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 "src/__support/File/dir.h"
10
11 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
12 #include "src/__support/error_or.h"
13 #include "src/__support/macros/config.h"
14
15 #include "hdr/fcntl_macros.h" // For open flags
16 #include <sys/syscall.h> // For syscall numbers
17
18 namespace LIBC_NAMESPACE_DECL {
19
platform_opendir(const char * name)20 ErrorOr<int> platform_opendir(const char *name) {
21 int open_flags = O_RDONLY | O_DIRECTORY | O_CLOEXEC;
22 #ifdef SYS_open
23 int fd = LIBC_NAMESPACE::syscall_impl<int>(SYS_open, name, open_flags);
24 #elif defined(SYS_openat)
25 int fd =
26 LIBC_NAMESPACE::syscall_impl<int>(SYS_openat, AT_FDCWD, name, open_flags);
27 #else
28 #error \
29 "SYS_open and SYS_openat syscalls not available to perform an open operation."
30 #endif
31
32 if (fd < 0) {
33 return LIBC_NAMESPACE::Error(-fd);
34 }
35 return fd;
36 }
37
platform_fetch_dirents(int fd,cpp::span<uint8_t> buffer)38 ErrorOr<size_t> platform_fetch_dirents(int fd, cpp::span<uint8_t> buffer) {
39 #ifdef SYS_getdents64
40 long size = LIBC_NAMESPACE::syscall_impl<long>(SYS_getdents64, fd,
41 buffer.data(), buffer.size());
42 #else
43 #error "getdents64 syscalls not available to perform a fetch dirents operation."
44 #endif
45
46 if (size < 0) {
47 return LIBC_NAMESPACE::Error(static_cast<int>(-size));
48 }
49 return size;
50 }
51
platform_closedir(int fd)52 int platform_closedir(int fd) {
53 int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_close, fd);
54 if (ret < 0) {
55 return static_cast<int>(-ret);
56 }
57 return 0;
58 }
59
60 } // namespace LIBC_NAMESPACE_DECL
61