compute the length of the subject string only once in match()

src/vmod_re2.c

@@ -151,7 +151,7 @@ VCL_BOOL
 vmod_regex_match(const struct vrt_ctx *ctx, struct vmod_re2_regex *re,
 		 VCL_STRING subject)
 {
-	int match = 0, ngroups = 0;
+	int match = 0, ngroups = 0, len;
 	const char *err;
 	char *text = (void *) subject;
 	void *group = NULL;
@@ -165,9 +165,10 @@ vmod_regex_match(const struct vrt_ctx *ctx, struct vmod_re2_regex *re,
 
 	AZ(pthread_setspecific(re->matchk, match_failed));
 
+	len = strlen(subject);
 	if (! re->never_capture) {
 		ngroups = re->ngroups + 1;
-		if ((text = WS_Copy(ctx->ws, subject, -1)) == NULL) {
+		if ((text = WS_Copy(ctx->ws, subject, len + 1)) == NULL) {
 			VERR(ctx, ERR_PREFIX "insufficient workspace to copy "
 			     "subject", re->vcl_name, subject);
 			return 0;
@@ -181,7 +182,7 @@ vmod_regex_match(const struct vrt_ctx *ctx, struct vmod_re2_regex *re,
 		}
 	}
 
-	if ((err = vre2_match(re->vre2, text, &match, ngroups, group))
+	if ((err = vre2_match(re->vre2, text, len, &match, ngroups, group))
 	    != NULL) {
 		VERR(ctx, ERR_PREFIX "%s", re->vcl_name, subject, err);
 		WS_Reset(ctx->ws, text);

src/vre2/vre2.cpp

@@ -56,10 +56,10 @@ vre2::~vre2() {
 }
 
 inline bool
-vre2::match(const char *subject, const int ngroups, StringPiece* groups) const
+vre2::match(const char *subject, const size_t len, const int ngroups,
+    StringPiece* groups) const
 {
-	return re_->Match(subject, 0, strlen(subject), RE2::UNANCHORED,
-	    groups, ngroups);
+	return re_->Match(subject, 0, len, RE2::UNANCHORED, groups, ngroups);
 }
 
 inline const int
@@ -106,12 +106,12 @@ vre2_matchsz(void)
 }
 
 const char *
-vre2_match(vre2 *vre2, const char * const subject, int * const match,
-    const int ngroups, void * const group)
+vre2_match(vre2 *vre2, const char * const subject, const size_t len,
+    int * const match, const int ngroups, void * const group)
 {
 	try {
 		StringPiece* g = reinterpret_cast<StringPiece *>(group);
-		*match = vre2->match(subject, ngroups, g);
+		*match = vre2->match(subject, len, ngroups, g);
 		return NULL;
 	}
 	CATCHALL

src/vre2/vre2.h

@@ -43,7 +43,8 @@ private:
 public:
 	vre2(const char *pattern, RE2::Options * const opt);
 	virtual ~vre2();
-	bool match(const char *subject, int ngroups, StringPiece* groups) const;
+	bool match(const char *subject, size_t len, int ngroups,
+		   StringPiece* groups) const;
 	const int ngroups() const;
 };
 #else
@@ -65,7 +66,7 @@ extern "C" {
 	const size_t vre2_matchsz(void);
 	const char *vre2_ngroups(vre2 *vre2, int * const ngroups);
 	const char *vre2_match(vre2 *vre2, const char * const subject,
-			       int * const match, int ngroups,
+			       size_t len, int * const match, int ngroups,
 			       void * const group);
 	const char *vre2_capture(void *group, int refnum,
 				 const char ** const capture, int * const len);