1*3e12c5d1SDavid du Colombier #include <u.h> 2*3e12c5d1SDavid du Colombier #include <libc.h> 3*3e12c5d1SDavid du Colombier #include "regexp.h" 4*3e12c5d1SDavid du Colombier #include "regcomp.h" 5*3e12c5d1SDavid du Colombier 6*3e12c5d1SDavid du Colombier static Resublist sempty; /* empty set of matches */ 7*3e12c5d1SDavid du Colombier 8*3e12c5d1SDavid du Colombier /* 9*3e12c5d1SDavid du Colombier * return 0 if no match 10*3e12c5d1SDavid du Colombier * >0 if a match 11*3e12c5d1SDavid du Colombier * <0 if we ran out of _relist space 12*3e12c5d1SDavid du Colombier */ 13*3e12c5d1SDavid du Colombier static int 14*3e12c5d1SDavid du Colombier rregexec1(Reprog *progp, /* program to run */ 15*3e12c5d1SDavid du Colombier Rune *bol, /* string to run machine on */ 16*3e12c5d1SDavid du Colombier Resub *mp, /* subexpression elements */ 17*3e12c5d1SDavid du Colombier int ms, /* number of elements at mp */ 18*3e12c5d1SDavid du Colombier Rune *starts, 19*3e12c5d1SDavid du Colombier Rune *eol, 20*3e12c5d1SDavid du Colombier Rune startchar) 21*3e12c5d1SDavid du Colombier { 22*3e12c5d1SDavid du Colombier int flag=0; 23*3e12c5d1SDavid du Colombier Reinst *inst; 24*3e12c5d1SDavid du Colombier Relist *tlp; 25*3e12c5d1SDavid du Colombier Rune *s; 26*3e12c5d1SDavid du Colombier int i, checkstart; 27*3e12c5d1SDavid du Colombier Rune r, *rp, *ep; 28*3e12c5d1SDavid du Colombier Relist* tl; /* This list, next list */ 29*3e12c5d1SDavid du Colombier Relist* nl; 30*3e12c5d1SDavid du Colombier Relist* tle; /* ends of this and next list */ 31*3e12c5d1SDavid du Colombier Relist* nle; 32*3e12c5d1SDavid du Colombier int match; 33*3e12c5d1SDavid du Colombier 34*3e12c5d1SDavid du Colombier match = 0; 35*3e12c5d1SDavid du Colombier checkstart = startchar; 36*3e12c5d1SDavid du Colombier sempty.m[0].rsp = 0; 37*3e12c5d1SDavid du Colombier if(mp!=0) 38*3e12c5d1SDavid du Colombier for(i=0; i<ms; i++) 39*3e12c5d1SDavid du Colombier mp[i].rsp = mp[i].rep = 0; 40*3e12c5d1SDavid du Colombier _relist[0][0].inst = _relist[1][0].inst = 0; 41*3e12c5d1SDavid du Colombier 42*3e12c5d1SDavid du Colombier /* Execute machine once for each character, including terminal NUL */ 43*3e12c5d1SDavid du Colombier s = starts; 44*3e12c5d1SDavid du Colombier do{ 45*3e12c5d1SDavid du Colombier r = *s; 46*3e12c5d1SDavid du Colombier 47*3e12c5d1SDavid du Colombier /* fast check for first char */ 48*3e12c5d1SDavid du Colombier if(checkstart && r!=startchar){ 49*3e12c5d1SDavid du Colombier s++; 50*3e12c5d1SDavid du Colombier continue; 51*3e12c5d1SDavid du Colombier } 52*3e12c5d1SDavid du Colombier 53*3e12c5d1SDavid du Colombier /* switch run lists */ 54*3e12c5d1SDavid du Colombier tl = _relist[flag]; 55*3e12c5d1SDavid du Colombier tle = _reliste[flag]; 56*3e12c5d1SDavid du Colombier nl = _relist[flag^=1]; 57*3e12c5d1SDavid du Colombier nle = _reliste[flag]; 58*3e12c5d1SDavid du Colombier nl->inst = 0; 59*3e12c5d1SDavid du Colombier 60*3e12c5d1SDavid du Colombier /* Add first instruction to current list */ 61*3e12c5d1SDavid du Colombier sempty.m[0].rsp = s; 62*3e12c5d1SDavid du Colombier _renewthread(tl, progp->startinst, &sempty); 