Use base::StringPiece for input parameters in Encryptor, rather than std::string

crypto/encryptor.cc

 // Copyright (c) 2011 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 "crypto/encryptor.h"
 
 #include "base/logging.h"
 #include "build/build_config.h"
 
 // Include headers to provide bswap for all platforms.
@@ skipping 16 matching lines @@
 #define hton_64(x) bswap_64(x)
 #else
 #define ntoh_64(x) (x)
 #define hton_64(x) (x)
 #endif
 
 namespace crypto {
 
 /////////////////////////////////////////////////////////////////////////////
 // Encyptor::Counter Implementation.
-Encryptor::Counter::Counter(const std::string& counter) {
+Encryptor::Counter::Counter(const base::StringPiece& counter) {
   CHECK(sizeof(counter_) == counter.length());
 
   memcpy(&counter_, counter.data(), sizeof(counter_));
 }
 
 Encryptor::Counter::~Counter() {
 }
 
 bool Encryptor::Counter::Increment() {
   uint64 low_num = ntoh_64(counter_.components64[1]);
@@ skipping 15 matching lines @@
   memcpy(buf_ptr, &counter_, sizeof(counter_));
 }
 
 size_t Encryptor::Counter::GetLengthInBytes() const {
   return sizeof(counter_);
 }
 
 /////////////////////////////////////////////////////////////////////////////
 // Partial Encryptor Implementation.
 
-bool Encryptor::SetCounter(const std::string& counter) {
+bool Encryptor::SetCounter(const base::StringPiece& counter) {
   if (mode_ != CTR)
     return false;
   if (counter.length() != 16u)
     return false;
 
   counter_.reset(new Counter(counter));
   return true;
 }
 
 bool Encryptor::GenerateCounterMask(size_t plaintext_len,
@@ skipping 27 matching lines @@
   DCHECK_EQ(CTR, mode_);
   const uint8* plaintext_ptr = reinterpret_cast<const uint8*>(plaintext);
   const uint8* mask_ptr = reinterpret_cast<const uint8*>(mask);
   uint8* ciphertext_ptr = reinterpret_cast<uint8*>(ciphertext);
 
   for (size_t i = 0; i < plaintext_len; ++i)
     ciphertext_ptr[i] = plaintext_ptr[i] ^ mask_ptr[i];
 }
 
 }  // namespace crypto