Re: malloc with Studio Express 2008 C++

Ok. This is the top part of the file. The problem lies in the last
routine.
It is a bit long.

Look at the very end at function dfacomp
The line lcopy = (char*)malloc(len);
This code is in a separate .cpp file and it compiles fine. The main
function is in main.cpp and it calls dfacomp.
malloc works in main just fine. I don't see any of the includes that
redeclare malloc either. But then, I tried new instead and I get the same
error.

#include "Grepconfig.hpp"
#include <assert.h>

#include <ctype.h>

#include <stdio.h>

//#include <stddef.h>

#include <stdlib.h>

#include <string.h>

#include <locale.h>

#ifndef isgraph

#define isgraph(C) (isprint(C) && !isspace(C))

#endif

#define ISALPHA(C) isalpha(C)

#define ISUPPER(C) isupper(C)

#define ISLOWER(C) islower(C)

#define ISDIGIT(C) isdigit(C)

#define ISXDIGIT(C) isxdigit(C)

#define ISSPACE(C) isspace(C)

#define ISPUNCT(C) ispunct(C)

#define ISALNUM(C) isalnum(C)

#define ISPRINT(C) isprint(C)

#define ISGRAPH(C) isgraph(C)

#define ISCNTRL(C) iscntrl(C)

/* ISASCIIDIGIT differs from ISDIGIT, as follows:

- Its arg may be any int or unsigned int; it need not be an unsigned char.

- It's guaranteed to evaluate its argument exactly once.

- It's typically faster.

Posix 1003.2-1992 section 2.5.2.1 page 50 lines 1556-1558 says that

only '0' through '9' are digits. Prefer ISASCIIDIGIT to ISDIGIT unless

it's important to use the locale's definition of `digit' even when the

host does not conform to Posix. */

#define ISASCIIDIGIT(c) ((unsigned) (c) - '0' <= 9)

#ifndef _

# define _(Str) (Str)

#endif

/*//#include "Grepmbsupport.hpp" defines MBS_SUPPORT if appropriate */

#include "Grepregex.h"

#include "Grepdfa.h"

static void dfamust PARAMS ((struct dfa *dfa));

static ptr_t xcalloc PARAMS ((size_t n, size_t s));

static ptr_t xmalloc PARAMS ((size_t n));

static ptr_t xrealloc PARAMS ((ptr_t p, size_t n));

static int tstbit PARAMS ((unsigned b, charclass c));

static void setbit PARAMS ((unsigned b, charclass c));

static void clrbit PARAMS ((unsigned b, charclass c));

static void copyset PARAMS ((charclass src, charclass dst));

static void zeroset PARAMS ((charclass s));

static void notset PARAMS ((charclass s));

static int equal PARAMS ((charclass s1, charclass s2));

static int charclass_index PARAMS ((charclass s));

static int looking_at PARAMS ((const char *s));

static token lex PARAMS ((void));

static void addtok PARAMS ((token t));

static void atom PARAMS ((void));

static int nsubtoks PARAMS ((int tindex));

static void copytoks PARAMS ((int tindex, int ntokens));

static void closure PARAMS ((void));

static void branch PARAMS ((void));

static void regexp PARAMS ((int toplevel));

static void copy PARAMS ((position_set const *src, position_set *dst));

static void insert PARAMS ((position p, position_set *s));

static void merge PARAMS ((position_set const *s1, position_set const *s2,
position_set *m));

static void Delete PARAMS ((position p, position_set *s));

static int state_index PARAMS ((struct dfa *d, position_set const *s,

int newline, int letter));

static void build_state PARAMS ((int s, struct dfa *d));

static void build_state_zero PARAMS ((struct dfa *d));

static char *icatalloc PARAMS ((char *old, char *New));

static char *icpyalloc PARAMS ((char *string));

static char *istrstr PARAMS ((char *lookin, char *lookfor));

static void ifree PARAMS ((char *cp));

static void freelist PARAMS ((char **cpp));

static char **enlist PARAMS ((char **cpp, char *New, size_t len));

static char **comsubs PARAMS ((char *left, char *right));

static char **addlists PARAMS ((char **old, char **New));

static char **inboth PARAMS ((char **left, char **right));

static ptr_t

xcalloc (size_t n, size_t s)

{

ptr_t r = calloc(n, s);

if (!r)

dfaerror(_("Memory exhausted"));

return r;

}

static ptr_t

xmalloc (size_t n)

{

ptr_t r = malloc(n);

//assert(n != 0);

if (!r)

dfaerror(_("Memory exhausted"));

return r;

}

static ptr_t

xrealloc (ptr_t p, size_t n)

{

ptr_t r = realloc(p, n);

//assert(n != 0);

if (!r)

dfaerror(_("Memory exhausted"));

return r;

}

#define CALLOC(p, t, n) ((p) = (t *) xcalloc((size_t)(n), sizeof (t)))

#define MALLOC(p, t, n) ((p) = (t *) xmalloc((n) * sizeof (t)))

#define REALLOC(p, t, n) ((p) = (t *) xrealloc((ptr_t) (p), (n) * sizeof
(t)))

/* Reallocate an array of type t if nalloc is too small for index. */

#define REALLOC_IF_NECESSARY(p, t, nalloc, index) \

if ((index) >= (nalloc)) \

{ \

do \

(nalloc) *= 2; \

while ((index) >= (nalloc)); \

REALLOC(p, t, nalloc); \

}

/* Stuff pertaining to charclasses. */

static int

tstbit (unsigned b, charclass c)

{

return c[b / INTBITS] & 1 << b % INTBITS;

}

static void

setbit (unsigned b, charclass c)

{

c[b / INTBITS] |= 1 << b % INTBITS;

}

static void

clrbit (unsigned b, charclass c)

{

c[b / INTBITS] &= ~(1 << b % INTBITS);

}

static void

copyset (charclass src, charclass dst)

{

memcpy (dst, src, sizeof (charclass));

}

static void

zeroset (charclass s)

{

memset (s, 0, sizeof (charclass));

}

static void

notset (charclass s)

{

int i;

for (i = 0; i < CHARCLASS_INTS; ++i)

s[i] = ~s[i];

}

static int

equal (charclass s1, charclass s2)

{

return memcmp (s1, s2, sizeof (charclass)) == 0;

}

/* A pointer to the current dfa is kept here during parsing. */

static struct dfa *dfa;

/* Find the index of charclass s in dfa->charclasses, or allocate a new
charclass. */

static int

charclass_index (charclass s)

{

int i;

for (i = 0; i < dfa->cindex; ++i)

if (equal(s, dfa->charclasses[i]))

return i;

REALLOC_IF_NECESSARY(dfa->charclasses, charclass, dfa->calloc, dfa->cindex);

++dfa->cindex;

copyset(s, dfa->charclasses[i]);

return i;

}

/* Syntax bits controlling the behavior of the lexical analyzer. */

static reg_syntax_t syntax_bits, syntax_bits_set;

/* Flag for case-folding letters into sets. */

static int case_fold;

/* End-of-line byte in data. */

static unsigned char eolbyte;

