code/trunk/internal.h

/*************************************************
*      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) 1997-1999 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. */

/* To cope with SunOS4 and other systems that lack memmove() but have bcopy(),
define a macro for memmove() if USE_BCOPY is defined. */

#ifdef USE_BCOPY
#undef  memmove        /* some systems may have a macro */
#define memmove(a, b, c) bcopy(b, a, c)
#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)

#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_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 (?("

/* 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;
  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   endonly;               /* Dollar not before final \n */
  BOOL   notempty;              /* Empty string match not wanted */
  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. */

#define cbit_digit    0      /* for \d */
#define cbit_word    32      /* for \w */
#define cbit_space   64      /* for \s */
#define cbit_length  96      /* 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 */
1	nigel	3	/*************************************************
2			* Perl-Compatible Regular Expressions *
3			*************************************************/
4
5
6			/* This is a library of functions to support regular expressions whose syntax
7			and semantics are as close as possible to those of the Perl 5 language. See
8			the file Tech.Notes for some information on the internals.
9
10			Written by: Philip Hazel <ph10@cam.ac.uk>
11
12	nigel	27	Copyright (c) 1997-1999 University of Cambridge
13	nigel	3
14			-----------------------------------------------------------------------------
15			Permission is granted to anyone to use this software for any purpose on any
16			computer system, and to redistribute it freely, subject to the following
17			restrictions:
18
19			1. This software is distributed in the hope that it will be useful,
20			but WITHOUT ANY WARRANTY; without even the implied warranty of
21			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22
23			2. The origin of this software must not be misrepresented, either by
24			explicit claim or by omission.
25
26			3. Altered versions must be plainly marked as such, and must not be
27			misrepresented as being the original software.
28	nigel	29
29			4. If PCRE is embedded in any software that is released under the GNU
30			General Purpose Licence (GPL), then the terms of that licence shall
31			supersede any condition above with which it is incompatible.
32	nigel	3	-----------------------------------------------------------------------------
33			*/
34
35			/* This header contains definitions that are shared between the different
36			modules, but which are not relevant to the outside. */
37
38			/* To cope with SunOS4 and other systems that lack memmove() but have bcopy(),
39			define a macro for memmove() if USE_BCOPY is defined. */
40
41			#ifdef USE_BCOPY
42	nigel	9	#undef memmove /* some systems may have a macro */
43	nigel	3	#define memmove(a, b, c) bcopy(b, a, c)
44			#endif
45
46			/* Standard C headers plus the external interface definition */
47
48			#include <ctype.h>
49			#include <limits.h>
50			#include <stddef.h>
51			#include <stdio.h>
52			#include <stdlib.h>
53			#include <string.h>
54			#include "pcre.h"
55
56	nigel	9	/* In case there is no definition of offsetof() provided - though any proper
57			Standard C system should have one. */
58
59			#ifndef offsetof
60	nigel	11	#define offsetof(p_type,field) ((size_t)&(((p_type *)0)->field))
61	nigel	9	#endif
62
63	nigel	23	/* These are the public options that can change during matching. */
64
65			#define PCRE_IMS (PCRE_CASELESS\|PCRE_MULTILINE\|PCRE_DOTALL)
66
67	nigel	37	/* Private options flags start at the most significant end of the four bytes,
