382 lines
15 KiB
C
382 lines
15 KiB
C
|
/*************************************************
|
||
|
* Perl-Compatible Regular Expressions *
|
||
|
*************************************************/
|
||
|
|
||
|
|
||
|
/* This is a library of functions to support regular expressions whose syntax
|
||
|
and semantics are as close as possible to those of the Perl 5 language. See
|
||
|
the file Tech.Notes for some information on the internals.
|
||
|
|
||
|
Written by: Philip Hazel <ph10@cam.ac.uk>
|
||
|
|
||
|
Copyright (c) 1997-2000 University of Cambridge
|
||
|
|
||
|
-----------------------------------------------------------------------------
|
||
|
Permission is granted to anyone to use this software for any purpose on any
|
||
|
computer system, and to redistribute it freely, subject to the following
|
||
|
restrictions:
|
||
|
|
||
|
1. This software 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.
|
||
|
|
||
|
2. The origin of this software must not be misrepresented, either by
|
||
|
explicit claim or by omission.
|
||
|
|
||
|
3. Altered versions must be plainly marked as such, and must not be
|
||
|
misrepresented as being the original software.
|
||
|
|
||
|
4. If PCRE is embedded in any software that is released under the GNU
|
||
|
General Purpose Licence (GPL), then the terms of that licence shall
|
||
|
supersede any condition above with which it is incompatible.
|
||
|
-----------------------------------------------------------------------------
|
||
|
*/
|
||
|
|
||
|
/* This header contains definitions that are shared between the different
|
||
|
modules, but which are not relevant to the outside. */
|
||
|
|
||
|
/* Get the definitions provided by running "configure" */
|
||
|
|
||
|
#include "config.h"
|
||
|
|
||
|
/* To cope with SunOS4 and other systems that lack memmove() but have bcopy(),
|
||
|
define a macro for memmove() if HAVE_MEMMOVE is false, provided that HAVE_BCOPY
|
||
|
is set. Otherwise, include an emulating function for those systems that have
|
||
|
neither (there some non-Unix environments where this is the case). This assumes
|
||
|
that all calls to memmove are moving strings upwards in store, which is the
|
||
|
case in PCRE. */
|
||
|
|
||
|
#if ! HAVE_MEMMOVE
|
||
|
#undef memmove /* some systems may have a macro */
|
||
|
#if HAVE_BCOPY
|
||
|
#define memmove(a, b, c) bcopy(b, a, c)
|
||
|
#else
|
||
|
void *
|
||
|
pcre_memmove(unsigned char *dest, const unsigned char *src, size_t n)
|
||
|
{
|
||
|
int i;
|
||
|
dest += n;
|
||
|
src += n;
|
||
|
for (i = 0; i < n; ++i) *(--dest) = *(--src);
|
||
|
}
|
||
|
#define memmove(a, b, c) pcre_memmove(a, b, c)
|
||
|
#endif
|
||
|
#endif
|
||
|
|
||
|
/* Standard C headers plus the external interface definition */
|
||
|
|
||
|
#include <ctype.h>
|
||
|
#include <limits.h>
|
||
|
#include <stddef.h>
|
||
|
#include <stdio.h>
|
||
|
#include <stdlib.h>
|
||
|
#include <string.h>
|
||
|
#include "pcre.h"
|
||
|
|
||
|
/* In case there is no definition of offsetof() provided - though any proper
|
||
|
Standard C system should have one. */
|
||
|
|
||
|
#ifndef offsetof
|
||
|
#define offsetof(p_type,field) ((size_t)&(((p_type *)0)->field))
