| /* |
| * re_*comp and friends - compile REs |
| * This file #includes several others (see the bottom). |
| * |
| * 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. |
| * |
| * $PostgreSQL: pgsql/src/backend/regex/regcomp.c,v 1.46 2008/02/14 17:33:37 tgl Exp $ |
| * |
| */ |
| |
| #include "regex/regguts.h" |
| |
| /* |
| * forward declarations, up here so forward datatypes etc. are defined early |
| */ |
| /* === regcomp.c === */ |
| static void moresubs(struct vars *, int); |
| static int freev(struct vars *, int); |
| static void makesearch(struct vars *, struct nfa *); |
| static struct subre *parse(struct vars *, int, int, struct state *, struct state *); |
| static struct subre *parsebranch(struct vars *, int, int, struct state *, struct state *, int); |
| static void parseqatom(struct vars *, int, int, struct state *, struct state *, struct subre *); |
| static void nonword(struct vars *, int, struct state *, struct state *); |
| static void word(struct vars *, int, struct state *, struct state *); |
| static int scannum(struct vars *); |
| static void repeat(struct vars *, struct state *, struct state *, int, int); |
| static void bracket(struct vars *, struct state *, struct state *); |
| static void cbracket(struct vars *, struct state *, struct state *); |
| static void brackpart(struct vars *, struct state *, struct state *); |
| static const chr *scanplain(struct vars *); |
| static void onechr(struct vars *, chr, struct state *, struct state *); |
| static void dovec(struct vars *, struct cvec *, struct state *, struct state *); |
| static void wordchrs(struct vars *); |
| static struct subre *subre(struct vars *, int, int, struct state *, struct state *); |
| static void freesubre(struct vars *, struct subre *); |
| static void freesrnode(struct vars *, struct subre *); |
| static void optst(struct vars *, struct subre *); |
| static int numst(struct subre *, int); |
| static void markst(struct subre *); |
| static void cleanst(struct vars *); |
| static long nfatree(struct vars *, struct subre *, FILE *); |
| static long nfanode(struct vars *, struct subre *, FILE *); |
| static int newlacon(struct vars *, struct state *, struct state *, int); |
| static void freelacons(struct subre *, int); |
| static void rfree(regex_t *); |
| |
| #ifdef REG_DEBUG |
| static void dump(regex_t *, FILE *); |
| static void dumpst(struct subre *, FILE *, int); |
| static void stdump(struct subre *, FILE *, int); |
| static const char *stid(struct subre *, char *, size_t); |
| #endif |
| /* === regc_lex.c === */ |
| static void lexstart(struct vars *); |
| static void prefixes(struct vars *); |
| static void lexnest(struct vars *, const chr *, const chr *); |
| static void lexword(struct vars *); |
| static int next(struct vars *); |
| static int lexescape(struct vars *); |
| static chr lexdigits(struct vars *, int, int, int); |
| static int brenext(struct vars *, chr); |
| static void skip(struct vars *); |
| static chr newline(void); |
| static chr chrnamed(struct vars *, const chr *, const chr *, chr); |
| |
| /* === regc_color.c === */ |
| static void initcm(struct vars *, struct colormap *); |
| static void freecm(struct colormap *); |
| static void cmtreefree(struct colormap *, union tree *, int); |
| static color setcolor(struct colormap *, chr, pcolor); |
| static color maxcolor(struct colormap *); |
| static color newcolor(struct colormap *); |
| static void freecolor(struct colormap *, pcolor); |
| static color pseudocolor(struct colormap *); |
| static color subcolor(struct colormap *, chr c); |
| static color newsub(struct colormap *, pcolor); |
| static void subrange(struct vars *, chr, chr, struct state *, struct state *); |
| static void subblock(struct vars *, chr, struct state *, struct state *); |
| static void okcolors(struct nfa *, struct colormap *); |
| static void colorchain(struct colormap *, struct arc *); |
| static void uncolorchain(struct colormap *, struct arc *); |
| static void rainbow(struct nfa *, struct colormap *, int, pcolor, struct state *, struct state *); |
| static void colorcomplement(struct nfa *, struct colormap *, int, struct state *, struct state *, struct state *); |
| |
| #ifdef REG_DEBUG |
| static void dumpcolors(struct colormap *, FILE *); |
| static void fillcheck(struct colormap *, union tree *, int, FILE *); |
| static void dumpchr(chr, FILE *); |
| #endif |
| /* === regc_nfa.c === */ |
| static struct nfa *newnfa(struct vars *, struct colormap *, struct nfa *); |
| static void freenfa(struct nfa *); |
| static struct state *newstate(struct nfa *); |
| static struct state *newfstate(struct nfa *, int flag); |
| static void dropstate(struct nfa *, struct state *); |
| static void freestate(struct nfa *, struct state *); |
| static void destroystate(struct nfa *, struct state *); |
| static void newarc(struct nfa *, int, pcolor, struct state *, struct state *); |
| static struct arc *allocarc(struct nfa *, struct state *); |
| static void freearc(struct nfa *, struct arc *); |
| static struct arc *findarc(struct state *, int, pcolor); |
| static void cparc(struct nfa *, struct arc *, struct state *, struct state *); |
| static void moveins(struct nfa *, struct state *, struct state *); |
| static void copyins(struct nfa *, struct state *, struct state *); |
| static void moveouts(struct nfa *, struct state *, struct state *); |
| static void copyouts(struct nfa *, struct state *, struct state *); |
| static void cloneouts(struct nfa *, struct state *, struct state *, struct state *, int); |
| static void delsub(struct nfa *, struct state *, struct state *); |
| static void deltraverse(struct nfa *, struct state *, struct state *); |
| static void dupnfa(struct nfa *, struct state *, struct state *, struct state *, struct state *); |
| static void duptraverse(struct nfa *, struct state *, struct state *); |
| static void cleartraverse(struct nfa *, struct state *); |
| static void specialcolors(struct nfa *); |
| static long optimize(struct nfa *, FILE *); |
| static void pullback(struct nfa *, FILE *); |
| static int pull(struct nfa *, struct arc *); |
| static void pushfwd(struct nfa *, FILE *); |
| static int push(struct nfa *, struct arc *); |
| |
| #define INCOMPATIBLE 1 /* destroys arc */ |
| #define SATISFIED 2 /* constraint satisfied */ |
| #define COMPATIBLE 3 /* compatible but not satisfied yet */ |
| static int combine(struct arc *, struct arc *); |
| static void fixempties(struct nfa *, FILE *); |
| static int unempty(struct nfa *, struct arc *); |
| static void cleanup(struct nfa *); |
| static void markreachable(struct nfa *, struct state *, struct state *, struct state *); |
| static void markcanreach(struct nfa *, struct state *, struct state *, struct state *); |