/* Entry point to set syntax options. */

void

dfasyntax (reg_syntax_t bits, int fold, unsigned char eol)

{

syntax_bits_set = 1;

syntax_bits = bits;

case_fold = fold;

eolbyte = eol;

}

/* Like setbit, but if case is folded, set both cases of a letter. */

static void

setbit_case_fold (unsigned b, charclass c)

{

setbit (b, c);

if (case_fold)

{

if (ISUPPER (b))

setbit (tolower (b), c);

else if (ISLOWER (b))

setbit (toupper (b), c);

}

}

/* Lexical analyzer. All the dross that deals with the obnoxious

GNU Regex syntax bits is located here. The poor, suffering

reader is referred to the GNU Regex documentation for the

meaning of the @#%!@#%^!@ syntax bits. */

static char const *lexptr; /* Pointer to next input character. */

static int lexleft; /* Number of characters remaining. */

static token lasttok; /* Previous token returned; initially END. */

static int laststart; /* True if we're separated from beginning or (, |

only by zero-width characters. */

static int parens; /* Count of outstanding left parens. */

static int minrep, maxrep; /* Repeat counts for {m,n}. */

static int hard_LC_COLLATE; /* Nonzero if LC_COLLATE is hard. */

/* Note that characters become unsigned here. */

# define FETCH(c, eoferr) \

{ \

if (! lexleft) \

{ \

if (eoferr != 0) \

dfaerror (eoferr); \

else \

return lasttok = END; \

} \

(c) = (unsigned char) *lexptr++; \

--lexleft; \

}

#ifdef __STDC__

#define FUNC(F, P) static int F(int c) { return P(c); }

#else

#define FUNC(F, P) static int F(c) int c; { return P(c); }

#endif

FUNC(is_alpha, ISALPHA)

FUNC(is_upper, ISUPPER)

FUNC(is_lower, ISLOWER)

FUNC(is_digit, ISDIGIT)

FUNC(is_xdigit, ISXDIGIT)

FUNC(is_space, ISSPACE)

FUNC(is_punct, ISPUNCT)

FUNC(is_alnum, ISALNUM)

FUNC(is_print, ISPRINT)

FUNC(is_graph, ISGRAPH)

FUNC(is_cntrl, ISCNTRL)

static int

is_blank (int c)

{

return (c == ' ' || c == '\t');

}

/* The following list maps the names of the Posix named character classes

to predicate functions that determine whether a given character is in

the class. The leading [ has already been eaten by the lexical analyzer. */

static struct {

const char *name;

int (*pred) PARAMS ((int));

} const prednames[] = {

{ ":alpha:]", is_alpha },

{ ":upper:]", is_upper },

{ ":lower:]", is_lower },

{ ":digit:]", is_digit },

{ ":xdigit:]", is_xdigit },

{ ":space:]", is_space },

{ ":punct:]", is_punct },

{ ":alnum:]", is_alnum },

{ ":print:]", is_print },

{ ":graph:]", is_graph },

{ ":cntrl:]", is_cntrl },

{ ":blank:]", is_blank },

{ 0 }

};

/* Return non-zero if C is a `word-constituent' byte; zero otherwise. */

#define IS_WORD_CONSTITUENT(C) (ISALNUM(C) || (C) == '_')

static int

looking_at (char const *s)

{

size_t len;

len = strlen(s);

if (lexleft < len)

return 0;

return strncmp(s, lexptr, len) == 0;

}

static token

lex (void)

{

unsigned c, c1, c2;

int backslash = 0, invert;

charclass ccl;

int i;

/* Basic plan: We fetch a character. If it's a backslash,

we set the backslash flag and go through the loop again.

On the plus side, this avoids having a duplicate of the

main switch inside the backslash case. On the minus side,

it means that just about every case begins with

"if (backslash) ...". */

for (i = 0; i < 2; ++i)

{

FETCH(c, 0);

switch (c)

{

case '\\':

if (backslash)

goto normal_char;

if (lexleft == 0)

dfaerror(_("Unfinished \\ escape"));

backslash = 1;

break;

case '^':

if (backslash)

goto normal_char;

if (syntax_bits & RE_CONTEXT_INDEP_ANCHORS

|| lasttok == END

|| lasttok == LPAREN

|| lasttok == OR)

return lasttok = BEGLINE;

goto normal_char;

case '$':

if (backslash)

goto normal_char;

if (syntax_bits & RE_CONTEXT_INDEP_ANCHORS

|| lexleft == 0

|| (syntax_bits & RE_NO_BK_PARENS

? lexleft > 0 && *lexptr == ')'

: lexleft > 1 && lexptr[0] == '\\' && lexptr[1] == ')')

|| (syntax_bits & RE_NO_BK_VBAR

? lexleft > 0 && *lexptr == '|'

: lexleft > 1 && lexptr[0] == '\\' && lexptr[1] == '|')

|| ((syntax_bits & RE_NEWLINE_ALT)

&& lexleft > 0 && *lexptr == '\n'))

return lasttok = ENDLINE;

goto normal_char;

case '1':

case '2':

case '3':

case '4':

case '5':

case '6':

case '7':

case '8':

case '9':

if (backslash && !(syntax_bits & RE_NO_BK_REFS))

{

laststart = 0;

return lasttok = BACKREF;

}

goto normal_char;

case '`':

if (backslash && !(syntax_bits & RE_NO_GNU_OPS))

return lasttok = BEGLINE; /* FIXME: should be beginning of string */

goto normal_char;

case '\'':

if (backslash && !(syntax_bits & RE_NO_GNU_OPS))

return lasttok = ENDLINE; /* FIXME: should be end of string */

goto normal_char;

case '<':

if (backslash && !(syntax_bits & RE_NO_GNU_OPS))

return lasttok = BEGWORD;

goto normal_char;

case '>':

if (backslash && !(syntax_bits & RE_NO_GNU_OPS))

return lasttok = ENDWORD;

goto normal_char;

case 'b':

if (backslash && !(syntax_bits & RE_NO_GNU_OPS))

return lasttok = LIMWORD;

goto normal_char;

case 'B':

if (backslash && !(syntax_bits & RE_NO_GNU_OPS))

return lasttok = NOTLIMWORD;

goto normal_char;

case '?':

if (syntax_bits & RE_LIMITED_OPS)

goto normal_char;

if (backslash != ((syntax_bits & RE_BK_PLUS_QM) != 0))

goto normal_char;

if (!(syntax_bits & RE_CONTEXT_INDEP_OPS) && laststart)

goto normal_char;

return lasttok = QMARK;

case '*':

if (backslash)

goto normal_char;

if (!(syntax_bits & RE_CONTEXT_INDEP_OPS) && laststart)

goto normal_char;

return lasttok = STAR;

case '+':

if (syntax_bits & RE_LIMITED_OPS)

goto normal_char;

if (backslash != ((syntax_bits & RE_BK_PLUS_QM) != 0))

goto normal_char;

if (!(syntax_bits & RE_CONTEXT_INDEP_OPS) && laststart)

goto normal_char;

return lasttok = PLUS;

case '{':

if (!(syntax_bits & RE_INTERVALS))

goto normal_char;

if (backslash != ((syntax_bits & RE_NO_BK_BRACES) == 0))

goto normal_char;

if (!(syntax_bits & RE_CONTEXT_INDEP_OPS) && laststart)

goto normal_char;

if (syntax_bits & RE_NO_BK_BRACES)

