b.c revision 85587
185587Sobrien/**************************************************************** 285587SobrienCopyright (C) Lucent Technologies 1997 385587SobrienAll Rights Reserved 485587Sobrien 585587SobrienPermission to use, copy, modify, and distribute this software and 685587Sobrienits documentation for any purpose and without fee is hereby 785587Sobriengranted, provided that the above copyright notice appear in all 885587Sobriencopies and that both that the copyright notice and this 985587Sobrienpermission notice and warranty disclaimer appear in supporting 1085587Sobriendocumentation, and that the name Lucent Technologies or any of 1185587Sobrienits entities not be used in advertising or publicity pertaining 1285587Sobriento distribution of the software without specific, written prior 1385587Sobrienpermission. 1485587Sobrien 1585587SobrienLUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 1685587SobrienINCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. 1785587SobrienIN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY 1885587SobrienSPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 1985587SobrienWHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER 2085587SobrienIN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, 2185587SobrienARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF 2285587SobrienTHIS SOFTWARE. 2385587Sobrien****************************************************************/ 2485587Sobrien 2585587Sobrien/* lasciate ogne speranza, voi ch'entrate. */ 2685587Sobrien 2785587Sobrien#define DEBUG 2885587Sobrien 2985587Sobrien#include <ctype.h> 3085587Sobrien#include <stdio.h> 3185587Sobrien#include <string.h> 3285587Sobrien#include <stdlib.h> 3385587Sobrien#include "awk.h" 3485587Sobrien#include "ytab.h" 3585587Sobrien 3685587Sobrien#define HAT (NCHARS-2) /* matches ^ in regular expr */ 3785587Sobrien /* NCHARS is 2**n */ 3885587Sobrien#define MAXLIN 22 3985587Sobrien 4085587Sobrien#define type(v) (v)->nobj /* badly overloaded here */ 4185587Sobrien#define info(v) (v)->ntype /* badly overloaded here */ 4285587Sobrien#define left(v) (v)->narg[0] 4385587Sobrien#define right(v) (v)->narg[1] 4485587Sobrien#define parent(v) (v)->nnext 4585587Sobrien 4685587Sobrien#define LEAF case CCL: case NCCL: case CHAR: case DOT: case FINAL: case ALL: 4785587Sobrien#define UNARY case STAR: case PLUS: case QUEST: 4885587Sobrien 4985587Sobrien/* encoding in tree Nodes: 5085587Sobrien leaf (CCL, NCCL, CHAR, DOT, FINAL, ALL): 5185587Sobrien left is index, right contains value or pointer to value 5285587Sobrien unary (STAR, PLUS, QUEST): left is child, right is null 5385587Sobrien binary (CAT, OR): left and right are children 5485587Sobrien parent contains pointer to parent 5585587Sobrien*/ 5685587Sobrien 5785587Sobrien 5885587Sobrienint *setvec; 5985587Sobrienint *tmpset; 6085587Sobrienint maxsetvec = 0; 6185587Sobrien 6285587Sobrienint rtok; /* next token in current re */ 6385587Sobrienint rlxval; 6485587Sobrienstatic uschar *rlxstr; 6585587Sobrienstatic uschar *prestr; /* current position in current re */ 6685587Sobrienstatic uschar *lastre; /* origin of last re */ 6785587Sobrien 6885587Sobrienstatic int setcnt; 6985587Sobrienstatic int poscnt; 7085587Sobrien 7185587Sobrienchar *patbeg; 7285587Sobrienint patlen; 7385587Sobrien 7485587Sobrien#define NFA 20 /* cache this many dynamic fa's */ 7585587Sobrienfa *fatab[NFA]; 7685587Sobrienint nfatab = 0; /* entries in fatab */ 7785587Sobrien 7885587Sobrienfa *makedfa(char *s, int anchor) /* returns dfa for reg expr s */ 7985587Sobrien{ 8085587Sobrien int i, use, nuse; 8185587Sobrien fa *pfa; 8285587Sobrien static int now = 1; 8385587Sobrien 8485587Sobrien if (setvec == 0) { /* first time through any RE */ 8585587Sobrien maxsetvec = MAXLIN; 8685587Sobrien setvec = (int *) malloc(maxsetvec * sizeof(int)); 8785587Sobrien tmpset = (int *) malloc(maxsetvec * sizeof(int)); 8885587Sobrien if (setvec == 0 || tmpset == 0) 8985587Sobrien overflo("out of space