ruleset_dealer.h | Explore in Territory

// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_SUBRESOURCE_FILTER_CORE_COMMON_RULESET_DEALER_H_
#define COMPONENTS_SUBRESOURCE_FILTER_CORE_COMMON_RULESET_DEALER_H_

#include "base/files/file.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/sequence_checker.h"

namespace subresource_filter {

class MemoryMappedRuleset;

// Memory maps the subresource filtering ruleset file, and makes it available to
// all call sites of GetRuleset() within the current process.
//
// Although most OS'es will take care of memory mapping pages of the ruleset
// only on-demand, and of swapping out pages eagerly when they are no longer
// used, this class has extra logic to make sure memory is conserved as much as
// possible, and syscall overhead is minimized:
//
//   * The ruleset is only memory mapped on-demand the first time GetRuleset()
//     is called, and unmapped once the last caller drops its reference to it.
//
//   * If the ruleset is used by multiple call sites within the same process,
//     they will use the same, cached, MemoryMappedRuleset instance, and will
//     not call mmap() multiple times.
//
class RulesetDealer { … };

}  // namespace subresource_filter

#endif  // COMPONENTS_SUBRESOURCE_FILTER_CORE_COMMON_RULESET_DEALER_H_
chromium/components/subresource_filter/core/common/ruleset_dealer.h