{

/* Scan ahead for a valid interval; if it's not valid,

treat it as a literal '{'. */

int lo = -1, hi = -1;

char const *p = lexptr;

char const *lim = p + lexleft;

for (; p != lim && ISASCIIDIGIT (*p); p++)

lo = (lo < 0 ? 0 : lo * 10) + *p - '0';

if (p != lim && *p == ',')

while (++p != lim && ISASCIIDIGIT (*p))

hi = (hi < 0 ? 0 : hi * 10) + *p - '0';

else

hi = lo;

if (p == lim || *p != '}'

|| lo < 0 || RE_DUP_MAX < hi || (0 <= hi && hi < lo))

goto normal_char;

}

minrep = 0;

/* Cases:

{M} - exact count

{M,} - minimum count, maximum is infinity

{M,N} - M through N */

FETCH(c, _("unfinished repeat count"));

if (ISASCIIDIGIT (c))

{

minrep = c - '0';

for (;;)

{

FETCH(c, _("unfinished repeat count"));

if (! ISASCIIDIGIT (c))

break;

minrep = 10 * minrep + c - '0';

}

}

else

dfaerror(_("malformed repeat count"));

if (c == ',')

{

FETCH (c, _("unfinished repeat count"));

if (! ISASCIIDIGIT (c))

maxrep = -1;

else

{

maxrep = c - '0';

for (;;)

{

FETCH (c, _("unfinished repeat count"));

if (! ISASCIIDIGIT (c))

break;

maxrep = 10 * maxrep + c - '0';

}

if (0 <= maxrep && maxrep < minrep)

dfaerror (_("malformed repeat count"));

}

}

else

maxrep = minrep;

if (!(syntax_bits & RE_NO_BK_BRACES))

{

if (c != '\\')

dfaerror(_("malformed repeat count"));

FETCH(c, _("unfinished repeat count"));

}

if (c != '}')

dfaerror(_("malformed repeat count"));

laststart = 0;

return lasttok = REPMN;

case '|':

if (syntax_bits & RE_LIMITED_OPS)

goto normal_char;

if (backslash != ((syntax_bits & RE_NO_BK_VBAR) == 0))

goto normal_char;

laststart = 1;

return lasttok = OR;

case '\n':

if (syntax_bits & RE_LIMITED_OPS

|| backslash

|| !(syntax_bits & RE_NEWLINE_ALT))

goto normal_char;

laststart = 1;

return lasttok = OR;

case '(':

if (backslash != ((syntax_bits & RE_NO_BK_PARENS) == 0))

goto normal_char;

++parens;

laststart = 1;

return lasttok = LPAREN;

case ')':

if (backslash != ((syntax_bits & RE_NO_BK_PARENS) == 0))

goto normal_char;

if (parens == 0 && syntax_bits & RE_UNMATCHED_RIGHT_PAREN_ORD)

goto normal_char;

--parens;

laststart = 0;

return lasttok = RPAREN;

case '.':

if (backslash)

goto normal_char;

zeroset(ccl);

notset(ccl);

if (!(syntax_bits & RE_DOT_NEWLINE))

clrbit(eolbyte, ccl);

if (syntax_bits & RE_DOT_NOT_NULL)

clrbit('\0', ccl);

laststart = 0;

return lasttok = static_cast<token>(CSET + charclass_index(ccl));

case 'w':

case 'W':

if (!backslash || (syntax_bits & RE_NO_GNU_OPS))

goto normal_char;

zeroset(ccl);

for (c2 = 0; c2 < NOTCHAR; ++c2)

if (IS_WORD_CONSTITUENT(c2))

setbit(c2, ccl);

if (c == 'W')

notset(ccl);

laststart = 0;

return lasttok = static_cast<token>(CSET + charclass_index(ccl));

case '[':

if (backslash)

goto normal_char;

laststart = 0;

zeroset(ccl);

FETCH(c, _("Unbalanced ["));

if (c == '^')

{

FETCH(c, _("Unbalanced ["));

invert = 1;

}

else

invert = 0;

do

{

/* Nobody ever said this had to be fast. :-)

Note that if we're looking at some other [:...:]

construct, we just treat it as a bunch of ordinary

characters. We can do this because we assume

regex has checked for syntax errors before

dfa is ever called. */

if (c == '[' && (syntax_bits & RE_CHAR_CLASSES))

for (c1 = 0; prednames[c1].name; ++c1)

if (looking_at(prednames[c1].name))

{

int (*pred) PARAMS ((int)) = prednames[c1].pred;

for (c2 = 0; c2 < NOTCHAR; ++c2)

if ((*pred)(c2))

setbit_case_fold (c2, ccl);

lexptr += strlen(prednames[c1].name);

lexleft -= strlen(prednames[c1].name);

FETCH(c1, _("Unbalanced ["));

goto skip;

}

if (c == '\\' && (syntax_bits & RE_BACKSLASH_ESCAPE_IN_LISTS))

FETCH(c, _("Unbalanced ["));

FETCH(c1, _("Unbalanced ["));

if (c1 == '-')

{

FETCH(c2, _("Unbalanced ["));

if (c2 == ']')

{

/* In the case [x-], the - is an ordinary hyphen,

which is left in c1, the lookahead character. */

--lexptr;

++lexleft;

}

else

{

if (c2 == '\\'

&& (syntax_bits & RE_BACKSLASH_ESCAPE_IN_LISTS))

FETCH(c2, _("Unbalanced ["));

FETCH(c1, _("Unbalanced ["));

if (!hard_LC_COLLATE) {

for (; c <= c2; c++)

setbit_case_fold (c, ccl);

} else {

/* POSIX locales are painful - leave the decision to libc */

regex_t re;

char expr[6]; /* = { '[', c, '-', c2, ']', '\0' }; */

expr[0] = '['; expr[1] = c; expr[2] = '-';

expr[3] = c2; expr[4] = ']'; expr[5] = '\0';

if (regcomp (&re, expr, case_fold ? REG_ICASE : 0) == REG_NOERROR) {

for (c = 0; c < NOTCHAR; ++c) {

regmatch_t mat;

char buf[2]; /* = { c, '\0' }; */

buf[0] = c; buf[1] = '\0';

if (regexec (&re, buf, 1, &mat, 0) == REG_NOERROR

&& mat.rm_so == 0 && mat.rm_eo == 1)

setbit_case_fold (c, ccl);

}

regfree (&re);

}

}

continue;

}

}

setbit_case_fold (c, ccl);

skip:

;

}

while ((c = c1) != ']');

if (invert)

{

notset(ccl);

if (syntax_bits & RE_HAT_LISTS_NOT_NEWLINE)

clrbit(eolbyte, ccl);

}

return lasttok = static_cast<token>(CSET + charclass_index(ccl));

default:

normal_char:

laststart = 0;

if (case_fold && ISALPHA(c))