initializing makedfa"); 9085587Sobrien } 9185587Sobrien 9285587Sobrien if (compile_time) /* a constant for sure */ 9385587Sobrien return mkdfa(s, anchor); 9485587Sobrien for (i = 0; i < nfatab; i++) /* is it there already? */ 9585587Sobrien if (fatab[i]->anchor == anchor 9685587Sobrien && strcmp(fatab[i]->restr, s) == 0) { 9785587Sobrien fatab[i]->use = now++; 9885587Sobrien return fatab[i]; 9985587Sobrien } 10085587Sobrien pfa = mkdfa(s, anchor); 10185587Sobrien if (nfatab < NFA) { /* room for another */ 10285587Sobrien fatab[nfatab] = pfa; 10385587Sobrien fatab[nfatab]->use = now++; 10485587Sobrien nfatab++; 10585587Sobrien return pfa; 10685587Sobrien } 10785587Sobrien use = fatab[0]->use; /* replace least-recently used */ 10885587Sobrien nuse = 0; 10985587Sobrien for (i = 1; i < nfatab; i++) 11085587Sobrien if (fatab[i]->use < use) { 11185587Sobrien use = fatab[i]->use; 11285587Sobrien nuse = i; 11385587Sobrien } 11485587Sobrien freefa(fatab[nuse]); 11585587Sobrien fatab[nuse] = pfa; 11685587Sobrien pfa->use = now++; 11785587Sobrien return pfa; 11885587Sobrien} 11985587Sobrien 12085587Sobrienfa *mkdfa(char *s, int anchor) /* does the real work of making a dfa */ 12185587Sobrien /* anchor = 1 for anchored matches, else 0 */ 12285587Sobrien{ 12385587Sobrien Node *p, *p1; 12485587Sobrien fa *f; 12585587Sobrien 12685587Sobrien p = reparse(s); 12785587Sobrien p1 = op2(CAT, op2(STAR, op2(ALL, NIL, NIL), NIL), p); 12885587Sobrien /* put ALL STAR in front of reg. exp. */ 12985587Sobrien p1 = op2(CAT, p1, op2(FINAL, NIL, NIL)); 13085587Sobrien /* put FINAL after reg. exp. */ 13185587Sobrien 13285587Sobrien poscnt = 0; 13385587Sobrien penter(p1); /* enter parent pointers and leaf indices */ 13485587Sobrien if ((f = (fa *) calloc(1, sizeof(fa) + poscnt*sizeof(rrow))) == NULL) 13585587Sobrien overflo("out of space for fa"); 13685587Sobrien f->accept = poscnt-1; /* penter has computed number of positions in re */ 13785587Sobrien cfoll(f, p1); /* set up follow sets */ 13885587Sobrien freetr(p1); 13985587Sobrien if ((f->posns[0] = (int *) calloc(1, *(f->re[0].lfollow)*sizeof(int))) == NULL) 14085587Sobrien overflo("out of space in makedfa"); 14185587Sobrien if ((f->posns[1] = (int *) calloc(1, sizeof(int))) == NULL) 14285587Sobrien overflo("out of space in makedfa"); 14385587Sobrien *f->posns[1] = 0; 14485587Sobrien f->initstat = makeinit(f, anchor); 14585587Sobrien f->anchor = anchor; 14685587Sobrien f->restr = (uschar *) tostring(s); 14785587Sobrien return f; 14885587Sobrien} 14985587Sobrien 15085587Sobrienint makeinit(fa *f, int anchor) 15185587Sobrien{ 15285587Sobrien int i, k; 15385587Sobrien 15485587Sobrien f->curstat = 2; 15585587Sobrien f->out[2] = 0; 15685587Sobrien f->reset = 0; 15785587Sobrien k = *(f->re[0].lfollow); 15885587Sobrien xfree(f->posns[2]); 15985587Sobrien if ((f->posns[2] = (int *) calloc(1, (k+1)*sizeof(int))) == NULL) 16085587Sobrien overflo("out of space in makeinit"); 16185587Sobrien for (i=0; i <= k; i++) { 16285587Sobrien (f->posns[2])[i] = (f->re[0].lfollow)[i]; 16385587Sobrien } 16485587Sobrien if ((f->posns[2])[1] == f->accept) 16585587Sobrien f->out[2] = 1; 16685587Sobrien for (i=0; i < NCHARS; i++) 16785587Sobrien f->gototab[2][i] = 0; 16885587Sobrien f->curstat = cgoto(f, 2, HAT); 16985587Sobrien if (anchor) { 17085587Sobrien *f->posns[2] = k-1; /* leave out position 0 */ 17185587Sobrien for (i=0; i < k; i++) { 17285587Sobrien (f->posns[0])[i] = (f->posns[2])[i]; 17385587Sobrien } 17485587Sobrien 17585587Sobrien f->out[0] = f->out[2]; 17685587Sobrien if (f->curstat != 2) 17785587Sobrien --(*f->posns[f->curstat]); 17885587Sobrien } 17985587Sobrien return f->curstat; 18085587Sobrien} 18185587Sobrien 18285587Sobrienvoid penter(Node *p) /* set up parent pointers and leaf indices */ 18385587Sobrien{ 18485587Sobrien switch (type(p)) { 18585587Sobrien LEAF 18685587Sobrien info(p) = poscnt; 18785587Sobrien poscnt++; 18885587Sobrien break; 18985587Sobrien UNARY 19085587Sobrien penter(left(p)); 