mDNSMacOS9/Searcher.c

   1 /*
   2  * Copyright (c) 2002-2003 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24
  25     Change History (most recent first):
  26
  27 $Log: Searcher.c,v $
  28 Revision 1.2  2004/05/27 06:30:21  cheshire
  29 Add code to test DNSServiceQueryRecord()
  30
  31 Revision 1.1  2004/03/12 21:30:25  cheshire
  32 Build a System-Context Shared Library from mDNSCore, for the benefit of developers
  33 like Muse Research who want to be able to use mDNS/DNS-SD from GPL-licensed code.
  34
  35  */
  36
  37 #include <stdio.h>                                              // For printf()
  38 #include <string.h>                                             // For strcpy()
  39
  40 #include <Events.h>                                             // For WaitNextEvent()
  41 #include <CodeFragments.h>                              // For SIOkUnresolvedCFragSymbolAddress
  42
  43 #include <SIOUX.h>                                              // For SIOUXHandleOneEvent()
  44
  45 #include <OpenTransport.h>
  46 #include <OpenTptInternet.h>
  47
  48 #include "dns_sd.h"
  49
  50 #define ns_c_in 1
  51 #define ns_t_a 1
  52
  53 typedef union { UInt8 b[2]; UInt16 NotAnInteger; } mDNSOpaque16;
  54 static UInt16 mDNSVal16(mDNSOpaque16 x) { return((UInt16)(x.b[0]<<8 | x.b[1])); }
  55 static mDNSOpaque16 mDNSOpaque16fromIntVal(UInt16 v)
  56         { mDNSOpaque16 x; x.b[0] = (UInt8)(v >> 8); x.b[1] = (UInt8)(v & 0xFF); return(x); }
  57
  58 typedef struct
  59         {
  60         OTLIFO serviceinfolist;
  61         Boolean headerPrinted;
  62         Boolean lostRecords;
  63         } SearcherServices;
  64
  65 typedef struct
  66         {
  67         SearcherServices *services;
  68         char name[kDNSServiceMaxDomainName];
  69         char type[kDNSServiceMaxDomainName];
  70         char domn[kDNSServiceMaxDomainName];
  71         char host[kDNSServiceMaxDomainName];
  72         char text[kDNSServiceMaxDomainName];
  73         InetHost      address;
  74         mDNSOpaque16  notAnIntPort;
  75         DNSServiceRef sdRef;
  76         Boolean       add;
  77         Boolean       dom;
  78         OTLink        link;
  79         } linkedServiceInfo;
  80
  81 static SearcherServices services;
  82
  83 // PrintServiceInfo prints the service information to standard out
  84 // A real application might want to do something else with the information
  85 static void PrintServiceInfo(SearcherServices *services)
  86         {
  87         OTLink *link = OTReverseList(OTLIFOStealList(&services->serviceinfolist));
  88
  89         while (link)
  90                 {
  91                 linkedServiceInfo *s = OTGetLinkObject(link, linkedServiceInfo, link);
  92
  93                 if (!services->headerPrinted)
  94                         {
  95                         printf("%-55s Type             Domain         Target Host     IP Address      Port Info\n", "Name");
  96                         services->headerPrinted = true;
  97                         }
  98
  99                 if (s->dom)
 100                         {
 101                         if (s->add) printf("%-55s available for browsing\n", s->domn);
 102                         else        printf("%-55s no longer available for browsing\n", s->domn);
 103                         }
 104                 else
 105                         {
 106                         char ip[16];
 107                         unsigned char *p = (unsigned char *)&s->address;
 108                         sprintf(ip, "%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
 109                         printf("%-55s %-16s %-14s ", s->name, s->type, s->domn);
 110                         if (s->add) printf("%-15s %-15s %5d %s\n", s->host, ip, mDNSVal16(s->notAnIntPort), s->text);
 111                         else        printf("Removed\n");
 112                         }
 113
 114                 link = link->fNext;
 115                 OTFreeMem(s);
 116                 }
 117         }
 118
 119 static void FoundInstanceAddress(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode,
 120         const char *fullname, uint16_t rrtype, uint16_t rrclass, uint16_t rdlen, const void *rdata, uint32_t ttl, void *context)
 121         {
 122         linkedServiceInfo *info = (linkedServiceInfo *)context;
 123         SearcherServices *services = info->services;
 124         (void)sdRef;                    // Unused
 125         (void)interfaceIndex;   // Unused
 126         (void)fullname;                 // Unused
 127         (void)ttl;                              // Unused
 128         if (errorCode == kDNSServiceErr_NoError)
 129                 if (flags & kDNSServiceFlagsAdd)
 130                         if (rrclass == ns_c_in && rrtype == ns_t_a && rdlen == sizeof(info->address))
 131                                 {
 132                                 memcpy(&info->address, rdata, sizeof(info->address));
 133                                 DNSServiceRefDeallocate(info->sdRef);
 134                                 OTLIFOEnqueue(&services->serviceinfolist, &info->link);
 135                                 }
 136         }
 137
 138 static void FoundInstanceInfo(DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex,
 139         DNSServiceErrorType errorCode, const char *fullname, const char *hosttarget, uint16_t notAnIntPort,
 140         uint16_t txtLen, const char *txtRecord, void *context)
 141         {
 142         linkedServiceInfo *info = (linkedServiceInfo *)context;
 143         SearcherServices *services = info->services;
 144         (void)sdRef;                    // Unused
 145         (void)flags;                    // Unused
 146         (void)interfaceIndex;   // Unused
 147         (void)errorCode;                // Unused
 148         (void)fullname;                 // Unused
 149         strcpy(info->host, hosttarget);
 150         if (txtLen == 0) info->text[0] = 0;
 151         else
 152                 {
 153                 strncpy(info->text, txtRecord+1, txtRecord[0]);
 154                 info->text[txtRecord[0]] = 0;
 155                 }
 156         info->notAnIntPort.NotAnInteger = notAnIntPort;
 157         DNSServiceRefDeallocate(info->sdRef);
 158         DNSServiceQueryRecord(&info->sdRef, 0, 0, info->host, ns_t_a, ns_c_in, FoundInstanceAddress, info);
 159         }
 160
 161 // When a new named instance of a service is found, FoundInstance() is called.
