winamp/Src/replicant/jnetlib/asyncdns.h

/*
** JNetLib
** Copyright (C) 2000-2007 Nullsoft, Inc.
** Author: Justin Frankel
** File: asyncdns.h - JNL portable asynchronous DNS interface
** License: see jnetlib.h
**
** Usage:
**   1. Create JNL_AsyncDNS object, optionally with the number of cache entries.
**   2. call resolve() to resolve a hostname into an address. The return value of 
**      resolve is 0 on success (host successfully resolved), 1 on wait (meaning
**      try calling resolve() with the same hostname in a few hundred milliseconds 
**      or so), or -1 on error (i.e. the host can't resolve).
**   3. call reverse() to do reverse dns (ala resolve()).
**   4. enjoy.
*/

#ifndef _ASYNCDNS_H_
#define _ASYNCDNS_H_

#include "netinc.h"

struct cache_entry;

#define JNL_AUTODNS ((JNL_AsyncDNS *)-1)
enum
{
	DNS_RESOLVE_UNRESOLVABLE = -1,
	DNS_RESOLVE_SUCCESS      = 0,
	DNS_RESOLVE_WAIT         = 1,
};

enum
{
	DNS_REVERSE_UNRESOLVABLE = -1,
	DNS_REVERSE_SUCCESS      = 0,
	DNS_REVERSE_WAIT         = 1,
};

class JNL_AsyncDNS
{
public:
	JNL_AsyncDNS( int max_cache_entries = 64 );
	~JNL_AsyncDNS();

	int resolve( const char *hostname, unsigned short port, addrinfo **addr, int sockettype ); // return 0 on success, 1 on wait, -1 on unresolvable
	static int resolvenow( const char *hostname, unsigned short port, addrinfo **addr, int sockettype ); // return 0 on success, -1 on unresolvable
	//int reverse(unsigned long addr, char *hostname, size_t hostnameSize); // return 0 on success, 1 on wait, -1 on unresolvable. hostname must be at least 256 bytes.

private:
	cache_entry *m_cache;
	int m_cache_size;
	volatile int m_thread_kill;

#ifdef _WIN32
	HANDLE m_thread;
	static unsigned long WINAPI _threadfunc( LPVOID _d );
#else
	pthread_t m_thread;
	static unsigned int _threadfunc( void *_d );
#endif

	void makesurethreadisrunning( void );
};

#endif //_ASYNCDNS_H_