-
-/*
- - zapmem - initialize the retry memory of a subtree to zeros
- ^ static VOID zapmem(struct vars *, struct subre *);
- */
-static VOID
-zapmem(v, t)
-struct vars *v;
-struct subre *t;
-{
- if (t == NULL)
- return;
-
- assert(v->mem != NULL);
- v->mem[t->retry] = 0;
- if (t->op == '(') {
- assert(t->subno > 0);
- v->pmatch[t->subno].rm_so = -1;
- v->pmatch[t->subno].rm_eo = -1;
- }
-
- if (t->left != NULL)
- zapmem(v, t->left);
- if (t->right != NULL)
- zapmem(v, t->right);
-}
-
-/*
- - subset - set any subexpression relevant to a successful subre
- ^ static VOID subset(struct vars *, struct subre *, chr *, chr *);
- */
-static VOID
-subset(v, sub, begin, end)
-struct vars *v;
-struct subre *sub;
-chr *begin;
-chr *end;
-{
- int n = sub->subno;
-
- assert(n > 0);
- if ((size_t)n >= v->nmatch)
- return;
-
- MDEBUG(("setting %d\n", n));
- v->pmatch[n].rm_so = OFF(begin);
- v->pmatch[n].rm_eo = OFF(end);
-}
-
-/*
- - dissect - determine subexpression matches (uncomplicated case)
- ^ static int dissect(struct vars *, struct subre *, chr *, chr *);
- */
-static int /* regexec return code */
-dissect(v, t, begin, end)
-struct vars *v;
-struct subre *t;
-chr *begin; /* beginning of relevant substring */
-chr *end; /* end of same */
-{
- assert(t != NULL);
- MDEBUG(("dissect %ld-%ld\n", LOFF(begin), LOFF(end)));
-
- switch (t->op) {
- case '=': /* terminal node */
- assert(t->left == NULL && t->right == NULL);
- return REG_OKAY; /* no action, parent did the work */
- break;
- case '|': /* alternation */
- assert(t->left != NULL);
- return altdissect(v, t, begin, end);
- break;
- case 'b': /* back ref -- shouldn't be calling us! */
- return REG_ASSERT;
- break;
- case '.': /* concatenation */
- assert(t->left != NULL && t->right != NULL);
- return condissect(v, t, begin, end);
- break;
- case '(': /* capturing */
- assert(t->left != NULL && t->right == NULL);
- assert(t->subno > 0);
- subset(v, t, begin, end);
- return dissect(v, t->left, begin, end);
- break;
- default:
- return REG_ASSERT;
- break;
- }
-}
-
-/*
- - condissect - determine concatenation subexpression matches (uncomplicated)
- ^ static int condissect(struct vars *, struct subre *, chr *, chr *);
- */
-static int /* regexec return code */
-condissect(v, t, begin, end)
-struct vars *v;
-struct subre *t;
-chr *begin; /* beginning of relevant substring */
-chr *end; /* end of same */
-{
- struct dfa *d;
- struct dfa *d2;
- chr *mid;
- int i;
- int shorter = (t->left->flags&SHORTER) ? 1 : 0;
- chr *stop = (shorter) ? end : begin;
-
- assert(t->op == '.');
- assert(t->left != NULL && t->left->cnfa.nstates > 0);
- assert(t->right != NULL && t->right->cnfa.nstates > 0);
-
- d = newdfa(v, &t->left->cnfa, &v->g->cmap, &v->dfa1);
- NOERR();
- d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, &v->dfa2);
- if (ISERR()) {
- assert(d2 == NULL);
- freedfa(d);
- return v->err;
- }
-
- /* pick a tentative midpoint */
- if (shorter)
- mid = shortest(v, d, begin, begin, end, (chr **)NULL,
- (int *)NULL);
- else
- mid = longest(v, d, begin, end, (int *)NULL);
- if (mid == NULL) {
- freedfa(d);
- freedfa(d2);
- return REG_ASSERT;
- }
- MDEBUG(("tentative midpoint %ld\n", LOFF(mid)));
-
- /* iterate until satisfaction or failure */
