3621 lines
96 KiB
C
3621 lines
96 KiB
C
/* dfa.c - deterministic extended regexp routines for GNU
|
|
Copyright 1988, 1998, 2000 Free Software Foundation, Inc.
|
|
|
|
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, 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 */
|
|
|
|
/* Written June, 1988 by Mike Haertel
|
|
Modified July, 1988 by Arthur David Olson to assist BMG speedups */
|
|
|
|
/* $FreeBSD$ */
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include <config.h>
|
|
#endif
|
|
|
|
#include <assert.h>
|
|
#include <ctype.h>
|
|
#include <stdio.h>
|
|
|
|
#include <sys/types.h>
|
|
#ifdef STDC_HEADERS
|
|
#include <stdlib.h>
|
|
#else
|
|
extern char *calloc(), *malloc(), *realloc();
|
|
extern void free();
|
|
#endif
|
|
|
|
#if defined(HAVE_STRING_H) || defined(STDC_HEADERS)
|
|
#include <string.h>
|
|
#else
|
|
#include <strings.h>
|
|
#endif
|
|
|
|
#if HAVE_SETLOCALE
|
|
# include <locale.h>
|
|
#endif
|
|
|
|
#if defined HAVE_WCTYPE_H && defined HAVE_WCHAR_H && defined HAVE_MBRTOWC
|
|
/* We can handle multibyte string. */
|
|
# define MBS_SUPPORT
|
|
#endif
|
|
|
|
#ifdef MBS_SUPPORT
|
|
# include <wchar.h>
|
|
# include <wctype.h>
|
|
#endif
|
|
|
|
#ifndef DEBUG /* use the same approach as regex.c */
|
|
#undef assert
|
|
#define assert(e)
|
|
#endif /* DEBUG */
|
|
|
|
#ifndef isgraph
|
|
#define isgraph(C) (isprint(C) && !isspace(C))
|
|
#endif
|
|
|
|
#if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
|
|
#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)
|
|
#else
|
|
#define ISALPHA(C) (isascii(C) && isalpha(C))
|
|
#define ISUPPER(C) (isascii(C) && isupper(C))
|
|
#define ISLOWER(C) (isascii(C) && islower(C))
|
|
#define ISDIGIT(C) (isascii(C) && isdigit(C))
|
|
#define ISXDIGIT(C) (isascii(C) && isxdigit(C))
|
|
#define ISSPACE(C) (isascii(C) && isspace(C))
|
|
#define ISPUNCT(C) (isascii(C) && ispunct(C))
|
|
#define ISALNUM(C) (isascii(C) && isalnum(C))
|
|
#define ISPRINT(C) (isascii(C) && isprint(C))
|
|
#define ISGRAPH(C) (isascii(C) && isgraph(C))
|
|
#define ISCNTRL(C) (isascii(C) && iscntrl(C))
|
|
#endif
|
|
|
|
/* 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)
|
|
|
|
/* If we (don't) have I18N. */
|
|
/* glibc defines _ */
|
|
#ifndef _
|
|
# ifdef HAVE_LIBINTL_H
|
|
# include <libintl.h>
|
|
# ifndef _
|
|
# define _(Str) gettext (Str)
|
|
# endif
|
|
# else
|
|
# define _(Str) (Str)
|
|
# endif
|
|
#endif
|
|
|
|
#include "regex.h"
|
|
#include "dfa.h"
|
|
#include "hard-locale.h"
|
|
|
|
/* HPUX, define those as macros in sys/param.h */
|
|
#ifdef setbit
|
|
# undef setbit
|
|
#endif
|
|
#ifdef clrbit
|
|
# undef clrbit
|
|
#endif
|
|
|
|
static void dfamust PARAMS ((struct dfa *dfa));
|
|
static void regexp PARAMS ((int toplevel));
|
|
|
|
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); \
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
|
|
static void
|
|
prtok (token t)
|
|
{
|
|
char const *s;
|
|
|
|
if (t < 0)
|
|
fprintf(stderr, "END");
|
|
else if (t < NOTCHAR)
|
|
fprintf(stderr, "%c", t);
|
|
else
|
|
{
|
|
switch (t)
|
|
{
|
|
case EMPTY: s = "EMPTY"; break;
|
|
case BACKREF: s = "BACKREF"; break;
|
|
case BEGLINE: s = "BEGLINE"; break;
|
|
case ENDLINE: s = "ENDLINE"; break;
|
|
case BEGWORD: s = "BEGWORD"; break;
|
|
case ENDWORD: s = "ENDWORD"; break;
|
|
case LIMWORD: s = "LIMWORD"; break;
|
|
case NOTLIMWORD: s = "NOTLIMWORD"; break;
|
|
case QMARK: s = "QMARK"; break;
|
|
case STAR: s = "STAR"; break;
|
|
case PLUS: s = "PLUS"; break;
|
|
case CAT: s = "CAT"; break;
|
|
case OR: s = "OR"; break;
|
|
case ORTOP: s = "ORTOP"; break;
|
|
case LPAREN: s = "LPAREN"; break;
|
|
case RPAREN: s = "RPAREN"; break;
|
|
case CRANGE: s = "CRANGE"; break;
|
|
#ifdef MBS_SUPPORT
|
|
case ANYCHAR: s = "ANYCHAR"; break;
|
|
case MBCSET: s = "MBCSET"; break;
|
|
#endif /* MBS_SUPPORT */
|
|
default: s = "CSET"; break;
|
|
}
|
|
fprintf(stderr, "%s", s);
|
|
}
|
|
}
|
|
#endif /* DEBUG */
|
|
|
|
/* 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 *lexstart; /* Pointer to beginning of input string. */
|
|
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. */
|
|
|
|
#ifdef MBS_SUPPORT
|
|
/* These variables are used only if (MB_CUR_MAX > 1). */
|
|
static mbstate_t mbs; /* Mbstate for mbrlen(). */
|
|
static int cur_mb_len; /* Byte length of the current scanning
|
|
multibyte character. */
|
|
static int cur_mb_index; /* Byte index of the current scanning multibyte
|
|
character.
|
|
|
|
singlebyte character : cur_mb_index = 0
|
|
multibyte character
|
|
1st byte : cur_mb_index = 1
|
|
2nd byte : cur_mb_index = 2
|
|
...
|
|
nth byte : cur_mb_index = n */
|
|
static unsigned char *mblen_buf;/* Correspond to the input buffer in dfaexec().
|
|
Each element store the amount of remain
|
|
byte of corresponding multibyte character
|
|
in the input string. A element's value
|
|
is 0 if corresponding character is a
|
|
singlebyte chracter.
|
|
e.g. input : 'a', <mb(0)>, <mb(1)>, <mb(2)>
|
|
mblen_buf : 0, 3, 2, 1
|
|
*/
|
|
static wchar_t *inputwcs; /* Wide character representation of input
|
|
string in dfaexec().
|
|
The length of this array is same as
|
|
the length of input string(char array).
|
|
inputstring[i] is a single-byte char,
|
|
or 1st byte of a multibyte char.
|
|
And inputwcs[i] is the codepoint. */
|
|
static unsigned char const *buf_begin;/* refference to begin in dfaexec(). */
|
|
static unsigned char const *buf_end; /* refference to end in dfaexec(). */
|
|
#endif /* MBS_SUPPORT */
|
|
|
|
#ifdef MBS_SUPPORT
|
|
/* This function update cur_mb_len, and cur_mb_index.
|
|
p points current lexptr, len is the remaining buffer length. */
|
|
static void
|
|
update_mb_len_index (unsigned char const *p, int len)
|
|
{
|
|
/* If last character is a part of a multibyte character,
|
|
we update cur_mb_index. */
|
|
if (cur_mb_index)
|
|
cur_mb_index = (cur_mb_index >= cur_mb_len)? 0
|
|
: cur_mb_index + 1;
|
|
|
|
/* If last character is a single byte character, or the
|
|
last portion of a multibyte character, we check whether
|
|
next character is a multibyte character or not. */
|
|
if (! cur_mb_index)
|
|
{
|
|
cur_mb_len = mbrlen(p, len, &mbs);
|
|
if (cur_mb_len > 1)
|
|
/* It is a multibyte character.
|
|
cur_mb_len was already set by mbrlen(). */
|
|
cur_mb_index = 1;
|
|
else if (cur_mb_len < 1)
|
|
/* Invalid sequence. We treat it as a singlebyte character.
|
|
cur_mb_index is aleady 0. */
|
|
cur_mb_len = 1;
|
|
/* Otherwise, cur_mb_len == 1, it is a singlebyte character.
