comm.c

   1 /*****************************************************************************
   2  * comm.c: Handles the communication socket (linux-dvb only)
   3  *****************************************************************************
   4  * Copyright (C) 2008 VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Christophe Massiot <massiot@via.ecp.fr>
   8  *
   9  * This program is free software. It comes without any warranty, to
  10  * the extent permitted by applicable law. You can redistribute it
  11  * and/or modify it under the terms of the Do What The Fuck You Want
  12  * To Public License, Version 2, as published by Sam Hocevar. See
  13  * http://sam.zoy.org/wtfpl/COPYING for more details.
  14  *****************************************************************************/
  15
  16 #include <stdlib.h>
  17 #include <stdio.h>
  18 #include <unistd.h>
  19 #include <stdint.h>
  20 #include <stdbool.h>
  21 #include <string.h>
  22 #include <sys/types.h>
  23 #include <sys/stat.h>
  24 #include <sys/socket.h>
  25 #include <netinet/in.h>
  26 #include <arpa/inet.h>
  27 #include <sys/un.h>
  28 #include <errno.h>
  29
  30 #include "dvblast.h"
  31 #include "en50221.h"
  32 #include "comm.h"
  33
  34 /*****************************************************************************
  35  * Local declarations
  36  *****************************************************************************/
  37 int i_comm_fd = -1;
  38
  39 /*****************************************************************************
  40  * comm_Open
  41  *****************************************************************************/
  42 void comm_Open( void )
  43 {
  44     int i_size = 65535;
  45     struct sockaddr_un sun_server;
  46
  47     if ( (i_comm_fd = socket( AF_UNIX, SOCK_DGRAM, 0 )) == -1 )
  48     {
  49         msg_Err( NULL, "cannot create comm socket (%s)", strerror(errno) );
  50         return;
  51     }
  52
  53     setsockopt( i_comm_fd, SOL_SOCKET, SO_RCVBUF, &i_size, sizeof(i_size) );
  54
  55     memset( &sun_server, 0, sizeof(sun_server) );
  56     sun_server.sun_family = AF_UNIX;
  57     strncpy( sun_server.sun_path, psz_srv_socket, sizeof(sun_server.sun_path) );
  58     sun_server.sun_path[sizeof(sun_server.sun_path) - 1] = '\0';
  59
  60     if ( bind( i_comm_fd, (struct sockaddr *)&sun_server,
  61                SUN_LEN(&sun_server) ) < 0 )
  62     {
  63         msg_Err( NULL, "cannot bind comm socket (%s)", strerror(errno) );
  64         close( i_comm_fd );
  65         i_comm_fd = -1;
  66         return;
  67     }
  68 }
  69
  70 /*****************************************************************************
  71  * comm_Read
  72  *****************************************************************************/
  73 void comm_Read( void )
  74 {
  75     struct sockaddr_un sun_client;
  76     socklen_t sun_length = sizeof(sun_client);
  77     ssize_t i_size, i_answer_size = 0;
  78     uint8_t p_buffer[COMM_BUFFER_SIZE], p_answer[COMM_BUFFER_SIZE];
  79     uint8_t i_command, i_answer;
  80
  81     i_size = recvfrom( i_comm_fd, p_buffer, COMM_BUFFER_SIZE, 0,
  82                        (struct sockaddr *)&sun_client, &sun_length );
  83     if ( i_size < COMM_HEADER_SIZE )
  84     {
  85         msg_Err( NULL, "cannot read comm socket (%d:%s)\n", i_size,
  86                  strerror(errno) );
  87         return;
  88     }
  89     if ( sun_length == 0 || sun_length > sizeof(sun_client) )
  90     {
  91         msg_Err( NULL, "anonymous packet from comm socket\n" );
  92         return;
  93     }
  94
  95     if ( p_buffer[0] != COMM_HEADER_MAGIC )
  96     {
  97         msg_Err( NULL, "wrong protocol version 0x%x", p_buffer[0] );
  98         return;
  99     }
 100
 101     i_command = p_buffer[1];
 102
 103     switch ( i_command )
 104     {
 105     case CMD_RELOAD:
 106         b_hup_received = 1;
 107         i_answer = RET_OK;
 108         i_answer_size = 0;
 109         break;
 110
 111     case CMD_FRONTEND_STATUS:
 112         i_answer = dvb_FrontendStatus( p_answer + COMM_HEADER_SIZE,
 113                                        &i_answer_size );
 114         break;
 115
 116     case CMD_MMI_STATUS:
 117         i_answer = en50221_StatusMMI( p_answer + COMM_HEADER_SIZE,
 118                                       &i_answer_size );
 119         break;
 120
 121     case CMD_MMI_SLOT_STATUS:
 122         i_answer = en50221_StatusMMISlot( p_buffer + COMM_HEADER_SIZE,
 123                                           i_size - COMM_HEADER_SIZE,
 124                                           p_answer + COMM_HEADER_SIZE,
 125                                           &i_answer_size );
 126         break;
 127
 128     case CMD_MMI_OPEN:
 129         i_answer = en50221_OpenMMI( p_buffer + COMM_HEADER_SIZE,
 130                                     i_size - COMM_HEADER_SIZE );
 131         break;
 132
 133     case CMD_MMI_CLOSE:
 134         i_answer = en50221_CloseMMI( p_buffer + COMM_HEADER_SIZE,
 135                                      i_size - COMM_HEADER_SIZE );
 136         break;
 137
 138     case CMD_MMI_RECV:
 139         i_answer = en50221_GetMMIObject( p_buffer + COMM_HEADER_SIZE,
 140                                          i_size - COMM_HEADER_SIZE,
 141                                          p_answer + COMM_HEADER_SIZE,
 142                                          &i_answer_size );
 143         break;
 144
 145     case CMD_MMI_SEND:
 146         i_answer = en50221_SendMMIObject( p_buffer + COMM_HEADER_SIZE,
 147                                           i_size - COMM_HEADER_SIZE );
 148         break;
 149
 150     case CMD_SHUTDOWN:
 151         msg_Err( NULL, "shutdown via comm" );
 152         exit(EXIT_SUCCESS);
 153         /* this is a bit violent, but hey, closing everything cleanly
 154          * would do approximately the same */
 155
 156     default:
 157         msg_Err( NULL, "wrong command %u", i_command );
 158         i_answer = RET_HUH;
 159         i_answer_size = 0;
 160         break;
 161     }
 162
 163     p_answer[0] = COMM_HEADER_MAGIC;
 164     p_answer[1] = i_answer;
 165     p_answer[2] = 0;
 166     p_answer[3] = 0;
 167     msg_Dbg( NULL, "answering %d to %d with size %d", i_answer, i_command,
 168              i_answer_size );
 169
 170     if ( sendto( i_comm_fd, p_answer, i_answer_size + COMM_HEADER_SIZE, 0,
 171                  (struct sockaddr *)&sun_client, sun_length ) < 0 )
 172         msg_Err( NULL, "cannot send comm socket (%s)", strerror(errno) );
 173 }