usr/src/uts/common/fs/zfs/gzip.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <sys/debug.h>
  30 #include <sys/types.h>
  31 #include <sys/zmod.h>
  32
  33 #ifdef _KERNEL
  34 #include <sys/systm.h>
  35 #else
  36 #include <strings.h>
  37 #endif
  38
  39 size_t
  40 gzip_compress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n)
  41 {
  42         size_t dstlen = d_len;
  43
  44         ASSERT(d_len <= s_len);
  45
  46         if (z_compress_level(d_start, &dstlen, s_start, s_len, n) != Z_OK) {
  47                 if (d_len != s_len)
  48                         return (s_len);
  49
  50                 bcopy(s_start, d_start, s_len);
  51                 return (s_len);
  52         }
  53
  54         return (dstlen);
  55 }
  56
  57 /*ARGSUSED*/
  58 int
  59 gzip_decompress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n)
  60 {
  61         size_t dstlen = d_len;
  62
  63         ASSERT(d_len >= s_len);
  64
  65         if (z_uncompress(d_start, &dstlen, s_start, s_len) != Z_OK)
  66                 return (-1);
  67
  68         return (0);
  69 }