|
|
cur_mb_index is aleady 0. */
|
|
}
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
|
|
#ifdef MBS_SUPPORT
|
|
/* Note that characters become unsigned here. */
|
|
# define FETCH(c, eoferr) \
|
|
{ \
|
|
if (! lexleft) \
|
|
{ \
|
|
if (eoferr != 0) \
|
|
dfaerror (eoferr); \
|
|
else \
|
|
return lasttok = END; \
|
|
} \
|
|
if (MB_CUR_MAX > 1) \
|
|
update_mb_len_index(lexptr, lexleft); \
|
|
(c) = (unsigned char) *lexptr++; \
|
|
--lexleft; \
|
|
}
|
|
|
|
/* This function fetch a wide character, and update cur_mb_len,
|
|
used only if the current locale is a multibyte environment. */
|
|
static wint_t
|
|
fetch_wc (char const *eoferr)
|
|
{
|
|
wchar_t wc;
|
|
if (! lexleft)
|
|
{
|
|
if (eoferr != 0)
|
|
dfaerror (eoferr);
|
|
else
|
|
return WEOF;
|
|
}
|
|
|
|
cur_mb_len = mbrtowc(&wc, lexptr, lexleft, &mbs);
|
|
if (cur_mb_len <= 0)
|
|
{
|
|
cur_mb_len = 1;
|
|
wc = *lexptr;
|
|
}
|
|
lexptr += cur_mb_len;
|
|
lexleft -= cur_mb_len;
|
|
return wc;
|
|
}
|
|
#else
|
|
/* 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; \
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
|
|
#ifdef MBS_SUPPORT
|
|
/* Multibyte character handling sub-routin for lex.
|
|
This function parse a bracket expression and build a struct
|
|
mb_char_classes. */
|
|
static void
|
|
parse_bracket_exp_mb ()
|
|
{
|
|
wint_t wc, wc1, wc2;
|
|
|
|
/* Work area to build a mb_char_classes. */
|
|
struct mb_char_classes *work_mbc;
|
|
int chars_al, range_sts_al, range_ends_al, ch_classes_al,
|
|
equivs_al, coll_elems_al;
|
|
|
|
REALLOC_IF_NECESSARY(dfa->mbcsets, struct mb_char_classes,
|
|
dfa->mbcsets_alloc, dfa->nmbcsets + 1);
|
|
/* dfa->multibyte_prop[] hold the index of dfa->mbcsets.
|
|
We will update dfa->multibyte_prop in addtok(), because we can't
|
|
decide the index in dfa->tokens[]. */
|
|
|
|
/* Initialize work are */
|
|
work_mbc = &(dfa->mbcsets[dfa->nmbcsets++]);
|
|
|
|
chars_al = 1;
|
|
range_sts_al = range_ends_al = 0;
|
|
ch_classes_al = equivs_al = coll_elems_al = 0;
|
|
MALLOC(work_mbc->chars, wchar_t, chars_al);
|
|
|
|
work_mbc->nchars = work_mbc->nranges = work_mbc->nch_classes = 0;
|
|
work_mbc->nequivs = work_mbc->ncoll_elems = 0;
|
|
work_mbc->chars = work_mbc->ch_classes = NULL;
|
|
work_mbc->range_sts = work_mbc->range_ends = NULL;
|
|
work_mbc->equivs = work_mbc->coll_elems = NULL;
|
|
|
|
wc = fetch_wc(_("Unbalanced ["));
|
|
if (wc == L'^')
|
|
{
|
|
wc = fetch_wc(_("Unbalanced ["));
|
|
work_mbc->invert = 1;
|
|
}
|
|
else
|
|
work_mbc->invert = 0;
|
|
do
|
|
{
|
|
wc1 = WEOF; /* mark wc1 is not initialized". */
|
|
|
|
/* 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 (wc == L'[' && (syntax_bits & RE_CHAR_CLASSES))
|
|
{
|
|
#define BRACKET_BUFFER_SIZE 128
|
|
char str[BRACKET_BUFFER_SIZE];
|
|
wc1 = wc;
|
|
wc = fetch_wc(_("Unbalanced ["));
|
|
|
|
/* If pattern contains `[[:', `[[.', or `[[='. */
|
|
if (cur_mb_len == 1 && (wc == L':' || wc == L'.' || wc == L'='))
|
|
{
|
|
unsigned char c;
|
|
unsigned char delim = (unsigned char)wc;
|
|
int len = 0;
|
|
for (;;)
|
|
{
|
|
if (! lexleft)
|
|
dfaerror (_("Unbalanced ["));
|
|
c = (unsigned char) *lexptr++;
|
|
--lexleft;
|
|
|
|
if ((c == delim && *lexptr == ']') || lexleft == 0)
|
|
break;
|
|
if (len < BRACKET_BUFFER_SIZE)
|
|
str[len++] = c;
|
|
else
|
|
/* This is in any case an invalid class name. */
|
|
str[0] = '\0';
|
|
}
|
|
str[len] = '\0';
|
|
|
|
if (lexleft == 0)
|
|
{
|
|
REALLOC_IF_NECESSARY(work_mbc->chars, wchar_t, chars_al,
|
|
work_mbc->nchars + 2);
|
|
work_mbc->chars[work_mbc->nchars++] = L'[';
|
|
work_mbc->chars[work_mbc->nchars++] = delim;
|
|
break;
|
|
}
|
|
|
|
if (--lexleft, *lexptr++ != ']')
|
|
dfaerror (_("Unbalanced ["));
|
|
if (delim == ':')
|
|
/* build character class. */
|
|
{
|
|
wctype_t wt;
|
|
/* Query the character class as wctype_t. */
|
|
wt = wctype (str);
|
|
|
|
if (ch_classes_al == 0)
|
|
MALLOC(work_mbc->ch_classes, wchar_t, ++ch_classes_al);
|
|
REALLOC_IF_NECESSARY(work_mbc->ch_classes, wctype_t,
|
|
ch_classes_al,
|
|
work_mbc->nch_classes + 1);
|
|
work_mbc->ch_classes[work_mbc->nch_classes++] = wt;
|
|
|
|
}
|
|
else if (delim == '=' || delim == '.')
|
|
{
|
|
char *elem;
|
|
MALLOC(elem, char, len + 1);
|
|
strncpy(elem, str, len + 1);
|
|
|
|
if (delim == '=')
|
|
/* build equivalent class. */
|
|
{
|
|
if (equivs_al == 0)
|
|
MALLOC(work_mbc->equivs, char*, ++equivs_al);
|
|
REALLOC_IF_NECESSARY(work_mbc->equivs, char*,
|
|
equivs_al,
|
|
work_mbc->nequivs + 1);
|
|
work_mbc->equivs[work_mbc->nequivs++] = elem;
|
|
}
|
|
|
|
if (delim == '.')
|
|
/* build collating element. */
|
|
{
|
|
if (coll_elems_al == 0)
|
|
MALLOC(work_mbc->coll_elems, char*, ++coll_elems_al);
|
|
REALLOC_IF_NECESSARY(work_mbc->coll_elems, char*,
|
|
coll_elems_al,
|
|
work_mbc->ncoll_elems + 1);
|
|
work_mbc->coll_elems[work_mbc->ncoll_elems++] = elem;
|
|
}
|
|
}
|
|
wc1 = wc = WEOF;
|
|
}
|
|
else
|
|
/* We treat '[' as a normal character here. */
|
|
{
|
|
wc2 = wc1; wc1 = wc; wc = wc2; /* swap */
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (wc == L'\\' && (syntax_bits & RE_BACKSLASH_ESCAPE_IN_LISTS))
|
|
wc = fetch_wc(("Unbalanced ["));
|
|
}
|
|
|
|
if (wc1 == WEOF)
|
|
wc1 = fetch_wc(_("Unbalanced ["));
|
|
|
|
if (wc1 == L'-')
|
|
/* build range characters. */
|
|
{
|
|
wc2 = fetch_wc(_("Unbalanced ["));
|
|
if (wc2 == L']')
|
|
{
|
|
/* In the case [x-], the - is an ordinary hyphen,
|
|
which is left in c1, the lookahead character. */
|
|
lexptr -= cur_mb_len;
|
|
lexleft += cur_mb_len;
|
|
wc2 = wc;
|
|
}
|
|
else
|
|
{
|
|
if (wc2 == L'\\'
|
|
&& (syntax_bits & RE_BACKSLASH_ESCAPE_IN_LISTS))
|
|
wc2 = fetch_wc(_("Unbalanced ["));
|
|
wc1 = fetch_wc(_("Unbalanced ["));
|
|
}
|
|
|
|
if (range_sts_al == 0)
|
|
{
|
|
MALLOC(work_mbc->range_sts, wchar_t, ++range_sts_al);
|
|
MALLOC(work_mbc->range_ends, wchar_t, ++range_ends_al);
|
|
}
|
|
REALLOC_IF_NECESSARY(work_mbc->range_sts, wchar_t,
|
|
range_sts_al, work_mbc->nranges + 1);
|
|
work_mbc->range_sts[work_mbc->nranges] = (wchar_t)wc;
|
|
REALLOC_IF_NECESSARY(work_mbc->range_ends, wchar_t,
|
|
range_ends_al, work_mbc->nranges + 1);
|
|
work_mbc->range_ends[work_mbc->nranges++] = (wchar_t)wc2;
|
|
}
|
|
else if (wc != WEOF)
|
|
/* build normal characters. */
|
|
{
|
|
REALLOC_IF_NECESSARY(work_mbc->chars, wchar_t, chars_al,
|
|
work_mbc->nchars + 1);
|
|
work_mbc->chars[work_mbc->nchars++] = (wchar_t)wc;
|
|
}
|
|
}
|
|
while ((wc = wc1) != L']');
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
|
|
#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);
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1 && cur_mb_index)
|
|
/* If this is a part of a multi-byte character, we must treat
|
|
this byte data as a normal character.
