mDNSPosix/ExampleClientApp.c

   1 /* -*- Mode: C; tab-width: 4 -*-
   2  *
   3  * Copyright (c) 2002-2004 Apple Computer, Inc. All rights reserved.
   4  *
   5  * @APPLE_LICENSE_HEADER_START@
   6  *
   7  * This file contains Original Code and/or Modifications of Original Code
   8  * as defined in and that are subject to the Apple Public Source License
   9  * Version 2.0 (the 'License'). You may not use this file except in
  10  * compliance with the License. Please obtain a copy of the License at
  11  * http://www.opensource.apple.com/apsl/ and read it before using this
  12  * file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  19  * Please see the License for the specific language governing rights and
  20  * limitations under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23
  24     Change History (most recent first):
  25
  26 $Log: ExampleClientApp.c,v $
  27 Revision 1.12  2004/11/30 22:37:00  cheshire
  28 Update copyright dates and add "Mode: C; tab-width: 4" headers
  29
  30 Revision 1.11  2004/09/17 01:08:53  cheshire
  31 Renamed mDNSClientAPI.h to mDNSEmbeddedAPI.h
  32   The name "mDNSClientAPI.h" is misleading to new developers looking at this code. The interfaces
  33   declared in that file are ONLY appropriate to single-address-space embedded applications.
  34   For clients on general-purpose computers, the interfaces defined in dns_sd.h should be used.
  35
  36 Revision 1.10  2004/09/16 01:58:22  cheshire
  37 Fix compiler warnings
  38
  39 Revision 1.9  2003/08/12 19:56:26  cheshire
  40 Update to APSL 2.0
  41
  42 Revision 1.8  2003/07/02 21:19:58  cheshire
  43 <rdar://problem/3313413> Update copyright notices, etc., in source code comments
  44
  45 Revision 1.7  2003/06/18 05:48:41  cheshire
  46 Fix warnings
  47
  48 Revision 1.6  2003/03/31 22:44:36  cheshire
  49 Add log header
  50
  51  */
  52
  53 #include <stdio.h>                      // For printf()
  54 #include <stdlib.h>                     // For exit() etc.
  55 #include <string.h>                     // For strlen() etc.
  56 #include <unistd.h>                     // For select()
  57 #include <errno.h>                      // For errno, EINTR
  58 #include <arpa/inet.h>          // For inet_addr()
  59 #include <netinet/in.h>         // For INADDR_NONE
  60 #include <netdb.h>                      // For gethostbyname()
  61 #include <signal.h>                     // For SIGINT, etc.
  62
  63 #include "mDNSEmbeddedAPI.h"  // Defines the interface to the client layer above
  64 #include "mDNSPosix.h"      // Defines the specific types needed to run mDNS on this platform
  65
  66 //*******************************************************************************************
  67 // Main
  68
  69 static volatile mDNSBool StopNow;
  70
  71 mDNSlocal void HandleSIG(int signal)
  72         {
  73         (void)signal;   // Unused
  74         debugf("%s","");
  75         debugf("HandleSIG");
  76         StopNow = mDNStrue;
  77         }
  78
  79 mDNSexport void ExampleClientEventLoop(mDNS *const m)
  80         {
  81         signal(SIGINT, HandleSIG);      // SIGINT is what you get for a Ctrl-C
  82         signal(SIGTERM, HandleSIG);
  83
  84         while (!StopNow)
  85                 {
  86                 int nfds = 0;
  87                 fd_set readfds;
  88                 struct timeval timeout;
  89                 int result;
  90
  91                 // 1. Set up the fd_set as usual here.
  92                 // This example client has no file descriptors of its own,
  93                 // but a real application would call FD_SET to add them to the set here
  94                 FD_ZERO(&readfds);
  95
  96                 // 2. Set up the timeout.
  97                 // This example client has no other work it needs to be doing,
  98                 // so we set an effectively infinite timeout
  99                 timeout.tv_sec = 0x3FFFFFFF;
 100                 timeout.tv_usec = 0;
 101
 102                 // 3. Give the mDNSPosix layer a chance to add its information to the fd_set and timeout
 103                 mDNSPosixGetFDSet(m, &nfds, &readfds, &timeout);
 104
 105                 // 4. Call select as normal
 106                 verbosedebugf("select(%d, %d.%06d)", nfds, timeout.tv_sec, timeout.tv_usec);
 107                 result = select(nfds, &readfds, NULL, NULL, &timeout);
 108
 109                 if (result < 0)
 110                         {
 111                         verbosedebugf("select() returned %d errno %d", result, errno);
 112                         if (errno != EINTR) StopNow = mDNStrue;
 113                         }
 114                 else
 115                         {
 116                         // 5. Call mDNSPosixProcessFDSet to let the mDNSPosix layer do its work
 117                         mDNSPosixProcessFDSet(m, &readfds);
 118
 119                         // 6. This example client has no other work it needs to be doing,
 120                         // but a real client would do its work here
 121                         // ... (do work) ...
 122                         }
 123                 }
 124
 125         debugf("Exiting");
 126         }