19185587Sobrien parent(left(p)) = p; 19285587Sobrien break; 19385587Sobrien case CAT: 19485587Sobrien case OR: 19585587Sobrien penter(left(p)); 19685587Sobrien penter(right(p)); 19785587Sobrien parent(left(p)) = p; 19885587Sobrien parent(right(p)) = p; 19985587Sobrien break; 20085587Sobrien default: /* can't happen */ 20185587Sobrien FATAL("can't happen: unknown type %d in penter", type(p)); 20285587Sobrien break; 20385587Sobrien } 20485587Sobrien} 20585587Sobrien 20685587Sobrienvoid freetr(Node *p) /* free parse tree */ 20785587Sobrien{ 20885587Sobrien switch (type(p)) { 20985587Sobrien LEAF 21085587Sobrien xfree(p); 21185587Sobrien break; 21285587Sobrien UNARY 21385587Sobrien freetr(left(p)); 21485587Sobrien xfree(p); 21585587Sobrien break; 21685587Sobrien case CAT: 21785587Sobrien case OR: 21885587Sobrien freetr(left(p)); 21985587Sobrien freetr(right(p)); 22085587Sobrien xfree(p); 22185587Sobrien break; 22285587Sobrien default: /* can't happen */ 22385587Sobrien FATAL("can't happen: unknown type %d in freetr", type(p)); 22485587Sobrien break; 22585587Sobrien } 22685587Sobrien} 22785587Sobrien 22885587Sobrien/* in the parsing of regular expressions, metacharacters like . have */ 22985587Sobrien/* to be seen literally; \056 is not a metacharacter. */ 23085587Sobrien 23185587Sobrienint hexstr(char **pp) /* find and eval hex string at pp, return new p */ 23285587Sobrien{ /* only pick up one 8-bit byte (2 chars) */ 23385587Sobrien uschar *p; 23485587Sobrien int n = 0; 23585587Sobrien int i; 23685587Sobrien 23785587Sobrien for (i = 0, p = (uschar *) *pp; i < 2 && isxdigit(*p); i++, p++) { 23885587Sobrien if (isdigit(*p)) 23985587Sobrien n = 16 * n + *p - '0'; 24085587Sobrien else if (*p >= 'a' && *p <= 'f') 24185587Sobrien n = 16 * n + *p - 'a' + 10; 24285587Sobrien else if (*p >= 'A' && *p <= 'F') 24385587Sobrien n = 16 * n + *p - 'A' + 10; 24485587Sobrien } 24585587Sobrien *pp = (char *) p; 24685587Sobrien return n; 24785587Sobrien} 24885587Sobrien 24985587Sobrien#define isoctdigit(c) ((c) >= '0' && (c) <= '7') /* multiple use of arg */ 25085587Sobrien 25185587Sobrienint quoted(char **pp) /* pick up next thing after a \\ */ 25285587Sobrien /* and increment *pp */ 25385587Sobrien{ 25485587Sobrien char *p = *pp; 25585587Sobrien int c; 25685587Sobrien 25785587Sobrien if ((c = *p++) == 't') 25885587Sobrien c = '\t'; 25985587Sobrien else if (c == 'n') 26085587Sobrien c = '\n'; 26185587Sobrien else if (c == 'f') 26285587Sobrien c = '\f'; 26385587Sobrien else if (c == 'r') 26485587Sobrien c = '\r'; 26585587Sobrien else if (c == 'b') 26685587Sobrien c = '\b'; 26785587Sobrien else if (c == '\\') 26885587Sobrien c = '\\'; 26985587Sobrien else if (c == 'x') { /* hexadecimal goo follows */ 27085587Sobrien c = hexstr(&p); /* this adds a null if number is invalid */ 27185587Sobrien } else if (isoctdigit(c)) { /* \d \dd \ddd */ 27285587Sobrien int n = c - '0'; 27385587Sobrien if (isoctdigit(*p)) { 27485587Sobrien n = 8 * n + *p++ - '0'; 27585587Sobrien if (isoctdigit(*p)) 27685587Sobrien n = 8 * n + *p++ - '0'; 27785587Sobrien } 27885587Sobrien c = n; 27985587Sobrien } /* else */ 28085587Sobrien /* c = c; */ 28185587Sobrien *pp = p; 28285587Sobrien return c; 28385587Sobrien} 28485587Sobrien 28585587Sobrienchar *cclenter(char *argp) /* add a character class */ 28685587Sobrien{ 28785587Sobrien int i, c, c2; 28885587Sobrien uschar *p = (uschar *) argp; 28985587Sobrien uschar *op, *bp; 29085587Sobrien static uschar *buf = 0; 29185587Sobrien static int bufsz = 100; 29285587Sobrien 29385587Sobrien op = p; 29485587Sobrien if (buf == 0 && (buf = (uschar *) malloc(bufsz)) == NULL) 29585587Sobrien FATAL("out of space for character class [%.10s...] 1", p); 29685587Sobrien bp = buf; 29785587Sobrien for (i = 0; (c = *p++) != 0; ) { 29885587Sobrien if (c == '\\') { 29985587Sobrien c = quoted((char **) &p); 30085587Sobrien } else if (c == '-' && i > 0 && bp[-1] != 0) { 30185587Sobrien if (*p != 0) { 30285587Sobrien c = bp[-1]; 30385587Sobrien c2 = *p++; 