|
|
e.g. In case of SJIS encoding, some character contains '\',
|
|
but they must not be backslash. */
|
|
goto normal_char;
|
|
#endif /* MBS_SUPPORT */
|
|
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;
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
/* In multibyte environment period must match with a single
|
|
character not a byte. So we use ANYCHAR. */
|
|
laststart = 0;
|
|
return lasttok = ANYCHAR;
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
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 = 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 = CSET + charclass_index(ccl);
|
|
|
|
case '[':
|
|
if (backslash)
|
|
goto normal_char;
|
|
laststart = 0;
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
/* In multibyte environment a bracket expression may contain
|
|
multibyte characters, which must be treated as characters
|
|
(not bytes). So we parse it by parse_bracket_exp_mb(). */
|
|
parse_bracket_exp_mb();
|
|
return lasttok = MBCSET;
|
|
}
|
|
#endif
|
|
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 */
|
|
char expr[6] = { '[', c, '-', c2, ']', '\0' };
|
|
regex_t re;
|
|
if (regcomp (&re, expr, case_fold ? REG_ICASE : 0) == REG_NOERROR) {
|
|
for (c = 0; c < NOTCHAR; ++c) {
|
|
char buf[2] = { c, '\0' };
|
|
regmatch_t mat;
|
|
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 = CSET + charclass_index(ccl);
|
|
|
|
default:
|
|
normal_char:
|
|
laststart = 0;
|
|
if (case_fold && ISALPHA(c))
|
|
{
|
|
zeroset(ccl);
|
|
setbit_case_fold (c, ccl);
|
|
return lasttok = CSET + charclass_index(ccl);
|
|
}
|
|
return 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)
|
|
{
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
REALLOC_IF_NECESSARY(dfa->multibyte_prop, int, dfa->nmultibyte_prop,
|
|
dfa->tindex);
|
|
/* Set dfa->multibyte_prop. See struct dfa in dfa.h. */
|
|
if (t == MBCSET)
|
|
dfa->multibyte_prop[dfa->tindex] = ((dfa->nmbcsets - 1) << 2) + 3;
|
|
else if (t < NOTCHAR)
|
|
dfa->multibyte_prop[dfa->tindex]
|
|
= (cur_mb_len == 1)? 3 /* single-byte char */
|
|
: (((cur_mb_index == 1)? 1 : 0) /* 1st-byte of multibyte char */
|
|
+ ((cur_mb_index == cur_mb_len)? 2 : 0)); /* last-byte */
|
|
else
|
|
/* It may be unnecesssary, but it is safer to treat other
|
|
symbols as singlebyte characters. */
|
|
dfa->multibyte_prop[dfa->tindex] = 3;
|
|
}
|
|
#endif
|
|
|
|
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
|
|
#ifdef MBS_SUPPORT
|
|
|| tok == ANYCHAR || tok == MBCSET /* MB_CUR_MAX > 1 */
|
|
#endif /* MBS_SUPPORT */
|
|
|| tok == ENDWORD || tok == LIMWORD || tok == NOTLIMWORD)
|
|
{
|
|
addtok(tok);
|
|
tok = lex();
|
|
#ifdef MBS_SUPPORT
|
|
/* We treat a multibyte character as a single atom, so that DFA
|
|
can treat a multibyte character as a single expression.
|
|
|
|
e.g. We construct following tree from "<mb1><mb2>".
|
|
<mb1(1st-byte)><mb1(2nd-byte)><CAT><mb1(3rd-byte)><CAT>
|
|
<mb2(1st-byte)><mb2(2nd-byte)><CAT><mb2(3rd-byte)><CAT><CAT>
|
|
*/
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
while (cur_mb_index > 1 && tok >= 0 && tok < NOTCHAR)
|
|
{
|
|
addtok(tok);
|
|
addtok(CAT);
|
|
tok = lex();
|
|
}
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
}
|
|
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 (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;
|
|
lexstart = lexptr = s;
|
|
lexleft = len;
|
|
lasttok = END;
|
|
laststart = 1;
|
|
parens = 0;
|
|
hard_LC_COLLATE = hard_locale (LC_COLLATE);
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
cur_mb_index = 0;
|
|
cur_mb_len = 0;
|
|
memset(&mbs, 0, sizeof(mbstate_t));
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
|
|
if (! syntax_bits_set)
|
|
dfaerror(_("No syntax specified"));
|
|
|
|
tok = lex();
|
|
depth = d->depth;
|
|
|
|
regexp(1);
|
|
|
|
if (tok != END)
|
|
dfaerror(_("Unbalanced )"));
|
|
|
|
addtok(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;
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
d->states[i].mbps.nelem = 0;
|
|
#endif
|
|
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
|
|
#ifdef MBS_SUPPORT
|
|
&& d->tokens[s->elems[i].index] != ANYCHAR
|
|
&& d->tokens[s->elems[i].index] != MBCSET
|
|
#endif
|
|
&& 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;
|
|
|
|
#ifdef DEBUG
|
|
fprintf(stderr, "dfaanalyze:\n");
|
|
for (i = 0; i < d->tindex; ++i)
|
|
{
|
|
fprintf(stderr, " %d:", i);
|
|
prtok(d->tokens[i]);
|
|
}
|
|
putc('\n', stderr);
|
|
#endif
|
|
|
|
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)
|
|
#ifdef DEBUG
|
|
{ /* Nonsyntactic #ifdef goo... */
|
|
#endif
|
|
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;
|
|
}
|
|
#ifdef DEBUG
|
|
/* ... balance the above nonsyntactic #ifdef goo... */
|
|
fprintf(stderr, "node %d:", i);
|
|
prtok(d->tokens[i]);
|
|
putc('\n', stderr);
|
|
fprintf(stderr, nullable[-1] ? " nullable: yes\n" : " nullable: no\n");
|
|
fprintf(stderr, " firstpos:");
|
|
for (j = nfirstpos[-1] - 1; j >= 0; --j)
|
|
{
|
|
fprintf(stderr, " %d:", firstpos[j].index);
|
|
prtok(d->tokens[firstpos[j].index]);
|
|
}
|
|
fprintf(stderr, "\n lastpos:");
|
|
for (j = nlastpos[-1] - 1; j >= 0; --j)
|
|
{
|
|
fprintf(stderr, " %d:", lastpos[j].index);
|
|
prtok(d->tokens[lastpos[j].index]);
|
|
}
|
|
putc('\n', stderr);
|
|
}
|
|
#endif
|
|
|
|
/* 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
|
|
#ifdef MBS_SUPPORT
|
|
|| d->tokens[i] == ANYCHAR
|
|
|| d->tokens[i] == MBCSET
|
|
#endif
|
|
|| d->tokens[i] >= CSET)
|
|
{
|
|
#ifdef DEBUG
|
|
fprintf(stderr, "follows(%d:", i);
|
|
prtok(d->tokens[i]);
|
|
fprintf(stderr, "):");
|
|
for (j = d->follows[i].nelem - 1; j >= 0; --j)
|
|
{
|
|
fprintf(stderr, " %d:", d->follows[i].elems[j].index);
|
|
prtok(d->tokens[d->follows[i].elems[j].index]);
|
|
}
|
|
putc('\n', stderr);
|
|
#endif
|
|
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. */
|
|
#ifdef MBS_SUPPORT
|
|
int next_isnt_1st_byte = 0; /* Flag If we can't add state0. */
|
|
#endif
|
|
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);
|
|
#ifdef MBS_SUPPORT
|
|
else if (d->tokens[pos.index] == ANYCHAR
|
|
|| d->tokens[pos.index] == MBCSET)
|
|
/* MB_CUR_MAX > 1 */
|
|
{
|
|
/* ANYCHAR and MBCSET must match with a single character, so we
|
|
must put it to d->states[s].mbps, which contains the positions
|
|
which can match with a single character not a byte. */
|
|
if (d->states[s].mbps.nelem == 0)
|
|
{
|
|
MALLOC(d->states[s].mbps.elems, position,
|
|
d->states[s].elems.nelem);
|
|
}
|
|
insert(pos, &(d->states[s].mbps));
|
|
continue;
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
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);
|
|
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
/* If a token in follows.elems is not 1st byte of a multibyte
|
|
character, or the states of follows must accept the bytes
|
|
which are not 1st byte of the multibyte character.
|
|
Then, if a state of follows encounter a byte, it must not be
|
|
a 1st byte of a multibyte character nor singlebyte character.