| static long analyze(struct nfa *); |
| static void compact(struct nfa *, struct cnfa *); |
| static void carcsort(struct carc *, struct carc *); |
| static void freecnfa(struct cnfa *); |
| static void dumpnfa(struct nfa *, FILE *); |
| |
| #ifdef REG_DEBUG |
| static void dumpstate(struct state *, FILE *); |
| static void dumparcs(struct state *, FILE *); |
| static int dumprarcs(struct arc *, struct state *, FILE *, int); |
| static void dumparc(struct arc *, struct state *, FILE *); |
| static void dumpcnfa(struct cnfa *, FILE *); |
| static void dumpcstate(int, struct carc *, struct cnfa *, FILE *); |
| #endif |
| /* === regc_cvec.c === */ |
| static struct cvec *newcvec(int, int); |
| static struct cvec *clearcvec(struct cvec *); |
| static void addchr(struct cvec *, chr); |
| static void addrange(struct cvec *, chr, chr); |
| static struct cvec *getcvec(struct vars *, int, int); |
| static void freecvec(struct cvec *); |
| |
| /* === regc_locale.c === */ |
| static int pg_wc_isdigit(pg_wchar c); |
| static int pg_wc_isalpha(pg_wchar c); |
| static int pg_wc_isalnum(pg_wchar c); |
| static int pg_wc_isupper(pg_wchar c); |
| static int pg_wc_islower(pg_wchar c); |
| static int pg_wc_isgraph(pg_wchar c); |
| static int pg_wc_isprint(pg_wchar c); |
| static int pg_wc_ispunct(pg_wchar c); |
| static int pg_wc_isspace(pg_wchar c); |
| static pg_wchar pg_wc_toupper(pg_wchar c); |
| static pg_wchar pg_wc_tolower(pg_wchar c); |
| static celt element(struct vars *, const chr *, const chr *); |
| static struct cvec *range(struct vars *, celt, celt, int); |
| static int before(celt, celt); |
| static struct cvec *eclass(struct vars *, celt, int); |
| static struct cvec *cclass(struct vars *, const chr *, const chr *, int); |
| static struct cvec *allcases(struct vars *, chr); |
| static int cmp(const chr *, const chr *, size_t); |
| static int casecmp(const chr *, const chr *, size_t); |
| |
| |
| /* internal variables, bundled for easy passing around */ |
| struct vars |
| { |
| regex_t *re; |
| const chr *now; /* scan pointer into string */ |
| const chr *stop; /* end of string */ |
| const chr *savenow; /* saved now and stop for "subroutine call" */ |
| const chr *savestop; |
| int err; /* error code (0 if none) */ |
| int cflags; /* copy of compile flags */ |
| int lasttype; /* type of previous token */ |
| int nexttype; /* type of next token */ |
| chr nextvalue; /* value (if any) of next token */ |
| int lexcon; /* lexical context type (see lex.c) */ |
| int nsubexp; /* subexpression count */ |
| struct subre **subs; /* subRE pointer vector */ |
| size_t nsubs; /* length of vector */ |
| struct subre *sub10[10]; /* initial vector, enough for most */ |
| struct nfa *nfa; /* the NFA */ |
| struct colormap *cm; /* character color map */ |
| color nlcolor; /* color of newline */ |
| struct state *wordchrs; /* state in nfa holding word-char outarcs */ |
| struct subre *tree; /* subexpression tree */ |
| struct subre *treechain; /* all tree nodes allocated */ |
| struct subre *treefree; /* any free tree nodes */ |
| int ntree; /* number of tree nodes */ |
| struct cvec *cv; /* interface cvec */ |
| struct cvec *cv2; /* utility cvec */ |
| struct subre *lacons; /* lookahead-constraint vector */ |
| int nlacons; /* size of lacons */ |
| }; |
| |
| /* parsing macros; most know that `v' is the struct vars pointer */ |
| #define NEXT() (next(v)) /* advance by one token */ |
| #define SEE(t) (v->nexttype == (t)) /* is next token this? */ |
| #define EAT(t) (SEE(t) && next(v)) /* if next is this, swallow it */ |
| #define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */ |
| #define ISERR() VISERR(v) |
| #define VERR(vv,e) ((vv)->nexttype = EOS, ((vv)->err) ? (vv)->err :\ |
| ((vv)->err = (e))) |
| #undef ERR |
| #define ERR(e) VERR(v, e) /* record an error */ |
| #define NOERR() {if (ISERR()) return;} /* if error seen, return */ |
| #define NOERRN() {if (ISERR()) return NULL;} /* NOERR with retval */ |
| #define NOERRZ() {if (ISERR()) return 0;} /* NOERR with retval */ |
| #define INSIST(c, e) ((c) ? 0 : ERR(e)) /* if condition false, error */ |
| #define NOTE(b) (v->re->re_info |= (b)) /* note visible condition */ |
| #define EMPTYARC(x, y) newarc(v->nfa, EMPTY, 0, x, y) |
| |
| /* token type codes, some also used as NFA arc types */ |
| #define EMPTY 'n' /* no token present */ |
| #define EOS 'e' /* end of string */ |
| #define PLAIN 'p' /* ordinary character */ |
| #define DIGIT 'd' /* digit (in bound) */ |
| #define BACKREF 'b' /* back reference */ |
| #define COLLEL 'I' /* start of [. */ |
| #define ECLASS 'E' /* start of [= */ |
| #define CCLASS 'C' /* start of [: */ |
| #define END 'X' /* end of [. [= [: */ |
| #define RANGE 'R' /* - within [] which might be range delim. */ |
| #define LACON 'L' /* lookahead constraint subRE */ |
| #define AHEAD 'a' /* color-lookahead arc */ |
| #define BEHIND 'r' /* color-lookbehind arc */ |
| #define WBDRY 'w' /* word boundary constraint */ |
| #define NWBDRY 'W' /* non-word-boundary constraint */ |
| #define SBEGIN 'A' /* beginning of string (even if not BOL) */ |
| #define SEND 'Z' /* end of string (even if not EOL) */ |
| #define PREFER 'P' /* length preference */ |
| |
| /* is an arc colored, and hence on a color chain? */ |
| #define COLORED(a) \ |
| ((a)->type == PLAIN || (a)->type == AHEAD || (a)->type == BEHIND) |
| |
| |
| /* static function list */ |
| static struct fns functions = { |
| rfree, /* regfree insides */ |
| }; |
| |
| |
| |
| /* |
| * pg_regcomp - compile regular expression |
| */ |
| int |
| pg_regcomp(regex_t *re, |
| const chr *string, |
| size_t len, |
| int flags) |
| { |
| struct vars var; |
| struct vars *v = &var; |
| struct guts *g; |
| int i; |
| size_t j; |
| |
| #ifdef REG_DEBUG |
| FILE *debug = (flags & REG_PROGRESS) ? stdout : (FILE *) NULL; |
| #else |
| FILE *debug = (FILE *) NULL; |
| #endif |
| |
| #define CNOERR() { if (ISERR()) return freev(v, v->err); } |
| |
| /* sanity checks */ |
| |
| if (re == NULL || string == NULL) |
| return REG_INVARG; |
| if ((flags & REG_QUOTE) && |
| (flags & (REG_ADVANCED | REG_EXPANDED | REG_NEWLINE))) |
| return REG_INVARG; |
| if (!(flags & REG_EXTENDED) && (flags & REG_ADVF)) |
| return REG_INVARG; |
| |
| /* initial setup (after which freev() is callable) */ |
| v->re = re; |
| v->now = string; |
| v->stop = v->now + len; |
| v->savenow = v->savestop = NULL; |
| v->err = 0; |
| v->cflags = flags; |
| v->nsubexp = 0; |
| v->subs = v->sub10; |
| v->nsubs = 10; |
| for (j = 0; j < v->nsubs; j++) |
| v->subs[j] = NULL; |
| v->nfa = NULL; |
| v->cm = NULL; |
| v->nlcolor = COLORLESS; |
| v->wordchrs = NULL; |
| v->tree = NULL; |
| v->treechain = NULL; |
| v->treefree = NULL; |
| v->cv = NULL; |
| v->cv2 = NULL; |
| v->lacons = NULL; |
| v->nlacons = 0; |
| re->re_magic = REMAGIC; |
| re->re_info = 0; /* bits get set during parse */ |
| re->re_csize = sizeof(chr); |
| re->re_guts = NULL; |
| re->re_fns = VS(&functions); |
| |
| /* more complex setup, malloced things */ |
| re->re_guts = VS(MALLOC(sizeof(struct guts))); |
| if (re->re_guts == NULL) |
| return freev(v, REG_ESPACE); |
| g = (struct guts *) re->re_guts; |
| g->tree = NULL; |
| initcm(v, &g->cmap); |
| v->cm = &g->cmap; |
| g->lacons = NULL; |
| g->nlacons = 0; |
| ZAPCNFA(g->search); |
| v->nfa = newnfa(v, v->cm, (struct nfa *) NULL); |
| CNOERR(); |
| v->cv = newcvec(100, 20); |
| if (v->cv == NULL) |
| return freev(v, REG_ESPACE); |
| |
| /* parsing */ |
| lexstart(v); /* also handles prefixes */ |
| if ((v->cflags & REG_NLSTOP) || (v->cflags & REG_NLANCH)) |
| { |
| /* assign newline a unique color */ |
| v->nlcolor = subcolor(v->cm, newline()); |
| okcolors(v->nfa, v->cm); |
| } |
| CNOERR(); |
| v->tree = parse(v, EOS, PLAIN, v->nfa->init, v->nfa->final); |
| assert(SEE(EOS)); /* even if error; ISERR() => SEE(EOS) */ |
| CNOERR(); |
| assert(v->tree != NULL); |
| |
| /* finish setup of nfa and its subre tree */ |
| specialcolors(v->nfa); |
| CNOERR(); |
| #ifdef REG_DEBUG |
| if (debug != NULL) |
| { |
| fprintf(debug, "\n\n\n========= RAW ==========\n"); |
| dumpnfa(v->nfa, debug); |
| dumpst(v->tree, debug, 1); |
| } |
| #endif |
| optst(v, v->tree); |
| v->ntree = numst(v->tree, 1); |
| markst(v->tree); |
| cleanst(v); |
| #ifdef REG_DEBUG |
| if (debug != NULL) |
| { |
| fprintf(debug, "\n\n\n========= TREE FIXED ==========\n"); |
| dumpst(v->tree, debug, 1); |
| } |
| #endif |
| |
| /* build compacted NFAs for tree and lacons */ |
| re->re_info |= nfatree(v, v->tree, debug); |
| CNOERR(); |
| assert(v->nlacons == 0 || v->lacons != NULL); |
| for (i = 1; i < v->nlacons; i++) |
| { |
| #ifdef REG_DEBUG |
| if (debug != NULL) |
| fprintf(debug, "\n\n\n========= LA%d ==========\n", i); |
| #endif |
| nfanode(v, &v->lacons[i], debug); |
| } |
| CNOERR(); |
| if (v->tree->flags & SHORTER) |
| NOTE(REG_USHORTEST); |
| |
| /* build compacted NFAs for tree, lacons, fast search */ |
| #ifdef REG_DEBUG |
| if (debug != NULL) |
| fprintf(debug, "\n\n\n========= SEARCH ==========\n"); |
| #endif |
| /* can sacrifice main NFA now, so use it as work area */ |
| (DISCARD) optimize(v->nfa, debug); |
| CNOERR(); |
| makesearch(v, v->nfa); |
| CNOERR(); |
| compact(v->nfa, &g->search); |
| CNOERR(); |
| |
| /* looks okay, package it up */ |
| re->re_nsub = v->nsubexp; |
| v->re = NULL; /* freev no longer frees re */ |
| g->magic = GUTSMAGIC; |
| g->cflags = v->cflags; |
| g->info = re->re_info; |
| g->nsub = re->re_nsub; |
| g->tree = v->tree; |
| v->tree = NULL; |
| g->ntree = v->ntree; |
| g->compare = (v->cflags & REG_ICASE) ? casecmp : cmp; |
| g->lacons = v->lacons; |
| v->lacons = NULL; |
| g->nlacons = v->nlacons; |
| |
| #ifdef REG_DEBUG |
| if (flags & REG_DUMP) |
| dump(re, stdout); |
| #endif |
| |
| assert(v->err == 0); |
| return freev(v, 0); |
| } |
| |
| /* |
| * moresubs - enlarge subRE vector |
| */ |
| static void |
| moresubs(struct vars * v, |
| int wanted) /* want enough room for this one */ |
| { |
| struct subre **p; |
| size_t n; |
| |
| assert(wanted > 0 && (size_t) wanted >= v->nsubs); |
| n = (size_t) wanted *3 / 2 + 1; |
| |
| if (v->subs == v->sub10) |
| { |
| p = (struct subre **) MALLOC(n * sizeof(struct subre *)); |
| if (p != NULL) |
| memcpy(VS(p), VS(v->subs), |
| v->nsubs * sizeof(struct subre *)); |
| } |
| else |
| p = (struct subre **) REALLOC(v->subs, n * sizeof(struct subre *)); |
| if (p == NULL) |
| { |
| ERR(REG_ESPACE); |
| return; |
| } |
| v->subs = p; |
| for (p = &v->subs[v->nsubs]; v->nsubs < n; p++, v->nsubs++) |
| *p = NULL; |
| assert(v->nsubs == n); |
| assert((size_t) wanted < v->nsubs); |
| } |
| |
| /* |
| * freev - free vars struct's substructures where necessary |
| * |
| * Optionally does error-number setting, and always returns error code |
| * (if any), to make error-handling code terser. |
| */ |
| static int |
| freev(struct vars * v, |
| int err) |
| { |
| if (v->re != NULL) |
| rfree(v->re); |
| if (v->subs != v->sub10) |
| FREE(v->subs); |
| if (v->nfa != NULL) |
| freenfa(v->nfa); |
| if (v->tree != NULL) |
| freesubre(v, v->tree); |
| if (v->treechain != NULL) |
| cleanst(v); |
| if (v->cv != NULL) |
| freecvec(v->cv); |
| if (v->cv2 != NULL) |
| freecvec(v->cv2); |
| if (v->lacons != NULL) |
| freelacons(v->lacons, v->nlacons); |
| ERR(err); /* nop if err==0 */ |
| |
| return v->err; |
| } |
| |
| /* |
| * makesearch - turn an NFA into a search NFA (implicit prepend of .*?) |
| * NFA must have been optimize()d already. |
| */ |
| static void |
| makesearch(struct vars * v, |
| struct nfa * nfa) |
| { |
| struct arc *a; |
| struct arc *b; |
| struct state *pre = nfa->pre; |
| struct state *s; |
| struct state *s2; |
| struct state *slist; |
| |
| /* no loops are needed if it's anchored */ |
| for (a = pre->outs; a != NULL; a = a->outchain) |
| { |
| assert(a->type == PLAIN); |
| if (a->co != nfa->bos[0] && a->co != nfa->bos[1]) |
| break; |
| } |
| if (a != NULL) |
| { |
| /* add implicit .* in front */ |
| rainbow(nfa, v->cm, PLAIN, COLORLESS, pre, pre); |
| |
| /* and ^* and \A* too -- not always necessary, but harmless */ |
| newarc(nfa, PLAIN, nfa->bos[0], pre, pre); |
| newarc(nfa, PLAIN, nfa->bos[1], pre, pre); |
| } |
| |
| /* |
| * Now here's the subtle part. Because many REs have no lookback |
| * constraints, often knowing when you were in the pre state tells you |
| * little; it's the next state(s) that are informative. But some of them |
| * may have other inarcs, i.e. it may be possible to make actual progress |
| * and then return to one of them. We must de-optimize such cases, |
| * splitting each such state into progress and no-progress states. |
| */ |
| |
| /* first, make a list of the states */ |
| slist = NULL; |
| for (a = pre->outs; a != NULL; a = a->outchain) |
| { |
| s = a->to; |
| for (b = s->ins; b != NULL; b = b->inchain) |
| if (b->from != pre) |
| break; |
| if (b != NULL && s->tmp == NULL) |
| { |
| /* |
| * Must be split if not already in the list (fixes bugs 505048, |
| * 230589, 840258, 504785). |
| */ |
| s->tmp = slist; |
| slist = s; |
| } |
| } |
| |
| /* do the splits */ |
| for (s = slist; s != NULL; s = s2) |
| { |
| s2 = newstate(nfa); |
| copyouts(nfa, s, s2); |
| for (a = s->ins; a != NULL; a = b) |
| { |
| b = a->inchain; |
| if (a->from != pre) |
| { |
| cparc(nfa, a, a->from, s2); |
| freearc(nfa, a); |
| } |
| } |
| s2 = s->tmp; |
| s->tmp = NULL; /* clean up while we're at it */ |
| } |
| } |
| |
| /* |
| * parse - parse an RE |