- while (longest(v, d2, mid, end, (int *)NULL) != end) {
- /* that midpoint didn't work, find a new one */
- if (mid == stop) {
- /* all possibilities exhausted! */
- MDEBUG(("no midpoint!\n"));
- freedfa(d);
- freedfa(d2);
- return REG_ASSERT;
- }
- if (shorter)
- mid = shortest(v, d, begin, mid+1, end, (chr **)NULL,
- (int *)NULL);
- else
- mid = longest(v, d, begin, mid-1, (int *)NULL);
- if (mid == NULL) {
- /* failed to find a new one! */
- MDEBUG(("failed midpoint!\n"));
- freedfa(d);
- freedfa(d2);
- return REG_ASSERT;
- }
- MDEBUG(("new midpoint %ld\n", LOFF(mid)));
- }
-
- /* satisfaction */
- MDEBUG(("successful\n"));
- freedfa(d);
- freedfa(d2);
- i = dissect(v, t->left, begin, mid);
- if (i != REG_OKAY)
- return i;
- return dissect(v, t->right, mid, end);
-}
-
-/*
- - altdissect - determine alternative subexpression matches (uncomplicated)
- ^ static int altdissect(struct vars *, struct subre *, chr *, chr *);
- */
-static int /* regexec return code */
-altdissect(v, t, begin, end)
-struct vars *v;
-struct subre *t;
-chr *begin; /* beginning of relevant substring */
-chr *end; /* end of same */
-{
- struct dfa *d;
- int i;
-
- assert(t != NULL);
- assert(t->op == '|');
-
- for (i = 0; t != NULL; t = t->right, i++) {
- MDEBUG(("trying %dth\n", i));
- assert(t->left != NULL && t->left->cnfa.nstates > 0);
- d = newdfa(v, &t->left->cnfa, &v->g->cmap, &v->dfa1);
- if (ISERR())
- return v->err;
- if (longest(v, d, begin, end, (int *)NULL) == end) {
- MDEBUG(("success\n"));
- freedfa(d);
- return dissect(v, t->left, begin, end);
- }
- freedfa(d);
- }
- return REG_ASSERT; /* none of them matched?!? */
-}
-
-/*
- - cdissect - determine subexpression matches (with complications)
- * The retry memory stores the offset of the trial midpoint from begin,
- * plus 1 so that 0 uniquely means "clean slate".
- ^ static int cdissect(struct vars *, struct subre *, chr *, chr *);
- */
-static int /* regexec return code */
-cdissect(v, t, begin, end)
-struct vars *v;
-struct subre *t;
-chr *begin; /* beginning of relevant substring */
-chr *end; /* end of same */
-{
- int er;
-
- assert(t != NULL);
- MDEBUG(("cdissect %ld-%ld %c\n", LOFF(begin), LOFF(end), t->op));
-
- switch (t->op) {
- case '=': /* terminal node */
- assert(t->left == NULL && t->right == NULL);
- return REG_OKAY; /* no action, parent did the work */
- break;
- case '|': /* alternation */
- assert(t->left != NULL);
- return caltdissect(v, t, begin, end);
- break;
- case 'b': /* back ref -- shouldn't be calling us! */
- assert(t->left == NULL && t->right == NULL);
- return cbrdissect(v, t, begin, end);
- break;
- case '.': /* concatenation */
- assert(t->left != NULL && t->right != NULL);
- return ccondissect(v, t, begin, end);
- break;
- case '(': /* capturing */
- assert(t->left != NULL && t->right == NULL);
- assert(t->subno > 0);
- er = cdissect(v, t->left, begin, end);
- if (er == REG_OKAY)
- subset(v, t, begin, end);
- return er;
- break;
- default:
- return REG_ASSERT;
- break;
- }
-}
-
-/*
- - ccondissect - concatenation subexpression matches (with complications)
- * The retry memory stores the offset of the trial midpoint from begin,
- * plus 1 so that 0 uniquely means "clean slate".