|
|
We cansel to add state[0].follows to next state, because
|
|
state[0] must accept 1st-byte
|
|
|
|
For example, we assume <sb a> is a certain singlebyte
|
|
character, <mb A> is a certain multibyte character, and the
|
|
codepoint of <sb a> equals the 2nd byte of the codepoint of
|
|
<mb A>.
|
|
When state[0] accepts <sb a>, state[i] transit to state[i+1]
|
|
by accepting accepts 1st byte of <mb A>, and state[i+1]
|
|
accepts 2nd byte of <mb A>, if state[i+1] encounter the
|
|
codepoint of <sb a>, it must not be <sb a> but 2nd byte of
|
|
<mb A>, so we can not add state[0]. */
|
|
|
|
next_isnt_1st_byte = 0;
|
|
for (j = 0; j < follows.nelem; ++j)
|
|
{
|
|
if (!(d->multibyte_prop[follows.elems[j].index] & 1))
|
|
{
|
|
next_isnt_1st_byte = 1;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* If we are building a searching matcher, throw in the positions
|
|
of state 0 as well. */
|
|
#ifdef MBS_SUPPORT
|
|
if (d->searchflag && (MB_CUR_MAX == 1 || !next_isnt_1st_byte))
|
|
#else
|
|
if (d->searchflag)
|
|
#endif
|
|
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);
|
|
}
|
|
|
|
#ifdef MBS_SUPPORT
|
|
/* Multibyte character handling sub-routins for dfaexec. */
|
|
|
|
/* Initial state may encounter the byte which is not a singlebyte character
|
|
nor 1st byte of a multibyte character. But it is incorrect for initial
|
|
state to accept such a byte.
|
|
For example, in sjis encoding the regular expression like "\\" accepts
|
|
the codepoint 0x5c, but should not accept the 2nd byte of the codepoint
|
|
0x815c. Then Initial state must skip the bytes which are not a singlebyte
|
|
character nor 1st byte of a multibyte character. */
|
|
#define SKIP_REMAINS_MB_IF_INITIAL_STATE(s, p) \
|
|
if (s == 0) \
|
|
{ \
|
|
while (inputwcs[p - buf_begin] == 0 \
|
|
&& mblen_buf[p - buf_begin] > 0 \
|
|
&& p < buf_end) \
|
|
++p; \
|
|
if (p >= end) \
|
|
{ \
|
|
free(mblen_buf); \
|
|
free(inputwcs); \
|
|
return (size_t) -1; \
|
|
} \
|
|
}
|
|
|
|
static void
|
|
realloc_trans_if_necessary(struct dfa *d, int new_state)
|
|
{
|
|
/* Make sure that the trans and fail arrays are allocated large enough
|
|
to hold a pointer for the new state. */
|
|
if (new_state >= d->tralloc)
|
|
{
|
|
int oldalloc = d->tralloc;
|
|
|
|
while (new_state >= 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;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Return values of transit_state_singlebyte(), and
|
|
transit_state_consume_1char. */
|
|
typedef enum
|
|
{
|
|
TRANSIT_STATE_IN_PROGRESS, /* State transition has not finished. */
|
|
TRANSIT_STATE_DONE, /* State transition has finished. */
|
|
TRANSIT_STATE_END_BUFFER /* Reach the end of the buffer. */
|
|
} status_transit_state;
|
|
|
|
/* Consume a single byte and transit state from 's' to '*next_state'.
|
|
This function is almost same as the state transition routin in dfaexec().
|
|
But state transition is done just once, otherwise matching succeed or
|
|
reach the end of the buffer. */
|
|
static status_transit_state
|
|
transit_state_singlebyte (struct dfa *d, int s, unsigned char const *p,
|
|
int *next_state)
|
|
{
|
|
int *t;
|
|
int works = s;
|
|
|
|
status_transit_state rval = TRANSIT_STATE_IN_PROGRESS;
|
|
|
|
while (rval == TRANSIT_STATE_IN_PROGRESS)
|
|
{
|
|
if ((t = d->trans[works]) != NULL)
|
|
{
|
|
works = t[*p];
|
|
rval = TRANSIT_STATE_DONE;
|
|
if (works < 0)
|
|
works = 0;
|
|
}
|
|
else if (works < 0)
|
|
{
|
|
if (p == buf_end)
|
|
/* At the moment, it must not happen. */
|
|
return TRANSIT_STATE_END_BUFFER;
|
|
works = 0;
|
|
}
|
|
else if (d->fails[works])
|
|
{
|
|
works = d->fails[works][*p];
|
|
rval = TRANSIT_STATE_DONE;
|
|
}
|
|
else
|
|
{
|
|
build_state(works, d);
|
|
}
|
|
}
|
|
*next_state = works;
|
|
return rval;
|
|
}
|
|
|
|
/* Check whether period can match or not in the current context. If it can,
|
|
return the amount of the bytes with which period can match, otherwise
|
|
return 0.
|
|
`pos' is the position of the period. `index' is the index from the
|
|
buf_begin, and it is the current position in the buffer. */
|
|
static int
|
|
match_anychar (struct dfa *d, int s, position pos, int index)
|
|
{
|
|
int newline = 0;
|
|
int letter = 0;
|
|
wchar_t wc;
|
|
int mbclen;
|
|
|
|
wc = inputwcs[index];
|
|
mbclen = (mblen_buf[index] == 0)? 1 : mblen_buf[index];
|
|
|
|
/* Check context. */
|
|
if (wc == (wchar_t)eolbyte)
|
|
{
|
|
if (!(syntax_bits & RE_DOT_NEWLINE))
|
|
return 0;
|
|
newline = 1;
|
|
}
|
|
else if (wc == (wchar_t)'\0')
|
|
{
|
|
if (syntax_bits & RE_DOT_NOT_NULL)
|
|
return 0;
|
|
newline = 1;
|
|
}
|
|
|
|
if (iswalnum(wc) || wc == L'_')
|
|
letter = 1;
|
|
|
|
if (!SUCCEEDS_IN_CONTEXT(pos.constraint, d->states[s].newline,
|
|
newline, d->states[s].letter, letter))
|
|
return 0;
|
|
|
|
return mbclen;
|
|
}
|
|
|
|
/* Check whether bracket expression can match or not in the current context.
|
|
If it can, return the amount of the bytes with which expression can match,
|
|
otherwise return 0.
|
|
`pos' is the position of the bracket expression. `index' is the index
|
|
from the buf_begin, and it is the current position in the buffer. */
|
|
int
|
|
match_mb_charset (struct dfa *d, int s, position pos, int index)
|
|
{
|
|
int i;
|
|
int match; /* Flag which represent that matching succeed. */
|
|
int match_len; /* Length of the character (or collating element)
|
|
with which this operator match. */
|
|
int op_len; /* Length of the operator. */
|
|
char buffer[128];
|
|
wchar_t wcbuf[6];
|
|
|
|
/* Pointer to the structure to which we are currently reffering. */
|
|
struct mb_char_classes *work_mbc;
|
|
|
|
int newline = 0;
|
|
int letter = 0;
|
|
wchar_t wc; /* Current reffering character. */
|
|
|
|
wc = inputwcs[index];
|
|
|
|
/* Check context. */
|
|
if (wc == (wchar_t)eolbyte)
|
|
{
|
|
if (!(syntax_bits & RE_DOT_NEWLINE))
|
|
return 0;
|
|
newline = 1;
|
|
}
|
|
else if (wc == (wchar_t)'\0')
|
|
{
|
|
if (syntax_bits & RE_DOT_NOT_NULL)
|
|
return 0;
|
|
newline = 1;
|
|
}
|
|
if (iswalnum(wc) || wc == L'_')
|
|
letter = 1;
|
|
if (!SUCCEEDS_IN_CONTEXT(pos.constraint, d->states[s].newline,
|
|
newline, d->states[s].letter, letter))
|
|
return 0;
|
|
|
|
/* Assign the current reffering operator to work_mbc. */
|
|
work_mbc = &(d->mbcsets[(d->multibyte_prop[pos.index]) >> 2]);
|
|
match = !work_mbc->invert;
|
|
match_len = (mblen_buf[index] == 0)? 1 : mblen_buf[index];
|
|
|
|
/* match with a character class? */
|
|
for (i = 0; i<work_mbc->nch_classes; i++)
|
|
{
|
|
if (iswctype((wint_t)wc, work_mbc->ch_classes[i]))
|
|
goto charset_matched;
|
|
}
|
|
|
|
strncpy(buffer, buf_begin + index, match_len);
|
|
buffer[match_len] = '\0';
|
|
|
|
/* match with an equivalent class? */
|
|
for (i = 0; i<work_mbc->nequivs; i++)
|
|
{
|
|
op_len = strlen(work_mbc->equivs[i]);
|
|
strncpy(buffer, buf_begin + index, op_len);
|
|
buffer[op_len] = '\0';
|
|
if (strcoll(work_mbc->equivs[i], buffer) == 0)
|
|
{
|
|
match_len = op_len;
|
|
goto charset_matched;
|
|
}
|
|
}
|
|
|
|
/* match with a collating element? */
|
|
for (i = 0; i<work_mbc->ncoll_elems; i++)
|
|
{
|
|
op_len = strlen(work_mbc->coll_elems[i]);
|
|
strncpy(buffer, buf_begin + index, op_len);
|
|
buffer[op_len] = '\0';
|
|
|
|
if (strcoll(work_mbc->coll_elems[i], buffer) == 0)
|
|
{
|
|
match_len = op_len;
|
|
goto charset_matched;
|
|
}
|
|
}
|
|
|
|
wcbuf[0] = wc;
|
|
wcbuf[1] = wcbuf[3] = wcbuf[5] = '\0';
|
|
|
|
/* match with a range? */
|
|
for (i = 0; i<work_mbc->nranges; i++)
|
|
{
|
|
wcbuf[2] = work_mbc->range_sts[i];
|
|
wcbuf[4] = work_mbc->range_ends[i];
|
|
|
|
if (wcscoll(wcbuf, wcbuf+2) >= 0 &&
|
|
wcscoll(wcbuf+4, wcbuf) >= 0)
|
|
goto charset_matched;
|
|
}
|
|
|
|
/* match with a character? */
|
|
for (i = 0; i<work_mbc->nchars; i++)
|
|
{
|
|
if (wc == work_mbc->chars[i])
|
|
goto charset_matched;
|
|
}
|
|
|
|
match = !match;
|
|
|
|
charset_matched:
|
|
return match ? match_len : 0;
|
|
}
|
|
|
|
/* Check each of `d->states[s].mbps.elem' can match or not. Then return the
|
|
array which corresponds to `d->states[s].mbps.elem' and each element of
|
|
the array contains the amount of the bytes with which the element can
|
|
match.
