* poll.cc: Allow any descriptor and any number of descriptors.

Allocate fd_set struct sdynamically.
This commit is contained in:
Corinna Vinschen 2000-08-11 20:34:24 +00:00
parent bbda7ca078
commit 427b6d036e
2 changed files with 39 additions and 20 deletions

View File

@ -1,3 +1,8 @@
Fri Aug 11 14:47:00 2000 Corinna Vinschen <corinna@vinschen.de>
* poll.cc: Allow any descriptor and any number of descriptors.
Allocate fd_set struct sdynamically.
Fri Aug 11 14:47:00 2000 Corinna Vinschen <corinna@vinschen.de>
* poll.cc: Add bounds checking for file descriptors. Return POLLNVAL

View File

@ -8,44 +8,58 @@
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include <sys/poll.h>
#include <errno.h>
#include "winsup.h"
extern "C"
int
poll (struct pollfd *fds, unsigned int nfds, int timeout)
{
int max_fd = 0;
fd_set open_fds, read_fds, write_fds, except_fds;
fd_set *open_fds, *read_fds, *write_fds, *except_fds;
struct timeval tv = { timeout / 1000, (timeout % 1000) * 1000 };
FD_ZERO (&open_fds);
FD_ZERO (&read_fds);
FD_ZERO (&write_fds);
FD_ZERO (&except_fds);
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);
open_fds = (fd_set *) alloca (fds_size);
read_fds = (fd_set *) alloca (fds_size);
write_fds = (fd_set *) alloca (fds_size);
except_fds = (fd_set *) alloca (fds_size);
if (!open_fds || !read_fds || !write_fds || !except_fds)
{
set_errno (ENOMEM);
return -1;
}
memset (open_fds, 0, fds_size);
memset (read_fds, 0, fds_size);
memset (write_fds, 0, fds_size);
memset (except_fds, 0, fds_size);
for (unsigned int i = 0; i < nfds; ++i)
if (fds[i].fd < FD_SETSIZE
&& !dtable.not_open (fds[i].fd))
if (!dtable.not_open (fds[i].fd))
{
FD_SET (fds[i].fd, &open_fds);
FD_SET (fds[i].fd, open_fds);
if (fds[i].events & POLLIN)
FD_SET (fds[i].fd, &read_fds);
FD_SET (fds[i].fd, read_fds);
if (fds[i].events & POLLOUT)
FD_SET (fds[i].fd, &write_fds);
FD_SET (fds[i].fd, write_fds);
if (fds[i].events & POLLPRI)
FD_SET (fds[i].fd, &except_fds);
if (fds[i].fd > max_fd)
max_fd = fds[i].fd;
FD_SET (fds[i].fd, except_fds);
}
int ret = cygwin_select (max_fd + 1, &read_fds, &write_fds, &except_fds,
int ret = cygwin_select (max_fd + 1, read_fds, write_fds, except_fds,
timeout < 0 ? NULL : &tv);
for (unsigned int i = 0; i < nfds; ++i)
{
if (fds[i].fd >= FD_SETSIZE
|| !FD_ISSET (fds[i].fd, &open_fds))
if (!FD_ISSET (fds[i].fd, open_fds))
fds[i].revents = POLLNVAL;
else if (dtable.not_open(fds[i].fd))
fds[i].revents = POLLHUP;
@ -54,11 +68,11 @@ poll (struct pollfd *fds, unsigned int nfds, int timeout)
else
{
fds[i].revents = 0;
if (FD_ISSET (fds[i].fd, &read_fds))
if (FD_ISSET (fds[i].fd, read_fds))
fds[i].revents |= POLLIN;
if (FD_ISSET (fds[i].fd, &write_fds))
if (FD_ISSET (fds[i].fd, write_fds))
fds[i].revents |= POLLOUT;
if (FD_ISSET (fds[i].fd, &except_fds))
if (FD_ISSET (fds[i].fd, except_fds))
fds[i].revents |= POLLPRI;
}
}