/* -*- Mode: C; tab-width: 4 -*-
*
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*
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* this list of conditions and the following disclaimer in the documentation
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/*! @header DNS Service Discovery
*
* @discussion This section describes the functions, callbacks, and data structures
* that make up the DNS Service Discovery API.
*
* The DNS Service Discovery API is part of Bonjour, Apple's implementation
* of zero-configuration networking (ZEROCONF).
*
* Bonjour allows you to register a network service, such as a
* printer or file server, so that it can be found by name or browsed
* for by service type and domain. Using Bonjour, applications can
* discover what services are available on the network, along with
* all the information -- such as name, IP address, and port --
* necessary to access a particular service.
*
* In effect, Bonjour combines the functions of a local DNS server and
* AppleTalk. Bonjour allows applications to provide user-friendly printer
* and server browsing, among other things, over standard IP networks.
* This behavior is a result of combining protocols such as multicast and
* DNS to add new functionality to the network (such as multicast DNS).
*
* Bonjour gives applications easy access to services over local IP
* networks without requiring the service or the application to support
* an AppleTalk or a Netbeui stack, and without requiring a DNS server
* for the local network.
*/
/* _DNS_SD_H contains the API version number for this header file
* The API version defined in this header file symbol allows for compile-time
* checking, so that C code building with earlier versions of the header file
* can avoid compile errors trying to use functions that aren't even defined
* in those earlier versions. Similar checks may also be performed at run-time:
* => weak linking -- to avoid link failures if run with an earlier
* version of the library that's missing some desired symbol, or
* => DNSServiceGetProperty(DaemonVersion) -- to verify whether the running daemon
* ("system service" on Windows) meets some required minimum functionality level.
*/
#ifndef _DNS_SD_H
#define _DNS_SD_H 8803002
#ifdef __cplusplus
extern "C" {
#endif
/* Set to 1 if libdispatch is supported
* Note: May also be set by project and/or Makefile
*/
#if defined(__APPLE__)
#define _DNS_SD_LIBDISPATCH 1
#else
#define _DNS_SD_LIBDISPATCH 0
#endif
/* standard calling convention under Win32 is __stdcall */
/* Note: When compiling Intel EFI (Extensible Firmware Interface) under MS Visual Studio, the */
/* _WIN32 symbol is defined by the compiler even though it's NOT compiling code for Windows32 */
#if defined(_WIN32) && !defined(EFI32) && !defined(EFI64)
#define DNSSD_API __stdcall
#else
#define DNSSD_API
#endif
#if (defined(__GNUC__) && (__GNUC__ >= 4))
#define DNSSD_EXPORT __attribute__((visibility("default")))
#else
#define DNSSD_EXPORT
#endif
#if defined(_WIN32)
#include <winsock2.h>
typedef SOCKET dnssd_sock_t;
#else
typedef int dnssd_sock_t;
#endif
/* stdint.h does not exist on FreeBSD 4.x; its types are defined in sys/types.h instead */
#if defined(__FreeBSD__) && (__FreeBSD__ < 5)
#include <sys/types.h>
/* Likewise, on Sun, standard integer types are in sys/types.h */
#elif defined(__sun__)
#include <sys/types.h>
/* EFI does not have stdint.h, or anything else equivalent */
#elif defined(EFI32) || defined(EFI64) || defined(EFIX64)
#include "Tiano.h"
#if !defined(_STDINT_H_)
typedef UINT8 uint8_t;
typedef INT8 int8_t;
typedef UINT16 uint16_t;
typedef INT16 int16_t;
typedef UINT32 uint32_t;
typedef INT32 int32_t;
#endif
/* Windows has its own differences */
#elif defined(_WIN32)
#include <windows.h>
#define _UNUSED
#ifndef _MSL_STDINT_H
typedef UINT8 uint8_t;
typedef INT8 int8_t;
typedef UINT16 uint16_t;
typedef INT16 int16_t;
typedef UINT32 uint32_t;
typedef INT32 int32_t;
#endif
/* All other Posix platforms use stdint.h */
#else
#include <stdint.h>
#endif
#if _DNS_SD_LIBDISPATCH
#include <dispatch/dispatch.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;
struct sockaddr;
/*! @enum General flags
* Most DNS-SD API functions and callbacks include a DNSServiceFlags parameter.
* As a general rule, any given bit in the 32-bit flags field has a specific fixed meaning,
* regardless of the function or callback being used. For any given function or callback,
* typically only a subset of the possible flags are meaningful, and all others should be zero.
* The discussion section for each API call describes which flags are valid for that call
* and callback. In some cases, for a particular call, it may be that no flags are currently
* defined, in which case the DNSServiceFlags parameter exists purely to allow future expansion.
* In all cases, developers should expect that in future releases, it is possible that new flag
* values will be defined, and write code with this in mind. For example, code that tests
* if (flags == kDNSServiceFlagsAdd) ...
* will fail if, in a future release, another bit in the 32-bit flags field is also set.
* The reliable way to test whether a particular bit is set is not with an equality test,
* but with a bitwise mask:
* if (flags & kDNSServiceFlagsAdd) ...
* With the exception of kDNSServiceFlagsValidate, each flag can be valid(be set)
* EITHER only as an input to one of the DNSService*() APIs OR only as an output
* (provide status) through any of the callbacks used. For example, kDNSServiceFlagsAdd
* can be set only as an output in the callback, whereas the kDNSServiceFlagsIncludeP2P
* can be set only as an input to the DNSService*() APIs. See comments on kDNSServiceFlagsValidate
* defined in enum 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.
* When the MoreComing flag is set, applications should not immediately
* update their UI, because this can result in a great deal of ugly flickering
* on the screen, and can waste a great deal of CPU time repeatedly updating
* the screen with content that is then immediately erased, over and over.
* Applications should wait until MoreComing is not set, and then
* update their UI when no more changes are imminent.
* 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.
*/
kDNSServiceFlagsAutoTrigger = 0x1,
/* Valid for browses using kDNSServiceInterfaceIndexAny.
* Will auto trigger the browse over AWDL as well once the service is discoveryed
* over BLE.
* This flag is an input value to DNSServiceBrowse(), which is why we can
* use the same value as kDNSServiceFlagsMoreComing, which is an output flag
* for various client callbacks.
*/
kDNSServiceFlagsAdd = 0x2,
kDNSServiceFlagsDefault = 0x4,
/* Flags for domain enumeration and browse/query reply callbacks.
* "Default" applies only to enumeration and is only valid in
* conjunction 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
* (i.e. 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.
*/
kDNSServiceFlagsForce = 0x800, // This flag is deprecated.
kDNSServiceFlagsKnownUnique = 0x800,
/*
* Client guarantees that record names are unique, so we can skip sending out initial
* probe messages. Standard name conflict resolution is still done if a conflict is discovered.
* Currently only valid for a DNSServiceRegister call.
*/
kDNSServiceFlagsReturnIntermediates = 0x1000,
/* Flag for returning intermediate results.
* For example, if a query results in an authoritative NXDomain (name does not exist)
* then that result is returned to the client. However the query is not implicitly
* cancelled -- it remains active and if the answer subsequently changes
* (e.g. because a VPN tunnel is subsequently established) then that positive
* result will still be returned to the client.
* Similarly, if a query results in a CNAME record, then in addition to following
* the CNAME referral, the intermediate CNAME result is also returned to the client.
* When this flag is not set, NXDomain errors are not returned, and CNAME records
* are followed silently without informing the client of the intermediate steps.
* (In earlier builds this flag was briefly calledkDNSServiceFlagsReturnCNAME)
*/
kDNSServiceFlagsNonBrowsable = 0x2000,
/* A service registered with the NonBrowsable flag set can be resolved using
* DNSServiceResolve(), but will not be discoverable using DNSServiceBrowse().
