API: use an extern for mctp_log
Rather than having custom log implementations define their own macro for
libmctp_log, this change adds it as an extern symbol. This way,
implementations do not need to include function prototypes in config.h.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
diff --git a/libmctp-log.h b/libmctp-log.h
index e24738a..1024913 100644
--- a/libmctp-log.h
+++ b/libmctp-log.h
@@ -34,11 +34,8 @@
#elif defined(MCTP_LOG_CUSTOM)
-#include <config.h>
-
-#if !defined(mctp_prlog)
-#error Custom logging implementation enabled, but no definition for mctp_prlog
-#endif
+extern void mctp_prlog(int level, const char *fmt, ...)
+ __attribute__((format(printf, 2, 3)));
#else