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/* Extended regular expression matching and search library.
Copyright (C) 2002-2007,2009,2010 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
static reg_errcode_t re_compile_internal (regex_t *preg, const char * pattern,
size_t length, reg_syntax_t syntax);
static void re_compile_fastmap_iter (regex_t *bufp,
const re_dfastate_t *init_state,
char *fastmap);
static reg_errcode_t init_dfa (re_dfa_t *dfa, size_t pat_len);
#ifdef RE_ENABLE_I18N
static void free_charset (re_charset_t *cset);
#endif /* RE_ENABLE_I18N */
static void free_workarea_compile (regex_t *preg);
static reg_errcode_t create_initial_state (re_dfa_t *dfa);
#ifdef RE_ENABLE_I18N
static void optimize_utf8 (re_dfa_t *dfa);
#endif
static reg_errcode_t analyze (regex_t *preg);
static reg_errcode_t preorder (bin_tree_t *root,
reg_errcode_t (fn (void *, bin_tree_t *)),
void *extra);
static reg_errcode_t postorder (bin_tree_t *root,
reg_errcode_t (fn (void *, bin_tree_t *)),
void *extra);
static reg_errcode_t optimize_subexps (void *extra, bin_tree_t *node);
static reg_errcode_t lower_subexps (void *extra, bin_tree_t *node);
static bin_tree_t *lower_subexp (reg_errcode_t *err, regex_t *preg,
bin_tree_t *node);
static reg_errcode_t calc_first (void *extra, bin_tree_t *node);
static reg_errcode_t calc_next (void *extra, bin_tree_t *node);
static reg_errcode_t link_nfa_nodes (void *extra, bin_tree_t *node);
static int duplicate_node (re_dfa_t *dfa, int org_idx, unsigned int constraint);
static int search_duplicated_node (const re_dfa_t *dfa, int org_node,
unsigned int constraint);
static reg_errcode_t calc_eclosure (re_dfa_t *dfa);
static reg_errcode_t calc_eclosure_iter (re_node_set *new_set, re_dfa_t *dfa,
int node, int root);
static reg_errcode_t calc_inveclosure (re_dfa_t *dfa);
static int fetch_number (re_string_t *input, re_token_t *token,
reg_syntax_t syntax);
static int peek_token (re_token_t *token, re_string_t *input,
reg_syntax_t syntax) internal_function;
static bin_tree_t *parse (re_string_t *regexp, regex_t *preg,
reg_syntax_t syntax, reg_errcode_t *err);
static bin_tree_t *parse_reg_exp (re_string_t *regexp, regex_t *preg,
re_token_t *token, reg_syntax_t syntax,
int nest, reg_errcode_t *err);
static bin_tree_t *parse_branch (re_string_t *regexp, regex_t *preg,
re_token_t *token, reg_syntax_t syntax,
int nest, reg_errcode_t *err);
static bin_tree_t *parse_expression (re_string_t *regexp, regex_t *preg,
re_token_t *token, reg_syntax_t syntax,
int nest, reg_errcode_t *err);
static bin_tree_t *parse_sub_exp (re_string_t *regexp, regex_t *preg,
re_token_t *token, reg_syntax_t syntax,
int nest, reg_errcode_t *err);
static bin_tree_t *parse_dup_op (bin_tree_t *dup_elem, re_string_t *regexp,
re_dfa_t *dfa, re_token_t *token,
reg_syntax_t syntax, reg_errcode_t *err);
static bin_tree_t *parse_bracket_exp (re_string_t *regexp, re_dfa_t *dfa,
re_token_t *token, reg_syntax_t syntax,
reg_errcode_t *err);
static reg_errcode_t parse_bracket_element (bracket_elem_t *elem,
re_string_t *regexp,
re_token_t *token, int token_len,
re_dfa_t *dfa,
reg_syntax_t syntax,
int accept_hyphen);
static reg_errcode_t parse_bracket_symbol (bracket_elem_t *elem,
re_string_t *regexp,
re_token_t *token);
#ifdef RE_ENABLE_I18N
static reg_errcode_t build_equiv_class (bitset_t sbcset,
re_charset_t *mbcset,
int *equiv_class_alloc,
const unsigned char *name);
static reg_errcode_t build_charclass (RE_TRANSLATE_TYPE trans,
bitset_t sbcset,
re_charset_t *mbcset,
int *char_class_alloc,
const char *class_name,
reg_syntax_t syntax);
#else /* not RE_ENABLE_I18N */
static reg_errcode_t build_equiv_class (bitset_t sbcset,
const unsigned char *name);
static reg_errcode_t build_charclass (RE_TRANSLATE_TYPE trans,
bitset_t sbcset,
const char *class_name,
reg_syntax_t syntax);
#endif /* not RE_ENABLE_I18N */
static bin_tree_t *build_charclass_op (re_dfa_t *dfa,
RE_TRANSLATE_TYPE trans,
const char *class_name,
const char *extra,
int non_match, reg_errcode_t *err);
static bin_tree_t *create_tree (re_dfa_t *dfa,
bin_tree_t *left, bin_tree_t *right,
re_token_type_t type);
static bin_tree_t *create_token_tree (re_dfa_t *dfa,
bin_tree_t *left, bin_tree_t *right,
const re_token_t *token);
static bin_tree_t *duplicate_tree (const bin_tree_t *src, re_dfa_t *dfa);
static void free_token (re_token_t *node);
static reg_errcode_t free_tree (void *extra, bin_tree_t *node);
static reg_errcode_t mark_opt_subexp (void *extra, bin_tree_t *node);
/* This table gives an error message for each of the error codes listed
in regex.h. Obviously the order here has to be same as there.
POSIX doesn't require that we do anything for REG_NOERROR,
but why not be nice? */
const char __re_error_msgid[] attribute_hidden =
{
#define REG_NOERROR_IDX 0
gettext_noop ("Success") /* REG_NOERROR */
"\0"
#define REG_NOMATCH_IDX (REG_NOERROR_IDX + sizeof "Success")
gettext_noop ("No match") /* REG_NOMATCH */
"\0"
#define REG_BADPAT_IDX (REG_NOMATCH_IDX + sizeof "No match")
gettext_noop ("Invalid regular expression") /* REG_BADPAT */
"\0"
#define REG_ECOLLATE_IDX (REG_BADPAT_IDX + sizeof "Invalid regular expression")
gettext_noop ("Invalid collation character") /* REG_ECOLLATE */
"\0"
#define REG_ECTYPE_IDX (REG_ECOLLATE_IDX + sizeof "Invalid collation character")
gettext_noop ("Invalid character class name") /* REG_ECTYPE */
"\0"
#define REG_EESCAPE_IDX (REG_ECTYPE_IDX + sizeof "Invalid character class name")
gettext_noop ("Trailing backslash") /* REG_EESCAPE */
"\0"
#define REG_ESUBREG_IDX (REG_EESCAPE_IDX + sizeof "Trailing backslash")
gettext_noop ("Invalid back reference") /* REG_ESUBREG */
"\0"
#define REG_EBRACK_IDX (REG_ESUBREG_IDX + sizeof "Invalid back reference")
gettext_noop ("Unmatched [ or [^") /* REG_EBRACK */
"\0"
#define REG_EPAREN_IDX (REG_EBRACK_IDX + sizeof "Unmatched [ or [^")
gettext_noop ("Unmatched ( or \\(") /* REG_EPAREN */
"\0"
#define REG_EBRACE_IDX (REG_EPAREN_IDX + sizeof "Unmatched ( or \\(")
gettext_noop ("Unmatched \\{") /* REG_EBRACE */
"\0"
#define REG_BADBR_IDX (REG_EBRACE_IDX + sizeof "Unmatched \\{")
gettext_noop ("Invalid content of \\{\\}") /* REG_BADBR */
"\0"
#define REG_ERANGE_IDX (REG_BADBR_IDX + sizeof "Invalid content of \\{\\}")
gettext_noop ("Invalid range end") /* REG_ERANGE */
"\0"
#define REG_ESPACE_IDX (REG_ERANGE_IDX + sizeof "Invalid range end")
gettext_noop ("Memory exhausted") /* REG_ESPACE */
"\0"
#define REG_BADRPT_IDX (REG_ESPACE_IDX + sizeof "Memory exhausted")
gettext_noop ("Invalid preceding regular expression") /* REG_BADRPT */
"\0"
#define REG_EEND_IDX (REG_BADRPT_IDX + sizeof "Invalid preceding regular expression")
gettext_noop ("Premature end of regular expression") /* REG_EEND */
"\0"
#define REG_ESIZE_IDX (REG_EEND_IDX + sizeof "Premature end of regular expression")
gettext_noop ("Regular expression too big") /* REG_ESIZE */
"\0"
#define REG_ERPAREN_IDX (REG_ESIZE_IDX + sizeof "Regular expression too big")
gettext_noop ("Unmatched ) or \\)") /* REG_ERPAREN */
};
const size_t __re_error_msgid_idx[] attribute_hidden =
{
REG_NOERROR_IDX,
REG_NOMATCH_IDX,
REG_BADPAT_IDX,
REG_ECOLLATE_IDX,
REG_ECTYPE_IDX,
REG_EESCAPE_IDX,
REG_ESUBREG_IDX,
REG_EBRACK_IDX,
REG_EPAREN_IDX,
REG_EBRACE_IDX,
REG_BADBR_IDX,
REG_ERANGE_IDX,
REG_ESPACE_IDX,
REG_BADRPT_IDX,
REG_EEND_IDX,
REG_ESIZE_IDX,
REG_ERPAREN_IDX
};
/* Entry points for GNU code. */
#ifdef ZOS_USS
/* For ZOS USS we must define btowc */
wchar_t
btowc (int c)
{
wchar_t wtmp[2];
char tmp[2];
tmp[0] = c;
tmp[1] = 0;
mbtowc (wtmp, tmp, 1);
return wtmp[0];
}
#endif
/* re_compile_pattern is the GNU regular expression compiler: it
compiles PATTERN (of length LENGTH) and puts the result in BUFP.
Returns 0 if the pattern was valid, otherwise an error string.
