/* * Copyright (c) 2003-2004 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_HEADER_END@ */ #ifndef _DNS_SD_H #define _DNS_SD_H #ifdef __cplusplus extern "C" { #endif /* standard calling convention under Win32 is __stdcall */ #if defined(_WIN32) #define DNSSD_API __stdcall #else #define DNSSD_API #endif #if defined(__FreeBSD_version) && (__FreeBSD_version < 500000) /* stdint.h does not exist on FreeBSD 4.x; its types are defined in sys/types.h instead */ #include <sys/types.h> #elif defined(__sun__) #include <sys/types.h> #elif defined(_WIN32) #include <windows.h> #define _UNUSED #define bzero(a, b) memset(a, 0, b) typedef UINT8 uint8_t; typedef INT8 int8_t; typedef UINT16 uint16_t; typedef INT16 int16_t; typedef UINT32 uint32_t; typedef INT32 int32_t; #else #include <stdint.h> #endif /* DNSServiceRef, DNSRecordRef * * Opaque internal data types. * Note: client is responsible for serializing access to these structures if * they are shared between concurrent threads. */ typedef struct _DNSServiceRef_t *DNSServiceRef; typedef struct _DNSRecordRef_t *DNSRecordRef; /* General flags used in functions defined below */ enum { kDNSServiceFlagsMoreComing = 0x1, /* MoreComing indicates to a callback that at least one more result is * queued and will be delivered following immediately after this one. * Applications should not update their UI to display browse * results when the MoreComing flag is set, because this would * result in a great deal of ugly flickering on the screen. * Applications should instead wait until until MoreComing is not set, * and then update their UI. * When MoreComing is not set, that doesn't mean there will be no more * answers EVER, just that there are no more answers immediately * available right now at this instant. If more answers become available * in the future they will be delivered as usual. */ kDNSServiceFlagsAdd = 0x2, kDNSServiceFlagsDefault = 0x4, /* Flags for domain enumeration and browse/query reply callbacks. * "Default" applies only to enumeration and is only valid in * conjuction with "Add". An enumeration callback with the "Add" * flag NOT set indicates a "Remove", i.e. the domain is no longer * valid. */ kDNSServiceFlagsNoAutoRename = 0x8, /* Flag for specifying renaming behavior on name conflict when registering * non-shared records. By default, name conflicts are automatically handled * by renaming the service. NoAutoRename overrides this behavior - with this * flag set, name conflicts will result in a callback. The NoAutorename flag * is only valid if a name is explicitly specified when registering a service * (ie the default name is not used.) */ kDNSServiceFlagsShared = 0x10, kDNSServiceFlagsUnique = 0x20, /* Flag for registering individual records on a connected * DNSServiceRef. Shared indicates that there may be multiple records * with this name on the network (e.g. PTR records). Unique indicates that the * record's name is to be unique on the network (e.g. SRV records). */ kDNSServiceFlagsBrowseDomains = 0x40, kDNSServiceFlagsRegistrationDomains = 0x80, /* Flags for specifying domain enumeration type in DNSServiceEnumerateDomains. * BrowseDomains enumerates domains recommended for browsing, RegistrationDomains * enumerates domains recommended for registration. */ kDNSServiceFlagsLongLivedQuery = 0x100, /* Flag for creating a long-lived unicast query for the DNSServiceQueryRecord call. */ kDNSServiceFlagsAllowRemoteQuery = 0x200, /* Flag for creating a record for which we will answer remote queries * (queries from hosts more than one hop away; hosts not directly connected to the local link). */ kDNSServiceFlagsForceMulticast = 0x400 /* Flag for signifying that a query or registration should be performed exclusively via multicast DNS, * even for a name in a domain (e.g. foo.apple.com.) that would normally imply unicast DNS. */ }; /* * The values for DNS Classes and Types are listed in RFC 1035, and are available * on every OS in its DNS header file. Unfortunately every OS does not have the * same header file containing DNS Class and Type constants, and the names of * the constants are not consistent. For example, BIND 8 uses "T_A", * BIND 9 uses "ns_t_a", Windows uses "DNS_TYPE_A", etc. * For this reason, these constants are also listed here, so that code using * the DNS-SD programming APIs can use these constants, so that the same code * can compile on all our supported platforms. */ enum { kDNSServiceClass_IN = 1 /* Internet */ }; enum { kDNSServiceType_A = 1, /* Host address. */ kDNSServiceType_NS = 2, /* Authoritative server. */ kDNSServiceType_MD = 3, /* Mail destination. */ kDNSServiceType_MF = 4, /* Mail forwarder. */ kDNSServiceType_CNAME = 5, /* Canonical name. */ kDNSServiceType_SOA = 6, /* Start of authority zone. */ kDNSServiceType_MB = 7, /* Mailbox domain name. */ kDNSServiceType_MG = 8, /* Mail group member. */ kDNSServiceType_MR = 9, /* Mail rename name. */ kDNSServiceType_NULL = 10, /* Null resource record. */ kDNSServiceType_WKS = 11, /* Well known service. */ kDNSServiceType_PTR = 12, /* Domain name pointer. */ kDNSServiceType_HINFO = 13, /* Host information. */ kDNSServiceType_MINFO = 14, /* Mailbox information. */ kDNSServiceType_MX = 15, /* Mail routing information. */ kDNSServiceType_TXT = 16, /* Text strings. */ kDNSServiceType_RP = 17, /* Responsible person. */ kDNSServiceType_AFSDB = 18, /* AFS cell database. */ kDNSServiceType_X25 = 19, /* X_25 calling address. */ kDNSServiceType_ISDN = 20, /* ISDN calling address. */ kDNSServiceType_RT = 21, /* Router. */ kDNSServiceType_NSAP = 22, /* NSAP address. */ kDNSServiceType_NSAP_PTR = 23, /* Reverse NSAP lookup (deprecated). */ kDNSServiceType_SIG = 24, /* Security signature. */ kDNSServiceType_KEY = 25, /* Security key. */ kDNSServiceType_PX = 26, /* X.400 mail mapping. */ kDNSServiceType_GPOS = 27, /* Geographical position (withdrawn). */ kDNSServiceType_AAAA = 28, /* Ip6 Address. */ kDNSServiceType_LOC = 29, /* Location Information. */ kDNSServiceType_NXT = 30, /* Next domain (security). */ kDNSServiceType_EID = 31, /* Endpoint identifier. */ kDNSServiceType_NIMLOC = 32, /* Nimrod Locator. */ kDNSServiceType_SRV = 33, /* Server Selection. */ kDNSServiceType_ATMA = 34, /* ATM Address */ kDNSServiceType_NAPTR = 35, /* Naming Authority PoinTeR */ kDNSServiceType_KX = 36, /* Key Exchange */ kDNSServiceType_CERT = 37, /* Certification record */ kDNSServiceType_A6 = 38, /* IPv6 address (deprecates AAAA) */ kDNSServiceType_DNAME = 39, /* Non-terminal DNAME (for IPv6) */ kDNSServiceType_SINK = 40, /* Kitchen sink (experimentatl) */ kDNSServiceType_OPT = 41, /* EDNS0 option (meta-RR) */ kDNSServiceType_TKEY = 249, /* Transaction key */ kDNSServiceType_TSIG = 250, /* Transaction signature. */ kDNSServiceType_IXFR = 251, /* Incremental zone transfer. */ kDNSServiceType_AXFR = 252, /* Transfer zone of authority. */ kDNSServiceType_MAILB = 253, /* Transfer mailbox records. */ kDNSServiceType_MAILA = 254, /* Transfer mail agent records. */ kDNSServiceType_ANY = 255 /* Wildcard match. */ }; /* possible error code values */ enum { kDNSServiceErr_NoError = 0, kDNSServiceErr_Unknown = -65537, /* 0xFFFE FFFF */ kDNSServiceErr_NoSuchName = -65538, kDNSServiceErr_NoMemory = -65539, kDNSServiceErr_BadParam = -65540, kDNSServiceErr_BadReference = -65541, kDNSServiceErr_BadState = -65542, kDNSServiceErr_BadFlags = -65543, kDNSServiceErr_Unsupported = -65544, kDNSServiceErr_NotInitialized = -65545, kDNSServiceErr_AlreadyRegistered = -65547, kDNSServiceErr_NameConflict = -65548, kDNSServiceErr_Invalid = -65549, kDNSServiceErr_Firewall = -65550, kDNSServiceErr_Incompatible = -65551, /* client library incompatible with daemon */ kDNSServiceErr_BadInterfaceIndex = -65552, kDNSServiceErr_Refused = -65553, kDNSServiceErr_NoSuchRecord = -65554, kDNSServiceErr_NoAuth = -65555, kDNSServiceErr_NoSuchKey = -65556, kDNSServiceErr_NATTraversal = -65557, kDNSServiceErr_DoubleNAT = -65558, kDNSServiceErr_BadTime = -65559 /* mDNS Error codes are in the range * FFFE FF00 (-65792) to FFFE FFFF (-65537) */ }; /* Maximum length, in bytes, of a domain name represented as an escaped C-String */ /* including the final trailing dot, and the C-String terminating NULL at the end */ #define kDNSServiceMaxDomainName 1005 /* * Notes on DNS Name Escaping * -- or -- * "Why is kDNSServiceMaxDomainName 1005, when the maximum legal domain name is 255 bytes?" * * All strings used in DNS-SD are UTF-8 strings. * With few exceptions, most are also escaped using standard DNS escaping rules: * * '\\' represents a single literal '\' in the name * '\.' represents a single literal '.' in the name * '\ddd', where ddd is a three-digit decimal value from 000 to 255, * represents a single literal byte with that value. * A bare unescaped '.' is a label separator, marking a boundary between domain and subdomain. * * The exceptions, that do not use escaping, are the routines where the full * DNS name of a resource is broken, for convenience, into servicename/regtype/domain. * In these routines, the "servicename" is NOT escaped. It does not need to be, since * it is, by definition, just a single literal string. Any characters in that string * represent exactly what they are. The "regtype" portion is, technically speaking, * escaped, but since legal regtypes are only allowed to contain letters, digits, * and hyphens, the issue is moot. The "domain" portion is also escaped, though * most domains in use on the public Internet today, like regtypes, don't contain * any characters that need to be escaped. As DNS-SD becomes more popular, rich-text * domains for service discovery will become common, so software should be written * to cope with domains with escaping. * * For most software, these issues are transparent. When browsing, the discovered * servicenames should simply be displayed as-is. When resolving, the discovered * servicename/regtype/domain are simply passed unchanged to DNSServiceResolve(). * When a DNSServiceResolve() succeeds, the returned fullname is already in * the correct format to pass to standard system DNS APIs such as res_query(). * For converting from servicename/regtype/domain to a single properly-escaped * full DNS name, the helper function DNSServiceConstructFullName() is provided. * * The following (highly contrived) example illustrates the escaping process. * Suppose you have an service called "Dr. Smith\Dr. Johnson", of type "_ftp._tcp" * in subdomain "4th. Floor" of subdomain "Building 2" of domain "apple.com." * The full (escaped) DNS name of this service's SRV record would be: * Dr\.\032Smith\\Dr\.\032Johnson._ftp._tcp.4th\.\032Floor.Building\0322.apple.com. */ /* * Constants for specifying an interface index * * Specific interface indexes are identified via a 32-bit unsigned integer returned * by the if_nametoindex() family of calls. * * If the client passes 0 for interface index, that means "do the right thing", * which (at present) means, "if the name is in an mDNS local multicast domain * (e.g. 'local.', '254.169.in-addr.arpa.', '0.8.E.F.ip6.arpa.') then multicast * on all applicable interfaces, otherwise send via unicast to the appropriate * DNS server." Normally, most clients will use 0 for interface index to * automatically get the default sensible behaviour. * * If the client passes a positive interface index, then for multicast names that * indicates to do the operation only on that one interface. For unicast names the * interface index is ignored unless kDNSServiceFlagsForceMulticast is also set. * * If the client passes kDNSServiceInterfaceIndexLocalOnly when registering * a service, then that service will be found *only* by other local clients * on the same machine that are browsing using kDNSServiceInterfaceIndexLocalOnly * or kDNSServiceInterfaceIndexAny. * If a client has a 'private' service, accessible only to other processes * running on the same machine, this allows the client to advertise that service * in a way such that it does not inadvertently appear in service lists on * all the other machines on the network. * * If the client passes kDNSServiceInterfaceIndexLocalOnly when browsing * then it will find *all* records registered on that same local machine. * Clients explicitly wishing to discover *only* LocalOnly services can * accomplish this by inspecting the interfaceIndex of each service reported * to their DNSServiceBrowseReply() callback function, and discarding those * where the interface index is not kDNSServiceInterfaceIndexLocalOnly. */ #define kDNSServiceInterfaceIndexAny 0 #define kDNSServiceInterfaceIndexLocalOnly ( (uint32_t) -1 ) typedef uint32_t DNSServiceFlags; typedef int32_t DNSServiceErrorType; /********************************************************************************************* * * Unix Domain Socket access, DNSServiceRef deallocation, and data processing functions * *********************************************************************************************/ /* DNSServiceRefSockFD() * * Access underlying Unix domain socket for an initialized DNSServiceRef. * The DNS Service Discovery implmementation uses this socket to communicate between * the client and the mDNSResponder daemon. The application MUST NOT directly read from * or write to this socket. Access to the socket is provided so that it can be used as a * run loop source, or in a select() loop: when data is available for reading on the socket, * DNSServiceProcessResult() should be called, which will extract the daemon's reply from * the socket, and pass it to the appropriate application callback. By using a run loop or * select(), results from the daemon can be processed asynchronously. Without using these * constructs, DNSServiceProcessResult() will block until the response from the daemon arrives. * The client is responsible for ensuring that the data on the socket is processed in a timely * fashion - the daemon may terminate its connection with a client that does not clear its * socket buffer. * * sdRef: A DNSServiceRef initialized by any of the DNSService calls. * * return value: The DNSServiceRef's underlying socket descriptor, or -1 on * error. */ int DNSSD_API DNSServiceRefSockFD(DNSServiceRef sdRef); /* DNSServiceProcessResult() * * Read a reply from the daemon, calling the appropriate application callback. This call will * block until the daemon's response is received. Use DNSServiceRefSockFD() in * conjunction with a run loop or select() to determine the presence of a response from the * server before calling this function to process the reply without blocking. Call this function * at any point if it is acceptable to block until