[PATCH 7/9] strbuf: implement strbuf_strip_suffix

[Jeff King <peff@peff.net>]

You can almost get away with just calling "strip_suffix_mem"
on a strbuf's buf and len fields. But we also need to move
the NUL-terminator to satisfy strbuf's invariants. Let's
provide a convenience wrapper that handles this.

Signed-off-by: Jeff King <peff@peff.net>
---
I called strbuf_setlen here because it seemed sensible to use that as an
opaque building block, but we are violating the invariant here for a
moment by setting sb->len for a moment. I think that is fine, as this is
a strbuf function, and can violate the invariant for a moment if it
wants to.

But if we care, we can keep a separate "size_t len" variable, and
strbuf_setlen to that.

Or we can make it less opaque, and replace the setlen with
"sb->buf[sb->len] = 0".

 strbuf.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/strbuf.h b/strbuf.h
index e9ad03e..ec11742 100644
--- a/strbuf.h
+++ b/strbuf.h
@@ -49,6 +49,15 @@ extern int strbuf_reencode(struct strbuf *sb, const char *from, const char *to);
 extern void strbuf_tolower(struct strbuf *sb);
 extern int strbuf_cmp(const struct strbuf *, const struct strbuf *);
 
+static inline int strbuf_strip_suffix(struct strbuf *sb, const char *suffix)
+{
+	if (strip_suffix_mem(sb->buf, &sb->len, suffix)) {
+		strbuf_setlen(sb, sb->len);
+		return 1;
+	} else
+		return 0;
+}
+
 /*
  * Split str (of length slen) at the specified terminator character.
  * Return a null-terminated array of pointers to strbuf objects
-- 
2.0.0.566.gfe3e6b2