diff options
Diffstat (limited to 'generic/regguts.h')
| -rw-r--r-- | generic/regguts.h | 475 |
1 files changed, 242 insertions, 233 deletions
diff --git a/generic/regguts.h b/generic/regguts.h index 36e5092..ad9d5b9 100644 --- a/generic/regguts.h +++ b/generic/regguts.h @@ -2,20 +2,20 @@ * 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. - * + * 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. - * + * + * 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 @@ -28,67 +28,25 @@ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ - - /* - * 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. + * 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. */ -/* standard header files (NULL is a reasonable indicator for them) */ -#ifndef NULL -#include <stdio.h> -#include <stdlib.h> -#include <ctype.h> -#include <limits.h> -#include <string.h> -#endif - /* assertions */ #ifndef assert -# ifndef REG_DEBUG -# define NDEBUG /* no assertions */ -# endif -#include <assert.h> -#endif - -/* voids */ -#ifndef VOID -#define VOID void /* for function return values */ -#endif -#ifndef DISCARD -#define DISCARD VOID /* for throwing values away */ -#endif -#ifndef PVOID -#define PVOID VOID * /* generic pointer */ -#endif -#ifndef VS -#define VS(x) ((PVOID)(x)) /* cast something to generic ptr */ -#endif -#ifndef NOPARMS -#define NOPARMS VOID /* for empty parm lists */ -#endif - -/* const */ -#ifndef CONST -#define CONST const /* for old compilers, might be empty */ -#endif - -/* function-pointer declarator */ -#ifndef FUNCPTR -#if __STDC__ >= 1 -#define FUNCPTR(name, args) (*name)args -#else -#define FUNCPTR(name, args) (*name)() +#ifndef REG_DEBUG +#ifndef NDEBUG +#define NDEBUG /* no assertions */ #endif +#endif /* !REG_DEBUG */ +#include <assert.h> #endif /* memory allocation */ @@ -96,22 +54,17 @@ #define MALLOC(n) malloc(n) #endif #ifndef REALLOC -#define REALLOC(p, n) realloc(VS(p), n) +#define REALLOC(p, n) realloc(p, n) #endif #ifndef FREE -#define FREE(p) free(VS(p)) +#define FREE(p) free(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> */ +#define _POSIX2_RE_DUP_MAX 255 /* normally from <limits.h> */ #endif - - /* * misc */ @@ -120,12 +73,10 @@ #define xxx 1 #define DUPMAX _POSIX2_RE_DUP_MAX -#define INFINITY (DUPMAX+1) +#define DUPINF (DUPMAX+1) #define REMAGIC 0xfed7 /* magic number for main struct */ - - /* * debugging facilities */ @@ -139,8 +90,6 @@ #define MDEBUG(arglist) {} #endif - - /* * bitmap manipulation */ @@ -148,14 +97,13 @@ #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. + * 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 @@ -164,69 +112,74 @@ #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 MAX_COLOR SHRT_MAX /* max color value */ #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. + * 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]; + color ccolor[BYTTAB]; }; struct ptrs { - union tree *pptr[BYTTAB]; + union tree *pptr[BYTTAB]; }; union tree { - struct colors colors; - struct ptrs ptrs; + struct colors colors; + struct ptrs ptrs; }; #define tcolor colors.ccolor #define tptr ptrs.pptr -/* internal per-color structure for the color machinery */ +/* Internal per-color descriptor structure for the color machinery */ struct colordesc { - uchr nchrs; /* number of chars of this color */ - color sub; /* open subcolor (if any); free chain ptr */ -# define NOSUB COLORLESS - struct arc *arcs; /* color chain */ - int flags; -# 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 */ + uchr nchrs; /* number of chars of this color */ + color sub; /* open subcolor (if any); free chain ptr */ +#define NOSUB COLORLESS + struct arc *arcs; /* color chain */ + int flags; +#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 */ +/* + * 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; /* number of colordescs */ - size_t max; /* highest in use */ - color free; /* beginning of free chain (if non-0) */ - struct colordesc *cd; -# define CDEND(cm) (&(cm)->cd[(cm)->max + 1]) -# define NINLINECDS ((size_t)10) - struct colordesc cdspace[NINLINECDS]; - union tree tree[NBYTS]; /* tree top, plus fill blocks */ + int magic; +#define CMMAGIC 0x876 + struct vars *v; /* for compile error reporting */ + size_t ncds; /* number of colordescs */ + size_t max; /* highest in use */ + color free; /* beginning of free chain (if non-0) */ + struct colordesc *cd; +#define CDEND(cm) (&(cm)->cd[(cm)->max + 1]) +#define NINLINECDS ((size_t)10) + struct colordesc cdspace[NINLINECDS]; + union tree tree[NBYTS]; /* tree top, plus fill blocks */ }; /* optimization magic to do fast chr->color mapping */ @@ -245,174 +198,230 @@ struct colormap { #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 locale.c. - * Multi-character collating elements (MCCEs) cause most of the trouble. */ + +/* Representation of a set of characters. */ struct cvec { - int nchrs; /* number of chrs */ - int chrspace; /* number of