30485587Sobrien if (c2 == '\\') 30585587Sobrien c2 = quoted((char **) &p); 30685587Sobrien if (c > c2) { /* empty; ignore */ 30785587Sobrien bp--; 30885587Sobrien i--; 30985587Sobrien continue; 31085587Sobrien } 31185587Sobrien while (c < c2) { 31285587Sobrien if (!adjbuf((char **) &buf, &bufsz, bp-buf+2, 100, (char **) &bp, 0)) 31385587Sobrien FATAL("out of space for character class [%.10s...] 2", p); 31485587Sobrien *bp++ = ++c; 31585587Sobrien i++; 31685587Sobrien } 31785587Sobrien continue; 31885587Sobrien } 31985587Sobrien } 32085587Sobrien if (!adjbuf((char **) &buf, &bufsz, bp-buf+2, 100, (char **) &bp, 0)) 32185587Sobrien FATAL("out of space for character class [%.10s...] 3", p); 32285587Sobrien *bp++ = c; 32385587Sobrien i++; 32485587Sobrien } 32585587Sobrien *bp = 0; 32685587Sobrien dprintf( ("cclenter: in = |%s|, out = |%s|\n", op, buf) ); 32785587Sobrien xfree(op); 32885587Sobrien return (char *) tostring((char *) buf); 32985587Sobrien} 33085587Sobrien 33185587Sobrienvoid overflo(char *s) 33285587Sobrien{ 33385587Sobrien FATAL("regular expression too big: %.30s...", s); 33485587Sobrien} 33585587Sobrien 33685587Sobrienvoid cfoll(fa *f, Node *v) /* enter follow set of each leaf of vertex v into lfollow[leaf] */ 33785587Sobrien{ 33885587Sobrien int i; 33985587Sobrien int *p; 34085587Sobrien 34185587Sobrien switch (type(v)) { 34285587Sobrien LEAF 34385587Sobrien f->re[info(v)].ltype = type(v); 34485587Sobrien f->re[info(v)].lval.np = right(v); 34585587Sobrien while (f->accept >= maxsetvec) { /* guessing here! */ 34685587Sobrien maxsetvec *= 4; 34785587Sobrien setvec = (int *) realloc(setvec, maxsetvec * sizeof(int)); 34885587Sobrien tmpset = (int *) realloc(tmpset, maxsetvec * sizeof(int)); 34985587Sobrien if (setvec == 0 || tmpset == 0) 35085587Sobrien overflo("out of space in cfoll()"); 35185587Sobrien } 35285587Sobrien for (i = 0; i <= f->accept; i++) 35385587Sobrien setvec[i] = 0; 35485587Sobrien setcnt = 0; 35585587Sobrien follow(v); /* computes setvec and setcnt */ 35685587Sobrien if ((p = (int *) calloc(1, (setcnt+1)*sizeof(int))) == NULL) 35785587Sobrien overflo("out of space building follow set"); 35885587Sobrien f->re[info(v)].lfollow = p; 35985587Sobrien *p = setcnt; 36085587Sobrien for (i = f->accept; i >= 0; i--) 36185587Sobrien if (setvec[i] == 1) 36285587Sobrien *++p = i; 36385587Sobrien break; 36485587Sobrien UNARY 36585587Sobrien cfoll(f,left(v)); 36685587Sobrien break; 36785587Sobrien case CAT: 36885587Sobrien case OR: 36985587Sobrien cfoll(f,left(v)); 37085587Sobrien cfoll(f,right(v)); 37185587Sobrien break; 37285587Sobrien default: /* can't happen */ 37385587Sobrien FATAL("can't happen: unknown type %d in cfoll", type(v)); 37485587Sobrien } 37585587Sobrien} 37685587Sobrien 37785587Sobrienint first(Node *p) /* collects initially active leaves of p into setvec */ 37885587Sobrien /* returns 1 if p matches empty string */ 37985587Sobrien{ 38085587Sobrien int b, lp; 38185587Sobrien 38285587Sobrien switch (type(p)) { 38385587Sobrien LEAF 38485587Sobrien lp = info(p); /* look for high-water mark of subscripts */ 38585587Sobrien while (setcnt >= maxsetvec || lp >= maxsetvec) { /* guessing here! */ 38685587Sobrien maxsetvec *= 4; 38785587Sobrien setvec = (int *) realloc(setvec, maxsetvec * sizeof(int)); 38885587Sobrien tmpset = (int *) realloc(tmpset, maxsetvec * sizeof(int)); 38985587Sobrien if (setvec == 0 || tmpset == 0) 39085587Sobrien overflo("out of space in first()"); 39185587Sobrien } 39285587Sobrien if (setvec[lp] != 1) { 39385587Sobrien setvec[lp] = 1; 39485587Sobrien setcnt++; 39585587Sobrien } 39685587Sobrien if (type(p) == CCL && (*(char *) right(p)) == '\0') 39785587Sobrien return(0); /* empty CCL */ 39885587Sobrien else return(1); 39985587Sobrien case PLUS: 40085587Sobrien if (first(left(p)) == 0) return(0); 40185587Sobrien return(1); 40285587Sobrien case STAR: 40385587Sobrien case QUEST: 40485587Sobrien first(left(p)); 40585587Sobrien return(0); 40685587Sobrien case CAT: 40785587Sobrien