init

pg_include/regex/regcustom.h

@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 1998, 1999 Henry Spencer.	All rights reserved.
+ *
+ * Development of this software was funded, in part, by Cray Research Inc.,
+ * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
+ * Corporation, none of whom are responsible for the results.  The author
+ * thanks all of them.
+ *
+ * Redistribution and use in source and binary forms -- with or without
+ * modification -- are permitted for any purpose, provided that
+ * redistributions in source form retain this entire copyright notice and
+ * indicate the origin and nature of any modifications.
+ *
+ * I'd appreciate being given credit for this package in the documentation
+ * of software which uses it, but that is not a requirement.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
+ * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * src/include/regex/regcustom.h
+ */
+
+/* headers if any */
+#include "postgres.h"
+
+#include <ctype.h>
+#include <limits.h>
+
+/*
+ * towlower() and friends should be in <wctype.h>, but some pre-C99 systems
+ * declare them in <wchar.h>.
+ */
+#ifdef HAVE_WCHAR_H
+#include <wchar.h>
+#endif
+#ifdef HAVE_WCTYPE_H
+#include <wctype.h>
+#endif
+
+#include "mb/pg_wchar.h"
+
+
+/* overrides for regguts.h definitions, if any */
+#define FUNCPTR(name, args) (*name) args
+#define MALLOC(n)		malloc(n)
+#define FREE(p)			free(VS(p))
+#define REALLOC(p,n)	realloc(VS(p),n)
+#define assert(x)		Assert(x)
+
+/* internal character type and related */
+typedef pg_wchar chr;			/* the type itself */
+typedef unsigned uchr;			/* unsigned type that will hold a chr */
+typedef int celt;				/* type to hold chr, or NOCELT */
+
+#define NOCELT	(-1)			/* celt value which is not valid chr */
+#define CHR(c)	((unsigned char) (c))	/* turn char literal into chr literal */
+#define DIGITVAL(c) ((c)-'0')	/* turn chr digit into its value */
+#define CHRBITS 32				/* bits in a chr; must not use sizeof */
+#define CHR_MIN 0x00000000		/* smallest and largest chr; the value */
+#define CHR_MAX 0xfffffffe		/* CHR_MAX-CHR_MIN+1 should fit in uchr */
+
+/* functions operating on chr */
+#define iscalnum(x) pg_wc_isalnum(x)
+#define iscalpha(x) pg_wc_isalpha(x)
+#define iscdigit(x) pg_wc_isdigit(x)
+#define iscspace(x) pg_wc_isspace(x)
+
+/* and pick up the standard header */
+#include "regex.h"

pg_include/regex/regerrs.h

@@ -0,0 +1,79 @@
+/*
+ * src/include/regex/regerrs.h
+ */
+
+{
+	REG_OKAY, "REG_OKAY", "no errors detected"
+},
+
+{
+	REG_NOMATCH, "REG_NOMATCH", "failed to match"
+},
+
+{
+	REG_BADPAT, "REG_BADPAT", "invalid regexp (reg version 0.8)"
+},
+
+{
+	REG_ECOLLATE, "REG_ECOLLATE", "invalid collating element"
+},
+
+{
+	REG_ECTYPE, "REG_ECTYPE", "invalid character class"
+},
+
+{
+	REG_EESCAPE, "REG_EESCAPE", "invalid escape \\ sequence"
+},
+
+{
+	REG_ESUBREG, "REG_ESUBREG", "invalid backreference number"
+},
+
+{
+	REG_EBRACK, "REG_EBRACK", "brackets [] not balanced"
+},
+
+{
+	REG_EPAREN, "REG_EPAREN", "parentheses () not balanced"
+},
+
+{
+	REG_EBRACE, "REG_EBRACE", "braces {} not balanced"
+},
+
+{
+	REG_BADBR, "REG_BADBR", "invalid repetition count(s)"
+},
+
+{
+	REG_ERANGE, "REG_ERANGE", "invalid character range"
+},
+
+{
+	REG_ESPACE, "REG_ESPACE", "out of memory"
+},
+
+{
+	REG_BADRPT, "REG_BADRPT", "quantifier operand invalid"
+},
+
+{
+	REG_ASSERT, "REG_ASSERT", "\"cannot happen\" -- you found a bug"
+},
+
+{
+	REG_INVARG, "REG_INVARG", "invalid argument to regex function"
+},
+
+{
+	REG_MIXED, "REG_MIXED", "character widths of regex and string differ"
+},
+
+{
+	REG_BADOPT, "REG_BADOPT", "invalid embedded option"
+},
+
+{
+	REG_ETOOBIG, "REG_ETOOBIG", "nfa has too many states"
+},

pg_include/regex/regex.h

@@ -0,0 +1,175 @@
+#ifndef _REGEX_H_
+#define _REGEX_H_				/* never again */
+/*
+ * regular expressions
+ *
+ * Copyright (c) 1998, 1999 Henry Spencer.	All rights reserved.
