/* Definitions for data structures and routines for the regular
Copyright (C) 1985, 1989-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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
<https://www.gnu.org/licenses/>. */
/* Allow the use in C++ code. */
/* Define __USE_GNU to declare GNU extensions that violate the
POSIX name space rules. */
#ifdef _REGEX_LARGE_OFFSETS
/* Use types and values that are wide enough to represent signed and
unsigned byte offsets in memory. This currently works only when
the regex code is used outside of the GNU C library; it is not yet
supported within glibc itself, and glibc users should not define
/* The type of object sizes. */
typedef size_t __re_size_t;
/* The type of object sizes, in places where the traditional code
uses unsigned long int. */
typedef size_t __re_long_size_t;
/* The traditional GNU regex implementation mishandles strings longer
typedef unsigned int __re_size_t;
typedef unsigned long int __re_long_size_t;
/* The following two types have to be signed and unsigned integer type
wide enough to hold a value of a pointer. For most ANSI compilers
ptrdiff_t and size_t should be likely OK. Still size of these two
types is 2 for Microsoft C. Ugh... */
typedef long int s_reg_t;
typedef unsigned long int active_reg_t;
/* The following bits are used to determine the regexp syntax we
recognize. The set/not-set meanings are chosen so that Emacs syntax
remains the value 0. The bits are given in alphabetical order, and
the definitions shifted by one from the previous bit; thus, when we
add or remove a bit, only one other definition need change. */
typedef unsigned long int reg_syntax_t;
/* If this bit is not set, then \ inside a bracket expression is literal.
If set, then such a \ quotes the following character. */
# define RE_BACKSLASH_ESCAPE_IN_LISTS ((unsigned long int) 1)
/* If this bit is not set, then + and ? are operators, and \+ and \? are
If set, then \+ and \? are operators and + and ? are literals. */
# define RE_BK_PLUS_QM (RE_BACKSLASH_ESCAPE_IN_LISTS << 1)
/* If this bit is set, then character classes are supported. They are:
[:alpha:], [:upper:], [:lower:], [:digit:], [:alnum:], [:xdigit:],
[:space:], [:print:], [:punct:], [:graph:], and [:cntrl:].
If not set, then character classes are not supported. */
# define RE_CHAR_CLASSES (RE_BK_PLUS_QM << 1)
/* If this bit is set, then ^ and $ are always anchors (outside bracket
If this bit is not set, then it depends:
^ is an anchor if it is at the beginning of a regular
expression or after an open-group or an alternation operator;
$ is an anchor if it is at the end of a regular expression, or
before a close-group or an alternation operator.
This bit could be (re)combined with RE_CONTEXT_INDEP_OPS, because
POSIX draft 11.2 says that * etc. in leading positions is undefined.
We already implemented a previous draft which made those constructs
invalid, though, so we haven't changed the code back. */
# define RE_CONTEXT_INDEP_ANCHORS (RE_CHAR_CLASSES << 1)
/* If this bit is set, then special characters are always special
regardless of where they are in the pattern.
If this bit is not set, then special characters are special only in
some contexts; otherwise they are ordinary. Specifically,
* + ? and intervals are only special when not after the beginning,
open-group, or alternation operator. */
# define RE_CONTEXT_INDEP_OPS (RE_CONTEXT_INDEP_ANCHORS << 1)
/* If this bit is set, then *, +, ?, and { cannot be first in an re or
immediately after an alternation or begin-group operator. */
# define RE_CONTEXT_INVALID_OPS (RE_CONTEXT_INDEP_OPS << 1)
/* If this bit is set, then . matches newline.
If not set, then it doesn't. */
# define RE_DOT_NEWLINE (RE_CONTEXT_INVALID_OPS << 1)
/* If this bit is set, then . doesn't match NUL.
If not set, then it does. */
# define RE_DOT_NOT_NULL (RE_DOT_NEWLINE << 1)
/* If this bit is set, nonmatching lists [^...] do not match newline.
# define RE_HAT_LISTS_NOT_NEWLINE (RE_DOT_NOT_NULL << 1)
/* If this bit is set, either \{...\} or {...} defines an
interval, depending on RE_NO_BK_BRACES.
If not set, \{, \}, {, and } are literals. */
# define RE_INTERVALS (RE_HAT_LISTS_NOT_NEWLINE << 1)
/* If this bit is set, +, ? and | aren't recognized as operators.
# define RE_LIMITED_OPS (RE_INTERVALS << 1)
/* If this bit is set, newline is an alternation operator.
If not set, newline is literal. */
# define RE_NEWLINE_ALT (RE_LIMITED_OPS << 1)
/* If this bit is set, then '{...}' defines an interval, and \{ and \}
If not set, then '\{...\}' defines an interval. */
# define RE_NO_BK_BRACES (RE_NEWLINE_ALT << 1)
/* If this bit is set, (...) defines a group, and \( and \) are literals.
