aboutsummaryrefslogtreecommitdiff
path: root/fs/jffs2/compr_lzo.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/jffs2/compr_lzo.c')
-rw-r--r--fs/jffs2/compr_lzo.c405
1 files changed, 405 insertions, 0 deletions
diff --git a/fs/jffs2/compr_lzo.c b/fs/jffs2/compr_lzo.c
new file mode 100644
index 000000000..e97c18f51
--- /dev/null
+++ b/fs/jffs2/compr_lzo.c
@@ -0,0 +1,405 @@
+/*
+ * JFFS2 -- Journalling Flash File System, Version 2.
+ *
+ * Copyright (C) 2004 Patrik Kluba,
+ * University of Szeged, Hungary
+ *
+ * For licensing information, see the file 'LICENCE' in the
+ * jffs2 directory.
+ *
+ * $Id: compr_lzo.c,v 1.3 2004/06/23 16:34:39 havasi Exp $
+ *
+ */
+
+/*
+ LZO1X-1 (and -999) compression module for jffs2
+ based on the original LZO sources
+*/
+
+/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*- */
+
+/*
+ Original copyright notice follows:
+
+ lzo1x_9x.c -- implementation of the LZO1X-999 compression algorithm
+ lzo_ptr.h -- low-level pointer constructs
+ lzo_swd.ch -- sliding window dictionary
+ lzoconf.h -- configuration for the LZO real-time data compression library
+ lzo_mchw.ch -- matching functions using a window
+ minilzo.c -- mini subset of the LZO real-time data compression library
+ config1x.h -- configuration for the LZO1X algorithm
+ lzo1x.h -- public interface of the LZO1X compression algorithm
+
+ These files are part of the LZO real-time data compression library.
+
+ Copyright (C) 1996-2002 Markus Franz Xaver Johannes Oberhumer
+ All Rights Reserved.
+
+ The LZO library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of
+ the License, or (at your option) any later version.
+
+ The LZO library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with the LZO library; see the file COPYING.
+ If not, write to the Free Software Foundation, Inc.,
+ 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+ Markus F.X.J. Oberhumer
+ <markus@oberhumer.com>
+*/
+
+/*
+
+ 2004-02-16 pajko <pajko(AT)halom(DOT)u-szeged(DOT)hu>
+ Initial release
+ -removed all 16 bit code
+ -all sensitive data will be on 4 byte boundary
+ -removed check parts for library use
+ -removed all but LZO1X-* compression
+
+*/
+
+
+#include <config.h>
+#if ((CONFIG_COMMANDS & CFG_CMD_JFFS2) && defined(CONFIG_JFFS2_LZO))
+
+#include <linux/stddef.h>
+#include <jffs2/jffs2.h>
+#include <jffs2/compr_rubin.h>
+
+/* Integral types that have *exactly* the same number of bits as a lzo_voidp */
+typedef unsigned long lzo_ptr_t;
+typedef long lzo_sptr_t;
+
+/* data type definitions */
+#define U32 unsigned long
+#define S32 signed long
+#define I32 long
+#define U16 unsigned short
+#define S16 signed short
+#define I16 short
+#define U8 unsigned char
+#define S8 signed char
+#define I8 char
+
+#define M1_MAX_OFFSET 0x0400
+#define M2_MAX_OFFSET 0x0800
+#define M3_MAX_OFFSET 0x4000
