/* $OpenBSD: ntfs_compr.c,v 1.7 2013/11/24 16:02:30 jsing Exp $ */ /* $NetBSD: ntfs_compr.c,v 1.1 2002/12/23 17:38:31 jdolecek Exp $ */ /*- * Copyright (c) 1998, 1999 Semen Ustimenko * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * Id: ntfs_compr.c,v 1.4 1999/05/12 09:42:54 semenu Exp */ #include <sys/param.h> #include <sys/systm.h> #include <sys/mount.h> #include <ntfs/ntfs.h> #include <ntfs/ntfs_compr.h> #define GET_UINT16(addr) (*((u_int16_t *)(addr))) int ntfs_uncompblock(u_int8_t *buf, u_int8_t *cbuf) { u_int32_t ctag; int len, dshift, lmask; int blen, boff; int i, j; int pos, cpos; len = GET_UINT16(cbuf) & 0xFFF; DPRINTF("ntfs_uncompblock: block length: %d + 3, 0x%x,0x%04x\n", len, len, GET_UINT16(cbuf)); if (!(GET_UINT16(cbuf) & 0x8000)) { if ((len + 1) != NTFS_COMPBLOCK_SIZE) { DPRINTF("ntfs_uncompblock: len: %x instead of %d\n", len, 0xfff); } memcpy(buf, cbuf + 2, len + 1); bzero(buf + len + 1, NTFS_COMPBLOCK_SIZE - 1 - len); return (len + 3); } cpos = 2; pos = 0; while ((cpos < len + 3) && (pos < NTFS_COMPBLOCK_SIZE)) { ctag = cbuf[cpos++]; for (i = 0; (i < 8) && (pos < NTFS_COMPBLOCK_SIZE); i++) { if (ctag & 1) { for (j = pos - 1, lmask = 0xFFF, dshift = 12; j >= 0x10; j >>= 1) { dshift--; lmask >>= 1; } boff = -1 - (GET_UINT16(cbuf + cpos) >> dshift); blen = 3 + (GET_UINT16(cbuf + cpos) & lmask); for (j = 0; (j < blen) && (pos < NTFS_COMPBLOCK_SIZE); j++) { buf[pos] = buf[pos + boff]; pos++; } cpos += 2; } else { buf[pos++] = cbuf[cpos++]; } ctag >>= 1; } } return (len + 3); } int ntfs_uncompunit(struct ntfsmount *ntmp, u_int8_t *uup, u_int8_t *cup) { int i; int off = 0; int new; for (i = 0; i * NTFS_COMPBLOCK_SIZE < ntfs_cntob(NTFS_COMPUNIT_CL); i++) { new = ntfs_uncompblock(uup + i * NTFS_COMPBLOCK_SIZE, cup + off); if (new == 0) return (EINVAL); off += new; } return (0); }