| * |
| * This is actually just the top level, which parses a bunch of branches |
| * tied together with '|'. They appear in the tree as the left children |
| * of a chain of '|' subres. |
| */ |
| static struct subre * |
| parse(struct vars * v, |
| int stopper, /* EOS or ')' */ |
| int type, /* LACON (lookahead subRE) or PLAIN */ |
| struct state * init, /* initial state */ |
| struct state * final) /* final state */ |
| { |
| struct state *left; /* scaffolding for branch */ |
| struct state *right; |
| struct subre *branches; /* top level */ |
| struct subre *branch; /* current branch */ |
| struct subre *t; /* temporary */ |
| int firstbranch; /* is this the first branch? */ |
| |
| assert(stopper == ')' || stopper == EOS); |
| |
| branches = subre(v, '|', LONGER, init, final); |
| NOERRN(); |
| branch = branches; |
| firstbranch = 1; |
| do |
| { /* a branch */ |
| if (!firstbranch) |
| { |
| /* need a place to hang it */ |
| branch->right = subre(v, '|', LONGER, init, final); |
| NOERRN(); |
| branch = branch->right; |
| } |
| firstbranch = 0; |
| left = newstate(v->nfa); |
| right = newstate(v->nfa); |
| NOERRN(); |
| EMPTYARC(init, left); |
| EMPTYARC(right, final); |
| NOERRN(); |
| branch->left = parsebranch(v, stopper, type, left, right, 0); |
| NOERRN(); |
| branch->flags |= UP(branch->flags | branch->left->flags); |
| if ((branch->flags & ~branches->flags) != 0) /* new flags */ |
| for (t = branches; t != branch; t = t->right) |
| t->flags |= branch->flags; |
| } while (EAT('|')); |
| assert(SEE(stopper) || SEE(EOS)); |
| |
| if (!SEE(stopper)) |
| { |
| assert(stopper == ')' && SEE(EOS)); |
| ERR(REG_EPAREN); |
| } |
| |
| /* optimize out simple cases */ |
| if (branch == branches) |
| { /* only one branch */ |
| assert(branch->right == NULL); |
| t = branch->left; |
| branch->left = NULL; |
| freesubre(v, branches); |
| branches = t; |
| } |
| else if (!MESSY(branches->flags)) |
| { /* no interesting innards */ |
| freesubre(v, branches->left); |
| branches->left = NULL; |
| freesubre(v, branches->right); |
| branches->right = NULL; |
| branches->op = '='; |
| } |
| |
| return branches; |
| } |
| |
| /* |
| * parsebranch - parse one branch of an RE |
| * |
| * This mostly manages concatenation, working closely with parseqatom(). |
| * Concatenated things are bundled up as much as possible, with separate |
| * ',' nodes introduced only when necessary due to substructure. |
| */ |
| static struct subre * |
| parsebranch(struct vars * v, |
| int stopper, /* EOS or ')' */ |
| int type, /* LACON (lookahead subRE) or PLAIN */ |
| struct state * left, /* leftmost state */ |
| struct state * right, /* rightmost state */ |
| int partial) /* is this only part of a branch? */ |
| { |
| struct state *lp; /* left end of current construct */ |
| int seencontent; /* is there anything in this branch yet? */ |
| struct subre *t; |
| |
| lp = left; |
| seencontent = 0; |
| t = subre(v, '=', 0, left, right); /* op '=' is tentative */ |
| NOERRN(); |
| while (!SEE('|') && !SEE(stopper) && !SEE(EOS)) |
| { |
| if (seencontent) |
| { /* implicit concat operator */ |
| lp = newstate(v->nfa); |
| NOERRN(); |
| moveins(v->nfa, right, lp); |
| } |
| seencontent = 1; |
| |
| /* NB, recursion in parseqatom() may swallow rest of branch */ |
| parseqatom(v, stopper, type, lp, right, t); |
| } |
| |
| if (!seencontent) |
| { /* empty branch */ |
| if (!partial) |
| NOTE(REG_UUNSPEC); |
| assert(lp == left); |
| EMPTYARC(left, right); |
| } |
| |
| return t; |
| } |
| |
| /* |
| * parseqatom - parse one quantified atom or constraint of an RE |
| * |
| * The bookkeeping near the end cooperates very closely with parsebranch(); |
| * in particular, it contains a recursion that can involve parsing the rest |
| * of the branch, making this function's name somewhat inaccurate. |
| */ |
| static void |
| parseqatom(struct vars * v, |
| int stopper, /* EOS or ')' */ |
| int type, /* LACON (lookahead subRE) or PLAIN */ |
| struct state * lp, /* left state to hang it on */ |
| struct state * rp, /* right state to hang it on */ |
| struct subre * top) /* subtree top */ |
| { |
| struct state *s; /* temporaries for new states */ |
| struct state *s2; |
| |
| #define ARCV(t, val) newarc(v->nfa, t, val, lp, rp) |
| int m, |
| n; |
| struct subre *atom; /* atom's subtree */ |
| struct subre *t; |
| int cap; /* capturing parens? */ |
| int pos; /* positive lookahead? */ |
| int subno; /* capturing-parens or backref number */ |
| int atomtype; |
| int qprefer; /* quantifier short/long preference */ |
| int f; |
| struct subre **atomp; /* where the pointer to atom is */ |
| |
| /* initial bookkeeping */ |
| atom = NULL; |
| assert(lp->nouts == 0); /* must string new code */ |
| assert(rp->nins == 0); /* between lp and rp */ |
| subno = 0; /* just to shut lint up */ |
| |
| /* an atom or constraint... */ |
| atomtype = v->nexttype; |
| switch (atomtype) |
| { |
| /* first, constraints, which end by returning */ |
| case '^': |
| ARCV('^', 1); |
| if (v->cflags & REG_NLANCH) |
| ARCV(BEHIND, v->nlcolor); |
| NEXT(); |
| return; |
| break; |
| case '$': |
| ARCV('$', 1); |
| if (v->cflags & REG_NLANCH) |
| ARCV(AHEAD, v->nlcolor); |
| NEXT(); |
| return; |
| break; |
| case SBEGIN: |
| ARCV('^', 1); /* BOL */ |
| ARCV('^', 0); /* or BOS */ |
| NEXT(); |
| return; |
| break; |
| case SEND: |
| ARCV('$', 1); /* EOL */ |
| ARCV('$', 0); /* or EOS */ |
| NEXT(); |
| return; |
| break; |
| case '<': |
| wordchrs(v); /* does NEXT() */ |
| s = newstate(v->nfa); |
| NOERR(); |
| nonword(v, BEHIND, lp, s); |
| word(v, AHEAD, s, rp); |
| return; |
| break; |
| case '>': |
| wordchrs(v); /* does NEXT() */ |
| s = newstate(v->nfa); |
| NOERR(); |
| word(v, BEHIND, lp, s); |
| nonword(v, AHEAD, s, rp); |
| return; |
| break; |
| case WBDRY: |
| wordchrs(v); /* does NEXT() */ |
| s = newstate(v->nfa); |
| NOERR(); |
| nonword(v, BEHIND, lp, s); |
| word(v, AHEAD, s, rp); |
| s = newstate(v->nfa); |
| NOERR(); |
| word(v, BEHIND, lp, s); |
| nonword(v, AHEAD, s, rp); |
| return; |
| break; |
| case NWBDRY: |
| wordchrs(v); /* does NEXT() */ |
| s = newstate(v->nfa); |
| NOERR(); |
| word(v, BEHIND, lp, s); |
| word(v, AHEAD, s, rp); |
| s = newstate(v->nfa); |
| NOERR(); |
| nonword(v, BEHIND, lp, s); |
| nonword(v, AHEAD, s, rp); |
| return; |
| break; |
| case LACON: /* lookahead constraint */ |
| pos = v->nextvalue; |
| NEXT(); |
| s = newstate(v->nfa); |
| s2 = newstate(v->nfa); |
| NOERR(); |
| t = parse(v, ')', LACON, s, s2); |
| freesubre(v, t); /* internal structure irrelevant */ |
| assert(SEE(')') || ISERR()); |
| NEXT(); |
| n = newlacon(v, s, s2, pos); |
| NOERR(); |
| ARCV(LACON, n); |
| return; |
| break; |
| /* then errors, to get them out of the way */ |
