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
226
227
228
229
230
231
232
233
|
/*--------------------------------------------------------------------*/
/*--- A simple sequence matching facility. ---*/
/*--- m_seqmatch.c ---*/
/*--------------------------------------------------------------------*/
/*
This file is part of Valgrind, a dynamic binary instrumentation
framework.
Copyright (C) 2008-2009 OpenWorks Ltd
info@open-works.co.uk
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., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
#include "pub_core_basics.h"
#include "pub_core_libcassert.h"
#include "pub_core_libcbase.h" // VG_(strlen)
#include "pub_core_seqmatch.h" // self
/* ---------------------------------------------------------------------
A simple sequence matching facility
------------------------------------------------------------------ */
/* See detailed comment in include/pub_tool_seqmatch.h about this. */
Bool VG_(generic_match) (
Bool matchAll,
void* patt, SizeT szbPatt, UWord nPatt, UWord ixPatt,
void* input, SizeT szbInput, UWord nInput, UWord ixInput,
Bool (*pIsStar)(void*),
Bool (*pIsQuery)(void*),
Bool (*pattEQinp)(void*,void*)
)
{
/* This is the spec, written in my favourite formal specification
language. It specifies non-greedy matching of '*'s.
ma ('*':ps) (i:is) = ma ps (i:is) || ma ('*':ps) is
ma ('*':ps) [] = ma ps []
ma ('?':ps) (i:is) = ma ps is
ma ('?':ps) [] = False
ma (p:ps) (i:is) = p == i && ma ps is
ma (p:ps) [] = False
ma [] (i:is) = False -- m-all, True for m-prefix
ma [] [] = True
*/
Bool havePatt, haveInput;
void *currPatt, *currInput;
tailcall:
vg_assert(nPatt >= 0 && nPatt < 1000000); /* arbitrary */
vg_assert(nInput >= 0 && nInput < 1000000); /* arbitrary */
vg_assert(ixPatt >= 0 && ixPatt <= nPatt);
vg_assert(ixInput >= 0 && ixInput <= nInput);
havePatt = ixPatt < nPatt;
haveInput = ixInput < nInput;
/* No specific need to set NULL when !have{Patt,Input}, but guards
against inadvertantly dereferencing an out of range pointer to
the pattern or input arrays. */
currPatt = havePatt ? ((Char*)patt) + szbPatt * ixPatt : NULL;
currInput = haveInput ? ((Char*)input) + szbInput * ixInput : NULL;
// Deal with the complex case first: wildcards. Do frugal
// matching. When encountering a '*', first skip no characters
// at all, and see if the rest of the match still works. Only if
// that fails do we then skip a character, and retry at the next
// position.
//
// ma ('*':ps) (i:is) = ma ps (i:is) || ma ('*':ps) is
//
// If we're out of input, check the rest of the pattern matches
// the empty input. This really means can only be be empty or
// composed entirely of '*'s.
//
// ma ('*':ps) [] = ma ps []
//
if (havePatt && pIsStar(currPatt)) {
if (haveInput) {
// ma ('*':ps) (i:is) = ma ps (i:is) || ma ('*':ps) is
// we unavoidably have to make a real recursive call for the
// first half of the OR, since this isn't straight tail-recursion.
if (VG_(generic_match)( matchAll,
patt, szbPatt, nPatt, ixPatt+1,
input,szbInput,nInput, ixInput+0,
pIsStar,pIsQuery,pattEQinp) ) {
return True;
}
// but we can tail-recurse for the second call
ixInput++; goto tailcall;
} else {
// ma ('*':ps) [] = ma ps []
ixPatt++; goto tailcall;
}
}
// simpler cases now. Deal with '?' wildcards.
//
// ma ('?':ps) (i:is) = ma ps is
// ma ('?':ps) [] = False
if (havePatt && pIsQuery(currPatt)) {
if (haveInput) {
ixPatt++; ixInput++; goto tailcall;
} else {
return False;
}
}
// obvious case with literal chars in the pattern
//
// ma (p:ps) (i:is) = p == i && ma ps is
if (havePatt && haveInput) {
if (!pattEQinp(currPatt,currInput)) return False;
ixPatt++; ixInput++; goto tailcall;
}
// if we run out of input before we run out of pattern, we must fail
// ma (p:ps) [] = False
if (havePatt && !haveInput) return False;
// if we run out of pattern before we run out of input, the
// verdict depends on the matching mode. If we are trying to
// match exactly (the pattern must consume the entire input)
// then the outcome is failure. However, if we're merely attempting
// to match some prefix of the input, then we have been successful.
//
// ma [] (i:is) = False -- m-all, True for m-prefix
if (!havePatt && haveInput) {
return matchAll ? False // match-all
: True; // match-prefix
}
// finally, if both sequence and input are both completely
// consumed, then we were successful, regardless of matching mode.
if (!havePatt && !haveInput) return True;
// end of cases
vg_assert(0);
}
/* And a parameterization of the above, to make it do
string matching.
*/
static Bool charIsStar ( void* pV ) { return *(Char*)pV == '*'; }
static Bool charIsQuery ( void* pV ) { return *(Char*)pV == '?'; }
static Bool char_p_EQ_i ( void* pV, void* cV ) {
Char p = *(Char*)pV;
Char c = *(Char*)cV;
vg_assert(p != '*' && p != '?');
return p == c;
}
Bool VG_(string_match) ( const Char* patt, const Char* input )
{
return VG_(generic_match)(
True/* match-all */,
(void*)patt, sizeof(UChar), VG_(strlen)(patt), 0,
(void*)input, sizeof(UChar), VG_(strlen)(input), 0,
charIsStar, charIsQuery, char_p_EQ_i
);
}
// test cases for the matcher (in match-all mode)
// typedef struct { char* patt; char* input; Bool xres; } Test;
//
//static Test tests[] =
// {
// { "" ,"" , True },
// { "a" ,"" , False },
// { "a" ,"b" , False },
// { "a" ,"a" , True },
// { "a" ,"aa" , False },
// { "*" ,"" , True },
// { "**" ,"" , True },
// { "*" ,"abc", True },
// { "*a" ,"abc", False },
// { "*b" ,"abc", False },
// { "*bc" ,"abc", True },
// { "a*b" ,"abc", False },
// { "a*c" ,"abc", True },
// { "*c" ,"abc", True },
// { "c*c" ,"abc", False },
// { "abc*" ,"abc", True },
// { "abc**" ,"abc", True },
// { "**abc" ,"abc", True },
// { "**a*b*c**" ,"abc", True },
// { "**a*b*d**" ,"abc", False },
// { "a?b" ,"abc", False },
// { "a?c" ,"abc", True },
// { "?" ,"" , False },
// { "?" ,"a" , True },
// { "?" ,"ab" , False },
// { "abcd" ,"abc", False },
// { "ab" ,"abc", False },
// { NULL ,NULL , False }
// };
//
//int main ( void )
//{
// Test* t;
// for (t = tests; t->patt; t++) {
// printf("%10s %6s %s\n",
// t->patt, t->input,
// match_string_all((UChar*)t->patt,(UChar*)t->input,True)
// == t->xres
// ? "pass" : "FAIL" );
// }
// return 0;
//}
/*--------------------------------------------------------------------*/
/*--- end m_seqmatch.c ---*/
/*--------------------------------------------------------------------*/
|
