NetBSD/usr.bin/gzip/unxz.c

161 lines
4.7 KiB
C

/* $NetBSD: unxz.c,v 1.5 2011/09/30 01:32:21 christos Exp $ */
/*-
* Copyright (c) 2011 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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.
*/
#include <sys/cdefs.h>
__RCSID("$NetBSD: unxz.c,v 1.5 2011/09/30 01:32:21 christos Exp $");
#include <stdarg.h>
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <lzma.h>
static off_t
unxz(int i, int o, char *pre, size_t prelen, off_t *bytes_in)
{
lzma_stream strm = LZMA_STREAM_INIT;
static const int flags = LZMA_TELL_UNSUPPORTED_CHECK|LZMA_CONCATENATED;
lzma_ret ret;
lzma_action action = LZMA_RUN;
off_t bytes_out, bp;
uint8_t ibuf[BUFSIZ];
uint8_t obuf[BUFSIZ];
if (bytes_in == NULL)
bytes_in = &bp;
strm.next_in = ibuf;
memcpy(ibuf, pre, prelen);
strm.avail_in = read(i, ibuf + prelen, sizeof(ibuf) - prelen);
if (strm.avail_in == (size_t)-1)
maybe_err("read failed");
strm.avail_in += prelen;
*bytes_in = strm.avail_in;
if ((ret = lzma_stream_decoder(&strm, UINT64_MAX, flags)) != LZMA_OK)
maybe_errx("Can't initialize decoder (%d)", ret);
strm.next_out = NULL;
strm.avail_out = 0;
if ((ret = lzma_code(&strm, LZMA_RUN)) != LZMA_OK)
maybe_errx("Can't read headers (%d)", ret);
bytes_out = 0;
strm.next_out = obuf;
strm.avail_out = sizeof(obuf);
for (;;) {
if (strm.avail_in == 0) {
strm.next_in = ibuf;
strm.avail_in = read(i, ibuf, sizeof(ibuf));
switch (strm.avail_in) {
case (size_t)-1:
maybe_err("read failed");
/*NOTREACHED*/
case 0:
action = LZMA_FINISH;
break;
default:
*bytes_in += strm.avail_in;
break;
}
}
ret = lzma_code(&strm, action);
// Write and check write error before checking decoder error.
// This way as much data as possible gets written to output
// even if decoder detected an error.
if (strm.avail_out == 0 || ret != LZMA_OK) {
const size_t write_size = sizeof(obuf) - strm.avail_out;
if (write(o, obuf, write_size) != (ssize_t)write_size)
maybe_err("write failed");
strm.next_out = obuf;
strm.avail_out = sizeof(obuf);
bytes_out += write_size;
}
if (ret != LZMA_OK) {
if (ret == LZMA_STREAM_END) {
// Check that there's no trailing garbage.
if (strm.avail_in != 0 || read(i, ibuf, 1))
ret = LZMA_DATA_ERROR;
else {
lzma_end(&strm);
return bytes_out;
}
}
const char *msg;
switch (ret) {
case LZMA_MEM_ERROR:
msg = strerror(ENOMEM);
break;
case LZMA_FORMAT_ERROR:
msg = "File format not recognized";
break;
case LZMA_OPTIONS_ERROR:
// FIXME: Better message?
msg = "Unsupported compression options";
break;
case LZMA_DATA_ERROR:
msg = "File is corrupt";
break;
case LZMA_BUF_ERROR:
msg = "Unexpected end of input";
break;
case LZMA_MEMLIMIT_ERROR:
msg = "Reached memory limit";
break;
default:
maybe_errx("Unknown error (%d)", ret);
break;
}
maybe_errx("%s", msg);
}
}
}