kern/{,s}printf: guard against direct inclusion

2 files changed, 7 insertions, 0 deletions

diff --git a/kern/printf.h b/kern/printf.h
index efaf2f9c..16a7b584 100644
--- a/kern/printf.h
+++ b/kern/printf.h
@@ -27,6 +27,10 @@
 #ifndef _KERN_PRINTK_H
 #define _KERN_PRINTK_H
 
+#ifndef _STDIO_H
+#error "do not use <kern/printf.h> directly; include <stdio.h> instead"
+#endif /* _STDIO_H */
+
 #include <stdarg.h>
 
 #include <kern/macros.h>
diff --git a/kern/sprintf.h b/kern/sprintf.h
index 0c097953..0c3fb839 100644
--- a/kern/sprintf.h
+++ b/kern/sprintf.h
@@ -28,6 +28,9 @@
 #ifndef _KERN_SPRINTF_H
 #define _KERN_SPRINTF_H
 
+#ifndef _STDIO_H
+#error "do not use <kern/sprintf.h> directly; include <stdio.h> instead"
+#endif /* _STDIO_H */
 #include <stdarg.h>
 
 #include <kern/macros.h>