cosmopolitan/libc/sock/wsablock.c
Justine Tunney 33d280c8ba
Improve Windows Console I/O
- Blocking read operations on the Windows Console can now EINTR
- Blocking read operations on Windows pipes now EINTR more reliably
- setitimer() will no longer be inherited across fork() on Windows
- It's now possible to use ECHO when the console is in raw mode
- The ECHOCTL flag now works correctly on the Windows Console
- The ICRNL flag now works correctly on the Windows Console
- pread() and pwrite() will now raise ESPIPE on Windows
- Opening /dev/tty on Windows is improved (untested)
- Overlapped I/O is now implemented in a better way
2023-08-08 05:44:40 -07:00

97 lines
4.4 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 2022 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/assert.h"
#include "libc/calls/internal.h"
#include "libc/calls/sig.internal.h"
#include "libc/errno.h"
#include "libc/intrin/kprintf.h"
#include "libc/nt/enum/wait.h"
#include "libc/nt/enum/wsa.h"
#include "libc/nt/errors.h"
#include "libc/nt/runtime.h"
#include "libc/nt/synchronization.h"
#include "libc/nt/thread.h"
#include "libc/nt/winsock.h"
#include "libc/runtime/runtime.h"
#include "libc/sock/internal.h"
#include "libc/sock/sock.h"
#include "libc/sock/syscall_fd.internal.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/o.h"
#include "libc/sysv/errfuns.h"
static textwindows void __wsablock_abort(int64_t handle,
struct NtOverlapped *overlapped) {
unassert(CancelIoEx(handle, overlapped) ||
GetLastError() == kNtErrorNotFound);
}
textwindows int __wsablock(struct Fd *fd, struct NtOverlapped *overlapped,
uint32_t *flags, int sigops, uint32_t timeout) {
uint32_t i, got;
int rc, abort_errno;
if (WSAGetLastError() != kNtErrorIoPending) {
// our i/o operation never happened because it failed
return __winsockerr();
}
// our i/o operation is in flight and it needs to block
abort_errno = EAGAIN;
if (fd->flags & O_NONBLOCK) {
__wsablock_abort(fd->handle, overlapped);
} else if (_check_interrupts(sigops, g_fds.p)) {
Interrupted:
abort_errno = errno; // EINTR or ECANCELED
__wsablock_abort(fd->handle, overlapped);
} else {
for (;;) {
i = WSAWaitForMultipleEvents(1, &overlapped->hEvent, true,
__SIG_POLLING_INTERVAL_MS, true);
if (i == kNtWaitFailed || i == kNtWaitTimeout) {
if (_check_interrupts(sigops, g_fds.p)) {
goto Interrupted;
}
if (i == kNtWaitFailed) {
// Failure should be an impossible condition, but MSDN lists
// WSAENETDOWN and WSA_NOT_ENOUGH_MEMORY as possible errors,
// which we're going to hope are ephemeral.
SleepEx(__SIG_POLLING_INTERVAL_MS, false);
}
if (timeout) {
if (timeout <= __SIG_POLLING_INTERVAL_MS) {
__wsablock_abort(fd->handle, overlapped);
break;
}
timeout -= __SIG_POLLING_INTERVAL_MS;
}
} else {
break;
}
}
}
// overlapped is allocated on stack by caller, so it's important that
// we wait for win32 to acknowledge that it's done using that memory.
if (WSAGetOverlappedResult(fd->handle, overlapped, &got, true, flags)) {
return got;
} else if (WSAGetLastError() == kNtErrorOperationAborted) {
errno = abort_errno;
return -1;
} else {
return -1;
}
}