Hi,
a while ago a user of GNU Smalltalk contributed code to run the
emulation of poll in gnulib under Win32. The code was a little hackish,
as it worked by emulating other POSIX system calls "as well as it was
needed" to emulate poll; so I never contributed it to gnulib.
Now, however, I merged that code with the gnulib poll.c in order to
obtain a native poll emulation for Win32 (MinGW). It supports sockets,
console handles, and disk files. Adding named pipes would not be hard,
and can be done later.
However, I don't have any way to test it. It might not even compile, in
fact. Can anybody help?
Thanks,
Paolo
2008-08-18 Paolo Bonzini <[EMAIL PROTECTED]>
* lib/poll.c (win32_compute_revents, win32_compute_revents_socket): New.
(compute_revents): Extract out of poll.
(poll): Add Win32 implementation for MinGW.
diff --git a/lib/poll.c b/lib/poll.c
index 4a62dc1..888757c 100644
--- a/lib/poll.c
+++ b/lib/poll.c
@@ -25,9 +25,18 @@
#include "poll.h"
#include <errno.h>
#include <limits.h>
+
+#ifdef __MSVCRT__
+#include <windows.h>
+#include <winsock2.h>
+#include <io.h>
+#include <stdio.h>
+#include <conio.h>
+#else
#include <sys/socket.h>
#include <sys/select.h>
#include <unistd.h>
+#endif
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
@@ -48,12 +57,144 @@
#define MSG_PEEK 0
#endif
+#ifdef __MSVCRT__
+/* Compute revents values for file handle H. */
+
+static int
+win32_compute_revents (HANDLE h, int sought)
+{
+ int i, ret;
+ INPUT_RECORD *irbuffer;
+ DWORD nevents, nbuffer;
+
+ ret = WaitForSingleObject (h, 0);
+ if (ret != WAIT_OBJECT_0)
+ return sought & (POLLOUT | POLLWRNORM | POLLWRBAND);
+
+ if (GetFileType (h) != FILE_TYPE_CHAR)
+ return sought & ~(POLLPRI | POLLRDBAND);
+
+ nbuffer = nevents = 0;
+ bRet = GetNumberOfConsoleInputEvents (h, &nbuffer);
+ if (!bRet || nbuffer == 0)
+ return POLLHUP;
+
+ irbuffer = (INPUT_RECORD *) alloca (nbuffer * sizeof (INPUT_RECORD));
+ bRet = PeekConsoleInput (h, irbuffer, nbuffer, &nevents);
+ if (!bRet || nevents == 0)
+ return POLLHUP;
+
+ for (i = 0; i < nevents; i++)
+ if (irbuffer[i].EventType == KEY_EVENT)
+ return sought & ~(POLLPRI | POLLRDBAND);
+
+ return sought & (POLLOUT | POLLWRNORM | POLLWRBAND);
+}
+
+/* Convert fd_sets returned by select into revents values. */
+
+static int
+win32_compute_revents_socket (SOCKET h, int sought,
+ fd_set *rfds, fd_set *wfds, fd_set *efds)
+{
+ int happened = 0;
+
+ if (FD_ISSET (h, rfds))
+ {
+ int r, error;
+
+ char data[64];
+ WSASetLastError (0);
+ r = recv (h, data, sizeof (data), MSG_PEEK);
+ error = WSAGetLastError ();
+ WSASetLastError (0);
+
+ if (r == 0)
+ happened |= POLLHUP;
+
+ /* If the event happened on an unconnected server socket,
+ that's fine. */
+ else if (r > 0 || ( /* (r == -1) && */ error == ENOTCONN))
+ happened |= (POLLIN | POLLRDNORM) & sought;
+
+ /* Distinguish hung-up sockets from other errors. */
+ else if (error == WSAESHUTDOWN || error == WSAECONNRESET
+ || error == WSAECONNABORTED || error == WSAENETRESET)
+ happened |= POLLHUP;
+
+ else
+ happened |= POLLERR;
+ }
+
+ if (FD_ISSET (h, wfds))