+ *
+ * Development of this software was funded, in part, by Cray Research Inc.,
+ * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
+ * Corporation, none of whom are responsible for the results.  The author
+ * thanks all of them.
+ *
+ * Redistribution and use in source and binary forms -- with or without
+ * modification -- are permitted for any purpose, provided that
+ * redistributions in source form retain this entire copyright notice and
+ * indicate the origin and nature of any modifications.
+ *
+ * I'd appreciate being given credit for this package in the documentation
+ * of software which uses it, but that is not a requirement.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
+ * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * src/include/regex/regex.h
+ */
+
+/*
+ * Add your own defines, if needed, here.
+ */
+#include "mb/pg_wchar.h"
+
+/*
+ * interface types etc.
+ */
+
+/*
+ * regoff_t has to be large enough to hold either off_t or ssize_t,
+ * and must be signed; it's only a guess that long is suitable.
+ */
+typedef long regoff_t;
+
+/*
+ * other interface types
+ */
+
+/* the biggie, a compiled RE (or rather, a front end to same) */
+typedef struct
+{
+	int			re_magic;		/* magic number */
+	size_t		re_nsub;		/* number of subexpressions */
+	long		re_info;		/* information about RE */
+#define  REG_UBACKREF		 000001
+#define  REG_ULOOKAHEAD		 000002
+#define  REG_UBOUNDS	 000004
+#define  REG_UBRACES	 000010
+#define  REG_UBSALNUM		 000020
+#define  REG_UPBOTCH	 000040
+#define  REG_UBBS		 000100
+#define  REG_UNONPOSIX		 000200
+#define  REG_UUNSPEC	 000400
+#define  REG_UUNPORT	 001000
+#define  REG_ULOCALE	 002000
+#define  REG_UEMPTYMATCH	 004000
+#define  REG_UIMPOSSIBLE	 010000
+#define  REG_USHORTEST		 020000
+	int			re_csize;		/* sizeof(character) */
+	char	   *re_endp;		/* backward compatibility kludge */
+	Oid			re_collation;	/* Collation that defines LC_CTYPE behavior */
+	/* the rest is opaque pointers to hidden innards */
+	char	   *re_guts;		/* `char *' is more portable than `void *' */
+	char	   *re_fns;
+} regex_t;
+
+/* result reporting (may acquire more fields later) */
+typedef struct
+{
+	regoff_t	rm_so;			/* start of substring */
+	regoff_t	rm_eo;			/* end of substring */
+} regmatch_t;
+
+/* supplementary control and reporting */
+typedef struct
+{
+	regmatch_t	rm_extend;		/* see REG_EXPECT */
+} rm_detail_t;
+
+
+
+/*
+ * regex compilation flags
+ */
+#define REG_BASIC	000000		/* BREs (convenience) */
+#define REG_EXTENDED	000001	/* EREs */
+#define REG_ADVF	000002		/* advanced features in EREs */
+#define REG_ADVANCED	000003	/* AREs (which are also EREs) */
+#define REG_QUOTE	000004		/* no special characters, none */
+#define REG_NOSPEC	REG_QUOTE	/* historical synonym */
+#define REG_ICASE	000010		/* ignore case */
+#define REG_NOSUB	000020		/* don't care about subexpressions */
+#define REG_EXPANDED	000040	/* expanded format, white space & comments */
+#define REG_NLSTOP	000100		/* \n doesn't match . or [^ ] */
+#define REG_NLANCH	000200		/* ^ matches after \n, $ before */
+#define REG_NEWLINE 000300		/* newlines are line terminators */
+#define REG_PEND	000400		/* ugh -- backward-compatibility hack */
+#define REG_EXPECT	001000		/* report details on partial/limited matches */
+#define REG_BOSONLY 002000		/* temporary kludge for BOS-only matches */
+#define REG_DUMP	004000		/* none of your business :-) */
+#define REG_FAKE	010000		/* none of your business :-) */
+#define REG_PROGRESS	020000	/* none of your business :-) */
+
+
+
+/*
+ * regex execution flags
+ */
+#define REG_NOTBOL	0001		/* BOS is not BOL */
+#define REG_NOTEOL	0002		/* EOS is not EOL */
+#define REG_STARTEND	0004	/* backward compatibility kludge */
+#define REG_FTRACE	0010		/* none of your business */
+#define REG_MTRACE	0020		/* none of your business */
+#define REG_SMALL	0040		/* none of your business */
+
+
+/*
+ * error reporting
+ * Be careful if modifying the list of error codes -- the table used by
+ * regerror() is generated automatically from this file!
