Added folly::hint_emplace_iterator to folly/Iterator.h

[folly.git] / folly / IPAddressV6.cpp

diff --git a/folly/IPAddressV6.cpp b/folly/IPAddressV6.cpp
index 5607a4bfcb37e61eef7d7f7b2e177a9594a4426a..6f1eb5958996c5f12bb16204a6c2a3398ddf26de 100644 (file)
--- a/folly/IPAddressV6.cpp
+++ b/folly/IPAddressV6.cpp
@@ -173,6 +173,34 @@ void IPAddressV6::setFromBinary(ByteRange bytes) {
   scope_ = 0;
 }
 
+// static
+IPAddressV6 IPAddressV6::fromInverseArpaName(const std::string& arpaname) {
+  auto piece = StringPiece(arpaname);
+  if (!piece.removeSuffix(".ip6.arpa")) {
+    throw IPAddressFormatException(sformat(
+        "Invalid input. Should end with 'ip6.arpa'. Got '{}'", arpaname));
+  }
+  std::vector<StringPiece> pieces;
+  split(".", piece, pieces);
+  if (pieces.size() != 32) {
+    throw IPAddressFormatException(sformat("Invalid input. Got '{}'", piece));
+  }
+  std::array<char, IPAddressV6::kToFullyQualifiedSize> ip;
+  size_t pos = 0;
+  int count = 0;
+  for (size_t i = 1; i <= pieces.size(); i++) {
+    ip[pos] = pieces[pieces.size() - i][0];
+    pos++;
+    count++;
+    // add ':' every 4 chars
+    if (count == 4 && pos < ip.size()) {
+      ip[pos++] = ':';
+      count = 0;
+    }
+  }
+  return IPAddressV6(folly::range(ip));
+}
+
 // public
 IPAddressV4 IPAddressV6::createIPv4() const {
   if (!isIPv4Mapped()) {
@@ -397,6 +425,19 @@ string IPAddressV6::toFullyQualified() const {
   return detail::fastIpv6ToString(addr_.in6Addr_);
 }
 
+// public
+string IPAddressV6::toInverseArpaName() const {
+  constexpr folly::StringPiece lut = "0123456789abcdef";
+  std::array<char, 32> a;
+  int j = 0;
+  for (int i = 15; i >= 0; i--) {
+    a[j] = (lut[bytes()[i] & 0xf]);
+    a[j + 1] = (lut[bytes()[i] >> 4]);
+    j += 2;
+  }
+  return sformat("{}.ip6.arpa", join(".", a));
+}
+
 // public
 uint8_t IPAddressV6::getNthMSByte(size_t byteIndex) const {
   const auto highestIndex = byteCount() - 1;