use __attribute__ to catch printf format mistakes

Use "__attribute__((format (printf,N,M)))", as is done in git, do catch
mistakes in printf-style format strings.

Signed-off-by: Mark Lodato <lodatom@gmail.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/html.h b/html.h
index 16d55ec..1135fb8 100644
--- a/html.h
+++ b/html.h
@@ -1,16 +1,19 @@
 #ifndef HTML_H
 #define HTML_H
 
 extern int htmlfd;
 
 extern void html_raw(const char *txt, size_t size);
 extern void html(const char *txt);
+
+__attribute__((format (printf,1,2)))
 extern void htmlf(const char *format,...);
+
 extern void html_status(int code, const char *msg, int more_headers);
 extern void html_txt(const char *txt);
 extern void html_ntxt(int len, const char *txt);
 extern void html_attr(const char *txt);
 extern void html_url_path(const char *txt);
 extern void html_url_arg(const char *txt);
 extern void html_hidden(const char *name, const char *value);
 extern void html_option(const char *value, const char *text, const char *selected_value);