+ */
+#define REG_OKAY	 0			/* no errors detected */
+#define REG_NOMATCH  1			/* failed to match */
+#define REG_BADPAT	 2			/* invalid regexp */
+#define REG_ECOLLATE	 3		/* invalid collating element */
+#define REG_ECTYPE	 4			/* invalid character class */
+#define REG_EESCAPE  5			/* invalid escape \ sequence */
+#define REG_ESUBREG  6			/* invalid backreference number */
+#define REG_EBRACK	 7			/* brackets [] not balanced */
+#define REG_EPAREN	 8			/* parentheses () not balanced */
+#define REG_EBRACE	 9			/* braces {} not balanced */
+#define REG_BADBR	10			/* invalid repetition count(s) */
+#define REG_ERANGE	11			/* invalid character range */
+#define REG_ESPACE	12			/* out of memory */
+#define REG_BADRPT	13			/* quantifier operand invalid */
+#define REG_ASSERT	15			/* "can't happen" -- you found a bug */
+#define REG_INVARG	16			/* invalid argument to regex function */
+#define REG_MIXED	17			/* character widths of regex and string differ */
+#define REG_BADOPT	18			/* invalid embedded option */
+#define REG_ETOOBIG 19			/* nfa has too many states */
+/* two specials for debugging and testing */
+#define REG_ATOI	101			/* convert error-code name to number */
+#define REG_ITOA	102			/* convert error-code number to name */
+/* non-error result codes for pg_regprefix */
+#define REG_PREFIX	(-1)		/* identified a common prefix */
+#define REG_EXACT	(-2)		/* identified an exact match */
+
+
+
+/*
+ * the prototypes for exported functions
+ */
+extern int	pg_regcomp(regex_t *, const pg_wchar *, size_t, int, Oid);
+extern int	pg_regexec(regex_t *, const pg_wchar *, size_t, size_t, rm_detail_t *, size_t, regmatch_t[], int);
+extern int	pg_regprefix(regex_t *, pg_wchar **, size_t *);
+extern void pg_regfree(regex_t *);
+extern size_t pg_regerror(int, const regex_t *, char *, size_t);
+extern void pg_set_regex_collation(Oid collation);
+
+#endif   /* _REGEX_H_ */

pg_include/regex/regguts.h

@@ -0,0 +1,469 @@
+/*
+ * Internal interface definitions, etc., for the reg package
+ *
+ * Copyright (c) 1998, 1999 Henry Spencer.	All rights reserved.
+ *
+ * Development of this software was funded, in part, by Cray Research Inc.,
+ * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
+ * Corporation, none of whom are responsible for the results.  The author
+ * thanks all of them.
+ *
+ * Redistribution and use in source and binary forms -- with or without
+ * modification -- are permitted for any purpose, provided that
+ * redistributions in source form retain this entire copyright notice and
+ * indicate the origin and nature of any modifications.
+ *
+ * I'd appreciate being given credit for this package in the documentation
+ * of software which uses it, but that is not a requirement.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
+ * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * src/include/regex/regguts.h
+ */
+
+
+
+/*
+ * Environmental customization.  It should not (I hope) be necessary to
+ * alter the file you are now reading -- regcustom.h should handle it all,
+ * given care here and elsewhere.
