Add compilation checks for printf-style format strings

Append the format() __attribute__ to function prototypes which
use a format string. This allows GCC to check for consistency
between the format string and its arguments when these
functions are called.

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>

1 files changed, 15 insertions, 15 deletions

diff --git a/accel-pppd/log.h b/accel-pppd/log.h
index 2ff2ac80..0b4c1cee 100644
--- a/accel-pppd/log.h
+++ b/accel-pppd/log.h
@@ -39,21 +39,21 @@ struct log_target_t
 
 void log_free_msg(struct log_msg_t *msg);
 
-void log_emerg(const char *fmt, ...);
-
-void log_error(const char *fmt,...);
-void log_warn(const char *fmt,...);
-void log_info1(const char *fmt,...);
-void log_info2(const char *fmt,...);
-void log_debug(const char *fmt,...);
-void log_msg(const char *fmt,...);
-
-void log_ppp_error(const char *fmt,...);
-void log_ppp_warn(const char *fmt,...);
-void log_ppp_info1(const char *fmt,...);
-void log_ppp_info2(const char *fmt,...);
-void log_ppp_debug(const char *fmt,...);
-void log_ppp_msg(const char *fmt,...);
+void log_emerg(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+
+void log_error(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_warn(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_info1(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_info2(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_debug(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_msg(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+
+void log_ppp_error(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_ppp_warn(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_ppp_info1(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_ppp_info2(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_ppp_debug(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
+void log_ppp_msg(const char *fmt, ...) __attribute__((format(gnu_printf, 1, 2)));
 
 void log_switch(struct triton_context_t *ctx, void *arg);