+#define M4_MAX_OFFSET 0xbfff
+
+#define __COPY4(dst,src) * (lzo_uint32p)(dst) = * (const lzo_uint32p)(src)
+#define COPY4(dst,src) __COPY4((lzo_ptr_t)(dst),(lzo_ptr_t)(src))
+
+#define TEST_IP (ip < ip_end)
+#define TEST_OP (op <= op_end)
+
+#define NEED_IP(x) \
+ if ((lzo_uint)(ip_end - ip) < (lzo_uint)(x)) goto input_overrun
+#define NEED_OP(x) \
+ if ((lzo_uint)(op_end - op) < (lzo_uint)(x)) goto output_overrun
+#define TEST_LOOKBEHIND(m_pos,out) if (m_pos < out) goto lookbehind_overrun
+
+typedef U32 lzo_uint32;
+typedef I32 lzo_int32;
+typedef U32 lzo_uint;
+typedef I32 lzo_int;
+typedef int lzo_bool;
+
+#define lzo_byte U8
+#define lzo_bytep U8 *
+#define lzo_charp char *
+#define lzo_voidp void *
+#define lzo_shortp short *
+#define lzo_ushortp unsigned short *
+#define lzo_uint32p lzo_uint32 *
+#define lzo_int32p lzo_int32 *
+#define lzo_uintp lzo_uint *
+#define lzo_intp lzo_int *
+#define lzo_voidpp lzo_voidp *
+#define lzo_bytepp lzo_bytep *
+#define lzo_sizeof_dict_t sizeof(lzo_bytep)
+
+#define LZO_E_OK 0
+#define LZO_E_ERROR (-1)
+#define LZO_E_OUT_OF_MEMORY (-2) /* not used right now */
+#define LZO_E_NOT_COMPRESSIBLE (-3) /* not used right now */
+#define LZO_E_INPUT_OVERRUN (-4)
+#define LZO_E_OUTPUT_OVERRUN (-5)
+#define LZO_E_LOOKBEHIND_OVERRUN (-6)
+#define LZO_E_EOF_NOT_FOUND (-7)
+#define LZO_E_INPUT_NOT_CONSUMED (-8)
+
+#define PTR(a) ((lzo_ptr_t) (a))
+#define PTR_LINEAR(a) PTR(a)
+#define PTR_ALIGNED_4(a) ((PTR_LINEAR(a) & 3) == 0)
+#define PTR_ALIGNED_8(a) ((PTR_LINEAR(a) & 7) == 0)
+#define PTR_ALIGNED2_4(a,b) (((PTR_LINEAR(a) | PTR_LINEAR(b)) & 3) == 0)
+#define PTR_ALIGNED2_8(a,b) (((PTR_LINEAR(a) | PTR_LINEAR(b)) & 7) == 0)
+#define PTR_LT(a,b) (PTR(a) < PTR(b))
+#define PTR_GE(a,b) (PTR(a) >= PTR(b))
+#define PTR_DIFF(a,b) ((lzo_ptrdiff_t) (PTR(a) - PTR(b)))
+#define pd(a,b) ((lzo_uint) ((a)-(b)))
+
+typedef ptrdiff_t lzo_ptrdiff_t;
+
+static int
+lzo1x_decompress (const lzo_byte * in, lzo_uint in_len,
+ lzo_byte * out, lzo_uintp out_len, lzo_voidp wrkmem)
+{
+ register lzo_byte *op;
+ register const lzo_byte *ip;
+ register lzo_uint t;
+
+ register const lzo_byte *m_pos;
+
+ const lzo_byte *const ip_end = in + in_len;
+ lzo_byte *const op_end = out + *out_len;
+
+ *out_len = 0;
+
+ op = out;
+ ip = in;
+
+ if (*ip > 17)
+ {
+ t = *ip++ - 17;
+ if (t < 4)
+ goto match_next;
+ NEED_OP (t);
+ NEED_IP (t + 1);
+ do
+ *op++ = *ip++;
+ while (--t > 0);
+ goto first_literal_run;
+ }
+
+ while (TEST_IP && TEST_OP)
+ {
+ t = *ip++;
+ if (t >= 16)
+ goto match;
+ if (t == 0)
+ {
+ NEED_IP (1);
+ while (*ip == 0)
+ {
+ t += 255;
+ ip++;
+ NEED_IP (1);
+ }
+ t += 15 + *ip++;
+ }
+ NEED_OP (t + 3);
+ NEED_IP (t + 4);
+ if (PTR_ALIGNED2_4 (op, ip))
+ {
+ COPY4 (op, ip);
+
+ op += 4;
+ ip += 4;
+ if (--t > 0)
+ {
+ if (t >= 4)
+ {
+ do
+ {
+ COPY4 (op, ip);