| case '*': |
| case '+': |
| case '?': |
| case '{': |
| ERR(REG_BADRPT); |
| return; |
| break; |
| default: |
| ERR(REG_ASSERT); |
| return; |
| break; |
| /* then plain characters, and minor variants on that theme */ |
| case ')': /* unbalanced paren */ |
| if ((v->cflags & REG_ADVANCED) != REG_EXTENDED) |
| { |
| ERR(REG_EPAREN); |
| return; |
| } |
| /* legal in EREs due to specification botch */ |
| NOTE(REG_UPBOTCH); |
| /* fallthrough into case PLAIN */ |
| case PLAIN: |
| onechr(v, v->nextvalue, lp, rp); |
| okcolors(v->nfa, v->cm); |
| NOERR(); |
| NEXT(); |
| break; |
| case '[': |
| if (v->nextvalue == 1) |
| bracket(v, lp, rp); |
| else |
| cbracket(v, lp, rp); |
| assert(SEE(']') || ISERR()); |
| NEXT(); |
| break; |
| case '.': |
| rainbow(v->nfa, v->cm, PLAIN, |
| (v->cflags & REG_NLSTOP) ? v->nlcolor : COLORLESS, |
| lp, rp); |
| NEXT(); |
| break; |
| /* and finally the ugly stuff */ |
| case '(': /* value flags as capturing or non */ |
| cap = (type == LACON) ? 0 : v->nextvalue; |
| if (cap) |
| { |
| v->nsubexp++; |
| subno = v->nsubexp; |
| if ((size_t) subno >= v->nsubs) |
| moresubs(v, subno); |
| assert((size_t) subno < v->nsubs); |
| } |
| else |
| atomtype = PLAIN; /* something that's not '(' */ |
| NEXT(); |
| /* need new endpoints because tree will contain pointers */ |
| s = newstate(v->nfa); |
| s2 = newstate(v->nfa); |
| NOERR(); |
| EMPTYARC(lp, s); |
| EMPTYARC(s2, rp); |
| NOERR(); |
| atom = parse(v, ')', PLAIN, s, s2); |
| assert(SEE(')') || ISERR()); |
| NEXT(); |
| NOERR(); |
| if (cap) |
| { |
| v->subs[subno] = atom; |
| t = subre(v, '(', atom->flags | CAP, lp, rp); |
| NOERR(); |
| t->subno = subno; |
| t->left = atom; |
| atom = t; |
| } |
| /* postpone everything else pending possible {0} */ |
| break; |
| case BACKREF: /* the Feature From The Black Lagoon */ |
| INSIST(type != LACON, REG_ESUBREG); |
| INSIST(v->nextvalue < v->nsubs, REG_ESUBREG); |
| INSIST(v->subs[v->nextvalue] != NULL, REG_ESUBREG); |
| NOERR(); |
| assert(v->nextvalue > 0); |
| atom = subre(v, 'b', BACKR, lp, rp); |
| subno = v->nextvalue; |
| atom->subno = subno; |
| EMPTYARC(lp, rp); /* temporarily, so there's something */ |
| NEXT(); |
| break; |
| } |
| |
| /* ...and an atom may be followed by a quantifier */ |
| switch (v->nexttype) |
| { |
| case '*': |
| m = 0; |
| n = INFINITY; |
| qprefer = (v->nextvalue) ? LONGER : SHORTER; |
| NEXT(); |
| break; |
| case '+': |
| m = 1; |
| n = INFINITY; |
| qprefer = (v->nextvalue) ? LONGER : SHORTER; |
| NEXT(); |
| break; |
| case '?': |
| m = 0; |
| n = 1; |
| qprefer = (v->nextvalue) ? LONGER : SHORTER; |
| NEXT(); |
| break; |
| case '{': |
| NEXT(); |
| m = scannum(v); |
| if (EAT(',')) |
| { |
| if (SEE(DIGIT)) |
| n = scannum(v); |
| else |
| n = INFINITY; |
| if (m > n) |
| { |
| ERR(REG_BADBR); |
| return; |
| } |
| /* {m,n} exercises preference, even if it's {m,m} */ |
| qprefer = (v->nextvalue) ? LONGER : SHORTER; |
| } |
| else |
| { |
| n = m; |
| /* {m} passes operand's preference through */ |
| qprefer = 0; |
| } |
| if (!SEE('}')) |
| { /* catches errors too */ |
| ERR(REG_BADBR); |
| return; |
| } |
| NEXT(); |
| break; |
| default: /* no quantifier */ |
| m = n = 1; |
| qprefer = 0; |
| break; |
| } |
| |
| /* annoying special case: {0} or {0,0} cancels everything */ |
| if (m == 0 && n == 0) |
| { |
| if (atom != NULL) |
| freesubre(v, atom); |
| if (atomtype == '(') |
| v->subs[subno] = NULL; |
| delsub(v->nfa, lp, rp); |
| EMPTYARC(lp, rp); |
| return; |
| } |
| |
| /* if not a messy case, avoid hard part */ |
| assert(!MESSY(top->flags)); |
| f = top->flags | qprefer | ((atom != NULL) ? atom->flags : 0); |
| if (atomtype != '(' && atomtype != BACKREF && !MESSY(UP(f))) |
| { |
| if (!(m == 1 && n == 1)) |
| repeat(v, lp, rp, m, n); |
| if (atom != NULL) |
| freesubre(v, atom); |
| top->flags = f; |
| return; |
| } |
| |
| /* |
| * hard part: something messy That is, capturing parens, back reference, |
| * short/long clash, or an atom with substructure containing one of those. |
| */ |
| |
| /* now we'll need a subre for the contents even if they're boring */ |
| if (atom == NULL) |
| { |
| atom = subre(v, '=', 0, lp, rp); |
| NOERR(); |
| } |
| |
| /* |
| * prepare a general-purpose state skeleton |
| * |
| * ---> [s] ---prefix---> [begin] ---atom---> [end] ----rest---> [rp] / / |
| * [lp] ----> [s2] ----bypass--------------------- |
| * |
| * where bypass is an empty, and prefix is some repetitions of atom |
| */ |
| s = newstate(v->nfa); /* first, new endpoints for the atom */ |
| s2 = newstate(v->nfa); |
| NOERR(); |
| moveouts(v->nfa, lp, s); |
| moveins(v->nfa, rp, s2); |
| NOERR(); |
| atom->begin = s; |
| atom->end = s2; |
| s = newstate(v->nfa); /* and spots for prefix and bypass */ |
| s2 = newstate(v->nfa); |
| NOERR(); |
| EMPTYARC(lp, s); |
| EMPTYARC(lp, s2); |
| NOERR(); |
| |
| /* break remaining subRE into x{...} and what follows */ |
| t = subre(v, '.', COMBINE(qprefer, atom->flags), lp, rp); |
| t->left = atom; |
| atomp = &t->left; |
| /* here we should recurse... but we must postpone that to the end */ |
| |
| /* split top into prefix and remaining */ |
| assert(top->op == '=' && top->left == NULL && top->right == NULL); |
| top->left = subre(v, '=', top->flags, top->begin, lp); |
| top->op = '.'; |
| top->right = t; |
| |
| /* if it's a backref, now is the time to replicate the subNFA */ |
| if (atomtype == BACKREF) |
| { |
| assert(atom->begin->nouts == 1); /* just the EMPTY */ |
| delsub(v->nfa, atom->begin, atom->end); |
| assert(v->subs[subno] != NULL); |
| /* and here's why the recursion got postponed: it must */ |
| /* wait until the skeleton is filled in, because it may */ |
| /* hit a backref that wants to copy the filled-in skeleton */ |
| dupnfa(v->nfa, v->subs[subno]->begin, v->subs[subno]->end, |
| atom->begin, atom->end); |
| NOERR(); |
| } |
| |
| /* it's quantifier time; first, turn x{0,...} into x{1,...}|empty */ |
| if (m == 0) |
| { |
| EMPTYARC(s2, atom->end); /* the bypass */ |
| assert(PREF(qprefer) != 0); |
| f = COMBINE(qprefer, atom->flags); |
| t = subre(v, '|', f, lp, atom->end); |
| NOERR(); |
| t->left = atom; |
| t->right = subre(v, '|', PREF(f), s2, atom->end); |
| NOERR(); |
| t->right->left = subre(v, '=', 0, s2, atom->end); |
| NOERR(); |
| *atomp = t; |
| atomp = &t->left; |
| m = 1; |
| } |
| |
| /* deal with the rest of the quantifier */ |
| if (atomtype == BACKREF) |
| { |
| /* special case: backrefs have internal quantifiers */ |
| EMPTYARC(s, atom->begin); /* empty prefix */ |
| /* just stuff everything into atom */ |
| repeat(v, atom->begin, atom->end, m, n); |
| atom->min = (short) m; |
| atom->max = (short) n; |
| atom->flags |= COMBINE(qprefer, atom->flags); |
