chromium/chrome/child/pdf_child_init.cc

// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "chrome/child/pdf_child_init.h"

#include "build/build_config.h"

#if BUILDFLAG(IS_WIN)
#include "base/command_line.h"
#include "base/no_destructor.h"
#include "base/win/current_module.h"
#include "base/win/iat_patch_function.h"
#include "base/win/windows_version.h"
#include "content/public/child/child_thread.h"
#include "content/public/common/content_switches.h"
#include "sandbox/policy/mojom/sandbox.mojom.h"
#include "sandbox/policy/sandbox_type.h"
#include "sandbox/policy/switches.h"
#endif

namespace {

#if BUILDFLAG(IS_WIN)
typedef decltype(::GetFontData)* GetFontDataPtr;
GetFontDataPtr g_original_get_font_data = nullptr;


DWORD WINAPI GetFontDataPatch(HDC hdc,
                              DWORD table,
                              DWORD offset,
                              LPVOID buffer,
                              DWORD length) {
  DWORD rv = g_original_get_font_data(hdc, table, offset, buffer, length);
  if (rv == GDI_ERROR && hdc) {
    HFONT font = static_cast<HFONT>(GetCurrentObject(hdc, OBJ_FONT));

    LOGFONT logfont;
    if (GetObject(font, sizeof(LOGFONT), &logfont)) {
      if (content::ChildThread::Get())
        content::ChildThread::Get()->PreCacheFont(logfont);
      rv = g_original_get_font_data(hdc, table, offset, buffer, length);
      if (content::ChildThread::Get())
        content::ChildThread::Get()->ReleaseCachedFonts();
    }
  }
  return rv;
}
#endif  // BUILDFLAG(IS_WIN)

}  // namespace

void MaybePatchGdiGetFontData() { … }