* This is for cases where the name is actually a GUID; it is found by other means;
* there is no end-user benefit to browsing to find a long list of opaque GUIDs.
* Using the NonBrowsable flag creates SRV+TXT without the cost of also advertising
* an associated PTR record.
*/
kDNSServiceFlagsShareConnection = 0x4000,
/* For efficiency, clients that perform many concurrent operations may want to use a
* single Unix Domain Socket connection with the background daemon, instead of having a
* separate connection for each independent operation. To use this mode, clients first
* call DNSServiceCreateConnection(&MainRef) to initialize the main DNSServiceRef.
* For each subsequent operation that is to share that same connection, the client copies
* the MainRef, and then passes the address of that copy, setting the ShareConnection flag
* to tell the library that this DNSServiceRef is not a typical uninitialized DNSServiceRef;
* it's a copy of an existing DNSServiceRef whose connection information should be reused.
*
* For example:
*
* DNSServiceErrorType error;
* DNSServiceRef MainRef;
* error = DNSServiceCreateConnection(&MainRef);
* if (error) ...
* DNSServiceRef BrowseRef = MainRef; // Important: COPY the primary DNSServiceRef first...
* error = DNSServiceBrowse(&BrowseRef, kDNSServiceFlagsShareConnection, ...); // then use the copy
* if (error) ...
* ...
* DNSServiceRefDeallocate(BrowseRef); // Terminate the browse operation
* DNSServiceRefDeallocate(MainRef); // Terminate the shared connection
* Also see Point 4.(Don't Double-Deallocate if the MainRef has been Deallocated) in Notes below:
*
* Notes:
*
* 1. Collective kDNSServiceFlagsMoreComing flag
* When callbacks are invoked using a shared DNSServiceRef, the
* kDNSServiceFlagsMoreComing flag applies collectively to *all* active
* operations sharing the same parent DNSServiceRef. If the MoreComing flag is
* set it means that there are more results queued on this parent DNSServiceRef,
* but not necessarily more results for this particular callback function.
* The implication of this for client programmers is that when a callback
* is invoked with the MoreComing flag set, the code should update its
* internal data structures with the new result, and set a variable indicating
* that its UI needs to be updated. Then, later when a callback is eventually
* invoked with the MoreComing flag not set, the code should update *all*
* stale UI elements related to that shared parent DNSServiceRef that need
* updating, not just the UI elements related to the particular callback
* that happened to be the last one to be invoked.
*
* 2. Canceling operations and kDNSServiceFlagsMoreComing
* Whenever you cancel any operation for which you had deferred UI updates
* waiting because of a kDNSServiceFlagsMoreComing flag, you should perform
* those deferred UI updates. This is because, after cancelling the operation,
* you can no longer wait for a callback *without* MoreComing set, to tell
* you do perform your deferred UI updates (the operation has been canceled,
* so there will be no more callbacks). An implication of the collective
* kDNSServiceFlagsMoreComing flag for shared connections is that this
* guideline applies more broadly -- any time you cancel an operation on
* a shared connection, you should perform all deferred UI updates for all
* operations sharing that connection. This is because the MoreComing flag
* might have been referring to events coming for the operation you canceled,
* which will now not be coming because the operation has been canceled.
*
* 3. Only share DNSServiceRef's created with DNSServiceCreateConnection
* Calling DNSServiceCreateConnection(&ref) creates a special shareable DNSServiceRef.
* DNSServiceRef's created by other calls like DNSServiceBrowse() or DNSServiceResolve()
* cannot be shared by copying them and using kDNSServiceFlagsShareConnection.
*
* 4. Don't Double-Deallocate if the MainRef has been Deallocated
* Calling DNSServiceRefDeallocate(ref) for a particular operation's DNSServiceRef terminates
* just that operation. Calling DNSServiceRefDeallocate(ref) for the main shared DNSServiceRef
* (the parent DNSServiceRef, originally created by DNSServiceCreateConnection(&ref))
* automatically terminates the shared connection and all operations that were still using it.
* After doing this, DO NOT then attempt to deallocate any remaining subordinate DNSServiceRef's.
* The memory used by those subordinate DNSServiceRef's has already been freed, so any attempt
* to do a DNSServiceRefDeallocate (or any other operation) on them will result in accesses
* to freed memory, leading to crashes or other equally undesirable results.
*
* 5. Thread Safety
* The dns_sd.h API does not presuppose any particular threading model, and consequently
* does no locking internally (which would require linking with a specific threading library).
* If the client concurrently, from multiple threads (or contexts), calls API routines using
* the same DNSServiceRef, it is the client's responsibility to provide mutual exclusion for
* that DNSServiceRef.
* For example, use of DNSServiceRefDeallocate requires caution. A common mistake is as follows:
* Thread B calls DNSServiceRefDeallocate to deallocate sdRef while Thread A is processing events
* using sdRef. Doing this will lead to intermittent crashes on thread A if the sdRef is used after
* it was deallocated.
* A telltale sign of this crash type is to see DNSServiceProcessResult on the stack preceding the
* actual crash location.
* To state this more explicitly, mDNSResponder does not queue DNSServiceRefDeallocate so
* that it occurs discretely before or after an event is handled.
*/
kDNSServiceFlagsSuppressUnusable = 0x8000,
/*
* This flag is meaningful only in DNSServiceQueryRecord which suppresses unusable queries on the
* wire. If "hostname" is a wide-area unicast DNS hostname (i.e. not a ".local." name)
* but this host has no routable IPv6 address, then the call will not try to look up IPv6 addresses
* for "hostname", since any addresses it found would be unlikely to be of any use anyway. Similarly,
* if this host has no routable IPv4 address, the call will not try to look up IPv4 addresses for
* "hostname".
*/
kDNSServiceFlagsTimeout = 0x10000,
/*
* When kDNServiceFlagsTimeout is passed to DNSServiceQueryRecord or DNSServiceGetAddrInfo, the query is
* stopped after a certain number of seconds have elapsed. The time at which the query will be stopped
* is determined by the system and cannot be configured by the user. The query will be stopped irrespective
* of whether a response was given earlier or not. When the query is stopped, the callback will be called
* with an error code of kDNSServiceErr_Timeout and a NULL sockaddr will be returned for DNSServiceGetAddrInfo
* and zero length rdata will be returned for DNSServiceQueryRecord.
*/
kDNSServiceFlagsIncludeP2P = 0x20000,
/*
* Include P2P interfaces when kDNSServiceInterfaceIndexAny is specified.
* By default, specifying kDNSServiceInterfaceIndexAny does not include P2P interfaces.
*/
kDNSServiceFlagsWakeOnResolve = 0x40000,
/*
* This flag is meaningful only in DNSServiceResolve. When set, it tries to send a magic packet
* to wake up the client.
*/
kDNSServiceFlagsBackgroundTrafficClass = 0x80000,
/*
* This flag is meaningful for Unicast DNS queries. When set, it uses the background traffic
* class for packets that service the request.
*/
kDNSServiceFlagsIncludeAWDL = 0x100000,
/*
* Include AWDL interface when kDNSServiceInterfaceIndexAny is specified.
*/
kDNSServiceFlagsValidate = 0x200000,
/*
* This flag is meaningful in DNSServiceGetAddrInfo and DNSServiceQueryRecord. This is the ONLY flag to be valid
* as an input to the APIs and also an output through the callbacks in the APIs.
*
* When this flag is passed to DNSServiceQueryRecord and DNSServiceGetAddrInfo to resolve unicast names,
* the response will be validated using DNSSEC. The validation results are delivered using the flags field in
* the callback and kDNSServiceFlagsValidate is marked in the flags to indicate that DNSSEC status is also available.
* When the callback is called to deliver the query results, the validation results may or may not be available.
* If it is not delivered along with the results, the validation status is delivered when the validation completes.