Assumes the `allocated' (and perhaps `buffer') and `translate' fields
are set in BUFP on entry. */
const char *
re_compile_pattern (const char *pattern,
size_t length,
struct re_pattern_buffer *bufp)
{
reg_errcode_t ret;
/* And GNU code determines whether or not to get register information
by passing null for the REGS argument to re_match, etc., not by
setting no_sub, unless RE_NO_SUB is set. */
bufp->no_sub = !!(re_syntax_options & RE_NO_SUB);
/* Match anchors at newline. */
bufp->newline_anchor = 1;
ret = re_compile_internal (bufp, pattern, length, re_syntax_options);
if (!ret)
return NULL;
return gettext (__re_error_msgid + __re_error_msgid_idx[(int) ret]);
}
#ifdef _LIBC
weak_alias (__re_compile_pattern, re_compile_pattern)
#endif
/* Set by `re_set_syntax' to the current regexp syntax to recognize. Can
also be assigned to arbitrarily: each pattern buffer stores its own
syntax, so it can be changed between regex compilations. */
/* This has no initializer because initialized variables in Emacs
become read-only after dumping. */
reg_syntax_t re_syntax_options;
/* Specify the precise syntax of regexps for compilation. This provides
for compatibility for various utilities which historically have
different, incompatible syntaxes.
The argument SYNTAX is a bit mask comprised of the various bits
defined in regex.h. We return the old syntax. */
reg_syntax_t
re_set_syntax (reg_syntax_t syntax)
{
reg_syntax_t ret = re_syntax_options;
re_syntax_options = syntax;
return ret;
}
#ifdef _LIBC
weak_alias (__re_set_syntax, re_set_syntax)
#endif
int
re_compile_fastmap (struct re_pattern_buffer *bufp)
{
re_dfa_t *dfa = (re_dfa_t *) bufp->buffer;
char *fastmap = bufp->fastmap;
memset (fastmap, '\0', sizeof (char) * SBC_MAX);
re_compile_fastmap_iter (bufp, dfa->init_state, fastmap);
if (dfa->init_state != dfa->init_state_word)
re_compile_fastmap_iter (bufp, dfa->init_state_word, fastmap);
if (dfa->init_state != dfa->init_state_nl)
re_compile_fastmap_iter (bufp, dfa->init_state_nl, fastmap);
if (dfa->init_state != dfa->init_state_begbuf)
re_compile_fastmap_iter (bufp, dfa->init_state_begbuf, fastmap);
bufp->fastmap_accurate = 1;
return 0;
}
#ifdef _LIBC
weak_alias (__re_compile_fastmap, re_compile_fastmap)
#endif
static inline void
__attribute ((always_inline))
re_set_fastmap (char *fastmap, int icase, int ch)
{
fastmap[ch] = 1;
if (icase)
fastmap[tolower (ch)] = 1;
}
/* Helper function for re_compile_fastmap.
Compile fastmap for the initial_state INIT_STATE. */
static void
re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,
char *fastmap)
{
volatile re_dfa_t *dfa = (re_dfa_t *) bufp->buffer;
int node_cnt;
int icase = (dfa->mb_cur_max == 1 && (bufp->syntax & RE_ICASE));
for (node_cnt = 0; node_cnt < init_state->nodes.nelem; ++node_cnt)
{
int node = init_state->nodes.elems[node_cnt];
re_token_type_t type = dfa->nodes[node].type;
if (type == CHARACTER)
{
re_set_fastmap (fastmap, icase, dfa->nodes[node].opr.c);
#ifdef RE_ENABLE_I18N
if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)
{
unsigned char *buf = re_malloc (unsigned char, dfa->mb_cur_max), *p;
wchar_t wc;
mbstate_t state;
p = buf;
*p++ = dfa->nodes[node].opr.c;
while (++node < dfa->nodes_len
&& dfa->nodes[node].type == CHARACTER
&& dfa->nodes[node].mb_partial)
*p++ = dfa->nodes[node].opr.c;
memset (&state, '\0', sizeof (state));
if (__mbrtowc (&wc, (const char *) buf, p - buf,
&state) == p - buf
&& (__wcrtomb ((char *) buf, towlower (wc), &state)
!= (size_t) -1))
re_set_fastmap (fastmap, 0, buf[0]);
re_free (buf);
}
#endif
}
else if (type == SIMPLE_BRACKET)
{
int i, ch;
for (i = 0, ch = 0; i < BITSET_WORDS; ++i)
{
int j;
bitset_word_t w = dfa->nodes[node].opr.sbcset[i];
for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
if (w & ((bitset_word_t) 1 << j))
re_set_fastmap (fastmap, icase, ch);
}
}
#ifdef RE_ENABLE_I18N
else if (type == COMPLEX_BRACKET)
{
re_charset_t *cset = dfa->nodes[node].opr.mbcset;
int i;
# ifdef _LIBC
/* See if we have to try all bytes which start multiple collation
elements.
e.g. In da_DK, we want to catch 'a' since "aa" is a valid
collation element, and don't catch 'b' since 'b' is
the only collation element which starts from 'b' (and
it is caught by SIMPLE_BRACKET). */
if (_NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES) != 0
&& (cset->ncoll_syms || cset->nranges))
{
const int32_t *table = (const int32_t *)
_NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
for (i = 0; i < SBC_MAX; ++i)
if (table[i] < 0)
re_set_fastmap (fastmap, icase, i);
}
# endif /* _LIBC */
/* See if we have to start the match at all multibyte characters,
i.e. where we would not find an invalid sequence. This only
applies to multibyte character sets; for single byte character
sets, the SIMPLE_BRACKET again suffices. */
if (dfa->mb_cur_max > 1
&& (cset->nchar_classes || cset->non_match || cset->nranges
# ifdef _LIBC
|| cset->nequiv_classes
# endif /* _LIBC */
))
{
unsigned char c = 0;
do
{
mbstate_t mbs;
memset (&mbs, 0, sizeof (mbs));
if (__mbrtowc (NULL, (char *) &c, 1, &mbs) == (size_t) -2)
re_set_fastmap (fastmap, false, (int) c);
}
while (++c != 0);
}
else
{
/* ... Else catch all bytes which can start the mbchars. */
for (i = 0; i < cset->nmbchars; ++i)
{
char buf[256];
mbstate_t state;
memset (&state, '\0', sizeof (state));
if (__wcrtomb (buf, cset->mbchars[i], &state) != (size_t) -1)
re_set_fastmap (fastmap, icase, *(unsigned char *) buf);
if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)
{
if (__wcrtomb (buf, towlower (cset->mbchars[i]), &state)
!= (size_t) -1)
re_set_fastmap (fastmap, false, *(unsigned char *) buf);
}
}
}
}
#endif /* RE_ENABLE_I18N */
else if (type == OP_PERIOD
#ifdef RE_ENABLE_I18N
|| type == OP_UTF8_PERIOD
#endif /* RE_ENABLE_I18N */
|| type == END_OF_RE)
{
memset (fastmap, '\1', sizeof (char) * SBC_MAX);
if (type == END_OF_RE)
bufp->can_be_null = 1;
return;
}
}
}
/* Entry point for POSIX code. */
/* regcomp takes a regular expression as a string and compiles it.
PREG is a regex_t *. We do not expect any fields to be initialized,
since POSIX says we shouldn't. Thus, we set
`buffer' to the compiled pattern;
`used' to the length of the compiled pattern;
`syntax' to RE_SYNTAX_POSIX_EXTENDED if the
REG_EXTENDED bit in CFLAGS is set; otherwise, to
RE_SYNTAX_POSIX_BASIC;
`newline_anchor' to REG_NEWLINE being set in CFLAGS;
`fastmap' to an allocated space for the fastmap;
`fastmap_accurate' to zero;
`re_nsub' to the number of subexpressions in PATTERN.
PATTERN is the address of the pattern string.
CFLAGS is a series of bits which affect compilation.
If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
use POSIX basic syntax.
If REG_NEWLINE is set, then . and [^...] don't match newline.
Also, regexec will try a match beginning after every newline.
If REG_ICASE is set, then we considers upper- and lowercase
versions of letters to be equivalent when matching.
If REG_NOSUB is set, then when PREG is passed to regexec, that
routine will report only success or failure, and nothing about the
registers.
It returns 0 if it succeeds, nonzero if it doesn't. (See regex.h for
the return codes and their meanings.) */
int
regcomp (regex_t *__restrict preg,
const char *__restrict pattern,
int cflags)
{
reg_errcode_t ret;
reg_syntax_t syntax = ((cflags & REG_EXTENDED) ? RE_SYNTAX_POSIX_EXTENDED
: RE_SYNTAX_POSIX_BASIC);
preg->buffer = NULL;
preg->allocated = 0;
preg->used = 0;
/* Try to allocate space for the fastmap. */
preg->fastmap = re_malloc (char, SBC_MAX);
if (BE (preg->fastmap == NULL, 0))
return REG_ESPACE;
syntax |= (cflags & REG_ICASE) ? RE_ICASE : 0;
/* If REG_NEWLINE is set, newlines are treated differently. */
if (cflags & REG_NEWLINE)
{ /* REG_NEWLINE implies neither . nor [^...] match newline. */
syntax &= ~RE_DOT_NEWLINE;
syntax |= RE_HAT_LISTS_NOT_NEWLINE;
/* It also changes the matching behavior. */
preg->newline_anchor = 1;
}
else
preg->newline_anchor = 0;
preg->no_sub = !!(cflags & REG_NOSUB);
preg->translate = NULL;
ret = re_compile_internal (preg, pattern, strlen (pattern), syntax);
/* POSIX doesn't distinguish between an unmatched open-group and an
unmatched close-group: both are REG_EPAREN. */
if (ret == REG_ERPAREN)
ret = REG_EPAREN;
/* We have already checked preg->fastmap != NULL. */
if (BE (ret == REG_NOERROR, 1))
/* Compute the fastmap now, since regexec cannot modify the pattern
buffer. This function never fails in this implementation. */
(void) re_compile_fastmap (preg);
else
{
/* Some error occurred while compiling the expression. */
re_free (preg->fastmap);
preg->fastmap = NULL;
}
return (int) ret;
}
#ifdef _LIBC
weak_alias (__regcomp, regcomp)
#endif
/* Returns a message corresponding to an error code, ERRCODE, returned
from either regcomp or regexec. We don't use PREG here. */
size_t
regerror(int errcode, const regex_t *__restrict preg,
char *__restrict errbuf, size_t errbuf_size)
{
const char *msg;
size_t msg_size;
if (BE (errcode < 0
|| errcode >= (int) (sizeof (__re_error_msgid_idx)
/ sizeof (__re_error_msgid_idx[0])), 0))
/* Only error codes returned by the rest of the code should be passed
to this routine. If we are given anything else, or if other regex
code generates an invalid error code, then the program has a bug.