|
|
`index' is the index from the buf_begin, and it is the current position
|
|
in the buffer.
|
|
Caller MUST free the array which this function return. */
|
|
static int*
|
|
check_matching_with_multibyte_ops (struct dfa *d, int s, int index)
|
|
{
|
|
int i;
|
|
int* rarray;
|
|
|
|
MALLOC(rarray, int, d->states[s].mbps.nelem);
|
|
for (i = 0; i < d->states[s].mbps.nelem; ++i)
|
|
{
|
|
position pos = d->states[s].mbps.elems[i];
|
|
switch(d->tokens[pos.index])
|
|
{
|
|
case ANYCHAR:
|
|
rarray[i] = match_anychar(d, s, pos, index);
|
|
break;
|
|
case MBCSET:
|
|
rarray[i] = match_mb_charset(d, s, pos, index);
|
|
break;
|
|
default:
|
|
break; /* can not happen. */
|
|
}
|
|
}
|
|
return rarray;
|
|
}
|
|
|
|
/* Consume a single character and enumerate all of the positions which can
|
|
be next position from the state `s'.
|
|
`match_lens' is the input. It can be NULL, but it can also be the output
|
|
of check_matching_with_multibyte_ops() for optimization.
|
|
`mbclen' and `pps' are the output. `mbclen' is the length of the
|
|
character consumed, and `pps' is the set this function enumerate. */
|
|
static status_transit_state
|
|
transit_state_consume_1char (struct dfa *d, int s, unsigned char const **pp,
|
|
int *match_lens, int *mbclen, position_set *pps)
|
|
{
|
|
int i, j;
|
|
int s1, s2;
|
|
int* work_mbls;
|
|
status_transit_state rs = TRANSIT_STATE_DONE;
|
|
|
|
/* Calculate the length of the (single/multi byte) character
|
|
to which p points. */
|
|
*mbclen = (mblen_buf[*pp - buf_begin] == 0)? 1
|
|
: mblen_buf[*pp - buf_begin];
|
|
|
|
/* Calculate the state which can be reached from the state `s' by
|
|
consuming `*mbclen' single bytes from the buffer. */
|
|
s1 = s;
|
|
for (i = 0; i < *mbclen; i++)
|
|
{
|
|
s2 = s1;
|
|
rs = transit_state_singlebyte(d, s2, (*pp)++, &s1);
|
|
}
|
|
/* Copy the positions contained by `s1' to the set `pps'. */
|
|
copy(&(d->states[s1].elems), pps);
|
|
|
|
/* Check (inputed)match_lens, and initialize if it is NULL. */
|
|
if (match_lens == NULL && d->states[s].mbps.nelem != 0)
|
|
work_mbls = check_matching_with_multibyte_ops(d, s, *pp - buf_begin);
|
|
else
|
|
work_mbls = match_lens;
|
|
|
|
/* Add all of the positions which can be reached from `s' by consuming
|
|
a single character. */
|
|
for (i = 0; i < d->states[s].mbps.nelem ; i++)
|
|
{
|
|
if (work_mbls[i] == *mbclen)
|
|
for (j = 0; j < d->follows[d->states[s].mbps.elems[i].index].nelem;
|
|
j++)
|
|
insert(d->follows[d->states[s].mbps.elems[i].index].elems[j],
|
|
pps);
|
|
}
|
|
|
|
if (match_lens == NULL && work_mbls != NULL)
|
|
free(work_mbls);
|
|
return rs;
|
|
}
|
|
|
|
/* Transit state from s, then return new state and update the pointer of the
|
|
buffer. This function is for some operator which can match with a multi-
|
|
byte character or a collating element(which may be multi characters). */
|
|
static int
|
|
transit_state (struct dfa *d, int s, unsigned char const **pp)
|
|
{
|
|
int s1;
|
|
int mbclen; /* The length of current input multibyte character. */
|
|
int maxlen = 0;
|
|
int i, j;
|
|
int *match_lens = NULL;
|
|
int nelem = d->states[s].mbps.nelem; /* Just a alias. */
|
|
position_set follows;
|
|
unsigned char const *p1 = *pp;
|
|
status_transit_state rs;
|
|
wchar_t wc;
|
|
|
|
if (nelem > 0)
|
|
/* This state has (a) multibyte operator(s).
|
|
We check whether each of them can match or not. */
|
|
{
|
|
/* Note: caller must free the return value of this function. */
|
|
match_lens = check_matching_with_multibyte_ops(d, s, *pp - buf_begin);
|
|
|
|
for (i = 0; i < nelem; i++)
|
|
/* Search the operator which match the longest string,
|
|
in this state. */
|
|
{
|
|
if (match_lens[i] > maxlen)
|
|
maxlen = match_lens[i];
|
|
}
|
|
}
|
|
|
|
if (nelem == 0 || maxlen == 0)
|
|
/* This state has no multibyte operator which can match.
|
|
We need to check only one singlebyte character. */
|
|
{
|
|
status_transit_state rs;
|
|
rs = transit_state_singlebyte(d, s, *pp, &s1);
|
|
|
|
/* We must update the pointer if state transition succeeded. */
|
|
if (rs == TRANSIT_STATE_DONE)
|
|
++*pp;
|
|
|
|
if (match_lens != NULL)
|
|
free(match_lens);
|
|
return s1;
|
|
}
|
|
|
|
/* This state has some operators which can match a multibyte character. */
|
|
follows.nelem = 0;
|
|
MALLOC(follows.elems, position, d->nleaves);
|
|
|
|
/* `maxlen' may be longer than the length of a character, because it may
|
|
not be a character but a (multi character) collating element.