*
* When the validation results are delivered in the callback, it is indicated by marking the flags with
* kDNSServiceFlagsValidate and kDNSServiceFlagsAdd along with the DNSSEC status flags (described below) and a NULL
* sockaddr will be returned for DNSServiceGetAddrInfo and zero length rdata will be returned for DNSServiceQueryRecord.
* DNSSEC validation results are for the whole RRSet and not just individual records delivered in the callback. When
* kDNSServiceFlagsAdd is not set in the flags, applications should implicitly assume that the DNSSEC status of the
* RRSet that has been delivered up until that point is not valid anymore, till another callback is called with
* kDNSServiceFlagsAdd and kDNSServiceFlagsValidate.
*
* The following four flags indicate the status of the DNSSEC validation and marked in the flags field of the callback.
* When any of the four flags is set, kDNSServiceFlagsValidate will also be set. To check the validation status, the
* other applicable output flags should be masked. See kDNSServiceOutputFlags below.
*/
kDNSServiceFlagsSecure = 0x200010,
/*
* The response has been validated by verifying all the signatures in the response and was able to
* build a successful authentication chain starting from a known trust anchor.
*/
kDNSServiceFlagsInsecure = 0x200020,
/*
* A chain of trust cannot be built starting from a known trust anchor to the response.
*/
kDNSServiceFlagsBogus = 0x200040,
/*
* If the response cannot be verified to be secure due to expired signatures, missing signatures etc.,
* then the results are considered to be bogus.
*/
kDNSServiceFlagsIndeterminate = 0x200080,
/*
* There is no valid trust anchor that can be used to determine whether a response is secure or not.
*/
kDNSServiceFlagsUnicastResponse = 0x400000,
/*
* Request unicast response to query.
*/
kDNSServiceFlagsValidateOptional = 0x800000,
/*
* This flag is identical to kDNSServiceFlagsValidate except for the case where the response
* cannot be validated. If this flag is set in DNSServiceQueryRecord or DNSServiceGetAddrInfo,
* the DNSSEC records will be requested for validation. If they cannot be received for some reason
* during the validation (e.g., zone is not signed, zone is signed but cannot be traced back to
* root, recursive server does not understand DNSSEC etc.), then this will fallback to the default
* behavior where the validation will not be performed and no DNSSEC results will be provided.
*
* If the zone is signed and there is a valid path to a known trust anchor configured in the system
* and the application requires DNSSEC validation irrespective of the DNSSEC awareness in the current
* network, then this option MUST not be used. This is only intended to be used during the transition
* period where the different nodes participating in the DNS resolution may not understand DNSSEC or
* managed properly (e.g. missing DS record) but still want to be able to resolve DNS successfully.
*/
kDNSServiceFlagsWakeOnlyService = 0x1000000,
/*
* This flag is meaningful only in DNSServiceRegister. When set, the service will not be registered
* with sleep proxy server during sleep.
*/
kDNSServiceFlagsThresholdOne = 0x2000000,
kDNSServiceFlagsThresholdFinder = 0x4000000,
kDNSServiceFlagsThresholdReached = kDNSServiceFlagsThresholdOne,
/*
* kDNSServiceFlagsThresholdOne is meaningful only in DNSServiceBrowse. When set,
* the system will stop issuing browse queries on the network once the number
* of answers returned is one or more. It will issue queries on the network
* again if the number of answers drops to zero.
* This flag is for Apple internal use only. Third party developers
* should not rely on this behavior being supported in any given software release.
*
* kDNSServiceFlagsThresholdFinder is meaningful only in DNSServiceBrowse. When set,
* the system will stop issuing browse queries on the network once the number
* of answers has reached the threshold set for Finder.
* It will issue queries on the network again if the number of answers drops below
* this threshold.
* This flag is for Apple internal use only. Third party developers
* should not rely on this behavior being supported in any given software release.
*
* When kDNSServiceFlagsThresholdReached is set in the client callback add or remove event,
* it indicates that the browse answer threshold has been reached and no
* browse requests will be generated on the network until the number of answers falls
* below the threshold value. Add and remove events can still occur based
* on incoming Bonjour traffic observed by the system.
* The set of services return to the client is not guaranteed to represent the
* entire set of services present on the network once the threshold has been reached.
*
* Note, while kDNSServiceFlagsThresholdReached and kDNSServiceFlagsThresholdOne
* have the same value, there isn't a conflict because kDNSServiceFlagsThresholdReached
* is only set in the callbacks and kDNSServiceFlagsThresholdOne is only set on
* input to a DNSServiceBrowse call.
*/
kDNSServiceFlagsPrivateOne = 0x8000000,
/*
* This flag is private and should not be used.
*/
kDNSServiceFlagsPrivateTwo = 0x10000000,
/*
* This flag is private and should not be used.
*/
kDNSServiceFlagsPrivateThree = 0x20000000,
/*
* This flag is private and should not be used.
*/
kDNSServiceFlagsPrivateFour = 0x40000000,
/*
* This flag is private and should not be used.
*/
kDNSServiceFlagsAllowExpiredAnswers = 0x80000000,
/*
* When kDNSServiceFlagsAllowExpiredAnswers is passed to DNSServiceQueryRecord or DNSServiceGetAddrInfo,
* if there are matching expired records still in the cache, then they are immediately returned to the
* client, and in parallel a network query for that name is issued. All returned records from the query will
* remain in the cache after expiration.
*/
kDNSServiceFlagsExpiredAnswer = 0x80000000
/*
* When kDNSServiceFlagsAllowExpiredAnswers is passed to DNSServiceQueryRecord or DNSServiceGetAddrInfo,
* an expired answer will have this flag set.
*/
};
#define kDNSServiceOutputFlags (kDNSServiceFlagsValidate | kDNSServiceFlagsValidateOptional | kDNSServiceFlagsMoreComing | kDNSServiceFlagsAdd | kDNSServiceFlagsDefault)
/* All the output flags excluding the DNSSEC Status flags. Typically used to check DNSSEC Status */
/* Possible protocol values */
enum
{
/* for DNSServiceGetAddrInfo() */
kDNSServiceProtocol_IPv4 = 0x01,
kDNSServiceProtocol_IPv6 = 0x02,
/* 0x04 and 0x08 reserved for future internetwork protocols */
/* for DNSServiceNATPortMappingCreate() */
kDNSServiceProtocol_UDP = 0x10,
kDNSServiceProtocol_TCP = 0x20
/* 0x40 and 0x80 reserved for future transport protocols, e.g. SCTP [RFC 2960]
* or DCCP [RFC 4340]. If future NAT gateways are created that support port
* mappings for these protocols, new constants will be defined here.
