src/net/instaweb/rewriter/public/process_context.h

// Copyright 2011 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Author: jmarantz@google.com (Joshua Marantz)

#ifndef NET_INSTAWEB_REWRITER_PUBLIC_PROCESS_CONTEXT_H_
#define NET_INSTAWEB_REWRITER_PUBLIC_PROCESS_CONTEXT_H_

#include "pagespeed/kernel/base/basictypes.h"
#include "pagespeed/kernel/base/scoped_ptr.h"

namespace pagespeed { namespace js { struct JsTokenizerPatterns; } };

namespace net_instaweb {

// This class encapsulates the initialization and cleanup of static and
// global variables across Pagespeed Automatic.  The usage of this class
// is optional, but can help with cleaning up valgrind messages.
//
// It is up to the user to ensure the destructor is called at an appropriate
// time in their flow.  There is no statically constructed object declared
// in mem_clean_up.cc, although this class can be instantiated statically
// if that's the best mechanism in the environment.
class ProcessContext {
 public:
  ProcessContext();
  ~ProcessContext();

  // Returns a js_tokenizer_patterns object that was allocated by the
  // ProcessContext constructor, once per process startup.  The reason
  // to manage this object this way, as opposed to constructing it
  // from the factory, is to speed up tests, where factories are
  // constructed and destroyed for every test method.
  // JsTokenizerPatterns requires compiles multiple regular
  // expressions on construction, and this takes a significant amount
  // of time in debug builds.
  const pagespeed::js::JsTokenizerPatterns* js_tokenizer_patterns() const {
    return js_tokenizer_patterns_.get();
  }

 private:
  scoped_ptr<pagespeed::js::JsTokenizerPatterns> js_tokenizer_patterns_;

  DISALLOW_COPY_AND_ASSIGN(ProcessContext);
};

}  // namespace net_instaweb

#endif  // NET_INSTAWEB_REWRITER_PUBLIC_PROCESS_CONTEXT_H_