chrs possible */ - chr *chrs; /* pointer to vector of chrs */ - int nranges; /* number of ranges (chr pairs) */ - int rangespace; /* number of chrs possible */ - chr *ranges; /* pointer to vector of chr pairs */ - int nmcces; /* number of MCCEs */ - int mccespace; /* number of MCCEs possible */ - int nmccechrs; /* number of chrs used for MCCEs */ - chr *mcces[1]; /* pointers to 0-terminated MCCEs */ - /* and both batches of chrs are on the end */ + int nchrs; /* number of chrs */ + int chrspace; /* number of chrs possible */ + chr *chrs; /* pointer to vector of chrs */ + int nranges; /* number of ranges (chr pairs) */ + int rangespace; /* number of chrs possible */ + chr *ranges; /* pointer to vector of chr pairs */ }; -/* caution: this value cannot be changed easily */ -#define MAXMCCE 2 /* length of longest MCCE */ - - - /* - * definitions for NFA internal representation + * definitions for non-deterministic finite autmaton (NFA) internal + * representation * - * Having a "from" pointer within each arc may seem redundant, but it - * saves a lot of hassle. + * Having a "from" pointer within each arc may seem redundant, but it saves a + * lot of hassle. */ + struct state; struct arc { - int type; -# define ARCFREE '\0' - color co; - struct state *from; /* where it's from (and contained within) */ - struct state *to; /* where it's to */ - struct arc *outchain; /* *from's outs chain or free chain */ -# define freechain outchain - struct arc *inchain; /* *to's ins chain */ - struct arc *colorchain; /* color's arc chain */ + 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 */ + struct arc *outchainRev; /* back-link in *from's outs chain */ +#define freechain outchain /* we do not maintain "freechainRev" */ + struct arc *inchain; /* *to's ins chain */ + struct arc *inchainRev; /* back-link in *to's ins chain */ + struct arc *colorchain; /* 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 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 */ + 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 */ - struct vars *v; /* simplifies compile error reporting */ - struct nfa *parent; /* parent NFA, if any */ + 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 */ + 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; /* state number */ + color co; /* COLORLESS is list terminator */ + int to; /* next-state number */ }; struct cnfa { - int nstates; /* number of states */ - int ncolors; /* number of colors */ - 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 */ - struct carc **states; /* vector of pointers to outarc lists */ - struct carc *arcs; /* the area for the lists */ + int nstates; /* number of states */ + int ncolors; /* number of colors */ + 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) - +/* + * This symbol limits the transient heap space used by the regex compiler, + * and thereby also the maximum complexity of NFAs that we'll deal with. + * Currently we only count NFA states and arcs against this; the other + * transient data is generally not large enough to notice compared to those. + * Note that we do not charge anything for the final output data structures + * (the compacted NFA and the colormap). + */ +#ifndef REG_MAX_COMPILE_SPACE +#define REG_MAX_COMPILE_SPACE \ + (100000 * sizeof(struct state) + 100000 * sizeof(struct arcbatch)) +#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; /* '|', '.' (concat), 'b' (backref), '(', '=' */ - 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 retry; /* index into retry memory */ - int subno; /* subexpression number (for 'b' and '(') */ - short min; /* min repetitions, for backref only */ - short max; /* max repetitions, for backref only */ - 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 */ + 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 NOPROP 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)&~NOPROP) | (LMIX(f) & SMIX(f) & MIXED)) +#define MESSY(f) ((f)&(MIXED|CAP|BACKR)) +#define PREF(f) ((f)&NOPROP) +#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. + * 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 *)); + void (*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; - struct colormap cmap; - int FUNCPTR(compare, (CONST chr *, CONST chr *, size_t)); - struct subre *lacons; /* lookahead-constraint vector */ - int nlacons; /* size of lacons */ + 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, plus one */ + struct colormap cmap; + int (*compare) (const chr *, const chr *, size_t); + struct subre *lacons; /* lookahead-constraint vector */ + int nlacons; /* size of lacons */ }; + +/* + * Magic for allocating a variable workspace. This default version is + * stack-hungry. + */ + +#ifndef AllocVars +#define AllocVars(vPtr) \ + struct vars var; \ + register struct vars *vPtr = &var +#endif +#ifndef FreeVars +#define FreeVars(vPtr) ((void) 0) +#endif + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |