cosmopolitan/libc/calls/getcwd-xnu.greg.c
Justine Tunney 3f0bcdc3ef
Improve cancellations, randomness, and time
- Exhaustively document cancellation points
- Rename SIGCANCEL to SIGTHR just like BSDs
- Further improve POSIX thread cancellations
- Ensure asynchronous cancellations work correctly
- Elevate the quality of getrandom() and getentropy()
- Make futexes cancel correctly on OpenBSD 6.x and 7.x
- Add reboot.com and shutdown.com to examples directory
- Remove underscore prefix from awesome timespec_*() APIs
- Create assertions that help verify our cancellation points
- Remove bad timespec APIs (cmp generalizes eq/ne/gt/gte/lt/lte)
2022-11-05 23:45:32 -07:00

69 lines
3.1 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 2021 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/struct/metastat.internal.h"
#include "libc/calls/struct/stat.h"
#include "libc/calls/syscall-sysv.internal.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/at.h"
#include "libc/sysv/consts/o.h"
#include "libc/sysv/errfuns.h"
#define XNU_F_GETPATH 50
#define XNU_MAXPATHLEN 1024
static inline bool CopyString(char *d, const char *s, size_t n) {
size_t i;
for (i = 0; i < n; ++i) {
if (!(d[i] = s[i])) {
return true;
}
}
return false;
}
char *sys_getcwd_xnu(char *res, size_t size) {
int fd;
union metastat st[2];
char buf[XNU_MAXPATHLEN], *ret = NULL;
if ((fd = __sys_openat_nc(AT_FDCWD, ".", O_RDONLY | O_DIRECTORY, 0)) != -1) {
if (__sys_fstat(fd, &st[0]) != -1) {
if (st[0].xnu.st_dev && st[0].xnu.st_ino) {
if (__sys_fcntl(fd, XNU_F_GETPATH, (uintptr_t)buf) != -1) {
if (__sys_fstatat(AT_FDCWD, buf, &st[1], 0) != -1) {
if (st[0].xnu.st_dev == st[1].xnu.st_dev &&
st[0].xnu.st_ino == st[1].xnu.st_ino) {
if (CopyString(res, buf, size)) {
ret = res;
} else {
erange();
}
} else {
einval();
}
}
}
} else {
einval();
}
}
close(fd);
}
return ret;
}