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comparison src/lzfu.c @ 16:c508ee15dfca

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switch to automake/autoconf
author carl
date Sun, 19 Feb 2006 18:47:46 -0800
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children 6fe121a971c9
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15:ac98f448b6ab 16:c508ee15dfca
1 /*
2 This program is free software; you can redistribute it and/or modify
3 it under the terms of the GNU General Public License as published by
4 the Free Software Foundation; either version 2 of the License, or
5 (at your option) any later version.
6
7 You should have received a copy of the GNU General Public License
8 along with this program; if not, write to the Free Software Foundation,
9 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
10 */
11
12 #include "define.h"
13 #include "libpst.h"
14 #include <sys/types.h>
15 #include <string.h>
16 #include <stdio.h>
17
18 #ifndef _MSC_VER
19 #include <stdint.h>
20 #endif
21
22 #ifdef _MSC_VER
23 #define uint32_t unsigned int
24 #endif
25
26 #include "lzfu.h"
27
28 #define LZFU_COMPRESSED 0x75465a4c
29 #define LZFU_UNCOMPRESSED 0x414c454d
30
31 // initital dictionary
32 #define LZFU_INITDICT "{\\rtf1\\ansi\\mac\\deff0\\deftab720{\\fonttbl;}" \
33 "{\\f0\\fnil \\froman \\fswiss \\fmodern \\fscrip" \
34 "t \\fdecor MS Sans SerifSymbolArialTimes Ne" \
35 "w RomanCourier{\\colortbl\\red0\\green0\\blue0" \
36 "\r\n\\par \\pard\\plain\\f0\\fs20\\b\\i\\u\\tab" \
37 "\\tx"
38 // initial length of dictionary
39 #define LZFU_INITLENGTH 207
40
41 // header for compressed rtf
42 typedef struct _lzfuheader {
43 uint32_t cbSize;
44 uint32_t cbRawSize;
45 uint32_t dwMagic;
46 uint32_t dwCRC;
47 } lzfuheader;
48
49
50 /**
51 We always need to add 0x10 to the buffer offset because we need to skip past the header info
52 */
53
54 unsigned char* lzfu_decompress (unsigned char* rtfcomp) {
55 // the dictionary buffer
56 unsigned char dict[4096];
57 // the dictionary pointer
58 unsigned int dict_length=0;
59 // the header of the lzfu block
60 lzfuheader lzfuhdr;
61 // container for the data blocks
62 unsigned char flags;
63 // temp value for determining the bits in the flag
64 unsigned char flag_mask;
65 unsigned int i, in_size;
66 unsigned char *out_buf;
67 unsigned int out_ptr = 0;
68
69 memcpy(dict, LZFU_INITDICT, LZFU_INITLENGTH);
70 dict_length = LZFU_INITLENGTH;
71 memcpy(&lzfuhdr, rtfcomp, sizeof(lzfuhdr));
72 LE32_CPU(lzfuhdr.cbSize); LE32_CPU(lzfuhdr.cbRawSize);
73 LE32_CPU(lzfuhdr.dwMagic); LE32_CPU(lzfuhdr.dwCRC);
74 /* printf("total size: %d\n", lzfuhdr.cbSize+4);
75 printf("raw size : %d\n", lzfuhdr.cbRawSize);
76 printf("compressed: %s\n", (lzfuhdr.dwMagic == LZFU_COMPRESSED ? "yes" : "no"));
77 printf("CRC : %#x\n", lzfuhdr.dwCRC);
78 printf("\n");*/
79 out_buf = (unsigned char*)xmalloc(lzfuhdr.cbRawSize+20); //plus 4 cause we have 2x'}' and a \0
80 in_size = 0;
81 // we add plus one here cause when referencing an array, the index is always one less
82 // (ie, when accessing 2 element array, highest index is [1])
83 while (in_size+0x11 < lzfuhdr.cbSize) {
84 memcpy(&flags, &(rtfcomp[in_size+0x10]), 1);
85 in_size += 1;
86
87 flag_mask = 1;
88 while (flag_mask != 0 && in_size+0x11 < lzfuhdr.cbSize) {
89 if (flag_mask & flags) {
90 // read 2 bytes from input
91 unsigned short int blkhdr, offset, length;
92 memcpy(&blkhdr, &(rtfcomp[in_size+0x10]), 2);
93 LE16_CPU(blkhdr);
94 in_size += 2;
95 /* swap the upper and lower bytes of blkhdr */
96 blkhdr = (((blkhdr&0xFF00)>>8)+
97 ((blkhdr&0x00FF)<<8));
98 /* the offset is the first 24 bits of the 32 bit value */
99 offset = (blkhdr&0xFFF0)>>4;
100 /* the length of the dict entry are the last 8 bits */
101 length = (blkhdr&0x000F)+2;
102 // add the value we are about to print to the dictionary
103 for (i=0; i < length; i++) {
104 unsigned char c1;
105 c1 = dict[(offset+i)%4096];
106 dict[dict_length]=c1;
107 dict_length = (dict_length+1) % 4096;
108 out_buf[out_ptr++] = c1;
109 }
110 } else {
111 // uncompressed chunk (single byte)
112 char c1 = rtfcomp[in_size+0x10];
113 in_size ++;
114 dict[dict_length] = c1;
115 dict_length = (dict_length+1)%4096;
116 out_buf[out_ptr++] = c1;
117 }
118 flag_mask <<= 1;
119 }
120 }
121 // the compressed version doesn't appear to drop the closing braces onto the doc.
122 // we should do that
123 out_buf[out_ptr++] = '}';
124 out_buf[out_ptr++] = '}';
125 out_buf[out_ptr++] = '\0';
126 return out_buf;
127 }