*/
};
/*
* 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, /* One or more text strings (NOT "zero or more..."). */
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, /* IPv6 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 (deprecated) */
kDNSServiceType_DNAME = 39, /* Non-terminal DNAME (for IPv6) */
kDNSServiceType_SINK = 40, /* Kitchen sink (experimental) */
kDNSServiceType_OPT = 41, /* EDNS0 option (meta-RR) */
kDNSServiceType_APL = 42, /* Address Prefix List */
kDNSServiceType_DS = 43, /* Delegation Signer */
kDNSServiceType_SSHFP = 44, /* SSH Key Fingerprint */
kDNSServiceType_IPSECKEY = 45, /* IPSECKEY */
kDNSServiceType_RRSIG = 46, /* RRSIG */
kDNSServiceType_NSEC = 47, /* Denial of Existence */
kDNSServiceType_DNSKEY = 48, /* DNSKEY */
kDNSServiceType_DHCID = 49, /* DHCP Client Identifier */
kDNSServiceType_NSEC3 = 50, /* Hashed Authenticated Denial of Existence */
kDNSServiceType_NSEC3PARAM = 51, /* Hashed Authenticated Denial of Existence */
kDNSServiceType_HIP = 55, /* Host Identity Protocol */
kDNSServiceType_SPF = 99, /* Sender Policy Framework for E-Mail */
kDNSServiceType_UINFO = 100, /* IANA-Reserved */
kDNSServiceType_UID = 101, /* IANA-Reserved */
kDNSServiceType_GID = 102, /* IANA-Reserved */
kDNSServiceType_UNSPEC = 103, /* IANA-Reserved */
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, /* Codes up to here existed in Tiger */
kDNSServiceErr_BadSig = -65560,
kDNSServiceErr_BadKey = -65561,
kDNSServiceErr_Transient = -65562,
kDNSServiceErr_ServiceNotRunning = -65563, /* Background daemon not running */
kDNSServiceErr_NATPortMappingUnsupported = -65564, /* NAT doesn't support PCP, NAT-PMP or UPnP */
kDNSServiceErr_NATPortMappingDisabled = -65565, /* NAT supports PCP, NAT-PMP or UPnP, but it's disabled by the administrator */
kDNSServiceErr_NoRouter = -65566, /* No router currently configured (probably no network connectivity) */
kDNSServiceErr_PollingMode = -65567,
kDNSServiceErr_Timeout = -65568
/* mDNS Error codes are in the range
* FFFE FF00 (-65792) to FFFE FFFF (-65537) */
};
/* Maximum length, in bytes, of a service name represented as a */
/* literal C-String, including the terminating NULL at the end. */
#define kDNSServiceMaxServiceName 64
/* 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 1009
/*
* Notes on DNS Name Escaping
* -- or --
* "Why is kDNSServiceMaxDomainName 1009, when the maximum legal domain name is 256 bytes?"
*
* All strings used in the DNS-SD APIs are UTF-8 strings.
* Apart from the exceptions noted below, the APIs expect the strings to be properly escaped, using the
* conventional DNS escaping rules, as used by the traditional DNS res_query() API, as described below:
*
* Generally all UTF-8 characters (which includes all US ASCII characters) represent themselves,
* with two exceptions, the dot ('.') character, which is the label separator,
* and the backslash ('\') character, which is the escape character.
* The escape character ('\') is interpreted as described below:
*
* '\ddd', where ddd is a three-digit decimal value from 000 to 255,
* represents a single literal byte with that value. Any byte value may be
* represented in '\ddd' format, even characters that don't strictly need to be escaped.
* For example, the ASCII code for 'w' is 119, and therefore '\119' is equivalent to 'w'.
* Thus the command "ping '\119\119\119.apple.com'" is the equivalent to the command "ping 'www.apple.com'".
* Nonprinting ASCII characters in the range 0-31 are often represented this way.
* In particular, the ASCII NUL character (0) cannot appear in a C string because C uses it as the
* string terminator character, so ASCII NUL in a domain name has to be represented in a C string as '\000'.
* Other characters like space (ASCII code 32) are sometimes represented as '\032'
* in contexts where having an actual space character in a C string would be inconvenient.
*
* Otherwise, for all cases where a '\' is followed by anything other than a three-digit decimal value
* from 000 to 255, the character sequence '\x' represents a single literal occurrence of character 'x'.
* This is legal for any character, so, for example, '\w' is equivalent to 'w'.
* Thus the command "ping '\w\w\w.apple.com'" is the equivalent to the command "ping 'www.apple.com'".
* However, this encoding is most useful when representing the characters '.' and '\',
* which otherwise would have special meaning in DNS name strings.
* This means that the following encodings are particularly common:
* '\\' represents a single literal '\' in the name
* '\.' represents a single literal '.' in the name
*
* A lone escape character ('\') appearing at the end of a string is not allowed, since it is
* followed by neither a three-digit decimal value from 000 to 255 nor a single character.
* If a lone escape character ('\') does appear as the last character of a string, it is silently ignored.
*
* 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 US ASCII letters,
* digits, and hyphens, there is nothing to escape, so 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.
*
* The servicename may be up to 63 bytes of UTF-8 text (not counting the C-String
* terminating NULL at the end). The regtype is of the form _service._tcp or
* _service._udp, where the "service" part is 1-15 characters, which may be
* letters, digits, or hyphens. The domain part of the three-part name may be
* any legal domain, providing that the resulting servicename+regtype+domain
* name does not exceed 256 bytes.
*
* 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 a 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.', '{8,9,A,B}.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 that indicates to do the
* operation only on that one specified interface.
*
* 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 querying or
* browsing, then the LocalOnly authoritative records and /etc/hosts caches
* are searched and will find *all* records registered or configured on that
* same local machine.
*
* If interested in getting negative answers to local questions while querying
* or browsing, then set both the kDNSServiceInterfaceIndexLocalOnly and the
* kDNSServiceFlagsReturnIntermediates flags. If no local answers exist at this
* moment in time, then the reply will return an immediate negative answer. If
* local records are subsequently created that answer the question, then those
* answers will be delivered, for as long as the question is still active.
*
* If the kDNSServiceFlagsTimeout and kDNSServiceInterfaceIndexLocalOnly flags
* are set simultaneously when either DNSServiceQueryRecord or DNSServiceGetAddrInfo
* is called then both flags take effect. However, if DNSServiceQueryRecord is called
* with both the kDNSServiceFlagsSuppressUnusable and kDNSServiceInterfaceIndexLocalOnly
* flags set, then the kDNSServiceFlagsSuppressUnusable flag is ignored.
*
* Clients explicitly wishing to discover *only* LocalOnly services during a
* browse may do this, without flags, by inspecting the interfaceIndex of each
* service reported to a DNSServiceBrowseReply() callback function, and
* discarding those answers where the interface index is not set to
* kDNSServiceInterfaceIndexLocalOnly.
*
* kDNSServiceInterfaceIndexP2P is meaningful only in Browse, QueryRecord, Register,
* and Resolve operations. It should not be used in other DNSService APIs.
*
* - If kDNSServiceInterfaceIndexP2P is passed to DNSServiceBrowse or
* DNSServiceQueryRecord, it restricts the operation to P2P.
*
* - If kDNSServiceInterfaceIndexP2P is passed to DNSServiceRegister, it is
* mapped internally to kDNSServiceInterfaceIndexAny with the kDNSServiceFlagsIncludeP2P
* set.
*
* - If kDNSServiceInterfaceIndexP2P is passed to DNSServiceResolve, it is
* mapped internally to kDNSServiceInterfaceIndexAny with the kDNSServiceFlagsIncludeP2P
* set, because resolving a P2P service may create and/or enable an interface whose
* index is not known a priori. The resolve callback will indicate the index of the
* interface via which the service can be accessed.
*
* If applications pass kDNSServiceInterfaceIndexAny to DNSServiceBrowse
* or DNSServiceQueryRecord, they must set the kDNSServiceFlagsIncludeP2P flag
* to include P2P. In this case, if a service instance or the record being queried
* is found over P2P, the resulting ADD event will indicate kDNSServiceInterfaceIndexP2P
* as the interface index.
*/
#define kDNSServiceInterfaceIndexAny 0
#define kDNSServiceInterfaceIndexLocalOnly ((uint32_t)-1)
#define kDNSServiceInterfaceIndexUnicast ((uint32_t)-2)
#define kDNSServiceInterfaceIndexP2P ((uint32_t)-3)
#define kDNSServiceInterfaceIndexBLE ((uint32_t)-4)
typedef uint32_t DNSServiceFlags;
typedef uint32_t DNSServiceProtocol;
typedef int32_t DNSServiceErrorType;
/*********************************************************************************************
*
* Version checking
*
*********************************************************************************************/
/* DNSServiceGetProperty() Parameters:
*
* property: The requested property.
* Currently the only property defined is kDNSServiceProperty_DaemonVersion.
*
* result: Place to store result.
* For retrieving DaemonVersion, this should be the address of a uint32_t.
