From 96f3c7312032c56387fc774a13901fc32d341ba1 Mon Sep 17 00:00:00 2001
From: Pavel Odintsov <pavel.odintsov@gmail.com>
Date: Sat, 14 Feb 2015 21:01:42 +0300
Subject: [PATCH] Complete test solution for CIDR issue

---
 tests/test_cidr.cpp | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/tests/test_cidr.cpp b/tests/test_cidr.cpp
index ab7feb7..fd10228 100644
--- a/tests/test_cidr.cpp
+++ b/tests/test_cidr.cpp
@@ -7,6 +7,16 @@
 #include <arpa/inet.h>
 #include <iostream>
 
+uint32_t convert_cidr_to_binary_netmask(unsigned int cidr) {
+    uint32_t binary_netmask = 0xFFFFFFFF; 
+    binary_netmask = binary_netmask << ( 32 - cidr );
+    // htonl from host byte order to network
+    // ntohl from network byte order to host
+
+    // We need network byte order at output 
+    return htonl(binary_netmask);
+}
+
 uint32_t convert_ip_as_string_to_uint(std::string ip) {
     struct in_addr ip_addr;
     inet_aton(ip.c_str(), &ip_addr);
@@ -16,9 +26,16 @@ uint32_t convert_ip_as_string_to_uint(std::string ip) {
 }
 
 int main() {
+    uint32_t network_zero = convert_ip_as_string_to_uint("10.10.10.0");
+    uint32_t network_200 = convert_ip_as_string_to_uint("10.10.10.200"); 
+
+    uint32_t binary_netmask = convert_cidr_to_binary_netmask(24);
+
+    uint32_t generated_subnet_address = network_200 & binary_netmask; 
+
     std::cout<<"network byte order"<<std::endl;
-    std::cout<<"10.10.10.200/24\tnetwork byte order:"<<convert_ip_as_string_to_uint("10.10.10.200")<<" host byte order:"<<ntohl(convert_ip_as_string_to_uint("10.10.10.200"))<<std::endl;
-    std::cout<<"10.10.10.0/24\tnetwork byte order:"  <<convert_ip_as_string_to_uint("10.10.10.0")<<" host byte order:"<<ntohl(convert_ip_as_string_to_uint("10.10.10.0"))<<std::endl;
+    std::cout<<"10.10.10.200/24\tnetwork byte order:"<<network_200 <<" host byte order:"<<ntohl(network_200)<<std::endl;
+    std::cout<<"10.10.10.0/24\tnetwork byte order:"  <<network_zero<<" host byte order:"<<ntohl(network_zero)<<std::endl;
     
-     
+    std::cout<<"generated \tnetwork byte order:"  <<generated_subnet_address<<" host byte order:"<<ntohl(generated_subnet_address)<<std::endl; 
 }