|
||
|
#endif
|
||
|
|
||
|
/* These are the public options that can change during matching. */
|
||
|
|
||
|
#define PCRE_IMS (PCRE_CASELESS|PCRE_MULTILINE|PCRE_DOTALL)
|
||
|
|
||
|
/* Private options flags start at the most significant end of the four bytes,
|
||
|
but skip the top bit so we can use ints for convenience without getting tangled
|
||
|
with negative values. The public options defined in pcre.h start at the least
|
||
|
significant end. Make sure they don't overlap, though now that we have expanded
|
||
|
to four bytes there is plenty of space. */
|
||
|
|
||
|
#define PCRE_FIRSTSET 0x40000000 /* first_char is set */
|
||
|
#define PCRE_REQCHSET 0x20000000 /* req_char is set */
|
||
|
#define PCRE_STARTLINE 0x10000000 /* start after \n for multiline */
|
||
|
#define PCRE_INGROUP 0x08000000 /* compiling inside a group */
|
||
|
#define PCRE_ICHANGED 0x04000000 /* i option changes within regex */
|
||
|
|
||
|
/* Options for the "extra" block produced by pcre_study(). */
|
||
|
|
||
|
#define PCRE_STUDY_MAPPED 0x01 /* a map of starting chars exists */
|
||
|
|
||
|
/* Masks for identifying the public options which are permitted at compile
|
||
|
time, run time or study time, respectively. */
|
||
|
|
||
|
#define PUBLIC_OPTIONS \
|
||
|
(PCRE_CASELESS|PCRE_EXTENDED|PCRE_ANCHORED|PCRE_MULTILINE| \
|
||
|
PCRE_DOTALL|PCRE_DOLLAR_ENDONLY|PCRE_EXTRA|PCRE_UNGREEDY|PCRE_UTF8)
|
||
|
|
||
|
#define PUBLIC_EXEC_OPTIONS \
|
||
|
(PCRE_ANCHORED|PCRE_NOTBOL|PCRE_NOTEOL|PCRE_NOTEMPTY)
|
||
|
|
||
|
#define PUBLIC_STUDY_OPTIONS 0 /* None defined */
|
||
|
|
||
|
/* Magic number to provide a small check against being handed junk. */
|
||
|
|
||
|
#define MAGIC_NUMBER 0x50435245UL /* 'PCRE' */
|
||
|
|
||
|
/* Miscellaneous definitions */
|
||
|
|
||
|
typedef int BOOL;
|
||
|
|
||
|
#define FALSE 0
|
||
|
#define TRUE 1
|
||
|
|
||
|
/* These are escaped items that aren't just an encoding of a particular data
|
||
|
value such as \n. They must have non-zero values, as check_escape() returns
|
||
|
their negation. Also, they must appear in the same order as in the opcode
|
||
|
definitions below, up to ESC_z. The final one must be ESC_REF as subsequent
|
||
|
values are used for \1, \2, \3, etc. There is a test in the code for an escape
|
||
|
greater than ESC_b and less than ESC_X to detect the types that may be
|
||
|
repeated. If any new escapes are put in-between that don't consume a character,
|
||
|
that code will have to change. */
|
||
|
|
||
|
enum { ESC_A = 1, ESC_B, ESC_b, ESC_D, ESC_d, ESC_S, ESC_s, ESC_W, ESC_w,
|
||
|
ESC_Z, ESC_z, ESC_REF };
|
||
|
|
||
|
/* Opcode table: OP_BRA must be last, as all values >= it are used for brackets
|
||
|
that extract substrings. Starting from 1 (i.e. after OP_END), the values up to
|
||
|
OP_EOD must correspond in order to the list of escapes immediately above. */
|
||
|
|
||
|
enum {
|
||
|
OP_END, /* End of pattern */
|
||
|
|
||
|
/* Values corresponding to backslashed metacharacters */
|
||
|
|
||
|
OP_SOD, /* Start of data: \A */
|
||
|
OP_NOT_WORD_BOUNDARY, /* \B */
|
||
|
OP_WORD_BOUNDARY, /* \b */
|
||
|
OP_NOT_DIGIT, /* \D */
|
||
|
OP_DIGIT, /* \d */