*
* size: Pointer to uint32_t containing size of the result location.
* For retrieving DaemonVersion, this should be sizeof(uint32_t).
* On return the uint32_t is updated to the size of the data returned.
* For DaemonVersion, the returned size is always sizeof(uint32_t), but
* future properties could be defined which return variable-sized results.
*
* return value: Returns kDNSServiceErr_NoError on success, or kDNSServiceErr_ServiceNotRunning
* if the daemon (or "system service" on Windows) is not running.
*/
DNSSD_EXPORT
DNSServiceErrorType DNSSD_API DNSServiceGetProperty
(
const char *property, /* Requested property (i.e. kDNSServiceProperty_DaemonVersion) */
void *result, /* Pointer to place to store result */
uint32_t *size /* size of result location */
);
/*
* When requesting kDNSServiceProperty_DaemonVersion, the result pointer must point
* to a 32-bit unsigned integer, and the size parameter must be set to sizeof(uint32_t).
*
* On return, the 32-bit unsigned integer contains the API version number
*
* For example, Mac OS X 10.4.9 has API version 1080400.
* This allows applications to do simple greater-than and less-than comparisons:
* e.g. an application that requires at least API version 1080400 can check:
* if (version >= 1080400) ...
*
* Example usage:
* uint32_t version;
* uint32_t size = sizeof(version);
* DNSServiceErrorType err = DNSServiceGetProperty(kDNSServiceProperty_DaemonVersion, &version, &size);
* if (!err) printf("DNS_SD API version is %d.%d\n", version / 10000, version / 100 % 100);
*/
#define kDNSServiceProperty_DaemonVersion "DaemonVersion"
/*********************************************************************************************
*
* Unix Domain Socket access, DNSServiceRef deallocation, and data processing functions
*
*********************************************************************************************/
/* DNSServiceRefSockFD()
*
* Access underlying Unix domain socket for an initialized DNSServiceRef.
* The DNS Service Discovery implementation uses this socket to communicate between the client and
* the 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 kqueue event source, a CFRunLoop
* event source, in a select() loop, etc. When the underlying event management subsystem (kqueue/
* select/CFRunLoop etc.) indicates to the client that data is available for reading on the
* socket, the client should call DNSServiceProcessResult(), 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. Alternatively,
* a client can choose to fork a thread and have it loop calling "DNSServiceProcessResult(ref);"
* If DNSServiceProcessResult() is called when no data is available for reading on the socket, it
* will block until data does become available, and then process the data and return to the caller.
* The application is responsible for checking the return value of DNSServiceProcessResult()
* to determine if the socket is valid and if it should continue to process data on the socket.
* When data arrives on the socket, the client is responsible for calling DNSServiceProcessResult(ref)
* in a timely fashion -- if the client allows a large backlog of data to build up the daemon
* may terminate the connection.
*
* sdRef: A DNSServiceRef initialized by any of the DNSService calls.
*
* return value: The DNSServiceRef's underlying socket descriptor, or -1 on
* error.
*/
DNSSD_EXPORT
dnssd_sock_t 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.
*/
DNSSD_EXPORT
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.
*
* sdRef: A DNSServiceRef initialized by any of the DNSService calls.
*
*/
DNSSD_EXPORT
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 success (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).
*/
DNSSD_EXPORT
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: When a name is successfully registered, the callback will be
* invoked with the kDNSServiceFlagsAdd flag set. When Wide-Area
* DNS-SD is in use, it is possible for a single service to get
* more than one success callback (e.g. one in the "local" multicast
* DNS domain, and another in a wide-area unicast DNS domain).
* If a successfully-registered name later suffers a name conflict
* or similar problem and has to be deregistered, the callback will
* be invoked with the kDNSServiceFlagsAdd flag not set. The callback
* is *not* invoked in the case where the caller explicitly terminates
* the service registration by calling DNSServiceRefDeallocate(ref);
*
* errorCode: Will be kDNSServiceErr_NoError on success, otherwise will
* indicate the failure that occurred (including name conflicts,
* if the kDNSServiceFlagsNoAutoRename flag was used when registering.)
* 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().
*
* flags: Indicates the renaming behavior on name conflict (most applications
* will pass 0). See flag definitions above for details.
*
* 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.
*
* 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).
* If a name is specified, it must be 1-63 bytes of UTF-8 text.
* If the name is longer than 63 bytes it will be automatically truncated
* to a legal length, unless the NoAutoRename flag is set,
* in which case kDNSServiceErr_BadParam will be returned.
*
* regtype: The service type followed by the protocol, separated by a dot
* (e.g. "_ftp._tcp"). The service type must be an underscore, followed
* by 1-15 characters, which may be letters, digits, or hyphens.
* The transport protocol must be "_tcp" or "_udp". New service types
* should be registered at <http://www.dns-sd.org/ServiceTypes.html>.
*
* Additional subtypes of the primary service type (where a service
* type has defined subtypes) follow the primary service type in a
* comma-separated list, with no additional spaces, e.g.
* "_primarytype._tcp,_subtype1,_subtype2,_subtype3"
* Subtypes provide a mechanism for filtered browsing: A client browsing
* for "_primarytype._tcp" will discover all instances of this type;
* a client browsing for "_primarytype._tcp,_subtype2" will discover only
* those instances that were registered with "_subtype2" in their list of
* registered subtypes.
*
* The subtype mechanism can be illustrated with some examples using the
* dns-sd command-line tool:
*
* % dns-sd -R Simple _test._tcp "" 1001 &
* % dns-sd -R Better _test._tcp,HasFeatureA "" 1002 &
* % dns-sd -R Best _test._tcp,HasFeatureA,HasFeatureB "" 1003 &
*
* Now:
* % dns-sd -B _test._tcp # will find all three services
* % dns-sd -B _test._tcp,HasFeatureA # finds "Better" and "Best"
* % dns-sd -B _test._tcp,HasFeatureB # finds only "Best"
*
* Subtype labels may be up to 63 bytes long, and may contain any eight-
* bit byte values, including zero bytes. However, due to the nature of
* using a C-string-based API, conventional DNS escaping must be used for
* dots ('.'), commas (','), backslashes ('\') and zero bytes, as shown below:
*
* % dns-sd -R Test '_test._tcp,s\.one,s\,two,s\\three,s\000four' local 123
*
* When a service is registered, all the clients browsing for the registered
* type ("regtype") will discover it. If the discovery should be
* restricted to a smaller set of well known peers, the service can be
* registered with additional data (group identifier) that is known
* only to a smaller set of peers. The group identifier should follow primary
* service type using a colon (":") as a delimeter. If subtypes are also present,
* it should be given before the subtype as shown below.
*
* % dns-sd -R _test1 _http._tcp:mygroup1 local 1001
* % dns-sd -R _test2 _http._tcp:mygroup2 local 1001
* % dns-sd -R _test3 _http._tcp:mygroup3,HasFeatureA local 1001
*
* Now:
* % dns-sd -B _http._tcp:"mygroup1" # will discover only test1
* % dns-sd -B _http._tcp:"mygroup2" # will discover only test2
* % dns-sd -B _http._tcp:"mygroup3",HasFeatureA # will discover only test3
*
* By specifying the group information, only the members of that group are
* discovered.
*
* The group identifier itself is not sent in clear. Only a hash of the group
* identifier is sent and the clients discover them anonymously. The group identifier
* may be up to 256 bytes long and may contain any eight bit values except comma which
* should be escaped.
*
* 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. A non-NULL txtRecord MUST be a properly formatted DNS
* TXT record, i.e. <length byte> <data> <length byte> <data> ...
* Passing NULL for the txtRecord is allowed as a synonym for txtLen=1, txtRecord="",
* i.e. it creates a TXT record of length one containing a single empty string.