If not set, \(...\) defines a group, and ( and ) are literals. */
# define RE_NO_BK_PARENS (RE_NO_BK_BRACES << 1)
/* If this bit is set, then \<digit> matches <digit>.
If not set, then \<digit> is a back-reference. */
# define RE_NO_BK_REFS (RE_NO_BK_PARENS << 1)
/* If this bit is set, then | is an alternation operator, and \| is literal.
If not set, then \| is an alternation operator, and | is literal. */
# define RE_NO_BK_VBAR (RE_NO_BK_REFS << 1)
/* If this bit is set, then an ending range point collating higher
than the starting range point, as in [z-a], is invalid.
If not set, then when ending range point collates higher than the
starting range point, the range is ignored. */
# define RE_NO_EMPTY_RANGES (RE_NO_BK_VBAR << 1)
/* If this bit is set, then an unmatched ) is ordinary.
If not set, then an unmatched ) is invalid. */
# define RE_UNMATCHED_RIGHT_PAREN_ORD (RE_NO_EMPTY_RANGES << 1)
/* If this bit is set, succeed as soon as we match the whole pattern,
without further backtracking. */
# define RE_NO_POSIX_BACKTRACKING (RE_UNMATCHED_RIGHT_PAREN_ORD << 1)
/* If this bit is set, do not process the GNU regex operators.
If not set, then the GNU regex operators are recognized. */
# define RE_NO_GNU_OPS (RE_NO_POSIX_BACKTRACKING << 1)
/* If this bit is set, turn on internal regex debugging.
If not set, and debugging was on, turn it off.
This only works if regex.c is compiled -DDEBUG.
We define this bit always, so that all that's needed to turn on
debugging is to recompile regex.c; the calling code can always have
this bit set, and it won't affect anything in the normal case. */
# define RE_DEBUG (RE_NO_GNU_OPS << 1)
/* If this bit is set, a syntactically invalid interval is treated as
a string of ordinary characters. For example, the ERE 'a{1' is
# define RE_INVALID_INTERVAL_ORD (RE_DEBUG << 1)
/* If this bit is set, then ignore case when matching.
If not set, then case is significant. */
# define RE_ICASE (RE_INVALID_INTERVAL_ORD << 1)
/* This bit is used internally like RE_CONTEXT_INDEP_ANCHORS but only
for ^, because it is difficult to scan the regex backwards to find
whether ^ should be special. */
# define RE_CARET_ANCHORS_HERE (RE_ICASE << 1)
/* If this bit is set, then \{ cannot be first in a regex or
immediately after an alternation, open-group or \} operator. */
# define RE_CONTEXT_INVALID_DUP (RE_CARET_ANCHORS_HERE << 1)
/* If this bit is set, then no_sub will be set to 1 during
# define RE_NO_SUB (RE_CONTEXT_INVALID_DUP << 1)
/* This global variable defines the particular regexp syntax to use (for
some interfaces). When a regexp is compiled, the syntax used is
stored in the pattern buffer, so changing this does not affect
already-compiled regexps. */
extern reg_syntax_t re_syntax_options;
/* Define combinations of the above bits for the standard possibilities.