68			but skip the top bit so we can use ints for convenience without getting tangled
69			with negative values. The public options defined in pcre.h start at the least
70			significant end. Make sure they don't overlap, though now that we have expanded
71			to four bytes there is plenty of space. */
72	nigel	3
73	nigel	37	#define PCRE_FIRSTSET 0x40000000 /* first_char is set */
74			#define PCRE_REQCHSET 0x20000000 /* req_char is set */
75			#define PCRE_STARTLINE 0x10000000 /* start after \n for multiline */
76			#define PCRE_INGROUP 0x08000000 /* compiling inside a group */
77			#define PCRE_ICHANGED 0x04000000 /* i option changes within regex */
78	nigel	3
79			/* Options for the "extra" block produced by pcre_study(). */
80
81	nigel	23	#define PCRE_STUDY_MAPPED 0x01 /* a map of starting chars exists */
82	nigel	3
83	nigel	23	/* Masks for identifying the public options which are permitted at compile
84			time, run time or study time, respectively. */
85	nigel	3
86			#define PUBLIC_OPTIONS \
87			(PCRE_CASELESS\|PCRE_EXTENDED\|PCRE_ANCHORED\|PCRE_MULTILINE\| \
88	nigel	19	PCRE_DOTALL\|PCRE_DOLLAR_ENDONLY\|PCRE_EXTRA\|PCRE_UNGREEDY)
89	nigel	3
90	nigel	37	#define PUBLIC_EXEC_OPTIONS \
91			(PCRE_ANCHORED\|PCRE_NOTBOL\|PCRE_NOTEOL\|PCRE_NOTEMPTY)
92	nigel	3
93	nigel	23	#define PUBLIC_STUDY_OPTIONS 0 /* None defined */
94	nigel	3
95			/* Magic number to provide a small check against being handed junk. */
96
97	nigel	33	#define MAGIC_NUMBER 0x50435245UL /* 'PCRE' */
98	nigel	3
99			/* Miscellaneous definitions */
100
101			typedef int BOOL;
102
103			#define FALSE 0
104			#define TRUE 1
105
106			/* These are escaped items that aren't just an encoding of a particular data
107			value such as \n. They must have non-zero values, as check_escape() returns
108			their negation. Also, they must appear in the same order as in the opcode
109	nigel	23	definitions below, up to ESC_z. The final one must be ESC_REF as subsequent
110	nigel	3	values are used for \1, \2, \3, etc. There is a test in the code for an escape
111			greater than ESC_b and less than ESC_X to detect the types that may be
112			repeated. If any new escapes are put in-between that don't consume a character,
113			that code will have to change. */
114
115			enum { ESC_A = 1, ESC_B, ESC_b, ESC_D, ESC_d, ESC_S, ESC_s, ESC_W, ESC_w,
116	nigel	23	ESC_Z, ESC_z, ESC_REF };
117	nigel	3
118			/* Opcode table: OP_BRA must be last, as all values >= it are used for brackets
119			that extract substrings. Starting from 1 (i.e. after OP_END), the values up to
120	nigel	7	OP_EOD must correspond in order to the list of escapes immediately above. */
121	nigel	3
122			enum {
123			OP_END, /* End of pattern */
124
125			/* Values corresponding to backslashed metacharacters */
126
127			OP_SOD, /* Start of data: \A */
128			OP_NOT_WORD_BOUNDARY, /* \B */
129			OP_WORD_BOUNDARY, /* \b */
130			OP_NOT_DIGIT, /* \D */
131			OP_DIGIT, /* \d */
132			OP_NOT_WHITESPACE, /* \S */
133			OP_WHITESPACE, /* \s */
134			OP_NOT_WORDCHAR, /* \W */
135			OP_WORDCHAR, /* \w */
136	nigel	23	OP_EODN, /* End of data or \n at end of data: \Z. */
137			OP_EOD, /* End of data: \z */
138	nigel	3
139	nigel	23	OP_OPT, /* Set runtime options */
140	nigel	3	OP_CIRC, /* Start of line - varies with multiline switch */
141			OP_DOLL, /* End of line - varies with multiline switch */
142			OP_ANY, /* Match any character */
143			OP_CHARS, /* Match string of characters */
144			OP_NOT, /* Match anything but the following char */
145
146			OP_STAR, /* The maximizing and minimizing versions of */
147			OP_MINSTAR, /* all these opcodes must come in pairs, with */
148			OP_PLUS, /* the minimizing one second. */
149			OP_MINPLUS, /* This first set applies to single characters */
150			OP_QUERY,
151			OP_MINQUERY,
152			OP_UPTO, /* From 0 to n matches */