* RFC 1035 doesn't allow a TXT record to contain *zero* strings, so a single empty
* string is the smallest legal DNS TXT record.
* As with the other parameters, the DNSServiceRegister call copies the txtRecord
* data; e.g. if you allocated the storage for the txtRecord parameter with malloc()
* then you can safely free that memory right after the DNSServiceRegister call returns.
*
* 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 success (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).
*/
DNSSD_EXPORT
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, /* In network byte order */
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().
*
* Note that the DNSServiceAddRecord/UpdateRecord/RemoveRecord are *NOT* thread-safe
* with respect to a single DNSServiceRef. If you plan to have multiple threads
* in your program simultaneously add, update, or remove records from the same
* DNSServiceRef, then it's the caller's responsibility to use a mutex lock
* or take similar appropriate precautions to serialize those calls.
*
* 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.
* Most clients should pass 0 to indicate that the system should
* select a sensible default value.
*
* return value: Returns kDNSServiceErr_NoError on success, otherwise returns an
* error code indicating the error that occurred (the RecordRef is not initialized).
*/
DNSSD_EXPORT
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.
* Most clients should pass 0 to indicate that the system should
* select a sensible default value.
*
* return value: Returns kDNSServiceErr_NoError on success, otherwise returns an
* error code indicating the error that occurred.
*/
DNSSD_EXPORT
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
* a 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.
*/
DNSSD_EXPORT
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".
* A client may optionally specify a single subtype to perform filtered browsing:
* e.g. browsing for "_primarytype._tcp,_subtype" will discover only those
* instances of "_primarytype._tcp" that were registered specifying "_subtype"
* in their list of registered subtypes. Additionally, a group identifier may
* also be specified before the subtype e.g., _primarytype._tcp:GroupID, which
* will discover only the members that register the service with GroupID. See
* DNSServiceRegister for more details.
*
* 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 success (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).
*/
DNSSD_EXPORT
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. 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: Possible values: kDNSServiceFlagsMoreComing
*
* 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.
*
* NOTE: In earlier versions of this header file, the txtRecord parameter was declared "const char *"
* This is incorrect, since it contains length bytes which are values in the range 0 to 255, not -128 to +127.
* Depending on your compiler settings, this change may cause signed/unsigned mismatch warnings.
* These should be fixed by updating your own callback function definition to match the corrected
* function signature using "const unsigned char *txtRecord". Making this change may also fix inadvertent
* bugs in your callback function, where it could have incorrectly interpreted a length byte with value 250
* as being -6 instead, with various bad consequences ranging from incorrect operation to software crashes.
* If you need to maintain portable code that will compile cleanly with both the old and new versions of
* this header file, you should update your callback function definition to use the correct unsigned value,
* and then in the place where you pass your callback function to DNSServiceResolve(), use a cast to eliminate
* the compiler warning, e.g.:
* DNSServiceResolve(sd, flags, index, name, regtype, domain, (DNSServiceResolveReply)MyCallback, context);
* This will ensure that your code compiles cleanly without warnings (and more importantly, works correctly)
* with both the old header and with the new corrected version.
*
*/
typedef void (DNSSD_API *DNSServiceResolveReply)
(
DNSServiceRef sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
DNSServiceErrorType errorCode,
const char *fullname,
const char *hosttarget,
uint16_t port, /* In network byte order */
uint16_t txtLen,
const unsigned 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: Specifying kDNSServiceFlagsForceMulticast will cause query to be
* performed with a link-local mDNS query, even if the name is an
* apparently non-local name (i.e. a name not ending in ".local.")
*
* 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 success (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).
*/
DNSSD_EXPORT
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 */
);
/*********************************************************************************************
*
* Querying Individual Specific Records
*
*********************************************************************************************/
/* 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: If the client wishes to cache the result for performance reasons,
* the TTL indicates how long the client may legitimately hold onto
* this result, in seconds. After the TTL expires, the client should
* consider the result no longer valid, and if it requires this data
* again, it should be re-fetched with a new query. Of course, this
* only applies to clients that cancel the asynchronous operation when
* they get a result. Clients that leave the asynchronous operation
* running can safely assume that the data remains valid until they
* get another callback telling them otherwise. The ttl value is not
* updated when the daemon answers from the cache, hence relying on
* the accuracy of the ttl value is not recommended.
*
* context: The context pointer that was passed to the callout.
*
*/
typedef void (DNSSD_API *DNSServiceQueryRecordReply)
(
DNSServiceRef sdRef,
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: kDNSServiceFlagsForceMulticast or kDNSServiceFlagsLongLivedQuery.
* Pass kDNSServiceFlagsLongLivedQuery to create a "long-lived" unicast
* query to a unicast DNS server that implements the protocol. 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 success (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).
*/
DNSSD_EXPORT
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 */
);
/*********************************************************************************************
*
* Unified lookup of both IPv4 and IPv6 addresses for a fully qualified hostname
*
*********************************************************************************************/
/* DNSServiceGetAddrInfo
*
* Queries for the IP address of a hostname by using either Multicast or Unicast DNS.
*
* DNSServiceGetAddrInfoReply() parameters:
*
* sdRef: The DNSServiceRef initialized by DNSServiceGetAddrInfo().
*
* flags: Possible values are kDNSServiceFlagsMoreComing and
* kDNSServiceFlagsAdd.
*
* interfaceIndex: The interface to which the answers pertain.
*
* errorCode: Will be kDNSServiceErr_NoError on success, otherwise will
* indicate the failure that occurred. Other parameters are
* undefined if errorCode is nonzero.
*
* hostname: The fully qualified domain name of the host to be queried for.
*
* address: IPv4 or IPv6 address.
*
* ttl: If the client wishes to cache the result for performance reasons,
* the TTL indicates how long the client may legitimately hold onto
* this result, in seconds. After the TTL expires, the client should
* consider the result no longer valid, and if it requires this data
* again, it should be re-fetched with a new query. Of course, this
* only applies to clients that cancel the asynchronous operation when
* they get a result. Clients that leave the asynchronous operation
* running can safely assume that the data remains valid until they
* get another callback telling them otherwise. The ttl value is not
* updated when the daemon answers from the cache, hence relying on
* the accuracy of the ttl value is not recommended.
*
* context: The context pointer that was passed to the callout.
*
*/
typedef void (DNSSD_API *DNSServiceGetAddrInfoReply)
(
DNSServiceRef sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
DNSServiceErrorType errorCode,
const char *hostname,
const struct sockaddr *address,
uint32_t ttl,
void *context
);
/* DNSServiceGetAddrInfo() Parameters:
*
* sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds then it
* initializes the DNSServiceRef, returns kDNSServiceErr_NoError, and the query
* begins and will last indefinitely until the client terminates the query
* by passing this DNSServiceRef to DNSServiceRefDeallocate().
*
* flags: kDNSServiceFlagsForceMulticast
*
* interfaceIndex: The interface on which to issue the query. Passing 0 causes the query to be
* sent on all active interfaces via Multicast or the primary interface via Unicast.
*
* protocol: Pass in kDNSServiceProtocol_IPv4 to look up IPv4 addresses, or kDNSServiceProtocol_IPv6
* to look up IPv6 addresses, or both to look up both kinds. If neither flag is
* set, the system will apply an intelligent heuristic, which is (currently)
* that it will attempt to look up both, except:
*
* * If "hostname" is a wide-area unicast DNS hostname (i.e. not a ".local." name)
* but this host has no routable IPv6 address, then the call will not try to
* look up IPv6 addresses for "hostname", since any addresses it found would be
* unlikely to be of any use anyway. Similarly, if this host has no routable
* IPv4 address, the call will not try to look up IPv4 addresses for "hostname".
*
* hostname: The fully qualified domain name of the host to be queried for.
*
* callBack: The function to be called when the query succeeds or fails asynchronously.
