1 //===-- Implementation of openat ------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "src/fcntl/openat.h" 10 11 #include "src/__support/OSUtil/syscall.h" // For internal syscall function. 12 #include "src/__support/common.h" 13 #include "src/__support/macros/config.h" 14 #include "src/errno/libc_errno.h" 15 16 #include "hdr/types/mode_t.h" 17 #include <stdarg.h> 18 #include <sys/syscall.h> // For syscall numbers. 19 20 namespace LIBC_NAMESPACE_DECL { 21 22 LLVM_LIBC_FUNCTION(int, openat, (int dfd, const char *path, int flags, ...)) { 23 mode_t mode_flags = 0; 24 // O_TMPFILE is a multi-bit flag so we test all bits by checking for equality 25 // with O_TMPFILE 26 if ((flags & O_CREAT) || (flags & O_TMPFILE) == O_TMPFILE) { 27 va_list varargs; 28 va_start(varargs, flags); 29 mode_flags = va_arg(varargs, mode_t); 30 va_end(varargs); 31 } 32 33 int fd = LIBC_NAMESPACE::syscall_impl<int>(SYS_openat, dfd, path, flags, 34 mode_flags); 35 if (fd > 0) 36 return fd; 37 38 libc_errno = -fd; 39 return -1; 40 } 41 42 } // namespace LIBC_NAMESPACE_DECL 43