cosmopolitan/libc/calls/chmod.c

51 lines
2.8 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/dce.h"
#include "libc/sysv/consts/at.h"
#include "libc/sysv/errfuns.h"
/**
* Changes permissions on file, e.g.:
*
* CHECK_NE(-1, chmod("foo/bar.txt", 0644));
* CHECK_NE(-1, chmod("o/default/program.com", 0755));
* CHECK_NE(-1, chmod("privatefolder/", 0700));
*
* The esoteric bits generally available on System Five are:
*
* CHECK_NE(-1, chmod("/opt/", 01000)); // sticky bit
* CHECK_NE(-1, chmod("/usr/bin/sudo", 04755)); // setuid bit
* CHECK_NE(-1, chmod("/usr/bin/wall", 02755)); // setgid bit
*
* This works on Windows NT if you ignore the error ;-)
*
* @param pathname must exist
* @param mode contains octal flags (base 8)
* @errors ENOENT, ENOTDIR, ENOSYS
* @asyncsignalsafe
* @see fchmod()
* @syscall
*/
int chmod(const char *pathname, uint32_t mode) {
if (!pathname) return efault();
return fchmodat$sysv(AT_FDCWD, pathname, mode, 0);
}