+ op += 4;
+ ip += 4;
+ t -= 4;
+ }
+ while (t >= 4);
+ if (t > 0)
+ do
+ *op++ = *ip++;
+ while (--t > 0);
+ }
+ else
+ do
+ *op++ = *ip++;
+ while (--t > 0);
+ }
+ }
+ else
+ {
+ *op++ = *ip++;
+ *op++ = *ip++;
+ *op++ = *ip++;
+ do
+ *op++ = *ip++;
+ while (--t > 0);
+ }
+ first_literal_run:
+
+ t = *ip++;
+ if (t >= 16)
+ goto match;
+
+ m_pos = op - (1 + M2_MAX_OFFSET);
+ m_pos -= t >> 2;
+ m_pos -= *ip++ << 2;
+ TEST_LOOKBEHIND (m_pos, out);
+ NEED_OP (3);
+ *op++ = *m_pos++;
+ *op++ = *m_pos++;
+ *op++ = *m_pos;
+
+ goto match_done;
+
+ while (TEST_IP && TEST_OP)
+ {
+ match:
+ if (t >= 64)
+ {
+ m_pos = op - 1;
+ m_pos -= (t >> 2) & 7;
+ m_pos -= *ip++ << 3;
+ t = (t >> 5) - 1;
+ TEST_LOOKBEHIND (m_pos, out);
+ NEED_OP (t + 3 - 1);
+ goto copy_match;
+
+ }
+ else if (t >= 32)
+ {
+ t &= 31;
+ if (t == 0)
+ {
+ NEED_IP (1);
+ while (*ip == 0)
+ {
+ t += 255;
+ ip++;
+ NEED_IP (1);
+ }
+ t += 31 + *ip++;
+ }
+
+ m_pos = op - 1;
+ m_pos -= (ip[0] >> 2) + (ip[1] << 6);
+
+ ip += 2;
+ }
+ else if (t >= 16)
+ {
+ m_pos = op;
+ m_pos -= (t & 8) << 11;
+
+ t &= 7;
+ if (t == 0)
+ {
+ NEED_IP (1);
+ while (*ip == 0)
+ {
+ t += 255;
+ ip++;
+ NEED_IP (1);
+ }
+ t += 7 + *ip++;
+ }
+
+ m_pos -= (ip[0] >> 2) + (ip[1] << 6);
+
+ ip += 2;
+ if (m_pos == op)
+ goto eof_found;
+ m_pos -= 0x4000;
+ }
+ else
+ {
+
+ m_pos = op - 1;
+ m_pos -= t >> 2;
+ m_pos -= *ip++ << 2;
+ TEST_LOOKBEHIND (m_pos, out);
+ NEED_OP (2);
+ *op++ = *m_pos++;
+ *op++ = *m_pos;
+
+ goto match_done;
+ }
+
+ TEST_LOOKBEHIND (m_pos, out);
+ NEED_OP (t + 3 - 1);
+ if (t >= 2 * 4 - (3 - 1)
+ && PTR_ALIGNED2_4 (op, m_pos))
+ {
+ COPY4 (op, m_pos);
+ op += 4;
+ m_pos += 4;
+ t -= 4 - (3 - 1);
+ do
+ {
+ COPY4 (op, m_pos);
+ op += 4;
+ m_pos += 4;
+ t -= 4;
+ }
+ while (t >= 4);
+ if (t > 0)
+ do
+ *op++ = *m_pos++;
+ while (--t > 0);
+ }
+ else
+
+ {
+ copy_match:
+ *op++ = *m_pos++;
+ *op++ = *m_pos++;
+ do
+ *op++ = *m_pos++;
+ while (--t > 0);
+ }
+
+ match_done:
+ t = ip[-2] & 3;
+
+ if (t == 0)
+ break;
+
+ match_next:
+ NEED_OP (t);
+ NEED_IP (t + 1);
+ do
+ *op++ = *ip++;
+ while (--t > 0);
+ t = *ip++;
+ }
+ }
+ *out_len = op - out;
+ return LZO_E_EOF_NOT_FOUND;
+
+ eof_found:
+ *out_len = op - out;
+ return (ip == ip_end ? LZO_E_OK :
+ (ip <
+ ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
+
+ input_overrun:
+ *out_len = op - out;
+ return LZO_E_INPUT_OVERRUN;
+
+ output_overrun:
+ *out_len = op - out;
+ return LZO_E_OUTPUT_OVERRUN;
+
+ lookbehind_overrun:
+ *out_len = op - out;
+ return LZO_E_LOOKBEHIND_OVERRUN;
+}
+
+int lzo_decompress(unsigned char *data_in, unsigned char *cpage_out,
+ u32 srclen, u32 destlen)
+{
+ lzo_uint outlen = destlen;
+ return lzo1x_decompress (data_in, srclen, cpage_out, &outlen, NULL);
+}
+
+#endif /* ((CONFIG_COMMANDS & CFG_CMD_JFFS2) && defined(CONFIG_JFFS2_LZO)) */