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
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
/* ecs - equivalence class routines */
/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Vern Paxson.
*
* The United States Government has rights in this work pursuant
* to contract no. DE-AC03-76SF00098 between the United States
* Department of Energy and the University of California.
*
* Redistribution and use in source and binary forms with or without
* modification are permitted provided that: (1) source distributions retain
* this entire copyright notice and comment, and (2) distributions including
* binaries display the following acknowledgement: ``This product includes
* software developed by the University of California, Berkeley and its
* contributors'' in the documentation or other materials provided with the
* distribution and in all advertising materials mentioning features or use
* of this software. Neither the name of the University nor the names of
* its contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
/* $Header: /home/daffy/u0/vern/flex/RCS/ecs.c,v 2.9 93/12/07 10:18:20 vern Exp $ */
#include "flexdef.h"
/* ccl2ecl - convert character classes to set of equivalence classes */
void ccl2ecl()
{
int i, ich, newlen, cclp, ccls, cclmec;
for ( i = 1; i <= lastccl; ++i )
{
/* We loop through each character class, and for each character
* in the class, add the character's equivalence class to the
* new "character" class we are creating. Thus when we are all
* done, character classes will really consist of collections
* of equivalence classes
*/
newlen = 0;
cclp = cclmap[i];
for ( ccls = 0; ccls < ccllen[i]; ++ccls )
{
ich = ccltbl[cclp + ccls];
cclmec = ecgroup[ich];
if ( cclmec > 0 )
{
ccltbl[cclp + newlen] = cclmec;
++newlen;
}
}
ccllen[i] = newlen;
}
}
/* cre8ecs - associate equivalence class numbers with class members
*
* fwd is the forward linked-list of equivalence class members. bck
* is the backward linked-list, and num is the number of class members.
*
* Returned is the number of classes.
*/
int cre8ecs( fwd, bck, num )
int fwd[], bck[], num;
{
int i, j, numcl;
numcl = 0;
/* Create equivalence class numbers. From now on, ABS( bck(x) )
* is the equivalence class number for object x. If bck(x)
* is positive, then x is the representative of its equivalence
* class.
*/
for ( i = 1; i <= num; ++i )
if ( bck[i] == NIL )
{
bck[i] = ++numcl;
for ( j = fwd[i]; j != NIL; j = fwd[j] )
bck[j] = -numcl;
}
return numcl;
}
/* mkeccl - update equivalence classes based on character class xtions
*
* synopsis
* Char ccls[];
* int lenccl, fwd[llsiz], bck[llsiz], llsiz, NUL_mapping;
* void mkeccl( Char ccls[], int lenccl, int fwd[llsiz], int bck[llsiz],
* int llsiz, int NUL_mapping );
*
* ccls contains the elements of the character class, lenccl is the
* number of elements in the ccl, fwd is the forward link-list of equivalent
* characters, bck is the backward link-list, and llsiz size of the link-list.
*
* NUL_mapping is the value which NUL (0) should be mapped to.
*/
void mkeccl( ccls, lenccl, fwd, bck, llsiz, NUL_mapping )
Char ccls[];
int lenccl, fwd[], bck[], llsiz, NUL_mapping;
{
int cclp, oldec, newec;
int cclm, i, j;
static unsigned char cclflags[CSIZE]; /* initialized to all '\0' */
/* Note that it doesn't matter whether or not the character class is
* negated. The same results will be obtained in either case.
*/
cclp = 0;
while ( cclp < lenccl )
{
cclm = ccls[cclp];
if ( NUL_mapping && cclm == 0 )
cclm = NUL_mapping;
oldec = bck[cclm];
newec = cclm;
j = cclp + 1;
for ( i = fwd[cclm]; i != NIL && i <= llsiz; i = fwd[i] )
{ /* look for the symbol in the character class */
for ( ; j < lenccl; ++j )
{
register int ccl_char;
if ( NUL_mapping && ccls[j] == 0 )
ccl_char = NUL_mapping;
else
ccl_char = ccls[j];
if ( ccl_char > i )
break;
if ( ccl_char == i && ! cclflags[j] )
{
/* We found an old companion of cclm
* in the ccl. Link it into the new
* equivalence class and flag it as
* having been processed.
*/
bck[i] = newec;
fwd[newec] = i;
newec = i;
/* Set flag so we don't reprocess. */
cclflags[j] = 1;
/* Get next equivalence class member. */
/* continue 2 */
goto next_pt;
}
}
/* Symbol isn't in character class. Put it in the old
* equivalence class.
*/
bck[i] = oldec;
if ( oldec != NIL )
fwd[oldec] = i;
oldec = i;
next_pt: ;
}
if ( bck[cclm] != NIL || oldec != bck[cclm] )
{
bck[cclm] = NIL;
fwd[oldec] = NIL;
}
fwd[newec] = NIL;
/* Find next ccl member to process. */
for ( ++cclp; cclflags[cclp] && cclp < lenccl; ++cclp )
{
/* Reset "doesn't need processing" flag. */
cclflags[cclp] = 0;
}
}
}
/* mkechar - create equivalence class for single character */
void mkechar( tch, fwd, bck )
int tch, fwd[], bck[];
{
/* If until now the character has been a proper subset of
* an equivalence class, break it away to create a new ec
*/
if ( fwd[tch] != NIL )
bck[fwd[tch]] = bck[tch];
if ( bck[tch] != NIL )
fwd[bck[tch]] = fwd[tch];
fwd[tch] = NIL;
bck[tch] = NIL;
}
|