+ happened |= (POLLOUT | POLLWRNORM | POLLWRBAND) & sought;
+
+ if (FD_ISSET (h, efds))
+ happened |= (POLLPRI | POLLRDBAND) & sought;
+
+ return happened;
+}
+
+#else /* !MinGW */
+
+/* Convert select(2) returned fd_sets into poll(2) revents values. */
+static int
+compute_revents (int fd, int sought, fd_set *rfds, fd_set *wfds, fd_set *efds)
+{
+ int happened;
+ if (FD_ISSET (fd, rfds))
+ {
+ int r;
+ int socket_errno;
+
+#if defined __MACH__ && defined __APPLE__
+ /* There is a bug in Mac OS X that causes it to ignore MSG_PEEK
+ for some kinds of descriptors. Detect if this descriptor is a
+ connected socket, a server socket, or something else using a
+ 0-byte recv, and use ioctl(2) to detect POLLHUP. */
+ r = recv (fd, NULL, 0, MSG_PEEK);
+ socket_errno = (r < 0) ? errno : 0;
+ if (r == 0 || socket_errno == ENOTSOCK)
+ ioctl (fd, FIONREAD, &r);
+#else
+ char data[64];
+ r = recv (fd, data, sizeof (data), MSG_PEEK);
+ socket_errno = (r < 0) ? errno : 0;
+#endif
+ if (r == 0)
+ happened |= POLLHUP;
+
+ /* If the event happened on an unconnected server socket,
+ that's fine. */
+ else if (r > 0 || ( /* (r == -1) && */ socket_errno == ENOTCONN))
+ happened |= (POLLIN | POLLRDNORM) & sought;
+
+ /* Distinguish hung-up sockets from other errors. */
+ else if (socket_errno == ESHUTDOWN || socket_errno == ECONNRESET
+ || socket_errno == ECONNABORTED || socket_errno == ENETRESET)
+ happened |= POLLHUP;
+
+ else
+ happened |= POLLERR;
+ }
+
+ if (FD_ISSET (fd, wfds))
+ happened |= (POLLOUT | POLLWRNORM | POLLWRBAND) & sought;
+
+ if (FD_ISSET (fd, efds))
+ happened |= (POLLPRI | POLLRDBAND) & sought;
+
+ return happened;
+}
+#endif /* !MinGW */
+
int
poll (pfd, nfd, timeout)
struct pollfd *pfd;
nfds_t nfd;
int timeout;
{
+#ifndef __MSVCRT__
fd_set rfds, wfds, efds;
struct timeval tv;
struct timeval *ptv;
@@ -162,55 +303,152 @@ poll (pfd, nfd, timeout)
pfd[i].revents = 0;
else
{
- int happened = 0, sought = pfd[i].events;
- if (FD_ISSET (pfd[i].fd, &rfds))
+ int happened = compute_revents (pfd[i].fd, pfd[i].events,
+ &rfds, &wfds, &efds);
+ if (happened)
{
- int r;
- int socket_errno;
+ pfd[i].revents = happened;
+ rc++;
+ }
+ }
-#if defined __MACH__ && defined __APPLE__
- /* There is a bug in Mac OS X that causes it to ignore MSG_PEEK
- for some kinds of descriptors. Detect if this descriptor is a
- connected socket, a server socket, or something else using a
- 0-byte recv, and use ioctl(2) to detect POLLHUP. */
- r = recv (pfd[i].fd, NULL, 0, MSG_PEEK);
- socket_errno = (r < 0) ? errno : 0;
- if (r == 0 || socket_errno == ENOTSOCK)
- ioctl(pfd[i].fd, FIONREAD, &r);
+ return rc;
#else
- char data[64];
- r = recv (pfd[i].fd, data, sizeof (data), MSG_PEEK);
- socket_errno = (r < 0) ? errno : 0;
-#endif
- if (r == 0)
- happened |= POLLHUP;
+ fd_set rfds, wfds, efds;
+ static struct timeval tv0;
+ struct timeval tv = { 0, 0 };
+ struct timeval *ptv;
+ static HANDLE hEvent;
+ HANDLE handle_array[FD_SET_SIZE + 1];
+ DWORD ret, wait_timeout, nhandles;
+ int nsock;
+ BOOL bRet;
+ MSG msg;
+ char sockbuf[256];