if (first(left(p)) == 0 && first(right(p)) == 0) return(0); 40885587Sobrien return(1); 40985587Sobrien case OR: 41085587Sobrien b = first(right(p)); 41185587Sobrien if (first(left(p)) == 0 || b == 0) return(0); 41285587Sobrien return(1); 41385587Sobrien } 41485587Sobrien FATAL("can't happen: unknown type %d in first", type(p)); /* can't happen */ 41585587Sobrien return(-1); 41685587Sobrien} 41785587Sobrien 41885587Sobrienvoid follow(Node *v) /* collects leaves that can follow v into setvec */ 41985587Sobrien{ 42085587Sobrien Node *p; 42185587Sobrien 42285587Sobrien if (type(v) == FINAL) 42385587Sobrien return; 42485587Sobrien p = parent(v); 42585587Sobrien switch (type(p)) { 42685587Sobrien case STAR: 42785587Sobrien case PLUS: 42885587Sobrien first(v); 42985587Sobrien follow(p); 43085587Sobrien return; 43185587Sobrien 43285587Sobrien case OR: 43385587Sobrien case QUEST: 43485587Sobrien follow(p); 43585587Sobrien return; 43685587Sobrien 43785587Sobrien case CAT: 43885587Sobrien if (v == left(p)) { /* v is left child of p */ 43985587Sobrien if (first(right(p)) == 0) { 44085587Sobrien follow(p); 44185587Sobrien return; 44285587Sobrien } 44385587Sobrien } else /* v is right child */ 44485587Sobrien follow(p); 44585587Sobrien return; 44685587Sobrien } 44785587Sobrien} 44885587Sobrien 44985587Sobrienint member(int c, char *sarg) /* is c in s? */ 45085587Sobrien{ 45185587Sobrien uschar *s = (uschar *) sarg; 45285587Sobrien 45385587Sobrien while (*s) 45485587Sobrien if (c == *s++) 45585587Sobrien return(1); 45685587Sobrien return(0); 45785587Sobrien} 45885587Sobrien 45985587Sobrienint match(fa *f, char *p0) /* shortest match ? */ 46085587Sobrien{ 46185587Sobrien int s, ns; 46285587Sobrien uschar *p = (uschar *) p0; 46385587Sobrien 46485587Sobrien s = f->reset ? makeinit(f,0) : f->initstat; 46585587Sobrien if (f->out[s]) 46685587Sobrien return(1); 46785587Sobrien do { 46885587Sobrien if ((ns = f->gototab[s][*p]) != 0) 46985587Sobrien s = ns; 47085587Sobrien else 47185587Sobrien s = cgoto(f, s, *p); 47285587Sobrien if (f->out[s]) 47385587Sobrien return(1); 47485587Sobrien } while (*p++ != 0); 47585587Sobrien return(0); 47685587Sobrien} 47785587Sobrien 47885587Sobrienint pmatch(fa *f, char *p0) /* longest match, for sub */ 47985587Sobrien{ 48085587Sobrien int s, ns; 48185587Sobrien uschar *p = (uschar *) p0; 48285587Sobrien uschar *q; 48385587Sobrien int i, k; 48485587Sobrien 48585587Sobrien s = f->reset ? makeinit(f,1) : f->initstat; 48685587Sobrien patbeg = (char *) p; 48785587Sobrien patlen = -1; 48885587Sobrien do { 48985587Sobrien q = p; 49085587Sobrien do { 49185587Sobrien if (f->out[s]) /* final state */ 49285587Sobrien patlen = q-p; 49385587Sobrien if ((ns = f->gototab[s][*q]) != 0) 49485587Sobrien s = ns; 49585587Sobrien else 49685587Sobrien s = cgoto(f, s, *q); 49785587Sobrien if (s == 1) { /* no transition */ 49885587Sobrien if (patlen >= 0) { 49985587Sobrien patbeg = (char *) p; 50085587Sobrien return(1); 50185587Sobrien } 50285587Sobrien else 50385587Sobrien goto nextin; /* no match */ 50485587Sobrien } 50585587Sobrien } while (*q++ != 0); 50685587Sobrien if (f->out[s]) 50785587Sobrien patlen = q-p-1; /* don't count $ */ 50885587Sobrien if (patlen >= 0) { 50985587Sobrien patbeg = (char *) p; 51085587Sobrien return(1); 51185587Sobrien } 51285587Sobrien nextin: 51385587Sobrien s = 2; 51485587Sobrien if (f->reset) { 51585587Sobrien for (i = 2; i <= f->curstat; i++) 51685587Sobrien xfree(f->posns[i]); 51785587Sobrien k = *f->posns[0]; 51885587Sobrien if ((f->posns[2] = (int *) calloc(1, (k+1)*sizeof(int))) == NULL) 51985587Sobrien overflo("out of space in pmatch"); 52085587Sobrien for (i = 0; i <= k; i++) 52185587Sobrien (f->posns[2])[i] = (f->posns[0])[i]; 52285587Sobrien f->initstat = f->curstat = 2; 52385587Sobrien f->out[2] = f->out[0]; 52485587Sobrien for (i = 0; i < NCHARS; i++) 52585587Sobrien f->gototab[2][i] = 0; 52685587Sobrien } 52785587Sobrien } while (*p++ != 0); 52885587Sobrien return (0); 52985587Sobrien} 