|
||
|
OP_NOT_WHITESPACE, /* \S */
|
||
|
OP_WHITESPACE, /* \s */
|
||
|
OP_NOT_WORDCHAR, /* \W */
|
||
|
OP_WORDCHAR, /* \w */
|
||
|
OP_EODN, /* End of data or \n at end of data: \Z. */
|
||
|
OP_EOD, /* End of data: \z */
|
||
|
|
||
|
OP_OPT, /* Set runtime options */
|
||
|
OP_CIRC, /* Start of line - varies with multiline switch */
|
||
|
OP_DOLL, /* End of line - varies with multiline switch */
|
||
|
OP_ANY, /* Match any character */
|
||
|
OP_CHARS, /* Match string of characters */
|
||
|
OP_NOT, /* Match anything but the following char */
|
||
|
|
||
|
OP_STAR, /* The maximizing and minimizing versions of */
|
||
|
OP_MINSTAR, /* all these opcodes must come in pairs, with */
|
||
|
OP_PLUS, /* the minimizing one second. */
|
||
|
OP_MINPLUS, /* This first set applies to single characters */
|
||
|
OP_QUERY,
|
||
|
OP_MINQUERY,
|
||
|
OP_UPTO, /* From 0 to n matches */
|
||
|
OP_MINUPTO,
|
||
|
OP_EXACT, /* Exactly n matches */
|
||
|
|
||
|
OP_NOTSTAR, /* The maximizing and minimizing versions of */
|
||
|
OP_NOTMINSTAR, /* all these opcodes must come in pairs, with */
|
||
|
OP_NOTPLUS, /* the minimizing one second. */
|
||
|
OP_NOTMINPLUS, /* This first set applies to "not" single characters */
|
||
|
OP_NOTQUERY,
|
||
|
OP_NOTMINQUERY,
|
||
|
OP_NOTUPTO, /* From 0 to n matches */
|
||
|
OP_NOTMINUPTO,
|
||
|
OP_NOTEXACT, /* Exactly n matches */
|
||
|
|
||
|
OP_TYPESTAR, /* The maximizing and minimizing versions of */
|
||
|
OP_TYPEMINSTAR, /* all these opcodes must come in pairs, with */
|
||
|
OP_TYPEPLUS, /* the minimizing one second. These codes must */
|
||
|
OP_TYPEMINPLUS, /* be in exactly the same order as those above. */
|
||
|
OP_TYPEQUERY, /* This set applies to character types such as \d */
|
||
|
OP_TYPEMINQUERY,
|
||
|
OP_TYPEUPTO, /* From 0 to n matches */
|
||
|
OP_TYPEMINUPTO,
|
||
|
OP_TYPEEXACT, /* Exactly n matches */
|
||
|
|
||
|
OP_CRSTAR, /* The maximizing and minimizing versions of */
|
||
|
OP_CRMINSTAR, /* all these opcodes must come in pairs, with */
|
||
|
OP_CRPLUS, /* the minimizing one second. These codes must */
|
||
|
OP_CRMINPLUS, /* be in exactly the same order as those above. */
|
||
|
OP_CRQUERY, /* These are for character classes and back refs */
|
||
|
OP_CRMINQUERY,
|
||
|
OP_CRRANGE, /* These are different to the three seta above. */
|
||
|
OP_CRMINRANGE,
|
||
|
|
||
|
OP_CLASS, /* Match a character class */
|
||
|
OP_REF, /* Match a back reference */
|
||
|
OP_RECURSE, /* Match this pattern recursively */
|
||
|
|
||
|
OP_ALT, /* Start of alternation */
|
||
|
OP_KET, /* End of group that doesn't have an unbounded repeat */
|
||
|
OP_KETRMAX, /* These two must remain together and in this */
|
||
|
OP_KETRMIN, /* order. They are for groups the repeat for ever. */
|
||
|
|
||
|
/* The assertions must come before ONCE and COND */
|
||
|
|
||
|
OP_ASSERT, /* Positive lookahead */
|
||
|
OP_ASSERT_NOT, /* Negative lookahead */
|
||
|
OP_ASSERTBACK, /* Positive lookbehind */
|
||
|
OP_ASSERTBACK_NOT, /* Negative lookbehind */
|
||
|
OP_REVERSE, /* Move pointer back - used in lookbehind assertions */
|
||
|
|
||
|
/* ONCE and COND must come after the assertions, with ONCE first, as there's