(The [[[ comments delimit what gets put into the Texinfo file, so
/* [[[begin syntaxes]]] */
# define RE_SYNTAX_EMACS 0
(RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DOT_NOT_NULL \
| RE_NO_BK_PARENS | RE_NO_BK_REFS \
| RE_NO_BK_VBAR | RE_NO_EMPTY_RANGES \
| RE_DOT_NEWLINE | RE_CONTEXT_INDEP_ANCHORS \
| RE_UNMATCHED_RIGHT_PAREN_ORD | RE_NO_GNU_OPS)
# define RE_SYNTAX_GNU_AWK \
((RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS \
| RE_INVALID_INTERVAL_ORD) \
& ~(RE_DOT_NOT_NULL | RE_CONTEXT_INDEP_OPS \
| RE_CONTEXT_INVALID_OPS ))
# define RE_SYNTAX_POSIX_AWK \
(RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS \
| RE_INTERVALS | RE_NO_GNU_OPS \
| RE_INVALID_INTERVAL_ORD)
# define RE_SYNTAX_GREP \
((RE_SYNTAX_POSIX_BASIC | RE_NEWLINE_ALT) \
& ~(RE_CONTEXT_INVALID_DUP | RE_DOT_NOT_NULL))
# define RE_SYNTAX_EGREP \
((RE_SYNTAX_POSIX_EXTENDED | RE_INVALID_INTERVAL_ORD | RE_NEWLINE_ALT) \
& ~(RE_CONTEXT_INVALID_OPS | RE_DOT_NOT_NULL))
/* POSIX grep -E behavior is no longer incompatible with GNU. */
# define RE_SYNTAX_POSIX_EGREP \
/* P1003.2/D11.2, section 4.20.7.1, lines 5078ff. */
# define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC
# define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC
/* Syntax bits common to both basic and extended POSIX regex syntax. */
# define _RE_SYNTAX_POSIX_COMMON \
(RE_CHAR_CLASSES | RE_DOT_NEWLINE | RE_DOT_NOT_NULL \
| RE_INTERVALS | RE_NO_EMPTY_RANGES)
# define RE_SYNTAX_POSIX_BASIC \
(_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM | RE_CONTEXT_INVALID_DUP)
/* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes
RE_LIMITED_OPS, i.e., \? \+ \| are not recognized. Actually, this
isn't minimal, since other operators, such as \`, aren't disabled. */
# define RE_SYNTAX_POSIX_MINIMAL_BASIC \
(_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS)
# define RE_SYNTAX_POSIX_EXTENDED \
(_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \
| RE_CONTEXT_INDEP_OPS | RE_NO_BK_BRACES \
| RE_NO_BK_PARENS | RE_NO_BK_VBAR \
| RE_CONTEXT_INVALID_OPS | RE_UNMATCHED_RIGHT_PAREN_ORD)
/* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INDEP_OPS is
removed and RE_NO_BK_REFS is added. */
# define RE_SYNTAX_POSIX_MINIMAL_EXTENDED \
(_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS \
| RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES \
| RE_NO_BK_PARENS | RE_NO_BK_REFS \
| RE_NO_BK_VBAR | RE_UNMATCHED_RIGHT_PAREN_ORD)
/* Maximum number of duplicates an interval can allow. POSIX-conforming
systems might define this in <limits.h>, but we want our
value, so remove any previous define. */
# ifdef _REGEX_INCLUDE_LIMITS_H
/* RE_DUP_MAX is 2**15 - 1 because an earlier implementation stored
the counter as a 2-byte signed integer. This is no longer true, so
RE_DUP_MAX could be increased to (INT_MAX / 10 - 1), or to
((SIZE_MAX - 9) / 10) if _REGEX_LARGE_OFFSETS is defined.
However, there would be a huge performance problem if someone
actually used a pattern like a\{214748363\}, so RE_DUP_MAX retains
# define RE_DUP_MAX (0x7fff)
/* POSIX 'cflags' bits (i.e., information for 'regcomp'). */
/* If this bit is set, then use extended regular expression syntax.
If not set, then use basic regular expression syntax. */
/* If this bit is set, then ignore case when matching.
If not set, then case is significant. */
#define REG_ICASE (1 << 1)
/* If this bit is set, then anchors do not match at newline
characters in the string.
If not set, then anchors do match at newlines. */
#define REG_NEWLINE (1 << 2)
/* If this bit is set, then report only success or fail in regexec.
If not set, then returns differ between not matching and errors. */
#define REG_NOSUB (1 << 3)
/* POSIX 'eflags' bits (i.e., information for regexec). */
/* If this bit is set, then the beginning-of-line operator doesn't match
the beginning of the string (presumably because it's not the
If not set, then the beginning-of-line operator does match the
beginning of the string. */
/* Like REG_NOTBOL, except for the end-of-line. */
#define REG_NOTEOL (1 << 1)
/* Use PMATCH[0] to delimit the start and end of the search in the
#define REG_STARTEND (1 << 2)
/* If any error codes are removed, changed, or added, update the
'__re_error_msgid' table in regcomp.c. */
_REG_ENOSYS = -1, /* This will never happen for this implementation. */
_REG_NOERROR = 0, /* Success. */
_REG_NOMATCH, /* Didn't find a match (for regexec). */
/* POSIX regcomp return error codes. (In the order listed in the
