读取纯真IP数据库

#define  _CRT_SECURE_NO_WARNINGS
#include 
#include 
#include 
#include 
using namespace std;

char *ptr = NULL;						//ptr of image//内存映射文件
char *p = NULL;							//point to index//索引区
unsigned int total;						//ip count

inline void Load(void)
{
	HANDLE		hnd;					//file handle
	DWORD		NumberOfBytesRead;		//len
	char		text[2048];				//patch
	char		*temp;
	unsigned int len;

	//get patch
	if( !GetModuleFileName(0, text, 2048))
		return;

	temp = strrchr(text, 92);			// 92 = '\'
	*(temp + 1) = NULL;
	strcat(temp, "QQwry.dat");

	//CreateFile
	hnd = CreateFile(text, GENERIC_READ, FILE_SHARE_READ, NULL,
		OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
	if(INVALID_HANDLE_VALUE == hnd)
	{
		::MessageBox(NULL, text, "不能打开文件!", NULL);
		return;
	}

	//get len
	len = SetFilePointer(hnd, NULL, NULL, FILE_END);
	SetFilePointer(hnd, NULL, NULL, FILE_BEGIN);

	//malloc
	ptr = (char*)malloc(len + 9);
	if(!ptr)
	{
		CloseHandle(hnd);
		::MessageBox(NULL, "不能分配内存!", NULL, NULL);
		return;
	}

	//read
	if(!ReadFile(hnd, ptr, len, &NumberOfBytesRead, NULL))
	{
		CloseHandle(hnd);
		free(ptr);
		::MessageBox(NULL, text, "不能读入文件!", NULL);
		return;
	}
	CloseHandle(hnd);

	//calc total - 1
	total = (*((unsigned int*)ptr + 1) - *(unsigned int*)ptr);

	//check file
	if(total % 7 != 0)
	{
		free(ptr);
		::MessageBox(NULL, text, "QQwry.dat文件有损坏!", NULL);
		return;
	}

	total /= 7;
	++total;
	p = ptr + *(unsigned int*)ptr;  //ptr of index area
}

inline unsigned int get_3b(const char *mem)
{
	return 0x00ffffff & *(unsigned int*)(mem);
}

inline unsigned int str2ip(const char *lp)
{
	unsigned int iIP = 0;
	unsigned int tmpIP = 0;

	while(*lp)
	{
		if('.' == *lp)
		{
			iIP = 256 * iIP + tmpIP;
			tmpIP = 0;
		}
		else
		{
			tmpIP = 10 * tmpIP + *lp - '0';
		}
		++lp;
	}

	iIP = 256 * iIP + tmpIP;
	return iIP;
}

string _GetAddress(string IPstr)
{
	string ret;
	if(NULL == p)
	{
		ret = "";
		return ret;
	}

	unsigned int ip = str2ip(IPstr.c_str());
	char *now_p;

	unsigned int begin = 0, end = total;
	while(true)
	{
		if( begin >= end - 1 )
		{
			break;
		}
		if( ip < *(unsigned int*)(p + (begin + end)/2 * 7))
		{
			end = (begin + end) / 2;
		}
		else
		{
			begin = (begin + end) / 2;
		}
	}

	unsigned int temp = get_3b(p + 7 * begin + 4);
	if(ip <= *(unsigned int*)(ptr + temp))		//ok, found
	{
		now_p = ptr + temp + 4;
		if( 0x01 == *now_p )					//如果0x01跳过去找国家
		{	
			now_p = ptr + get_3b(now_p + 1);
		}
		//country
		if( 0x02 == *now_p )					//如果国家0x02再跳
		{
			ret = ptr + get_3b(now_p + 1);
			now_p += 4;
		}
		else
		{
			ret = now_p;
			for(; *now_p; ++now_p)
				;
			++now_p;
		}
		//local
		if( 0x02 == *now_p ) //找到国家以后还发现0x02跳过去找地区
		{	
			ret += ptr + get_3b(now_p + 1);
		}
		else
		{
			ret += now_p;
		}
	}
	else
	{
		ret = "未知数据";
	}
	return ret;
}

int main(void)
{
	Load();
	string ip;
	while (cin >> ip)
	{
		cout << _GetAddress(ip) << endl;
	}
	return 0;
}

http://hzy3774.iteye.com/blog/1851364

http://hzy3774.iteye.com/blog/1851364