dns_sd.h

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#ifndef _DNS_SD_H
#define _DNS_SD_H
 
//Dependencies
#include "core/net.h"
#include "dns/dns_common.h"
#include "mdns/mdns_common.h"
 
//DNS-SD support
#ifndef DNS_SD_SUPPORT
   #define DNS_SD_SUPPORT DISABLED
#elif (DNS_SD_SUPPORT != ENABLED && DNS_SD_SUPPORT != DISABLED)
   #error DNS_SD_SUPPORT parameter is not valid
#endif
 
//DNS-SD tick interval
#ifndef DNS_SD_TICK_INTERVAL
   #define DNS_SD_TICK_INTERVAL 250
#elif (DNS_SD_TICK_INTERVAL < 10)
   #error DNS_SD_TICK_INTERVAL parameter is not valid
#endif
 
//Maximum number of registered services
#ifndef DNS_SD_SERVICE_LIST_SIZE
   #define DNS_SD_SERVICE_LIST_SIZE 2
#elif (DNS_SD_SERVICE_LIST_SIZE < 1)
   #error DNS_SD_SERVICE_LIST_SIZE parameter is not valid
#endif
 
//Maximum length of service name
#ifndef DNS_SD_MAX_SERVICE_NAME_LEN
   #define DNS_SD_MAX_SERVICE_NAME_LEN 16
#elif (DNS_SD_MAX_SERVICE_NAME_LEN < 1)
   #error DNS_SD_MAX_SERVICE_NAME_LEN parameter is not valid
#endif
 
//Maximum length of instance name
#ifndef DNS_SD_MAX_INSTANCE_NAME_LEN
   #define DNS_SD_MAX_INSTANCE_NAME_LEN 32
#elif (DNS_SD_MAX_INSTANCE_NAME_LEN < 1)
   #error DNS_SD_MAX_INSTANCE_NAME_LEN parameter is not valid
#endif
 
//Maximum length of the discovery-time metadata (TXT record)
#ifndef DNS_SD_MAX_METADATA_LEN
   #define DNS_SD_MAX_METADATA_LEN 128
#elif (DNS_SD_MAX_METADATA_LEN < 1)
   #error DNS_SD_MAX_METADATA_LEN parameter is not valid
#endif
 
//Default resource record TTL (cache lifetime)
#ifndef DNS_SD_DEFAULT_RR_TTL
   #define DNS_SD_DEFAULT_RR_TTL 120
#elif (DNS_SD_DEFAULT_RR_TTL < 1)
   #error DNS_SD_DEFAULT_RR_TTL parameter is not valid
#endif
 
//Forward declaration of DnsSdContext structure
struct _DnsSdContext;
#define DnsSdContext struct _DnsSdContext
 
//C++ guard
#ifdef __cplusplus
extern "C" {
#endif
 
 
typedef void (*DnsSdStateChangeCallback)(DnsSdContext *context,
   NetInterface *interface, MdnsState state);
 
 
typedef struct
{
   NetInterface *interface;                   
   uint_t numAnnouncements;                   
   uint32_t ttl;                              
   DnsSdStateChangeCallback stateChangeEvent; 
} DnsSdSettings;
 
 
typedef struct
{
   char_t name[DNS_SD_MAX_SERVICE_NAME_LEN + 1]; 
   uint16_t priority;                            
   uint16_t weight;                              
   uint16_t port;                                
   uint8_t metadata[DNS_SD_MAX_METADATA_LEN];    
   size_t metadataLength;                        
} DnsSdService;
 
 
struct _DnsSdContext
{
   DnsSdSettings settings;                                
   bool_t running;                                        
   MdnsState state;                                       
   bool_t conflict;                                       
   bool_t tieBreakLost;                                   
   systime_t timestamp;                                   
   systime_t timeout;                                     
   uint_t retransmitCount;                                
   char_t instanceName[DNS_SD_MAX_INSTANCE_NAME_LEN + 1]; 
   DnsSdService serviceList[DNS_SD_SERVICE_LIST_SIZE];    
};
 
 
//Tick counter to handle periodic operations
extern systime_t dnsSdTickCounter;
 
//DNS-SD related functions
void dnsSdGetDefaultSettings(DnsSdSettings *settings);
error_t dnsSdInit(DnsSdContext *context, const DnsSdSettings *settings);
error_t dnsSdStart(DnsSdContext *context);
error_t dnsSdStop(DnsSdContext *context);
MdnsState dnsSdGetState(DnsSdContext *context);
 
error_t dnsSdSetInstanceName(DnsSdContext *context, const char_t *instanceName);
 
error_t dnsSdRegisterService(DnsSdContext *context, const char_t *serviceName,
   uint16_t priority, uint16_t weight, uint16_t port, const char_t *metadata);
 
error_t dnsSdUnregisterService(DnsSdContext *context, const char_t *serviceName);
 
uint_t dnsSdGetNumServices(DnsSdContext *context);
error_t dnsSdStartProbing(DnsSdContext *context);
 
void dnsSdTick(DnsSdContext *interface);
void dnsSdLinkChangeEvent(DnsSdContext *interface);
 
//C++ guard
#ifdef __cplusplus
}
#endif
 
#endif