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/* -*- Mode: C; tab-width: 4 -*-
*
* Copyright (c) 2002-2003 Apple Computer, Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdio.h> // For printf()
#include <string.h> // For strlen() etc.
#include <Events.h> // For WaitNextEvent()
#include <SIOUX.h> // For SIOUXHandleOneEvent()
#include "mDNSEmbeddedAPI.h" // Defines the interface to the client layer above
#include "mDNSMacOS9.h" // Defines the specific types needed to run mDNS on this platform
// These don't have to be globals, but their memory does need to remain valid for as
// long as the search is going on. They are declared as globals here for simplicity.
static mDNS m;
static mDNS_PlatformSupport p;
static ServiceRecordSet p1, p2;
static AuthRecord availRec1, availRec2;
static Boolean availRec2Active;
// This sample code just calls mDNS_RenameAndReregisterService to automatically pick a new
// unique name for the service. For a device such as a printer, this may be appropriate.
// For a device with a user interface, and a screen, and a keyboard, the appropriate
// response may be to prompt the user and ask them to choose a new name for the service.
mDNSlocal void Callback(mDNS *const m, ServiceRecordSet *const sr, mStatus result)
{
switch (result)
{
case mStatus_NoError: debugf("Callback: %##s Name Registered", sr->RR_SRV.resrec.name.c); break;
case mStatus_NameConflict: debugf("Callback: %##s Name Conflict", sr->RR_SRV.resrec.name.c); break;
case mStatus_MemFree: debugf("Callback: %##s Memory Free", sr->RR_SRV.resrec.name.c); break;
default: debugf("Callback: %##s Unknown Result %d", sr->RR_SRV.resrec.name.c, result); break;
}
if (result == mStatus_NameConflict) mDNS_RenameAndReregisterService(m, sr, mDNSNULL);
}
// RegisterService() is a simple wrapper function which takes C string
// parameters, converts them to domainname parameters, and calls mDNS_RegisterService()
mDNSlocal void RegisterService(mDNS *m, ServiceRecordSet *recordset,
UInt16 PortAsNumber, const char txtinfo[],
const domainlabel *const n, const char type[], const char domain[])
{
domainname t;
domainname d;
char buffer[MAX_ESCAPED_DOMAIN_NAME];
UInt8 txtbuffer[512];
MakeDomainNameFromDNSNameString(&t, type);
MakeDomainNameFromDNSNameString(&d, domain);
if (txtinfo)
{
strncpy((char*)txtbuffer+1, txtinfo, sizeof(txtbuffer)-1);
txtbuffer[0] = (UInt8)strlen(txtinfo);
}
else
txtbuffer[0] = 0;
mDNS_RegisterService(m, recordset,
n, &t, &d, // Name, type, domain
mDNSNULL, mDNSOpaque16fromIntVal(PortAsNumber),
txtbuffer, (mDNSu16)(1+txtbuffer[0]), // TXT data, length
mDNSNULL, 0, // Subtypes (none)
mDNSInterface_Any, // Interface ID
Callback, mDNSNULL, 0); // Callback, context, flags
ConvertDomainNameToCString(recordset->RR_SRV.resrec.name, buffer);
printf("Made Service Records for %s\n", buffer);
}
// RegisterFakeServiceForTesting() simulates the effect of services being registered on
// dynamically-allocated port numbers. No real service exists on that port -- this is just for testing.