+ */
+#include "regcustom.h"
+
+
+
+/*
+ * Things that regcustom.h might override.
+ */
+
+/* assertions */
+#ifndef assert
+#ifndef REG_DEBUG
+#define  NDEBUG					/* no assertions */
+#endif
+#include <assert.h>
+#endif
+
+/* voids */
+#ifndef DISCARD
+#define DISCARD void			/* for throwing values away */
+#endif
+#ifndef VS
+#define VS(x)	((void *)(x))	/* cast something to generic ptr */
+#endif
+
+/* function-pointer declarator */
+#ifndef FUNCPTR
+#define FUNCPTR(name, args) (*(name)) args
+#endif
+
+/* memory allocation */
+#ifndef MALLOC
+#define MALLOC(n)	malloc(n)
+#endif
+#ifndef REALLOC
+#define REALLOC(p, n)	realloc(VS(p), n)
+#endif
+#ifndef FREE
+#define FREE(p)		free(VS(p))
+#endif
+
+/* want size of a char in bits, and max value in bounded quantifiers */
+#ifndef CHAR_BIT
+#include <limits.h>
+#endif
+#ifndef _POSIX2_RE_DUP_MAX
+#define _POSIX2_RE_DUP_MAX	255 /* normally from <limits.h> */
+#endif
+
+
+
+/*
+ * misc
+ */
+
+#define NOTREACHED	0
+#define xxx		1
+
+#define DUPMAX	_POSIX2_RE_DUP_MAX
+#define INFINITY	(DUPMAX+1)
+
+#define REMAGIC 0xfed7			/* magic number for main struct */
+
+
+
+/*
+ * debugging facilities
+ */
+#ifdef REG_DEBUG
+/* FDEBUG does finite-state tracing */
+#define FDEBUG(arglist) { if (v->eflags&REG_FTRACE) printf arglist; }
+/* MDEBUG does higher-level tracing */
+#define MDEBUG(arglist) { if (v->eflags&REG_MTRACE) printf arglist; }
+#else
+#define FDEBUG(arglist) {}
+#define MDEBUG(arglist) {}
+#endif
+
+
+
+/*
+ * bitmap manipulation
+ */
+#define UBITS	(CHAR_BIT * sizeof(unsigned))
+#define BSET(uv, sn)	((uv)[(sn)/UBITS] |= (unsigned)1 << ((sn)%UBITS))
+#define ISBSET(uv, sn)	((uv)[(sn)/UBITS] & ((unsigned)1 << ((sn)%UBITS)))
+
+
+
+/*
+ * We dissect a chr into byts for colormap table indexing.	Here we define
+ * a byt, which will be the same as a byte on most machines...	The exact
+ * size of a byt is not critical, but about 8 bits is good, and extraction
+ * of 8-bit chunks is sometimes especially fast.
+ */
+#ifndef BYTBITS
+#define BYTBITS 8				/* bits in a byt */
+#endif
+#define BYTTAB	(1<<BYTBITS)	/* size of table with one entry per byt value */
+#define BYTMASK (BYTTAB-1)		/* bit mask for byt */
+#define NBYTS	((CHRBITS+BYTBITS-1)/BYTBITS)
+/* the definition of GETCOLOR(), below, assumes NBYTS <= 4 */
+
+
+
+/*
+ * As soon as possible, we map chrs into equivalence classes -- "colors" --
+ * which are of much more manageable number.
+ */
+typedef short color;			/* colors of characters */
+typedef int pcolor;				/* what color promotes to */
+
+#define COLORLESS	(-1)		/* impossible color */
+#define WHITE		0			/* default color, parent of all others */
+
+
+
+/*
+ * A colormap is a tree -- more precisely, a DAG -- indexed at each level
+ * by a byt of the chr, to map the chr to a color efficiently.	Because
+ * lower sections of the tree can be shared, it can exploit the usual
+ * sparseness of such a mapping table.	The tree is always NBYTS levels
+ * deep (in the past it was shallower during construction but was "filled"
+ * to full depth at the end of that); areas that are unaltered as yet point
+ * to "fill blocks" which are entirely WHITE in color.
