Fix subtitle font handling with in-memory fonts from SMPTE (#2509).

[dcpomatic.git] / src / lib / font_config.cc

diff --git a/src/lib/font_config.cc b/src/lib/font_config.cc
index 40b9770c76062069af9ece55c5bd7fe30b7a6d3c..d4a442fc1f84434978b0ec02eaabce5fd6f89bd6 100644 (file)
--- a/src/lib/font_config.cc
+++ b/src/lib/font_config.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2014-2021 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2014-2023 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
@@ -21,12 +21,15 @@
 
 #include "dcpomatic_assert.h"
 #include "dcpomatic_log.h"
+#include "font.h"
 #include "font_config.h"
+#include "util.h"
 #include <fontconfig/fontconfig.h>
 #include <boost/filesystem.hpp>
 #include <boost/optional.hpp>
 
 
+using std::shared_ptr;
 using std::string;
 using boost::optional;
 
@@ -41,14 +44,38 @@ FontConfig::FontConfig()
 }
 
 
+FontConfig::~FontConfig()
+{
+       for (auto file: _temp_files) {
+               boost::system::error_code ec;
+               boost::filesystem::remove(file, ec);
+       }
+}
+
+
 string
-FontConfig::make_font_available(boost::filesystem::path font_file)
+FontConfig::make_font_available(shared_ptr<dcpomatic::Font> font)
 {
-       auto existing = _available_fonts.find(font_file);
+       auto existing = _available_fonts.find(font->id());
        if (existing != _available_fonts.end()) {
                return existing->second;
        }
 
+       boost::filesystem::path font_file = default_font_file();
+       if (font->file()) {
+               font_file = *font->file();
+       } else if (font->data()) {
+               /* This font only exists in memory (so far) but FontConfig doesn't have an API to add a font
+                * from a memory buffer (AFAICS).
+                * https://gitlab.freedesktop.org/fontconfig/fontconfig/-/issues/12
+                * As a workaround, write the font data to a temporary file and use that.
+                */
+               font_file = boost::filesystem::temp_directory_path() / boost::filesystem::unique_path();
+               _temp_files.push_back(font_file);
+               font->data()->write(font_file);
+       }
+
+
        /* Make this font available to DCP-o-matic */
        optional<string> font_name;
        FcConfigAppFontAddFile (_config, reinterpret_cast<FcChar8 const *>(font_file.string().c_str()));
@@ -80,7 +107,7 @@ FontConfig::make_font_available(boost::filesystem::path font_file)
 
        DCPOMATIC_ASSERT(font_name);
 
-       _available_fonts[font_file] = *font_name;
+       _available_fonts[font->id()] = *font_name;
 
        FcConfigBuildFonts(_config);
        return *font_name;
@@ -135,3 +162,11 @@ FontConfig::instance()
        return _instance;
 }
 
+
+void
+FontConfig::drop()
+{
+       delete _instance;
+       _instance = nullptr;
+}
+