读取纯真IP数据库

#define  _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <string>
#include <stdlib.h>
#include <windows.h>
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;
}