|
|
We enumerate all of the positions which `s' can reach by consuming
|
|
`maxlen' bytes. */
|
|
rs = transit_state_consume_1char(d, s, pp, match_lens, &mbclen, &follows);
|
|
|
|
wc = inputwcs[*pp - mbclen - buf_begin];
|
|
s1 = state_index(d, &follows, wc == L'\n', iswalnum(wc));
|
|
realloc_trans_if_necessary(d, s1);
|
|
|
|
while (*pp - p1 < maxlen)
|
|
{
|
|
follows.nelem = 0;
|
|
rs = transit_state_consume_1char(d, s1, pp, NULL, &mbclen, &follows);
|
|
|
|
for (i = 0; i < nelem ; i++)
|
|
{
|
|
if (match_lens[i] == *pp - p1)
|
|
for (j = 0;
|
|
j < d->follows[d->states[s1].mbps.elems[i].index].nelem; j++)
|
|
insert(d->follows[d->states[s1].mbps.elems[i].index].elems[j],
|
|
&follows);
|
|
}
|
|
|
|
wc = inputwcs[*pp - mbclen - buf_begin];
|
|
s1 = state_index(d, &follows, wc == L'\n', iswalnum(wc));
|
|
realloc_trans_if_necessary(d, s1);
|
|
}
|
|
free(match_lens);
|
|
free(follows.elems);
|
|
return s1;
|
|
}
|
|
|
|
#endif
|
|
|
|
/* 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,
|
|
struct mb_cache *mb_cache)
|
|
{
|
|
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;
|
|
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
buf_begin = begin;
|
|
buf_end = end;
|
|
if (mb_cache && mb_cache->mblen_buf && mb_cache->wcs_buf &&
|
|
begin > mb_cache->orig_buf &&
|
|
(begin + size) <= (mb_cache->orig_buf + mb_cache->len))
|
|
{
|
|
/* The cache can help us. */
|
|
MALLOC(mblen_buf, unsigned char, size + 2);
|
|
MALLOC(inputwcs, wchar_t, size + 2);
|
|
memcpy (mblen_buf,
|
|
mb_cache->mblen_buf + (begin - mb_cache->orig_buf),
|
|
(size + 2) * sizeof (unsigned char));
|
|
memcpy (inputwcs,
|
|
mb_cache->wcs_buf + (begin - mb_cache->orig_buf),
|
|
(size + 2) * sizeof (wchar_t));
|
|
mblen_buf[size + 1] = 0;
|
|
inputwcs[size + 1] = 0;
|
|
}
|
|
else
|
|
{
|
|
int remain_bytes, i;
|
|
|
|
/* initialize mblen_buf, and inputwcs. */
|
|
MALLOC(mblen_buf, unsigned char, end - (unsigned char const *)begin + 2);
|
|
MALLOC(inputwcs, wchar_t, end - (unsigned char const *)begin + 2);
|
|
memset(&mbs, 0, sizeof(mbstate_t));
|
|
remain_bytes = 0;
|
|
for (i = 0; i < end - (unsigned char const *)begin + 1; i++)
|
|
{
|
|
if (remain_bytes == 0)
|
|
{
|
|
remain_bytes
|
|
= mbrtowc(inputwcs + i, begin + i,
|
|
end - (unsigned char const *)begin - i + 1, &mbs);
|
|
if (remain_bytes <= 1)
|
|
{
|
|
remain_bytes = 0;
|
|
inputwcs[i] = (wchar_t)begin[i];
|
|
mblen_buf[i] = 0;
|
|
}
|
|
else
|
|
{
|
|
mblen_buf[i] = remain_bytes;
|
|
remain_bytes--;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
mblen_buf[i] = remain_bytes;
|
|
inputwcs[i] = 0;
|
|
remain_bytes--;
|
|
}
|
|
}
|
|
mblen_buf[i] = 0;
|
|
inputwcs[i] = 0; /* sentinel */
|
|
|
|
if (mb_cache)
|
|
{
|
|
/* Populate the cache. */
|
|
mb_cache->len = size;
|
|
mb_cache->orig_buf = begin;
|
|
if (mb_cache->mblen_buf)
|
|
free (mb_cache->mblen_buf);
|
|
if (mb_cache->wcs_buf)
|
|
free (mb_cache->wcs_buf);
|
|
MALLOC(mb_cache->mblen_buf, unsigned char, size + 2);
|
|
MALLOC(mb_cache->wcs_buf, wchar_t, size + 2);
|
|
memcpy (mb_cache->mblen_buf, mblen_buf,
|
|
(size + 2) * sizeof (unsigned char));
|
|
memcpy (mb_cache->wcs_buf, inputwcs,
|
|
(size + 2) * sizeof (wchar_t));
|
|
}
|
|
}
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
|
|
for (;;)
|
|
{
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
while ((t = trans[s]))
|
|
{
|
|
if (d->states[s].mbps.nelem != 0)
|
|
{
|
|
/* Can match with a multibyte character( and multi character
|
|
collating element). */
|
|
unsigned char const *nextp;
|
|
|
|
SKIP_REMAINS_MB_IF_INITIAL_STATE(s, p);
|
|
|
|
nextp = p;
|
|
s = transit_state(d, s, &nextp);
|
|
p = nextp;
|
|
|
|
/* Trans table might be updated. */
|
|
trans = d->trans;
|
|
}
|
|
else
|
|
{
|
|
SKIP_REMAINS_MB_IF_INITIAL_STATE(s, p);
|
|
s = t[*p++];
|
|
}
|
|
}
|
|
else
|
|
#endif /* MBS_SUPPORT */
|
|
while ((t = trans[s]))
|
|
s = t[*p++];
|
|
|
|
if (s < 0)
|
|
{
|
|
if (p == end)
|
|
{
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
free(mblen_buf);
|
|
free(inputwcs);
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
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);
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
free(mblen_buf);
|
|
free(inputwcs);
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
return (char const *) p - begin;
|
|
}
|
|
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
SKIP_REMAINS_MB_IF_INITIAL_STATE(s, p);
|
|
if (d->states[s].mbps.nelem != 0)
|
|
{
|
|
/* Can match with a multibyte character( and multi
|
|
character collating element). */
|
|
unsigned char const *nextp;
|
|
nextp = p;
|
|
s = transit_state(d, s, &nextp);
|
|
p = nextp;
|
|
|
|
/* Trans table might be updated. */
|
|
trans = d->trans;
|
|
}
|
|
else
|
|
s = t[*p++];
|
|
}
|
|
else
|
|
#endif /* MBS_SUPPORT */
|
|
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;
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
d->nmultibyte_prop = 1;
|
|
MALLOC(d->multibyte_prop, int, d->nmultibyte_prop);
|
|
d->nmbcsets = 0;
|
|
d->mbcsets_alloc = 1;
|
|
MALLOC(d->mbcsets, struct mb_char_classes, d->mbcsets_alloc);
|
|
}
|
|
#endif
|
|
|
|
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 = malloc(len);
|
|
if (!lcopy)
|
|
dfaerror(_("out of memory"));
|
|
|
|
/* 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);
|
|
}
|
|
}
|
|
|
|
/* Free the storage held by the components of a dfa. */
|
|
void
|
|
dfafree (struct dfa *d)
|
|
{
|
|
int i;
|
|
struct dfamust *dm, *ndm;
|
|
|
|
free((ptr_t) d->charclasses);
|
|
free((ptr_t) d->tokens);
|
|
|
|
#ifdef MBS_SUPPORT
|
|
if (MB_CUR_MAX > 1)
|
|
{
|
|
free((ptr_t) d->multibyte_prop);
|
|
for (i = 0; i < d->nmbcsets; ++i)
|
|
{
|
|
int j;
|
|
struct mb_char_classes *p = &(d->mbcsets[i]);
|
|
if (p->chars != NULL)
|
|
free(p->chars);
|
|
if (p->ch_classes != NULL)
|
|
free(p->ch_classes);
|
|
if (p->range_sts != NULL)
|
|
free(p->range_sts);
|
|
if (p->range_ends != NULL)
|
|
free(p->range_ends);
|
|
|
|
for (j = 0; j < p->nequivs; ++j)
|
|
free(p->equivs[j]);
|
|
if (p->equivs != NULL)
|
|
free(p->equivs);
|
|
|
|
for (j = 0; j < p->ncoll_elems; ++j)
|
|
free(p->coll_elems[j]);
|
|
if (p->coll_elems != NULL)
|
|
free(p->coll_elems);
|
|
}
|
|
free((ptr_t) d->mbcsets);
|
|
}
|
|
#endif /* MBS_SUPPORT */
|
|
|
|
for (i = 0; i < d->sindex; ++i)
|
|
free((ptr_t) d->states[i].elems.elems);
|
|
free((ptr_t) d->states);
|
|
for (i = 0; i < d->tindex; ++i)
|
|
if (d->follows[i].elems)
|
|
free((ptr_t) d->follows[i].elems);
|
|
free((ptr_t) d->follows);
|
|
for (i = 0; i < d->tralloc; ++i)
|
|
if (d->trans[i])
|
|
free((ptr_t) d->trans[i]);
|
|
else if (d->fails[i])
|
|
free((ptr_t) d->fails[i]);
|
|
if (d->realtrans) free((ptr_t) d->realtrans);
|
|
if (d->fails) free((ptr_t) d->fails);
|
|
if (d->success) free((ptr_t) d->success);
|
|
for (dm = d->musts; dm; dm = ndm)
|
|
{
|
|
ndm = dm->next;
|
|
free(dm->must);
|
|
free((ptr_t) dm);
|
|
}
|
|
}
|
|
|
|
/* Having found the postfix representation of the regular expression,
|
|
try to find a long sequence of characters that must appear in any line
|
|
containing the r.e.
|
|
Finding a "longest" sequence is beyond the scope here;
|
|
we take an easy way out and hope for the best.
|
|
(Take "(ab|a)b"--please.)
|
|
|
|
We do a bottom-up calculation of sequences of characters that must appear
|
|
in matches of r.e.'s represented by trees rooted at the nodes of the postfix
|
|
representation:
|
|
sequences that must appear at the left of the match ("left")
|
|
sequences that must appear at the right of the match ("right")
|
|
lists of sequences that must appear somewhere in the match ("in")
|
|
sequences that must constitute the match ("is")
|
|
|
|
When we get to the root of the tree, we use one of the longest of its
|
|
calculated "in" sequences as our answer. The sequence we find is returned in
|
|
d->must (where "d" is the single argument passed to "dfamust");
|
|
the length of the sequence is returned in d->mustn.
