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/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2021, sin-ack <sin-ack@protonmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <bits/pthread_cancel.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdarg.h>
#include <string.h>
#include <syscall.h>
#include <time.h>
extern "C" {
int fcntl(int fd, int cmd, ...)
{
__pthread_maybe_cancel();
va_list ap;
va_start(ap, cmd);
uintptr_t extra_arg = va_arg(ap, uintptr_t);
int rc = syscall(SC_fcntl, fd, cmd, extra_arg);
va_end(ap);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
int create_inode_watcher(unsigned flags)
{
int rc = syscall(SC_create_inode_watcher, flags);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
int inode_watcher_add_watch(int fd, char const* path, size_t path_length, unsigned event_mask)
{
Syscall::SC_inode_watcher_add_watch_params params { { path, path_length }, fd, event_mask };
int rc = syscall(SC_inode_watcher_add_watch, ¶ms);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
int inode_watcher_remove_watch(int fd, int wd)
{
int rc = syscall(SC_inode_watcher_remove_watch, fd, wd);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
int creat(char const* path, mode_t mode)
{
__pthread_maybe_cancel();
return open(path, O_CREAT | O_WRONLY | O_TRUNC, mode);
}
int open(char const* path, int options, ...)
{
__pthread_maybe_cancel();
if (!path) {
errno = EFAULT;
return -1;
}
auto path_length = strlen(path);
if (path_length > INT32_MAX) {
errno = EINVAL;
return -1;
}
va_list ap;
va_start(ap, options);
auto mode = (mode_t)va_arg(ap, unsigned);
va_end(ap);
Syscall::SC_open_params params { AT_FDCWD, { path, path_length }, options, mode };
int rc = syscall(SC_open, ¶ms);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
int openat(int dirfd, char const* path, int options, ...)
{
__pthread_maybe_cancel();
if (!path) {
errno = EFAULT;
return -1;
}
auto path_length = strlen(path);
if (path_length > INT32_MAX) {
errno = EINVAL;
return -1;
}
va_list ap;
va_start(ap, options);
auto mode = (mode_t)va_arg(ap, unsigned);
va_end(ap);
Syscall::SC_open_params params { dirfd, { path, path_length }, options, mode };
int rc = syscall(SC_open, ¶ms);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
// https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_fadvise.html
int posix_fadvise(int fd, off_t offset, off_t len, int advice)
{
// Per POSIX:
// "The posix_fadvise() function shall have no effect on the semantics of other operations on the specified data,
// although it may affect the performance of other operations."
// For now, we simply ignore posix_fadvise() requests. In the future we may use them to optimize performance.
(void)fd;
(void)offset;
(void)len;
(void)advice;
return 0;
}
// https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_fallocate.html
int posix_fallocate(int fd, off_t offset, off_t len)
{
// posix_fallocate does not set errno.
return static_cast<int>(syscall(SC_posix_fallocate, fd, &offset, &len));
}
// https://pubs.opengroup.org/onlinepubs/9699919799/functions/utimensat.html
int utimensat(int dirfd, char const* path, struct timespec const times[2], int flag)
{
if (!path) {
errno = EFAULT;
return -1;
}
size_t path_length = strlen(path);
if (path_length > INT32_MAX) {
errno = EINVAL;
return -1;
}
// POSIX allows AT_SYMLINK_NOFOLLOW flag or no flags.
if (flag & ~AT_SYMLINK_NOFOLLOW) {
errno = EINVAL;
return -1;
}
// Return early without error since both changes are to be omitted.
if (times && times[0].tv_nsec == UTIME_OMIT && times[1].tv_nsec == UTIME_OMIT)
return 0;
// According to POSIX, when times is a nullptr, it's equivalent to setting
// both last access time and last modification time to the current time.
// Setting the times argument to nullptr if it matches this case prevents
// the need to copy it in the kernel.
if (times && times[0].tv_nsec == UTIME_NOW && times[1].tv_nsec == UTIME_NOW)
times = nullptr;
if (times) {
for (int i = 0; i < 2; ++i) {
if ((times[i].tv_nsec != UTIME_NOW && times[i].tv_nsec != UTIME_OMIT)
&& (times[i].tv_nsec < 0 || times[i].tv_nsec >= 1'000'000'000L)) {
errno = EINVAL;
return -1;
}
}
}
Syscall::SC_utimensat_params params { dirfd, { path, path_length }, times, flag };
int rc = syscall(SC_utimensat, ¶ms);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
}
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