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git.ipfire.org Git - thirdparty/u-boot.git/blob - fs/jffs2/compr_rubin.c
2 * JFFS2 -- Journalling Flash File System, Version 2.
4 * Copyright (C) 2001 Red Hat, Inc.
6 * Created by Arjan van de Ven <arjanv@redhat.com>
8 * Heavily modified by Russ Dill <Russ.Dill@asu.edu> in an attempt at
11 * The original JFFS, from which the design for JFFS2 was derived,
12 * was designed and implemented by Axis Communications AB.
14 * The contents of this file are subject to the Red Hat eCos Public
15 * License Version 1.1 (the "Licence"); you may not use this file
16 * except in compliance with the Licence. You may obtain a copy of
17 * the Licence at http://www.redhat.com/
19 * Software distributed under the Licence is distributed on an "AS IS"
20 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.
21 * See the Licence for the specific language governing rights and
22 * limitations under the Licence.
24 * The Original Code is JFFS2 - Journalling Flash File System, version 2
26 * Alternatively, the contents of this file may be used under the
27 * terms of the GNU General Public License version 2 (the "GPL"), in
28 * which case the provisions of the GPL are applicable instead of the
29 * above. If you wish to allow the use of your version of this file
30 * only under the terms of the GPL and not to allow others to use your
31 * version of this file under the RHEPL, indicate your decision by
32 * deleting the provisions above and replace them with the notice and
33 * other provisions required by the GPL. If you do not delete the
34 * provisions above, a recipient may use your version of this file
35 * under either the RHEPL or the GPL.
37 * $Id: compr_rubin.c,v 1.2 2002/01/24 22:58:42 rfeany Exp $
42 #include <jffs2/jffs2.h>
43 #include <jffs2/compr_rubin.h>
46 void rubin_do_decompress(unsigned char *bits
, unsigned char *in
,
47 unsigned char *page_out
, __u32 destlen
)
49 register char *curr
= (char *)page_out
;
50 char *end
= (char *)(page_out
+ destlen
);
51 register unsigned long temp
;
52 register unsigned long result
;
53 register unsigned long p
;
54 register unsigned long q
;
55 register unsigned long rec_q
;
56 register unsigned long bit
;
66 p
= (long) (2 * UPPER_BIT_RUBIN
);
69 rec_q
= (in
[0] << 8) | in
[1];
75 for (i
= 0; i
< 8; i
++) {
78 while ((q
& UPPER_BIT_RUBIN
) || ((p
+ q
) <= UPPER_BIT_RUBIN
)) {
79 q
&= ~UPPER_BIT_RUBIN
;
82 rec_q
&= ~UPPER_BIT_RUBIN
;
84 rec_q
|= (temp
>> (bit
++ ^ 7)) & 1;
89 in
= (unsigned char *)p
;
92 i0
= (bits
[i
] * p
) >> 8;
95 /* if it fails, it fails, we have our crc
96 if (i0 >= p) i0 = p - 1; */
100 /* result |= 0x00; */
112 void dynrubin_decompress(unsigned char *data_in
, unsigned char *cpage_out
,
113 unsigned long sourcelen
, unsigned long dstlen
)
115 unsigned char bits
[8];
119 bits
[c
] = (256 - data_in
[c
]);
121 rubin_do_decompress(bits
, data_in
+8, cpage_out
, dstlen
);