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-rw-r--r--generic/regcomp.c75
1 files changed, 46 insertions, 29 deletions
diff --git a/generic/regcomp.c b/generic/regcomp.c
index b8a5a87..11a389a 100644
--- a/generic/regcomp.c
+++ b/generic/regcomp.c
@@ -83,9 +83,6 @@ static int lexdigits(struct vars *, int, int, int);
static int brenext(struct vars *, pchr);
static void skip(struct vars *);
static chr newline(NOPARMS);
-#ifdef REG_DEBUG
-static const chr *ch(NOPARMS);
-#endif
static chr chrnamed(struct vars *, const chr *, const chr *, pchr);
/* === regc_color.c === */
static void initcm(struct vars *, struct colormap *);
@@ -165,7 +162,7 @@ static void dumparc(struct arc *, struct state *, FILE *);
#endif
static void dumpcnfa(struct cnfa *, FILE *);
#ifdef REG_DEBUG
-static void dumpcstate(int, struct carc *, struct cnfa *, FILE *);
+static void dumpcstate(int, struct cnfa *, FILE *);
#endif
/* === regc_cvec.c === */
static struct cvec *clearcvec(struct cvec *);
@@ -210,7 +207,7 @@ struct vars {
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 */
+ int ntree; /* number of tree nodes, plus one */
struct cvec *cv; /* interface cvec */
struct cvec *cv2; /* utility cvec */
struct subre *lacons; /* lookahead-constraint vector */
@@ -223,13 +220,13 @@ struct vars {
#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)))
+#define VERR(vv,e) ((vv)->nexttype = EOS, \
+ (vv)->err = ((vv)->err ? (vv)->err : (e)))
#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 INSIST(c, e) do { if (!(c)) ERR(e); } while (0) /* error if c false */
#define NOTE(b) (v->re->re_info |= (b)) /* note visible condition */
#define EMPTYARC(x, y) newarc(v->nfa, EMPTY, 0, x, y)
@@ -258,12 +255,14 @@ struct vars {
((a)->type == PLAIN || (a)->type == AHEAD || (a)->type == BEHIND)
/* static function list */
-static struct fns functions = {
+static const struct fns functions = {
rfree, /* regfree insides */
};
/*
- compile - compile regular expression
+ * Note: on failure, no resources remain allocated, so regfree()
+ * need not be applied to re.
^ int compile(regex_t *, const chr *, size_t, int);
*/
int
@@ -1788,7 +1787,8 @@ freesrnode(
}
sr->flags = 0;
- if (v != NULL) {
+ if (v != NULL && v->treechain != NULL) {
+ /* we're still parsing, maybe we can reuse the subre */
sr->left = v->treefree;
v->treefree = sr;
} else {
@@ -1841,6 +1841,19 @@ numst(
/*
- markst - mark tree nodes as INUSE
+ * Note: this is a great deal more subtle than it looks. During initial
+ * parsing of a regex, all subres are linked into the treechain list;
+ * discarded ones are also linked into the treefree list for possible reuse.
+ * After we are done creating all subres required for a regex, we run markst()
+ * then cleanst(), which results in discarding all subres not reachable from
+ * v->tree. We then clear v->treechain, indicating that subres must be found
+ * by descending from v->tree. This changes the behavior of freesubre(): it
+ * will henceforth FREE() unwanted subres rather than sticking them into the
+ * treefree list. (Doing that any earlier would result in dangling links in
+ * the treechain list.) This all means that freev() will clean up correctly
+ * if invoked before or after markst()+cleanst(); but it would not work if
+ * called partway through this state conversion, so we mustn't error out
+ * in or between these two functions.
^ static void markst(struct subre *);
*/
static void
@@ -1947,24 +1960,26 @@ newlacon(
struct state *end,
int pos)
{
- struct subre *sub;
int n;
+ struct subre *newlacons;
+ struct subre *sub;
if (v->nlacons == 0) {
- v->lacons = (struct subre *) MALLOC(2 * sizeof(struct subre));
n = 1; /* skip 0th */
- v->nlacons = 2;
+ newlacons = (struct subre *) MALLOC(2 * sizeof(struct subre));
} else {
- v->lacons = (struct subre *) REALLOC(v->lacons,
- (v->nlacons+1)*sizeof(struct subre));
- n = v->nlacons++;
+ n = v->nlacons;
+ newlacons = (struct subre *) REALLOC(v->lacons,
+ (n + 1) * sizeof(struct subre));
}
- if (v->lacons == NULL) {
+ if (newlacons == NULL) {
ERR(REG_ESPACE);
return 0;
}
+ v->lacons = newlacons;
+ v->nlacons = n + 1;
sub = &v->lacons[n];
sub->begin = begin;
sub->end = end;
@@ -2012,18 +2027,20 @@ rfree(
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(NULL, g->tree);
- }
- if (g->lacons != NULL) {
- freelacons(g->lacons, g->nlacons);
- }
- if (!NULLCNFA(g->search)) {
- freecnfa(&g->search);
+ if (g != NULL) {
+ g->magic = 0;
+ freecm(&g->cmap);
+ if (g->tree != NULL) {
+ freesubre(NULL, g->tree);
+ }
+ if (g->lacons != NULL) {
+ freelacons(g->lacons, g->nlacons);
+ }
+ if (!NULLCNFA(g->search)) {
+ freecnfa(&g->search);
+ }
+ FREE(g);
}
- FREE(g);
}
/*
@@ -2055,7 +2072,7 @@ dump(
fprintf(f, "\n\n\n========= DUMP ==========\n");
fprintf(f, "nsub %d, info 0%lo, csize %d, ntree %d\n",
- re->re_nsub, re->re_info, re->re_csize, g->ntree);
+ (int) re->re_nsub, re->re_info, re->re_csize, g->ntree);
dumpcolors(&g->cmap, f);
if (!NULLCNFA(g->search)) {