &m, MSG_DONTWAIT);
 110
 111                 for (i = 1; i < iov_idx; i++)
 112                     pa_memblock_unref(mb[i]);
 113
 114                 c->sequence++;
 115             } else
 116                 k = 0;
 117
 118             c->timestamp += skip/c->frame_size;
 119
 120             if (k < 0) {
 121                 if (errno != EAGAIN) /* If the queue is full, just ignore it */
 122                     pa_log(__FILE__": sendmsg() failed: %s", strerror(errno));
 123                 return -1;
 124             }
 125
 126             if (r < 0 || pa_memblockq_get_length(q) < size)
 127                 break;
 128
 129             n = 0;
 130             skip = 0;
 131             iov_idx = 1;
 132         }
 133     }
 134
 135     return 0;
 136 }
 137
 138 pa_rtp_context* pa_rtp_context_init_recv(pa_rtp_context *c, int fd) {
 139     assert(c);
 140
 141     c->fd = fd;
 142     return c;
 143 }
 144
 145 int pa_rtp_recv(pa_rtp_context *c, pa_memchunk *chunk) {
 146     assert(c);
 147     assert(chunk);
 148
 149     return 0;
 150 }
 151
 152 uint8_t pa_rtp_payload_type(const pa_sample_spec *ss) {
 153     assert(ss);
 154
 155     if (ss->format == PA_SAMPLE_ULAW && ss->rate == 8000 && ss->channels == 1)
 156         return 0;
 157     if (ss->format == PA_SAMPLE_ALAW && ss->rate == 8000 && ss->channels == 1)
 158         return 0;
 159     if (ss->format == PA_SAMPLE_S16BE && ss->rate == 44100 && ss->channels == 2)
 160         return 10;
 161     if (ss->format == PA_SAMPLE_S16BE && ss->rate == 44100 && ss->channels == 1)
 162         return 11;
 163
 164     return 127;
 165 }
 166
 167 pa_sample_spec *pa_rtp_sample_spec_fixup(pa_sample_spec * ss) {
 168     assert(ss);
 169
 170     if (!pa_rtp_sample_spec_valid(ss))
 171         ss->format = PA_SAMPLE_S16BE;
 172
 173     assert(pa_rtp_sample_spec_valid(ss));
 174     return ss;
 175 }
 176
 177 int pa_rtp_sample_spec_valid(const pa_sample_spec *ss) {
 178     assert(ss);
 179
 180     if (!pa_sample_spec_valid(ss))
 181         return 0;
 182
 183     return
 184         ss->format == PA_SAMPLE_U8 ||
 185         ss->format == PA_SAMPLE_ALAW ||
 186         ss->format == PA_SAMPLE_ULAW ||
 187         ss->format == PA_SAMPLE_S16BE;
 188 }
 189
 190 void pa_rtp_context_destroy(pa_rtp_context *c) {
 191     assert(c);
 192
 193     close(c->fd);
 194 }