- ^ static int ccondissect(struct vars *, struct subre *, chr *, chr *);
- */
-static int /* regexec return code */
-ccondissect(v, t, begin, end)
-struct vars *v;
-struct subre *t;
-chr *begin; /* beginning of relevant substring */
-chr *end; /* end of same */
-{
- struct dfa *d;
- struct dfa *d2;
- chr *mid;
- int er;
-
- assert(t->op == '.');
- assert(t->left != NULL && t->left->cnfa.nstates > 0);
- assert(t->right != NULL && t->right->cnfa.nstates > 0);
-
- if (t->left->flags&SHORTER) /* reverse scan */
- return crevdissect(v, t, begin, end);
-
- d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC);
- if (ISERR())
- return v->err;
- d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, DOMALLOC);
- if (ISERR()) {
- freedfa(d);
- return v->err;
- }
- MDEBUG(("cconcat %d\n", t->retry));
-
- /* pick a tentative midpoint */
- if (v->mem[t->retry] == 0) {
- mid = longest(v, d, begin, end, (int *)NULL);
- if (mid == NULL) {
- freedfa(d);
- freedfa(d2);
- return REG_NOMATCH;
- }
- MDEBUG(("tentative midpoint %ld\n", LOFF(mid)));
- v->mem[t->retry] = (mid - begin) + 1;
- } else {
- mid = begin + (v->mem[t->retry] - 1);
- MDEBUG(("working midpoint %ld\n", LOFF(mid)));
- }
-
- /* iterate until satisfaction or failure */
- for (;;) {
- /* try this midpoint on for size */
- er = cdissect(v, t->left, begin, mid);
- if (er == REG_OKAY &&
- longest(v, d2, mid, end, (int *)NULL) == end &&
- (er = cdissect(v, t->right, mid, end)) ==
- REG_OKAY)
- break; /* NOTE BREAK OUT */
- if (er != REG_OKAY && er != REG_NOMATCH) {
- freedfa(d);
- freedfa(d2);
- return er;
- }
-
- /* that midpoint didn't work, find a new one */
- if (mid == begin) {
- /* all possibilities exhausted */
- MDEBUG(("%d no midpoint\n", t->retry));
- freedfa(d);
- freedfa(d2);
- return REG_NOMATCH;
- }
- mid = longest(v, d, begin, mid-1, (int *)NULL);
- if (mid == NULL) {
- /* failed to find a new one */
- MDEBUG(("%d failed midpoint\n", t->retry));
- freedfa(d);
- freedfa(d2);
- return REG_NOMATCH;
- }
- MDEBUG(("%d: new midpoint %ld\n", t->retry, LOFF(mid)));
- v->mem[t->retry] = (mid - begin) + 1;
- zapmem(v, t->left);
- zapmem(v, t->right);
- }
-
- /* satisfaction */
- MDEBUG(("successful\n"));
- freedfa(d);
- freedfa(d2);
- return REG_OKAY;
-}
-
-/*
- - crevdissect - determine backref shortest-first subexpression matches
- * The retry memory stores the offset of the trial midpoint from begin,
- * plus 1 so that 0 uniquely means "clean slate".
- ^ static int crevdissect(struct vars *, struct subre *, chr *, chr *);
- */
-static int /* regexec return code */
-crevdissect(v, t, begin, end)
-struct vars *v;
-struct subre *t;
-chr *begin; /* beginning of relevant substring */
-chr *end; /* end of same */
-{
- struct dfa *d;
- struct dfa *d2;
- chr *mid;
- int er;
-
- assert(t->op == '.');
- assert(t->left != NULL && t->left->cnfa.nstates > 0);
- assert(t->right != NULL && t->right->cnfa.nstates > 0);
- assert(t->left->flags&SHORTER);
-
- /* concatenation -- need to split the substring between parts */
- d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC);
- if (ISERR())
- return v->err;
- d2 = newdfa(v, &t->right->cnfa, &v->g->cmap, DOMALLOC);
- if (ISERR()) {
- freedfa(d);
- return v->err;
- }
- MDEBUG(("crev %d\n", t->retry));
-
- /* pick a tentative midpoint */
- if (v->mem[t->retry] == 0) {
- mid = shortest(v, d, begin, begin, end, (chr **)NULL, (int *)NULL);
- if (mid == NULL) {
- freedfa(d);
- freedfa(d2);
- return REG_NOMATCH;
- }
- MDEBUG(("tentative midpoint %ld\n", LOFF(mid)));
- v->mem[t->retry] = (mid - begin) + 1;
- } else {
- mid = begin + (v->mem[t->retry] - 1);
- MDEBUG(("working midpoint %ld\n", LOFF(mid)));
- }
-
- /* iterate until satisfaction or failure */
- for (;;) {
- /* try this midpoint on for size */
- er = cdissect(v, t->left, begin, mid);
