Unify UUID/GUID generation code across base and blink

base/guid_posix.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "base/guid.h"
-
-#include <stdint.h>
-
-#include "base/rand_util.h"
-#include "base/strings/stringprintf.h"
-
-namespace base {
-
-std::string GenerateGUID() {
-  uint64_t sixteen_bytes[2] = {base::RandUint64(), base::RandUint64()};
-
-  // Set the GUID to version 4 as described in RFC 4122, section 4.4.
-  // The format of GUID version 4 must be xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx,
-  // where y is one of [8, 9, A, B].
-
-  // Clear the version bits and set the version to 4:
-  sixteen_bytes[0] &= 0xffffffffffff0fffULL;
-  sixteen_bytes[0] |= 0x0000000000004000ULL;
-
-  // Set the two most significant bits (bits 6 and 7) of the
-  // clock_seq_hi_and_reserved to zero and one, respectively:
-  sixteen_bytes[1] &= 0x3fffffffffffffffULL;
-  sixteen_bytes[1] |= 0x8000000000000000ULL;
-
-  return RandomDataToGUIDString(sixteen_bytes);
-}
-
-// TODO(cmasone): Once we're comfortable this works, migrate Windows code to
-// use this as well.
-std::string RandomDataToGUIDString(const uint64_t bytes[2]) {
-  return StringPrintf("%08X-%04X-%04X-%04X-%012llX",
-                      static_cast<unsigned int>(bytes[0] >> 32),
-                      static_cast<unsigned int>((bytes[0] >> 16) & 0x0000ffff),
-                      static_cast<unsigned int>(bytes[0] & 0x0000ffff),
-                      static_cast<unsigned int>(bytes[1] >> 48),
-                      bytes[1] & 0x0000ffffffffffffULL);
-}
-
-}  // namespace base