src/lib/font_config.cc

   1 /*
   2     Copyright (C) 2014-2023 Carl Hetherington <cth@carlh.net>
   3
   4     This file is part of DCP-o-matic.
   5
   6     DCP-o-matic is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     DCP-o-matic is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 */
  20
  21
  22 #include "dcpomatic_assert.h"
  23 #include "dcpomatic_log.h"
  24 #include "font.h"
  25 #include "font_config.h"
  26 #include "util.h"
  27 #include <fontconfig/fontconfig.h>
  28 #include <boost/filesystem.hpp>
  29 #include <boost/optional.hpp>
  30
  31
  32 using std::shared_ptr;
  33 using std::string;
  34 using boost::optional;
  35
  36
  37 FontConfig* FontConfig::_instance;
  38
  39
  40 FontConfig::FontConfig()
  41 {
  42         _config = FcInitLoadConfigAndFonts();
  43         FcConfigSetCurrent(_config);
  44 }
  45
  46
  47 FontConfig::~FontConfig()
  48 {
  49         for (auto file: _temp_files) {
  50                 boost::system::error_code ec;
  51                 boost::filesystem::remove(file, ec);
  52         }
  53 }
  54
  55
  56 string
  57 FontConfig::make_font_available(shared_ptr<dcpomatic::Font> font)
  58 {
  59         auto existing = _available_fonts.find(font->id());
  60         if (existing != _available_fonts.end()) {
  61                 return existing->second;
  62         }
  63
  64         boost::filesystem::path font_file = default_font_file();
  65         if (font->file()) {
  66                 font_file = *font->file();
  67         } else if (font->data()) {
  68                 /* This font only exists in memory (so far) but FontConfig doesn't have an API to add a font
  69                  * from a memory buffer (AFAICS).
  70                  * https://gitlab.freedesktop.org/fontconfig/fontconfig/-/issues/12
  71                  * As a workaround, write the font data to a temporary file and use that.
  72                  */
  73                 font_file = boost::filesystem::temp_directory_path() / boost::filesystem::unique_path();
  74                 _temp_files.push_back(font_file);
  75                 font->data()->write(font_file);
  76         }
  77
  78
  79         /* Make this font available to DCP-o-matic */
  80         optional<string> font_name;
  81         FcConfigAppFontAddFile (_config, reinterpret_cast<FcChar8 const *>(font_file.string().c_str()));
  82         auto pattern = FcPatternBuild (
  83                 0, FC_FILE, FcTypeString, font_file.string().c_str(), static_cast<char *>(0)
  84                 );
  85         auto object_set = FcObjectSetBuild (FC_FAMILY, FC_STYLE, FC_LANG, FC_FILE, static_cast<char *> (0));
  86         auto font_set = FcFontList (_config, pattern, object_set);
  87         if (font_set) {
  88                 for (int i = 0; i < font_set->nfont; ++i) {
  89                         FcPattern* font = font_set->fonts[i];
  90                         FcChar8* file;
  91                         FcChar8* family;
  92                         FcChar8* style;
  93                         if (
  94                                 FcPatternGetString (font, FC_FILE, 0, &file) == FcResultMatch &&
  95                                 FcPatternGetString (font, FC_FAMILY, 0, &family) == FcResultMatch &&
  96                                 FcPatternGetString (font, FC_STYLE, 0, &style) == FcResultMatch
  97                                 ) {
  98                                 font_name = reinterpret_cast<char const *> (family);
  99                         }
 100                 }
 101
 102                 FcFontSetDestroy (font_set);
 103         }
 104
 105         FcObjectSetDestroy (object_set);
 106         FcPatternDestroy (pattern);
 107
 108         DCPOMATIC_ASSERT(font_name);
 109
 110         _available_fonts[font->id()] = *font_name;
 111
 112         FcConfigBuildFonts(_config);
 113         return *font_name;
 114 }
 115
 116
 117 optional<boost::filesystem::path>
 118 FontConfig::system_font_with_name(string name)
 119 {
 120         optional<boost::filesystem::path> path;
 121
 122         LOG_GENERAL("Searching system for font %1", name);
 123         auto pattern = FcNameParse(reinterpret_cast<FcChar8 const*>(name.c_str()));
 124         auto object_set = FcObjectSetBuild(FC_FILE, nullptr);
 125         auto font_set = FcFontList(_config, pattern, object_set);
 126         if (font_set) {
 127                 LOG_GENERAL("%1 candidate fonts found", font_set->nfont);
 128                 for (int i = 0; i < font_set->nfont; ++i) {
 129                         auto font = font_set->fonts[i];
 130                         FcChar8* file;
 131                         if (FcPatternGetString(font, FC_FILE, 0, &file) == FcResultMatch) {
 132                                 path = boost::filesystem::path(reinterpret_cast<char*>(file));
 133                                 LOG_GENERAL("Found %1", *path);
 134                                 break;
 135                         }
 136                 }
 137                 FcFontSetDestroy(font_set);
 138         } else {
 139                 LOG_GENERAL_NC("No candidate fonts found");
 140         }
 141
 142         FcObjectSetDestroy(object_set);
 143         FcPatternDestroy(pattern);
 144
 145         if (path) {
 146                 LOG_GENERAL("Searched system for font %1, found %2", name, *path);
 147         } else {
 148                 LOG_GENERAL("Searched system for font %1; nothing found", name);
 149         }
 150
 151         return path;
 152 }
 153
 154
 155 FontConfig *
 156 FontConfig::instance()
 157 {
 158         if (!_instance) {
 159                 _instance = new FontConfig();
 160         }
 161
 162         return _instance;
 163 }
 164
 165
 166 void
 167 FontConfig::drop()
 168 {
 169         delete _instance;
 170         _instance = nullptr;
 171 }
 172