Punycode encoder/decoder: separate core and parts that depend on UTF8

encoder/decoder


Swift SVN r20307

lib/Basic/PunycodeUTF8.cpp

@@ -0,0 +1,52 @@
+//===--- PunycodeUTF8.cpp - Unicode to Punycode transcoding -----*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See http://swift.org/LICENSE.txt for license information
+// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#include "swift/Basic/Punycode.h"
+#include "llvm/Support/ConvertUTF.h"
+#include <vector>
+
+using namespace swift;
+
+bool Punycode::encodePunycodeUTF8(StringRef InputUTF8,
+                                  std::string &OutPunycode) {
+  std::vector<uint32_t> InputCodePoints(InputUTF8.size());
+  const UTF8 *SourceStart = reinterpret_cast<const UTF8 *>(InputUTF8.data());
+  UTF32 *TargetStart = InputCodePoints.data();
+  auto ConvStatus = ConvertUTF8toUTF32(
+      &SourceStart, SourceStart + InputUTF8.size(), &TargetStart,
+      InputCodePoints.data() + InputCodePoints.size(), strictConversion);
+  if (ConvStatus != conversionOK)
+    return false;
+  return encodePunycode(InputCodePoints, OutPunycode);
+}
+
+bool Punycode::decodePunycodeUTF8(StringRef InputPunycode,
+                                  std::string &OutUTF8) {
+  std::vector<uint32_t> OutCodePoints;
+  if (!decodePunycode(InputPunycode, OutCodePoints))
+    return false;
+
+  const size_t SizeUpperBound = OutCodePoints.size() * 4;
+  std::vector<UTF8> Result(SizeUpperBound);
+  const UTF32 *SourceStart = OutCodePoints.data();
+  UTF8 *TargetStart = Result.data();
+  auto ConvStatus = ConvertUTF32toUTF8(
+      &SourceStart, SourceStart + OutCodePoints.size(), &TargetStart,
+      Result.data() + Result.size(), strictConversion);
+  if (ConvStatus != conversionOK) {
+    OutUTF8.clear();
+    return false;
+  }
+  OutUTF8 = std::string(Result.data(), TargetStart);
+  return true;
+}
+