|
|
|
|
The sequences calculated for the various types of node (in pseudo ANSI c)
|
|
are shown below. "p" is the operand of unary operators (and the left-hand
|
|
operand of binary operators); "q" is the right-hand operand of binary
|
|
operators.
|
|
|
|
"ZERO" means "a zero-length sequence" below.
|
|
|
|
Type left right is in
|
|
---- ---- ----- -- --
|
|
char c # c # c # c # c
|
|
|
|
ANYCHAR ZERO ZERO ZERO ZERO
|
|
|
|
MBCSET ZERO ZERO ZERO ZERO
|
|
|
|
CSET ZERO ZERO ZERO ZERO
|
|
|
|
STAR ZERO ZERO ZERO ZERO
|
|
|
|
QMARK ZERO ZERO ZERO ZERO
|
|
|
|
PLUS p->left p->right ZERO p->in
|
|
|
|
CAT (p->is==ZERO)? (q->is==ZERO)? (p->is!=ZERO && p->in plus
|
|
p->left : q->right : q->is!=ZERO) ? q->in plus
|
|
p->is##q->left p->right##q->is p->is##q->is : p->right##q->left
|
|
ZERO
|
|
|
|
OR longest common longest common (do p->is and substrings common to
|
|
leading trailing q->is have same p->in and q->in
|
|
(sub)sequence (sub)sequence length and
|
|
of p->left of p->right content) ?
|
|
and q->left and q->right p->is : NULL
|
|
|
|
If there's anything else we recognize in the tree, all four sequences get set
|
|
to zero-length sequences. If there's something we don't recognize in the tree,
|
|
we just return a zero-length sequence.
|
|
|
|
Break ties in favor of infrequent letters (choosing 'zzz' in preference to
|
|
'aaa')?
|
|
|
|
And. . .is it here or someplace that we might ponder "optimizations" such as
|
|
egrep 'psi|epsilon' -> egrep 'psi'
|
|
egrep 'pepsi|epsilon' -> egrep 'epsi'
|
|
(Yes, we now find "epsi" as a "string
|
|
that must occur", but we might also
|
|
simplify the *entire* r.e. being sought)
|
|
grep '[c]' -> grep 'c'
|
|
grep '(ab|a)b' -> grep 'ab'
|
|
grep 'ab*' -> grep 'a'
|
|
grep 'a*b' -> grep 'b'
|
|
|
|
There are several issues:
|
|
|
|
Is optimization easy (enough)?
|
|
|
|
Does optimization actually accomplish anything,
|
|
or is the automaton you get from "psi|epsilon" (for example)
|
|
the same as the one you get from "psi" (for example)?
|
|
|
|
Are optimizable r.e.'s likely to be used in real-life situations
|
|
(something like 'ab*' is probably unlikely; something like is
|
|
'psi|epsilon' is likelier)? */
|
|
|
|
static char *
|
|
icatalloc (char *old, char *new)
|
|
{
|
|
char *result;
|
|
size_t oldsize, newsize;
|
|
|
|
newsize = (new == NULL) ? 0 : strlen(new);
|
|
if (old == NULL)
|
|
oldsize = 0;
|
|
else if (newsize == 0)
|
|
return old;
|
|
else oldsize = strlen(old);
|
|
if (old == NULL)
|
|
result = (char *) malloc(newsize + 1);
|
|
else
|
|
result = (char *) realloc((void *) old, oldsize + newsize + 1);
|
|
if (result != NULL && new != NULL)
|
|
(void) strcpy(result + oldsize, new);
|
|
return result;
|
|
}
|
|
|
|
static char *
|
|
icpyalloc (char *string)
|
|
{
|
|
return icatalloc((char *) NULL, string);
|
|
}
|
|
|
|
static char *
|
|
istrstr (char *lookin, char *lookfor)
|
|
{
|
|
char *cp;
|
|
size_t len;
|
|
|
|
len = strlen(lookfor);
|
|
for (cp = lookin; *cp != '\0'; ++cp)
|
|
if (strncmp(cp, lookfor, len) == 0)
|
|
return cp;
|
|
return NULL;
|
|
}
|
|
|
|
static void
|
|
ifree (char *cp)
|
|
{
|
|
if (cp != NULL)
|
|
free(cp);
|
|
}
|
|
|
|
static void
|
|
freelist (char **cpp)
|
|
{
|
|
int i;
|
|
|
|
if (cpp == NULL)
|
|
return;
|
|
for (i = 0; cpp[i] != NULL; ++i)
|
|
{
|
|
free(cpp[i]);
|
|
cpp[i] = NULL;
|
|
}
|
|
}
|
|
|
|
static char **
|
|
enlist (char **cpp, char *new, size_t len)
|
|
{
|
|
int i, j;
|
|
|
|
if (cpp == NULL)
|
|
return NULL;
|
|
if ((new = icpyalloc(new)) == NULL)
|
|
{
|
|
freelist(cpp);
|
|
return NULL;
|
|
}
|
|
new[len] = '\0';
|
|
/* Is there already something in the list that's new (or longer)? */
|
|
for (i = 0; cpp[i] != NULL; ++i)
|
|
if (istrstr(cpp[i], new) != NULL)
|
|
{
|
|
free(new);
|
|
return cpp;
|
|
}
|
|
/* Eliminate any obsoleted strings. */
|
|
j = 0;
|
|
while (cpp[j] != NULL)
|
|
if (istrstr(new, cpp[j]) == NULL)
|
|
++j;
|
|
else
|
|
{
|
|
free(cpp[j]);
|
|
if (--i == j)
|
|
break;
|
|
cpp[j] = cpp[i];
|
|
cpp[i] = NULL;
|
|
}
|
|
/* Add the new string. */
|
|
cpp = (char **) realloc((char *) cpp, (i + 2) * sizeof *cpp);
|
|
if (cpp == NULL)
|
|
return NULL;
|
|
cpp[i] = new;
|
|
cpp[i + 1] = NULL;
|
|
return cpp;
|
|
}
|
|
|
|
/* Given pointers to two strings, return a pointer to an allocated
|
|
list of their distinct common substrings. Return NULL if something
|
|
seems wild. */
|
|
static char **
|
|
comsubs (char *left, char *right)
|
|
{
|
|
char **cpp;
|
|
char *lcp;
|
|
char *rcp;
|
|
size_t i, len;
|
|
|
|
if (left == NULL || right == NULL)
|
|
return NULL;
|
|
cpp = (char **) malloc(sizeof *cpp);
|
|
if (cpp == NULL)
|
|
return NULL;
|
|
cpp[0] = NULL;
|
|
for (lcp = left; *lcp != '\0'; ++lcp)
|
|
{
|
|
len = 0;
|
|
rcp = strchr (right, *lcp);
|
|
while (rcp != NULL)
|
|
{
|
|
for (i = 1; lcp[i] != '\0' && lcp[i] == rcp[i]; ++i)
|
|
continue;
|
|
if (i > len)
|
|
len = i;
|
|
rcp = strchr (rcp + 1, *lcp);
|
|
}
|
|
if (len == 0)
|
|
continue;
|
|
if ((cpp = enlist(cpp, lcp, len)) == NULL)
|
|
break;
|
|
}
|
|
return cpp;
|
|
}
|
|
|
|
static char **
|
|
addlists (char **old, char **new)
|
|
{
|
|
int i;
|
|
|
|
if (old == NULL || new == NULL)
|
|
return NULL;
|
|
for (i = 0; new[i] != NULL; ++i)
|
|
{
|
|
old = enlist(old, new[i], strlen(new[i]));
|
|
if (old == NULL)
|
|
break;
|
|
}
|
|
return old;
|
|
}
|
|
|
|
/* Given two lists of substrings, return a new list giving substrings
|
|
common to both. */
|
|
static char **
|
|
inboth (char **left, char **right)
|
|
{
|
|
char **both;
|
|
char **temp;
|
|
int lnum, rnum;
|
|
|
|
if (left == NULL || right == NULL)
|
|
return NULL;
|
|
both = (char **) malloc(sizeof *both);
|
|
if (both == NULL)
|
|
return NULL;
|
|
both[0] = NULL;
|
|
for (lnum = 0; left[lnum] != NULL; ++lnum)
|
|
{
|
|
for (rnum = 0; right[rnum] != NULL; ++rnum)
|
|
{
|
|
temp = comsubs(left[lnum], right[rnum]);
|
|
if (temp == NULL)
|
|
{
|
|
freelist(both);
