1 //===--- Linux implementation of the Dir helpers --------------------------===//
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 "dir.h"
10
11 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
12
13 #include <errno.h>
14 #include <fcntl.h> // For open flags
15 #include <sys/syscall.h> // For syscall numbers
16
17 namespace __llvm_libc {
18
platform_opendir(const char * name)19 int platform_opendir(const char *name) {
20 int open_flags = O_RDONLY | O_DIRECTORY | O_CLOEXEC;
21 #ifdef SYS_open
22 int fd = __llvm_libc::syscall(SYS_open, name, open_flags);
23 #elif defined(SYS_openat)
24 int fd = __llvm_libc::syscall(SYS_openat, AT_FDCWD, name, open_flags);
25 #else
26 #error \
27 "SYS_open and SYS_openat syscalls not available to perform an open operation."
28 #endif
29
30 if (fd < 0) {
31 errno = -fd;
32 return -1;
33 }
34 return fd;
35 }
36
platform_fetch_dirents(int fd,cpp::MutableArrayRef<uint8_t> buffer)37 size_t platform_fetch_dirents(int fd, cpp::MutableArrayRef<uint8_t> buffer) {
38 long size =
39 __llvm_libc::syscall(SYS_getdents, fd, buffer.data(), buffer.size());
40 if (size < 0) {
41 errno = -size;
42 return 0;
43 }
44 return size;
45 }
46
platform_closedir(int fd)47 bool platform_closedir(int fd) {
48 long ret = __llvm_libc::syscall(SYS_close, fd);
49 if (ret < 0) {
50 errno = -ret;
51 return false;
52 }
53 return true;
54 }
55
56 } // namespace __llvm_libc
57