|
||
|
a test for >= ONCE for a subpattern that isn't an assertion. */
|
||
|
|
||
|
OP_ONCE, /* Once matched, don't back up into the subpattern */
|
||
|
OP_COND, /* Conditional group */
|
||
|
OP_CREF, /* Used to hold an extraction string number */
|
||
|
|
||
|
OP_BRAZERO, /* These two must remain together and in this */
|
||
|
OP_BRAMINZERO, /* order. */
|
||
|
|
||
|
OP_BRA /* This and greater values are used for brackets that
|
||
|
extract substrings. */
|
||
|
};
|
||
|
|
||
|
/* The highest extraction number. This is limited by the number of opcodes
|
||
|
left after OP_BRA, i.e. 255 - OP_BRA. We actually set it somewhat lower. */
|
||
|
|
||
|
#define EXTRACT_MAX 99
|
||
|
|
||
|
/* The texts of compile-time error messages are defined as macros here so that
|
||
|
they can be accessed by the POSIX wrapper and converted into error codes. Yes,
|
||
|
I could have used error codes in the first place, but didn't feel like changing
|
||
|
just to accommodate the POSIX wrapper. */
|
||
|
|
||
|
#define ERR1 "\\ at end of pattern"
|
||
|
#define ERR2 "\\c at end of pattern"
|
||
|
#define ERR3 "unrecognized character follows \\"
|
||
|
#define ERR4 "numbers out of order in {} quantifier"
|
||
|
#define ERR5 "number too big in {} quantifier"
|
||
|
#define ERR6 "missing terminating ] for character class"
|
||
|
#define ERR7 "invalid escape sequence in character class"
|
||
|
#define ERR8 "range out of order in character class"
|
||
|
#define ERR9 "nothing to repeat"
|
||
|
#define ERR10 "operand of unlimited repeat could match the empty string"
|
||
|
#define ERR11 "internal error: unexpected repeat"
|
||
|
#define ERR12 "unrecognized character after (?"
|
||
|
#define ERR13 "too many capturing parenthesized sub-patterns"
|
||
|
#define ERR14 "missing )"
|
||
|
#define ERR15 "back reference to non-existent subpattern"
|
||
|
#define ERR16 "erroffset passed as NULL"
|
||
|
#define ERR17 "unknown option bit(s) set"
|
||
|
#define ERR18 "missing ) after comment"
|
||
|
#define ERR19 "too many sets of parentheses"
|
||
|
#define ERR20 "regular expression too large"
|
||
|
#define ERR21 "failed to get memory"
|
||
|
#define ERR22 "unmatched parentheses"
|
||
|
#define ERR23 "internal error: code overflow"
|
||
|
#define ERR24 "unrecognized character after (?<"
|
||
|
#define ERR25 "lookbehind assertion is not fixed length"
|
||
|
#define ERR26 "malformed number after (?("
|
||
|
#define ERR27 "conditional group contains more than two branches"
|
||
|
#define ERR28 "assertion expected after (?("
|
||
|
#define ERR29 "(?p must be followed by )"
|
||
|
#define ERR30 "unknown POSIX class name"
|
||
|
#define ERR31 "POSIX collating elements are not supported"
|
||
|
#define ERR32 "this version of PCRE is not compiled with PCRE_UTF8 support"
|
||
|
#define ERR33 "characters with values > 255 are not yet supported in classes"
|
||
|
#define ERR34 "character value in \\x{...} sequence is too large"
|
||
|
#define ERR35 "invalid condition (?(0)"
|
||
|
|
||
|
/* All character handling must be done as unsigned characters. Otherwise there
|
||
|
are problems with top-bit-set characters and functions such as isspace().