mDNSlocal void RegisterFakeServiceForTesting(mDNS *m, ServiceRecordSet *recordset, const char txtinfo[],
const char name[], const char type[], const char domain[])
{
static UInt16 NextPort = 0xF000;
domainlabel n;
MakeDomainLabelFromLiteralString(&n, name);
RegisterService(m, recordset, NextPort++, txtinfo, &n, type, domain);
}
// Done once on startup, and then again every time our address changes
mDNSlocal OSStatus mDNSResponderTestSetup(mDNS *m)
{
char buffer[MAX_ESCAPED_DOMAIN_NAME];
mDNSv4Addr ip = m->HostInterfaces->ip.ip.v4;
ConvertDomainNameToCString(&m->MulticastHostname, buffer);
printf("Name %s\n", buffer);
printf("IP %d.%d.%d.%d\n", ip.b[0], ip.b[1], ip.b[2], ip.b[3]);
printf("\n");
printf("Registering Service Records\n");
// Create example printer discovery records
//static ServiceRecordSet p1, p2;
RegisterFakeServiceForTesting(m, &p1, "", "One", "_raop._tcp.", "local.");
RegisterFakeServiceForTesting(m, &p2, "", "Two", "_raop._tcp.", "local.");
return(kOTNoError);
}
mDNSlocal void AvailCallback(mDNS *const m, AuthRecord *const rr, mStatus result)
{
Boolean *b = (Boolean *)rr->RecordContext;
(void)m; // Unused
// Signal that our record is now free for re-use
if (result == mStatus_MemFree) *b = false;
}
mDNSlocal OSStatus mDNSResponderSetAvail(mDNS *m, AuthRecord *rr, ServiceRecordSet *sr)
{
// 1. Initialize required fields of AuthRecord
// 2. Set name of subtype PTR record to our special subtype name denoting "available" instances
// 3. Set target of subtype PTR record to point to our SRV record (exactly the same as the main service PTR record)
// 4. And register it
mDNS_SetupResourceRecord(rr, mDNSNULL, mDNSInterface_Any, kDNSType_PTR, 2*3600, kDNSRecordTypeShared, AvailCallback, &availRec2Active);
MakeDomainNameFromDNSNameString(rr->resrec.name, "a._sub._raop._tcp.local.");
AssignDomainName(&rr->resrec.rdata->u.name, sr->RR_SRV.resrec.name);
return(mDNS_Register(m, rr));
}
// YieldSomeTime() just cooperatively yields some time to other processes running on classic Mac OS
mDNSlocal Boolean YieldSomeTime(UInt32 milliseconds)
{
extern Boolean SIOUXQuitting;
EventRecord e;
WaitNextEvent(everyEvent, &e, milliseconds / 17, NULL);
SIOUXHandleOneEvent(&e);
return(SIOUXQuitting);
}
int main()
{
mStatus err;
Boolean DoneSetup = false;
mDNSs32 nextAvail, nextBusy;
SIOUXSettings.asktosaveonclose = false;
SIOUXSettings.userwindowtitle = "\pMulticast DNS Responder";
printf("Multicast DNS Responder\n\n");
printf("This software reports errors using MacsBug breaks,\n");
printf("so if you don't have MacsBug installed your Mac may crash.\n\n");
printf("******************************************************************************\n");
err = InitOpenTransport();
if (err) { debugf("InitOpenTransport failed %d", err); return(err); }
err = mDNS_Init(&m, &p, mDNS_Init_NoCache, mDNS_Init_ZeroCacheSize,
mDNS_Init_AdvertiseLocalAddresses, mDNS_Init_NoInitCallback, mDNS_Init_NoInitCallbackContext);
if (err) return(err);
while (!YieldSomeTime(35))
{
#if MDNS_ONLYSYSTEMTASK
// For debugging, use "#define MDNS_ONLYSYSTEMTASK 1" and call mDNSPlatformIdle() periodically.
// For shipping code, don't define MDNS_ONLYSYSTEMTASK, and you don't need to call mDNSPlatformIdle()
extern void mDNSPlatformIdle(mDNS *const m);
mDNSPlatformIdle(&m); // Only needed for debugging version
#endif
if (m.mDNSPlatformStatus == mStatus_NoError && !DoneSetup)
{
DoneSetup = true;
printf("\nListening for mDNS queries...\n");
mDNSResponderTestSetup(&m);
mDNSResponderSetAvail(&m, &availRec1, &p1);
availRec2Active = false;
nextAvail = mDNS_TimeNow(&m) + mDNSPlatformOneSecond * 10;
nextBusy = mDNS_TimeNow(&m) + mDNSPlatformOneSecond * 15;
}
if (DoneSetup)
{
// We check availRec2.RecordType because we don't want to re-register this record
// if the previous mDNS_Deregister() has not yet completed
if (mDNS_TimeNow(&m) - nextAvail > 0 && !availRec2Active)
{
printf("Setting Two now available\n");
availRec2Active = true;
mDNSResponderSetAvail(&m, &availRec2, &p2);
nextAvail = nextBusy + mDNSPlatformOneSecond * 10;
}
else if (mDNS_TimeNow(&m) - nextBusy > 0)
{
printf("Setting Two now busy\n");
mDNS_Deregister(&m, &availRec2);
nextBusy = nextAvail + mDNSPlatformOneSecond * 5;
}
}
}
if (p1.RR_SRV.resrec.RecordType) mDNS_DeregisterService(&m, &p1);
if (p2.RR_SRV.resrec.RecordType) mDNS_DeregisterService(&m, &p2);
if (availRec1.resrec.RecordType) mDNS_Deregister(&m, &availRec1);
if (availRec2Active) mDNS_Deregister(&m, &availRec2);
mDNS_Close(&m);
return(0);
}
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