53085587Sobrien 53185587Sobrienint nematch(fa *f, char *p0) /* non-empty match, for sub */ 53285587Sobrien{ 53385587Sobrien int s, ns; 53485587Sobrien uschar *p = (uschar *) p0; 53585587Sobrien uschar *q; 53685587Sobrien int i, k; 53785587Sobrien 53885587Sobrien s = f->reset ? makeinit(f,1) : f->initstat; 53985587Sobrien patlen = -1; 54085587Sobrien while (*p) { 54185587Sobrien q = p; 54285587Sobrien do { 54385587Sobrien if (f->out[s]) /* final state */ 54485587Sobrien patlen = q-p; 54585587Sobrien if ((ns = f->gototab[s][*q]) != 0) 54685587Sobrien s = ns; 54785587Sobrien else 54885587Sobrien s = cgoto(f, s, *q); 54985587Sobrien if (s == 1) { /* no transition */ 55085587Sobrien if (patlen > 0) { 55185587Sobrien patbeg = (char *) p; 55285587Sobrien return(1); 55385587Sobrien } else 55485587Sobrien goto nnextin; /* no nonempty match */ 55585587Sobrien } 55685587Sobrien } while (*q++ != 0); 55785587Sobrien if (f->out[s]) 55885587Sobrien patlen = q-p-1; /* don't count $ */ 55985587Sobrien if (patlen > 0 ) { 56085587Sobrien patbeg = (char *) p; 56185587Sobrien return(1); 56285587Sobrien } 56385587Sobrien nnextin: 56485587Sobrien s = 2; 56585587Sobrien if (f->reset) { 56685587Sobrien for (i = 2; i <= f->curstat; i++) 56785587Sobrien xfree(f->posns[i]); 56885587Sobrien k = *f->posns[0]; 56985587Sobrien if ((f->posns[2] = (int *) calloc(1, (k+1)*sizeof(int))) == NULL) 57085587Sobrien overflo("out of state space"); 57185587Sobrien for (i = 0; i <= k; i++) 57285587Sobrien (f->posns[2])[i] = (f->posns[0])[i]; 57385587Sobrien f->initstat = f->curstat = 2; 57485587Sobrien f->out[2] = f->out[0]; 57585587Sobrien for (i = 0; i < NCHARS; i++) 57685587Sobrien f->gototab[2][i] = 0; 57785587Sobrien } 57885587Sobrien p++; 57985587Sobrien } 58085587Sobrien return (0); 58185587Sobrien} 58285587Sobrien 58385587SobrienNode *reparse(char *p) /* parses regular expression pointed to by p */ 58485587Sobrien{ /* uses relex() to scan regular expression */ 58585587Sobrien Node *np; 58685587Sobrien 58785587Sobrien dprintf( ("reparse <%s>\n", p) ); 58885587Sobrien lastre = prestr = (uschar *) p; /* prestr points to string to be parsed */ 58985587Sobrien rtok = relex(); 59085587Sobrien if (rtok == '\0') 59185587Sobrien FATAL("empty regular expression"); 59285587Sobrien np = regexp(); 59385587Sobrien if (rtok != '\0') 59485587Sobrien FATAL("syntax error in regular expression %s at %s", lastre, prestr); 59585587Sobrien return(np); 59685587Sobrien} 59785587Sobrien 59885587SobrienNode *regexp(void) /* top-level parse of reg expr */ 59985587Sobrien{ 60085587Sobrien return (alt(concat(primary()))); 60185587Sobrien} 60285587Sobrien 60385587SobrienNode *primary(void) 60485587Sobrien{ 60585587Sobrien Node *np; 60685587Sobrien 60785587Sobrien switch (rtok) { 60885587Sobrien case CHAR: 60985587Sobrien np = op2(CHAR, NIL, itonp(rlxval)); 61085587Sobrien rtok = relex(); 61185587Sobrien return (unary(np)); 61285587Sobrien case ALL: 61385587Sobrien rtok = relex(); 61485587Sobrien return (unary(op2(ALL, NIL, NIL))); 61585587Sobrien case DOT: 61685587Sobrien rtok = relex(); 61785587Sobrien return (unary(op2(DOT, NIL, NIL))); 61885587Sobrien case CCL: 61985587Sobrien np = op2(CCL, NIL, (Node*) cclenter((char *) rlxstr)); 62085587Sobrien rtok = relex(); 62185587Sobrien return (unary(np)); 62285587Sobrien case NCCL: 62385587Sobrien np = op2(NCCL, NIL, (Node *) cclenter((char *) rlxstr)); 62485587Sobrien rtok = relex(); 62585587Sobrien return (unary(np)); 62685587Sobrien case '^': 62785587Sobrien rtok = relex(); 62885587Sobrien return (unary(op2(CHAR, NIL, itonp(HAT)))); 62985587Sobrien case '$': 63085587Sobrien rtok = relex(); 63185587Sobrien return (unary(op2(CHAR, NIL, NIL))); 63285587Sobrien case '(': 63385587Sobrien rtok = relex(); 63485587Sobrien if (rtok == ')') { /* special pleading for () */ 63585587Sobrien rtok = relex(); 63685587Sobrien return unary(op2(CCL, NIL, (Node *) tostring(""))); 63785587Sobrien } 63885587Sobrien np = regexp(); 63985587Sobrien if (rtok == ')') { 64085587Sobrien rtok = relex(); 64185587Sobrien return (unary(np)); 64285587Sobrien } 64385587Sobrien else 64485587Sobrien FATAL("syntax error in regular expression %s at %s", lastre, prestr); 64585587Sobrien default: 64685587Sobrien FATAL("illegal primary in regular expression %s at %s", lastre, prestr); 64785587Sobrien } 64885587Sobrien return 0; /*NOTREACHED*/ 64985587Sobrien} 65085587Sobrien 65185587SobrienNode *concat(Node *np) 65285587Sobrien{ 65385587Sobrien switch (rtok) { 65485587Sobrien case CHAR: case DOT: case ALL: case CCL: case NCCL: case '$': case '(': 65585587Sobrien return (concat(op2(CAT, np, primary()))); 65685587Sobrien } 65785587Sobrien return (np); 65885587Sobrien} 65985587Sobrien 66085587SobrienNode *alt(Node *np) 66185587Sobrien{ 66285587Sobrien if (rtok == OR) { 66385587Sobrien rtok = relex(); 66485587Sobrien return (alt(op2(OR, np, concat(primary())))); 66585587Sobrien } 66685587Sobrien return (np); 66785587Sobrien} 66885587Sobrien 66985587SobrienNode *unary(Node *np) 67085587Sobrien{ 67185587Sobrien switch (rtok) { 67285587Sobrien case STAR: 67385587Sobrien rtok = relex(); 67485587Sobrien return (unary(op2(STAR, np, NIL))); 67585587Sobrien case PLUS: 67685587Sobrien rtok = relex(); 67785587Sobrien return (unary(op2(PLUS, np, NIL))); 67885587Sobrien case QUEST: 67985587Sobrien rtok = relex(); 68085587Sobrien return (unary(op2(QUEST, np, NIL))); 68185587Sobrien default: 68285587Sobrien return (np); 68385587Sobrien } 68485587Sobrien} 68585587Sobrien 68685587Sobrienint relex(void) /* lexical analyzer for reparse */ 68785587Sobrien{ 68885587Sobrien int c, n; 68985587Sobrien int cflag; 69085587Sobrien static uschar *buf = 0; 69185587Sobrien static int bufsz = 100; 69285587Sobrien uschar *bp; 69385587Sobrien 69485587Sobrien switch (c = *prestr++) { 69585587Sobrien case '|': return OR; 69685587Sobrien case '*': return STAR; 69785587Sobrien case '+': return PLUS; 69885587Sobrien case '?': return QUEST; 69985587Sobrien case '.': return DOT; 70085587Sobrien case '\0': prestr--; return '\0'; 70185587Sobrien case '^': 70285587Sobrien case '$': 70385587Sobrien case '(': 70485587Sobrien case ')': 70585587Sobrien return c; 70685587Sobrien case '\\': 70785587Sobrien rlxval = quoted((char **) &prestr); 70885587Sobrien return CHAR; 70985587Sobrien default: 71085587Sobrien rlxval = c; 71185587Sobrien return CHAR; 71285587Sobrien case '[': 71385587Sobrien if (buf == 0 && (buf = (uschar *) malloc(bufsz)) == NULL) 71485587Sobrien FATAL("out of space in reg expr %.10s..", lastre); 71585587Sobrien bp = buf; 71685587Sobrien if (*prestr == '^') { 71785587Sobrien cflag = 1; 71885587Sobrien prestr++; 71985587Sobrien } 72085587Sobrien else 72185587Sobrien cflag = 0; 72285587Sobrien n = 2 * strlen(prestr)+1; 72385587Sobrien if (!adjbuf((char **) &buf, &bufsz, n, n, (char **) &bp, 0)) 72485587Sobrien FATAL("out of space for reg expr %.10s...", lastre); 72585587Sobrien for (; ; ) { 72685587Sobrien if ((c = *prestr++) == '\\') { 72785587Sobrien *bp++ = '\\'; 72885587Sobrien if ((c = *prestr++) == '\0') 72985587Sobrien FATAL("nonterminated character class %.20s...", lastre); 73085587Sobrien *bp++ = c; 73185587Sobrien /* } else if (c == '\n') { */ 73285587Sobrien /* FATAL("newline in character class %.20s...", lastre); */ 73385587Sobrien } else if (c == '\0') { 73485587Sobrien FATAL("nonterminated character class %.20s", lastre); 73585587Sobrien } else if (bp == buf) { /* 1st char is special */ 73685587Sobrien *bp++ = c; 73785587Sobrien } else if (c == ']') { 73885587Sobrien *bp++ = 0; 73985587Sobrien rlxstr = (uschar *) tostring((char *) buf); 74085587Sobrien if (cflag == 0) 74185587Sobrien return CCL; 74285587Sobrien else 74385587Sobrien return NCCL; 74485587Sobrien } else 74585587Sobrien *bp++ = c; 74685587Sobrien } 74785587Sobrien } 74885587Sobrien} 74985587Sobrien 75085587Sobrienint cgoto(fa *f, int s, int c) 75185587Sobrien{ 75285587Sobrien int i, j, k; 75385587Sobrien int *p, *q; 75485587Sobrien 75585587Sobrien