*
* context: An application context pointer which is passed to the callback function
* (may be NULL).
*
* return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
* errors are delivered to the callback), otherwise returns an error code indicating
* the error that occurred.
*/
DNSSD_EXPORT
DNSServiceErrorType DNSSD_API DNSServiceGetAddrInfo
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
DNSServiceProtocol protocol,
const char *hostname,
DNSServiceGetAddrInfoReply callBack,
void *context /* may be NULL */
);
/*********************************************************************************************
*
* Special Purpose Calls:
* DNSServiceCreateConnection(), DNSServiceRegisterRecord(), DNSServiceReconfirmRecord()
* (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).
*/
DNSSD_EXPORT
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
* DNSServiceCreateConnection().
*
* 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
* DNSServiceRefDeallocate()).
*
* 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.
* Most clients should pass 0 to indicate that the system should
* select a sensible 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 success (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).
*/
DNSSD_EXPORT
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 */
);
/* 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.
* Use this routine conservatively. Reconfirming a record necessarily consumes
* network bandwidth, so this should not be done indiscriminately.
*
* Parameters:
*
* flags: Not currently used.
*
* interfaceIndex: Specifies the interface of the record in question.
* The caller must specify the interface.
* This API (by design) causes increased network traffic, so it requires
* the caller to be precise about which record should be reconfirmed.
* It is not possible to pass zero for the interface index to perform
* a "wildcard" reconfirmation, where *all* matching records are 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.
*
*/
DNSSD_EXPORT
DNSServiceErrorType DNSSD_API DNSServiceReconfirmRecord
(
DNSServiceFlags flags,
uint32_t interfaceIndex,
const char *fullname,
uint16_t rrtype,
uint16_t rrclass,
uint16_t rdlen,
const void *rdata
);
/*********************************************************************************************
*
* NAT Port Mapping
*
*********************************************************************************************/
/* DNSServiceNATPortMappingCreate
*
* Request a port mapping in the NAT gateway, which maps a port on the local machine
* to an external port on the NAT. The NAT should support either PCP, NAT-PMP or the
* UPnP/IGD protocol for this API to create a successful mapping. Note that this API
* currently supports IPv4 addresses/mappings only. If the NAT gateway supports PCP and
* returns an IPv6 address (incorrectly, since this API specifically requests IPv4
* addresses), the DNSServiceNATPortMappingReply callback will be invoked with errorCode
* kDNSServiceErr_NATPortMappingUnsupported.
*
* The port mapping will be renewed indefinitely until the client process exits, or
* explicitly terminates the port mapping request by calling DNSServiceRefDeallocate().
* The client callback will be invoked, informing the client of the NAT gateway's
* external IP address and the external port that has been allocated for this client.
* The client should then record this external IP address and port using whatever
* directory service mechanism it is using to enable peers to connect to it.
* (Clients advertising services using Wide-Area DNS-SD DO NOT need to use this API
* -- when a client calls DNSServiceRegister() NAT mappings are automatically created
* and the external IP address and port for the service are recorded in the global DNS.
* Only clients using some directory mechanism other than Wide-Area DNS-SD need to use
* this API to explicitly map their own ports.)
*
* It's possible that the client callback could be called multiple times, for example
* if the NAT gateway's IP address changes, or if a configuration change results in a
* different external port being mapped for this client. Over the lifetime of any long-lived
* port mapping, the client should be prepared to handle these notifications of changes
* in the environment, and should update its recorded address and/or port as appropriate.
*
* NOTE: There are two unusual aspects of how the DNSServiceNATPortMappingCreate API works,
* which were intentionally designed to help simplify client code:
*
* 1. It's not an error to request a NAT mapping when the machine is not behind a NAT gateway.
* In other NAT mapping APIs, if you request a NAT mapping and the machine is not behind a NAT
* gateway, then the API returns an error code -- it can't get you a NAT mapping if there's no
* NAT gateway. The DNSServiceNATPortMappingCreate API takes a different view. Working out
* whether or not you need a NAT mapping can be tricky and non-obvious, particularly on
* a machine with multiple active network interfaces. Rather than make every client recreate
* this logic for deciding whether a NAT mapping is required, the PortMapping API does that
* work for you. If the client calls the PortMapping API when the machine already has a
* routable public IP address, then instead of complaining about it and giving an error,
* the PortMapping API just invokes your callback, giving the machine's public address
* and your own port number. This means you don't need to write code to work out whether
* your client needs to call the PortMapping API -- just call it anyway, and if it wasn't
* necessary, no harm is done:
*
* - If the machine already has a routable public IP address, then your callback
* will just be invoked giving your own address and port.
* - If a NAT mapping is required and obtained, then your callback will be invoked
* giving you the external address and port.
* - If a NAT mapping is required but not obtained from the local NAT gateway,
* or the machine has no network connectivity, then your callback will be
* invoked giving zero address and port.
*
* 2. In other NAT mapping APIs, if a laptop computer is put to sleep and woken up on a new
* network, it's the client's job to notice this, and work out whether a NAT mapping
* is required on the new network, and make a new NAT mapping request if necessary.
* The DNSServiceNATPortMappingCreate API does this for you, automatically.
* The client just needs to make one call to the PortMapping API, and its callback will
* be invoked any time the mapping state changes. This property complements point (1) above.
* If the client didn't make a NAT mapping request just because it determined that one was
* not required at that particular moment in time, the client would then have to monitor
* for network state changes to determine if a NAT port mapping later became necessary.
* By unconditionally making a NAT mapping request, even when a NAT mapping not to be
* necessary, the PortMapping API will then begin monitoring network state changes on behalf of
* the client, and if a NAT mapping later becomes necessary, it will automatically create a NAT
* mapping and inform the client with a new callback giving the new address and port information.
*
* DNSServiceNATPortMappingReply() parameters:
*
* sdRef: The DNSServiceRef initialized by DNSServiceNATPortMappingCreate().
*
* flags: Currently unused, reserved for future use.
*
* interfaceIndex: The interface through which the NAT gateway is reached.
*
* errorCode: Will be kDNSServiceErr_NoError on success.
* Will be kDNSServiceErr_DoubleNAT when the NAT gateway is itself behind one or
* more layers of NAT, in which case the other parameters have the defined values.
* For other failures, will indicate the failure that occurred, and the other
* parameters are undefined.
*
* externalAddress: Four byte IPv4 address in network byte order.
*
* protocol: Will be kDNSServiceProtocol_UDP or kDNSServiceProtocol_TCP or both.
*
* internalPort: The port on the local machine that was mapped.
*
* externalPort: The actual external port in the NAT gateway that was mapped.
* This is likely to be different than the requested external port.
*
* ttl: The lifetime of the NAT port mapping created on the gateway.
* This controls how quickly stale mappings will be garbage-collected
* if the client machine crashes, suffers a power failure, is disconnected
* from the network, or suffers some other unfortunate demise which
* causes it to vanish without explicitly removing its NAT port mapping.
* It's possible that the ttl value will differ from the requested ttl value.
*
* context: The context pointer that was passed to the callout.
*
*/
typedef void (DNSSD_API *DNSServiceNATPortMappingReply)
(
DNSServiceRef sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
DNSServiceErrorType errorCode,
uint32_t externalAddress, /* four byte IPv4 address in network byte order */
DNSServiceProtocol protocol,
uint16_t internalPort, /* In network byte order */
uint16_t externalPort, /* In network byte order and may be different than the requested port */
uint32_t ttl, /* may be different than the requested ttl */
void *context
);
/* DNSServiceNATPortMappingCreate() Parameters:
*
* sdRef: A pointer to an uninitialized DNSServiceRef. If the call succeeds then it
* initializes the DNSServiceRef, returns kDNSServiceErr_NoError, and the nat
* port mapping will last indefinitely until the client terminates the port
* mapping request by passing this DNSServiceRef to DNSServiceRefDeallocate().
