strbuf: factor out strbuf_expand_step()

Extract the part of strbuf_expand that finds the next placeholder into a
new function.  It allows to build parsers without callback functions and
the overhead imposed by them.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 14 insertions, 14 deletions

diff --git a/strbuf.c b/strbuf.c
index 08eec8f1d8..a90b597da1 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -415,19 +415,24 @@ void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 	strbuf_setlen(sb, sb->len + len);
 }
 
+int strbuf_expand_step(struct strbuf *sb, const char **formatp)
+{
+	const char *format = *formatp;
+	const char *percent = strchrnul(format, '%');
+
+	strbuf_add(sb, format, percent - format);
+	if (!*percent)
+		return 0;
+	*formatp = percent + 1;
+	return 1;
+}
+
 void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
 		   void *context)
 {
-	for (;;) {
-		const char *percent;
+	while (strbuf_expand_step(sb, &format)) {
 		size_t consumed;
 
-		percent = strchrnul(format, '%');
-		strbuf_add(sb, format, percent - format);
-		if (!*percent)
-			break;
-		format = percent + 1;
-
 		if (*format == '%') {
 			strbuf_addch(sb, '%');
 			format++;
@@ -1022,12 +1027,7 @@ void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 	 * we want for %z, but the computation for %s has to convert to number
 	 * of seconds.
 	 */
-	for (;;) {
-		const char *percent = strchrnul(fmt, '%');
-		strbuf_add(&munged_fmt, fmt, percent - fmt);
-		if (!*percent)
-			break;
-		fmt = percent + 1;
+	while (strbuf_expand_step(&munged_fmt, &fmt)) {
 		switch (*fmt) {
 		case '%':
 			strbuf_addstr(&munged_fmt, "%%");