cosmopolitan/libc/calls/setfl.c
Justine Tunney c9fecf3a55
Make improvements
- You can now run `make -j8 toolchain` on Windows
- You can now run `make -j` on MacOS ARM64 and BSD OSes
- You can now use our Emacs dev environment on MacOS/Windows
- Fix bug where the x16 register was being corrupted by --ftrace
- The programs under build/bootstrap/ are updated as fat binaries
- The Makefile now explains how to download cosmocc-0.0.12 toolchain
- The build scripts under bin/ now support "cosmo" branded toolchains
- stat() now goes faster on Windows (shaves 100ms off `make` latency)
- Code cleanup and added review on the Windows signal checking code
- posix_spawnattr_setrlimit() now works around MacOS ARM64 bugs
- Landlock Make now favors posix_spawn() on non-Linux/OpenBSD
- posix_spawn() now has better --strace logging on Windows
- fstatat() can now avoid EACCES in more cases on Windows
- fchmod() can now change the readonly bit on Windows
2023-10-15 16:45:00 -07:00

73 lines
3.8 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 2023 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/createfileflags.internal.h"
#include "libc/calls/internal.h"
#include "libc/calls/struct/fd.internal.h"
#include "libc/calls/syscall_support-nt.internal.h"
#include "libc/nt/createfile.h"
#include "libc/nt/enum/fileflagandattributes.h"
#include "libc/nt/files.h"
#include "libc/nt/runtime.h"
#include "libc/sysv/consts/o.h"
textwindows int sys_fcntl_nt_setfl(int fd, unsigned flags) {
// you may change the following:
//
// - O_NONBLOCK make read() raise EAGAIN
// - O_APPEND for toggling append mode
// - O_RANDOM alt. for posix_fadvise()
// - O_SEQUENTIAL alt. for posix_fadvise()
// - O_DIRECT works but haven't tested
//
// the other bits are ignored.
unsigned allowed =
_O_APPEND | _O_SEQUENTIAL | _O_RANDOM | _O_DIRECT | _O_NONBLOCK;
unsigned needreo = _O_APPEND | _O_SEQUENTIAL | _O_RANDOM | _O_DIRECT;
unsigned newflag = (g_fds.p[fd].flags & ~allowed) | (flags & allowed);
if (g_fds.p[fd].kind == kFdFile &&
((g_fds.p[fd].flags & needreo) ^ (flags & needreo))) {
unsigned perm, share, attr;
if (GetNtOpenFlags(newflag, g_fds.p[fd].mode, &perm, &share, 0, &attr) ==
-1) {
return -1;
}
// MSDN says only these are allowed, otherwise it returns EINVAL.
attr &= kNtFileFlagBackupSemantics | kNtFileFlagDeleteOnClose |
kNtFileFlagNoBuffering | kNtFileFlagOpenNoRecall |
kNtFileFlagOpenReparsePoint | kNtFileFlagOverlapped |
kNtFileFlagPosixSemantics | kNtFileFlagRandomAccess |
kNtFileFlagSequentialScan | kNtFileFlagWriteThrough;
intptr_t hand;
if ((hand = ReOpenFile(g_fds.p[fd].handle, perm, share, attr)) != -1) {
if (hand != g_fds.p[fd].handle) {
CloseHandle(g_fds.p[fd].handle);
g_fds.p[fd].handle = hand;
}
} else {
return __winerr();
}
}
// 1. ignore flags that aren't access mode flags
// 2. return zero if nothing's changed
g_fds.p[fd].flags = newflag;
return 0;
}