+ */
+
+/* the tree itself */
+struct colors
+{
+	color		ccolor[BYTTAB];
+};
+struct ptrs
+{
+	union tree *pptr[BYTTAB];
+};
+union tree
+{
+	struct colors colors;
+	struct ptrs ptrs;
+};
+
+#define tcolor	colors.ccolor
+#define tptr	ptrs.pptr
+
+/*
+ * Per-color data structure for the compile-time color machinery
+ *
+ * If "sub" is not NOSUB then it is the number of the color's current
+ * subcolor, i.e. we are in process of dividing this color (character
+ * equivalence class) into two colors.	See src/backend/regex/README for
+ * discussion of subcolors.
+ *
+ * Currently-unused colors have the FREECOL bit set and are linked into a
+ * freelist using their "sub" fields, but only if their color numbers are
+ * less than colormap.max.	Any array entries beyond "max" are just garbage.
+ */
+struct colordesc
+{
+	uchr		nchrs;			/* number of chars of this color */
+	color		sub;			/* open subcolor, if any; or free-chain ptr */
+#define  NOSUB	 COLORLESS		/* value of "sub" when no open subcolor */
+	struct arc *arcs;			/* chain of all arcs of this color */
+	chr			firstchr;		/* char first assigned to this color */
+	int			flags;			/* bit values defined next */
+#define  FREECOL 01				/* currently free */
+#define  PSEUDO  02				/* pseudocolor, no real chars */
+#define  UNUSEDCOLOR(cd) ((cd)->flags & FREECOL)
+	union tree *block;			/* block of solid color, if any */
+};
+
+/*
+ * The color map itself
+ *
+ * Much of the data in the colormap struct is only used at compile time.
+ * However, the bulk of the space usage is in the "tree" structure, so it's
+ * not clear that there's much point in converting the rest to a more compact
+ * form when compilation is finished.
+ */
+struct colormap
+{
+	int			magic;
+#define  CMMAGIC 0x876
+	struct vars *v;				/* for compile error reporting */
+	size_t		ncds;			/* allocated length of colordescs array */
+	size_t		max;			/* highest color number currently in use */
+	color		free;			/* beginning of free chain (if non-0) */
+	struct colordesc *cd;		/* pointer to array of colordescs */
+#define  CDEND(cm)	 (&(cm)->cd[(cm)->max + 1])
+	/* If we need up to NINLINECDS, we store them here to save a malloc */
+#define  NINLINECDS  ((size_t)10)
+	struct colordesc cdspace[NINLINECDS];
+	union tree	tree[NBYTS];	/* tree top, plus lower-level fill blocks */
+};
+
+/* optimization magic to do fast chr->color mapping */
+#define B0(c)	((c) & BYTMASK)
+#define B1(c)	(((c)>>BYTBITS) & BYTMASK)
+#define B2(c)	(((c)>>(2*BYTBITS)) & BYTMASK)
+#define B3(c)	(((c)>>(3*BYTBITS)) & BYTMASK)
+#if NBYTS == 1
+#define GETCOLOR(cm, c) ((cm)->tree->tcolor[B0(c)])
+#endif
+/* beware, for NBYTS>1, GETCOLOR() is unsafe -- 2nd arg used repeatedly */
+#if NBYTS == 2
+#define GETCOLOR(cm, c) ((cm)->tree->tptr[B1(c)]->tcolor[B0(c)])
+#endif
+#if NBYTS == 4
+#define GETCOLOR(cm, c) ((cm)->tree->tptr[B3(c)]->tptr[B2(c)]->tptr[B1(c)]->tcolor[B0(c)])
+#endif
+
+
+/*
+ * Interface definitions for locale-interface functions in regc_locale.c.
+ */
+
+/*
+ * Representation of a set of characters.  chrs[] represents individual
+ * code points, ranges[] represents ranges in the form min..max inclusive.
+ *
+ * Note that in cvecs gotten from newcvec() and intended to be freed by
+ * freecvec(), both arrays of chrs are after the end of the struct, not
+ * separately malloc'd; so chrspace and rangespace are effectively immutable.