the daemon's response arrives. Note that the * client is responsible for ensuring that DNSServiceProcessResult() is called whenever there is * a reply from the daemon - the daemon may terminate its connection with a client that does not * process the daemon's responses. * * sdRef: A DNSServiceRef initialized by any of the DNSService calls * that take a callback parameter. * * return value: Returns kDNSServiceErr_NoError on success, otherwise returns * an error code indicating the specific failure that occurred. */ DNSServiceErrorType DNSSD_API DNSServiceProcessResult(DNSServiceRef sdRef); /* DNSServiceRefDeallocate() * * Terminate a connection with the daemon and free memory associated with the DNSServiceRef. * Any services or records registered with this DNSServiceRef will be deregistered. Any * Browse, Resolve, or Query operations called with this reference will be terminated. * * Note: If the reference's underlying socket is used in a run loop or select() call, it should * be removed BEFORE DNSServiceRefDeallocate() is called, as this function closes the reference's * socket. * * Note: If the reference was initialized with DNSServiceCreateConnection(), any DNSRecordRefs * created via this reference will be invalidated by this call - the resource records are * deregistered, and their DNSRecordRefs may not be used in subsequent functions. Similarly, * if the reference was initialized with DNSServiceRegister, and an extra resource record was * added to the service via DNSServiceAddRecord(), the DNSRecordRef created by the Add() call * is invalidated when this function is called - the DNSRecordRef may not be used in subsequent * functions. * * Note: This call is to be used only with the DNSServiceRef defined by this API. It is * not compatible with dns_service_discovery_ref objects defined in the legacy Mach-based * DNSServiceDiscovery.h API. * * sdRef: A DNSServiceRef initialized by any of the DNSService calls. * */ void DNSSD_API DNSServiceRefDeallocate(DNSServiceRef sdRef); /********************************************************************************************* * * Domain Enumeration * *********************************************************************************************/ /* DNSServiceEnumerateDomains() * * Asynchronously enumerate domains available for browsing and registration. * * The enumeration MUST be cancelled via DNSServiceRefDeallocate() when no more domains * are to be found. * * Note that the names returned are (like all of DNS-SD) UTF-8 strings, * and are escaped using standard DNS escaping rules. * (See "Notes on DNS Name Escaping" earlier in this file for more details.) * A graphical browser displaying a hierarchical tree-structured view should cut * the names at the bare dots to yield individual labels, then de-escape each * label according to the escaping rules, and then display the resulting UTF-8 text. * * DNSServiceDomainEnumReply Callback Parameters: * * sdRef: The DNSServiceRef initialized by DNSServiceEnumerateDomains(). * * flags: Possible values are: * kDNSServiceFlagsMoreComing * kDNSServiceFlagsAdd * kDNSServiceFlagsDefault * * interfaceIndex: Specifies the interface on which the domain exists. (The index for a given * interface is determined via the if_nametoindex() family of calls.) * * errorCode: Will be kDNSServiceErr_NoError (0) on success, otherwise indicates * the failure that occurred (other parameters are undefined if errorCode is nonzero). * * replyDomain: The name of the domain. * * context: The context pointer passed to DNSServiceEnumerateDomains. * */ typedef void (DNSSD_API *DNSServiceDomainEnumReply) ( DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode, const char *replyDomain, void *context ); /* DNSServiceEnumerateDomains() Parameters: * * * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, * and the enumeration operation will run indefinitely until the client * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). * * flags: Possible values are: * kDNSServiceFlagsBrowseDomains to enumerate domains recommended for browsing. * kDNSServiceFlagsRegistrationDomains to enumerate domains recommended * for registration. * * interfaceIndex: If non-zero, specifies the interface on which to look for domains. * (the index for a given interface is determined via the if_nametoindex() * family of calls.) Most applications will pass 0 to enumerate domains on * all interfaces. See "Constants for specifying an interface index" for more details. * * callBack: The function to be called when a domain is found or the call asynchronously * fails. * * context: An application context pointer which is passed to the callback function * (may be NULL). * * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous * errors are delivered to the callback), otherwise returns an error code indicating * the error that occurred (the callback is not invoked and the DNSServiceRef * is not initialized.) */ DNSServiceErrorType DNSSD_API DNSServiceEnumerateDomains ( DNSServiceRef *sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceDomainEnumReply callBack, void *context /* may be NULL */ ); /********************************************************************************************* * * Service Registration * *********************************************************************************************/ /* Register a service that is discovered via Browse() and Resolve() calls. * * * DNSServiceRegisterReply() Callback Parameters: * * sdRef: The DNSServiceRef initialized by DNSServiceRegister(). * * flags: Currently unused, reserved for future use. * * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will * indicate the failure that occurred (including name conflicts, if the * kDNSServiceFlagsNoAutoRename flag was passed to the * callout.) Other parameters are undefined if errorCode is nonzero. * * name: The service name registered (if the application did not specify a name in * DNSServiceRegister(), this indicates what name was automatically chosen). * * regtype: The type of service registered, as it was passed to the callout. * * domain: The domain on which the service was registered (if the application did not * specify a domain in DNSServiceRegister(), this indicates the default domain * on which the service was registered). * * context: The context pointer that was passed to the callout. * */ typedef void (DNSSD_API *DNSServiceRegisterReply) ( DNSServiceRef sdRef, DNSServiceFlags flags, DNSServiceErrorType errorCode, const char *name, const char *regtype, const char *domain, void *context ); /* DNSServiceRegister() Parameters: * * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, * and the registration will remain active indefinitely until the client * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). * * interfaceIndex: If non-zero, specifies the interface on which to register the service * (the index for a given interface is determined via the if_nametoindex() * family of calls.) Most applications will pass 0 to register on all * available interfaces. See "Constants for specifying an interface index" for more details. * * flags: Indicates the renaming behavior on name conflict (most applications * will pass 0). See flag definitions above for details. * * name: If non-NULL, specifies the service name to be