{

zeroset(ccl);

setbit_case_fold (c, ccl);

return lasttok = static_cast<token>(CSET + charclass_index(ccl));

}

return lasttok = static_cast<token>(c);

}

}

/* The above loop should consume at most a backslash

and some other character. */

abort();

return END; /* keeps pedantic compilers happy. */

}

/* Recursive descent parser for regular expressions. */

static token tok; /* Lookahead token. */

static int depth; /* Current depth of a hypothetical stack

holding deferred productions. This is

used to determine the depth that will be

required of the real stack later on in

dfaanalyze(). */

/* Add the given token to the parse tree, maintaining the depth count and

updating the maximum depth if necessary. */

static void

addtok (token t)

{

REALLOC_IF_NECESSARY(dfa->tokens, token, dfa->talloc, dfa->tindex);

dfa->tokens[dfa->tindex++] = t;

switch (t)

{

case QMARK:

case STAR:

case PLUS:

break;

case CAT:

case OR:

case ORTOP:

--depth;

break;

default:

++dfa->nleaves;

case EMPTY:

++depth;

break;

}

if (depth > dfa->depth)

dfa->depth = depth;

}

/* The grammar understood by the parser is as follows.

regexp:

regexp OR branch

branch

branch:

branch closure

closure

closure:

closure QMARK

closure STAR

closure PLUS

closure REPMN

atom

atom:

<normal character>

<multibyte character>

ANYCHAR

MBCSET

CSET

BACKREF

BEGLINE

ENDLINE

BEGWORD

ENDWORD

LIMWORD

NOTLIMWORD

CRANGE

LPAREN regexp RPAREN

<empty>

The parser builds a parse tree in postfix form in an array of tokens. */

static void

atom (void)

{

if ((tok >= 0 && tok < NOTCHAR) || tok >= CSET || tok == BACKREF

|| tok == BEGLINE || tok == ENDLINE || tok == BEGWORD

|| tok == ENDWORD || tok == LIMWORD || tok == NOTLIMWORD)

{

addtok(tok);

tok = lex();

}

else if (tok == CRANGE)

{

/* A character range like "[a-z]" in a locale other than "C" or

"POSIX". This range might any sequence of one or more

characters. Unfortunately the POSIX locale primitives give

us no practical way to find what character sequences might be

matched. Treat this approximately like "(.\1)" -- i.e. match

one character, and then punt to the full matcher. */

charclass ccl;

zeroset (ccl);

notset (ccl);

addtok (static_cast<token>(CSET + charclass_index (ccl)));

addtok (BACKREF);

addtok (CAT);

tok = lex ();

}

else if (tok == LPAREN)

{

tok = lex();

regexp(0);

if (tok != RPAREN)

dfaerror(_("Unbalanced ("));

tok = lex();

}

else

addtok(EMPTY);

}

/* Return the number of tokens in the given subexpression. */

static int

nsubtoks (int tindex)

{

int ntoks1;

switch (dfa->tokens[tindex - 1])

{

default:

return 1;

case QMARK:

case STAR:

case PLUS:

return 1 + nsubtoks(tindex - 1);

case CAT:

case OR:

case ORTOP:

ntoks1 = nsubtoks(tindex - 1);

return 1 + ntoks1 + nsubtoks(tindex - 1 - ntoks1);

}

}

/* Copy the given subexpression to the top of the tree. */

static void

copytoks (int tindex, int ntokens)

{

int i;

for (i = 0; i < ntokens; ++i)

addtok(dfa->tokens[tindex + i]);

}

static void

closure (void)

{

int tindex, ntokens, i;

atom();

while (tok == QMARK || tok == STAR || tok == PLUS || tok == REPMN)

if (tok == REPMN)

{

ntokens = nsubtoks(dfa->tindex);

tindex = dfa->tindex - ntokens;

if (maxrep < 0)

addtok(PLUS);

if (minrep == 0)

addtok(QMARK);

for (i = 1; i < minrep; ++i)

{

copytoks(tindex, ntokens);

addtok(CAT);

}

for (; i < maxrep; ++i)

{

copytoks(tindex, ntokens);

addtok(QMARK);

addtok(CAT);

}

tok = lex();

}

else

{

addtok(tok);

tok = lex();

}

}

static void

branch (void)

{

closure();

while (tok != RPAREN && tok != OR && tok >= 0)

{

closure();

addtok(CAT);

}

}

static void

regexp (int toplevel)

{

branch();

while (tok == OR)

{

tok = lex();

branch();

if (toplevel)

addtok(ORTOP);

else

addtok(OR);

}

}

/* Main entry point for the parser. S is a string to be parsed, len is the

length of the string, so s can include NUL characters. D is a pointer to

the struct dfa to parse into. */

void

dfaparse (char const *s, size_t len, struct dfa *d)

{

dfa = d;

lexptr = s;

lexleft = len;

lasttok = END;

laststart = 1;

parens = 0;

if (! syntax_bits_set)

dfaerror(_("No syntax specified"));

tok = lex();

depth = d->depth;

regexp(1);

if (tok != END)

dfaerror(_("Unbalanced )"));

addtok(static_cast<token>(END - d->nregexps));

addtok(CAT);

if (d->nregexps)

addtok(ORTOP);

++d->nregexps;

}

/* Some primitives for operating on sets of positions. */

/* Copy one set to another; the destination must be large enough. */

static void

copy (position_set const *src, position_set *dst)

{

int i;

for (i = 0; i < src->nelem; ++i)

dst->elems[i] = src->elems[i];

dst->nelem = src->nelem;

}

/* Insert a position in a set. Position sets are maintained in sorted

order according to index. If position already exists in the set with

the same index then their constraints are logically or'd together.

S->elems must point to an array large enough to hold the resulting set. */

static void

insert (position p, position_set *s)

{

int i;

position t1, t2;

for (i = 0; i < s->nelem && p.index < s->elems[i].index; ++i)

continue;

if (i < s->nelem && p.index == s->elems[i].index)

s->elems[i].constraint |= p.constraint;

else

{

t1 = p;

++s->nelem;

while (i < s->nelem)

{

t2 = s->elems[i];

s->elems[i++] = t1;

t1 = t2;

}

}

}

/* Merge two sets of positions into a third. The result is exactly as if

the positions of both sets were inserted into an initially empty set. */

static void

merge (position_set const *s1, position_set const *s2, position_set *m)

{

int i = 0, j = 0;

m->nelem = 0;

while (i < s1->nelem && j < s2->nelem)

if (s1->elems[i].index > s2->elems[j].index)

m->elems[m->nelem++] = s1->elems[i++];

else if (s1->elems[i].index < s2->elems[j].index)

m->elems[m->nelem++] = s2->elems[j++];

else

{

m->elems[m->nelem] = s1->elems[i++];

m->elems[m->nelem++].constraint |= s2->elems[j++].constraint;

}

while (i < s1->nelem)

m->elems[m->nelem++] = s1->elems[i++];

while (j < s2->nelem)

m->elems[m->nelem++] = s2->elems[j++];

}

/* Delete a position from a set. */

static void

Delete (position p, position_set *s)

