1 /*-
2 * Copyright (c) 1992, 1993, 1994 Henry Spencer.
3 * Copyright (c) 1992, 1993, 1994
4 * The Regents of the University of California. All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Henry Spencer.
8 *
9 * %sccs.include.redist.c%
10 *
11 * @(#)regexec.c 8.3 (Berkeley) 03/20/94
12 */
13
14 #if defined(LIBC_SCCS) && !defined(lint)
15 static char sccsid[] = "@(#)regexec.c 8.3 (Berkeley) 03/20/94";
16 #endif /* LIBC_SCCS and not lint */
17
18 /*
19 * the outer shell of regexec()
20 *
21 * This file includes engine.c *twice*, after muchos fiddling with the
22 * macros that code uses. This lets the same code operate on two different
23 * representations for state sets.
24 */
25 #include <sys/types.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <limits.h>
30 #include <ctype.h>
31 #include <regex.h>
32
33 #include "utils.h"
34 #include "regex2.h"
35
36 static int nope = 0; /* for use in asserts; shuts lint up */
37
38 /* macros for manipulating states, small version */
39 #define states long
40 #define states1 states /* for later use in regexec() decision */
41 #define CLEAR(v) ((v) = 0)
42 #define SET0(v, n) ((v) &= ~(1 << (n)))
43 #define SET1(v, n) ((v) |= 1 << (n))
44 #define ISSET(v, n) ((v) & (1 << (n)))
45 #define ASSIGN(d, s) ((d) = (s))
46 #define EQ(a, b) ((a) == (b))
47 #define STATEVARS int dummy /* dummy version */
48 #define STATESETUP(m, n) /* nothing */
49 #define STATETEARDOWN(m) /* nothing */
50 #define SETUP(v) ((v) = 0)
51 #define onestate int
52 #define INIT(o, n) ((o) = (unsigned)1 << (n))
53 #define INC(o) ((o) <<= 1)
54 #define ISSTATEIN(v, o) ((v) & (o))
55 /* some abbreviations; note that some of these know variable names! */
56 /* do "if I'm here, I can also be there" etc without branches */
57 #define FWD(dst, src, n) ((dst) |= ((unsigned)(src)&(here)) << (n))
58 #define BACK(dst, src, n) ((dst) |= ((unsigned)(src)&(here)) >> (n))
59 #define ISSETBACK(v, n) ((v) & ((unsigned)here >> (n)))
60 /* function names */
61 #define SNAMES /* engine.c looks after details */
62
63 #include "engine.c"
64
65 /* now undo things */
66 #undef states
67 #undef CLEAR
68 #undef SET0
69 #undef SET1
70 #undef ISSET
71 #undef ASSIGN
72 #undef EQ
73 #undef STATEVARS
74 #undef STATESETUP
75 #undef STATETEARDOWN
76 #undef SETUP
77 #undef onestate
78 #undef INIT
79 #undef INC
80 #undef ISSTATEIN
81 #undef FWD
82 #undef BACK
83 #undef ISSETBACK
84 #undef SNAMES
85
86 /* macros for manipulating states, large version */
87 #define states char *
88 #define CLEAR(v) memset(v, 0, m->g->nstates)
89 #define SET0(v, n) ((v)[n] = 0)
90 #define SET1(v, n) ((v)[n] = 1)
91 #define ISSET(v, n) ((v)[n])
92 #define ASSIGN(d, s) memcpy(d, s, m->g->nstates)
93 #define EQ(a, b) (memcmp(a, b, m->g->nstates) == 0)
94 #define STATEVARS int vn; char *space
95 #define STATESETUP(m, nv) { (m)->space = malloc((nv)*(m)->g->nstates); \
96 if ((m)->space == NULL) return(REG_ESPACE); \
97 (m)->vn = 0; }
98 #define STATETEARDOWN(m) { free((m)->space); }
99 #define SETUP(v) ((v) = &m->space[m->vn++ * m->g->nstates])
100 #define onestate int
101 #define INIT(o, n) ((o) = (n))
102 #define INC(o) ((o)++)
103 #define ISSTATEIN(v, o) ((v)[o])
104 /* some abbreviations; note that some of these know variable names! */
105 /* do "if I'm here, I can also be there" etc without branches */
106 #define FWD(dst, src, n) ((dst)[here+(n)] |= (src)[here])
107 #define BACK(dst, src, n) ((dst)[here-(n)] |= (src)[here])
108 #define ISSETBACK(v, n) ((v)[here - (n)])
109 /* function names */
110 #define LNAMES /* flag */
111
112 #include "engine.c"
113
114 /*
115 - regexec - interface for matching
116 = extern int regexec(const regex_t *, const char *, size_t, \
117 = regmatch_t [], int);
118 = #define REG_NOTBOL 00001
119 = #define REG_NOTEOL 00002
120 = #define REG_STARTEND 00004
121 = #define REG_TRACE 00400 // tracing of execution
122 = #define REG_LARGE 01000 // force large representation
123 = #define REG_BACKR 02000 // force use of backref code
124 *
125 * We put this here so we can exploit knowledge of the state representation
126 * when choosing which matcher to call. Also, by this point the matchers
127 * have been prototyped.
128 */
129 int /* 0 success, REG_NOMATCH failure */
regexec(preg,string,nmatch,pmatch,eflags)130 regexec(preg, string, nmatch, pmatch, eflags)
131 const regex_t *preg;
132 const char *string;
133 size_t nmatch;
134 regmatch_t pmatch[];
135 int eflags;
136 {
137 register struct re_guts *g = preg->re_g;
138 #ifdef REDEBUG
139 # define GOODFLAGS(f) (f)
140 #else
141 # define GOODFLAGS(f) ((f)&(REG_NOTBOL|REG_NOTEOL|REG_STARTEND))
142 #endif
143
144 if (preg->re_magic != MAGIC1 || g->magic != MAGIC2)
145 return(REG_BADPAT);
146 assert(!(g->iflags&BAD));
147 if (g->iflags&BAD) /* backstop for no-debug case */
148 return(REG_BADPAT);
149 eflags = GOODFLAGS(eflags);
150
151 if (g->nstates <= CHAR_BIT*sizeof(states1) && !(eflags®_LARGE))
152 return(smatcher(g, (char *)string, nmatch, pmatch, eflags));
153 else
154 return(lmatcher(g, (char *)string, nmatch, pmatch, eflags));
155 }
156