Dump core so we can fix it. */
abort ();
msg = gettext (__re_error_msgid + __re_error_msgid_idx[errcode]);
msg_size = strlen (msg) + 1; /* Includes the null. */
if (BE (errbuf_size != 0, 1))
{
if (BE (msg_size > errbuf_size, 0))
{
memcpy (errbuf, msg, errbuf_size - 1);
errbuf[errbuf_size - 1] = 0;
}
else
memcpy (errbuf, msg, msg_size);
}
return msg_size;
}
#ifdef _LIBC
weak_alias (__regerror, regerror)
#endif
#ifdef RE_ENABLE_I18N
/* This static array is used for the map to single-byte characters when
UTF-8 is used. Otherwise we would allocate memory just to initialize
it the same all the time. UTF-8 is the preferred encoding so this is
a worthwhile optimization. */
#if __GNUC__ >= 3
static const bitset_t utf8_sb_map = {
/* Set the first 128 bits. */
[0 ... 0x80 / BITSET_WORD_BITS - 1] = BITSET_WORD_MAX
};
#else /* ! (__GNUC__ >= 3) */
static bitset_t utf8_sb_map;
#endif /* __GNUC__ >= 3 */
#endif /* RE_ENABLE_I18N */
static void
free_dfa_content (re_dfa_t *dfa)
{
int i, j;
if (dfa->nodes)
for (i = 0; i < dfa->nodes_len; ++i)
free_token (dfa->nodes + i);
re_free (dfa->nexts);
for (i = 0; i < dfa->nodes_len; ++i)
{
if (dfa->eclosures != NULL)
re_node_set_free (dfa->eclosures + i);
if (dfa->inveclosures != NULL)
re_node_set_free (dfa->inveclosures + i);
if (dfa->edests != NULL)
re_node_set_free (dfa->edests + i);
}
re_free (dfa->edests);
re_free (dfa->eclosures);
re_free (dfa->inveclosures);
re_free (dfa->nodes);
if (dfa->state_table)
for (i = 0; i <= dfa->state_hash_mask; ++i)
{
struct re_state_table_entry *entry = dfa->state_table + i;
for (j = 0; j < entry->num; ++j)
{
re_dfastate_t *state = entry->array[j];
free_state (state);
}
re_free (entry->array);
}
re_free (dfa->state_table);
#ifdef RE_ENABLE_I18N
if (dfa->sb_char != utf8_sb_map)
re_free (dfa->sb_char);
#endif
re_free (dfa->subexp_map);
#ifdef DEBUG
re_free (dfa->re_str);
#endif
re_free (dfa);
}
/* Free dynamically allocated space used by PREG. */
void
regfree (regex_t *preg)
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
if (BE (dfa != NULL, 1))
free_dfa_content (dfa);
preg->buffer = NULL;
preg->allocated = 0;
re_free (preg->fastmap);
preg->fastmap = NULL;
re_free (preg->translate);
preg->translate = NULL;
}
#ifdef _LIBC
weak_alias (__regfree, regfree)
#endif
/* Entry points compatible with 4.2 BSD regex library. We don't define
them unless specifically requested. */
#if defined _REGEX_RE_COMP || defined _LIBC
/* BSD has one and only one pattern buffer. */
static struct re_pattern_buffer re_comp_buf;
char *
# ifdef _LIBC
/* Make these definitions weak in libc, so POSIX programs can redefine
these names if they don't use our functions, and still use
regcomp/regexec above without link errors. */
weak_function
# endif
re_comp (s)
const char *s;
{
reg_errcode_t ret;
char *fastmap;
if (!s)
{
if (!re_comp_buf.buffer)
return gettext ("No previous regular expression");
return 0;
}
if (re_comp_buf.buffer)
{
fastmap = re_comp_buf.fastmap;
re_comp_buf.fastmap = NULL;
__regfree (&re_comp_buf);
memset (&re_comp_buf, '\0', sizeof (re_comp_buf));
re_comp_buf.fastmap = fastmap;
}
if (re_comp_buf.fastmap == NULL)
{
re_comp_buf.fastmap = (char *) malloc (SBC_MAX);
if (re_comp_buf.fastmap == NULL)
return (char *) gettext (__re_error_msgid
+ __re_error_msgid_idx[(int) REG_ESPACE]);
}
/* Since `re_exec' always passes NULL for the `regs' argument, we
don't need to initialize the pattern buffer fields which affect it. */
/* Match anchors at newlines. */
re_comp_buf.newline_anchor = 1;
ret = re_compile_internal (&re_comp_buf, s, strlen (s), re_syntax_options);
if (!ret)
return NULL;
/* Yes, we're discarding `const' here if !HAVE_LIBINTL. */
return (char *) gettext (__re_error_msgid + __re_error_msgid_idx[(int) ret]);
}
#ifdef _LIBC
libc_freeres_fn (free_mem)
{
__regfree (&re_comp_buf);
}
#endif
#endif /* _REGEX_RE_COMP */
/* Internal entry point.
Compile the regular expression PATTERN, whose length is LENGTH.
SYNTAX indicate regular expression's syntax. */
static reg_errcode_t
re_compile_internal (regex_t *preg, const char * pattern, size_t length,
reg_syntax_t syntax)
{
reg_errcode_t err = REG_NOERROR;
re_dfa_t *dfa;
re_string_t regexp;
/* Initialize the pattern buffer. */
preg->fastmap_accurate = 0;
preg->syntax = syntax;
preg->not_bol = preg->not_eol = 0;
preg->used = 0;
preg->re_nsub = 0;
preg->can_be_null = 0;
preg->regs_allocated = REGS_UNALLOCATED;
/* Initialize the dfa. */
dfa = (re_dfa_t *) preg->buffer;
if (BE (preg->allocated < sizeof (re_dfa_t), 0))
{
/* If zero allocated, but buffer is non-null, try to realloc
enough space. This loses if buffer's address is bogus, but
that is the user's responsibility. If ->buffer is NULL this
is a simple allocation. */
dfa = re_realloc (preg->buffer, re_dfa_t, 1);
if (dfa == NULL)
return REG_ESPACE;
preg->allocated = sizeof (re_dfa_t);
preg->buffer = (unsigned char *) dfa;
}
preg->used = sizeof (re_dfa_t);
err = init_dfa (dfa, length);
if (BE (err != REG_NOERROR, 0))
{
free_dfa_content (dfa);
preg->buffer = NULL;
preg->allocated = 0;
return err;
}
#ifdef DEBUG
/* Note: length+1 will not overflow since it is checked in init_dfa. */
dfa->re_str = re_malloc (char, length + 1);
strncpy (dfa->re_str, pattern, length + 1);
#endif
__libc_lock_init (dfa->lock);
err = re_string_construct (&regexp, pattern, length, preg->translate,
syntax & RE_ICASE, dfa);
if (BE (err != REG_NOERROR, 0))
{
re_compile_internal_free_return:
free_workarea_compile (preg);
re_string_destruct (&regexp);
free_dfa_content (dfa);
preg->buffer = NULL;
preg->allocated = 0;
return err;
}
/* Parse the regular expression, and build a structure tree. */
preg->re_nsub = 0;
dfa->str_tree = parse (&regexp, preg, syntax, &err);
if (BE (dfa->str_tree == NULL, 0))
goto re_compile_internal_free_return;
/* Analyze the tree and create the nfa. */
err = analyze (preg);
if (BE (err != REG_NOERROR, 0))
goto re_compile_internal_free_return;
#ifdef RE_ENABLE_I18N
/* If possible, do searching in single byte encoding to speed things up. */
if (dfa->is_utf8 && !(syntax & RE_ICASE) && preg->translate == NULL)
optimize_utf8 (dfa);
#endif
/* Then create the initial state of the dfa. */
err = create_initial_state (dfa);
/* Release work areas. */
free_workarea_compile (preg);
re_string_destruct (&regexp);
if (BE (err != REG_NOERROR, 0))
{
free_dfa_content (dfa);
preg->buffer = NULL;
preg->allocated = 0;
}
return err;
}
/* Initialize DFA. We use the length of the regular expression PAT_LEN
as the initial length of some arrays. */
static reg_errcode_t
init_dfa (re_dfa_t *dfa, size_t pat_len)
{
unsigned int table_size;
#ifndef _LIBC
char *codeset_name;
#endif
memset (dfa, '\0', sizeof (re_dfa_t));
/* Force allocation of str_tree_storage the first time. */
dfa->str_tree_storage_idx = BIN_TREE_STORAGE_SIZE;
/* Avoid overflows. */
if (pat_len == SIZE_MAX)
return REG_ESPACE;
dfa->nodes_alloc = pat_len + 1;
dfa->nodes = re_malloc (re_token_t, dfa->nodes_alloc);
/* table_size = 2 ^ ceil(log pat_len) */
for (table_size = 1; ; table_size <<= 1)
if (table_size > pat_len)
break;
dfa->state_table = calloc (sizeof (struct re_state_table_entry), table_size);
dfa->state_hash_mask = table_size - 1;
dfa->mb_cur_max = MB_CUR_MAX;
#ifdef _LIBC
if (dfa->mb_cur_max == 6
&& strcmp (_NL_CURRENT (LC_CTYPE, _NL_CTYPE_CODESET_NAME), "UTF-8") == 0)
dfa->is_utf8 = 1;
dfa->map_notascii = (_NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_MAP_TO_NONASCII)
!= 0);
#else
# ifdef HAVE_LANGINFO_CODESET
codeset_name = nl_langinfo (CODESET);
# else
codeset_name = getenv ("LC_ALL");
if (codeset_name == NULL || codeset_name[0] == '\0')
codeset_name = getenv ("LC_CTYPE");
if (codeset_name == NULL || codeset_name[0] == '\0')
codeset_name = getenv ("LANG");
if (codeset_name == NULL)
codeset_name = "";
else if (strchr (codeset_name, '.') != NULL)
codeset_name = strchr (codeset_name, '.') + 1;
# endif
/* strcasecmp isn't a standard interface. brute force check */
#if 0
if (strcasecmp (codeset_name, "UTF-8") == 0
|| strcasecmp (codeset_name, "UTF8") == 0)
dfa->is_utf8 = 1;
#else
if ( (codeset_name[0] == 'U' || codeset_name[0] == 'u')
&& (codeset_name[1] == 'T' || codeset_name[1] == 't')
&& (codeset_name[2] == 'F' || codeset_name[2] == 'f')
&& (codeset_name[3] == '-'
? codeset_name[4] == '8' && codeset_name[5] == '\0'
: codeset_name[3] == '8' && codeset_name[4] == '\0'))
dfa->is_utf8 = 1;
#endif
/* We check exhaustively in the loop below if this charset is a
superset of ASCII. */
dfa->map_notascii = 0;
#endif
#ifdef RE_ENABLE_I18N
if (dfa->mb_cur_max > 1)
{
if (dfa->is_utf8)
{
#if !defined(__GNUC__) || __GNUC__ < 3
static short utf8_sb_map_inited = 0;
if (! utf8_sb_map_inited)
{
int i;
utf8_sb_map_inited = 0;
for (i = 0; i <= 0x80 / BITSET_WORD_BITS - 1; i++)
