138 lines
3.4 KiB
C++
138 lines
3.4 KiB
C++
/* poll.cc. Implements poll(2) via usage of select(2) call.
|
|
|
|
Copyright 2000, 2001, 2002 Red Hat, Inc.
|
|
|
|
This file is part of Cygwin.
|
|
|
|
This software is a copyrighted work licensed under the terms of the
|
|
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
|
|
details. */
|
|
|
|
#define __INSIDE_CYGWIN_NET__
|
|
|
|
#define FD_SETSIZE 16384 // lots of fds
|
|
#include "winsup.h"
|
|
#include <sys/time.h>
|
|
#include <sys/poll.h>
|
|
#include <sys/socket.h>
|
|
#include <stdlib.h>
|
|
#define USE_SYS_TYPES_FD_SET
|
|
#include <winsock2.h>
|
|
#include "cygerrno.h"
|
|
#include "security.h"
|
|
#include "path.h"
|
|
#include "fhandler.h"
|
|
#include "dtable.h"
|
|
#include "cygheap.h"
|
|
#include "sigproc.h"
|
|
|
|
extern "C" int
|
|
poll (struct pollfd *fds, unsigned int nfds, int timeout)
|
|
{
|
|
int max_fd = 0;
|
|
fd_set *read_fds, *write_fds, *except_fds;
|
|
struct timeval tv = { timeout / 1000, (timeout % 1000) * 1000 };
|
|
|
|
for (unsigned int i = 0; i < nfds; ++i)
|
|
if (fds[i].fd > max_fd)
|
|
max_fd = fds[i].fd;
|
|
|
|
size_t fds_size = howmany (max_fd + 1, NFDBITS) * sizeof (fd_mask);
|
|
|
|
read_fds = (fd_set *) alloca (fds_size);
|
|
write_fds = (fd_set *) alloca (fds_size);
|
|
except_fds = (fd_set *) alloca (fds_size);
|
|
|
|
if (!read_fds || !write_fds || !except_fds)
|
|
{
|
|
set_errno (ENOMEM);
|
|
return -1;
|
|
}
|
|
|
|
memset (read_fds, 0, fds_size);
|
|
memset (write_fds, 0, fds_size);
|
|
memset (except_fds, 0, fds_size);
|
|
|
|
int invalid_fds = 0;
|
|
for (unsigned int i = 0; i < nfds; ++i)
|
|
{
|
|
fds[i].revents = 0;
|
|
if (!cygheap->fdtab.not_open (fds[i].fd))
|
|
{
|
|
if (fds[i].events & POLLIN)
|
|
FD_SET(fds[i].fd, read_fds);
|
|
if (fds[i].events & POLLOUT)
|
|
FD_SET(fds[i].fd, write_fds);
|
|
if (fds[i].events & POLLPRI)
|
|
FD_SET(fds[i].fd, except_fds);
|
|
}
|
|
else if (fds[i].fd >= 0)
|
|
{
|
|
++invalid_fds;
|
|
fds[i].revents = POLLNVAL;
|
|
}
|
|
}
|
|
|
|
if (invalid_fds)
|
|
return invalid_fds;
|
|
|
|
int ret = cygwin_select (max_fd + 1, read_fds, write_fds, except_fds, timeout < 0 ? NULL : &tv);
|
|
|
|
if (ret > 0)
|
|
for (unsigned int i = 0; i < nfds; ++i)
|
|
{
|
|
if (fds[i].fd >= 0)
|
|
{
|
|
if (cygheap->fdtab.not_open (fds[i].fd))
|
|
fds[i].revents = POLLHUP;
|
|
else
|
|
{
|
|
if (FD_ISSET(fds[i].fd, read_fds))
|
|
{
|
|
char peek[1];
|
|
fhandler_socket *sock =
|
|
cygheap->fdtab[fds[i].fd]->is_socket ();
|
|
if (!sock)
|
|
fds[i].revents |= POLLIN;
|
|
else
|
|
{
|
|
/* The following action can change errno. We have to
|
|
reset it to it's old value. */
|
|
int old_errno = get_errno ();
|
|
switch (sock->recvfrom (peek, sizeof (peek), MSG_PEEK,
|
|
NULL, NULL))
|
|
{
|
|
case -1: /* Something weird happened */
|
|
/* When select returns that data is available,
|
|
that could mean that the socket is in
|
|
listen mode and a client tries to connect.
|
|
Unfortunately, recvfrom() doesn't make much
|
|
sense then. It returns WSAENOTCONN in that
|
|
case. Since that's not actually an error,
|
|
we must not set POLLERR but POLLIN. */
|
|
if (WSAGetLastError () != WSAENOTCONN)
|
|
fds[i].revents |= POLLERR;
|
|
else
|
|
fds[i].revents |= POLLIN;
|
|
break;
|
|
case 0: /* Closed on the read side. */
|
|
fds[i].revents |= POLLHUP;
|
|
break;
|
|
default:
|
|
fds[i].revents |= POLLIN;
|
|
break;
|
|
}
|
|
set_errno (old_errno);
|
|
}
|
|
}
|
|
if (FD_ISSET(fds[i].fd, write_fds))
|
|
fds[i].revents |= POLLOUT;
|
|
if (FD_ISSET(fds[i].fd, except_fds))
|
|
fds[i].revents |= POLLPRI;
|
|
}
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|