add some consts

src/vre2/vre2.cpp

@@ -56,14 +56,14 @@ vre2::~vre2() {
 }
 
 inline bool
-vre2::match(const char *subject, int ngroups, StringPiece* groups)
+vre2::match(const char *subject, const int ngroups, StringPiece* groups) const
 {
 	return re_->Match(subject, 0, strlen(subject), RE2::UNANCHORED,
 	    groups, ngroups + 1);
 }
 
-inline int
-vre2::ngroups()
+inline const int
+vre2::ngroups() const
 {
 	return re_->NumberOfCapturingGroups();
 }
@@ -85,8 +85,8 @@ vre2_matchsz(void)
 }
 
 const char *
-vre2_match(vre2 *vre2, const char *subject, int *match, int ngroups,
-    void *group)
+vre2_match(vre2 *vre2, const char * const subject, int * const match,
+    const int ngroups, void * const group)
 {
 	try {
 		StringPiece* g = reinterpret_cast<StringPiece *>(group);
@@ -97,7 +97,8 @@ vre2_match(vre2 *vre2, const char *subject, int *match, int ngroups,
 }
 
 const char *
-vre2_capture(void *group, int refnum, const char **capture, int *len)
+vre2_capture(void *group, const int refnum, const char ** const capture,
+    int * const len)
 {
 	try {
 		StringPiece* g = reinterpret_cast<StringPiece *>(group);
@@ -110,7 +111,7 @@ vre2_capture(void *group, int refnum, const char **capture, int *len)
 }
 
 const char *
-vre2_ngroups(vre2 *vre2, int *ngroups)
+vre2_ngroups(vre2 *vre2, int * const ngroups)
 {
 	try {
 		*ngroups = vre2->ngroups();

src/vre2/vre2.h

@@ -43,8 +43,8 @@ private:
 public:
 	vre2(const char *pattern);
 	virtual ~vre2();
-	bool match(const char *subject, int ngroups, StringPiece* groups);
-	int ngroups();
+	bool match(const char *subject, int ngroups, StringPiece* groups) const;
+	const int ngroups() const;
 };
 #else
 typedef struct vre2 vre2;
@@ -54,14 +54,15 @@ typedef struct vre2 vre2;
 extern "C" {
 #endif
 
-	const char *vre2_init(vre2 **vre2, const char *pattern);
+	const char *vre2_init(vre2 **vre2, const char * pattern);
 	const char *vre2_fini(vre2 **vre2);
 	const size_t vre2_matchsz(void);
-	const char *vre2_ngroups(vre2 *vre2, int *ngroups);
-	const char *vre2_match(vre2 *vre2, const char *subject, int *match,
-			       int ngroups, void *group);
-	const char *vre2_capture(void *group, int refnum, const char **capture,
-				 int *len);
+	const char *vre2_ngroups(vre2 *vre2, int * const ngroups);
+	const char *vre2_match(vre2 *vre2, const char * const subject,
+			       int * const match, int ngroups,
+			       void * const group);
+	const char *vre2_capture(void *group, int refnum,
+				 const char ** const capture, int * const len);
 
 #ifdef __cplusplus
 }