root/ereg/regex/regexec.c

DEFINITIONS

1. API_EXPORT

/*
 * 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"

#define PHP_REGEX_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  unsigned 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; unsigned 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
 = API_EXPORT(int) 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.
 */
API_EXPORT(int)                         /* 0 success, REG_NOMATCH failure */
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, (unsigned char *)string, nmatch, pmatch, eflags));
        else
                return(lmatcher(g, (unsigned char *)string, nmatch, pmatch, eflags));
}