153			OP_MINUPTO,
154			OP_EXACT, /* Exactly n matches */
155
156			OP_NOTSTAR, /* The maximizing and minimizing versions of */
157			OP_NOTMINSTAR, /* all these opcodes must come in pairs, with */
158			OP_NOTPLUS, /* the minimizing one second. */
159			OP_NOTMINPLUS, /* This first set applies to "not" single characters */
160			OP_NOTQUERY,
161			OP_NOTMINQUERY,
162			OP_NOTUPTO, /* From 0 to n matches */
163			OP_NOTMINUPTO,
164			OP_NOTEXACT, /* Exactly n matches */
165
166			OP_TYPESTAR, /* The maximizing and minimizing versions of */
167			OP_TYPEMINSTAR, /* all these opcodes must come in pairs, with */
168			OP_TYPEPLUS, /* the minimizing one second. These codes must */
169			OP_TYPEMINPLUS, /* be in exactly the same order as those above. */
170			OP_TYPEQUERY, /* This set applies to character types such as \d */
171			OP_TYPEMINQUERY,
172			OP_TYPEUPTO, /* From 0 to n matches */
173			OP_TYPEMINUPTO,
174			OP_TYPEEXACT, /* Exactly n matches */
175
176			OP_CRSTAR, /* The maximizing and minimizing versions of */
177			OP_CRMINSTAR, /* all these opcodes must come in pairs, with */
178			OP_CRPLUS, /* the minimizing one second. These codes must */
179			OP_CRMINPLUS, /* be in exactly the same order as those above. */
180			OP_CRQUERY, /* These are for character classes and back refs */
181			OP_CRMINQUERY,
182			OP_CRRANGE, /* These are different to the three seta above. */
183			OP_CRMINRANGE,
184
185			OP_CLASS, /* Match a character class */
186			OP_REF, /* Match a back reference */
187
188			OP_ALT, /* Start of alternation */
189			OP_KET, /* End of group that doesn't have an unbounded repeat */
190			OP_KETRMAX, /* These two must remain together and in this */
191			OP_KETRMIN, /* order. They are for groups the repeat for ever. */
192
193	nigel	23	/* The assertions must come before ONCE and COND */
194
195			OP_ASSERT, /* Positive lookahead */
196			OP_ASSERT_NOT, /* Negative lookahead */
197			OP_ASSERTBACK, /* Positive lookbehind */
198			OP_ASSERTBACK_NOT, /* Negative lookbehind */
199			OP_REVERSE, /* Move pointer back - used in lookbehind assertions */
200
201			/* ONCE and COND must come after the assertions, with ONCE first, as there's
202			a test for >= ONCE for a subpattern that isn't an assertion. */
203
204	nigel	3	OP_ONCE, /* Once matched, don't back up into the subpattern */
205	nigel	23	OP_COND, /* Conditional group */
206			OP_CREF, /* Used to hold an extraction string number */
207	nigel	3
208			OP_BRAZERO, /* These two must remain together and in this */
209			OP_BRAMINZERO, /* order. */
210
211			OP_BRA /* This and greater values are used for brackets that
212			extract substrings. */
213			};
214
215			/* The highest extraction number. This is limited by the number of opcodes
216			left after OP_BRA, i.e. 255 - OP_BRA. We actually set it somewhat lower. */
217
218			#define EXTRACT_MAX 99
219
220			/* The texts of compile-time error messages are defined as macros here so that
221			they can be accessed by the POSIX wrapper and converted into error codes. Yes,
222			I could have used error codes in the first place, but didn't feel like changing
223			just to accommodate the POSIX wrapper. */
224
225			#define ERR1 "\\ at end of pattern"
226			#define ERR2 "\\c at end of pattern"
227			#define ERR3 "unrecognized character follows \\"
228			#define ERR4 "numbers out of order in {} quantifier"
229			#define ERR5 "number too big in {} quantifier"
230			#define ERR6 "missing terminating ] for character class"
231			#define ERR7 "invalid escape sequence in character class"
232			#define ERR8 "range out of order in character class"
233			#define ERR9 "nothing to repeat"
234			#define ERR10 "operand of unlimited repeat could match the empty string"
235			#define ERR11 "internal error: unexpected repeat"
236			#define ERR12 "unrecognized character after (?"
