commit b115aefbb3a472c605e167e09d14b1a797337e77
author Elliott Hughes <enh@google.com> Fri Aug 04 09:34:19 2017 -0700
committer Elliott Hughes <enh@google.com> Fri Aug 04 10:20:18 2017 -0700
tree 4167aea0a211331deb64f66e3dfd6d931d20f246
parent cc3639b3eeb30cc4e994714254e8f995e77b30bf

With O_TMPFILE, open(2) takes a mode argument.

Strictly, the mode isn't really meaningful unless you supply O_EXCL,
but the kernel will take it and fstat will return it even if you
never give the file a name.

Also warn for O_TMPFILE without a mode at compile time where possible.

Bug: N/A
Test: ran tests
Change-Id: I729b6d6e6190676fd017a1190b6200bf9abdbfd8

libc/include/bits/fortify/fcntl.h

diff --git a/libc/include/bits/fortify/fcntl.h b/libc/include/bits/fortify/fcntl.h
index 6b6b29c..6d90341 100644
--- a/libc/include/bits/fortify/fcntl.h
+++ b/libc/include/bits/fortify/fcntl.h
@@ -40,7 +40,7 @@
 
 #if defined(__BIONIC_FORTIFY)
 #define __open_too_many_args_error "too many arguments"
-#define __open_too_few_args_error "called with O_CREAT, but missing mode"
+#define __open_too_few_args_error "called with O_CREAT or O_TMPFILE, but missing mode"
 #define __open_useless_modes_warning "has superfluous mode bits; missing O_CREAT?"
 /* O_TMPFILE shares bits with O_DIRECTORY. */
 #define __open_modes_useful(flags) (((flags) & O_CREAT) || ((flags) & O_TMPFILE) == O_TMPFILE)
@@ -60,7 +60,7 @@
 __BIONIC_FORTIFY_INLINE
 int open(const char* const __pass_object_size pathname, int flags)
         __overloadable
-        __clang_error_if(flags & O_CREAT, "'open' " __open_too_few_args_error) {
+        __clang_error_if(__open_modes_useful(flags), "'open' " __open_too_few_args_error) {
     return __open_2(pathname, flags);
 }
 
@@ -80,7 +80,7 @@
 __BIONIC_FORTIFY_INLINE
 int openat(int dirfd, const char* const __pass_object_size pathname, int flags)
         __overloadable
-        __clang_error_if(flags & O_CREAT, "'openat' " __open_too_few_args_error) {
+        __clang_error_if(__open_modes_useful(flags), "'openat' " __open_too_few_args_error) {
     return __openat_2(dirfd, pathname, flags);
 }
 
@@ -101,7 +101,7 @@
 __BIONIC_FORTIFY_INLINE
 int open(const char* pathname, int flags, ...) {
     if (__builtin_constant_p(flags)) {
-        if ((flags & O_CREAT) && __builtin_va_arg_pack_len() == 0) {
+        if (__open_modes_useful(flags) && __builtin_va_arg_pack_len() == 0) {
             __creat_missing_mode();  /* Compile time error. */
         }
     }
@@ -120,7 +120,7 @@
 __BIONIC_FORTIFY_INLINE
 int openat(int dirfd, const char* pathname, int flags, ...) {
     if (__builtin_constant_p(flags)) {
-        if ((flags & O_CREAT) && __builtin_va_arg_pack_len() == 0) {
+        if (__open_modes_useful(flags) && __builtin_va_arg_pack_len() == 0) {
             __creat_missing_mode();  /* Compile time error. */
         }
     }