registered. * Most applications will not specify a name, in which case the * computer name is used (this name is communicated to the client via * the callback). * * regtype: The service type followed by the protocol, separated by a dot * (e.g. "_ftp._tcp"). The transport protocol must be "_tcp" or "_udp". * New service types should be registered at htp://www.dns-sd.org/ServiceTypes.html. * * domain: If non-NULL, specifies the domain on which to advertise the service. * Most applications will not specify a domain, instead automatically * registering in the default domain(s). * * host: If non-NULL, specifies the SRV target host name. Most applications * will not specify a host, instead automatically using the machine's * default host name(s). Note that specifying a non-NULL host does NOT * create an address record for that host - the application is responsible * for ensuring that the appropriate address record exists, or creating it * via DNSServiceRegisterRecord(). * * port: The port, in network byte order, on which the service accepts connections. * Pass 0 for a "placeholder" service (i.e. a service that will not be discovered * by browsing, but will cause a name conflict if another client tries to * register that same name). Most clients will not use placeholder services. * * txtLen: The length of the txtRecord, in bytes. Must be zero if the txtRecord is NULL. * * txtRecord: The txt record rdata. May be NULL. Note that a non-NULL txtRecord * MUST be a properly formatted DNS TXT record, i.e. <length byte> <data> * <length byte> <data> ... * * callBack: The function to be called when the registration completes or asynchronously * fails. The client MAY pass NULL for the callback - The client will NOT be notified * of the default values picked on its behalf, and the client will NOT be notified of any * asynchronous errors (e.g. out of memory errors, etc.) that may prevent the registration * of the service. The client may NOT pass the NoAutoRename flag if the callback is NULL. * The client may still deregister the service at any time via DNSServiceRefDeallocate(). * * context: An application context pointer which is passed to the callback function * (may be NULL). * * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous * errors are delivered to the callback), otherwise returns an error code indicating * the error that occurred (the callback is never invoked and the DNSServiceRef * is not initialized.) * */ DNSServiceErrorType DNSSD_API DNSServiceRegister ( DNSServiceRef *sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, const char *name, /* may be NULL */ const char *regtype, const char *domain, /* may be NULL */ const char *host, /* may be NULL */ uint16_t port, uint16_t txtLen, const void *txtRecord, /* may be NULL */ DNSServiceRegisterReply callBack, /* may be NULL */ void *context /* may be NULL */ ); /* DNSServiceAddRecord() * * Add a record to a registered service. The name of the record will be the same as the * registered service's name. * The record can later be updated or deregistered by passing the RecordRef initialized * by this function to DNSServiceUpdateRecord() or DNSServiceRemoveRecord(). * * * Parameters; * * sdRef: A DNSServiceRef initialized by DNSServiceRegister(). * * RecordRef: A pointer to an uninitialized DNSRecordRef. Upon succesfull completion of this * call, this ref may be passed to DNSServiceUpdateRecord() or DNSServiceRemoveRecord(). * If the above DNSServiceRef is passed to DNSServiceRefDeallocate(), RecordRef is also * invalidated and may not be used further. * * flags: Currently ignored, reserved for future use. * * rrtype: The type of the record (e.g. kDNSServiceType_TXT, kDNSServiceType_SRV, etc) * * rdlen: The length, in bytes, of the rdata. * * rdata: The raw rdata to be contained in the added resource record. * * ttl: The time to live of the resource record, in seconds. Pass 0 to use a default value. * * return value: Returns kDNSServiceErr_NoError on success, otherwise returns an * error code indicating the error that occurred (the RecordRef is not initialized). */ DNSServiceErrorType DNSSD_API DNSServiceAddRecord ( DNSServiceRef sdRef, DNSRecordRef *RecordRef, DNSServiceFlags flags, uint16_t rrtype, uint16_t rdlen, const void *rdata, uint32_t ttl ); /* DNSServiceUpdateRecord * * Update a registered resource record. The record must either be: * - The primary txt record of a service registered via DNSServiceRegister() * - A record added to a registered service via DNSServiceAddRecord() * - An individual record registered by DNSServiceRegisterRecord() * * * Parameters: * * sdRef: A DNSServiceRef that was initialized by DNSServiceRegister() * or DNSServiceCreateConnection(). * * RecordRef: A DNSRecordRef initialized by DNSServiceAddRecord, or NULL to update the * service's primary txt record. * * flags: Currently ignored, reserved for future use. * * rdlen: The length, in bytes, of the new rdata. * * rdata: The new rdata to be contained in the updated resource record. * * ttl: The time to live of the updated resource record, in seconds. * * return value: Returns kDNSServiceErr_NoError on success, otherwise returns an * error code indicating the error that occurred. */ DNSServiceErrorType DNSSD_API DNSServiceUpdateRecord ( DNSServiceRef sdRef, DNSRecordRef RecordRef, /* may be NULL */ DNSServiceFlags flags, uint16_t rdlen, const void *rdata, uint32_t ttl ); /* DNSServiceRemoveRecord * * Remove a record previously added to a service record set via DNSServiceAddRecord(), or deregister * an record registered individually via DNSServiceRegisterRecord(). * * Parameters: * * sdRef: A DNSServiceRef initialized by DNSServiceRegister() (if the * record being removed was registered via DNSServiceAddRecord()) or by * DNSServiceCreateConnection() (if the record being removed was registered via * DNSServiceRegisterRecord()). * * recordRef: A DNSRecordRef initialized by a successful call to DNSServiceAddRecord() * or DNSServiceRegisterRecord(). * * flags: Currently ignored, reserved for future use. * * return value: Returns kDNSServiceErr_NoError on success, otherwise returns an * error code indicating the error that occurred. */ DNSServiceErrorType DNSSD_API DNSServiceRemoveRecord ( DNSServiceRef sdRef, DNSRecordRef RecordRef, DNSServiceFlags flags ); /********************************************************************************************* * * Service Discovery * *********************************************************************************************/ /* Browse for instances of a service. * * * DNSServiceBrowseReply() Parameters: * * sdRef: The DNSServiceRef initialized by DNSServiceBrowse(). * * flags: Possible values are kDNSServiceFlagsMoreComing and kDNSServiceFlagsAdd. * See flag definitions for details. * * interfaceIndex: The interface on which the service is advertised. This index should * be passed to DNSServiceResolve() when resolving the service. * * errorCode: Will be kDNSServiceErr_NoError (0) on success, otherwise will * indicate the failure that occurred. Other parameters are undefined if * the errorCode is nonzero. * * serviceName: The discovered service name. This name should be displayed to the user, * and stored for subsequent use in the DNSServiceResolve() call. * * regtype: The service type, which is usually (but not always) the same as was passed * to DNSServiceBrowse(). One case where the discovered service type may * not be the same as the requested service type is when using subtypes: * The client may want to browse for only those ftp servers that allow * anonymous connections. The client will pass the string "_ftp._tcp,_anon" * to DNSServiceBrowse(), but the type of the service that's discovered * is simply "_ftp._tcp". The regtype for each discovered service instance * should be stored along with the name, so that it can be passed to * DNSServiceResolve() when the service is later resolved. * * domain: The domain of the discovered service instance. This may or may not be the * same as the domain that was passed to DNSServiceBrowse(). The domain for each * discovered service instance should be stored along with the name, so that * it can be passed to DNSServiceResolve() when the service is later resolved. * * context: The context pointer that was passed to the callout. * */ typedef void (DNSSD_API *DNSServiceBrowseReply) ( DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode, const char *serviceName, const char *regtype, const char *replyDomain, void *context ); /* DNSServiceBrowse() Parameters: * * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, * and the browse operation will run indefinitely until the client * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). * * flags: Currently ignored, reserved for future use. * * interfaceIndex: If non-zero, specifies the interface on which to browse for services * (the index for a given interface is determined via the if_nametoindex() * family of calls.) Most applications will pass 0 to browse on all available * interfaces. See "Constants for specifying an interface index" for more details. * * regtype: The service type being browsed for followed by the protocol, separated by a * dot (e.g. "_ftp._tcp"). The transport protocol must be "_tcp" or "_udp". * * domain: If non-NULL, specifies the domain on which to browse for services. * Most applications will not specify a domain, instead browsing on the * default domain(s). * * callBack: The function to be called when an instance of the service being browsed for * is found, or if the call asynchronously fails. * * context: An application context pointer which is passed to the callback function * (may be NULL). * * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous * errors are delivered to the callback), otherwise returns an error code indicating * the error that occurred (the callback is not invoked and the DNSServiceRef * is not initialized.) */ DNSServiceErrorType DNSSD_API DNSServiceBrowse ( DNSServiceRef *sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, const char *regtype, const char *domain, /* may be NULL */ DNSServiceBrowseReply callBack, void *context /* may be NULL */ ); /* DNSServiceResolve() * * Resolve a service name discovered via DNSServiceBrowse() to a target host name, port number, and * txt record. * * Note: Applications should NOT use DNSServiceResolve() solely for txt record monitoring - use * DNSServiceQueryRecord() instead, as it is more efficient for this task. * * Note: When the desired results have been returned, the client MUST terminate the resolve by calling * DNSServiceRefDeallocate(). * * Note: DNSServiceResolve() behaves correctly for typical services that have a single SRV record and * a single TXT record (the TXT record may be empty.) To resolve non-standard services with multiple * SRV or TXT records, DNSServiceQueryRecord() should be used. * * DNSServiceResolveReply Callback Parameters: * * sdRef: The DNSServiceRef initialized by DNSServiceResolve(). * * flags: Currently unused, reserved for future use. * * interfaceIndex: The interface on which the service was resolved. * * errorCode: Will be kDNSServiceErr_NoError (0) on success, otherwise will * indicate the failure that occurred. Other parameters are undefined if * the errorCode is nonzero. * * fullname: The full service domain name, in the form <servicename>.<protocol>.<domain>. * (This name is escaped following standard DNS rules, making it suitable for * passing to standard system DNS APIs such as res_query(), or to the * special-purpose functions included in this API that take fullname parameters. * See "Notes on DNS Name Escaping" earlier in this file for more details.) * * hosttarget: The target hostname of the machine providing the service. This name can * be passed to functions like gethostbyname() to identify the host's IP address. * * port: The port, in network byte order, on which connections are accepted for this service. * * txtLen: The length of the txt record, in bytes. * * txtRecord: The service's primary txt record, in standard txt record format. * * context: The context pointer that was passed to the callout. * */ typedef void (DNSSD_API *DNSServiceResolveReply) ( DNSServiceRef sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode, const char *fullname, const char *hosttarget, uint16_t port, uint16_t txtLen, const char *txtRecord, void *context ); /* DNSServiceResolve() Parameters * * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, * and the resolve operation will run indefinitely until the client * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). * * flags: Currently ignored, reserved for future use. * * interfaceIndex: The interface on which to resolve the service. If this resolve call is * as a result of a currently active DNSServiceBrowse() operation, then the * interfaceIndex should be the index reported in the DNSServiceBrowseReply * callback. If this resolve call is using information previously saved * (e.g. in a preference file) for later use, then use interfaceIndex 0, because * the desired service may now be reachable via a different physical interface. * See "Constants for specifying an interface index" for more details. * * name: The name of the service instance to be resolved, as reported to the * DNSServiceBrowseReply() callback. * * regtype: The type of the service instance to be resolved, as reported to the * DNSServiceBrowseReply() callback. * * domain: The domain of the service instance to be resolved, as reported to the * DNSServiceBrowseReply() callback. * * callBack: The function to be called when a result is found, or if the call * asynchronously fails. * * context: An application context pointer which is passed to the callback function * (may be NULL). * * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous * errors are delivered to the callback), otherwise returns an error code indicating * the error that occurred (the callback is never invoked and the DNSServiceRef * is not initialized.) */ DNSServiceErrorType DNSSD_API DNSServiceResolve ( DNSServiceRef *sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, const char *name, const char *regtype, const char *domain, DNSServiceResolveReply callBack, void *context /* may be NULL */ ); /********************************************************************************************* * * Special Purpose Calls (most applications will not use these) * *********************************************************************************************/ /* DNSServiceCreateConnection() * * Create a connection to the daemon allowing efficient registration of * multiple