Added NetworkInterface::network_prefix

net/base/net_util.cc

Index: net/base/net_util.cc
diff --git a/net/base/net_util.cc b/net/base/net_util.cc
index dd0826c6a5405945e381368f4eed8a8f49a5f01e..dd4452cc99907a0b864f09cc2a6d451485f63361 100644
--- a/net/base/net_util.cc
+++ b/net/base/net_util.cc
@@ -2142,6 +2142,8 @@ bool IsLocalhost(const std::string& host) {
   return false;
 }
 
+#if defined(OS_ANDROID)
+
 NetworkInterface::NetworkInterface() {
 }
 
@@ -2150,7 +2152,42 @@ NetworkInterface::NetworkInterface(const std::string& name,
     : name(name), address(address) {
 }
 
+#else  // OS_ANDROID
+
+NetworkInterface::NetworkInterface() : network_prefix(0) {
+}
+
+NetworkInterface::NetworkInterface(const std::string& name,
+                                   const IPAddressNumber& address,
+                                   uint8 network_prefix)
+    : name(name), address(address), network_prefix(network_prefix) {
+}
+
+#endif  // OS_ANDROID
+
 NetworkInterface::~NetworkInterface() {
 }
 
+unsigned CommonPrefixLength(const IPAddressNumber& a1,
+                            const IPAddressNumber& a2) {
+  DCHECK_EQ(a1.size(), a2.size());
+  for (size_t i = 0; i < a1.size(); ++i) {
+    unsigned diff = a1[i] ^ a2[i];
+    if (!diff)
+      continue;
+    for (unsigned j = 0; j < CHAR_BIT; ++j) {
+      if (diff & (1 << (CHAR_BIT - 1)))
+        return i * CHAR_BIT + j;
+      diff <<= 1;
+    }
+    NOTREACHED();
+  }
+  return a1.size() * CHAR_BIT;
+}
+
+unsigned MaskPrefixLength(const IPAddressNumber& mask) {
+  IPAddressNumber all_ones(mask.size(), 0xFF);
+  return CommonPrefixLength(mask, all_ones);
+}
+
 }  // namespace net