utf8_sb_map[i] = BITSET_WORD_MAX;
}
#endif
dfa->sb_char = (re_bitset_ptr_t) utf8_sb_map;
}
else
{
int i, j, ch;
dfa->sb_char = (re_bitset_ptr_t) calloc (sizeof (bitset_t), 1);
if (BE (dfa->sb_char == NULL, 0))
return REG_ESPACE;
/* Set the bits corresponding to single byte chars. */
for (i = 0, ch = 0; i < BITSET_WORDS; ++i)
for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
{
wint_t wch = __btowc (ch);
if (wch != WEOF)
dfa->sb_char[i] |= (bitset_word_t) 1 << j;
# ifndef _LIBC
if (isascii (ch) && wch != ch)
dfa->map_notascii = 1;
# endif
}
}
}
#endif
if (BE (dfa->nodes == NULL || dfa->state_table == NULL, 0))
return REG_ESPACE;
return REG_NOERROR;
}
/* Initialize WORD_CHAR table, which indicate which character is
"word". In this case "word" means that it is the word construction
character used by some operators like "\<", "\>", etc. */
static void
internal_function
init_word_char (re_dfa_t *dfa)
{
int i, j, ch;
dfa->word_ops_used = 1;
for (i = 0, ch = 0; i < BITSET_WORDS; ++i)
for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
if (isalnum (ch) || ch == '_')
dfa->word_char[i] |= (bitset_word_t) 1 << j;
}
/* Free the work area which are only used while compiling. */
static void
free_workarea_compile (regex_t *preg)
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
bin_tree_storage_t *storage, *next;
for (storage = dfa->str_tree_storage; storage; storage = next)
{
next = storage->next;
re_free (storage);
}
dfa->str_tree_storage = NULL;
dfa->str_tree_storage_idx = BIN_TREE_STORAGE_SIZE;
dfa->str_tree = NULL;
re_free (dfa->org_indices);
dfa->org_indices = NULL;
}
/* Create initial states for all contexts. */
static reg_errcode_t
create_initial_state (re_dfa_t *dfa)
{
int first, i;
reg_errcode_t err;
re_node_set init_nodes;
/* Initial states have the epsilon closure of the node which is
the first node of the regular expression. */
first = dfa->str_tree->first->node_idx;
dfa->init_node = first;
err = re_node_set_init_copy (&init_nodes, dfa->eclosures + first);
if (BE (err != REG_NOERROR, 0))
return err;
/* The back-references which are in initial states can epsilon transit,
since in this case all of the subexpressions can be null.
Then we add epsilon closures of the nodes which are the next nodes of
the back-references. */
if (dfa->nbackref > 0)
for (i = 0; i < init_nodes.nelem; ++i)
{
int node_idx = init_nodes.elems[i];
re_token_type_t type = dfa->nodes[node_idx].type;
int clexp_idx;
if (type != OP_BACK_REF)
continue;
for (clexp_idx = 0; clexp_idx < init_nodes.nelem; ++clexp_idx)
{
re_token_t *clexp_node;
clexp_node = dfa->nodes + init_nodes.elems[clexp_idx];
if (clexp_node->type == OP_CLOSE_SUBEXP
&& clexp_node->opr.idx == dfa->nodes[node_idx].opr.idx)
break;
}
if (clexp_idx == init_nodes.nelem)
continue;
if (type == OP_BACK_REF)
{
int dest_idx = dfa->edests[node_idx].elems[0];
if (!re_node_set_contains (&init_nodes, dest_idx))
{
reg_errcode_t err = re_node_set_merge (&init_nodes,
dfa->eclosures
+ dest_idx);
if (err != REG_NOERROR)
return err;
i = 0;
}
}
}
/* It must be the first time to invoke acquire_state. */
dfa->init_state = re_acquire_state_context (&err, dfa, &init_nodes, 0);
/* We don't check ERR here, since the initial state must not be NULL. */
if (BE (dfa->init_state == NULL, 0))
return err;
if (dfa->init_state->has_constraint)
{
dfa->init_state_word = re_acquire_state_context (&err, dfa, &init_nodes,
CONTEXT_WORD);
dfa->init_state_nl = re_acquire_state_context (&err, dfa, &init_nodes,
CONTEXT_NEWLINE);
dfa->init_state_begbuf = re_acquire_state_context (&err, dfa,
&init_nodes,
CONTEXT_NEWLINE
| CONTEXT_BEGBUF);
if (BE (dfa->init_state_word == NULL || dfa->init_state_nl == NULL
|| dfa->init_state_begbuf == NULL, 0))
return err;
}
else
dfa->init_state_word = dfa->init_state_nl
= dfa->init_state_begbuf = dfa->init_state;
re_node_set_free (&init_nodes);
return REG_NOERROR;
}
#ifdef RE_ENABLE_I18N
/* If it is possible to do searching in single byte encoding instead of UTF-8
to speed things up, set dfa->mb_cur_max to 1, clear is_utf8 and change
DFA nodes where needed. */
static void
optimize_utf8 (re_dfa_t *dfa)
{
int node, i, mb_chars = 0, has_period = 0;
for (node = 0; node < dfa->nodes_len; ++node)
switch (dfa->nodes[node].type)
{
case CHARACTER:
if (dfa->nodes[node].opr.c >= 0x80)
mb_chars = 1;
break;
case ANCHOR:
switch (dfa->nodes[node].opr.ctx_type)
{
case LINE_FIRST:
case LINE_LAST:
case BUF_FIRST:
case BUF_LAST:
break;
default:
/* Word anchors etc. cannot be handled. It's okay to test
opr.ctx_type since constraints (for all DFA nodes) are
created by ORing one or more opr.ctx_type values. */
return;
}
break;
case OP_PERIOD:
has_period = 1;
break;
case OP_BACK_REF:
case OP_ALT:
case END_OF_RE:
case OP_DUP_ASTERISK:
case OP_OPEN_SUBEXP:
case OP_CLOSE_SUBEXP:
break;
case COMPLEX_BRACKET:
return;
case SIMPLE_BRACKET:
/* Just double check. The non-ASCII range starts at 0x80. */
assert (0x80 % BITSET_WORD_BITS == 0);
for (i = 0x80 / BITSET_WORD_BITS; i < BITSET_WORDS; ++i)
if (dfa->nodes[node].opr.sbcset[i])
return;
break;
default:
abort ();
}
if (mb_chars || has_period)
for (node = 0; node < dfa->nodes_len; ++node)
{
if (dfa->nodes[node].type == CHARACTER
&& dfa->nodes[node].opr.c >= 0x80)
dfa->nodes[node].mb_partial = 0;
else if (dfa->nodes[node].type == OP_PERIOD)
dfa->nodes[node].type = OP_UTF8_PERIOD;
}
/* The search can be in single byte locale. */
dfa->mb_cur_max = 1;
dfa->is_utf8 = 0;
dfa->has_mb_node = dfa->nbackref > 0 || has_period;
}
#endif
/* Analyze the structure tree, and calculate "first", "next", "edest",
"eclosure", and "inveclosure". */
static reg_errcode_t
analyze (regex_t *preg)
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
reg_errcode_t ret;
/* Allocate arrays. */
dfa->nexts = re_malloc (int, dfa->nodes_alloc);
dfa->org_indices = re_malloc (int, dfa->nodes_alloc);
dfa->edests = re_malloc (re_node_set, dfa->nodes_alloc);
dfa->eclosures = re_malloc (re_node_set, dfa->nodes_alloc);
if (BE (dfa->nexts == NULL || dfa->org_indices == NULL || dfa->edests == NULL
|| dfa->eclosures == NULL, 0))
return REG_ESPACE;
dfa->subexp_map = re_malloc (int, preg->re_nsub);
if (dfa->subexp_map != NULL)
{
int i;
for (i = 0; i < preg->re_nsub; i++)
dfa->subexp_map[i] = i;
preorder (dfa->str_tree, optimize_subexps, dfa);
for (i = 0; i < preg->re_nsub; i++)
if (dfa->subexp_map[i] != i)
break;
if (i == preg->re_nsub)
{
free (dfa->subexp_map);
dfa->subexp_map = NULL;
}
}
ret = postorder (dfa->str_tree, lower_subexps, preg);
if (BE (ret != REG_NOERROR, 0))
return ret;
ret = postorder (dfa->str_tree, calc_first, dfa);
if (BE (ret != REG_NOERROR, 0))
return ret;
preorder (dfa->str_tree, calc_next, dfa);
ret = preorder (dfa->str_tree, link_nfa_nodes, dfa);
if (BE (ret != REG_NOERROR, 0))
return ret;
ret = calc_eclosure (dfa);
if (BE (ret != REG_NOERROR, 0))
return ret;
/* We only need this during the prune_impossible_nodes pass in regexec.c;
skip it if p_i_n will not run, as calc_inveclosure can be quadratic. */
if ((!preg->no_sub && preg->re_nsub > 0 && dfa->has_plural_match)
|| dfa->nbackref)
{
dfa->inveclosures = re_malloc (re_node_set, dfa->nodes_len);
if (BE (dfa->inveclosures == NULL, 0))
return REG_ESPACE;
ret = calc_inveclosure (dfa);
}
return ret;
}
/* Our parse trees are very unbalanced, so we cannot use a stack to
implement parse tree visits. Instead, we use parent pointers and
some hairy code in these two functions. */
static reg_errcode_t
postorder (bin_tree_t *root, reg_errcode_t (fn (void *, bin_tree_t *)),
void *extra)
{
bin_tree_t *node, *prev;
for (node = root; ; )
{
/* Descend down the tree, preferably to the left (or to the right
if that's the only child). */
while (node->left || node->right)
if (node->left)
node = node->left;
else
node = node->right;
do
{
reg_errcode_t err = fn (extra, node);
if (BE (err != REG_NOERROR, 0))
return err;
if (node->parent == NULL)
return REG_NOERROR;
prev = node;
node = node->parent;
}
/* Go up while we have a node that is reached from the right. */
while (node->right == prev || node->right == NULL);
node = node->right;
}
}
static reg_errcode_t
preorder (bin_tree_t *root, reg_errcode_t (fn (void *, bin_tree_t *)),
void *extra)
{
bin_tree_t *node;
for (node = root; ; )
{
reg_errcode_t err = fn (extra, node);
if (BE (err != REG_NOERROR, 0))
return err;
/* Go to the left node, or up and to the right. */
if (node->left)
node = node->left;
else
{
bin_tree_t *prev = NULL;
while (node->right == prev || node->right == NULL)
{
prev = node;
node = node->parent;
if (!node)
return REG_NOERROR;
}
node = node->right;
}
}
}
/* Optimization pass: if a SUBEXP is entirely contained, strip it and tell
re_search_internal to map the inner one's opr.idx to this one's. Adjust
