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