usr.bin/gzip/unbzip2.c

   1 /*      $NetBSD: unbzip2.c,v 1.13 2009/12/05 03:23:37 mrg Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2006 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Simon Burge.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  *
  31  * $FreeBSD$
  32  */
  33
  34 /* This file is #included by gzip.c */
  35
  36 static off_t
  37 unbzip2(int in, int out, char *pre, size_t prelen, off_t *bytes_in)
  38 {
  39         int             ret, end_of_file, cold = 0;
  40         off_t           bytes_out = 0;
  41         bz_stream       bzs;
  42         static char     *inbuf, *outbuf;
  43
  44         if (inbuf == NULL)
  45                 inbuf = malloc(BUFLEN);
  46         if (outbuf == NULL)
  47                 outbuf = malloc(BUFLEN);
  48         if (inbuf == NULL || outbuf == NULL)
  49                 maybe_err("malloc");
  50
  51         bzs.bzalloc = NULL;
  52         bzs.bzfree = NULL;
  53         bzs.opaque = NULL;
  54
  55         end_of_file = 0;
  56         ret = BZ2_bzDecompressInit(&bzs, 0, 0);
  57         if (ret != BZ_OK)
  58                 maybe_errx("bzip2 init");
  59
  60         /* Prepend. */
  61         bzs.avail_in = prelen;
  62         bzs.next_in = pre;
  63
  64         if (bytes_in)
  65                 *bytes_in = prelen;
  66
  67         while (ret == BZ_OK) {
  68                 if (bzs.avail_in == 0 && !end_of_file) {
  69                         ssize_t n;
  70
  71                         n = read(in, inbuf, BUFLEN);
  72                         if (n < 0)
  73                                 maybe_err("read");
  74                         if (n == 0)
  75                                 end_of_file = 1;
  76                         bzs.next_in = inbuf;
  77                         bzs.avail_in = n;
  78                         if (bytes_in)
  79                                 *bytes_in += n;
  80                 }
  81
  82                 bzs.next_out = outbuf;
  83                 bzs.avail_out = BUFLEN;
  84                 ret = BZ2_bzDecompress(&bzs);
  85
  86                 switch (ret) {
  87                 case BZ_STREAM_END:
  88                 case BZ_OK:
  89                         if (ret == BZ_OK && end_of_file) {
  90                                 /*
  91                                  * If we hit this after a stream end, consider
  92                                  * it as the end of the whole file and don't
  93                                  * bail out.
  94                                  */
  95                                 if (cold == 1)
  96                                         ret = BZ_STREAM_END;
  97                                 else
  98                                         maybe_errx("truncated file");
  99                         }
 100                         cold = 0;
 101                         if (!tflag && bzs.avail_out != BUFLEN) {
 102                                 ssize_t n;
 103
 104                                 n = write(out, outbuf, BUFLEN - bzs.avail_out);
 105                                 if (n < 0)
 106                                         maybe_err("write");
 107                                 bytes_out += n;
 108                         }
 109                         if (ret == BZ_STREAM_END && !end_of_file) {
 110                                 if (BZ2_bzDecompressEnd(&bzs) != BZ_OK ||
 111                                     BZ2_bzDecompressInit(&bzs, 0, 0) != BZ_OK)
 112                                         maybe_errx("bzip2 re-init");
 113                                 cold = 1;
 114                                 ret = BZ_OK;
 115                         }
 116                         break;
 117
 118                 case BZ_DATA_ERROR:
 119                         maybe_warnx("bzip2 data integrity error");
 120                         break;
 121
 122                 case BZ_DATA_ERROR_MAGIC:
 123                         maybe_warnx("bzip2 magic number error");
 124                         break;
 125
 126                 case BZ_MEM_ERROR:
 127                         maybe_warnx("bzip2 out of memory");
 128                         break;
 129
 130                 default:
 131                         maybe_warnx("unknown bzip2 error: %d", ret);
 132                         break;
 133                 }
 134         }
 135
 136         if (ret != BZ_STREAM_END || BZ2_bzDecompressEnd(&bzs) != BZ_OK)
 137                 return (-1);
 138
 139         return (bytes_out);
 140 }
 141