cosmopolitan/libc/sock/select-nt.c
Justine Tunney 933411ba99 Improve synchronization
- Fix bugs in kDos2Errno definition
- malloc() should now be thread safe
- Fix bug in rollup.com header generator
- Fix open(O_APPEND) on the New Technology
- Fix select() on the New Technology and test it
- Work towards refactoring i/o for thread safety
- Socket reads and writes on NT now poll for signals
- Work towards i/o completion ports on the New Technology
- Make read() and write() intermittently check for signals
- Blinkenlights keyboard i/o so much better on NT w/ poll()
- You can now poll() files and sockets at the same time on NT
- Fix bug in appendr() that manifests with dlmalloc footers off
2022-04-15 15:31:55 -07:00

81 lines
3.6 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/struct/timeval.h"
#include "libc/macros.internal.h"
#include "libc/sock/internal.h"
#include "libc/sock/select.h"
#include "libc/sock/sock.h"
#include "libc/sysv/consts/poll.h"
#include "libc/sysv/errfuns.h"
int sys_select_nt(int nfds, fd_set *readfds, fd_set *writefds,
fd_set *exceptfds, struct timeval *timeout) {
uint64_t millis;
int i, pfds, events, fdcount;
struct pollfd fds[64];
// check for interrupts early before doing work
if (_check_interrupts(false, g_fds.p)) return eintr();
// convert bitsets to pollfd
for (pfds = i = 0; i < nfds; ++i) {
events = 0;
if (readfds && FD_ISSET(i, readfds)) events |= POLLIN;
if (writefds && FD_ISSET(i, writefds)) events |= POLLOUT;
if (exceptfds && FD_ISSET(i, exceptfds)) events |= POLLERR;
if (events) {
if (pfds < ARRAYLEN(fds)) {
fds[pfds].fd = i;
fds[pfds].events = events;
fds[pfds].revents = 0;
pfds += 1;
} else {
return enomem();
}
}
}
// convert the wait time to a word
if (!timeout || __builtin_add_overflow(timeout->tv_sec,
timeout->tv_usec / 1000, &millis)) {
millis = -1;
}
// call our nt poll implementation
fdcount = sys_poll_nt(fds, pfds, &millis);
if (fdcount == -1) return -1;
// convert pollfd back to bitsets
if (readfds) FD_ZERO(readfds);
if (writefds) FD_ZERO(writefds);
if (exceptfds) FD_ZERO(exceptfds);
for (i = 0; i < fdcount; ++i) {
if (fds[i].revents & POLLIN) FD_SET(fds[i].fd, readfds);
if (fds[i].revents & POLLOUT) FD_SET(fds[i].fd, writefds);
if (fds[i].revents & (POLLERR | POLLNVAL)) FD_SET(fds[i].fd, exceptfds);
}
// store remaining time back in caller's timeval
if (timeout) {
timeout->tv_sec = millis / 1000;
timeout->tv_usec = millis % 1000 * 1000;
}
return fdcount;
}