blob: a004c5a3686c683bfd865d73b3fde01b3d3a4e0f [file] [log] [blame]
// Copyright 2019 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 <dwrite.h>
#include <dwrite_2.h>
#include <wrl.h>
#include "base/macros.h"
#include "base/memory/read_only_shared_memory_region.h"
#include "base/memory/singleton.h"
#include "base/synchronization/waitable_event.h"
#include "content/common/content_export.h"
namespace base {
template <typename T>
class NoDestructor;
namespace content {
// Singleton class which encapsulates building the font unique name table lookup
// once, then serving the built table as a ReadOnlySharedMemoryRegion. Receives
// requests for accessing this table from DWriteFontProxyImpl after Mojo IPC
// calls from the renderer.
class CONTENT_EXPORT DWriteFontLookupTableBuilder {
static DWriteFontLookupTableBuilder* GetInstance();
void SetSlowDownIndexingForTesting(bool);
// Needed to trigger rebuilding the lookup table, when testing using
// slowed-down indexing. Otherwise, the test methods would use the already
// cached lookup table.
void ResetLookupTableForTesting();
// Retrieve the prepared memory region if it is available.
// EnsureFontUniqueNameTable() should be checked before. This method hits an
// assertion otherwise.
base::ReadOnlySharedMemoryRegion DuplicatedMemoryRegion();
// Wait for the internal WaitableEvent to be signaled if needed and return
// true if the font unique name lookup table was successfully constructed.
bool EnsureFontUniqueNameTable();
friend class base::NoDestructor<DWriteFontLookupTableBuilder>;
void BuildFontUniqueNameTable();
bool IsFontUniqueNameTableValid();
// Checks if the unique font table has been built already, and if not, builds
// it by enumerating fonts from the collection, extracting their file
// locations, ttc indices and names.
void InitializeDirectWrite();
// This can only be replaced from the construction sequence. Once
// font_table_built_ is signaled, it can be read from everywhere.
base::MappedReadOnlyRegion font_table_memory_;
bool direct_write_initialized_ = false;
Microsoft::WRL::ComPtr<IDWriteFontCollection> collection_;
Microsoft::WRL::ComPtr<IDWriteFactory2> factory2_;
bool slow_down_indexing_for_testing_ = false;
} // namespace content