individual records. * * * Parameters: * * sdRef: A pointer to an uninitialized DNSServiceRef. Deallocating * the reference (via DNSServiceRefDeallocate()) severs the * connection and deregisters all records registered on this connection. * * return value: Returns kDNSServiceErr_NoError on success, otherwise returns * an error code indicating the specific failure that occurred (in which * case the DNSServiceRef is not initialized). */ DNSServiceErrorType DNSSD_API DNSServiceCreateConnection(DNSServiceRef *sdRef); /* DNSServiceRegisterRecord * * Register an individual resource record on a connected DNSServiceRef. * * Note that name conflicts occurring for records registered via this call must be handled * by the client in the callback. * * * DNSServiceRegisterRecordReply() parameters: * * sdRef: The connected DNSServiceRef initialized by * DNSServiceDiscoveryConnect(). * * RecordRef: The DNSRecordRef initialized by DNSServiceRegisterRecord(). If the above * DNSServiceRef is passed to DNSServiceRefDeallocate(), this DNSRecordRef is * invalidated, and may not be used further. * * flags: Currently unused, reserved for future use. * * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will * indicate the failure that occurred (including name conflicts.) * Other parameters are undefined if errorCode is nonzero. * * context: The context pointer that was passed to the callout. * */ typedef void (DNSSD_API *DNSServiceRegisterRecordReply) ( DNSServiceRef sdRef, DNSRecordRef RecordRef, DNSServiceFlags flags, DNSServiceErrorType errorCode, void *context ); /* DNSServiceRegisterRecord() Parameters: * * sdRef: A DNSServiceRef initialized by DNSServiceCreateConnection(). * * RecordRef: A pointer to an uninitialized DNSRecordRef. Upon succesfull completion of this * call, this ref may be passed to DNSServiceUpdateRecord() or DNSServiceRemoveRecord(). * (To deregister ALL records registered on a single connected DNSServiceRef * and deallocate each of their corresponding DNSServiceRecordRefs, call * DNSServiceRefDealloocate()). * * flags: Possible values are kDNSServiceFlagsShared or kDNSServiceFlagsUnique * (see flag type definitions for details). * * interfaceIndex: If non-zero, specifies the interface on which to register the record * (the index for a given interface is determined via the if_nametoindex() * family of calls.) Passing 0 causes the record to be registered on all interfaces. * See "Constants for specifying an interface index" for more details. * * fullname: The full domain name of the resource record. * * rrtype: The numerical type of the resource record (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) * * rrclass: The class of the resource record (usually kDNSServiceClass_IN) * * rdlen: Length, in bytes, of the rdata. * * rdata: A pointer to the raw rdata, as it is to appear in the DNS record. * * ttl: The time to live of the resource record, in seconds. Pass 0 to use a default value. * * callBack: The function to be called when a result is found, or if the call * asynchronously fails (e.g. because of a name conflict.) * * context: An application context pointer which is passed to the callback function * (may be NULL). * * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous * errors are delivered to the callback), otherwise returns an error code indicating * the error that occurred (the callback is never invoked and the DNSRecordRef is * not initialized.) */ DNSServiceErrorType DNSSD_API DNSServiceRegisterRecord ( DNSServiceRef sdRef, DNSRecordRef *RecordRef, DNSServiceFlags flags, uint32_t interfaceIndex, const char *fullname, uint16_t rrtype, uint16_t rrclass, uint16_t rdlen, const void *rdata, uint32_t ttl, DNSServiceRegisterRecordReply callBack, void *context /* may be NULL */ ); /* DNSServiceQueryRecord * * Query for an arbitrary DNS record. * * * DNSServiceQueryRecordReply() Callback Parameters: * * sdRef: The DNSServiceRef initialized by DNSServiceQueryRecord(). * * flags: Possible values are kDNSServiceFlagsMoreComing and * kDNSServiceFlagsAdd. The Add flag is NOT set for PTR records * with a ttl of 0, i.e. "Remove" events. * * interfaceIndex: The interface on which the query was resolved (the index for a given * interface is determined via the if_nametoindex() family of calls). * See "Constants for specifying an interface index" for more details. * * errorCode: Will be kDNSServiceErr_NoError on success, otherwise will * indicate the failure that occurred. Other parameters are undefined if * errorCode is nonzero. * * fullname: The resource record's full domain name. * * rrtype: The resource record's type (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) * * rrclass: The class of the resource record (usually kDNSServiceClass_IN). * * rdlen: The length, in bytes, of the resource record rdata. * * rdata: The raw rdata of the resource record. * * ttl: The resource record's time to live, in seconds. * * context: The context pointer that was passed to the callout. * */ typedef void (DNSSD_API *DNSServiceQueryRecordReply) ( DNSServiceRef DNSServiceRef, DNSServiceFlags flags, uint32_t interfaceIndex, DNSServiceErrorType errorCode, const char *fullname, uint16_t rrtype, uint16_t rrclass, uint16_t rdlen, const void *rdata, uint32_t ttl, void *context ); /* DNSServiceQueryRecord() Parameters: * * sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds * then it initializes the DNSServiceRef, returns kDNSServiceErr_NoError, * and the query operation will run indefinitely until the client * terminates it by passing this DNSServiceRef to DNSServiceRefDeallocate(). * * flags: Pass kDNSServiceFlagsLongLivedQuery to create a "long-lived" unicast * query in a non-local domain. Without setting this flag, unicast queries * will be one-shot - that is, only answers available at the time of the call * will be returned. By setting this flag, answers (including Add and Remove * events) that become available after the initial call is made will generate * callbacks. This flag has no effect on link-local multicast queries. * * interfaceIndex: If non-zero, specifies the interface on which to issue the query * (the index for a given interface is determined via the if_nametoindex() * family of calls.) Passing 0 causes the name to be queried for on all * interfaces. See "Constants for specifying an interface index" for more details. * * fullname: The full domain name of the resource record to be queried for. * * rrtype: The numerical type of the resource record to be queried for * (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) * * rrclass: The class of the resource record (usually kDNSServiceClass_IN). * * callBack: The function to be called when a result is found, or if the call * asynchronously fails. * * context: An application context pointer which is passed to the callback function * (may be NULL). * * return value: Returns kDNSServiceErr_NoError on succeses (any subsequent, asynchronous * errors are delivered to the callback), otherwise returns an error code indicating * the error that occurred (the callback is never invoked and the DNSServiceRef * is not initialized.) */ DNSServiceErrorType DNSSD_API DNSServiceQueryRecord ( DNSServiceRef *sdRef, DNSServiceFlags flags, uint32_t interfaceIndex, const char *fullname, uint16_t rrtype, uint16_t