Add dcp::combine().

1 files changed, 165 insertions, 0 deletions

diff --git a/src/combine.cc b/src/combine.cc
new file mode 100644
index 00000000..0e262fce
--- /dev/null
+++ b/src/combine.cc
@@ -0,0 +1,165 @@
+/*
+    Copyright (C) 2020 Carl Hetherington <cth@carlh.net>
+
+    This file is part of libdcp.
+
+    libdcp is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    libdcp is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with libdcp.  If not, see <http://www.gnu.org/licenses/>.
+
+    In addition, as a special exception, the copyright holders give
+    permission to link the code of portions of this program with the
+    OpenSSL library under certain conditions as described in each
+    individual source file, and distribute linked combinations
+    including the two.
+
+    You must obey the GNU General Public License in all respects
+    for all of the code used other than OpenSSL.  If you modify
+    file(s) with this exception, you may extend this exception to your
+    version of the file(s), but you are not obligated to do so.  If you
+    do not wish to do so, delete this exception statement from your
+    version.  If you delete this exception statement from all source
+    files in the program, then also delete it here.
+*/
+
+
+#include "asset.h"
+#include "combine.h"
+#include "cpl.h"
+#include "dcp.h"
+#include "dcp_assert.h"
+#include "exceptions.h"
+#include "font_asset.h"
+#include "interop_subtitle_asset.h"
+#include "raw_convert.h"
+#include <boost/filesystem.hpp>
+#include <boost/foreach.hpp>
+#include <set>
+#include <string>
+#include <vector>
+
+
+using std::list;
+using std::map;
+using std::set;
+using std::string;
+using std::vector;
+using boost::dynamic_pointer_cast;
+using boost::optional;
+using boost::shared_ptr;
+
+
+boost::filesystem::path
+make_unique (boost::filesystem::path path)
+{
+	if (!boost::filesystem::exists(path)) {
+		return path;
+	}
+
+	for (int i = 0; i < 10000; ++i) {
+		boost::filesystem::path p = path.parent_path() / (path.stem().string() + dcp::raw_convert<string>(i) + path.extension().string());
+		if (!boost::filesystem::exists(p)) {
+			return p;
+		}
+	}
+
+	DCP_ASSERT (false);
+	return path;
+}
+
+
+static
+void
+create_hard_link_or_copy (boost::filesystem::path from, boost::filesystem::path to)
+{
+	try {
+		create_hard_link (from, to);
+	} catch (boost::filesystem::filesystem_error& e) {
+		if (e.code() == boost::system::errc::cross_device_link) {
+			copy_file (from, to);
+		} else {
+			throw;
+		}
+	}
+}
+
+
+void
+dcp::combine (vector<boost::filesystem::path> inputs, boost::filesystem::path output, shared_ptr<const CertificateChain> signer)
+{
+	using namespace boost::filesystem;
+
+	DCP_ASSERT (!inputs.empty());
+
+	DCP output_dcp (output);
+	optional<dcp::Standard> standard;
+
+	BOOST_FOREACH (path i, inputs) {
+		DCP dcp (i);
+		dcp.read ();
+		if (!standard) {
+			standard = *dcp.standard();
+		} else if (standard != dcp.standard()) {
+			throw CombineError ("Cannot combine Interop and SMPTE DCPs.");
+		}
+	}
+
+	list<path> paths;
+	list<shared_ptr<dcp::Asset> > assets;
+
+	BOOST_FOREACH (path i, inputs) {
+		DCP dcp (i);
+		dcp.read ();
+
+		BOOST_FOREACH (shared_ptr<dcp::CPL> j, dcp.cpls()) {
+			output_dcp.add (j);
+		}
+
+		BOOST_FOREACH (shared_ptr<dcp::Asset> j, dcp.assets(true)) {
+			if (dynamic_pointer_cast<dcp::CPL>(j)) {
+				continue;
+			}
+
+			optional<path> file = j->file();
+			DCP_ASSERT (file);
+			path new_path = make_unique(output / file->filename());
+
+			shared_ptr<dcp::InteropSubtitleAsset> sub = dynamic_pointer_cast<dcp::InteropSubtitleAsset>(j);
+			if (sub) {
+				/* Interop fonts are really fiddly.  The font files are assets (in the ASSETMAP)
+				 * and also linked from the font XML by filename.  We have to fix both these things,
+				 * and re-write the font XML file since the font URI might have changed if it's a duplicate
+				 * with another DCP.
+				 */
+				map<string, path> fonts = sub->font_filenames ();
+				for (map<string, path>::const_iterator k = fonts.begin(); k != fonts.end(); ++k) {
+					sub->set_font_file (k->first, make_unique(output / k->second.filename()));
+				}
+				sub->write (new_path);
+			} else if (!dynamic_pointer_cast<dcp::FontAsset>(j)) {
+				/* Take care of everything else that's not a Interop subtitle asset, Interop font file
+				 * or CPL.
+				 */
+				optional<path> file = j->file();
+				DCP_ASSERT (file);
+				path new_path = make_unique(output / file->filename());
+				create_hard_link_or_copy (*file, new_path);
+				j->set_file (new_path);
+			}
+
+			assets.push_back (j);
+		}
+	}
+
+	output_dcp.resolve_refs (assets);
+	output_dcp.write_xml (*standard, dcp::XMLMetadata(), signer);
+}