{

int i;

for (i = 0; i < s->nelem; ++i)

if (p.index == s->elems[i].index)

break;

if (i < s->nelem)

for (--s->nelem; i < s->nelem; ++i)

s->elems[i] = s->elems[i + 1];

}

/* Find the index of the state corresponding to the given position set with

the given preceding context, or create a new state if there is no such

state. Newline and letter tell whether we got here on a newline or

letter, respectively. */

static int

state_index (struct dfa *d, position_set const *s, int newline, int letter)

{

int hash = 0;

int constraint;

int i, j;

newline = newline ? 1 : 0;

letter = letter ? 1 : 0;

for (i = 0; i < s->nelem; ++i)

hash ^= s->elems[i].index + s->elems[i].constraint;

/* Try to find a state that exactly matches the proposed one. */

for (i = 0; i < d->sindex; ++i)

{

if (hash != d->states[i].hash || s->nelem != d->states[i].elems.nelem

|| newline != d->states[i].newline || letter != d->states[i].letter)

continue;

for (j = 0; j < s->nelem; ++j)

if (s->elems[j].constraint

!= d->states[i].elems.elems[j].constraint

|| s->elems[j].index != d->states[i].elems.elems[j].index)

break;

if (j == s->nelem)

return i;

}

/* We'll have to create a new state. */

REALLOC_IF_NECESSARY(d->states, dfa_state, d->salloc, d->sindex);

d->states[i].hash = hash;

MALLOC(d->states[i].elems.elems, position, s->nelem);

copy(s, &d->states[i].elems);

d->states[i].newline = newline;

d->states[i].letter = letter;

d->states[i].backref = 0;

d->states[i].constraint = 0;

d->states[i].first_end = 0;

for (j = 0; j < s->nelem; ++j)

if (d->tokens[s->elems[j].index] < 0)

{

constraint = s->elems[j].constraint;

if (SUCCEEDS_IN_CONTEXT(constraint, newline, 0, letter, 0)

|| SUCCEEDS_IN_CONTEXT(constraint, newline, 0, letter, 1)

|| SUCCEEDS_IN_CONTEXT(constraint, newline, 1, letter, 0)

|| SUCCEEDS_IN_CONTEXT(constraint, newline, 1, letter, 1))

d->states[i].constraint |= constraint;

if (! d->states[i].first_end)

d->states[i].first_end = d->tokens[s->elems[j].index];

}

else if (d->tokens[s->elems[j].index] == BACKREF)

{

d->states[i].constraint = NO_CONSTRAINT;

d->states[i].backref = 1;

}

++d->sindex;

return i;

}

/* Find the epsilon closure of a set of positions. If any position of the
set

contains a symbol that matches the empty string in some context, replace

that position with the elements of its follow labeled with an appropriate

constraint. Repeat exhaustively until no funny positions are left.

S->elems must be large enough to hold the result. */

static void

epsclosure (position_set *s, struct dfa const *d)

{

int i, j;

int *visited;

position p, old;

MALLOC(visited, int, d->tindex);

for (i = 0; i < d->tindex; ++i)

visited[i] = 0;

for (i = 0; i < s->nelem; ++i)

if (d->tokens[s->elems[i].index] >= NOTCHAR

&& d->tokens[s->elems[i].index] != BACKREF

&& d->tokens[s->elems[i].index] < CSET)

{

old = s->elems[i];

p.constraint = old.constraint;

delete(s->elems[i], s);

if (visited[old.index])

{

--i;

continue;

}

visited[old.index] = 1;

switch (d->tokens[old.index])

{

case BEGLINE:

p.constraint &= BEGLINE_CONSTRAINT;

break;

case ENDLINE:

p.constraint &= ENDLINE_CONSTRAINT;

break;

case BEGWORD:

p.constraint &= BEGWORD_CONSTRAINT;

break;

case ENDWORD:

p.constraint &= ENDWORD_CONSTRAINT;

break;

case LIMWORD:

p.constraint &= LIMWORD_CONSTRAINT;

break;

case NOTLIMWORD:

p.constraint &= NOTLIMWORD_CONSTRAINT;

break;

default:

break;

}

for (j = 0; j < d->follows[old.index].nelem; ++j)

{

p.index = d->follows[old.index].elems[j].index;

insert(p, s);

}

/* Force rescan to start at the beginning. */

i = -1;

}

free(visited);

}

/* Perform bottom-up analysis on the parse tree, computing various
functions.

Note that at this point, we're pretending constructs like \< are real

characters rather than constraints on what can follow them.

Nullable: A node is nullable if it is at the root of a regexp that can

match the empty string.

* EMPTY leaves are nullable.

* No other leaf is nullable.

* A QMARK or STAR node is nullable.

* A PLUS node is nullable if its argument is nullable.

* A CAT node is nullable if both its arguments are nullable.

* An OR node is nullable if either argument is nullable.

Firstpos: The firstpos of a node is the set of positions (nonempty leaves)

that could correspond to the first character of a string matching the

regexp rooted at the given node.

* EMPTY leaves have empty firstpos.

* The firstpos of a nonempty leaf is that leaf itself.

* The firstpos of a QMARK, STAR, or PLUS node is the firstpos of its

argument.

* The firstpos of a CAT node is the firstpos of the left argument, union

the firstpos of the right if the left argument is nullable.

* The firstpos of an OR node is the union of firstpos of each argument.

Lastpos: The lastpos of a node is the set of positions that could

correspond to the last character of a string matching the regexp at

the given node.

* EMPTY leaves have empty lastpos.

* The lastpos of a nonempty leaf is that leaf itself.

* The lastpos of a QMARK, STAR, or PLUS node is the lastpos of its

argument.

* The lastpos of a CAT node is the lastpos of its right argument, union

the lastpos of the left if the right argument is nullable.

* The lastpos of an OR node is the union of the lastpos of each argument.

Follow: The follow of a position is the set of positions that could

correspond to the character following a character matching the node in

a string matching the regexp. At this point we consider special symbols

that match the empty string in some context to be just normal characters.

Later, if we find that a special symbol is in a follow set, we will

replace it with the elements of its follow, labeled with an appropriate

constraint.

* Every node in the firstpos of the argument of a STAR or PLUS node is in

the follow of every node in the lastpos.

* Every node in the firstpos of the second argument of a CAT node is in

the follow of every node in the lastpos of the first argument.

Because of the postfix representation of the parse tree, the depth-first

analysis is conveniently done by a linear scan with the aid of a stack.

