Allow custom deleters to opt out of self reset checks for scoped_ptr.

net/ssl/openssl_client_key_store.cc

 // Copyright (c) 2013 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 "net/ssl/openssl_client_key_store.h"
 
 #include <openssl/evp.h>
 #include <openssl/x509.h>
+#include <algorithm>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "net/cert/x509_certificate.h"
 
 namespace net {
 
 namespace {
 
 // Return the EVP_PKEY holding the public key of a given certificate.
@@ skipping 24 matching lines @@
 }
 
 OpenSSLClientKeyStore::KeyPair::~KeyPair() {
 }
 
 OpenSSLClientKeyStore::KeyPair::KeyPair(const KeyPair& other)
     : public_key(EVP_PKEY_dup(other.public_key.get())),
       private_key(EVP_PKEY_dup(other.private_key.get())) {
 }
 
-void OpenSSLClientKeyStore::KeyPair::operator=(const KeyPair& other) {
-  // Use a temporary ScopedEVP_PKEY because scoped_ptr does not allow resetting
-  // to the current value, even though it's safe here.
-  crypto::ScopedEVP_PKEY public_key_tmp(EVP_PKEY_dup(other.public_key.get()));
-  crypto::ScopedEVP_PKEY private_key_tmp(EVP_PKEY_dup(other.private_key.get()));
-  public_key.reset();
-  public_key = public_key_tmp.Pass();
-  private_key.reset();
-  private_key = private_key_tmp.Pass();
+void OpenSSLClientKeyStore::KeyPair::operator=(KeyPair other) {
+  this->swap(other);
+}
+
+// Intentionally pass by value, in order to use the copy-and-swap idiom.

[pneubeck (no reviews), 2014/10/07 09:30:09]

should this comment better be at the operator= function?

[dcheng, 2014/10/07 22:40:37]

I'm ambivalent on this. I felt like it was better to describe the idiom where it
actually appeared, but I don't think putting it in the header is wrong either.
So moved. Done.

+void OpenSSLClientKeyStore::KeyPair::swap(KeyPair& other) {
+  using std::swap;
+  swap(public_key, other.public_key);
+  swap(private_key, other.private_key);
 }
 
 int OpenSSLClientKeyStore::FindKeyPairIndex(EVP_PKEY* public_key) {
   if (!public_key)
     return -1;
   for (size_t n = 0; n < pairs_.size(); ++n) {
     if (EVP_PKEY_cmp(pairs_[n].public_key.get(), public_key) == 1)
       return static_cast<int>(n);
   }
   return -1;
@@ skipping 44 matching lines @@
   pairs_.clear();
 }
 
 OpenSSLClientKeyStore* OpenSSLClientKeyStore::GetInstance() {
   return Singleton<OpenSSLClientKeyStore>::get();
 }
 
 }  // namespace net