azhai · December 21, 2016 06:45 · Jan 18, 2014 · Jul 9, 2013
diff --git a/ip_address → ip_address.py b/ip_address → ip_address.py
diff --git a/ip_address b/ip_address
@@ -0,0 +1,54 @@
+# -*- coding: utf-8 -*-
+"""
+需要存放IP段起止地址的二进制文件cnips.dat
+"""
+
+import os, os.path
+from IPy import IP
+
+
+def binary_search(total, callback, *args):
+    """ 二分（折半）查找算法 """
+    step = total
+    offset = 0
+    sign = 1
+    while True:
+        step = (step + 1) / 2
+        offset += sign * step
+        sign = callback(offset, *args)
+        if sign is 0 or step <= 1:
+            break
+    return sign is 0
+
+
+def compare_ip(offset, ip, fp):
+    fp.seek((offset - 1) * 8)
+    start_ip = fp.read(4) #读取之后0-4个字节
+    end_ip = fp.read(4) #读取之后4-8个字节
+    start_ip, end_ip = start_ip.encode('hex'), end_ip.encode('hex')
+    #指出下次偏移的方向
+    if ip < start_ip:
+        return -1
+    elif ip > end_ip:
+        return 1
+    else:
+        return 0 #在IP段范围内（含两端）
+
+
+def ip_in_china(ip_address):
+    #IP段数据文件，每个IP表示成一个8位hex整数，不足8位的前面补0
+    datfile = 'cnips.dat'
+    total = os.stat(datfile).st_size / 8 #IP段总数
+    #将要判断的IP转为8位hex整数
+    ip = IP(ip_address).strHex()[2:]
+    fp = open(datfile, 'rb')
+    #比较IP并决定方向
+    result = binary_search(total, compare_ip, ip, fp)
+    fp.close()
+    return result
+
+
+
+if __name__ == "__main__":
+    for ip in ['49.114.165.195', '211.137.180.236', '175.223.16.46', '175.223.52.32', '219.74.86.136', '223.62.178.66', '223.33.184.117', '222.102.171.135', '113.162.202.32', '37.131.68.47', '178.77.154.240', '186.204.91.244', '119.139.14.70', '103.1.30.66', '192.168.102.42', '171.208.114.19', '27.42.26.56', '49.114.165.195', '211.137.180.236', '175.223.16.46', '175.223.52.32', '219.74.86.136', '223.62.178.66', '223.33.184.117', '222.102.171.135', '113.162.202.32', '37.131.68.47', '178.77.154.240', '186.123.135.229', '61.18.254.113', '210.91.142.47']:
+        print ip, int(ip_in_china(ip))