ntfs_compr.c revision 47060
1292309Srrs/* $NetBSD: ntfs_compr.c,v 1.2 1999/05/06 15:43:18 christos Exp $ */ 2292309Srrs 3292309Srrs/*- 4292309Srrs * Copyright (c) 1998, 1999 Semen Ustimenko 5292309Srrs * All rights reserved. 6292309Srrs * 7292309Srrs * Redistribution and use in source and binary forms, with or without 8292309Srrs * modification, are permitted provided that the following conditions 9292309Srrs * are met: 10292309Srrs * 1. Redistributions of source code must retain the above copyright 11292309Srrs * notice, this list of conditions and the following disclaimer. 12292309Srrs * 2. Redistributions in binary form must reproduce the above copyright 13292309Srrs * notice, this list of conditions and the following disclaimer in the 14292309Srrs * documentation and/or other materials provided with the distribution. 15292309Srrs * 16292309Srrs * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17292309Srrs * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18292309Srrs * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19292309Srrs * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20292309Srrs * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21292309Srrs * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22292309Srrs * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23292309Srrs * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24292309Srrs * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25292309Srrs * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26292309Srrs * SUCH DAMAGE. 27292309Srrs * 28292309Srrs * $Id: ntfs_compr.c,v 1.3 1999/04/20 21:06:43 semenu Exp $ 29292309Srrs */ 30292309Srrs 31292309Srrs#include <sys/param.h> 32292309Srrs#include <sys/systm.h> 33292309Srrs#include <sys/namei.h> 34292309Srrs#include <sys/proc.h> 35292309Srrs#include <sys/kernel.h> 36292309Srrs#include <sys/vnode.h> 37292309Srrs#include <sys/mount.h> 38292309Srrs#include <sys/buf.h> 39292309Srrs#include <sys/file.h> 40292309Srrs#include <sys/malloc.h> 41292309Srrs#ifdef __FreeBSD__ 42292309Srrs#include <machine/clock.h> 43292309Srrs#endif 44292309Srrs 45292309Srrs#include <miscfs/specfs/specdev.h> 46292309Srrs 47292309Srrs#include <ntfs/ntfs.h> 48292309Srrs#include <ntfs/ntfs_compr.h> 49292309Srrs 50292309Srrs#define GET_UINT16(addr) (*((u_int16_t *)(addr))) 51292309Srrs 52292309Srrsint 53292309Srrsntfs_uncompblock( 54292309Srrs u_int8_t * buf, 55292309Srrs u_int8_t * cbuf) 56292309Srrs{ 57292309Srrs u_int32_t ctag; 58292309Srrs int len, dshift, lmask; 59292309Srrs int blen, boff; 60292309Srrs int i, j; 61292309Srrs int pos, cpos; 62292309Srrs 63292309Srrs len = GET_UINT16(cbuf) & 0xFFF; 64292309Srrs dprintf(("ntfs_uncompblock: block length: %d + 3, 0x%x,0x%04x\n", 65292309Srrs len, len, GET_UINT16(cbuf))); 66292309Srrs 67292309Srrs if (!(GET_UINT16(cbuf) & 0x8000)) { 68292309Srrs if ((len + 1) != NTFS_COMPBLOCK_SIZE) { 69292309Srrs dprintf(("ntfs_uncompblock: len: %x instead of %d\n", 70292309Srrs len, 0xfff)); 71292309Srrs } 72292309Srrs memcpy(buf, cbuf + 2, len + 1); 73292309Srrs bzero(buf + len + 1, NTFS_COMPBLOCK_SIZE - 1 - len); 74292309Srrs return len + 3; 75292309Srrs } 76292309Srrs cpos = 2; 77292309Srrs pos = 0; 78292309Srrs while ((cpos < len + 3) && (pos < NTFS_COMPBLOCK_SIZE)) { 79292309Srrs ctag = cbuf[cpos++]; 80292309Srrs for (i = 0; (i < 8) && (pos < NTFS_COMPBLOCK_SIZE); i++) { 81292309Srrs if (ctag & 1) { 82292309Srrs for (j = pos - 1, lmask = 0xFFF, dshift = 12; 83292309Srrs j >= 0x10; j >>= 1) { 84292309Srrs dshift--; 85292309Srrs lmask >>= 1; 86292309Srrs } 87292309Srrs boff = -1 - (GET_UINT16(cbuf + cpos) >> dshift); 88292309Srrs blen = 3 + (GET_UINT16(cbuf + cpos) & lmask); 89292309Srrs for (j = 0; (j < blen) && (pos < NTFS_COMPBLOCK_SIZE); j++) { 90292309Srrs buf[pos] = buf[pos + boff]; 91292309Srrs pos++; 92292309Srrs } 93292309Srrs cpos += 2; 94292309Srrs } else { 95292309Srrs buf[pos++] = cbuf[cpos++]; 96292309Srrs } 97292309Srrs ctag >>= 1; 98292309Srrs } 99294535Sglebius } 100292309Srrs return len + 3; 101292309Srrs} 102292309Srrs 103292309Srrsint 104292309Srrsntfs_uncompunit( 105292309Srrs struct ntfsmount * ntmp, 106292309Srrs u_int8_t * uup, 107294931Sglebius u_int8_t * cup) 108292309Srrs{ 109292309Srrs int i; 110292309Srrs int off = 0; 111292309Srrs int new; 112292309Srrs 113292309Srrs for (i = 0; i * NTFS_COMPBLOCK_SIZE < ntfs_cntob(NTFS_COMPUNIT_CL); i++) { 114292309Srrs new = ntfs_uncompblock(uup + i * NTFS_COMPBLOCK_SIZE, cup + off); 115292309Srrs if (new == 0) 116292309Srrs return (EINVAL); 117292309Srrs off += new; 118292309Srrs } 119292309Srrs return (0); 120292309Srrs} 121292309Srrs