Add Unzipper.

1 files changed, 89 insertions, 0 deletions

diff --git a/src/lib/unzipper.cc b/src/lib/unzipper.cc
new file mode 100644
index 000000000..2add8f2a9
--- /dev/null
+++ b/src/lib/unzipper.cc
@@ -0,0 +1,89 @@
+/*
+    Copyright (C) 2024 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic 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.
+
+    DCP-o-matic 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 DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#include "dcpomatic_assert.h"
+#include "exceptions.h"
+#include "unzipper.h"
+#include <dcp/filesystem.h>
+#include <dcp/scope_guard.h>
+#include <zip.h>
+#include <boost/filesystem.hpp>
+#include <stdexcept>
+
+#include "i18n.h"
+
+
+using std::runtime_error;
+using std::shared_ptr;
+using std::string;
+
+
+Unzipper::Unzipper(boost::filesystem::path file)
+{
+	int error;
+	_zip = zip_open(dcp::filesystem::fix_long_path(file).string().c_str(), ZIP_RDONLY, &error);
+	if (!_zip) {
+		throw FileError("could not open ZIP file", file);
+	}
+}
+
+
+Unzipper::~Unzipper()
+{
+	zip_close(_zip);
+}
+
+
+string
+Unzipper::get(string const& filename)
+{
+	auto file = zip_fopen(_zip, filename.c_str(), 0);
+	if (!file) {
+		throw runtime_error(String::compose(_("Could not find file %1 in ZIP file"), filename));
+	}
+
+	dcp::ScopeGuard sg = [file]() { zip_fclose(file); };
+
+	int constexpr maximum = 65536;
+
+	dcp::ArrayData data(maximum);
+	int remaining = maximum;
+	uint8_t* next = data.data();
+
+	while (remaining > 0) {
+		auto read = zip_fread(file, next, remaining);
+		if (read == 0) {
+			break;
+		} else if (read == -1) {
+			throw runtime_error("Could not read from ZIP file");
+		}
+
+		next += read;
+		remaining -= read;
+	}
+
+	if (remaining == 0) {
+		throw runtime_error("File from ZIP is too big");
+	}
+
+	return string(reinterpret_cast<char*>(data.data()), maximum - remaining);
+}
+