rrclass, DNSServiceQueryRecordReply callBack, void *context /* may be NULL */ ); /* DNSServiceReconfirmRecord * * Instruct the daemon to verify the validity of a resource record that appears to * be out of date (e.g. because tcp connection to a service's target failed.) * Causes the record to be flushed from the daemon's cache (as well as all other * daemons' caches on the network) if the record is determined to be invalid. * * Parameters: * * flags: Currently unused, reserved for future use. * * interfaceIndex: If non-zero, specifies the interface of the record in question. * Passing 0 causes all instances of this record to be reconfirmed. * * fullname: The resource record's full domain name. * * rrtype: The resource record's type (e.g. kDNSServiceType_PTR, kDNSServiceType_SRV, etc) * * rrclass: The class of the resource record (usually kDNSServiceClass_IN). * * rdlen: The length, in bytes, of the resource record rdata. * * rdata: The raw rdata of the resource record. * */ void DNSSD_API DNSServiceReconfirmRecord ( DNSServiceFlags flags, uint32_t interfaceIndex, const char *fullname, uint16_t rrtype, uint16_t rrclass, uint16_t rdlen, const void *rdata ); /********************************************************************************************* * * General Utility Functions * *********************************************************************************************/ /* DNSServiceConstructFullName() * * Concatenate a three-part domain name (as returned by the above callbacks) into a * properly-escaped full domain name. Note that callbacks in the above functions ALREADY ESCAPE * strings where necessary. * * Parameters: * * fullName: A pointer to a buffer that where the resulting full domain name is to be written. * The buffer must be kDNSServiceMaxDomainName (1005) bytes in length to * accommodate the longest legal domain name without buffer overrun. * * service: The service name - any dots or slashes must NOT be escaped. * May be NULL (to construct a PTR record name, e.g. * "_ftp._tcp.apple.com"). * * regtype: The service type followed by the protocol, separated by a dot * (e.g. "_ftp._tcp"). * * domain: The domain name, e.g. "apple.com.". Literal dots or backslashes, * if any, must be escaped, e.g. "1st\. Floor.apple.com." * * return value: Returns 0 on success, -1 on error. * */ int DNSSD_API DNSServiceConstructFullName ( char *fullName, const char *service, /* may be NULL */ const char *regtype, const char *domain ); /********************************************************************************************* * * TXT Record Construction Functions * *********************************************************************************************/ /* * A typical calling sequence for TXT record construction is something like: * * Client allocates storage for TXTRecord data (e.g. declare buffer on the stack) * TXTRecordCreate(); * TXTRecordSetValue(); * TXTRecordSetValue(); * TXTRecordSetValue(); * ... * DNSServiceRegister( ... TXTRecordGetLength(), TXTRecordGetBytesPtr() ... ); * TXTRecordDeallocate(); * Explicitly deallocate storage for TXTRecord data (if not allocated on the stack) */ /* TXTRecordRef * * Opaque internal data type. * Note: Represents a DNS-SD TXT record. */ typedef struct _TXTRecordRef_t { char privatedata[16]; } TXTRecordRef; /* TXTRecordCreate() * * Creates a new empty TXTRecordRef referencing the specified storage. * * If the buffer parameter is NULL, or the specified storage size is not * large enough to hold a key subsequently added using TXTRecordSetValue(), * then additional memory will be added as needed using malloc(). * * On some platforms, when memory is low, malloc() may fail. In this * case, TXTRecordSetValue() will return kDNSServiceErr_NoMemory, and this * error condition will need to be handled as appropriate by the caller. * * You can avoid the need to handle this error condition if you ensure * that the storage you initially provide is large enough to hold all * the key/value pairs that are to be added to the record. * The caller can precompute the exact length required for all of the * key/value pairs to be added, or simply provide a fixed-sized buffer * known in advance to be large enough. * A no-value (key-only) key requires (1 + key length) bytes. * A key with empty value requires (1 + key length + 1) bytes. * A key with non-empty value requires (1 + key length + 1 + value length). * For most applications, DNS-SD TXT records are generally * less than 100 bytes, so in most cases a simple fixed-sized * 256-byte buffer will be more than sufficient. * Recommended size limits for DNS-SD TXT Records are discussed in * <http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt> * * Note: When passing parameters to and from these TXT record APIs, * the key name does not include the '=' character. The '=' character * is the separator between the key and value in the on-the-wire * packet format; it is not part of either the key or the value. * * txtRecord: A pointer to an uninitialized TXTRecordRef. * * bufferLen: The size of the storage provided in the "buffer" parameter. * * buffer: The storage used to hold the TXTRecord data. * This storage must remain valid for as long as * the TXTRecordRef. */ void DNSSD_API TXTRecordCreate ( TXTRecordRef *txtRecord, uint16_t bufferLen, void *buffer ); /* TXTRecordDeallocate() * * Releases any resources allocated in the course of preparing a TXT Record * using TXTRecordCreate()/TXTRecordSetValue()/TXTRecordRemoveValue(). * Ownership of the buffer provided in TXTRecordCreate() returns to the client. * * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). * */ void DNSSD_API TXTRecordDeallocate ( TXTRecordRef *txtRecord ); /* TXTRecordSetValue() * * Adds a key (optionally with value) to a TXTRecordRef. If the "key" already * exists in the TXTRecordRef, then the current value will be replaced with * the new value. * Keys may exist in four states with respect to a given TXT record: * - Absent (key does not appear at all) * - Present with no value ("key" appears alone) * - Present with empty value ("key=" appears in TXT record) * - Present with non-empty value ("key=value" appears in TXT record) * For more details refer to "Data Syntax for DNS-SD TXT Records" in * <http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt> * * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). * * key: A null-terminated string which only contains printable ASCII * values (0x20-0x7E), excluding '=' (0x3D). Keys should be * 8 characters or less (not counting the terminating null). * * valueSize: The size of the value. * * value: Any binary value. For values that represent * textual data, UTF-8 is STRONGLY recommended. * For values that represent textual data, valueSize * should NOT include the terminating null (if any) * at the end of the string. * If NULL, then "key" will be added with no value. * If non-NULL but valueSize is zero, then "key=" will be * added with empty value. * * return value: Returns kDNSServiceErr_NoError on success. * Returns kDNSServiceErr_Invalid if the "key" string contains * illegal characters. * Returns kDNSServiceErr_NoMemory if adding this key would * exceed the available storage. */ DNSServiceErrorType DNSSD_API TXTRecordSetValue ( TXTRecordRef *txtRecord, const char *key, uint8_t