| } |
| else if (m == 1 && n == 1) |
| { |
| /* no/vacuous quantifier: done */ |
| EMPTYARC(s, atom->begin); /* empty prefix */ |
| } |
| else |
| { |
| /* turn x{m,n} into x{m-1,n-1}x, with capturing */ |
| /* parens in only second x */ |
| dupnfa(v->nfa, atom->begin, atom->end, s, atom->begin); |
| assert(m >= 1 && m != INFINITY && n >= 1); |
| repeat(v, s, atom->begin, m - 1, (n == INFINITY) ? n : n - 1); |
| f = COMBINE(qprefer, atom->flags); |
| t = subre(v, '.', f, s, atom->end); /* prefix and atom */ |
| NOERR(); |
| t->left = subre(v, '=', PREF(f), s, atom->begin); |
| NOERR(); |
| t->right = atom; |
| *atomp = t; |
| } |
| |
| /* and finally, look after that postponed recursion */ |
| t = top->right; |
| if (!(SEE('|') || SEE(stopper) || SEE(EOS))) |
| t->right = parsebranch(v, stopper, type, atom->end, rp, 1); |
| else |
| { |
| EMPTYARC(atom->end, rp); |
| t->right = subre(v, '=', 0, atom->end, rp); |
| } |
| assert(SEE('|') || SEE(stopper) || SEE(EOS)); |
| t->flags |= COMBINE(t->flags, t->right->flags); |
| top->flags |= COMBINE(top->flags, t->flags); |
| } |
| |
| /* |
| * nonword - generate arcs for non-word-character ahead or behind |
| */ |
| static void |
| nonword(struct vars * v, |
| int dir, /* AHEAD or BEHIND */ |
| struct state * lp, |
| struct state * rp) |
| { |
| int anchor = (dir == AHEAD) ? '$' : '^'; |
| |
| assert(dir == AHEAD || dir == BEHIND); |
| newarc(v->nfa, anchor, 1, lp, rp); |
| newarc(v->nfa, anchor, 0, lp, rp); |
| colorcomplement(v->nfa, v->cm, dir, v->wordchrs, lp, rp); |
| /* (no need for special attention to \n) */ |
| } |
| |
| /* |
| * word - generate arcs for word character ahead or behind |
| */ |
| static void |
| word(struct vars * v, |
| int dir, /* AHEAD or BEHIND */ |
| struct state * lp, |
| struct state * rp) |
| { |
| assert(dir == AHEAD || dir == BEHIND); |
| cloneouts(v->nfa, v->wordchrs, lp, rp, dir); |
| /* (no need for special attention to \n) */ |
| } |
| |
| /* |
| * scannum - scan a number |
| */ |
| static int /* value, <= DUPMAX */ |
| scannum(struct vars * v) |
| { |
| int n = 0; |
| |
| while (SEE(DIGIT) && n < DUPMAX) |
| { |
| n = n * 10 + v->nextvalue; |
| NEXT(); |
| } |
| if (SEE(DIGIT) || n > DUPMAX) |
| { |
| ERR(REG_BADBR); |
| return 0; |
| } |
| return n; |
| } |
| |
| /* |
| * repeat - replicate subNFA for quantifiers |
| * |
| * The duplication sequences used here are chosen carefully so that any |
| * pointers starting out pointing into the subexpression end up pointing into |
| * the last occurrence. (Note that it may not be strung between the same |
| * left and right end states, however!) This used to be important for the |
| * subRE tree, although the important bits are now handled by the in-line |
| * code in parse(), and when this is called, it doesn't matter any more. |
| */ |
| static void |
| repeat(struct vars * v, |
| struct state * lp, |
| struct state * rp, |
| int m, |
| int n) |
| { |
| #define SOME 2 |
| #define INF 3 |
| #define PAIR(x, y) ((x)*4 + (y)) |
| #define REDUCE(x) ( ((x) == INFINITY) ? INF : (((x) > 1) ? SOME : (x)) ) |
| const int rm = REDUCE(m); |
| const int rn = REDUCE(n); |
| struct state *s; |
| struct state *s2; |
| |
| switch (PAIR(rm, rn)) |
| { |
| case PAIR(0, 0): /* empty string */ |
| delsub(v->nfa, lp, rp); |
| EMPTYARC(lp, rp); |
| break; |
| case PAIR(0, 1): /* do as x| */ |
| EMPTYARC(lp, rp); |
| break; |
| case PAIR(0, SOME): /* do as x{1,n}| */ |
| repeat(v, lp, rp, 1, n); |
| NOERR(); |
| EMPTYARC(lp, rp); |
| break; |
| case PAIR(0, INF): /* loop x around */ |
| s = newstate(v->nfa); |
| NOERR(); |
| moveouts(v->nfa, lp, s); |
| moveins(v->nfa, rp, s); |
| EMPTYARC(lp, s); |
| EMPTYARC(s, rp); |
| break; |
| case PAIR(1, 1): /* no action required */ |
| break; |
| case PAIR(1, SOME): /* do as x{0,n-1}x = (x{1,n-1}|)x */ |
| s = newstate(v->nfa); |
| NOERR(); |
| moveouts(v->nfa, lp, s); |
| dupnfa(v->nfa, s, rp, lp, s); |
| NOERR(); |
| repeat(v, lp, s, 1, n - 1); |
| NOERR(); |
| EMPTYARC(lp, s); |
| break; |
| case PAIR(1, INF): /* add loopback arc */ |
| s = newstate(v->nfa); |
| s2 = newstate(v->nfa); |
| NOERR(); |
| moveouts(v->nfa, lp, s); |
| moveins(v->nfa, rp, s2); |
| EMPTYARC(lp, s); |
| EMPTYARC(s2, rp); |
| EMPTYARC(s2, s); |
| break; |
| case PAIR(SOME, SOME): /* do as x{m-1,n-1}x */ |
| s = newstate(v->nfa); |
| NOERR(); |
| moveouts(v->nfa, lp, s); |
| dupnfa(v->nfa, s, rp, lp, s); |
| NOERR(); |
| repeat(v, lp, s, m - 1, n - 1); |
| break; |
| case PAIR(SOME, INF): /* do as x{m-1,}x */ |
| s = newstate(v->nfa); |
| NOERR(); |
| moveouts(v->nfa, lp, s); |
| dupnfa(v->nfa, s, rp, lp, s); |
| NOERR(); |
| repeat(v, lp, s, m - 1, n); |
| break; |
| default: |
| ERR(REG_ASSERT); |
| break; |
| } |
| } |
| |
| /* |
| * bracket - handle non-complemented bracket expression |
| * Also called from cbracket for complemented bracket expressions. |
| */ |
| static void |
| bracket(struct vars * v, |
| struct state * lp, |
| struct state * rp) |
| { |
| assert(SEE('[')); |
| NEXT(); |
| while (!SEE(']') && !SEE(EOS)) |
| brackpart(v, lp, rp); |
| assert(SEE(']') || ISERR()); |
| okcolors(v->nfa, v->cm); |
| } |
| |
| /* |
| * cbracket - handle complemented bracket expression |
| * We do it by calling bracket() with dummy endpoints, and then complementing |
| * the result. The alternative would be to invoke rainbow(), and then delete |
| * arcs as the b.e. is seen... but that gets messy. |
| */ |
| static void |
| cbracket(struct vars * v, |
| struct state * lp, |
| struct state * rp) |
| { |
| struct state *left = newstate(v->nfa); |
| struct state *right = newstate(v->nfa); |
| |
| NOERR(); |
| bracket(v, left, right); |
| if (v->cflags & REG_NLSTOP) |
| newarc(v->nfa, PLAIN, v->nlcolor, left, right); |
| NOERR(); |
| |
| assert(lp->nouts == 0); /* all outarcs will be ours */ |
| |
| /* |
| * Easy part of complementing, and all there is to do since the MCCE code |
| * was removed. |
| */ |
| colorcomplement(v->nfa, v->cm, PLAIN, left, lp, rp); |
| NOERR(); |
| dropstate(v->nfa, left); |
| assert(right->nins == 0); |
| freestate(v->nfa, right); |
| } |
| |
| /* |
| * brackpart - handle one item (or range) within a bracket expression |
| */ |
| static void |
| brackpart(struct vars * v, |
| struct state * lp, |
| struct state * rp) |
| { |
| celt startc; |
| celt endc; |
| struct cvec *cv; |
| const chr *startp; |
| const chr *endp; |
| chr c[1]; |
| |
| /* parse something, get rid of special cases, take shortcuts */ |
| switch (v->nexttype) |
| { |
| case RANGE: /* a-b-c or other botch */ |
| ERR(REG_ERANGE); |
| return; |
| break; |
| case PLAIN: |
| c[0] = v->nextvalue; |
| NEXT(); |
| /* shortcut for ordinary chr (not range) */ |
| if (!SEE(RANGE)) |
| { |
| onechr(v, c[0], lp, rp); |