*
* flags: Currently ignored, reserved for future use.
*
* interfaceIndex: The interface on which to create port mappings in a NAT gateway. Passing 0 causes
* the port mapping request to be sent on the primary interface.
*
* protocol: To request a port mapping, pass in kDNSServiceProtocol_UDP, or kDNSServiceProtocol_TCP,
* or (kDNSServiceProtocol_UDP | kDNSServiceProtocol_TCP) to map both.
* The local listening port number must also be specified in the internalPort parameter.
* To just discover the NAT gateway's external IP address, pass zero for protocol,
* internalPort, externalPort and ttl.
*
* internalPort: The port number in network byte order on the local machine which is listening for packets.
*
* externalPort: The requested external port in network byte order in the NAT gateway that you would
* like to map to the internal port. Pass 0 if you don't care which external port is chosen for you.
*
* ttl: The requested renewal period of the NAT port mapping, in seconds.
* If the client machine crashes, suffers a power failure, is disconnected from
* the network, or suffers some other unfortunate demise which causes it to vanish
* unexpectedly without explicitly removing its NAT port mappings, then the NAT gateway
* will garbage-collect old stale NAT port mappings when their lifetime expires.
* Requesting a short TTL causes such orphaned mappings to be garbage-collected
* more promptly, but consumes system resources and network bandwidth with
* frequent renewal packets to keep the mapping from expiring.
* Requesting a long TTL is more efficient on the network, but in the event of the
* client vanishing, stale NAT port mappings will not be garbage-collected as quickly.
* Most clients should pass 0 to use a system-wide default value.
*
* callBack: The function to be called when the port mapping request succeeds or fails asynchronously.
*
* context: An application context pointer which is passed to the callback function
* (may be NULL).
*
* return value: Returns kDNSServiceErr_NoError on success (any subsequent, asynchronous
* errors are delivered to the callback), otherwise returns an error code indicating
* the error that occurred.
*
* If you don't actually want a port mapped, and are just calling the API
* because you want to find out the NAT's external IP address (e.g. for UI
* display) then pass zero for protocol, internalPort, externalPort and ttl.
*/
DNSSD_EXPORT
DNSServiceErrorType DNSSD_API DNSServiceNATPortMappingCreate
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
DNSServiceProtocol protocol, /* TCP and/or UDP */
uint16_t internalPort, /* network byte order */
uint16_t externalPort, /* network byte order */
uint32_t ttl, /* time to live in seconds */
DNSServiceNATPortMappingReply callBack,
void *context /* may be NULL */
);
/*********************************************************************************************
*
* 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 (1009) bytes in length to
* accommodate the longest legal domain name without buffer overrun.
*
* service: The service name - any dots or backslashes 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 kDNSServiceErr_NoError (0) on success, kDNSServiceErr_BadParam on error.
*
*/
DNSSD_EXPORT
DNSServiceErrorType DNSSD_API DNSServiceConstructFullName
(
char * const fullName,
const char * const service, /* may be NULL */
const char * const regtype,
const char * const 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 union _TXTRecordRef_t { char PrivateData[16]; char *ForceNaturalAlignment; } 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 RFC 6763
* <https://tools.ietf.org/html/rfc6763#section-6.2>
*
* 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: Optional caller-supplied storage used to hold the TXTRecord data.
* This storage must remain valid for as long as
* the TXTRecordRef.
*/
DNSSD_EXPORT
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().
*
*/
DNSSD_EXPORT
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 RFC 6763
* <https://tools.ietf.org/html/rfc6763#section-6>
*
* 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
* 9 characters or fewer (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.
*/
DNSSD_EXPORT
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.
*/
DNSSD_EXPORT
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.
*/
DNSSD_EXPORT
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().
*/
DNSSD_EXPORT
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);
* ...
* memcpy(myval1, val1ptr, len1);
* memcpy(myval2, val2ptr, 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 memcpy()
* 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.
*/
DNSSD_EXPORT
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.
*/
DNSSD_EXPORT
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.
*
*/
DNSSD_EXPORT
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.
*
* itemIndex: 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
* 9 characters or fewer. 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.
*/
DNSSD_EXPORT
DNSServiceErrorType DNSSD_API TXTRecordGetItemAtIndex
(
uint16_t txtLen,
const void *txtRecord,
uint16_t itemIndex,
uint16_t keyBufLen,
char *key,
uint8_t *valueLen,
const void **value
);
#if _DNS_SD_LIBDISPATCH
/*
* DNSServiceSetDispatchQueue
*
* Allows you to schedule a DNSServiceRef on a serial dispatch queue for receiving asynchronous
* callbacks. It's the clients responsibility to ensure that the provided dispatch queue is running.
*
* A typical application that uses CFRunLoopRun or dispatch_main on its main thread will
* usually schedule DNSServiceRefs on its main queue (which is always a serial queue)
* using "DNSServiceSetDispatchQueue(sdref, dispatch_get_main_queue());"
*
* If there is any error during the processing of events, the application callback will
* be called with an error code. For shared connections, each subordinate DNSServiceRef
* will get its own error callback. Currently these error callbacks only happen
* if the daemon is manually terminated or crashes, and the error
* code in this case is kDNSServiceErr_ServiceNotRunning. The application must call
* DNSServiceRefDeallocate to free the DNSServiceRef when it gets such an error code.
* These error callbacks are rare and should not normally happen on customer machines,
* but application code should be written defensively to handle such error callbacks
* gracefully if they occur.
*
* After using DNSServiceSetDispatchQueue on a DNSServiceRef, calling DNSServiceProcessResult
* on the same DNSServiceRef will result in undefined behavior and should be avoided.
*
* Once the application successfully schedules a DNSServiceRef on a serial dispatch queue using
* DNSServiceSetDispatchQueue, it cannot remove the DNSServiceRef from the dispatch queue, or use
* DNSServiceSetDispatchQueue a second time to schedule the DNSServiceRef onto a different serial dispatch
* queue. Once scheduled onto a dispatch queue a DNSServiceRef will deliver events to that queue until
* the application no longer requires that operation and terminates it using DNSServiceRefDeallocate.
*
* service: DNSServiceRef that was allocated and returned to the application, when the
* application calls one of the DNSService API.
*
* queue: dispatch queue where the application callback will be scheduled
*
* return value: Returns kDNSServiceErr_NoError on success.
* Returns kDNSServiceErr_NoMemory if it cannot create a dispatch source
* Returns kDNSServiceErr_BadParam if the service param is invalid or the
* queue param is invalid
*/
DNSSD_EXPORT
DNSServiceErrorType DNSSD_API DNSServiceSetDispatchQueue
(
DNSServiceRef service,
dispatch_queue_t queue
);
#endif //_DNS_SD_LIBDISPATCH
#if !defined(_WIN32)
typedef void (DNSSD_API *DNSServiceSleepKeepaliveReply)
(
DNSServiceRef sdRef,
DNSServiceErrorType errorCode,
void *context
);
DNSSD_EXPORT
DNSServiceErrorType DNSSD_API DNSServiceSleepKeepalive
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
int fd,
unsigned int timeout,
DNSServiceSleepKeepaliveReply callBack,
void *context
);
#endif
/* Some C compiler cleverness. We can make the compiler check certain things for us,
* and report errors at compile-time if anything is wrong. The usual way to do this would
* be to use a run-time "if" statement or the conventional run-time "assert" mechanism, but
* then you don't find out what's wrong until you run the software. This way, if the assertion
* condition is false, the array size is negative, and the complier complains immediately.
*/
struct CompileTimeAssertionChecks_DNS_SD
{
char assert0[(sizeof(union _TXTRecordRef_t) == 16) ? 1 : -1];
};
#ifdef __cplusplus
}
#endif
#endif /* _DNS_SD_H */
