forked from antirez/smaz
-
Notifications
You must be signed in to change notification settings - Fork 8
/
case.c
160 lines (144 loc) · 4.16 KB
/
case.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
/*
Copyright (C) 2012 Paul Gardner-Stephen
This program 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.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef UNDER_CONTROL
#define UNDER_CONTROL
#define COMMON
#undef FUNC
#undef ENCODING
#define FUNC(Y) decode ## Y
#include "case.c"
#undef COMMON
#undef FUNC
#define ENCODING
#define FUNC(Y) encode ## Y
#endif
#ifdef COMMON
#include <stdio.h>
#include <strings.h>
#include <math.h>
#include <stdlib.h>
#include <unistd.h>
#include <ctype.h>
#include "arithmetic.h"
#include "charset.h"
#include "packed_stats.h"
#include "unicode.h"
int stripCase(unsigned short *in,int in_len,unsigned short *out)
{
int l=0;
int i;
for(i=0;i<in_len;i++) {
if (in[i]<0x80)
out[l++]=tolower(in[i]);
else out[l++]=in[i];
}
return 0;
}
int mungeCase(unsigned short *m,int len)
{
int i;
/* Change isolated I's to i, provided preceeding char is lower-case
(so that we don't mess up all-caps).
*/
for(i=1;i<(len-1);i++)
if (m[i]<0x80)
if (tolower(m[i])=='i'&&(!isalpha(m[i-1]))&&(!isalpha(m[i+1])))
{
m[i]^=0x20;
}
return 0;
}
#endif
int FUNC(CaseModel1)(range_coder *c,unsigned short *line,int len,stats_handle *h)
{
int wordNumber=0;
int wordPosn=-1;
int lastWordInitialCase=0;
int lastWordInitialCase2=0;
int lastCase=0;
int i;
// printf("caps eligble chars: ");
for(i=0;i<len;i++) {
int wordChar=charInWord(line[i]);
if (!wordChar) {
wordPosn=-1; lastCase=0;
} else {
if (isalpha(line[i])) {
if (wordPosn<0) wordNumber++;
wordPosn++;
int upper=-1;
// int caseEnd=0;
/* note if end of word (which includes end of message,
implicitly detected here by finding null at end of string */
// if (!charInWord(line[i+1])) caseEnd=1;
if (wordPosn==0) {
/* first letter of word, so can only use 1st-order model */
unsigned int frequencies[1]={h->caseposn1[0][0]};
if (i==0) frequencies[0]=h->casestartofmessage[0][0];
else if (wordNumber>1&&wordPosn==0) {
/* start of word, so use model that considers initial case of
previous word */
frequencies[0]=h->casestartofword2[lastWordInitialCase][0];
if (wordNumber>2)
frequencies[0]=
h->casestartofword3[lastWordInitialCase2][lastWordInitialCase][0];
if (0)
printf("last word began with case=%d, p_lower=%f\n",
lastWordInitialCase,
(frequencies[0]*1.0)/0x1000000
);
}
if (0) printf("case of first letter of word/message @ %d: p=%f\n",
i,(frequencies[0]*1.0)/0x1000000);
#ifdef ENCODING
upper=isupper(line[i])?1:0;
range_encode_symbol(c,frequencies,2,upper);
#else
upper=range_decode_symbol(c,frequencies,2);
#endif
} else {
/* subsequent letter, so can use case of previous letter in model */
if (wordPosn>79) wordPosn=79;
if (0) {
printf("case of first letter of word/message @ %d.%d: p=%f\n",
i,wordPosn,
(h->caseposn2[lastCase][wordPosn][0]*1.0)/0x1000000);
printf(" lastCase=%d, wordPosn=%d\n",lastCase,wordPosn);
}
int pos=wordPosn;
while ((!h->caseposn2[lastCase][pos][0])&&pos) pos--;
#ifdef ENCODING
upper=isupper(line[i])?1:0;
range_encode_symbol(c,h->caseposn2[lastCase][pos],2,upper);
#else
upper=range_decode_symbol(c,h->caseposn2[lastCase][pos],2);
#endif
}
if (upper==1) line[i]=toupper(line[i]);
if (isupper(line[i])) lastCase=1; else lastCase=0;
if (wordPosn==0) {
lastWordInitialCase2=lastWordInitialCase;
lastWordInitialCase=lastCase;
}
else if (upper==-1) {
fprintf(stderr,"%s(): character processed without determining case.\n",
__FUNCTION__);
exit(-1);
}
}
}
}
return 0;
}