Refactor EnsureOpenSSLInit and openssl_util into base

base/openssl_util.h

 // Copyright (c) 2010 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.
 
 #ifndef BASE_OPENSSL_UTIL_H_
 #define BASE_OPENSSL_UTIL_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/tracked.h"
 
 namespace base {
 
+// A helper class that takes care of destroying OpenSSL objects when it goes out
+// of scope.
+template <typename T, void (*destructor)(T*)>
+class ScopedSSL {

[wtc, 2010/11/16 15:35:07]

This template class should be named ScopedOpenSSL.  Would
that be too wordy?

[joth, 2010/11/16 16:07:19]

Done.

+ public:
+  explicit ScopedSSL(T* ptr_) : ptr_(ptr_) { }
+  ~ScopedSSL() { if (ptr_) (*destructor)(ptr_); }
+
+  T* get() const { return ptr_; }
+
+ private:
+  T* ptr_;
+};
+
 // Provides a buffer of at least MIN_SIZE bytes, for use when calling OpenSSL's
 // SHA256, HMAC, etc functions, adapting the buffer sizing rules to meet those
 // of the our base wrapper APIs.
 // This allows the library to write directly to the caller's buffer if it is of
 // sufficient size, but if not it will write to temporary |min_sized_buffer_|
 // of required size and then its content is automatically copied out on
 // destruction, with truncation as appropriate.
 template<int MIN_SIZE>
 class ScopedOpenSSLSafeSizeBuffer {
  public:
@@ skipping 20 matching lines @@
   unsigned char* output_;
   size_t output_len_;
 
   // Temporary buffer writen into in the case where the caller's
   // buffer is not of sufficient size.
   unsigned char min_sized_buffer_[MIN_SIZE];
 
   DISALLOW_COPY_AND_ASSIGN(ScopedOpenSSLSafeSizeBuffer);
 };
 
+// Initialize OpenSSL if it isn't already initialized. This must be called
+// before any other OpenSSL functions.
+// This function is thread-safe, and OpenSSL will only ever be initialized once.
+// OpenSSL will be properly shut down on program exit.
+void EnsureOpenSSLInit();
+
 // Drains the OpenSSL ERR_get_error stack. On a debug build the error codes
 // are send to VLOG(1), on a release build they are disregarded.
 void ClearOpenSSLERRStack();
 
 }  // namespace base
 
 #endif  // BASE_OPENSSL_UTIL_H_