+ */
+struct cvec
+{
+	int			nchrs;			/* number of chrs */
+	int			chrspace;		/* number of chrs allocated in chrs[] */
+	chr		   *chrs;			/* pointer to vector of chrs */
+	int			nranges;		/* number of ranges (chr pairs) */
+	int			rangespace;		/* number of ranges allocated in ranges[] */
+	chr		   *ranges;			/* pointer to vector of chr pairs */
+};
+
+
+/*
+ * definitions for NFA internal representation
+ *
+ * Having a "from" pointer within each arc may seem redundant, but it
+ * saves a lot of hassle.
+ */
+struct state;
+
+struct arc
+{
+	int			type;			/* 0 if free, else an NFA arc type code */
+	color		co;
+	struct state *from;			/* where it's from (and contained within) */
+	struct state *to;			/* where it's to */
+	struct arc *outchain;		/* link in *from's outs chain or free chain */
+#define  freechain	 outchain
+	struct arc *inchain;		/* link in *to's ins chain */
+	struct arc *colorchain;		/* link in color's arc chain */
+	struct arc *colorchainRev;	/* back-link in color's arc chain */
+};
+
+struct arcbatch
+{								/* for bulk allocation of arcs */
+	struct arcbatch *next;
+#define  ABSIZE  10
+	struct arc	a[ABSIZE];
+};
+
+struct state
+{
+	int			no;
+#define  FREESTATE	 (-1)
+	char		flag;			/* marks special states */
+	int			nins;			/* number of inarcs */
+	struct arc *ins;			/* chain of inarcs */
+	int			nouts;			/* number of outarcs */
+	struct arc *outs;			/* chain of outarcs */
+	struct arc *free;			/* chain of free arcs */
+	struct state *tmp;			/* temporary for traversal algorithms */
+	struct state *next;			/* chain for traversing all */
+	struct state *prev;			/* back chain */
+	struct arcbatch oas;		/* first arcbatch, avoid malloc in easy case */
+	int			noas;			/* number of arcs used in first arcbatch */
+};
+
+struct nfa
+{
+	struct state *pre;			/* pre-initial state */
+	struct state *init;			/* initial state */
+	struct state *final;		/* final state */
+	struct state *post;			/* post-final state */
+	int			nstates;		/* for numbering states */
+	struct state *states;		/* state-chain header */
+	struct state *slast;		/* tail of the chain */
+	struct state *free;			/* free list */
+	struct colormap *cm;		/* the color map */
+	color		bos[2];			/* colors, if any, assigned to BOS and BOL */
+	color		eos[2];			/* colors, if any, assigned to EOS and EOL */
+	size_t		size;			/* Current NFA size; differs from nstates as
+								 * it also counts the number of states created
+								 * by children of this state. */
+	struct vars *v;				/* simplifies compile error reporting */
+	struct nfa *parent;			/* parent NFA, if any */
+};
+
+
+
+/*
+ * definitions for compacted NFA
+ *
+ * The main space savings in a compacted NFA is from making the arcs as small
+ * as possible.  We store only the transition color and next-state number for
+ * each arc.  The list of out arcs for each state is an array beginning at
+ * cnfa.states[statenumber], and terminated by a dummy carc struct with
+ * co == COLORLESS.
+ *
+ * The non-dummy carc structs are of two types: plain arcs and LACON arcs.
+ * Plain arcs just store the transition color number as "co".  LACON arcs
+ * store the lookahead constraint number plus cnfa.ncolors as "co".  LACON
+ * arcs can be distinguished from plain by testing for co >= cnfa.ncolors.
