Markus F.X.J. Oberhumer
189 lines
4.0 KiB
C
189 lines
4.0 KiB
C
/* sw.h -- swaptrick filter
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This file is part of the UPX executable compressor.
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Copyright (C) 1996-2006 Markus Franz Xaver Johannes Oberhumer
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Copyright (C) 1996-2006 Laszlo Molnar
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All Rights Reserved.
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UPX and the UCL library are free software; you can redistribute them
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and/or modify them under the terms of the GNU General Public License as
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published by the Free Software Foundation; either version 2 of
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the License, or (at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; see the file COPYING.
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If not, write to the Free Software Foundation, Inc.,
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59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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Markus F.X.J. Oberhumer Laszlo Molnar
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<mfx@users.sourceforge.net> <ml1050@users.sourceforge.net>
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*/
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/*************************************************************************
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// 16-bit swaptrick ("naive")
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**************************************************************************/
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#define SW16(f, cond, get, set) \
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upx_byte *b = f->buf; \
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upx_byte *b_end = b + f->buf_len - 3; \
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do { \
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if (cond) \
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{ \
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b += 1; \
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unsigned a = (unsigned) (b - f->buf); \
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f->lastcall = a; \
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set(b, get(b)); \
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f->calls++; \
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b += 2 - 1; \
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} \
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} while (++b < b_end); \
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if (f->lastcall) f->lastcall += 2; \
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return 0;
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// filter
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static int f_sw16_e8(Filter *f)
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{
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SW16(f, (*b == 0xe8), get_le16, set_be16)
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}
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static int f_sw16_e9(Filter *f)
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{
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SW16(f, (*b == 0xe9), get_le16, set_be16)
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}
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static int f_sw16_e8e9(Filter *f)
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{
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SW16(f, (*b == 0xe8 || *b == 0xe9), get_le16, set_be16)
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}
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// unfilter
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static int u_sw16_e8(Filter *f)
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{
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SW16(f, (*b == 0xe8), get_be16, set_le16)
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}
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static int u_sw16_e9(Filter *f)
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{
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SW16(f, (*b == 0xe9), get_be16, set_le16)
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}
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static int u_sw16_e8e9(Filter *f)
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{
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SW16(f, (*b == 0xe8 || *b == 0xe9), get_be16, set_le16)
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}
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// scan
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static int s_sw16_e8(Filter *f)
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{
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SW16(f, (*b == 0xe8), get_le16, set_dummy)
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}
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static int s_sw16_e9(Filter *f)
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{
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SW16(f, (*b == 0xe9), get_le16, set_dummy)
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}
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static int s_sw16_e8e9(Filter *f)
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{
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SW16(f, (*b == 0xe8 || *b == 0xe9), get_le16, set_dummy)
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}
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#undef SW16
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/*************************************************************************
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// 32-bit swaptrick ("naive")
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**************************************************************************/
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#define SW32(f, cond, get, set) \
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upx_byte *b = f->buf; \
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upx_byte *b_end = b + f->buf_len - 5; \
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do { \
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if (cond) \
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{ \
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b += 1; \
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unsigned a = (unsigned) (b - f->buf); \
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f->lastcall = a; \
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set(b, get(b)); \
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f->calls++; \
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b += 4 - 1; \
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} \
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} while (++b < b_end); \
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if (f->lastcall) f->lastcall += 4; \
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return 0;
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// filter
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static int f_sw32_e8(Filter *f)
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{
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SW32(f, (*b == 0xe8), get_le32, set_be32)
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}
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static int f_sw32_e9(Filter *f)
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{
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SW32(f, (*b == 0xe9), get_le32, set_be32)
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}
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static int f_sw32_e8e9(Filter *f)
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{
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SW32(f, (*b == 0xe8 || *b == 0xe9), get_le32, set_be32)
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}
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// unfilter
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static int u_sw32_e8(Filter *f)
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{
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SW32(f, (*b == 0xe8), get_be32, set_le32)
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}
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static int u_sw32_e9(Filter *f)
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{
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SW32(f, (*b == 0xe9), get_be32, set_le32)
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}
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static int u_sw32_e8e9(Filter *f)
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{
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SW32(f, (*b == 0xe8 || *b == 0xe9), get_be32, set_le32)
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}
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// scan
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static int s_sw32_e8(Filter *f)
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{
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SW32(f, (*b == 0xe8), get_le32, set_dummy)
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}
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static int s_sw32_e9(Filter *f)
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{
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SW32(f, (*b == 0xe9), get_le32, set_dummy)
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}
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static int s_sw32_e8e9(Filter *f)
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{
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SW32(f, (*b == 0xe8 || *b == 0xe9), get_le32, set_dummy)
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}
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#undef SW32
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/*
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vi:ts=4:et:nowrap
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*/
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