cosmopolitan/libc/calls/fstat.c
Justine Tunney 965516e313
Make improvements for Actually Portable Emacs
- Get SIGWINCH working again on the New Technology
- Correctly handle O_NOFOLLOW in open() on Windows
- Implement synthetic umask() functionality on Windows
- Do a better job managing file execute access on Windows
- Fill in `st_uid` and `st_gid` with username hash on Windows
- Munge UNICODE control pictures into control codes on Windows
- Do a better job ensuring Windows console settings are restored
- Introduce KPRINTF_LOG environment variable to log kprintf to a file
2023-08-19 06:44:58 -07:00

63 lines
3.3 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/calls/internal.h"
#include "libc/calls/struct/stat.internal.h"
#include "libc/dce.h"
#include "libc/intrin/asan.internal.h"
#include "libc/intrin/describeflags.internal.h"
#include "libc/intrin/strace.internal.h"
#include "libc/intrin/weaken.h"
#include "libc/runtime/zipos.internal.h"
#include "libc/sysv/errfuns.h"
/**
* Returns information about file, via open()'d descriptor.
*
* On Windows, this implementation always sets `st_uid` and `st_gid` to
* `getuid()` and `getgid()`. The `st_mode` field is generated based on
* the current umask().
*
* @return 0 on success or -1 w/ errno
* @raise EBADF if `fd` isn't a valid file descriptor
* @raise EIO if an i/o error happens while reading from file system
* @raise EOVERFLOW shouldn't be possible on 64-bit systems
* @asyncsignalsafe
*/
int fstat(int fd, struct stat *st) {
int rc;
if (IsAsan() && !__asan_is_valid(st, sizeof(*st))) {
rc = efault();
} else if (__isfdkind(fd, kFdZip)) {
rc = _weaken(__zipos_fstat)(
(struct ZiposHandle *)(intptr_t)g_fds.p[fd].handle, st);
} else if (IsLinux() || IsXnu() || IsFreebsd() || IsOpenbsd() || IsNetbsd()) {
rc = sys_fstat(fd, st);
} else if (IsMetal()) {
rc = sys_fstat_metal(fd, st);
} else if (IsWindows()) {
rc = sys_fstat_nt(__getfdhandleactual(fd), st);
} else {
rc = enosys();
}
STRACE("fstat(%d, [%s]) → %d% m", fd, DescribeStat(rc, st), rc);
return rc;
}
__strong_reference(fstat, fstat64);