blob: 2f3cd0b8d7e2144cfa87a1ddd7aefe8130c0f43a [file] [log] [blame]
// Copyright 2017 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 "headless/public/util/fontconfig.h"
// Should be included before freetype.h.
#include <ft2build.h>
#include <dirent.h>
#include <fontconfig/fontconfig.h>
#include <freetype/freetype.h>
#include <set>
#include <string>
#include "base/logging.h"
namespace headless {
namespace {
void GetFontFileNames(const FcFontSet* font_set,
std::set<std::string>* file_names) {
if (font_set == NULL)
for (int i = 0; i < font_set->nfont; ++i) {
FcPattern* pattern = font_set->fonts[i];
FcValue font_file;
if (FcPatternGet(pattern, "file", 0, &font_file) == FcResultMatch) {
file_names->insert(reinterpret_cast<const char*>(font_file.u.s));
} else {
VLOG(1) << "Failed to find filename.";
FcConfig* g_config = nullptr;
} // namespace
void InitFonts(const char* fontconfig_path) {
// The following is roughly equivalent to calling FcInit(). We jump through
// a bunch of hoops here to avoid using fontconfig's directory scanning
// logic. The problem with fontconfig is that it follows symlinks when doing
// recursive directory scans.
// The approach below ignores any <dir>...</dir> entries in fonts.conf. This
// is deliberate. Specifying dirs is problematic because they're either
// absolute or relative to our process's current working directory which
// could be anything. Instead we assume that all font files will be in the
// same directory as fonts.conf. We'll scan + load them here.
FcConfig* config = FcConfigCreate();
g_config = config;
// FcConfigParseAndLoad is a seriously goofy function. Depending on whether
// name passed in begins with a slash, it will treat it either as a file name
// to be found in the directory where it expects to find the font
// configuration OR it will will treat it as a directory where it expects to
// find fonts.conf. The latter behavior is the one we want. Passing
// fontconfig_path via the environment is a quick and dirty way to get
// uniform behavior regardless whether it's a relative path or not.
setenv("FONTCONFIG_PATH", fontconfig_path, 1);
CHECK(FcConfigParseAndLoad(config, nullptr, FcTrue))
<< "Failed to load font configuration. FONTCONFIG_PATH="
<< fontconfig_path;
DIR* fc_dir = opendir(fontconfig_path);
CHECK(fc_dir) << "Failed to open font directory " << fontconfig_path << ": "
<< strerror(errno);
// The fonts must be loaded in a consistent order. This makes rendered results
// stable across runs, otherwise replacement font picks are random
// and cause flakiness.
std::set<std::string> fonts;
struct dirent *result;
while ((result = readdir(fc_dir))) {
for (const std::string& font : fonts) {
const std::string full_path = fontconfig_path + ("/" + font);
struct stat statbuf;
CHECK_EQ(0, stat(full_path.c_str(), &statbuf))
<< "Failed to stat " << full_path << ": " << strerror(errno);
if (S_ISREG(statbuf.st_mode)) {
// FcConfigAppFontAddFile will silently ignore non-fonts.
config, reinterpret_cast<const FcChar8*>(full_path.c_str()));
// Retrieve font from both of fontconfig's font sets for pre-loading.
std::set<std::string> font_files;
GetFontFileNames(FcConfigGetFonts(NULL, FcSetSystem), &font_files);
GetFontFileNames(FcConfigGetFonts(NULL, FcSetApplication), &font_files);
CHECK_GT(font_files.size(), 0u)
<< "Font configuration doesn't contain any fonts!";
// Get freetype to load every font file we know about. This will cause the
// font files to get cached in memory. Once that's done we shouldn't have to
// access the file system for fonts at all.
FT_Library library;
for (std::set<std::string>::const_iterator iter = font_files.begin();
iter != font_files.end(); ++iter) {
FT_Face face;
CHECK_EQ(0, FT_New_Face(library, iter->c_str(), 0, &face))
<< "Failed to load font face: " << *iter;
FT_Done_FreeType(library); // Cached stuff will stick around... ?
void ReleaseFonts() {
} // namespace headless