Sets are stored as arrays of the elements, obeying a stack-like allocation

scheme; the number of elements in each set deeper in the stack can be

used to determine the address of a particular set's array. */

void

dfaanalyze (struct dfa *d, int searchflag)

{

int *nullable; /* Nullable stack. */

int *nfirstpos; /* Element count stack for firstpos sets. */

position *firstpos; /* Array where firstpos elements are stored. */

int *nlastpos; /* Element count stack for lastpos sets. */

position *lastpos; /* Array where lastpos elements are stored. */

int *nalloc; /* Sizes of arrays allocated to follow sets. */

position_set tmp; /* Temporary set for merging sets. */

position_set merged; /* Result of merging sets. */

int wants_newline; /* True if some position wants newline info. */

int *o_nullable;

int *o_nfirst, *o_nlast;

position *o_firstpos, *o_lastpos;

int i, j;

position *pos;

d->searchflag = searchflag;

MALLOC(nullable, int, d->depth);

o_nullable = nullable;

MALLOC(nfirstpos, int, d->depth);

o_nfirst = nfirstpos;

MALLOC(firstpos, position, d->nleaves);

o_firstpos = firstpos, firstpos += d->nleaves;

MALLOC(nlastpos, int, d->depth);

o_nlast = nlastpos;

MALLOC(lastpos, position, d->nleaves);

o_lastpos = lastpos, lastpos += d->nleaves;

MALLOC(nalloc, int, d->tindex);

for (i = 0; i < d->tindex; ++i)

nalloc[i] = 0;

MALLOC(merged.elems, position, d->nleaves);

CALLOC(d->follows, position_set, d->tindex);

for (i = 0; i < d->tindex; ++i)

switch (d->tokens[i])

{

case EMPTY:

/* The empty set is nullable. */

*nullable++ = 1;

/* The firstpos and lastpos of the empty leaf are both empty. */

*nfirstpos++ = *nlastpos++ = 0;

break;

case STAR:

case PLUS:

/* Every element in the firstpos of the argument is in the follow

of every element in the lastpos. */

tmp.nelem = nfirstpos[-1];

tmp.elems = firstpos;

pos = lastpos;

for (j = 0; j < nlastpos[-1]; ++j)

{

merge(&tmp, &d->follows[pos[j].index], &merged);

REALLOC_IF_NECESSARY(d->follows[pos[j].index].elems, position,

nalloc[pos[j].index], merged.nelem - 1);

copy(&merged, &d->follows[pos[j].index]);

}

case QMARK:

/* A QMARK or STAR node is automatically nullable. */

if (d->tokens[i] != PLUS)

nullable[-1] = 1;

break;

case CAT:

/* Every element in the firstpos of the second argument is in the

follow of every element in the lastpos of the first argument. */

tmp.nelem = nfirstpos[-1];

tmp.elems = firstpos;

pos = lastpos + nlastpos[-1];

for (j = 0; j < nlastpos[-2]; ++j)

{

merge(&tmp, &d->follows[pos[j].index], &merged);

REALLOC_IF_NECESSARY(d->follows[pos[j].index].elems, position,

nalloc[pos[j].index], merged.nelem - 1);

copy(&merged, &d->follows[pos[j].index]);

}

/* The firstpos of a CAT node is the firstpos of the first argument,

union that of the second argument if the first is nullable. */

if (nullable[-2])

nfirstpos[-2] += nfirstpos[-1];

else

firstpos += nfirstpos[-1];

--nfirstpos;

/* The lastpos of a CAT node is the lastpos of the second argument,

union that of the first argument if the second is nullable. */

if (nullable[-1])

nlastpos[-2] += nlastpos[-1];

else

{

pos = lastpos + nlastpos[-2];

for (j = nlastpos[-1] - 1; j >= 0; --j)

pos[j] = lastpos[j];

lastpos += nlastpos[-2];

nlastpos[-2] = nlastpos[-1];

}

--nlastpos;

/* A CAT node is nullable if both arguments are nullable. */

nullable[-2] = nullable[-1] && nullable[-2];

--nullable;

break;

case OR:

case ORTOP:

/* The firstpos is the union of the firstpos of each argument. */

nfirstpos[-2] += nfirstpos[-1];

--nfirstpos;

/* The lastpos is the union of the lastpos of each argument. */

nlastpos[-2] += nlastpos[-1];

--nlastpos;

/* An OR node is nullable if either argument is nullable. */

nullable[-2] = nullable[-1] || nullable[-2];

--nullable;

break;

default:

/* Anything else is a nonempty position. (Note that special

constructs like \< are treated as nonempty strings here;

an "epsilon closure" effectively makes them nullable later.

Backreferences have to get a real position so we can detect

transitions on them later. But they are nullable. */

*nullable++ = d->tokens[i] == BACKREF;

/* This position is in its own firstpos and lastpos. */

*nfirstpos++ = *nlastpos++ = 1;

--firstpos, --lastpos;

firstpos->index = lastpos->index = i;

firstpos->constraint = lastpos->constraint = NO_CONSTRAINT;

/* Allocate the follow set for this position. */

nalloc[i] = 1;

MALLOC(d->follows[i].elems, position, nalloc[i]);

break;

}

/* For each follow set that is the follow set of a real position, replace

it with its epsilon closure. */

for (i = 0; i < d->tindex; ++i)

if (d->tokens[i] < NOTCHAR || d->tokens[i] == BACKREF

|| d->tokens[i] >= CSET)

{

copy(&d->follows[i], &merged);

epsclosure(&merged, d);

if (d->follows[i].nelem < merged.nelem)

REALLOC(d->follows[i].elems, position, merged.nelem);

copy(&merged, &d->follows[i]);

}

/* Get the epsilon closure of the firstpos of the regexp. The result will

be the set of positions of state 0. */

merged.nelem = 0;

for (i = 0; i < nfirstpos[-1]; ++i)

insert(firstpos[i], &merged);

epsclosure(&merged, d);

/* Check if any of the positions of state 0 will want newline context. */

wants_newline = 0;

for (i = 0; i < merged.nelem; ++i)

if (PREV_NEWLINE_DEPENDENT(merged.elems[i].constraint))

wants_newline = 1;

/* Build the initial state. */

d->salloc = 1;

d->sindex = 0;

MALLOC(d->states, dfa_state, d->salloc);

state_index(d, &merged, wants_newline, 0);

free(o_nullable);

free(o_nfirst);

free(o_firstpos);

free(o_nlast);

free(o_lastpos);

free(nalloc);

free(merged.elems);

}

/* Find, for each character, the transition out of state s of d, and store

it in the appropriate slot of trans.

We divide the positions of s into groups (positions can appear in more

than one group). Each group is labeled with a set of characters that

every position in the group matches (taking into account, if necessary,

preceding context information of s). For each group, find the union

of the its elements' follows. This set is the set of positions of the

new state. For each character in the group's label, set the transition

on this character to be to a state corresponding to the set's positions,

and its associated backward context information, if necessary.

If we are building a searching matcher, we include the positions of state

0 in every state.

The collection of groups is constructed by building an equivalence-class

partition of the positions of s.

For each position, find the set of characters C that it matches. Eliminate

any characters from C that fail on grounds of backward context.

Search through the groups, looking for a group whose label L has nonempty

intersection with C. If L - C is nonempty, create a new group labeled

L - C and having the same positions as the current group, and set L to

the intersection of L and C. Insert the position in this group, set

C = C - L, and resume scanning.

