udp_recv.c

   1 /*
   2  * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6 /** \file udp_recv.c Paraslash's udp receiver */
   7
   8 #include <dirent.h>
   9
  10 #include "para.h"
  11 #include "portable_io.h"
  12 #include "udp_header.h"
  13 #include "list.h"
  14 #include "sched.h"
  15 #include "ggo.h"
  16 #include "recv.h"
  17 #include "udp_recv.cmdline.h"
  18 #include "error.h"
  19 #include "audiod.h"
  20 #include "string.h"
  21 #include "net.h"
  22 #include "fd.h"
  23
  24 /** The size of the receiver node buffer. */
  25 #define UDP_RECV_CHUNK_SIZE (128 * 1024)
  26
  27 /**
  28  * Data specific to the udp receiver.
  29  *
  30  * \sa \ref receiver, \ref receiver_node.
  31  */
  32 struct private_udp_recv_data {
  33         /**
  34          * Whether a header was received.
  35          *
  36          * A flag indicating whether this receiver already received a packet
  37          * which contains the audio file header.
  38          *
  39          * This flag has no effect if the audio stream indicates that no extra
  40          * headers will be sent (mp3, aac).  Otherwise, all data packets are
  41          * dropped until the header is received.
  42          */
  43         int have_header;
  44         /** The socket file descriptor. */
  45         int fd;
  46 };
  47
  48 static void udp_recv_pre_select(struct sched *s, struct task *t)
  49 {
  50         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  51         struct private_udp_recv_data *purd = rn->private_data;
  52
  53         para_fd_set(purd->fd, &s->rfds, &s->max_fileno);
  54 }
  55
  56 static int enough_space(size_t nbytes, size_t loaded)
  57 {
  58         return nbytes + loaded < UDP_RECV_CHUNK_SIZE;
  59 }
  60
  61 static void udp_recv_post_select(__a_unused struct sched *s, struct task *t)
  62 {
  63         struct receiver_node *rn = container_of(t, struct receiver_node, task);
  64         struct private_udp_recv_data *purd = rn->private_data;
  65         int ret;
  66         char tmpbuf[UDP_RECV_CHUNK_SIZE];
  67         size_t packet_size;
  68         uint8_t stream_type, packet_type;
  69
  70         if (rn->output_error && *rn->output_error < 0) {
  71                 t->error = *rn->output_error;
  72                 return;
  73         }
  74         if (!FD_ISSET(purd->fd, &s->rfds))
  75                 return;
  76         ret = recv_bin_buffer(purd->fd, tmpbuf, UDP_RECV_CHUNK_SIZE);
  77         if (ret < 0) {
  78                 if (is_errno(ret, EINTR) || is_errno(ret, EAGAIN))
  79                         goto success;
  80                 t->error = ret;
  81                 return;
  82         }
  83         t->error = -E_RECV_EOF;
  84         if (!ret)
  85                 return;
  86         packet_size = ret;
  87         t->error = -E_UDP_SHORT_PACKET;
  88         if (packet_size < UDP_AUDIO_HEADER_LEN)
  89                 return;
  90         t->error = -E_UDP_NO_MAGIC;
  91         if (udp_check_magic(tmpbuf, packet_size) < 0)
  92                 return;
  93         stream_type = udp_read_stream_type(tmpbuf);
  94         packet_type = udp_read_packet_type(tmpbuf);
  95 //      PARA_INFO_LOG("packet type: %d, stream type: %d,"
  96 //              " loaded: %u\n", packet_type,
  97 //              (unsigned) stream_type, rn->loaded);
  98         switch (packet_type) {
  99                 uint16_t header_len, payload_len;
 100
 101         case UDP_EOF_PACKET:
 102                 t->error = -E_RECV_EOF;
 103                 return;
 104         case UDP_BOF_PACKET:
 105                 PARA_INFO_LOG("bof (%zu)\n", packet_size);
 106                 purd->have_header = 1;
 107                 /* fall through */
 108         case UDP_DATA_PACKET:
 109                 if (!purd->have_header && stream_type == UDP_HEADER_STREAM)
 110                         /* can't use the data, wait for header */
 111                         goto success;
 112                 payload_len = packet_size - UDP_AUDIO_HEADER_LEN;
 113                 if (!payload_len)
 114                         goto success;
 115                 t->error = -E_OVERRUN;
