strbuf: add xstrfmt helper

diff --git a/strbuf.h b/strbuf.h
index e9ad03eabe72dc2ee6e7e0086baca71d343264ce..a594c24b2b0e9e82c16de1bb787758d561cb2e7b 100644 (file)
--- a/strbuf.h
+++ b/strbuf.h
@@ -187,4 +187,13 @@ extern int fprintf_ln(FILE *fp, const char *fmt, ...);
 
 char *xstrdup_tolower(const char *);
 
+/*
+ * Create a newly allocated string using printf format. You can do this easily
+ * with a strbuf, but this provides a shortcut to save a few lines.
+ */
+__attribute__((format (printf, 1, 0)))
+char *xstrvfmt(const char *fmt, va_list ap);
+__attribute__((format (printf, 1, 2)))
+char *xstrfmt(const char *fmt, ...);
+
 #endif /* STRBUF_H */