strbuf: give URL-encoding API a char predicate fn

Allow callers to specify exactly what characters need to be URL-encoded
and which do not. This new API will be taken advantage of in a patch
later in this set.

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Matthew DeVore <matvore@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

credential-store.c

@@ -72,15 +72,16 @@ static void store_credential_file(const char *fn, struct credential *c)
 	struct strbuf buf = STRBUF_INIT;
 
 	strbuf_addf(&buf, "%s://", c->protocol);
-	strbuf_addstr_urlencode(&buf, c->username, 1);
+	strbuf_addstr_urlencode(&buf, c->username, is_rfc3986_unreserved);
 	strbuf_addch(&buf, ':');
-	strbuf_addstr_urlencode(&buf, c->password, 1);
+	strbuf_addstr_urlencode(&buf, c->password, is_rfc3986_unreserved);
 	strbuf_addch(&buf, '@');
 	if (c->host)
-		strbuf_addstr_urlencode(&buf, c->host, 1);
+		strbuf_addstr_urlencode(&buf, c->host, is_rfc3986_unreserved);
 	if (c->path) {
 		strbuf_addch(&buf, '/');
-		strbuf_addstr_urlencode(&buf, c->path, 0);
+		strbuf_addstr_urlencode(&buf, c->path,
+					is_rfc3986_reserved_or_unreserved);
 	}
 
 	rewrite_credential_file(fn, c, &buf);

http.c

@@ -513,9 +513,11 @@ static void set_proxyauth_name_password(CURL *result)
 #else
 		struct strbuf s = STRBUF_INIT;
 
-		strbuf_addstr_urlencode(&s, proxy_auth.username, 1);
+		strbuf_addstr_urlencode(&s, proxy_auth.username,
+					is_rfc3986_unreserved);
 		strbuf_addch(&s, ':');
-		strbuf_addstr_urlencode(&s, proxy_auth.password, 1);
+		strbuf_addstr_urlencode(&s, proxy_auth.password,
+					is_rfc3986_unreserved);
 		curl_proxyuserpwd = strbuf_detach(&s, NULL);
 		curl_easy_setopt(result, CURLOPT_PROXYUSERPWD, curl_proxyuserpwd);
 #endif

strbuf.c

@@ -774,8 +774,10 @@ void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
 	}
 }
 
-static int is_rfc3986_reserved(char ch)
+int is_rfc3986_reserved_or_unreserved(char ch)
 {
+	if (is_rfc3986_unreserved(ch))
+		return 1;
 	switch (ch) {
 		case '!': case '*': case '\'': case '(': case ')': case ';':
 		case ':': case '@': case '&': case '=': case '+': case '$':
@@ -785,20 +787,19 @@ static int is_rfc3986_reserved(char ch)
 	return 0;
 }
 
-static int is_rfc3986_unreserved(char ch)
+int is_rfc3986_unreserved(char ch)
 {
 	return isalnum(ch) ||
 		ch == '-' || ch == '_' || ch == '.' || ch == '~';
 }
 
 static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
-				 int reserved)
+				 char_predicate allow_unencoded_fn)
 {
 	strbuf_grow(sb, len);
 	while (len--) {
 		char ch = *s++;
-		if (is_rfc3986_unreserved(ch) ||
+		if (allow_unencoded_fn(ch))
-		    (!reserved && is_rfc3986_reserved(ch)))
 			strbuf_addch(sb, ch);
 		else
 			strbuf_addf(sb, "%%%02x", (unsigned char)ch);
@@ -806,9 +807,9 @@ static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
 }
 
 void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
-			     int reserved)
+			     char_predicate allow_unencoded_fn)
 {
-	strbuf_add_urlencode(sb, s, strlen(s), reserved);
+	strbuf_add_urlencode(sb, s, strlen(s), allow_unencoded_fn);
 }
 
 void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)

strbuf.h

@@ -666,8 +666,13 @@ void strbuf_branchname(struct strbuf *sb, const char *name,
  */
 int strbuf_check_branch_ref(struct strbuf *sb, const char *name);
 
+typedef int (*char_predicate)(char ch);
+
+int is_rfc3986_unreserved(char ch);
+int is_rfc3986_reserved_or_unreserved(char ch);
+
 void strbuf_addstr_urlencode(struct strbuf *sb, const char *name,
-			     int reserved);
+			     char_predicate allow_unencoded_fn);
 
 __attribute__((format (printf,1,2)))
 int printf_ln(const char *fmt, ...);