mDNSPosix/ExampleClientApp.c

   1 /* -*- Mode: C; tab-width: 4 -*-
   2  *
   3  * Copyright (c) 2002-2004 Apple Computer, Inc. All rights reserved.
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #include <stdio.h>                      // For printf()
  19 #include <stdlib.h>                     // For exit() etc.
  20 #include <string.h>                     // For strlen() etc.
  21 #include <unistd.h>                     // For select()
  22 #include <errno.h>                      // For errno, EINTR
  23 #include <netinet/in.h>         // For INADDR_NONE
  24 #include <arpa/inet.h>          // For inet_addr()
  25 #include <netdb.h>                      // For gethostbyname()
  26 #include <signal.h>                     // For SIGINT, etc.
  27
  28 #include "mDNSEmbeddedAPI.h"  // Defines the interface to the client layer above
  29 #include "mDNSPosix.h"      // Defines the specific types needed to run mDNS on this platform
  30
  31 //*******************************************************************************************
  32 // Main
  33
  34 static volatile mDNSBool StopNow;
  35
  36 mDNSlocal void HandleSIG(int signal)
  37         {
  38         (void)signal;   // Unused
  39         debugf("%s","");
  40         debugf("HandleSIG");
  41         StopNow = mDNStrue;
  42         }
  43
  44 mDNSexport void ExampleClientEventLoop(mDNS *const m)
  45         {
  46         signal(SIGINT, HandleSIG);      // SIGINT is what you get for a Ctrl-C
  47         signal(SIGTERM, HandleSIG);
  48
  49         while (!StopNow)
  50                 {
  51                 int nfds = 0;
  52                 fd_set readfds;
  53                 struct timeval timeout;
  54                 int result;
  55
  56                 // 1. Set up the fd_set as usual here.
  57                 // This example client has no file descriptors of its own,
  58                 // but a real application would call FD_SET to add them to the set here
  59                 FD_ZERO(&readfds);
  60
  61                 // 2. Set up the timeout.
  62                 // This example client has no other work it needs to be doing,
  63                 // so we set an effectively infinite timeout
  64                 timeout.tv_sec = 0x3FFFFFFF;
  65                 timeout.tv_usec = 0;
  66
  67                 // 3. Give the mDNSPosix layer a chance to add its information to the fd_set and timeout
  68                 mDNSPosixGetFDSet(m, &nfds, &readfds, &timeout);
  69
  70                 // 4. Call select as normal
  71                 verbosedebugf("select(%d, %d.%06d)", nfds, timeout.tv_sec, timeout.tv_usec);
  72                 result = select(nfds, &readfds, NULL, NULL, &timeout);
  73
  74                 if (result < 0)
  75                         {
  76                         verbosedebugf("select() returned %d errno %d", result, errno);
  77                         if (errno != EINTR) StopNow = mDNStrue;
  78                         }
  79                 else
  80                         {
  81                         // 5. Call mDNSPosixProcessFDSet to let the mDNSPosix layer do its work
  82                         mDNSPosixProcessFDSet(m, &readfds);
  83
  84                         // 6. This example client has no other work it needs to be doing,
  85                         // but a real client would do its work here
  86                         // ... (do work) ...
  87                         }
  88                 }
  89
  90         debugf("Exiting");
  91         }