valueSize, /* may be zero */ const void *value /* may be NULL */ ); /* TXTRecordRemoveValue() * * Removes a key from a TXTRecordRef. The "key" must be an * ASCII string which exists in the TXTRecordRef. * * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). * * key: A key name which exists in the TXTRecordRef. * * return value: Returns kDNSServiceErr_NoError on success. * Returns kDNSServiceErr_NoSuchKey if the "key" does not * exist in the TXTRecordRef. * */ DNSServiceErrorType DNSSD_API TXTRecordRemoveValue ( TXTRecordRef *txtRecord, const char *key ); /* TXTRecordGetLength() * * Allows you to determine the length of the raw bytes within a TXTRecordRef. * * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). * * return value: Returns the size of the raw bytes inside a TXTRecordRef * which you can pass directly to DNSServiceRegister() or * to DNSServiceUpdateRecord(). * Returns 0 if the TXTRecordRef is empty. * */ uint16_t DNSSD_API TXTRecordGetLength ( const TXTRecordRef *txtRecord ); /* TXTRecordGetBytesPtr() * * Allows you to retrieve a pointer to the raw bytes within a TXTRecordRef. * * txtRecord: A TXTRecordRef initialized by calling TXTRecordCreate(). * * return value: Returns a pointer to the raw bytes inside the TXTRecordRef * which you can pass directly to DNSServiceRegister() or * to DNSServiceUpdateRecord(). * */ const void * DNSSD_API TXTRecordGetBytesPtr ( const TXTRecordRef *txtRecord ); /********************************************************************************************* * * TXT Record Parsing Functions * *********************************************************************************************/ /* * A typical calling sequence for TXT record parsing is something like: * * Receive TXT record data in DNSServiceResolve() callback * if (TXTRecordContainsKey(txtLen, txtRecord, "key")) then do something * val1ptr = TXTRecordGetValuePtr(txtLen, txtRecord, "key1", &len1); * val2ptr = TXTRecordGetValuePtr(txtLen, txtRecord, "key2", &len2); * ... * bcopy(val1ptr, myval1, len1); * bcopy(val2ptr, myval2, len2); * ... * return; * * If you wish to retain the values after return from the DNSServiceResolve() * callback, then you need to copy the data to your own storage using bcopy() * or similar, as shown in the example above. * * If for some reason you need to parse a TXT record you built yourself * using the TXT record construction functions above, then you can do * that using TXTRecordGetLength and TXTRecordGetBytesPtr calls: * TXTRecordGetValue(TXTRecordGetLength(x), TXTRecordGetBytesPtr(x), key, &len); * * Most applications only fetch keys they know about from a TXT record and * ignore the rest. * However, some debugging tools wish to fetch and display all keys. * To do that, use the TXTRecordGetCount() and TXTRecordGetItemAtIndex() calls. */ /* TXTRecordContainsKey() * * Allows you to determine if a given TXT Record contains a specified key. * * txtLen: The size of the received TXT Record. * * txtRecord: Pointer to the received TXT Record bytes. * * key: A null-terminated ASCII string containing the key name. * * return value: Returns 1 if the TXT Record contains the specified key. * Otherwise, it returns 0. * */ int DNSSD_API TXTRecordContainsKey ( uint16_t txtLen, const void *txtRecord, const char *key ); /* TXTRecordGetValuePtr() * * Allows you to retrieve the value for a given key from a TXT Record. * * txtLen: The size of the received TXT Record * * txtRecord: Pointer to the received TXT Record bytes. * * key: A null-terminated ASCII string containing the key name. * * valueLen: On output, will be set to the size of the "value" data. * * return value: Returns NULL if the key does not exist in this TXT record, * or exists with no value (to differentiate between * these two cases use TXTRecordContainsKey()). * Returns pointer to location within TXT Record bytes * if the key exists with empty or non-empty value. * For empty value, valueLen will be zero. * For non-empty value, valueLen will be length of value data. */ const void * DNSSD_API TXTRecordGetValuePtr ( uint16_t txtLen, const void *txtRecord, const char *key, uint8_t *valueLen ); /* TXTRecordGetCount() * * Returns the number of keys stored in the TXT Record. The count * can be used with TXTRecordGetItemAtIndex() to iterate through the keys. * * txtLen: The size of the received TXT Record. * * txtRecord: Pointer to the received TXT Record bytes. * * return value: Returns the total number of keys in the TXT Record. * */ uint16_t DNSSD_API TXTRecordGetCount ( uint16_t txtLen, const void *txtRecord ); /* TXTRecordGetItemAtIndex() * * Allows you to retrieve a key name and value pointer, given an index into * a TXT Record. Legal index values range from zero to TXTRecordGetCount()-1. * It's also possible to iterate through keys in a TXT record by simply * calling TXTRecordGetItemAtIndex() repeatedly, beginning with index zero * and increasing until TXTRecordGetItemAtIndex() returns kDNSServiceErr_Invalid. * * On return: * For keys with no value, *value is set to NULL and *valueLen is zero. * For keys with empty value, *value is non-NULL and *valueLen is zero. * For keys with non-empty value, *value is non-NULL and *valueLen is non-zero. * * txtLen: The size of the received TXT Record. * * txtRecord: Pointer to the received TXT Record bytes. * * index: An index into the TXT Record. * * keyBufLen: The size of the string buffer being supplied. * * key: A string buffer used to store the key name. * On return, the buffer contains a null-terminated C string * giving the key name. DNS-SD TXT keys are usually * 8 characters or less. To hold the maximum possible * key name, the buffer should be 256 bytes long. * * valueLen: On output, will be set to the size of the "value" data. * * value: On output, *value is set to point to location within TXT * Record bytes that holds the value data. * * return value: Returns kDNSServiceErr_NoError on success. * Returns kDNSServiceErr_NoMemory if keyBufLen is too short. * Returns kDNSServiceErr_Invalid if index is greater than * TXTRecordGetCount()-1. */ DNSServiceErrorType DNSSD_API TXTRecordGetItemAtIndex ( uint16_t txtLen, const void *txtRecord, uint16_t index, uint16_t keyBufLen, char *key, uint8_t *valueLen, const void **value ); #ifdef __APPLE_API_PRIVATE /* * Mac OS X specific functionality * 3rd party clients of this API should not depend on future support or availability of this routine */ /* DNSServiceSetDefaultDomainForUser() * * Set the default domain for the caller's UID. Future browse and registration * calls by this user that do not specify an explicit domain will browse and * register in this wide-area domain in addition to .local. In addition, this * domain will be returned as a Browse domain via domain enumeration calls. * * * Parameters: * * flags: Pass kDNSServiceFlagsAdd to add a domain for a user. Call without * this flag set to clear a previously added domain. * * domain: The domain to be used for the caller's UID. * * return value: Returns kDNSServiceErr_NoError on succeses, otherwise returns * an error code indicating the error that occurred */ DNSServiceErrorType DNSSD_API DNSServiceSetDefaultDomainForUser ( DNSServiceFlags flags, const char *domain ); #endif //__APPLE_API_PRIVATE #ifdef __cplusplus } #endif #endif /* _DNS_SD_H */