GunzipReader.hxx

/*
 * Copyright 2014-2019 Max Kellermann <max.kellermann@gmail.com>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the
 * distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
 * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef GUNZIP_READER_HXX
#define GUNZIP_READER_HXX

#include "Reader.hxx"
#include "util/StaticFifoBuffer.hxx"

#include <zlib.h>

/**
 * A filter that decompresses data using zlib.
 */
class GunzipReader final : public Reader {
	Reader &next;

	bool eof = false;

	z_stream z;

	StaticFifoBuffer<Bytef, 65536> buffer;

public:
	/**
	 * Construct the filter.
	 *
	 * Throws on error.
	 */
	explicit GunzipReader(Reader &_next);

	~GunzipReader() noexcept {
		inflateEnd(&z);
	}

	/* virtual methods from class Reader */
	size_t Read(void *data, size_t size) override;

private:
	bool FillBuffer();
};

#endif