if (c < 0 || c > 255) 75685587Sobrien FATAL("can't happen: neg char %d in cgoto", c); 75785587Sobrien while (f->accept >= maxsetvec) { /* guessing here! */ 75885587Sobrien maxsetvec *= 4; 75985587Sobrien setvec = (int *) realloc(setvec, maxsetvec * sizeof(int)); 76085587Sobrien tmpset = (int *) realloc(tmpset, maxsetvec * sizeof(int)); 76185587Sobrien if (setvec == 0 || tmpset == 0) 76285587Sobrien overflo("out of space in cgoto()"); 76385587Sobrien } 76485587Sobrien for (i = 0; i <= f->accept; i++) 76585587Sobrien setvec[i] = 0; 76685587Sobrien setcnt = 0; 76785587Sobrien /* compute positions of gototab[s,c] into setvec */ 76885587Sobrien p = f->posns[s]; 76985587Sobrien for (i = 1; i <= *p; i++) { 77085587Sobrien if ((k = f->re[p[i]].ltype) != FINAL) { 77185587Sobrien if ((k == CHAR && c == ptoi(f->re[p[i]].lval.np)) 77285587Sobrien || (k == DOT && c != 0 && c != HAT) 77385587Sobrien || (k == ALL && c != 0) 77485587Sobrien || (k == CCL && member(c, (char *) f->re[p[i]].lval.up)) 77585587Sobrien || (k == NCCL && !member(c, (char *) f->re[p[i]].lval.up) && c != 0 && c != HAT)) { 77685587Sobrien q = f->re[p[i]].lfollow; 77785587Sobrien for (j = 1; j <= *q; j++) { 77885587Sobrien if (q[j] >= maxsetvec) { 77985587Sobrien maxsetvec *= 4; 78085587Sobrien setvec = (int *) realloc(setvec, maxsetvec * sizeof(int)); 78185587Sobrien tmpset = (int *) realloc(setvec, maxsetvec * sizeof(int)); 78285587Sobrien if (setvec == 0 || tmpset == 0) 78385587Sobrien overflo("cgoto overflow"); 78485587Sobrien } 78585587Sobrien if (setvec[q[j]] == 0) { 78685587Sobrien setcnt++; 78785587Sobrien setvec[q[j]] = 1; 78885587Sobrien } 78985587Sobrien } 79085587Sobrien } 79185587Sobrien } 79285587Sobrien } 79385587Sobrien /* determine if setvec is a previous state */ 79485587Sobrien tmpset[0] = setcnt; 79585587Sobrien j = 1; 79685587Sobrien for (i = f->accept; i >= 0; i--) 79785587Sobrien if (setvec[i]) { 79885587Sobrien tmpset[j++] = i; 79985587Sobrien } 80085587Sobrien /* tmpset == previous state? */ 80185587Sobrien for (i = 1; i <= f->curstat; i++) { 80285587Sobrien p = f->posns[i]; 80385587Sobrien if ((k = tmpset[0]) != p[0]) 80485587Sobrien goto different; 80585587Sobrien for (j = 1; j <= k; j++) 80685587Sobrien if (tmpset[j] != p[j]) 80785587Sobrien goto different; 80885587Sobrien /* setvec is state i */ 80985587Sobrien f->gototab[s][c] = i; 81085587Sobrien return i; 81185587Sobrien different:; 81285587Sobrien } 81385587Sobrien 81485587Sobrien /* add tmpset to current set of states */ 81585587Sobrien if (f->curstat >= NSTATES-1) { 81685587Sobrien f->curstat = 2; 81785587Sobrien f->reset = 1; 81885587Sobrien for (i = 2; i < NSTATES; i++) 81985587Sobrien xfree(f->posns[i]); 82085587Sobrien } else 82185587Sobrien ++(f->curstat); 82285587Sobrien for (i = 0; i < NCHARS; i++) 82385587Sobrien f->gototab[f->curstat][i] = 0; 82485587Sobrien xfree(f->posns[f->curstat]); 82585587Sobrien if ((p = (int *) calloc(1, (setcnt+1)*sizeof(int))) == NULL) 82685587Sobrien overflo("out of space in cgoto"); 82785587Sobrien 82885587Sobrien f->posns[f->curstat] = p; 82985587Sobrien f->gototab[s][c] = f->curstat; 83085587Sobrien for (i = 0; i <= setcnt; i++) 83185587Sobrien p[i] = tmpset[i]; 83285587Sobrien if (setvec[f->accept]) 83385587Sobrien f->out[f->curstat] = 1; 83485587Sobrien else 83585587Sobrien f->out[f->curstat] = 0; 83685587Sobrien return f->curstat; 83785587Sobrien} 83885587Sobrien 83985587Sobrien 84085587Sobrienvoid freefa(fa *f) /* free a finite automaton */ 84185587Sobrien{ 84285587Sobrien int i; 84385587Sobrien 84485587Sobrien if (f == NULL) 84585587Sobrien return; 84685587Sobrien for (i = 0; i <= f->curstat; i++) 84785587Sobrien xfree(f->posns[i]); 84885587Sobrien for (i = 0; i <= f->accept; i++) { 84985587Sobrien xfree(f->re[i].lfollow); 85085587Sobrien if (f->re[i].ltype == CCL || f->re[i].ltype == NCCL) 85185587Sobrien xfree((f->re[i].lval.np)); 85285587Sobrien } 85385587Sobrien xfree(f->restr); 85485587Sobrien xfree(f); 85585587Sobrien} 856