|
||
|
However, we leave the interface to the outside world as char *, because that
|
||
|
should make things easier for callers. We define a short type for unsigned char
|
||
|
to save lots of typing. I tried "uchar", but it causes problems on Digital
|
||
|
Unix, where it is defined in sys/types, so use "uschar" instead. */
|
||
|
|
||
|
typedef unsigned char uschar;
|
||
|
|
||
|
/* The real format of the start of the pcre block; the actual code vector
|
||
|
runs on as long as necessary after the end. */
|
||
|
|
||
|
typedef struct real_pcre {
|
||
|
unsigned long int magic_number;
|
||
|
size_t size;
|
||
|
const unsigned char *tables;
|
||
|
unsigned long int options;
|
||
|
uschar top_bracket;
|
||
|
uschar top_backref;
|
||
|
uschar first_char;
|
||
|
uschar req_char;
|
||
|
uschar code[1];
|
||
|
} real_pcre;
|
||
|
|
||
|
/* The real format of the extra block returned by pcre_study(). */
|
||
|
|
||
|
typedef struct real_pcre_extra {
|
||
|
uschar options;
|
||
|
uschar start_bits[32];
|
||
|
} real_pcre_extra;
|
||
|
|
||
|
|
||
|
/* Structure for passing "static" information around between the functions
|
||
|
doing the compiling, so that they are thread-safe. */
|
||
|
|
||
|
typedef struct compile_data {
|
||
|
const uschar *lcc; /* Points to lower casing table */
|
||
|
const uschar *fcc; /* Points to case-flipping table */
|
||
|
const uschar *cbits; /* Points to character type table */
|
||
|
const uschar *ctypes; /* Points to table of type maps */
|
||
|
} compile_data;
|
||
|
|
||
|
/* Structure for passing "static" information around between the functions
|
||
|
doing the matching, so that they are thread-safe. */
|
||
|
|
||
|
typedef struct match_data {
|
||
|
int errorcode; /* As it says */
|
||
|
int *offset_vector; /* Offset vector */
|
||
|
int offset_end; /* One past the end */
|
||
|
int offset_max; /* The maximum usable for return data */
|
||
|
const uschar *lcc; /* Points to lower casing table */
|
||
|
const uschar *ctypes; /* Points to table of type maps */
|
||
|
BOOL offset_overflow; /* Set if too many extractions */
|
||
|
BOOL notbol; /* NOTBOL flag */
|
||
|
BOOL noteol; /* NOTEOL flag */
|
||
|
BOOL utf8; /* UTF8 flag */
|
||
|
BOOL endonly; /* Dollar not before final \n */
|
||
|
BOOL notempty; /* Empty string match not wanted */
|
||
|
const uschar *start_pattern; /* For use when recursing */
|
||
|
const uschar *start_subject; /* Start of the subject string */
|
||
|
const uschar *end_subject; /* End of the subject string */
|
||
|
const uschar *start_match; /* Start of this match attempt */
|
||
|
const uschar *end_match_ptr; /* Subject position at end match */
|
||
|
int end_offset_top; /* Highwater mark at end of match */
|
||
|
} match_data;
|
||
|
|
||
|
/* Bit definitions for entries in the pcre_ctypes table. */
|
||
|
|
||
|
#define ctype_space 0x01
|
||
|
#define ctype_letter 0x02
|
||
|
#define ctype_digit 0x04
|
||
|
#define ctype_xdigit 0x08
|
||
|
#define ctype_word 0x10 /* alphameric or '_' */
|
||
|
#define ctype_meta 0x80 /* regexp meta char or zero (end pattern) */
|
||
|
|
||
|
/* Offsets for the bitmap tables in pcre_cbits. Each table contains a set
|
||
|
of bits for a class map. Some classes are built by combining these tables. */
|
||
|
|
||
|
#define cbit_space 0 /* [:space:] or \s */
|
||
|
#define cbit_xdigit 32 /* [:xdigit:] */
|
||
|
#define cbit_digit 64 /* [:digit:] or \d */
|
||
|
#define cbit_upper 96 /* [:upper:] */
|
||
|
#define cbit_lower 128 /* [:lower:] */
|
||
|
#define cbit_word 160 /* [:word:] or \w */
|
||
|
#define cbit_graph 192 /* [:graph:] */
|
||
|
#define cbit_print 224 /* [:print:] */
|
||
|
#define cbit_punct 256 /* [:punct:] */
|
||
|
#define cbit_cntrl 288 /* [:cntrl:] */
|
||
|
#define cbit_length 320 /* Length of the cbits table */
|
||
|
|
||
|
/* Offsets of the various tables from the base tables pointer, and
|
||
|
total length. */
|
||
|
|
||
|
#define lcc_offset 0
|
||
|
#define fcc_offset 256
|
||
|
#define cbits_offset 512
|
||
|
#define ctypes_offset (cbits_offset + cbit_length)
|
||
|
#define tables_length (ctypes_offset + 256)
|
||
|
|
||
|
/* End of internal.h */
|