| return; |
| } |
| startc = element(v, c, c + 1); |
| NOERR(); |
| break; |
| case COLLEL: |
| startp = v->now; |
| endp = scanplain(v); |
| INSIST(startp < endp, REG_ECOLLATE); |
| NOERR(); |
| startc = element(v, startp, endp); |
| NOERR(); |
| break; |
| case ECLASS: |
| startp = v->now; |
| endp = scanplain(v); |
| INSIST(startp < endp, REG_ECOLLATE); |
| NOERR(); |
| startc = element(v, startp, endp); |
| NOERR(); |
| cv = eclass(v, startc, (v->cflags & REG_ICASE)); |
| NOERR(); |
| dovec(v, cv, lp, rp); |
| return; |
| break; |
| case CCLASS: |
| startp = v->now; |
| endp = scanplain(v); |
| INSIST(startp < endp, REG_ECTYPE); |
| NOERR(); |
| cv = cclass(v, startp, endp, (v->cflags & REG_ICASE)); |
| NOERR(); |
| dovec(v, cv, lp, rp); |
| return; |
| break; |
| default: |
| ERR(REG_ASSERT); |
| return; |
| break; |
| } |
| |
| if (SEE(RANGE)) |
| { |
| NEXT(); |
| switch (v->nexttype) |
| { |
| case PLAIN: |
| case RANGE: |
| c[0] = v->nextvalue; |
| NEXT(); |
| endc = element(v, c, c + 1); |
| NOERR(); |
| break; |
| case COLLEL: |
| startp = v->now; |
| endp = scanplain(v); |
| INSIST(startp < endp, REG_ECOLLATE); |
| NOERR(); |
| endc = element(v, startp, endp); |
| NOERR(); |
| break; |
| default: |
| ERR(REG_ERANGE); |
| return; |
| break; |
| } |
| } |
| else |
| endc = startc; |
| |
| /* |
| * Ranges are unportable. Actually, standard C does guarantee that digits |
| * are contiguous, but making that an exception is just too complicated. |
| */ |
| if (startc != endc) |
| NOTE(REG_UUNPORT); |
| cv = range(v, startc, endc, (v->cflags & REG_ICASE)); |
| NOERR(); |
| dovec(v, cv, lp, rp); |
| } |
| |
| /* |
| * scanplain - scan PLAIN contents of [. etc. |
| * |
| * Certain bits of trickery in lex.c know that this code does not try |
| * to look past the final bracket of the [. etc. |
| */ |
| static const chr * /* just after end of sequence */ |
| scanplain(struct vars * v) |
| { |
| const chr *endp; |
| |
| assert(SEE(COLLEL) || SEE(ECLASS) || SEE(CCLASS)); |
| NEXT(); |
| |
| endp = v->now; |
| while (SEE(PLAIN)) |
| { |
| endp = v->now; |
| NEXT(); |
| } |
| |
| assert(SEE(END) || ISERR()); |
| NEXT(); |
| |
| return endp; |
| } |
| |
| /* |
| * onechr - fill in arcs for a plain character, and possible case complements |
| * This is mostly a shortcut for efficient handling of the common case. |
| */ |
| static void |
| onechr(struct vars * v, |
| chr c, |
| struct state * lp, |
| struct state * rp) |
| { |
| if (!(v->cflags & REG_ICASE)) |
| { |
| newarc(v->nfa, PLAIN, subcolor(v->cm, c), lp, rp); |
| return; |
| } |
| |
| /* rats, need general case anyway... */ |
| dovec(v, allcases(v, c), lp, rp); |
| } |
| |
| /* |
| * dovec - fill in arcs for each element of a cvec |
| */ |
| static void |
| dovec(struct vars * v, |
| struct cvec * cv, |
| struct state * lp, |
| struct state * rp) |
| { |
| chr ch, |
| from, |
| to; |
| const chr *p; |
| int i; |
| |
| /* ordinary characters */ |
| for (p = cv->chrs, i = cv->nchrs; i > 0; p++, i--) |
| { |
| ch = *p; |
| newarc(v->nfa, PLAIN, subcolor(v->cm, ch), lp, rp); |
| NOERR(); |
| } |
| |
| /* and the ranges */ |
| for (p = cv->ranges, i = cv->nranges; i > 0; p += 2, i--) |
| { |
| from = *p; |
| to = *(p + 1); |
| if (from <= to) |
| subrange(v, from, to, lp, rp); |
| NOERR(); |
| } |
| } |
| |
| /* |
| * wordchrs - set up word-chr list for word-boundary stuff, if needed |
| * |
| * The list is kept as a bunch of arcs between two dummy states; it's |
| * disposed of by the unreachable-states sweep in NFA optimization. |
| * Does NEXT(). Must not be called from any unusual lexical context. |
| * This should be reconciled with the \w etc. handling in lex.c, and |
| * should be cleaned up to reduce dependencies on input scanning. |
| */ |
| static void |
| wordchrs(struct vars * v) |
| { |
| struct state *left; |
| struct state *right; |
| |
| if (v->wordchrs != NULL) |
| { |
| NEXT(); /* for consistency */ |
| return; |
| } |
| |
| left = newstate(v->nfa); |
| right = newstate(v->nfa); |
| NOERR(); |
| /* fine point: implemented with [::], and lexer will set REG_ULOCALE */ |
| lexword(v); |
| NEXT(); |
| assert(v->savenow != NULL && SEE('[')); |
| bracket(v, left, right); |
| assert((v->savenow != NULL && SEE(']')) || ISERR()); |
| NEXT(); |
| NOERR(); |
| v->wordchrs = left; |
| } |
| |
| /* |
| * subre - allocate a subre |
| */ |
| static struct subre * |
| subre(struct vars * v, |
| int op, |
| int flags, |
| struct state * begin, |
| struct state * end) |
| { |
| struct subre *ret = v->treefree; |
| |
| if (ret != NULL) |
| v->treefree = ret->left; |
| else |
| { |
| ret = (struct subre *) MALLOC(sizeof(struct subre)); |
| if (ret == NULL) |
| { |
| ERR(REG_ESPACE); |
| return NULL; |
| } |
| ret->chain = v->treechain; |
| v->treechain = ret; |
| } |
| |
| assert(strchr("|.b(=", op) != NULL); |
| |
| ret->op = op; |
| ret->flags = flags; |
| ret->retry = 0; |
| ret->subno = 0; |
| ret->min = ret->max = 1; |
| ret->left = NULL; |
| ret->right = NULL; |
| ret->begin = begin; |
| ret->end = end; |
| ZAPCNFA(ret->cnfa); |
| |
| return ret; |
| } |
| |
| /* |
| * freesubre - free a subRE subtree |
| */ |
| static void |
| freesubre(struct vars * v, /* might be NULL */ |
| struct subre * sr) |
| { |
| if (sr == NULL) |
| return; |
| |
| if (sr->left != NULL) |
| freesubre(v, sr->left); |
| if (sr->right != NULL) |
| freesubre(v, sr->right); |
| |
| freesrnode(v, sr); |
| } |
| |
| /* |
| * freesrnode - free one node in a subRE subtree |
| */ |
| static void |
| freesrnode(struct vars * v, /* might be NULL */ |
| struct subre * sr) |
| { |
| if (sr == NULL) |
| return; |
| |
| if (!NULLCNFA(sr->cnfa)) |
| freecnfa(&sr->cnfa); |
| sr->flags = 0; |
| |
| if (v != NULL) |
| { |
| sr->left = v->treefree; |
| v->treefree = sr; |
| } |
| else |
| FREE(sr); |
| } |
| |
| /* |
| * optst - optimize a subRE subtree |
| */ |
| static void |
| optst(struct vars * v, |
| struct subre * t) |
| { |
| /* |
| * DGP (2007-11-13): I assume it was the programmer's intent to eventually |
| * come back and add code to optimize subRE trees, but the routine coded |
| * just spends effort traversing the tree and doing nothing. We can do |
| * nothing with less effort. |
| */ |
| return; |
| } |
| |
| /* |
| * numst - number tree nodes (assigning retry indexes) |
| */ |
| static int /* next number */ |
| numst(struct subre * t, |
| int start) /* starting point for subtree numbers */ |
| { |
| int i; |
| |
| assert(t != NULL); |
| |
| i = start; |
| t->retry = (short) i++; |
| if (t->left != NULL) |
| i = numst(t->left, i); |
| if (t->right != NULL) |
| i = numst(t->right, i); |
| return i; |
| } |
| |
| /* |
| * markst - mark tree nodes as INUSE |
| */ |
| static void |