63*3e12c5d1SDavid du Colombier 64*3e12c5d1SDavid du Colombier /* Execute machine until current list is empty */ 65*3e12c5d1SDavid du Colombier for(tlp=tl; tlp->inst; tlp++){ /* assignment = */ 66*3e12c5d1SDavid du Colombier if(s == eol) 67*3e12c5d1SDavid du Colombier break; 68*3e12c5d1SDavid du Colombier 69*3e12c5d1SDavid du Colombier for(inst=tlp->inst; ; inst = inst->next){ 70*3e12c5d1SDavid du Colombier switch(inst->type){ 71*3e12c5d1SDavid du Colombier case RUNE: /* regular character */ 72*3e12c5d1SDavid du Colombier if(inst->r == r) 73*3e12c5d1SDavid du Colombier if(_renewthread(nl, inst->next, &tlp->se)==nle) 74*3e12c5d1SDavid du Colombier return -1; 75*3e12c5d1SDavid du Colombier break; 76*3e12c5d1SDavid du Colombier case LBRA: 77*3e12c5d1SDavid du Colombier tlp->se.m[inst->subid].rsp = s; 78*3e12c5d1SDavid du Colombier continue; 79*3e12c5d1SDavid du Colombier case RBRA: 80*3e12c5d1SDavid du Colombier tlp->se.m[inst->subid].rep = s; 81*3e12c5d1SDavid du Colombier continue; 82*3e12c5d1SDavid du Colombier case ANY: 83*3e12c5d1SDavid du Colombier if(r != '\n') 84*3e12c5d1SDavid du Colombier if(_renewthread(nl, inst->next, &tlp->se)==nle) 85*3e12c5d1SDavid du Colombier return -1; 86*3e12c5d1SDavid du Colombier break; 87*3e12c5d1SDavid du Colombier case ANYNL: 88*3e12c5d1SDavid du Colombier if(_renewthread(nl, inst->next, &tlp->se)==nle) 89*3e12c5d1SDavid du Colombier return -1; 90*3e12c5d1SDavid du Colombier break; 91*3e12c5d1SDavid du Colombier case BOL: 92*3e12c5d1SDavid du Colombier if(s == bol || *(s-1) == '\n') 93*3e12c5d1SDavid du Colombier continue; 94*3e12c5d1SDavid du Colombier break; 95*3e12c5d1SDavid du Colombier case EOL: 96*3e12c5d1SDavid du Colombier if(r == 0 || r == '\n') 97*3e12c5d1SDavid du Colombier continue; 98*3e12c5d1SDavid du Colombier break; 99*3e12c5d1SDavid du Colombier case CCLASS: 100*3e12c5d1SDavid du Colombier ep = inst->cp->end; 101*3e12c5d1SDavid du Colombier for(rp = inst->cp->spans; rp < ep; rp += 2) 102*3e12c5d1SDavid du Colombier if(r >= rp[0] && r <= rp[1]){ 103*3e12c5d1SDavid du Colombier if(_renewthread(nl, inst->next, &tlp->se)==nle) 104*3e12c5d1SDavid du Colombier return -1; 105*3e12c5d1SDavid du Colombier break; 106*3e12c5d1SDavid du Colombier } 107*3e12c5d1SDavid du Colombier break; 108*3e12c5d1SDavid du Colombier case NCCLASS: 109*3e12c5d1SDavid du Colombier ep = inst->cp->end; 110*3e12c5d1SDavid du Colombier for(rp = inst->cp->spans; rp < ep; rp += 2) 111*3e12c5d1SDavid du Colombier if(r >= rp[0] && r <= rp[1]) 112*3e12c5d1SDavid du Colombier break; 113*3e12c5d1SDavid du Colombier if(rp == ep) 114*3e12c5d1SDavid du Colombier if(_renewthread(nl, inst->next, &tlp->se)==nle) 115*3e12c5d1SDavid du Colombier return -1; 116*3e12c5d1SDavid du Colombier break; 117*3e12c5d1SDavid du Colombier case OR: 118*3e12c5d1SDavid du Colombier /* evaluate right choice later */ 119*3e12c5d1SDavid du Colombier if(_renewthread(tlp, inst->right, &tlp->se) == tle) 120*3e12c5d1SDavid du Colombier return -1; 121*3e12c5d1SDavid du Colombier /* efficiency: advance and re-evaluate */ 122*3e12c5d1SDavid du