backreferences as well. Requires a preorder visit. */
static reg_errcode_t
optimize_subexps (void *extra, bin_tree_t *node)
{
re_dfa_t *dfa = (re_dfa_t *) extra;
if (node->token.type == OP_BACK_REF && dfa->subexp_map)
{
int idx = node->token.opr.idx;
node->token.opr.idx = dfa->subexp_map[idx];
dfa->used_bkref_map |= 1 << node->token.opr.idx;
}
else if (node->token.type == SUBEXP
&& node->left && node->left->token.type == SUBEXP)
{
int other_idx = node->left->token.opr.idx;
node->left = node->left->left;
if (node->left)
node->left->parent = node;
dfa->subexp_map[other_idx] = dfa->subexp_map[node->token.opr.idx];
if (other_idx < BITSET_WORD_BITS)
dfa->used_bkref_map &= ~((bitset_word_t) 1 << other_idx);
}
return REG_NOERROR;
}
/* Lowering pass: Turn each SUBEXP node into the appropriate concatenation
of OP_OPEN_SUBEXP, the body of the SUBEXP (if any) and OP_CLOSE_SUBEXP. */
static reg_errcode_t
lower_subexps (void *extra, bin_tree_t *node)
{
regex_t *preg = (regex_t *) extra;
reg_errcode_t err = REG_NOERROR;
if (node->left && node->left->token.type == SUBEXP)
{
node->left = lower_subexp (&err, preg, node->left);
if (node->left)
node->left->parent = node;
}
if (node->right && node->right->token.type == SUBEXP)
{
node->right = lower_subexp (&err, preg, node->right);
if (node->right)
node->right->parent = node;
}
return err;
}
static bin_tree_t *
lower_subexp (reg_errcode_t *err, regex_t *preg, bin_tree_t *node)
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
bin_tree_t *body = node->left;
bin_tree_t *op, *cls, *tree1, *tree;
if (preg->no_sub
/* We do not optimize empty subexpressions, because otherwise we may
have bad CONCAT nodes with NULL children. This is obviously not
very common, so we do not lose much. An example that triggers
this case is the sed "script" /\(\)/x. */
&& node->left != NULL
&& (node->token.opr.idx >= BITSET_WORD_BITS
|| !(dfa->used_bkref_map
& ((bitset_word_t) 1 << node->token.opr.idx))))
return node->left;
/* Convert the SUBEXP node to the concatenation of an
OP_OPEN_SUBEXP, the contents, and an OP_CLOSE_SUBEXP. */
op = create_tree (dfa, NULL, NULL, OP_OPEN_SUBEXP);
cls = create_tree (dfa, NULL, NULL, OP_CLOSE_SUBEXP);
tree1 = body ? create_tree (dfa, body, cls, CONCAT) : cls;
tree = create_tree (dfa, op, tree1, CONCAT);
if (BE (tree == NULL || tree1 == NULL || op == NULL || cls == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
op->token.opr.idx = cls->token.opr.idx = node->token.opr.idx;
op->token.opt_subexp = cls->token.opt_subexp = node->token.opt_subexp;
return tree;
}
/* Pass 1 in building the NFA: compute FIRST and create unlinked automaton
nodes. Requires a postorder visit. */
static reg_errcode_t
calc_first (void *extra, bin_tree_t *node)
{
re_dfa_t *dfa = (re_dfa_t *) extra;
if (node->token.type == CONCAT)
{
node->first = node->left->first;
node->node_idx = node->left->node_idx;
}
else
{
node->first = node;
node->node_idx = re_dfa_add_node (dfa, node->token);
if (BE (node->node_idx == -1, 0))
return REG_ESPACE;
if (node->token.type == ANCHOR)
dfa->nodes[node->node_idx].constraint = node->token.opr.ctx_type;
}
return REG_NOERROR;
}
/* Pass 2: compute NEXT on the tree. Preorder visit. */
static reg_errcode_t
calc_next (void *extra, bin_tree_t *node)
{
switch (node->token.type)
{
case OP_DUP_ASTERISK:
node->left->next = node;
break;
case CONCAT:
node->left->next = node->right->first;
node->right->next = node->next;
break;
default:
if (node->left)
node->left->next = node->next;
if (node->right)
node->right->next = node->next;
break;
}
return REG_NOERROR;
}
/* Pass 3: link all DFA nodes to their NEXT node (any order will do). */
static reg_errcode_t
link_nfa_nodes (void *extra, bin_tree_t *node)
{
re_dfa_t *dfa = (re_dfa_t *) extra;
int idx = node->node_idx;
reg_errcode_t err = REG_NOERROR;
switch (node->token.type)
{
case CONCAT:
break;
case END_OF_RE:
assert (node->next == NULL);
break;
case OP_DUP_ASTERISK:
case OP_ALT:
{
int left, right;
dfa->has_plural_match = 1;
if (node->left != NULL)
left = node->left->first->node_idx;
else
left = node->next->node_idx;
if (node->right != NULL)
right = node->right->first->node_idx;
else
right = node->next->node_idx;
assert (left > -1);
assert (right > -1);
err = re_node_set_init_2 (dfa->edests + idx, left, right);
}
break;
case ANCHOR:
case OP_OPEN_SUBEXP:
case OP_CLOSE_SUBEXP:
err = re_node_set_init_1 (dfa->edests + idx, node->next->node_idx);
break;
case OP_BACK_REF:
dfa->nexts[idx] = node->next->node_idx;
if (node->token.type == OP_BACK_REF)
err = re_node_set_init_1 (dfa->edests + idx, dfa->nexts[idx]);
break;
default:
assert (!IS_EPSILON_NODE (node->token.type));
dfa->nexts[idx] = node->next->node_idx;
break;
}
return err;
}
/* Duplicate the epsilon closure of the node ROOT_NODE.
Note that duplicated nodes have constraint INIT_CONSTRAINT in addition
to their own constraint. */
static reg_errcode_t
internal_function
duplicate_node_closure (re_dfa_t *dfa, int top_org_node, int top_clone_node,
int root_node, unsigned int init_constraint)
{
int org_node, clone_node, ret;
unsigned int constraint = init_constraint;
for (org_node = top_org_node, clone_node = top_clone_node;;)
{
int org_dest, clone_dest;
if (dfa->nodes[org_node].type == OP_BACK_REF)
{
/* If the back reference epsilon-transit, its destination must
also have the constraint. Then duplicate the epsilon closure
of the destination of the back reference, and store it in
edests of the back reference. */
org_dest = dfa->nexts[org_node];
re_node_set_empty (dfa->edests + clone_node);
clone_dest = duplicate_node (dfa, org_dest, constraint);
if (BE (clone_dest == -1, 0))
return REG_ESPACE;
dfa->nexts[clone_node] = dfa->nexts[org_node];
ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
if (BE (ret < 0, 0))
return REG_ESPACE;
}
else if (dfa->edests[org_node].nelem == 0)
{
/* In case of the node can't epsilon-transit, don't duplicate the
destination and store the original destination as the
destination of the node. */
dfa->nexts[clone_node] = dfa->nexts[org_node];
break;
}
else if (dfa->edests[org_node].nelem == 1)
{
/* In case of the node can epsilon-transit, and it has only one
destination. */
org_dest = dfa->edests[org_node].elems[0];
re_node_set_empty (dfa->edests + clone_node);
/* If the node is root_node itself, it means the epsilon clsoure
has a loop. Then tie it to the destination of the root_node. */
if (org_node == root_node && clone_node != org_node)
{
ret = re_node_set_insert (dfa->edests + clone_node, org_dest);
if (BE (ret < 0, 0))
return REG_ESPACE;
break;
}
/* In case of the node has another constraint, add it. */
constraint |= dfa->nodes[org_node].constraint;
clone_dest = duplicate_node (dfa, org_dest, constraint);
if (BE (clone_dest == -1, 0))
return REG_ESPACE;
ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
if (BE (ret < 0, 0))
return REG_ESPACE;
}
else /* dfa->edests[org_node].nelem == 2 */
{
/* In case of the node can epsilon-transit, and it has two
destinations. In the bin_tree_t and DFA, that's '|' and '*'. */
org_dest = dfa->edests[org_node].elems[0];
re_node_set_empty (dfa->edests + clone_node);
/* Search for a duplicated node which satisfies the constraint. */
clone_dest = search_duplicated_node (dfa, org_dest, constraint);
if (clone_dest == -1)
{
/* There is no such duplicated node, create a new one. */
reg_errcode_t err;
clone_dest = duplicate_node (dfa, org_dest, constraint);
if (BE (clone_dest == -1, 0))
return REG_ESPACE;
ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
if (BE (ret < 0, 0))
return REG_ESPACE;
err = duplicate_node_closure (dfa, org_dest, clone_dest,
root_node, constraint);
if (BE (err != REG_NOERROR, 0))
return err;
}
else
{
/* There is a duplicated node which satisfies the constraint,
use it to avoid infinite loop. */
ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
if (BE (ret < 0, 0))
return REG_ESPACE;
}
org_dest = dfa->edests[org_node].elems[1];
clone_dest = duplicate_node (dfa, org_dest, constraint);
if (BE (clone_dest == -1, 0))
return REG_ESPACE;
ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
if (BE (ret < 0, 0))
return REG_ESPACE;
}
org_node = org_dest;
clone_node = clone_dest;
}
return REG_NOERROR;
}
/* Search for a node which is duplicated from the node ORG_NODE, and
satisfies the constraint CONSTRAINT. */
static int
search_duplicated_node (const re_dfa_t *dfa, int org_node,
unsigned int constraint)
{
int idx;
for (idx = dfa->nodes_len - 1; dfa->nodes[idx].duplicated && idx > 0; --idx)
{
if (org_node == dfa->org_indices[idx]
&& constraint == dfa->nodes[idx].constraint)
return idx; /* Found. */
}
return -1; /* Not found. */
}
/* Duplicate the node whose index is ORG_IDX and set the constraint CONSTRAINT.
