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-rw-r--r--regex/regexec.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/regex/regexec.c b/regex/regexec.c
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+++ b/regex/regexec.c
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+/*
+ * the outer shell of regexec()
+ *
+ * This file includes engine.c *twice*, after muchos fiddling with the
+ * macros that code uses. This lets the same code operate on two different
+ * representations for state sets.
+ */
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <ctype.h>
+#include <regex.h>
+
+#include "utils.h"
+#include "regex2.h"
+
+static int nope = 0; /* for use in asserts; shuts lint up */
+
+/* macros for manipulating states, small version */
+#define states unsigned
+#define states1 unsigned /* for later use in regexec() decision */
+#define CLEAR(v) ((v) = 0)
+#define SET0(v, n) ((v) &= ~((unsigned)1 << (n)))
+#define SET1(v, n) ((v) |= (unsigned)1 << (n))
+#define ISSET(v, n) ((v) & ((unsigned)1 << (n)))
+#define ASSIGN(d, s) ((d) = (s))
+#define EQ(a, b) ((a) == (b))
+#define STATEVARS int dummy /* dummy version */
+#define STATESETUP(m, n) /* nothing */
+#define STATETEARDOWN(m) /* nothing */
+#define SETUP(v) ((v) = 0)
+#define onestate unsigned
+#define INIT(o, n) ((o) = (unsigned)1 << (n))
+#define INC(o) ((o) <<= 1)
+#define ISSTATEIN(v, o) ((v) & (o))
+/* some abbreviations; note that some of these know variable names! */
+/* do "if I'm here, I can also be there" etc without branches */
+#define FWD(dst, src, n) ((dst) |= ((unsigned)(src)&(here)) << (n))
+#define BACK(dst, src, n) ((dst) |= ((unsigned)(src)&(here)) >> (n))
+#define ISSETBACK(v, n) ((v) & ((unsigned)here >> (n)))
+/* function names */
+#define SNAMES /* engine.c looks after details */
+
+#include "engine.c"
+
+/* now undo things */
+#undef states
+#undef CLEAR
+#undef SET0
+#undef SET1
+#undef ISSET
+#undef ASSIGN
+#undef EQ
+#undef STATEVARS
+#undef STATESETUP
+#undef STATETEARDOWN
+#undef SETUP
+#undef onestate
+#undef INIT
+#undef INC
+#undef ISSTATEIN
+#undef FWD
+#undef BACK
+#undef ISSETBACK
+#undef SNAMES
+
+/* macros for manipulating states, large version */
+#define states char *
+#define CLEAR(v) memset(v, 0, m->g->nstates)
+#define SET0(v, n) ((v)[n] = 0)
+#define SET1(v, n) ((v)[n] = 1)
+#define ISSET(v, n) ((v)[n])
+#define ASSIGN(d, s) memcpy(d, s, m->g->nstates)
+#define EQ(a, b) (memcmp(a, b, m->g->nstates) == 0)
+#define STATEVARS int vn; char *space
+#define STATESETUP(m, nv) { (m)->space = malloc((nv)*(m)->g->nstates); \
+ if ((m)->space == NULL) return(REG_ESPACE); \
+ (m)->vn = 0; }
+#define STATETEARDOWN(m) { free((m)->space); }
+#define SETUP(v) ((v) = &m->space[m->vn++ * m->g->nstates])
+#define onestate int
+#define INIT(o, n) ((o) = (n))
+#define INC(o) ((o)++)
+#define ISSTATEIN(v, o) ((v)[o])
+/* some abbreviations; note that some of these know variable names! */
+/* do "if I'm here, I can also be there" etc without branches */
+#define FWD(dst, src, n) ((dst)[here+(n)] |= (src)[here])
+#define BACK(dst, src, n) ((dst)[here-(n)] |= (src)[here])
+#define ISSETBACK(v, n) ((v)[here - (n)])
+/* function names */
+#define LNAMES /* flag */
+
+#include "engine.c"
+
+/*
+ - regexec - interface for matching
+ = extern int notbuiltin_regexec(const regex_t *, const char *, size_t, \
+ = regmatch_t [], int);
+ = #define REG_NOTBOL 00001
+ = #define REG_NOTEOL 00002
+ = #define REG_STARTEND 00004
+ = #define REG_TRACE 00400 // tracing of execution
+ = #define REG_LARGE 01000 // force large representation
+ = #define REG_BACKR 02000 // force use of backref code
+ *
+ * We put this here so we can exploit knowledge of the state representation
+ * when choosing which matcher to call. Also, by this point the matchers
+ * have been prototyped.
+ */
+int /* 0 success, REG_NOMATCH failure */
+notbuiltin_regexec(preg, string, nmatch, pmatch, eflags)
+const regex_t *preg;
+const char *string;
+size_t nmatch;
+regmatch_t pmatch[];
+int eflags;
+{
+ register struct re_guts *g = preg->re_g;
+#ifdef REDEBUG
+# define GOODFLAGS(f) (f)
+#else
+# define GOODFLAGS(f) ((f)&(REG_NOTBOL|REG_NOTEOL|REG_STARTEND))
+#endif
+
+ if (preg->re_magic != MAGIC1 || g->magic != MAGIC2)
+ return(REG_BADPAT);
+ assert(!(g->iflags&BAD));
+ if (g->iflags&BAD) /* backstop for no-debug case */
+ return(REG_BADPAT);
+ eflags = GOODFLAGS(eflags);
+
+ if (g->nstates <= CHAR_BIT*sizeof(states1) && !(eflags&REG_LARGE))
+ return(smatcher(g, (char *)string, nmatch, pmatch, eflags));
+ else
+ return(lmatcher(g, (char *)string, nmatch, pmatch, eflags));
+}