 162 // In this sample code we turn around and immediately to a DNSServiceResolve() to resolve that service name
 163 // to find its target host, port, and txtinfo, but a normal browing application would just display the name.
 164 // Resolving every single thing you find can be quite hard on the network, so you shouldn't do this
 165 // in a real application. Defer resolving until the client has picked which instance from the
 166 // long list of services is the one they want to use, and then resolve only that one.
 167 static void FoundInstance(DNSServiceRef client, DNSServiceFlags flags, uint32_t interface, DNSServiceErrorType errorCode,
 168     const char *replyName, const char *replyType, const char *replyDomain, void *context)
 169         {
 170 #pragma unused(client, interface, errorCode)
 171         SearcherServices *services = (SearcherServices *)context;
 172         linkedServiceInfo *info;
 173
 174         if (!services) { DebugStr("\pFoundInstance: services is NULL"); return; }
 175
 176         info = (linkedServiceInfo *)OTAllocMem(sizeof(linkedServiceInfo));
 177         if (!info) { services->lostRecords = true; return; }
 178
 179         info->services = services;
 180         strcpy(info->name, replyName);
 181         strcpy(info->type, replyType);
 182         strcpy(info->domn, replyDomain);
 183         info->text[0] = 0;
 184         info->add = (flags & kDNSServiceFlagsAdd) ? true : false;
 185         info->dom = false;
 186
 187         if (!info->add) // If TTL == 0 we're deleting a service,
 188                 OTLIFOEnqueue(&services->serviceinfolist, &info->link);
 189         else                                                            // else we're adding a new service
 190                 DNSServiceResolve(&info->sdRef, 0, 0, info->name, info->type, info->domn, FoundInstanceInfo, info);
 191         }
 192
 193 // YieldSomeTime() just cooperatively yields some time to other processes running on classic Mac OS
 194 static Boolean YieldSomeTime(UInt32 milliseconds)
 195         {
 196         extern Boolean SIOUXQuitting;
 197         EventRecord e;
 198         WaitNextEvent(everyEvent, &e, milliseconds / 17, NULL);
 199         SIOUXHandleOneEvent(&e);
 200         return(SIOUXQuitting);
 201         }
 202
 203 int main()
 204         {
 205         OSStatus err;
 206         void *tempmem;
 207         DNSServiceRef sdRef;
 208         DNSServiceErrorType dse;
 209
 210         SIOUXSettings.asktosaveonclose = false;
 211         SIOUXSettings.userwindowtitle  = "\pMulticast DNS Searcher";
 212         SIOUXSettings.rows             = 40;
 213         SIOUXSettings.columns          = 160;
 214
 215         printf("DNS-SD Search Client\n\n");
 216         printf("This software reports errors using MacsBug breaks,\n");
 217         printf("so if you don't have MacsBug installed your Mac may crash.\n\n");
 218         printf("******************************************************************************\n\n");
 219
 220         if (DNSServiceBrowse == (void*)kUnresolvedCFragSymbolAddress)
 221                 {
 222                 printf("Before you can use mDNS/DNS-SD clients, you need to place the \n");
 223                 printf("\"Multicast DNS & DNS-SD\" Extension in the Extensions Folder and restart\n");
 224                 return(-1);
 225                 }
 226
 227         err = InitOpenTransport();
 228         if (err) { printf("InitOpenTransport failed %d", err); return(err); }
 229
 230         // Make sure OT has a large enough memory pool for us to draw from at OTNotifier (interrupt) time
 231         tempmem = OTAllocMem(0x10000);
 232         if (tempmem) OTFreeMem(tempmem);
 233         else printf("**** Warning: OTAllocMem couldn't pre-allocate 64K for us.\n");
 234
 235         services.serviceinfolist.fHead = NULL;
 236         services.headerPrinted         = false;
 237         services.lostRecords           = false;
 238
 239         printf("Sending mDNS service lookup queries and waiting for responses...\n\n");
 240     dse = DNSServiceBrowse(&sdRef, 0, 0, "_http._tcp", "", FoundInstance, &services);
 241         if (dse == kDNSServiceErr_NoError)
 242                 {
 243                 while (!YieldSomeTime(35))
 244                         {
 245                         if (services.serviceinfolist.fHead)
 246                                 PrintServiceInfo(&services);
 247
 248                         if (services.lostRecords)
 249                                 {
 250                                 services.lostRecords = false;
 251                                 printf("**** Warning: Out of memory: Records have been missed.\n");
 252                                 }
 253                         }
 254                 }
 255
 256         DNSServiceRefDeallocate(sdRef);
 257         CloseOpenTransport();
 258         return(0);
 259         }