cosmopolitan/libc/calls/select-nt.c
2024-10-07 15:29:53 -07:00

107 lines
4.1 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et 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/internal.h"
#include "libc/calls/state.internal.h"
#include "libc/calls/struct/timeval.h"
#include "libc/limits.h"
#include "libc/macros.h"
#include "libc/sock/select.h"
#include "libc/sock/sock.h"
#include "libc/sock/struct/pollfd.h"
#include "libc/sock/struct/pollfd.internal.h"
#include "libc/sysv/consts/poll.h"
#include "libc/sysv/errfuns.h"
#ifdef __x86_64__
// <sync libc/sysv/consts.sh>
#define POLLERR_ 0x0001 // implied in events
#define POLLHUP_ 0x0002 // implied in events
#define POLLNVAL_ 0x0004 // implied in events
#define POLLIN_ 0x0300
#define POLLRDNORM_ 0x0100
#define POLLRDBAND_ 0x0200
#define POLLOUT_ 0x0010
#define POLLWRNORM_ 0x0010
#define POLLWRBAND_ 0x0020 // MSDN undocumented
#define POLLPRI_ 0x0400 // MSDN unsupported
// </sync libc/sysv/consts.sh>
int sys_select_nt(int nfds, fd_set *readfds, fd_set *writefds,
fd_set *exceptfds, const struct timespec *timeout,
const sigset_t *sigmask) {
int pfds = 0;
// convert bitsets to pollfd
struct pollfd fds[128];
for (int fd = 0; fd < nfds; ++fd) {
int events = 0;
if (readfds && FD_ISSET(fd, readfds))
events |= POLLIN_;
if (writefds && FD_ISSET(fd, writefds))
events |= POLLOUT_;
if (exceptfds && FD_ISSET(fd, exceptfds))
events |= POLLPRI_;
if (events) {
if (pfds == ARRAYLEN(fds))
return e2big();
fds[pfds].fd = fd;
fds[pfds].events = events;
fds[pfds].revents = 0;
++pfds;
}
}
// call our nt poll implementation
int fdcount = sys_poll_nt(fds, pfds, timeout, sigmask);
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);
int bits = 0;
for (int i = 0; i < pfds; ++i) {
if (fds[i].revents & (POLLIN_ | POLLHUP_ | POLLERR_ | POLLNVAL_)) {
if (readfds) {
FD_SET(fds[i].fd, readfds);
++bits;
}
}
if (fds[i].revents & POLLOUT_) {
if (writefds) {
FD_SET(fds[i].fd, writefds);
++bits;
}
}
if (fds[i].revents & POLLPRI_) {
if (exceptfds) {
FD_SET(fds[i].fd, exceptfds);
++bits;
}
}
}
return bits;
}
#endif /* __x86_64__ */