lchown: Use fchownat if arch does not have the lchown syscall

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>

Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>

libc/sysdeps/linux/common/lchown.c

@@ -11,17 +11,26 @@
 #include <unistd.h>
 #include <bits/wordsize.h>
 
-#if (__WORDSIZE == 32 && defined(__NR_lchown32)) || __WORDSIZE == 64
-# ifdef __NR_lchown32
-#  undef __NR_lchown
-#  define __NR_lchown __NR_lchown32
-# endif
+#if defined __NR_fchownat && !defined __NR_lchown
+# include <fcntl.h>
+int lchown(const char *path, uid_t owner, gid_t group)
+{
+	return fchownat(AT_FDCWD, path, owner, group, AT_SYMLINK_NOFOLLOW);
+}
+
+#else
+
+# if (__WORDSIZE == 32 && defined(__NR_lchown32)) || __WORDSIZE == 64
+#  ifdef __NR_lchown32
+#   undef __NR_lchown
+#   define __NR_lchown __NR_lchown32
+#  endif
 
 _syscall3(int, lchown, const char *, path, uid_t, owner, gid_t, group)
 
-#else
+# else
 
-# define __NR___syscall_lchown __NR_lchown
+#  define __NR___syscall_lchown __NR_lchown
 static __inline__ _syscall3(int, __syscall_lchown, const char *, path,
 		__kernel_uid_t, owner, __kernel_gid_t, group)
 
@@ -35,4 +44,6 @@ int lchown(const char *path, uid_t owner, gid_t group)
 	return __syscall_lchown(path, owner, group);
 }
 
+# endif
+
 #endif