|
|
return NULL;
|
|
}
|
|
both = addlists(both, temp);
|
|
freelist(temp);
|
|
free(temp);
|
|
if (both == NULL)
|
|
return NULL;
|
|
}
|
|
}
|
|
return both;
|
|
}
|
|
|
|
typedef struct
|
|
{
|
|
char **in;
|
|
char *left;
|
|
char *right;
|
|
char *is;
|
|
} must;
|
|
|
|
static void
|
|
resetmust (must *mp)
|
|
{
|
|
mp->left[0] = mp->right[0] = mp->is[0] = '\0';
|
|
freelist(mp->in);
|
|
}
|
|
|
|
static void
|
|
dfamust (struct dfa *dfa)
|
|
{
|
|
must *musts;
|
|
must *mp;
|
|
char *result;
|
|
int ri;
|
|
int i;
|
|
int exact;
|
|
token t;
|
|
static must must0;
|
|
struct dfamust *dm;
|
|
static char empty_string[] = "";
|
|
|
|
result = empty_string;
|
|
exact = 0;
|
|
musts = (must *) malloc((dfa->tindex + 1) * sizeof *musts);
|
|
if (musts == NULL)
|
|
return;
|
|
mp = musts;
|
|
for (i = 0; i <= dfa->tindex; ++i)
|
|
mp[i] = must0;
|
|
for (i = 0; i <= dfa->tindex; ++i)
|
|
{
|
|
mp[i].in = (char **) malloc(sizeof *mp[i].in);
|
|
mp[i].left = malloc(2);
|
|
mp[i].right = malloc(2);
|
|
mp[i].is = malloc(2);
|
|
if (mp[i].in == NULL || mp[i].left == NULL ||
|
|
mp[i].right == NULL || mp[i].is == NULL)
|
|
goto done;
|
|
mp[i].left[0] = mp[i].right[0] = mp[i].is[0] = '\0';
|
|
mp[i].in[0] = NULL;
|
|
}
|
|
#ifdef DEBUG
|
|
fprintf(stderr, "dfamust:\n");
|
|
for (i = 0; i < dfa->tindex; ++i)
|
|
{
|
|
fprintf(stderr, " %d:", i);
|
|
prtok(dfa->tokens[i]);
|
|
}
|
|
putc('\n', stderr);
|
|
#endif
|
|
for (ri = 0; ri < dfa->tindex; ++ri)
|
|
{
|
|
switch (t = dfa->tokens[ri])
|
|
{
|
|
case LPAREN:
|
|
case RPAREN:
|
|
goto done; /* "cannot happen" */
|
|
case EMPTY:
|
|
case BEGLINE:
|
|
case ENDLINE:
|
|
case BEGWORD:
|
|
case ENDWORD:
|
|
case LIMWORD:
|
|
case NOTLIMWORD:
|
|
case BACKREF:
|
|
resetmust(mp);
|
|
break;
|
|
case STAR:
|
|
case QMARK:
|
|
if (mp <= musts)
|
|
goto done; /* "cannot happen" */
|
|
--mp;
|
|
resetmust(mp);
|
|
break;
|
|
case OR:
|
|
case ORTOP:
|
|
if (mp < &musts[2])
|
|
goto done; /* "cannot happen" */
|
|
{
|
|
char **new;
|
|
must *lmp;
|
|
must *rmp;
|
|
int j, ln, rn, n;
|
|
|
|
rmp = --mp;
|
|
lmp = --mp;
|
|
/* Guaranteed to be. Unlikely, but. . . */
|
|
if (strcmp(lmp->is, rmp->is) != 0)
|
|
lmp->is[0] = '\0';
|
|
/* Left side--easy */
|
|
i = 0;
|
|
while (lmp->left[i] != '\0' && lmp->left[i] == rmp->left[i])
|
|
++i;
|
|
lmp->left[i] = '\0';
|
|
/* Right side */
|
|
ln = strlen(lmp->right);
|
|
rn = strlen(rmp->right);
|
|
n = ln;
|
|
if (n > rn)
|
|
n = rn;
|
|
for (i = 0; i < n; ++i)
|
|
if (lmp->right[ln - i - 1] != rmp->right[rn - i - 1])
|
|
break;
|
|
for (j = 0; j < i; ++j)
|
|
lmp->right[j] = lmp->right[(ln - i) + j];
|
|
lmp->right[j] = '\0';
|
|
new = inboth(lmp->in, rmp->in);
|
|
if (new == NULL)
|
|
goto done;
|
|
freelist(lmp->in);
|
|
free((char *) lmp->in);
|
|
lmp->in = new;
|
|
}
|
|
break;
|
|
case PLUS:
|
|
if (mp <= musts)
|
|
goto done; /* "cannot happen" */
|
|
--mp;
|
|
mp->is[0] = '\0';
|
|
break;
|
|
case END:
|
|
if (mp != &musts[1])
|
|
goto done; /* "cannot happen" */
|
|
for (i = 0; musts[0].in[i] != NULL; ++i)
|
|
if (strlen(musts[0].in[i]) > strlen(result))
|
|
result = musts[0].in[i];
|
|
if (strcmp(result, musts[0].is) == 0)
|
|
exact = 1;
|
|
goto done;
|
|
case CAT:
|
|
if (mp < &musts[2])
|
|
goto done; /* "cannot happen" */
|
|
{
|
|
must *lmp;
|
|
must *rmp;
|
|
|
|
rmp = --mp;
|
|
lmp = --mp;
|
|
/* In. Everything in left, plus everything in
|
|
right, plus catenation of
|
|
left's right and right's left. */
|
|
lmp->in = addlists(lmp->in, rmp->in);
|
|
if (lmp->in == NULL)
|
|
goto done;
|
|
if (lmp->right[0] != '\0' &&
|
|
rmp->left[0] != '\0')
|
|
{
|
|
char *tp;
|
|
|
|
tp = icpyalloc(lmp->right);
|
|
if (tp == NULL)
|
|
goto done;
|
|
tp = icatalloc(tp, rmp->left);
|
|
if (tp == NULL)
|
|
goto done;
|
|
lmp->in = enlist(lmp->in, tp,
|
|
strlen(tp));
|
|
free(tp);
|
|
if (lmp->in == NULL)
|
|
goto done;
|
|
}
|
|
/* Left-hand */
|
|
if (lmp->is[0] != '\0')
|
|
{
|
|
lmp->left = icatalloc(lmp->left,
|
|
rmp->left);
|
|
if (lmp->left == NULL)
|
|
goto done;
|
|
}
|
|
/* Right-hand */
|
|
if (rmp->is[0] == '\0')
|
|
lmp->right[0] = '\0';
|
|
lmp->right = icatalloc(lmp->right, rmp->right);
|
|
if (lmp->right == NULL)
|
|
goto done;
|
|
/* Guaranteed to be */
|
|
if (lmp->is[0] != '\0' && rmp->is[0] != '\0')
|
|
{
|
|
lmp->is = icatalloc(lmp->is, rmp->is);
|
|
if (lmp->is == NULL)
|
|
goto done;
|
|
}
|
|
else
|
|
lmp->is[0] = '\0';
|
|
}
|
|
break;
|
|
default:
|
|
if (t < END)
|
|
{
|
|
/* "cannot happen" */
|
|
goto done;
|
|
}
|
|
else if (t == '\0')
|
|
{
|
|
/* not on *my* shift */
|
|
goto done;
|
|
}
|
|
else if (t >= CSET
|
|
#ifdef MBS_SUPPORT
|
|
|| t == ANYCHAR
|
|
|| t == MBCSET
|
|
#endif /* MBS_SUPPORT */
|
|
)
|
|
{
|
|
/* easy enough */
|
|
resetmust(mp);
|
|
}
|
|
else
|
|
{
|
|
/* plain character */
|
|
resetmust(mp);
|
|
mp->is[0] = mp->left[0] = mp->right[0] = t;
|
|
mp->is[1] = mp->left[1] = mp->right[1] = '\0';
|
|
mp->in = enlist(mp->in, mp->is, (size_t)1);
|
|
if (mp->in == NULL)
|
|
goto done;
|
|
}
|
|
break;
|
|
}
|
|
#ifdef DEBUG
|
|
fprintf(stderr, " node: %d:", ri);
|
|
prtok(dfa->tokens[ri]);
|
|
fprintf(stderr, "\n in:");
|
|
for (i = 0; mp->in[i]; ++i)
|
|
fprintf(stderr, " \"%s\"", mp->in[i]);
|
|
fprintf(stderr, "\n is: \"%s\"\n", mp->is);
|
|
fprintf(stderr, " left: \"%s\"\n", mp->left);
|
|
fprintf(stderr, " right: \"%s\"\n", mp->right);
|
|
#endif
|
|
++mp;
|
|
}
|
|
done:
|
|
if (strlen(result))
|
|
{
|
|
dm = (struct dfamust *) malloc(sizeof (struct dfamust));
|
|
dm->exact = exact;
|
|
dm->must = malloc(strlen(result) + 1);
|
|
strcpy(dm->must, result);
|
|
dm->next = dfa->musts;
|
|
dfa->musts = dm;
|
|
}
|
|
mp = musts;
|
|
for (i = 0; i <= dfa->tindex; ++i)
|
|
{
|
|
freelist(mp[i].in);
|
|
ifree((char *) mp[i].in);
|
|
ifree(mp[i].left);
|
|
ifree(mp[i].right);
|
|
ifree(mp[i].is);
|
|
}
|
|
free((char *) mp);
|
|
}
|
|
/* vim:set shiftwidth=2: */
|