- if (er == REG_OKAY &&
- longest(v, d2, mid, end, (int *)NULL) == end &&
- (er = cdissect(v, t->right, mid, end)) ==
- REG_OKAY)
- break; /* NOTE BREAK OUT */
- if (er != REG_OKAY && er != REG_NOMATCH) {
- freedfa(d);
- freedfa(d2);
- return er;
- }
-
- /* that midpoint didn't work, find a new one */
- if (mid == end) {
- /* all possibilities exhausted */
- MDEBUG(("%d no midpoint\n", t->retry));
- freedfa(d);
- freedfa(d2);
- return REG_NOMATCH;
- }
- mid = shortest(v, d, begin, mid+1, end, (chr **)NULL, (int *)NULL);
- if (mid == NULL) {
- /* failed to find a new one */
- MDEBUG(("%d failed midpoint\n", t->retry));
- freedfa(d);
- freedfa(d2);
- return REG_NOMATCH;
- }
- MDEBUG(("%d: new midpoint %ld\n", t->retry, LOFF(mid)));
- v->mem[t->retry] = (mid - begin) + 1;
- zapmem(v, t->left);
- zapmem(v, t->right);
- }
-
- /* satisfaction */
- MDEBUG(("successful\n"));
- freedfa(d);
- freedfa(d2);
- return REG_OKAY;
-}
-
-/*
- - cbrdissect - determine backref subexpression matches
- ^ static int cbrdissect(struct vars *, struct subre *, chr *, chr *);
- */
-static int /* regexec return code */
-cbrdissect(v, t, begin, end)
-struct vars *v;
-struct subre *t;
-chr *begin; /* beginning of relevant substring */
-chr *end; /* end of same */
-{
- int i;
- int n = t->subno;
- size_t len;
- chr *paren;
- chr *p;
- chr *stop;
- int min = t->min;
- int max = t->max;
-
- assert(t != NULL);
- assert(t->op == 'b');
- assert(n >= 0);
- assert((size_t)n < v->nmatch);
-
- MDEBUG(("cbackref n%d %d{%d-%d}\n", t->retry, n, min, max));
-
- if (v->pmatch[n].rm_so == -1)
- return REG_NOMATCH;
- paren = v->start + v->pmatch[n].rm_so;
- len = v->pmatch[n].rm_eo - v->pmatch[n].rm_so;
-
- /* no room to maneuver -- retries are pointless */
- if (v->mem[t->retry])
- return REG_NOMATCH;
- v->mem[t->retry] = 1;
-
- /* special-case zero-length string */
- if (len == 0) {
- if (begin == end)
- return REG_OKAY;
- return REG_NOMATCH;
- }
-
- /* and too-short string */
- assert(end >= begin);
- if ((size_t)(end - begin) < len)
- return REG_NOMATCH;
- stop = end - len;
-
- /* count occurrences */
- i = 0;
- for (p = begin; p <= stop && (i < max || max == INFINITY); p += len) {
- if ((*v->g->compare)(paren, p, len) != 0)
- break;
- i++;
- }
- MDEBUG(("cbackref found %d\n", i));
-
- /* and sort it out */
- if (p != end) /* didn't consume all of it */
- return REG_NOMATCH;
- if (min <= i && (i <= max || max == INFINITY))
- return REG_OKAY;
- return REG_NOMATCH; /* out of range */
-}
-
-/*
- - caltdissect - determine alternative subexpression matches (w. complications)
- ^ static int caltdissect(struct vars *, struct subre *, chr *, chr *);
- */
-static int /* regexec return code */
-caltdissect(v, t, begin, end)
-struct vars *v;
-struct subre *t;
-chr *begin; /* beginning of relevant substring */
-chr *end; /* end of same */
-{
- struct dfa *d;
- int er;
-# define UNTRIED 0 /* not yet tried at all */
-# define TRYING 1 /* top matched, trying submatches */
-# define TRIED 2 /* top didn't match or submatches exhausted */
-
- if (t == NULL)
- return REG_NOMATCH;
- assert(t->op == '|');
- if (v->mem[t->retry] == TRIED)
- return caltdissect(v, t->right, begin, end);
-
- MDEBUG(("calt n%d\n", t->retry));
- assert(t->left != NULL);
-
- if (v->mem[t->retry] == UNTRIED) {
- d = newdfa(v, &t->left->cnfa, &v->g->cmap, DOMALLOC);
- if (ISERR())
- return v->err;
- if (longest(v, d, begin, end, (int *)NULL) != end) {
- freedfa(d);
- v->mem[t->retry] = TRIED;
- return caltdissect(v, t->right, begin, end);
- }
- freedfa(d);
- MDEBUG(("calt matched\n"));
- v->mem[t->retry] = TRYING;
- }
-
- er = cdissect(v, t->left, begin, end);
- if (er != REG_NOMATCH)
- return er;
-
- v->mem[t->retry] = TRIED;
- return caltdissect(v, t->right, begin, end);
-}
-
-
-
-#include "rege_dfa.c"