Return the index of the new node, or -1 if insufficient storage is
available. */
static int
duplicate_node (re_dfa_t *dfa, int org_idx, unsigned int constraint)
{
int dup_idx = re_dfa_add_node (dfa, dfa->nodes[org_idx]);
if (BE (dup_idx != -1, 1))
{
dfa->nodes[dup_idx].constraint = constraint;
dfa->nodes[dup_idx].constraint |= dfa->nodes[org_idx].constraint;
dfa->nodes[dup_idx].duplicated = 1;
/* Store the index of the original node. */
dfa->org_indices[dup_idx] = org_idx;
}
return dup_idx;
}
static reg_errcode_t
calc_inveclosure (re_dfa_t *dfa)
{
int src, idx, ret;
for (idx = 0; idx < dfa->nodes_len; ++idx)
re_node_set_init_empty (dfa->inveclosures + idx);
for (src = 0; src < dfa->nodes_len; ++src)
{
int *elems = dfa->eclosures[src].elems;
for (idx = 0; idx < dfa->eclosures[src].nelem; ++idx)
{
ret = re_node_set_insert_last (dfa->inveclosures + elems[idx], src);
if (BE (ret == -1, 0))
return REG_ESPACE;
}
}
return REG_NOERROR;
}
/* Calculate "eclosure" for all the node in DFA. */
static reg_errcode_t
calc_eclosure (re_dfa_t *dfa)
{
int node_idx, incomplete;
#ifdef DEBUG
assert (dfa->nodes_len > 0);
#endif
incomplete = 0;
/* For each nodes, calculate epsilon closure. */
for (node_idx = 0; ; ++node_idx)
{
reg_errcode_t err;
re_node_set eclosure_elem;
if (node_idx == dfa->nodes_len)
{
if (!incomplete)
break;
incomplete = 0;
node_idx = 0;
}
#ifdef DEBUG
assert (dfa->eclosures[node_idx].nelem != -1);
#endif
/* If we have already calculated, skip it. */
if (dfa->eclosures[node_idx].nelem != 0)
continue;
/* Calculate epsilon closure of `node_idx'. */
err = calc_eclosure_iter (&eclosure_elem, dfa, node_idx, 1);
if (BE (err != REG_NOERROR, 0))
return err;
if (dfa->eclosures[node_idx].nelem == 0)
{
incomplete = 1;
re_node_set_free (&eclosure_elem);
}
}
return REG_NOERROR;
}
/* Calculate epsilon closure of NODE. */
static reg_errcode_t
calc_eclosure_iter (re_node_set *new_set, re_dfa_t *dfa, int node, int root)
{
reg_errcode_t err;
int i;
re_node_set eclosure;
int ret;
int incomplete = 0;
err = re_node_set_alloc (&eclosure, dfa->edests[node].nelem + 1);
if (BE (err != REG_NOERROR, 0))
return err;
/* This indicates that we are calculating this node now.
We reference this value to avoid infinite loop. */
dfa->eclosures[node].nelem = -1;
/* If the current node has constraints, duplicate all nodes
since they must inherit the constraints. */
if (dfa->nodes[node].constraint
&& dfa->edests[node].nelem
&& !dfa->nodes[dfa->edests[node].elems[0]].duplicated)
{
err = duplicate_node_closure (dfa, node, node, node,
dfa->nodes[node].constraint);
if (BE (err != REG_NOERROR, 0))
return err;
}
/* Expand each epsilon destination nodes. */
if (IS_EPSILON_NODE(dfa->nodes[node].type))
for (i = 0; i < dfa->edests[node].nelem; ++i)
{
re_node_set eclosure_elem;
int edest = dfa->edests[node].elems[i];
/* If calculating the epsilon closure of `edest' is in progress,
return intermediate result. */
if (dfa->eclosures[edest].nelem == -1)
{
incomplete = 1;
continue;
}
/* If we haven't calculated the epsilon closure of `edest' yet,
calculate now. Otherwise use calculated epsilon closure. */
if (dfa->eclosures[edest].nelem == 0)
{
err = calc_eclosure_iter (&eclosure_elem, dfa, edest, 0);
if (BE (err != REG_NOERROR, 0))
return err;
}
else
eclosure_elem = dfa->eclosures[edest];
/* Merge the epsilon closure of `edest'. */
err = re_node_set_merge (&eclosure, &eclosure_elem);
if (BE (err != REG_NOERROR, 0))
return err;
/* If the epsilon closure of `edest' is incomplete,
the epsilon closure of this node is also incomplete. */
if (dfa->eclosures[edest].nelem == 0)
{
incomplete = 1;
re_node_set_free (&eclosure_elem);
}
}
/* An epsilon closure includes itself. */
ret = re_node_set_insert (&eclosure, node);
if (BE (ret < 0, 0))
return REG_ESPACE;
if (incomplete && !root)
dfa->eclosures[node].nelem = 0;
else
dfa->eclosures[node] = eclosure;
*new_set = eclosure;
return REG_NOERROR;
}
/* Functions for token which are used in the parser. */
/* Fetch a token from INPUT.
We must not use this function inside bracket expressions. */
static void
internal_function
fetch_token (re_token_t *result, re_string_t *input, reg_syntax_t syntax)
{
re_string_skip_bytes (input, peek_token (result, input, syntax));
}
/* Peek a token from INPUT, and return the length of the token.
We must not use this function inside bracket expressions. */
static int
internal_function
peek_token (re_token_t *token, re_string_t *input, reg_syntax_t syntax)
{
unsigned char c;
if (re_string_eoi (input))
{
token->type = END_OF_RE;
return 0;
}
c = re_string_peek_byte (input, 0);
token->opr.c = c;
token->word_char = 0;
#ifdef RE_ENABLE_I18N
token->mb_partial = 0;
if (input->mb_cur_max > 1 &&
!re_string_first_byte (input, re_string_cur_idx (input)))
{
token->type = CHARACTER;
token->mb_partial = 1;
return 1;
}
#endif
if (c == '\\')
{
unsigned char c2;
if (re_string_cur_idx (input) + 1 >= re_string_length (input))
{
token->type = BACK_SLASH;
return 1;
}
c2 = re_string_peek_byte_case (input, 1);
token->opr.c = c2;
token->type = CHARACTER;
#ifdef RE_ENABLE_I18N
if (input->mb_cur_max > 1)
{
wint_t wc = re_string_wchar_at (input,
re_string_cur_idx (input) + 1);
token->word_char = IS_WIDE_WORD_CHAR (wc) != 0;
}
else
#endif
token->word_char = IS_WORD_CHAR (c2) != 0;
switch (c2)
{
case '|':
if (!(syntax & RE_LIMITED_OPS) && !(syntax & RE_NO_BK_VBAR))
token->type = OP_ALT;
break;
case '1': case '2': case '3': case '4': case '5':
case '6': case '7': case '8': case '9':
if (!(syntax & RE_NO_BK_REFS))
{
token->type = OP_BACK_REF;
token->opr.idx = c2 - '1';
}
break;
case '<':
if (!(syntax & RE_NO_GNU_OPS))
{
token->type = ANCHOR;
token->opr.ctx_type = WORD_FIRST;
}
break;
case '>':
if (!(syntax & RE_NO_GNU_OPS))
{
token->type = ANCHOR;
token->opr.ctx_type = WORD_LAST;
}
break;
case 'b':
if (!(syntax & RE_NO_GNU_OPS))
{
token->type = ANCHOR;
token->opr.ctx_type = WORD_DELIM;
}
break;
case 'B':
if (!(syntax & RE_NO_GNU_OPS))
{
token->type = ANCHOR;
token->opr.ctx_type = NOT_WORD_DELIM;
}
break;
case 'w':
if (!(syntax & RE_NO_GNU_OPS))
token->type = OP_WORD;
break;
case 'W':
if (!(syntax & RE_NO_GNU_OPS))
token->type = OP_NOTWORD;
break;
case 's':
if (!(syntax & RE_NO_GNU_OPS))
token->type = OP_SPACE;
break;
case 'S':
if (!(syntax & RE_NO_GNU_OPS))
token->type = OP_NOTSPACE;
break;
case '`':
if (!(syntax & RE_NO_GNU_OPS))
{
token->type = ANCHOR;
token->opr.ctx_type = BUF_FIRST;
}
break;
case '\'':
if (!(syntax & RE_NO_GNU_OPS))
{
token->type = ANCHOR;
token->opr.ctx_type = BUF_LAST;
}
break;
case '(':
if (!(syntax & RE_NO_BK_PARENS))
token->type = OP_OPEN_SUBEXP;
break;
case ')':
if (!(syntax & RE_NO_BK_PARENS))
token->type = OP_CLOSE_SUBEXP;
break;
case '+':
if (!(syntax & RE_LIMITED_OPS) && (syntax & RE_BK_PLUS_QM))
token->type = OP_DUP_PLUS;
break;
case '?':
if (!(syntax & RE_LIMITED_OPS) && (syntax & RE_BK_PLUS_QM))
token->type = OP_DUP_QUESTION;
break;
case '{':
if ((syntax & RE_INTERVALS) && (!(syntax & RE_NO_BK_BRACES)))
token->type = OP_OPEN_DUP_NUM;
break;
case '}':
if ((syntax & RE_INTERVALS) && (!(syntax & RE_NO_BK_BRACES)))
token->type = OP_CLOSE_DUP_NUM;
break;
default:
break;
}
return 2;
}
token->type = CHARACTER;
#ifdef RE_ENABLE_I18N
if (input->mb_cur_max > 1)
{
wint_t wc = re_string_wchar_at (input, re_string_cur_idx (input));
token->word_char = IS_WIDE_WORD_CHAR (wc) != 0;
}
else
#endif
token->word_char = IS_WORD_CHAR (token->opr.c);
switch (c)
{
case '\n':
if (syntax & RE_NEWLINE_ALT)
token->type = OP_ALT;
break;
case '|':
if (!(syntax & RE_LIMITED_OPS) && (syntax & RE_NO_BK_VBAR))
token->type = OP_ALT;
break;
case '*':
token->type = OP_DUP_ASTERISK;
break;
case '+':
if (!(syntax & RE_LIMITED_OPS) && !(syntax & RE_BK_PLUS_QM))
token->type = OP_DUP_PLUS;
break;
case '?':
if (!(syntax & RE_LIMITED_OPS) && !(syntax & RE_BK_PLUS_QM))
token->type = OP_DUP_QUESTION;
break;
case '{':
if ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
token->type = OP_OPEN_DUP_NUM;
break;
case '}':
if ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
token->type = OP_CLOSE_DUP_NUM;
break;
case '(':
if (syntax & RE_NO_BK_PARENS)
token->type = OP_OPEN_SUBEXP;
break;
case ')':
if (syntax & RE_NO_BK_PARENS)
token->type = OP_CLOSE_SUBEXP;
break;
case '[':
token->type = OP_OPEN_BRACKET;
break;
case '.':
token->type = OP_PERIOD;
break;
case '^':
if (!(syntax & (RE_CONTEXT_INDEP_ANCHORS | RE_CARET_ANCHORS_HERE)) &&
re_string_cur_idx (input) != 0)
{
char prev = re_string_peek_byte (input, -1);
if (!(syntax & RE_NEWLINE_ALT) || prev != '\n')
break;
}
token->type = ANCHOR;
token->opr.ctx_type = LINE_FIRST;
break;
case '$':
if (!(syntax & RE_CONTEXT_INDEP_ANCHORS) &&
re_string_cur_idx (input) + 1 != re_string_length (input))
{
re_token_t next;
re_string_skip_bytes (input, 1);
peek_token (&next, input, syntax);
re_string_skip_bytes (input, -1);
if (next.type != OP_ALT && next.type != OP_CLOSE_SUBEXP)
break;
}
token->type = ANCHOR;
token->opr.ctx_type = LINE_LAST;
break;
default:
break;
}
return 1;
}
/* Peek a token from INPUT, and return the length of the token.
