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/*
* Copyright 2003-2018 The Music Player Daemon Project
* http://www.musicpd.org
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*/
#include "AutoGunzipReader.hxx"
#include "GunzipReader.hxx"
AutoGunzipReader::~AutoGunzipReader()
{
delete gunzip;
}
gcc_pure
static bool
IsGzip(const uint8_t data[4]) noexcept
{
return data[0] == 0x1f && data[1] == 0x8b && data[2] == 0x08 &&
(data[3] & 0xe0) == 0;
}
inline void
AutoGunzipReader::Detect()
{
const uint8_t *data = (const uint8_t *)peek.Peek(4);
if (data == nullptr) {
next = &peek;
return;
}
if (IsGzip(data))
next = gunzip = new GunzipReader(peek);
else
next = &peek;
}
size_t
AutoGunzipReader::Read(void *data, size_t size)
{
if (next == nullptr)
Detect();
assert(next != nullptr);
return next->Read(data, size);
}