+ int rc;
+ nfds_t i;
- /* If the event happened on an unconnected server socket,
- that's fine. */
- else if (r > 0 || ( /* (r == -1) && */ socket_errno == ENOTCONN))
- happened |= (POLLIN | POLLRDNORM) & sought;
+ if (!hEvent)
+ hEvent = CreateEvent (NULL, FALSE, FALSE, NULL);
- /* Distinguish hung-up sockets from other errors. */
- else if (socket_errno == ESHUTDOWN || socket_errno == ECONNRESET
- || socket_errno == ECONNABORTED || socket_errno ==
ENETRESET)
- happened |= POLLHUP;
+ handle_array[0] = hEvent;
+ nhandles = 1;
- else
- happened |= POLLERR;
- }
+ if (nfd < 0 || nfd > FD_SET_SIZE)
+ {
+ errno = EINVAL;
+ return -1;
+ }
- if (FD_ISSET (pfd[i].fd, &wfds))
- happened |= (POLLOUT | POLLWRNORM | POLLWRBAND) & sought;
+ /* Classify socket handles and create fd sets. */
+ FD_ZERO (&rfds);
+ FD_ZERO (&wfds);
+ FD_ZERO (&efds);
+ for (i = 0; i < nfd; i++)
+ {
+ if (pfd[i].fd < 0)
+ continue;
- if (FD_ISSET (pfd[i].fd, &efds))
- happened |= (POLLPRI | POLLRDBAND) & sought;
+ h = (HANDLE) _get_osfhandle (i);
+ assert (h != NULL);
+ optlen = sizeof(sockbuf);
+ if ((getsockopt ((SOCKET) h, SOL_SOCKET, SO_TYPE, sockbuf, &optlen)
+ != SOCKET_ERROR)
+ || WSAGetLastError() != WSAENOTSOCK)
+ {
+ int ev = 0;
- if (happened)
- {
- pfd[i].revents = happened;
- rc++;
- }
- }
+ /* see above; socket handles are mapped onto select. */
+ if (pfd[i].events & (POLLIN | POLLRDNORM))
+ {
+ FD_SET (pfd[i].fd, &rfds);
+ ev |= FD_READ | FD_ACCEPT;
+ }
+ if (pfd[i].events & (POLLOUT | POLLWRNORM | POLLWRBAND))
+ {
+ FD_SET (pfd[i].fd, &wfds);
+ ev |= FD_WRITE | FD_CONNECT;
+ }
+ if (pfd[i].events & (POLLPRI | POLLRDBAND))
+ {
+ FD_SET (pfd[i].fd, &efds);
+ ev |= FD_OOB;
+ }
+ if (ev)
+ {
+ WSAEventSelect ((SOCKET) h, hEvent, ev);
+ nsock++;
+ }
+ }
+ else
+ {
+ if (pfd[i].events & (POLLIN | POLLRDNORM |
+ POLLOUT | POLLWRNORM | POLLWRBAND))
+ handle_array[nhandles++] = h;
+ }
+ }
+
+ if (timeout == INFTIM)
+ wait_timeout = INFINITE;
+ else
+ wait_timeout = timeout;
+
+ for (;;)
+ {
+ ret = MsgWaitForMultipleObjects (nhandles, handle_array, FALSE,
+ wait_timeout, QS_ALLINPUT);
+
+ if (ret == WAIT_OBJECT_0 + nhandles)
+ {
+ /* new input of some other kind */
+ while ((bRet = PeekMessage (&msg, NULL, 0, 0, PM_REMOVE)) != 0)
+ {
+ TranslateMessage (&msg);
+ DispatchMessage (&msg);
+ }
+ }
+ else
+ break;
+ }
+
+ /* Now check if the sockets have some event set. */
+ select (nsock + 1, rfds, wfds, efds, &tv0);
+
+ /* Place a sentinel at the end of the array. */
+ handle_array[nhandles] = NULL;
+ nhandles = 1;
+ for (i = 0; i < nfd; i++)
+ {
+ int happened;
+
+ if (pfd[i].fd < 0)
+ {
+ pfd[i].revents = 0;
+ continue;
+ }
+
+ h = (HANDLE) _get_osfhandle (i);
+ if (h != handle_array[nhandles])
+ {
+ /* It's a socket. */
+ WSAEventSelect (h, 0, 0);
+ happened = win32_compute_revents_socket ((SOCKET) h, pfd[i].events,
+ &rfds, &wfds, &efds);
+ }
+ else
+ {
+ /* Not a socket. */
+ nhandles++;
+ happened = win32_compute_revents (h, pfd[i].events);
+ }
+
+ if (happened)
+ {
+ pfd[i].revents = happened;
+ rc++;
+ }
+ }
return rc;
+#endif
}