+ */
+struct carc
+{
+	color		co;				/* COLORLESS is list terminator */
+	int			to;				/* next-state number */
+};
+
+struct cnfa
+{
+	int			nstates;		/* number of states */
+	int			ncolors;		/* number of colors (max color in use + 1) */
+	int			flags;
+#define  HASLACONS	01			/* uses lookahead constraints */
+	int			pre;			/* setup state number */
+	int			post;			/* teardown state number */
+	color		bos[2];			/* colors, if any, assigned to BOS and BOL */
+	color		eos[2];			/* colors, if any, assigned to EOS and EOL */
+	char	   *stflags;		/* vector of per-state flags bytes */
+#define  CNFA_NOPROGRESS	01	/* flag bit for a no-progress state */
+	struct carc **states;		/* vector of pointers to outarc lists */
+	/* states[n] are pointers into a single malloc'd array of arcs */
+	struct carc *arcs;			/* the area for the lists */
+};
+
+#define ZAPCNFA(cnfa)	((cnfa).nstates = 0)
+#define NULLCNFA(cnfa)	((cnfa).nstates == 0)
+
+/*
+ * Used to limit the maximum NFA size to something sane. [Tcl Bug 1810264]
+ */
+#ifndef REG_MAX_STATES
+#define REG_MAX_STATES	100000
+#endif
+
+/*
+ * subexpression tree
+ *
+ * "op" is one of:
+ *		'='  plain regex without interesting substructure (implemented as DFA)
+ *		'b'  back-reference (has no substructure either)
+ *		'('  capture node: captures the match of its single child
+ *		'.'  concatenation: matches a match for left, then a match for right
+ *		'|'  alternation: matches a match for left or a match for right
+ *		'*'  iteration: matches some number of matches of its single child
+ *
+ * Note: the right child of an alternation must be another alternation or
+ * NULL; hence, an N-way branch requires N alternation nodes, not N-1 as you
+ * might expect.  This could stand to be changed.  Actually I'd rather see
+ * a single alternation node with N children, but that will take revising
+ * the representation of struct subre.
+ *
+ * Note: when a backref is directly quantified, we stick the min/max counts
+ * into the backref rather than plastering an iteration node on top.  This is
+ * for efficiency: there is no need to search for possible division points.
+ */
+struct subre
+{
+	char		op;				/* see type codes above */
+	char		flags;
+#define  LONGER  01				/* prefers longer match */
+#define  SHORTER 02				/* prefers shorter match */
+#define  MIXED	 04				/* mixed preference below */
+#define  CAP 010				/* capturing parens below */
+#define  BACKR	 020			/* back reference below */
+#define  INUSE	 0100			/* in use in final tree */
+#define  LOCAL	 03				/* bits which may not propagate up */
+#define  LMIX(f) ((f)<<2)		/* LONGER -> MIXED */
+#define  SMIX(f) ((f)<<1)		/* SHORTER -> MIXED */
+#define  UP(f)	 (((f)&~LOCAL) | (LMIX(f) & SMIX(f) & MIXED))
+#define  MESSY(f)	 ((f)&(MIXED|CAP|BACKR))
+#define  PREF(f) ((f)&LOCAL)
+#define  PREF2(f1, f2)	 ((PREF(f1) != 0) ? PREF(f1) : PREF(f2))
+#define  COMBINE(f1, f2) (UP((f1)|(f2)) | PREF2(f1, f2))
+	short		id;				/* ID of subre (1..ntree-1) */
+	int			subno;			/* subexpression number (for 'b' and '(') */
+	short		min;			/* min repetitions for iteration or backref */
+	short		max;			/* max repetitions for iteration or backref */
+	struct subre *left;			/* left child, if any (also freelist chain) */
+	struct subre *right;		/* right child, if any */
+	struct state *begin;		/* outarcs from here... */
+	struct state *end;			/* ...ending in inarcs here */
+	struct cnfa cnfa;			/* compacted NFA, if any */
+	struct subre *chain;		/* for bookkeeping and error cleanup */
+};
+
+
+
+/*
+ * table of function pointers for generic manipulation functions
+ * A regex_t's re_fns points to one of these.
+ */
+struct fns
+{
+	void		FUNCPTR(free, (regex_t *));
+};
+
+
+
+/*
+ * the insides of a regex_t, hidden behind a void *
+ */
+struct guts
+{
+	int			magic;
+#define  GUTSMAGIC	 0xfed9
+	int			cflags;			/* copy of compile flags */
+	long		info;			/* copy of re_info */
+	size_t		nsub;			/* copy of re_nsub */
+	struct subre *tree;
+	struct cnfa search;			/* for fast preliminary search */
+	int			ntree;			/* number of subre's, less one */
+	struct colormap cmap;
+	int			FUNCPTR(compare, (const chr *, const chr *, size_t));
+	struct subre *lacons;		/* lookahead-constraint vector */
+	int			nlacons;		/* size of lacons */
+};