_REG_BADPAT, /* Invalid pattern. */
_REG_ECOLLATE, /* Invalid collating element. */
_REG_ECTYPE, /* Invalid character class name. */
_REG_EESCAPE, /* Trailing backslash. */
_REG_ESUBREG, /* Invalid back reference. */
_REG_EBRACK, /* Unmatched left bracket. */
_REG_EPAREN, /* Parenthesis imbalance. */
_REG_EBRACE, /* Unmatched \{. */
_REG_BADBR, /* Invalid contents of \{\}. */
_REG_ERANGE, /* Invalid range end. */
_REG_ESPACE, /* Ran out of memory. */
_REG_BADRPT, /* No preceding re for repetition op. */
/* Error codes we've added. */
_REG_EEND, /* Premature end. */
_REG_ESIZE, /* Too large (e.g., repeat count too large). */
_REG_ERPAREN /* Unmatched ) or \); not returned from regcomp. */
#if defined _XOPEN_SOURCE || defined __USE_XOPEN2K
# define REG_ENOSYS _REG_ENOSYS
#define REG_NOERROR _REG_NOERROR
#define REG_NOMATCH _REG_NOMATCH
#define REG_BADPAT _REG_BADPAT
#define REG_ECOLLATE _REG_ECOLLATE
#define REG_ECTYPE _REG_ECTYPE
#define REG_EESCAPE _REG_EESCAPE
#define REG_ESUBREG _REG_ESUBREG
#define REG_EBRACK _REG_EBRACK
#define REG_EPAREN _REG_EPAREN
#define REG_EBRACE _REG_EBRACE
#define REG_BADBR _REG_BADBR
#define REG_ERANGE _REG_ERANGE
#define REG_ESPACE _REG_ESPACE
#define REG_BADRPT _REG_BADRPT
#define REG_EEND _REG_EEND
#define REG_ESIZE _REG_ESIZE
#define REG_ERPAREN _REG_ERPAREN
/* This data structure represents a compiled pattern. Before calling
the pattern compiler, the fields 'buffer', 'allocated', 'fastmap',
and 'translate' can be set. After the pattern has been compiled,
the fields 're_nsub', 'not_bol' and 'not_eol' are available. All
other fields are private to the regex routines. */
#ifndef RE_TRANSLATE_TYPE
# define __RE_TRANSLATE_TYPE unsigned char *
# define RE_TRANSLATE_TYPE __RE_TRANSLATE_TYPE
# define __REPB_PREFIX(name) name
# define __REPB_PREFIX(name) __##name
/* Space that holds the compiled pattern. The type
'struct re_dfa_t' is private and is not declared here. */
struct re_dfa_t *__REPB_PREFIX(buffer);
/* Number of bytes to which 'buffer' points. */
__re_long_size_t __REPB_PREFIX(allocated);
/* Number of bytes actually used in 'buffer'. */
__re_long_size_t __REPB_PREFIX(used);
/* Syntax setting with which the pattern was compiled. */
reg_syntax_t __REPB_PREFIX(syntax);
/* Pointer to a fastmap, if any, otherwise zero. re_search uses the
fastmap, if there is one, to skip over impossible starting points
char *__REPB_PREFIX(fastmap);
/* Either a translate table to apply to all characters before
comparing them, or zero for no translation. The translation is
applied to a pattern when it is compiled and to a string when it
__RE_TRANSLATE_TYPE __REPB_PREFIX(translate);
/* Number of subexpressions found by the compiler. */
/* Zero if this pattern cannot match the empty string, one else.
Well, in truth it's used only in 're_search_2', to see whether or
not we should use the fastmap, so we don't set this absolutely
perfectly; see 're_compile_fastmap' (the "duplicate" case). */
unsigned __REPB_PREFIX(can_be_null) : 1;
/* If REGS_UNALLOCATED, allocate space in the 'regs' structure
for 'max (RE_NREGS, re_nsub + 1)' groups.
If REGS_REALLOCATE, reallocate space if necessary.
If REGS_FIXED, use what's there. */
# define REGS_UNALLOCATED 0
# define REGS_REALLOCATE 1
unsigned __REPB_PREFIX(regs_allocated) : 2;
/* Set to zero when 're_compile_pattern' compiles a pattern; set to
one by 're_compile_fastmap' if it updates the fastmap. */
unsigned __REPB_PREFIX(fastmap_accurate) : 1;
/* If set, 're_match_2' does not return information about
unsigned __REPB_PREFIX(no_sub) : 1;
/* If set, a beginning-of-line anchor doesn't match at the beginning
unsigned __REPB_PREFIX(not_bol) : 1;
/* Similarly for an end-of-line anchor. */
unsigned __REPB_PREFIX(not_eol) : 1;
/* If true, an anchor at a newline matches. */
unsigned __REPB_PREFIX(newline_anchor) : 1;
typedef struct re_pattern_buffer regex_t;
/* Type for byte offsets within the string. POSIX mandates this. */
#ifdef _REGEX_LARGE_OFFSETS
/* POSIX 1003.1-2008 requires that regoff_t be at least as wide as
ptrdiff_t and ssize_t. We don't know of any hosts where ptrdiff_t
is wider than ssize_t, so ssize_t is safe. ptrdiff_t is not
visible here, so use ssize_t. */
typedef ssize_t regoff_t;
/* The traditional GNU regex implementation mishandles strings longer
/* This is the structure we store register match data in. See
regex.texinfo for a full description of what registers match. */