Colombier continue; 123*3e12c5d1SDavid du Colombier case END: /* Match! */ 124*3e12c5d1SDavid du Colombier match = 1; 125*3e12c5d1SDavid du Colombier tlp->se.m[0].rep = s; 126*3e12c5d1SDavid du Colombier if(mp != 0) 127*3e12c5d1SDavid du Colombier _renewmatch(mp, ms, &tlp->se); 128*3e12c5d1SDavid du Colombier break; 129*3e12c5d1SDavid du Colombier } 130*3e12c5d1SDavid du Colombier break; 131*3e12c5d1SDavid du Colombier } 132*3e12c5d1SDavid du Colombier } 133*3e12c5d1SDavid du Colombier checkstart = startchar && nl->inst==0; 134*3e12c5d1SDavid du Colombier s++; 135*3e12c5d1SDavid du Colombier }while(r); 136*3e12c5d1SDavid du Colombier return match; 137*3e12c5d1SDavid du Colombier } 138*3e12c5d1SDavid du Colombier 139*3e12c5d1SDavid du Colombier extern int 140*3e12c5d1SDavid du Colombier rregexec(Reprog *progp, /* program to run */ 141*3e12c5d1SDavid du Colombier Rune *bol, /* string to run machine on */ 142*3e12c5d1SDavid du Colombier Resub *mp, /* subexpression elements */ 143*3e12c5d1SDavid du Colombier int ms) /* number of elements at mp */ 144*3e12c5d1SDavid du Colombier { 145*3e12c5d1SDavid du Colombier Rune *starts; /* where to start match */ 146*3e12c5d1SDavid du Colombier Rune *eol; /* where to end match */ 147*3e12c5d1SDavid du Colombier Rune startchar; 148*3e12c5d1SDavid du Colombier int rv; 149*3e12c5d1SDavid du Colombier 150*3e12c5d1SDavid du Colombier /* 151*3e12c5d1SDavid du Colombier * use user-specified starting/ending location if specified 152*3e12c5d1SDavid du Colombier */ 153*3e12c5d1SDavid du Colombier starts = bol; 154*3e12c5d1SDavid du Colombier eol = 0; 155*3e12c5d1SDavid du Colombier if(mp && ms>0){ 156*3e12c5d1SDavid du Colombier if(mp->rsp) 157*3e12c5d1SDavid du Colombier starts = mp->rsp; 158*3e12c5d1SDavid du Colombier if(mp->rep) 159*3e12c5d1SDavid du Colombier eol = mp->rep; 160*3e12c5d1SDavid du Colombier } 161*3e12c5d1SDavid du Colombier startchar = progp->startinst->type == RUNE ? progp->startinst->r : 0; 162*3e12c5d1SDavid du Colombier 163*3e12c5d1SDavid du Colombier /* keep trying till we have enough list space to terminate */ 164*3e12c5d1SDavid du Colombier for(;;){ 165*3e12c5d1SDavid du Colombier if(_relist[0] == 0){ 166*3e12c5d1SDavid du Colombier _relist[0] = malloc(2*_relistsize*sizeof(Relist)); 167*3e12c5d1SDavid du Colombier _relist[1] = _relist[0] + _relistsize; 168*3e12c5d1SDavid du Colombier _reliste[0] = _relist[0] + _relistsize - 1; 169*3e12c5d1SDavid du Colombier _reliste[1] = _relist[1] + _relistsize - 1; 170*3e12c5d1SDavid du Colombier if(_relist[0] == 0) 171*3e12c5d1SDavid du Colombier regerror("_relist overflow"); 172*3e12c5d1SDavid du Colombier } 173*3e12c5d1SDavid du Colombier rv = rregexec1(progp, bol, mp, ms, starts, eol, startchar); 174*3e12c5d1SDavid du Colombier if(rv >= 0) 175*3e12c5d1SDavid du Colombier return rv; 176*3e12c5d1SDavid du Colombier free(_relist[0]); 177*3e12c5d1SDavid du Colombier _relist[0] = 0; 178*3e12c5d1SDavid du Colombier _relistsize += LISTINCREMENT; 179*3e12c5d1SDavid du Colombier } 180*3e12c5d1SDavid du Colombier return -1; 181*3e12c5d1SDavid du Colombier } 182