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, 8 insertions, 0 deletions

diff --git a/strbuf.h b/strbuf.h
index 3dfeadb44c..a189f12b84 100644
--- a/strbuf.h
+++ b/strbuf.h
@@ -372,6 +372,14 @@ size_t strbuf_expand_dict_cb(struct strbuf *sb,
 			     void *context);
 
 /**
+ * If the string pointed to by `formatp` contains a percent sign ("%"),
+ * advance it to point to the character following the next one and
+ * return 1, otherwise return 0.  Append the substring before that
+ * percent sign to `sb`, or the whole string if there is none.
+ */
+int strbuf_expand_step(struct strbuf *sb, const char **formatp);
+
+/**
  * Append the contents of one strbuf to another, quoting any
  * percent signs ("%") into double-percents ("%%") in the
  * destination. This is useful for literal data to be fed to either