path: root/archived/projt-launcher/launcher/GZip.cpp

// SPDX-License-Identifier: GPL-3.0-only
// SPDX-FileCopyrightText: 2026 Project Tick
// SPDX-FileContributor: Project Tick Team
/*
 *  ProjT Launcher - Minecraft Launcher
 *  Copyright (C) 2026 Project Tick
 *
 *  This program 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, version 3.
 *
 *  This program 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 this program.  If not, write to the Free Software Foundation,
 *  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
/* === Upstream License Block (Do Not Modify) ==============================
 *
 *  Prism Launcher - Minecraft Launcher
 *  Copyright (C) 2022 Sefa Eyeoglu <contact@scrumplex.net>
 *
 *  This program 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, version 3.
 *
 *  This program 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 this program.  If not, write to the Free Software Foundation,
 *  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * This file incorporates work covered by the following copyright and
 * permission notice:
 *
 *      Copyright 2013-2021 MultiMC Contributors
 *
 *      Licensed under the Apache License, Version 2.0 (the "License");
 *      you may not use this file except in compliance with the License.
 *      You may obtain a copy of the License at
 *
 *          http://www.apache.org/licenses/LICENSE-2.0
 *
 *      Unless required by applicable law or agreed to in writing, software
 *      distributed under the License is distributed on an "AS IS" BASIS,
 *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *      See the License for the specific language governing permissions and
 *      limitations under the License.
 *
   ======================================================================== */
#include "GZip.h"
#include <ptlibzippy.h>
#include <QByteArray>
#include <QDebug>
#include <QFile>

bool GZip::unzip(const QByteArray& compressedBytes, QByteArray& uncompressedBytes)
{
	if (compressedBytes.size() == 0)
	{
		uncompressedBytes = compressedBytes;
		return true;
	}

	unsigned uncompLength = compressedBytes.size();
	uncompressedBytes.clear();
	uncompressedBytes.resize(uncompLength);

	z_stream strm;
	memset(&strm, 0, sizeof(strm));
	strm.next_in  = (Bytef*)compressedBytes.data();
	strm.avail_in = compressedBytes.size();

	bool done = false;

	if (inflateInit2(&strm, (16 + MAX_WBITS)) != Z_OK)
	{
		return false;
	}

	int err = Z_OK;

	while (!done)
	{
		// If our output buffer is too small
		if (strm.total_out >= uncompLength)
		{
			uncompressedBytes.resize(uncompLength * 2);
			uncompLength *= 2;
		}

		strm.next_out  = reinterpret_cast<Bytef*>((uncompressedBytes.data() + strm.total_out));
		strm.avail_out = uncompLength - strm.total_out;

		// Inflate another chunk.
		err = inflate(&strm, Z_SYNC_FLUSH);
		if (err == Z_STREAM_END)
			done = true;
		else if (err != Z_OK)
		{
			break;
		}
	}

	if (inflateEnd(&strm) != Z_OK || !done)
	{
		return false;
	}

	uncompressedBytes.resize(strm.total_out);
	return true;
}

bool GZip::zip(const QByteArray& uncompressedBytes, QByteArray& compressedBytes)
{
	if (uncompressedBytes.size() == 0)
	{
		compressedBytes = uncompressedBytes;
		return true;
	}

	unsigned compLength = qMin(uncompressedBytes.size(), 16);
	compressedBytes.clear();
	compressedBytes.resize(compLength);

	z_stream zs;
	memset(&zs, 0, sizeof(zs));

	if (deflateInit2(&zs, Z_DEFAULT_COMPRESSION, Z_DEFLATED, (16 + MAX_WBITS), 8, Z_DEFAULT_STRATEGY) != Z_OK)
	{
		return false;
	}

	zs.next_in	= (Bytef*)uncompressedBytes.data();
	zs.avail_in = uncompressedBytes.size();

	int ret;
	compressedBytes.resize(uncompressedBytes.size());

	unsigned offset = 0;
	unsigned temp	= 0;
	do
	{
		auto remaining = compressedBytes.size() - offset;
		if (remaining < 1)
		{
			compressedBytes.resize(compressedBytes.size() * 2);
		}
		zs.next_out = reinterpret_cast<Bytef*>((compressedBytes.data() + offset));
		temp = zs.avail_out = compressedBytes.size() - offset;
		ret					= deflate(&zs, Z_FINISH);
		offset += temp - zs.avail_out;
	}
	while (ret == Z_OK);

	compressedBytes.resize(offset);

	if (deflateEnd(&zs) != Z_OK)
	{
		return false;
	}

	if (ret != Z_STREAM_END)
	{
		return false;
	}
	return true;
}

int inf(QFile* source, std::function<bool(const QByteArray&)> handleBlock)
{
	constexpr auto CHUNK = 16384;
	int ret;
	unsigned have;
	z_stream strm;
	memset(&strm, 0, sizeof(strm));
	char in[CHUNK];
	unsigned char out[CHUNK];

	ret = inflateInit2(&strm, (16 + MAX_WBITS));
	if (ret != Z_OK)
		return ret;

	/* decompress until deflate stream ends or end of file */
	do
	{
		strm.avail_in = source->read(in, CHUNK);
		if (source->error())
		{
			(void)inflateEnd(&strm);
			return Z_ERRNO;
		}
		if (strm.avail_in == 0)
			break;
		strm.next_in = reinterpret_cast<Bytef*>(in);

		/* run inflate() on input until output buffer not full */
		do
		{
			strm.avail_out = CHUNK;
			strm.next_out  = out;
			ret			   = inflate(&strm, Z_NO_FLUSH);
			assert(ret != Z_STREAM_ERROR); /* state not clobbered */
			switch (ret)
			{
				case Z_NEED_DICT:
					ret = Z_DATA_ERROR;
					[[fallthrough]];
				case Z_DATA_ERROR:
				case Z_MEM_ERROR: (void)inflateEnd(&strm); return ret;
			}
			have = CHUNK - strm.avail_out;
			if (!handleBlock(QByteArray(reinterpret_cast<const char*>(out), have)))
			{
				(void)inflateEnd(&strm);
				return Z_OK;
			}
		}
		while (strm.avail_out == 0);

		/* done when inflate() says it's done */
	}
	while (ret != Z_STREAM_END);

	/* clean up and return */
	(void)inflateEnd(&strm);
	return ret == Z_STREAM_END ? Z_OK : Z_DATA_ERROR;
}

QString zerr(int ret)
{
	switch (ret)
	{
		case Z_ERRNO: return QObject::tr("error handling file");
		case Z_STREAM_ERROR: return QObject::tr("invalid compression level");
		case Z_DATA_ERROR: return QObject::tr("invalid or incomplete deflate data");
		case Z_MEM_ERROR: return QObject::tr("out of memory");
		case Z_VERSION_ERROR: return QObject::tr("zlib version mismatch!");
	}
	return {};
}

QString GZip::readGzFileByBlocks(QFile* source, std::function<bool(const QByteArray&)> handleBlock)
{
	auto ret = inf(source, handleBlock);
	return zerr(ret);
}