237			#define ERR13 "too many capturing parenthesized sub-patterns"
238			#define ERR14 "missing )"
239			#define ERR15 "back reference to non-existent subpattern"
240			#define ERR16 "erroffset passed as NULL"
241			#define ERR17 "unknown option bit(s) set"
242			#define ERR18 "missing ) after comment"
243			#define ERR19 "too many sets of parentheses"
244			#define ERR20 "regular expression too large"
245			#define ERR21 "failed to get memory"
246	nigel	23	#define ERR22 "unmatched parentheses"
247	nigel	3	#define ERR23 "internal error: code overflow"
248	nigel	23	#define ERR24 "unrecognized character after (?<"
249			#define ERR25 "lookbehind assertion is not fixed length"
250			#define ERR26 "malformed number after (?("
251			#define ERR27 "conditional group contains more than two branches"
252			#define ERR28 "assertion expected after (?("
253	nigel	3
254			/* All character handling must be done as unsigned characters. Otherwise there
255			are problems with top-bit-set characters and functions such as isspace().
256			However, we leave the interface to the outside world as char *, because that
257			should make things easier for callers. We define a short type for unsigned char
258			to save lots of typing. I tried "uchar", but it causes problems on Digital
259			Unix, where it is defined in sys/types, so use "uschar" instead. */
260
261			typedef unsigned char uschar;
262
263			/* The real format of the start of the pcre block; the actual code vector
264			runs on as long as necessary after the end. */
265
266			typedef struct real_pcre {
267	nigel	33	unsigned long int magic_number;
268	nigel	25	const unsigned char *tables;
269	nigel	37	unsigned long int options;
270			uschar top_bracket;
271			uschar top_backref;
272			uschar first_char;
273			uschar req_char;
274			uschar code[1];
275	nigel	3	} real_pcre;
276
277			/* The real format of the extra block returned by pcre_study(). */
278
279			typedef struct real_pcre_extra {
280	nigel	37	uschar options;
281			uschar start_bits[32];
282	nigel	3	} real_pcre_extra;
283
284
285	nigel	25	/* Structure for passing "static" information around between the functions
286			doing the compiling, so that they are thread-safe. */
287	nigel	3
288	nigel	25	typedef struct compile_data {
289			const uschar lcc; / Points to lower casing table */
290	nigel	37	const uschar fcc; / Points to case-flipping table */
291	nigel	25	const uschar cbits; / Points to character type table */
292			const uschar ctypes; / Points to table of type maps */
293			} compile_data;
294	nigel	3
295	nigel	25	/* Structure for passing "static" information around between the functions
296			doing the matching, so that they are thread-safe. */
297
298			typedef struct match_data {
299			int errorcode; /* As it says */
300			int offset_vector; / Offset vector */
301			int offset_end; /* One past the end */
302			int offset_max; /* The maximum usable for return data */
303			const uschar lcc; / Points to lower casing table */
304			const uschar ctypes; / Points to table of type maps */
305			BOOL offset_overflow; /* Set if too many extractions */
306			BOOL notbol; /* NOTBOL flag */
307			BOOL noteol; /* NOTEOL flag */
308			BOOL endonly; /* Dollar not before final \n */
309	nigel	37	BOOL notempty; /* Empty string match not wanted */
310	nigel	25	const uschar start_subject; / Start of the subject string */
311			const uschar end_subject; / End of the subject string */
312	nigel	37	const uschar start_match; / Start of this match attempt */
313	nigel	25	const uschar end_match_ptr; / Subject position at end match */
314			int end_offset_top; /* Highwater mark at end of match */
315			} match_data;
316
317			/* Bit definitions for entries in the pcre_ctypes table. */
318
319	nigel	3	#define ctype_space 0x01
320			#define ctype_letter 0x02
321			#define ctype_digit 0x04
322			#define ctype_xdigit 0x08
323			#define ctype_word 0x10 /* alphameric or '_' */
324			#define ctype_meta 0x80 /* regexp meta char or zero (end pattern) */
325
326	nigel	25	/* Offsets for the bitmap tables in pcre_cbits. Each table contains a set
327			of bits for a class map. */
328	nigel	3
329	nigel	25	#define cbit_digit 0 /* for \d */
330			#define cbit_word 32 /* for \w */
331			#define cbit_space 64 /* for \s */
332			#define cbit_length 96 /* Length of the cbits table */
333	nigel	3
334	nigel	25	/* Offsets of the various tables from the base tables pointer, and
335			total length. */
336
337			#define lcc_offset 0
338			#define fcc_offset 256
339			#define cbits_offset 512
340			#define ctypes_offset (cbits_offset + cbit_length)
341			#define tables_length (ctypes_offset + 256)
342
343	nigel	3	/* End of internal.h */