We must not use this function out of bracket expressions. */
static int
internal_function
peek_token_bracket (re_token_t *token, re_string_t *input, reg_syntax_t syntax)
{
unsigned char c;
if (re_string_eoi (input))
{
token->type = END_OF_RE;
return 0;
}
c = re_string_peek_byte (input, 0);
token->opr.c = c;
#ifdef RE_ENABLE_I18N
if (input->mb_cur_max > 1 &&
!re_string_first_byte (input, re_string_cur_idx (input)))
{
token->type = CHARACTER;
return 1;
}
#endif /* RE_ENABLE_I18N */
if (c == '\\' && (syntax & RE_BACKSLASH_ESCAPE_IN_LISTS)
&& re_string_cur_idx (input) + 1 < re_string_length (input))
{
/* In this case, '\' escape a character. */
unsigned char c2;
re_string_skip_bytes (input, 1);
c2 = re_string_peek_byte (input, 0);
token->opr.c = c2;
token->type = CHARACTER;
return 1;
}
if (c == '[') /* '[' is a special char in a bracket exps. */
{
unsigned char c2;
int token_len;
if (re_string_cur_idx (input) + 1 < re_string_length (input))
c2 = re_string_peek_byte (input, 1);
else
c2 = 0;
token->opr.c = c2;
token_len = 2;
switch (c2)
{
case '.':
token->type = OP_OPEN_COLL_ELEM;
break;
case '=':
token->type = OP_OPEN_EQUIV_CLASS;
break;
case ':':
if (syntax & RE_CHAR_CLASSES)
{
token->type = OP_OPEN_CHAR_CLASS;
break;
}
/* else fall through. */
default:
token->type = CHARACTER;
token->opr.c = c;
token_len = 1;
break;
}
return token_len;
}
switch (c)
{
case '-':
token->type = OP_CHARSET_RANGE;
break;
case ']':
token->type = OP_CLOSE_BRACKET;
break;
case '^':
token->type = OP_NON_MATCH_LIST;
break;
default:
token->type = CHARACTER;
}
return 1;
}
/* Functions for parser. */
/* Entry point of the parser.
Parse the regular expression REGEXP and return the structure tree.
If an error has occurred, ERR is set by error code, and return NULL.
This function build the following tree, from regular expression <reg_exp>:
CAT
/ \
/ \
<reg_exp> EOR
CAT means concatenation.
EOR means end of regular expression. */
static bin_tree_t *
parse (re_string_t *regexp, regex_t *preg, reg_syntax_t syntax,
reg_errcode_t *err)
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
bin_tree_t *tree, *eor, *root;
re_token_t current_token;
dfa->syntax = syntax;
fetch_token (&current_token, regexp, syntax | RE_CARET_ANCHORS_HERE);
tree = parse_reg_exp (regexp, preg, &current_token, syntax, 0, err);
if (BE (*err != REG_NOERROR && tree == NULL, 0))
return NULL;
eor = create_tree (dfa, NULL, NULL, END_OF_RE);
if (tree != NULL)
root = create_tree (dfa, tree, eor, CONCAT);
else
root = eor;
if (BE (eor == NULL || root == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
return root;
}
/* This function build the following tree, from regular expression
<branch1>|<branch2>:
ALT
/ \
/ \
<branch1> <branch2>
ALT means alternative, which represents the operator `|'. */
static bin_tree_t *
parse_reg_exp (re_string_t *regexp, regex_t *preg, re_token_t *token,
reg_syntax_t syntax, int nest, reg_errcode_t *err)
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
bin_tree_t *tree, *branch = NULL;
tree = parse_branch (regexp, preg, token, syntax, nest, err);
if (BE (*err != REG_NOERROR && tree == NULL, 0))
return NULL;
while (token->type == OP_ALT)
{
fetch_token (token, regexp, syntax | RE_CARET_ANCHORS_HERE);
if (token->type != OP_ALT && token->type != END_OF_RE
&& (nest == 0 || token->type != OP_CLOSE_SUBEXP))
{
branch = parse_branch (regexp, preg, token, syntax, nest, err);
if (BE (*err != REG_NOERROR && branch == NULL, 0))
return NULL;
}
else
branch = NULL;
tree = create_tree (dfa, tree, branch, OP_ALT);
if (BE (tree == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
}
return tree;
}
/* This function build the following tree, from regular expression
<exp1><exp2>:
CAT
/ \
/ \
<exp1> <exp2>
CAT means concatenation. */
static bin_tree_t *
parse_branch (re_string_t *regexp, regex_t *preg, re_token_t *token,
reg_syntax_t syntax, int nest, reg_errcode_t *err)
{
bin_tree_t *tree, *exp;
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
tree = parse_expression (regexp, preg, token, syntax, nest, err);
if (BE (*err != REG_NOERROR && tree == NULL, 0))
return NULL;
while (token->type != OP_ALT && token->type != END_OF_RE
&& (nest == 0 || token->type != OP_CLOSE_SUBEXP))
{
exp = parse_expression (regexp, preg, token, syntax, nest, err);
if (BE (*err != REG_NOERROR && exp == NULL, 0))
{
return NULL;
}
if (tree != NULL && exp != NULL)
{
tree = create_tree (dfa, tree, exp, CONCAT);
if (tree == NULL)
{
*err = REG_ESPACE;
return NULL;
}
}
else if (tree == NULL)
tree = exp;
/* Otherwise exp == NULL, we don't need to create new tree. */
}
return tree;
}
/* This function build the following tree, from regular expression a*:
*
|
a
*/
static bin_tree_t *
parse_expression (re_string_t *regexp, regex_t *preg, re_token_t *token,
reg_syntax_t syntax, int nest, reg_errcode_t *err)
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
bin_tree_t *tree;
switch (token->type)
{
case CHARACTER:
tree = create_token_tree (dfa, NULL, NULL, token);
if (BE (tree == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
#ifdef RE_ENABLE_I18N
if (dfa->mb_cur_max > 1)
{
while (!re_string_eoi (regexp)
&& !re_string_first_byte (regexp, re_string_cur_idx (regexp)))
{
bin_tree_t *mbc_remain;
fetch_token (token, regexp, syntax);
mbc_remain = create_token_tree (dfa, NULL, NULL, token);
tree = create_tree (dfa, tree, mbc_remain, CONCAT);
if (BE (mbc_remain == NULL || tree == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
}
}
#endif
break;
case OP_OPEN_SUBEXP:
tree = parse_sub_exp (regexp, preg, token, syntax, nest + 1, err);
if (BE (*err != REG_NOERROR && tree == NULL, 0))
return NULL;
break;
case OP_OPEN_BRACKET:
tree = parse_bracket_exp (regexp, dfa, token, syntax, err);
if (BE (*err != REG_NOERROR && tree == NULL, 0))
return NULL;
break;
case OP_BACK_REF:
if (!BE (dfa->completed_bkref_map & (1 << token->opr.idx), 1))
{
*err = REG_ESUBREG;
return NULL;
}
dfa->used_bkref_map |= 1 << token->opr.idx;
tree = create_token_tree (dfa, NULL, NULL, token);
if (BE (tree == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
++dfa->nbackref;
dfa->has_mb_node = 1;
break;
case OP_OPEN_DUP_NUM:
if (syntax & RE_CONTEXT_INVALID_DUP)
{
*err = REG_BADRPT;
return NULL;
}
/* FALLTHROUGH */
case OP_DUP_ASTERISK:
case OP_DUP_PLUS:
case OP_DUP_QUESTION:
if (syntax & RE_CONTEXT_INVALID_OPS)
{
*err = REG_BADRPT;
return NULL;
}
else if (syntax & RE_CONTEXT_INDEP_OPS)
{
fetch_token (token, regexp, syntax);
return parse_expression (regexp, preg, token, syntax, nest, err);
}
/* else fall through */
case OP_CLOSE_SUBEXP:
if ((token->type == OP_CLOSE_SUBEXP) &&
!(syntax & RE_UNMATCHED_RIGHT_PAREN_ORD))
{
*err = REG_ERPAREN;
return NULL;
}
/* else fall through */
case OP_CLOSE_DUP_NUM:
/* We treat it as a normal character. */
/* Then we can these characters as normal characters. */
token->type = CHARACTER;
/* mb_partial and word_char bits should be initialized already
by peek_token. */
tree = create_token_tree (dfa, NULL, NULL, token);
if (BE (tree == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
break;
case ANCHOR:
if ((token->opr.ctx_type
& (WORD_DELIM | NOT_WORD_DELIM | WORD_FIRST | WORD_LAST))
&& dfa->word_ops_used == 0)
init_word_char (dfa);
if (token->opr.ctx_type == WORD_DELIM
|| token->opr.ctx_type == NOT_WORD_DELIM)
{
bin_tree_t *tree_first, *tree_last;
if (token->opr.ctx_type == WORD_DELIM)
{
token->opr.ctx_type = WORD_FIRST;
tree_first = create_token_tree (dfa, NULL, NULL, token);
token->opr.ctx_type = WORD_LAST;
}
else
{
token->opr.ctx_type = INSIDE_WORD;
tree_first = create_token_tree (dfa, NULL, NULL, token);
token->opr.ctx_type = INSIDE_NOTWORD;
}
tree_last = create_token_tree (dfa, NULL, NULL, token);
tree = create_tree (dfa, tree_first, tree_last, OP_ALT);
if (BE (tree_first == NULL || tree_last == NULL || tree == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
}
else
{
tree = create_token_tree (dfa, NULL, NULL, token);
if (BE (tree == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
}
/* We must return here, since ANCHORs can't be followed
by repetition operators.
