[klibc] Use <stdarg.h> features in open() and openat()

Looking in klibc-1.5.21 I see that the published prototype for open() is:

__extern int open(const char *, int, ...);

This looks fine, but the actual definition (which deliberately doesn't see the
above prototype) is:

int open(const char *pathname, int flags, mode_t mode)
{ ... }

This is invalid C, and very sloppy programming.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47533

Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Thorsten Glaser <tg@mirbsd.de>
Signed-off-by: maximilian attems <max@stro.at>

4 files changed, 24 insertions, 8 deletions

diff --git a/usr/include/fcntl.h b/usr/include/fcntl.h
index 0908e2174d0d5..c94b2be371d98 100644
--- a/usr/include/fcntl.h
+++ b/usr/include/fcntl.h
@@ -35,10 +35,8 @@
 #endif
 
 /* This is defined here as well as in <unistd.h> */
-#ifndef _KLIBC_IN_OPEN_C
 __extern int open(const char *, int, ...);
 __extern int openat(int, const char *, int, ...);
-#endif
 
 __extern int creat(const char *, mode_t);
 __extern int fcntl(int, int, ...);
diff --git a/usr/include/unistd.h b/usr/include/unistd.h
index 97760d4eb4995..0d3205e1cd08f 100644
--- a/usr/include/unistd.h
+++ b/usr/include/unistd.h
@@ -82,10 +82,8 @@ __extern int lchown(const char *, uid_t, gid_t);
 __extern char *getcwd(char *, size_t);
 
 /* Also in <fcntl.h> */
-#ifndef _KLIBC_IN_OPEN_C
 __extern int open(const char *, int, ...);
 __extern int openat(int, const char *, int, ...);
-#endif
 __extern int creat(const char *, mode_t);
 __extern int open_cloexec(const char *, int, mode_t);
 __extern int close(int);
diff --git a/usr/klibc/open.c b/usr/klibc/open.c
index 9b0897a77927a..290f9590892d6 100644
--- a/usr/klibc/open.c
+++ b/usr/klibc/open.c
@@ -5,17 +5,27 @@
  * system call, to indicate that we're 64-bit safe.
  */
 
-#define _KLIBC_IN_OPEN_C
 #include <unistd.h>
 #include <fcntl.h>
 #include <bitsize.h>
+#include <stdarg.h>
 
 #if _BITSIZE == 32 && !defined(__i386__)
 
 extern int __open(const char *, int, mode_t);
 
-int open(const char *pathname, int flags, mode_t mode)
+int open(const char *pathname, int flags, ...)
 {
+	mode_t mode = 0;
+
+	if (flags & O_CREAT) {
+		va_list ap;
+
+		va_start(ap, flags);
+		mode = va_arg(ap, mode_t);
+		va_end(ap);
+	}
+
 	return __open(pathname, flags | O_LARGEFILE, mode);
 }
 
diff --git a/usr/klibc/openat.c b/usr/klibc/openat.c
index 83c87cd49b1f4..0609b832c1858 100644
--- a/usr/klibc/openat.c
+++ b/usr/klibc/openat.c
@@ -5,17 +5,27 @@
  * system call, to indicate that we're 64-bit safe.
  */
 
-#define _KLIBC_IN_OPEN_C
 #include <unistd.h>
 #include <fcntl.h>
 #include <bitsize.h>
+#include <stdarg.h>
 
 #if _BITSIZE == 32 && !defined(__i386__) && defined(__NR_openat)
 
 extern int __openat(int, const char *, int, mode_t);
 
-int openat(int dirfd, const char *pathname, int flags, mode_t mode)
+int openat(int dirfd, const char *pathname, int flags, ...)
 {
+	mode_t mode = 0;
+
+	if (flags & O_CREAT) {
+		va_list ap;
+
+		va_start(ap, flags);
+		mode = va_arg(ap, mode_t);
+		va_end(ap);
+	}
+
 	return __openat(dirfd, pathname, flags | O_LARGEFILE, mode);
 }