1 /* 2 * GRUB -- GRand Unified Bootloader 3 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc. 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18 */ 19 /* 20 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 21 * Use is subject to license terms. 22 */ 23 24 #pragma ident "%Z%%M% %I% %E% SMI" 25 26 #include "fsys_zfs.h" 27 28 #define MATCH_BITS 6 29 #define MATCH_MIN 3 30 #define OFFSET_MASK ((1 << (16 - MATCH_BITS)) - 1) 31 32 33 /*ARGSUSED*/ 34 int 35 lzjb_decompress(void *s_start, void *d_start, size_t s_len, size_t d_len) 36 { 37 uchar_t *src = s_start; 38 uchar_t *dst = d_start; 39 uchar_t *d_end = (uchar_t *)d_start + d_len; 40 uchar_t *cpy, copymap; 41 int copymask = 1 << (NBBY - 1); 42 43 while (dst < d_end) { 44 if ((copymask <<= 1) == (1 << NBBY)) { 45 copymask = 1; 46 copymap = *src++; 47 } 48 if (copymap & copymask) { 49 int mlen = (src[0] >> (NBBY - MATCH_BITS)) + MATCH_MIN; 50 int offset = ((src[0] << NBBY) | src[1]) & OFFSET_MASK; 51 src += 2; 52 if ((cpy = dst - offset) < (uchar_t *)d_start) 53 return (-1); 54 while (--mlen >= 0 && dst < d_end) 55 *dst++ = *cpy++; 56 } else { 57 *dst++ = *src++; 58 } 59 } 60 return (0); 61 } 62