 116                 if (!enough_space(payload_len, rn->loaded))
 117                         return;
 118                 memcpy(rn->buf + rn->loaded, tmpbuf + UDP_AUDIO_HEADER_LEN,
 119                         payload_len);
 120                 rn->loaded += payload_len;
 121                 goto success;
 122         case UDP_HEADER_PACKET:
 123                 header_len = udp_read_header_len(tmpbuf);
 124                 if (header_len + UDP_AUDIO_HEADER_LEN > packet_size) {
 125                         t->error = -E_INVALID_HEADER;
 126                         return;
 127                 }
 128 //              PARA_DEBUG_LOG("header packet (%zu bytes), header len: %d\n",
 129 //                      packet_size, header_len);
 130                 if (!purd->have_header) {
 131                         t->error = -E_OVERRUN;
 132                         if (!enough_space(header_len, rn->loaded))
 133                                 return;
 134                         purd->have_header = 1;
 135                         rn->loaded = header_len;
 136                         memcpy(rn->buf, tmpbuf + UDP_AUDIO_HEADER_LEN,
 137                                 rn->loaded);
 138                         goto success;
 139                 }
 140                 payload_len = packet_size - UDP_AUDIO_HEADER_LEN - header_len;
 141                 if (!payload_len)
 142                         goto success;
 143                 t->error = -E_OVERRUN;
 144                 if (!enough_space(payload_len, rn->loaded))
 145                         return;
 146                 memcpy(rn->buf + rn->loaded, tmpbuf + UDP_AUDIO_HEADER_LEN +
 147                         header_len, payload_len);
 148                 rn->loaded += payload_len;
 149         }
 150 success:
 151         t->error = 0;
 152 }
 153
 154 static void udp_shutdown(void)
 155 {
 156         return;
 157 }
 158
 159 static void udp_recv_close(struct receiver_node *rn)
 160 {
 161         struct private_udp_recv_data *purd = rn->private_data;
 162
 163         if (purd->fd >= 0)
 164                 close(purd->fd);
 165         free(rn->private_data);
 166         free(rn->buf);
 167 }
 168
 169 static void *udp_recv_parse_config(int argc, char **argv)
 170 {
 171         int ret;
 172         struct udp_recv_args_info *tmp =
 173                 para_calloc(sizeof(struct udp_recv_args_info));
 174
 175         ret = udp_recv_cmdline_parser(argc, argv, tmp)? -E_UDP_SYNTAX : 1;
 176         if (ret >= 0)
 177                 return tmp;
 178         free(tmp);
 179         return NULL;
 180 }
 181
 182 static int udp_recv_open(struct receiver_node *rn)
 183 {
 184         struct private_udp_recv_data *purd;
 185         struct udp_recv_args_info *c = rn->conf;
 186         int ret;
 187
 188         rn->buf = para_calloc(UDP_RECV_CHUNK_SIZE);
 189         rn->private_data = para_calloc(sizeof(struct private_udp_recv_data));
 190         purd = rn->private_data;
 191         ret = create_udp_recv_socket(c->host_arg, c->port_arg);
 192         if (ret < 0)
 193                 return ret;
 194         purd->fd = ret;
 195         ret = mark_fd_nonblocking(purd->fd);
 196         if (ret < 0)
 197                 return ret;
 198         PARA_NOTICE_LOG("receiving from %s:%d, fd=%d\n", c->host_arg,
 199                 c->port_arg, purd->fd);
 200         return purd->fd;
 201 }
 202
 203 /**
 204  * The init function of the udp receiver.
 205  *
 206  * \param r Pointer to the receiver struct to initialize.
 207  *
 208  * Initialize all function pointers of \a r.
 209  */
 210 void udp_recv_init(struct receiver *r)
 211 {
 212         struct udp_recv_args_info dummy;
 213
 214         udp_recv_cmdline_parser_init(&dummy);
 215         r->shutdown = udp_shutdown;
 216         r->open = udp_recv_open;
 217         r->close = udp_recv_close;
 218         r->pre_select = udp_recv_pre_select;
 219         r->post_select = udp_recv_post_select;
 220         r->parse_config = udp_recv_parse_config;
 221         r->help = (struct ggo_help) {
 222                 .short_help = udp_recv_args_info_help,
 223                 .detailed_help = udp_recv_args_info_detailed_help
 224         };
 225 }