If after comparing with every group there are characters remaining in C,

create a new group labeled with the characters of C and insert this

position in that group. */

void

dfastate (int s, struct dfa *d, int trans[])

{

position_set grps[NOTCHAR]; /* As many as will ever be needed. */

charclass labels[NOTCHAR]; /* Labels corresponding to the groups. */

int ngrps = 0; /* Number of groups actually used. */

position pos; /* Current position being considered. */

charclass matches; /* Set of matching characters. */

int matchesf; /* True if matches is nonempty. */

charclass intersect; /* Intersection with some label set. */

int intersectf; /* True if intersect is nonempty. */

charclass leftovers; /* Stuff in the label that didn't match. */

int leftoversf; /* True if leftovers is nonempty. */

static charclass letters; /* Set of characters considered letters. */

static charclass newline; /* Set of characters that aren't newline. */

position_set follows; /* Union of the follows of some group. */

position_set tmp; /* Temporary space for merging sets. */

int state; /* New state. */

int wants_newline; /* New state wants to know newline context. */

int state_newline; /* New state on a newline transition. */

int wants_letter; /* New state wants to know letter context. */

int state_letter; /* New state on a letter transition. */

static int initialized; /* Flag for static initialization. */

int i, j, k;

/* Initialize the set of letters, if necessary. */

if (! initialized)

{

initialized = 1;

for (i = 0; i < NOTCHAR; ++i)

if (IS_WORD_CONSTITUENT(i))

setbit(i, letters);

setbit(eolbyte, newline);

}

zeroset(matches);

for (i = 0; i < d->states[s].elems.nelem; ++i)

{

pos = d->states[s].elems.elems[i];

if (d->tokens[pos.index] >= 0 && d->tokens[pos.index] < NOTCHAR)

setbit(d->tokens[pos.index], matches);

else if (d->tokens[pos.index] >= CSET)

copyset(d->charclasses[d->tokens[pos.index] - CSET], matches);

else

continue;

/* Some characters may need to be eliminated from matches because

they fail in the current context. */

if (pos.constraint != 0xFF)

{

if (! MATCHES_NEWLINE_CONTEXT(pos.constraint,

d->states[s].newline, 1))

clrbit(eolbyte, matches);

if (! MATCHES_NEWLINE_CONTEXT(pos.constraint,

d->states[s].newline, 0))

for (j = 0; j < CHARCLASS_INTS; ++j)

matches[j] &= newline[j];

if (! MATCHES_LETTER_CONTEXT(pos.constraint,

d->states[s].letter, 1))

for (j = 0; j < CHARCLASS_INTS; ++j)

matches[j] &= ~letters[j];

if (! MATCHES_LETTER_CONTEXT(pos.constraint,

d->states[s].letter, 0))

for (j = 0; j < CHARCLASS_INTS; ++j)

matches[j] &= letters[j];

/* If there are no characters left, there's no point in going on. */

for (j = 0; j < CHARCLASS_INTS && !matches[j]; ++j)

continue;

if (j == CHARCLASS_INTS)

continue;

}

for (j = 0; j < ngrps; ++j)

{

/* If matches contains a single character only, and the current

group's label doesn't contain that character, go on to the

next group. */

if (d->tokens[pos.index] >= 0 && d->tokens[pos.index] < NOTCHAR

&& !tstbit(d->tokens[pos.index], labels[j]))

continue;

/* Check if this group's label has a nonempty intersection with

matches. */

intersectf = 0;

for (k = 0; k < CHARCLASS_INTS; ++k)

(intersect[k] = matches[k] & labels[j][k]) ? (intersectf = 1) : 0;

if (! intersectf)

continue;

/* It does; now find the set differences both ways. */

leftoversf = matchesf = 0;

for (k = 0; k < CHARCLASS_INTS; ++k)

{

/* Even an optimizing compiler can't know this for sure. */

int match = matches[k], label = labels[j][k];

(leftovers[k] = ~match & label) ? (leftoversf = 1) : 0;

(matches[k] = match & ~label) ? (matchesf = 1) : 0;

}

/* If there were leftovers, create a new group labeled with them. */

if (leftoversf)

{

copyset(leftovers, labels[ngrps]);

copyset(intersect, labels[j]);

MALLOC(grps[ngrps].elems, position, d->nleaves);

copy(&grps[j], &grps[ngrps]);

++ngrps;

}

/* Put the position in the current group. Note that there is no

reason to call insert() here. */

grps[j].elems[grps[j].nelem++] = pos;

/* If every character matching the current position has been

accounted for, we're done. */

if (! matchesf)

break;

}

/* If we've passed the last group, and there are still characters

unaccounted for, then we'll have to create a new group. */

if (j == ngrps)

{

copyset(matches, labels[ngrps]);

zeroset(matches);

MALLOC(grps[ngrps].elems, position, d->nleaves);

grps[ngrps].nelem = 1;

grps[ngrps].elems[0] = pos;

++ngrps;

}

}

MALLOC(follows.elems, position, d->nleaves);

MALLOC(tmp.elems, position, d->nleaves);

/* If we are a searching matcher, the default transition is to a state

containing the positions of state 0, otherwise the default transition

is to fail miserably. */

if (d->searchflag)

{

wants_newline = 0;

wants_letter = 0;

for (i = 0; i < d->states[0].elems.nelem; ++i)

{

if (PREV_NEWLINE_DEPENDENT(d->states[0].elems.elems[i].constraint))

wants_newline = 1;

if (PREV_LETTER_DEPENDENT(d->states[0].elems.elems[i].constraint))

wants_letter = 1;

}

copy(&d->states[0].elems, &follows);

state = state_index(d, &follows, 0, 0);

if (wants_newline)

state_newline = state_index(d, &follows, 1, 0);

else

state_newline = state;

if (wants_letter)

state_letter = state_index(d, &follows, 0, 1);

else

state_letter = state;

for (i = 0; i < NOTCHAR; ++i)

trans[i] = (IS_WORD_CONSTITUENT(i)) ? state_letter : state;

trans[eolbyte] = state_newline;

}

else

for (i = 0; i < NOTCHAR; ++i)

trans[i] = -1;

for (i = 0; i < ngrps; ++i)

{

follows.nelem = 0;

/* Find the union of the follows of the positions of the group.

This is a hideously inefficient loop. Fix it someday. */

for (j = 0; j < grps[i].nelem; ++j)

for (k = 0; k < d->follows[grps[i].elems[j].index].nelem; ++k)

insert(d->follows[grps[i].elems[j].index].elems[k], &follows);

/* If we are building a searching matcher, throw in the positions

of state 0 as well. */

if (d->searchflag)

for (j = 0; j < d->states[0].elems.nelem; ++j)

insert(d->states[0].elems.elems[j], &follows);

/* Find out if the new state will want any context information. */

wants_newline = 0;

if (tstbit(eolbyte, labels[i]))

for (j = 0; j < follows.nelem; ++j)

if (PREV_NEWLINE_DEPENDENT(follows.elems[j].constraint))

wants_newline = 1;

wants_letter = 0;

for (j = 0; j < CHARCLASS_INTS; ++j)

if (labels[i][j] & letters[j])

break;

if (j < CHARCLASS_INTS)

for (j = 0; j < follows.nelem; ++j)

if (PREV_LETTER_DEPENDENT(follows.elems[j].constraint))

wants_letter = 1;

/* Find the state(s) corresponding to the union of the follows. */

state = state_index(d, &follows, 0, 0);

if (wants_newline)

state_newline = state_index(d, &follows, 1, 0);

else

state_newline = state;

if (wants_letter)

state_letter = state_index(d, &follows, 0, 1);

else

state_letter = state;

/* Set the transitions for each character in the current label. */

for (j = 0; j < CHARCLASS_INTS; ++j)

for (k = 0; k < INTBITS; ++k)

if (labels[i][j] & 1 << k)

{

int c = j * INTBITS + k;

if (c == eolbyte)

trans[c] = state_newline;

else if (IS_WORD_CONSTITUENT(c))

trans[c] = state_letter;

else if (c < NOTCHAR)

trans[c] = state;

}

}

for (i = 0; i < ngrps; ++i)

free(grps[i].elems);

free(follows.elems);

free(tmp.elems);

}

/* Some routines for manipulating a compiled dfa's transition tables.

