usr.bin/gzip/unbzip2.c

   1 /*      $NetBSD: unbzip2.c,v 1.12 2009/10/11 05:17:20 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
  32 /* This file is #included by gzip.c */
  33
  34 static off_t
  35 unbzip2(int in, int out, char *pre, size_t prelen, off_t *bytes_in)
  36 {
  37         int             ret, end_of_file, cold = 0;
  38         off_t           bytes_out = 0;
  39         bz_stream       bzs;
  40         static char     *inbuf, *outbuf;
  41
  42         if (inbuf == NULL)
  43                 inbuf = malloc(BUFLEN);
  44         if (outbuf == NULL)
  45                 outbuf = malloc(BUFLEN);
  46         if (inbuf == NULL || outbuf == NULL)
  47                 maybe_err("malloc");
  48
  49         bzs.bzalloc = NULL;
  50         bzs.bzfree = NULL;
  51         bzs.opaque = NULL;
  52
  53         end_of_file = 0;
  54         ret = BZ2_bzDecompressInit(&bzs, 0, 0);
  55         if (ret != BZ_OK)
  56                 maybe_errx("bzip2 init");
  57
  58         /* Prepend. */
  59         bzs.avail_in = prelen;
  60         bzs.next_in = pre;
  61
  62         if (bytes_in)
  63                 *bytes_in = prelen;
  64
  65         while (ret == BZ_OK) {
  66                 if (bzs.avail_in == 0 && !end_of_file) {
  67                         ssize_t n;
  68
  69                         n = read(in, inbuf, BUFLEN);
  70                         if (n < 0)
  71                                 maybe_err("read");
  72                         if (n == 0)
  73                                 end_of_file = 1;
  74                         bzs.next_in = inbuf;
  75                         bzs.avail_in = n;
  76                         if (bytes_in)
  77                                 *bytes_in += n;
  78                 }
  79
  80                 bzs.next_out = outbuf;
  81                 bzs.avail_out = BUFLEN;
  82                 ret = BZ2_bzDecompress(&bzs);
  83
  84                 switch (ret) {
  85                 case BZ_STREAM_END:
  86                 case BZ_OK:
  87                         if (ret == BZ_OK && end_of_file) {
  88                                 /*
  89                                  * If we hit this after a stream end, consider
  90                                  * it as the end of the whole file and don't
  91                                  * bail out.
  92                                  */
  93                                 if (cold == 1)
  94                                         ret = BZ_STREAM_END;
  95                                 else
  96                                         maybe_errx("truncated file");
  97                         }
  98                         cold = 0;
  99                         if (!tflag && bzs.avail_out != BUFLEN) {
 100                                 ssize_t n;
 101
 102                                 n = write(out, outbuf, BUFLEN - bzs.avail_out);
 103                                 if (n < 0)
 104                                         maybe_err("write");
 105                                 bytes_out += n;
 106                         }
 107                         if (ret == BZ_STREAM_END && !end_of_file) {
 108                                 if (BZ2_bzDecompressEnd(&bzs) != BZ_OK ||
 109                                     BZ2_bzDecompressInit(&bzs, 0, 0) != BZ_OK)
 110                                         maybe_errx("bzip2 re-init");
 111                                 cold = 1;
 112                                 ret = BZ_OK;
 113                         }
 114                         break;
 115
 116                 case BZ_DATA_ERROR:
 117                         maybe_warnx("bzip2 data integrity error");
 118                         break;
 119
 120                 case BZ_DATA_ERROR_MAGIC:
 121                         maybe_warnx("bzip2 magic number error");
 122                         break;
 123
 124                 case BZ_MEM_ERROR:
 125                         maybe_warnx("bzip2 out of memory");
 126                         break;
 127
 128                 default:
 129                         maybe_warnx("unknown bzip2 error: %d", ret);
 130                         break;
 131                 }
 132         }
 133
 134         if (ret != BZ_STREAM_END || BZ2_bzDecompressEnd(&bzs) != BZ_OK)
 135                 return (-1);
 136
 137         return (bytes_out);
 138 }