| markst(struct subre * t) |
| { |
| assert(t != NULL); |
| |
| t->flags |= INUSE; |
| if (t->left != NULL) |
| markst(t->left); |
| if (t->right != NULL) |
| markst(t->right); |
| } |
| |
| /* |
| * cleanst - free any tree nodes not marked INUSE |
| */ |
| static void |
| cleanst(struct vars * v) |
| { |
| struct subre *t; |
| struct subre *next; |
| |
| for (t = v->treechain; t != NULL; t = next) |
| { |
| next = t->chain; |
| if (!(t->flags & INUSE)) |
| FREE(t); |
| } |
| v->treechain = NULL; |
| v->treefree = NULL; /* just on general principles */ |
| } |
| |
| /* |
| * nfatree - turn a subRE subtree into a tree of compacted NFAs |
| */ |
| static long /* optimize results from top node */ |
| nfatree(struct vars * v, |
| struct subre * t, |
| FILE *f) /* for debug output */ |
| { |
| assert(t != NULL && t->begin != NULL); |
| |
| if (t->left != NULL) |
| (DISCARD) nfatree(v, t->left, f); |
| if (t->right != NULL) |
| (DISCARD) nfatree(v, t->right, f); |
| |
| return nfanode(v, t, f); |
| } |
| |
| /* |
| * nfanode - do one NFA for nfatree |
| */ |
| static long /* optimize results */ |
| nfanode(struct vars * v, |
| struct subre * t, |
| FILE *f) /* for debug output */ |
| { |
| struct nfa *nfa; |
| long ret = 0; |
| |
| assert(t->begin != NULL); |
| |
| #ifdef REG_DEBUG |
| if (f != NULL) |
| { |
| char idbuf[50]; |
| |
| fprintf(f, "\n\n\n========= TREE NODE %s ==========\n", |
| stid(t, idbuf, sizeof(idbuf))); |
| } |
| #endif |
| nfa = newnfa(v, v->cm, v->nfa); |
| NOERRZ(); |
| dupnfa(nfa, t->begin, t->end, nfa->init, nfa->final); |
| if (!ISERR()) |
| { |
| specialcolors(nfa); |
| ret = optimize(nfa, f); |
| } |
| if (!ISERR()) |
| compact(nfa, &t->cnfa); |
| |
| freenfa(nfa); |
| return ret; |
| } |
| |
| /* |
| * newlacon - allocate a lookahead-constraint subRE |
| */ |
| static int /* lacon number */ |
| newlacon(struct vars * v, |
| struct state * begin, |
| struct state * end, |
| int pos) |
| { |
| int n; |
| struct subre *sub; |
| |
| if (v->nlacons == 0) |
| { |
| v->lacons = (struct subre *) MALLOC(2 * sizeof(struct subre)); |
| n = 1; /* skip 0th */ |
| v->nlacons = 2; |
| } |
| else |
| { |
| v->lacons = (struct subre *) REALLOC(v->lacons, |
| (v->nlacons + 1) * sizeof(struct subre)); |
| n = v->nlacons++; |
| } |
| if (v->lacons == NULL) |
| { |
| ERR(REG_ESPACE); |
| return 0; |
| } |
| sub = &v->lacons[n]; |
| sub->begin = begin; |
| sub->end = end; |
| sub->subno = pos; |
| ZAPCNFA(sub->cnfa); |
| return n; |
| } |
| |
| /* |
| * freelacons - free lookahead-constraint subRE vector |
| */ |
| static void |
| freelacons(struct subre * subs, |
| int n) |
| { |
| struct subre *sub; |
| int i; |
| |
| assert(n > 0); |
| for (sub = subs + 1, i = n - 1; i > 0; sub++, i--) /* no 0th */ |
| if (!NULLCNFA(sub->cnfa)) |
| freecnfa(&sub->cnfa); |
| FREE(subs); |
| } |
| |
| /* |
| * rfree - free a whole RE (insides of regfree) |
| */ |
| static void |
| rfree(regex_t *re) |
| { |
| struct guts *g; |
| |
| if (re == NULL || re->re_magic != REMAGIC) |
| return; |
| |
| re->re_magic = 0; /* invalidate RE */ |
| g = (struct guts *) re->re_guts; |
| re->re_guts = NULL; |
| re->re_fns = NULL; |
| g->magic = 0; |
| freecm(&g->cmap); |
| if (g->tree != NULL) |
| freesubre((struct vars *) NULL, g->tree); |
| if (g->lacons != NULL) |
| freelacons(g->lacons, g->nlacons); |
| if (!NULLCNFA(g->search)) |
| freecnfa(&g->search); |
| FREE(g); |
| } |
| |
| |
| #ifdef REG_DEBUG |
| |
| /* |
| * dump - dump an RE in human-readable form |
| */ |
| static void |
| dump(regex_t *re, |
| FILE *f) |
| { |
| struct guts *g; |
| int i; |
| |
| if (re->re_magic != REMAGIC) |
| fprintf(f, "bad magic number (0x%x not 0x%x)\n", re->re_magic, |
| REMAGIC); |
| if (re->re_guts == NULL) |
| { |
| fprintf(f, "NULL guts!!!\n"); |
| return; |
| } |
| g = (struct guts *) re->re_guts; |
| if (g->magic != GUTSMAGIC) |
| fprintf(f, "bad guts magic number (0x%x not 0x%x)\n", g->magic, |
| GUTSMAGIC); |
| |
| fprintf(f, "\n\n\n========= DUMP ==========\n"); |
| fprintf(f, "nsub %d, info 0%lo, csize %d, ntree %d\n", |
| (int) re->re_nsub, re->re_info, re->re_csize, g->ntree); |
| |
| dumpcolors(&g->cmap, f); |
| if (!NULLCNFA(g->search)) |
| { |
| printf("\nsearch:\n"); |
| dumpcnfa(&g->search, f); |
| } |
| for (i = 1; i < g->nlacons; i++) |
| { |
| fprintf(f, "\nla%d (%s):\n", i, |
| (g->lacons[i].subno) ? "positive" : "negative"); |
| dumpcnfa(&g->lacons[i].cnfa, f); |
| } |
| fprintf(f, "\n"); |
| dumpst(g->tree, f, 0); |
| } |
| |
| /* |
| * dumpst - dump a subRE tree |
| */ |
| static void |
| dumpst(struct subre * t, |
| FILE *f, |
| int nfapresent) /* is the original NFA still around? */ |
| { |
| if (t == NULL) |
| fprintf(f, "null tree\n"); |
| else |
| stdump(t, f, nfapresent); |
| fflush(f); |
| } |
| |
| /* |
| * stdump - recursive guts of dumpst |
| */ |
| static void |
| stdump(struct subre * t, |
| FILE *f, |
| int nfapresent) /* is the original NFA still around? */ |
| { |
| char idbuf[50]; |
| |
| fprintf(f, "%s. `%c'", stid(t, idbuf, sizeof(idbuf)), t->op); |
| if (t->flags & LONGER) |
| fprintf(f, " longest"); |
| if (t->flags & SHORTER) |
| fprintf(f, " shortest"); |
| if (t->flags & MIXED) |
| fprintf(f, " hasmixed"); |
| if (t->flags & CAP) |
| fprintf(f, " hascapture"); |
| if (t->flags & BACKR) |
| fprintf(f, " hasbackref"); |
| if (!(t->flags & INUSE)) |
| fprintf(f, " UNUSED"); |
| if (t->subno != 0) |
| fprintf(f, " (#%d)", t->subno); |
| if (t->min != 1 || t->max != 1) |
| { |
| fprintf(f, " {%d,", t->min); |
| if (t->max != INFINITY) |
| fprintf(f, "%d", t->max); |
| fprintf(f, "}"); |
| } |
| if (nfapresent) |
| fprintf(f, " %ld-%ld", (long) t->begin->no, (long) t->end->no); |
| if (t->left != NULL) |
| fprintf(f, " L:%s", stid(t->left, idbuf, sizeof(idbuf))); |
| if (t->right != NULL) |
| fprintf(f, " R:%s", stid(t->right, idbuf, sizeof(idbuf))); |
| if (!NULLCNFA(t->cnfa)) |
| { |
| fprintf(f, "\n"); |
| dumpcnfa(&t->cnfa, f); |
| } |
| fprintf(f, "\n"); |
| if (t->left != NULL) |
| stdump(t->left, f, nfapresent); |
| if (t->right != NULL) |
| stdump(t->right, f, nfapresent); |
| } |
| |
| /* |
| * stid - identify a subtree node for dumping |
| */ |
| static const char * /* points to buf or constant string */ |
| stid(struct subre * t, |
| char *buf, |
| size_t bufsize) |
| { |
| /* big enough for hex int or decimal t->retry? */ |
| if (bufsize < sizeof(void *) * 2 + 3 || bufsize < sizeof(t->retry) * 3 + 1) |
| return "unable"; |
| if (t->retry != 0) |
| sprintf(buf, "%d", t->retry); |
| else |
| sprintf(buf, "%p", t); |
| return buf; |
| } |
| #endif /* REG_DEBUG */ |
| |
| |
| #include "regc_lex.c" |
| #include "regc_color.c" |
| #include "regc_nfa.c" |
| #include "regc_cvec.c" |
| #include "regc_locale.c" |