Each state may or may not have a transition table; if it does, and it

is a non-accepting state, then d->trans[state] points to its table.

If it is an accepting state then d->fails[state] points to its table.

If it has no table at all, then d->trans[state] is NULL.

TODO: Improve this comment, get rid of the unnecessary redundancy. */

static void

build_state (int s, struct dfa *d)

{

int *trans; /* The new transition table. */

int i;

/* Set an upper limit on the number of transition tables that will ever

exist at once. 1024 is arbitrary. The idea is that the frequently

used transition tables will be quickly rebuilt, whereas the ones that

were only needed once or twice will be cleared away. */

if (d->trcount >= 1024)

{

for (i = 0; i < d->tralloc; ++i)

if (d->trans[i])

{

free((ptr_t) d->trans[i]);

d->trans[i] = NULL;

}

else if (d->fails[i])

{

free((ptr_t) d->fails[i]);

d->fails[i] = NULL;

}

d->trcount = 0;

}

++d->trcount;

/* Set up the success bits for this state. */

d->success[s] = 0;

if (ACCEPTS_IN_CONTEXT(d->states[s].newline, 1, d->states[s].letter, 0,

s, *d))

d->success[s] |= 4;

if (ACCEPTS_IN_CONTEXT(d->states[s].newline, 0, d->states[s].letter, 1,

s, *d))

d->success[s] |= 2;

if (ACCEPTS_IN_CONTEXT(d->states[s].newline, 0, d->states[s].letter, 0,

s, *d))

d->success[s] |= 1;

MALLOC(trans, int, NOTCHAR);

dfastate(s, d, trans);

/* Now go through the new transition table, and make sure that the trans

and fail arrays are allocated large enough to hold a pointer for the

largest state mentioned in the table. */

for (i = 0; i < NOTCHAR; ++i)

if (trans[i] >= d->tralloc)

{

int oldalloc = d->tralloc;

while (trans[i] >= d->tralloc)

d->tralloc *= 2;

REALLOC(d->realtrans, int *, d->tralloc + 1);

d->trans = d->realtrans + 1;

REALLOC(d->fails, int *, d->tralloc);

REALLOC(d->success, int, d->tralloc);

while (oldalloc < d->tralloc)

{

d->trans[oldalloc] = NULL;

d->fails[oldalloc++] = NULL;

}

}

/* Newline is a sentinel. */

trans[eolbyte] = -1;

if (ACCEPTING(s, *d))

d->fails[s] = trans;

else

d->trans[s] = trans;

}

static void

build_state_zero (struct dfa *d)

{

d->tralloc = 1;

d->trcount = 0;

CALLOC(d->realtrans, int *, d->tralloc + 1);

d->trans = d->realtrans + 1;

CALLOC(d->fails, int *, d->tralloc);

MALLOC(d->success, int, d->tralloc);

build_state(0, d);

}

/* Search through a buffer looking for a match to the given struct dfa.

Find the first occurrence of a string matching the regexp in the buffer,

and the shortest possible version thereof. Return the offset of the first

character after the match, or (size_t) -1 if none is found. BEGIN points to

the beginning of the buffer, and SIZE is the size of the buffer. If SIZE

is nonzero, BEGIN[SIZE - 1] must be a newline. BACKREF points to a place

where we're supposed to store a 1 if backreferencing happened and the

match needs to be verified by a backtracking matcher. Otherwise

we store a 0 in *backref. */

size_t

dfaexec (struct dfa *d, char const *begin, size_t size, int *backref)

{

register int s; /* Current state. */

register unsigned char const *p; /* Current input character. */

register unsigned char const *end; /* One past the last input character. */

register int **trans, *t; /* Copy of d->trans so it can be optimized

into a register. */

register unsigned char eol = eolbyte; /* Likewise for eolbyte. */

static int sbit[NOTCHAR]; /* Table for anding with d->success. */

static int sbit_init;

if (! sbit_init)

{

int i;

sbit_init = 1;

for (i = 0; i < NOTCHAR; ++i)

sbit[i] = (IS_WORD_CONSTITUENT(i)) ? 2 : 1;

sbit[eol] = 4;

}

if (! d->tralloc)

build_state_zero(d);

s = 0;

p = (unsigned char const *) begin;

end = p + size;

trans = d->trans;

for (;;)

{

while ((t = trans[s]))

s = t[*p++];

if (s < 0)

{

if (p == end)

{

return (size_t) -1;

}

s = 0;

}

else if ((t = d->fails[s]))

{

if (d->success[s] & sbit[*p])

{

if (backref)

*backref = (d->states[s].backref != 0);

return (char const *) p - begin;

}

s = t[*p++];

}

else

{

build_state(s, d);

trans = d->trans;

}

}

}

/* Initialize the components of a dfa that the other routines don't

initialize for themselves. */

void

dfainit (struct dfa *d)

{

d->calloc = 1;

MALLOC(d->charclasses, charclass, d->calloc);

d->cindex = 0;

d->talloc = 1;

MALLOC(d->tokens, token, d->talloc);

d->tindex = d->depth = d->nleaves = d->nregexps = 0;

d->searchflag = 0;

d->tralloc = 0;

d->musts = 0;

}

/* Parse and analyze a single string of the given length. */

void

dfacomp (char const *s, size_t len, struct dfa *d, int searchflag)

{

if (case_fold) /* dummy folding in service of dfamust() */

{

char *lcopy;

int i;

lcopy = (char*)malloc(len,i);

//lcopy = new char[len];

if (!lcopy) dfaerror(_("memory exhausted"));

/* This is a kludge. */

case_fold = 0;

for (i = 0; i < len; ++i)

if (ISUPPER ((unsigned char) s[i]))

lcopy[i] = tolower ((unsigned char) s[i]);

else

lcopy[i] = s[i];

dfainit(d);

dfaparse(lcopy, len, d);

free(lcopy);

dfamust(d);

d->cindex = d->tindex = d->depth = d->nleaves = d->nregexps = 0;

case_fold = 1;

dfaparse(s, len, d);

dfaanalyze(d, searchflag);

}

else

{

dfainit(d);

dfaparse(s, len, d);

dfamust(d);

dfaanalyze(d, searchflag);

}

}

"Brian Muth" <bmuth@mvps.org> wrote in message
news:uYw2N0IcJHA.1184@TK2MSFTNGP05.phx.gbl...