eg. RE"^*" is invalid or "<ANCHOR(^)><CHAR(*)>",
it must not be "<ANCHOR(^)><REPEAT(*)>". */
fetch_token (token, regexp, syntax);
return tree;
case OP_PERIOD:
tree = create_token_tree (dfa, NULL, NULL, token);
if (BE (tree == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
if (dfa->mb_cur_max > 1)
dfa->has_mb_node = 1;
break;
case OP_WORD:
case OP_NOTWORD:
tree = build_charclass_op (dfa, regexp->trans,
"alnum",
"_",
token->type == OP_NOTWORD, err);
if (BE (*err != REG_NOERROR && tree == NULL, 0))
return NULL;
break;
case OP_SPACE:
case OP_NOTSPACE:
tree = build_charclass_op (dfa, regexp->trans,
"space",
"",
token->type == OP_NOTSPACE, err);
if (BE (*err != REG_NOERROR && tree == NULL, 0))
return NULL;
break;
case OP_ALT:
case END_OF_RE:
return NULL;
case BACK_SLASH:
*err = REG_EESCAPE;
return NULL;
default:
/* Must not happen? */
#ifdef DEBUG
assert (0);
#endif
return NULL;
}
fetch_token (token, regexp, syntax);
while (token->type == OP_DUP_ASTERISK || token->type == OP_DUP_PLUS
|| token->type == OP_DUP_QUESTION || token->type == OP_OPEN_DUP_NUM)
{
tree = parse_dup_op (tree, regexp, dfa, token, syntax, err);
if (BE (*err != REG_NOERROR && tree == NULL, 0))
return NULL;
/* In BRE consecutive duplications are not allowed. */
if ((syntax & RE_CONTEXT_INVALID_DUP)
&& (token->type == OP_DUP_ASTERISK
|| token->type == OP_OPEN_DUP_NUM))
{
*err = REG_BADRPT;
return NULL;
}
}
return tree;
}
/* This function build the following tree, from regular expression
(<reg_exp>):
SUBEXP
|
<reg_exp>
*/
static bin_tree_t *
parse_sub_exp (re_string_t *regexp, regex_t *preg, re_token_t *token,
reg_syntax_t syntax, int nest, reg_errcode_t *err)
{
re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
bin_tree_t *tree;
size_t cur_nsub;
cur_nsub = preg->re_nsub++;
fetch_token (token, regexp, syntax | RE_CARET_ANCHORS_HERE);
/* The subexpression may be a null string. */
if (token->type == OP_CLOSE_SUBEXP)
tree = NULL;
else
{
tree = parse_reg_exp (regexp, preg, token, syntax, nest, err);
if (BE (*err == REG_NOERROR && token->type != OP_CLOSE_SUBEXP, 0))
*err = REG_EPAREN;
if (BE (*err != REG_NOERROR, 0))
return NULL;
}
if (cur_nsub <= '9' - '1')
dfa->completed_bkref_map |= 1 << cur_nsub;
tree = create_tree (dfa, tree, NULL, SUBEXP);
if (BE (tree == NULL, 0))
{
*err = REG_ESPACE;
return NULL;
}
tree->token.opr.idx = cur_nsub;
return tree;
}
/* This function parse repetition operators like "*", "+", "{1,3}" etc. */
static bin_tree_t *
parse_dup_op (bin_tree_t *elem, re_string_t *regexp, re_dfa_t *dfa,
re_token_t *token, reg_syntax_t syntax, reg_errcode_t *err)
{
bin_tree_t *tree = NULL, *old_tree = NULL;
int i, start, end, start_idx = re_string_cur_idx (regexp);
#ifndef RE_TOKEN_INIT_BUG
re_token_t start_token = *token;
#else
re_token_t start_token;
memcpy ((void *) &start_token, (void *) token, sizeof start_token);
#endif
if (token->type == OP_OPEN_DUP_NUM)
{
end = 0;
start = fetch_number (regexp, token, syntax);
if (start == -1)
{
if (token->type == CHARACTER && token->opr.c == ',')
start = 0; /* We treat "{,m}" as "{0,m}". */
else
{
*err = REG_BADBR; /* <re>{} is invalid. */
return NULL;
}
}
if (BE (start != -2, 1))
{
/* We treat "{n}" as "{n,n}". */
end = ((token->type == OP_CLOSE_DUP_NUM) ? start
: ((token->type == CHARACTER && token->opr.c == ',')
? fetch_number (regexp, token, syntax) : -2));
}
if (BE (start == -2 || end == -2, 0))
{
/* Invalid sequence. */
if (BE (!(syntax & RE_INVALID_INTERVAL_ORD), 0))
{
if (token->type == END_OF_RE)
*err = REG_EBRACE;
else
*err = REG_BADBR;
return NULL;
}
/* If the syntax bit is set, rollback. */
re_string_set_index (regexp, start_idx);
*token = start_token;
token->type = CHARACTER;
/* mb_partial and word_char bits should be already initialized by
peek_token. */
return elem;
}
if (BE ((end != -1 && start > end) || token->type != OP_CLOSE_DUP_NUM, 0))
{
/* First number greater than second. */
*err = REG_BADBR;
return NULL;
}
}
else
{
start = (token->type == OP_DUP_PLUS) ? 1 : 0;
end = (token->type == OP_DUP_QUESTION) ? 1 : -1;
}
fetch_token (token, regexp, syntax);
if (BE (elem == NULL, 0))
return NULL;
if (BE (start == 0 && end == 0, 0))
{
postorder (elem, free_tree, NULL);
return NULL;
}
/* Extract "<re>{n,m}" to "<re><re>...<re><re>{0,<m-n>}". */
if (BE (start > 0, 0))
{
tree = elem;
for (i = 2; i <= start; ++i)
{
elem = duplicate_tree (elem, dfa);
tree = create_tree (dfa, tree, elem, CONCAT);
if (BE (elem == NULL || tree == NULL, 0))
goto parse_dup_op_espace;
}
if (start == end)
return tree;
/* Duplicate ELEM before it is marked optional. */
elem = duplicate_tree (elem, dfa);
old_tree = tree;
}
else
old_tree = NULL;
if (elem->token.type == SUBEXP)
postorder (elem, mark_opt_subexp, (void *) (intptr_t) elem->token.opr.idx);
tree = create_tree (dfa, elem, NULL, (end == -1 ? OP_DUP_ASTERISK : OP_ALT));
if (BE (tree == NULL, 0))
goto parse_dup_op_espace;
/* This loop is actually executed only when end != -1,
to rewrite <re>{0,n} as (<re>(<re>...<re>?)?)?... We have
already created the start+1-th copy. */
for (i = start + 2; i <= end; ++i)
{
elem = duplicate_tree (elem, dfa);
tree = create_tree (dfa, tree, elem, CONCAT);
if (BE (elem == NULL || tree == NULL, 0))
goto parse_dup_op_espace;
tree = create_tree (dfa, tree, NULL, OP_ALT);
if (BE (tree == NULL, 0))
goto parse_dup_op_espace;
}
if (old_tree)
tree = create_tree (dfa, old_tree, tree, CONCAT);
return tree;
parse_dup_op_espace:
*err = REG_ESPACE;
return NULL;
}
/* Size of the names for collating symbol/equivalence_class/character_class.
I'm not sure, but maybe enough. */
#define BRACKET_NAME_BUF_SIZE 32
#ifndef _LIBC
/* Local function for parse_bracket_exp only used in case of NOT _LIBC.
Build the range expression which starts from START_ELEM, and ends
at END_ELEM. The result are written to MBCSET and SBCSET.
RANGE_ALLOC is the allocated size of mbcset->range_starts, and
mbcset->range_ends, is a pointer argument since we may
update it. */
static reg_errcode_t
internal_function
# ifdef RE_ENABLE_I18N
build_range_exp (bitset_t sbcset, re_charset_t *mbcset, int *range_alloc,
bracket_elem_t *start_elem, bracket_elem_t *end_elem)
# else /* not RE_ENABLE_I18N */
build_range_exp (bitset_t sbcset, bracket_elem_t *start_elem,
bracket_elem_t *end_elem)
# endif /* not RE_ENABLE_I18N */
{
unsigned int start_ch, end_ch;
/* Equivalence Classes and Character Classes can't be a range start/end. */