--- /dev/null
+/* Emulation for poll(2)
+ Contributed by Paolo Bonzini.
+
+ Copyright 2001-2003, 2006-2010 Free Software Foundation, Inc.
+
+ This file is part of gnulib.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+/* Tell gcc not to warn about the (nfd < 0) tests, below. */
+#if (__GNUC__ == 4 && 3 <= __GNUC_MINOR__) || 4 < __GNUC__
+# pragma GCC diagnostic ignored "-Wtype-limits"
+#endif
+
+#include <config.h>
+#include <alloca.h>
+
+#include <sys/types.h>
+#include "poll.h"
+#include <errno.h>
+#include <limits.h>
+#include <assert.h>
+
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+# define WIN32_NATIVE
+# include <winsock2.h>
+# include <windows.h>
+# include <io.h>
+# include <stdio.h>
+# include <conio.h>
+#else
+# include <sys/time.h>
+# include <sys/socket.h>
+# include <sys/select.h>
+# include <unistd.h>
+#endif
+
+#ifdef HAVE_SYS_IOCTL_H
+# include <sys/ioctl.h>
+#endif
+#ifdef HAVE_SYS_FILIO_H
+# include <sys/filio.h>
+#endif
+
+#include <time.h>
+
+#ifndef INFTIM
+# define INFTIM (-1)
+#endif
+
+/* BeOS does not have MSG_PEEK. */
+#ifndef MSG_PEEK
+# define MSG_PEEK 0
+#endif
+
+#ifdef WIN32_NATIVE
+
+#define IsConsoleHandle(h) (((long) (h) & 3) == 3)
+
+static BOOL
+IsSocketHandle (HANDLE h)
+{
+ WSANETWORKEVENTS ev;
+
+ if (IsConsoleHandle (h))
+ return FALSE;
+
+ /* Under Wine, it seems that getsockopt returns 0 for pipes too.
+ WSAEnumNetworkEvents instead distinguishes the two correctly. */
+ ev.lNetworkEvents = 0xDEADBEEF;
+ WSAEnumNetworkEvents ((SOCKET) h, NULL, &ev);
+ return ev.lNetworkEvents != 0xDEADBEEF;
+}
+
+/* Declare data structures for ntdll functions. */
+typedef struct _FILE_PIPE_LOCAL_INFORMATION {
+ ULONG NamedPipeType;
+ ULONG NamedPipeConfiguration;
+ ULONG MaximumInstances;
+ ULONG CurrentInstances;
+ ULONG InboundQuota;
+ ULONG ReadDataAvailable;
+ ULONG OutboundQuota;
+ ULONG WriteQuotaAvailable;
+ ULONG NamedPipeState;
+ ULONG NamedPipeEnd;
+} FILE_PIPE_LOCAL_INFORMATION, *PFILE_PIPE_LOCAL_INFORMATION;
+
+typedef struct _IO_STATUS_BLOCK
+{
+ union {
+ DWORD Status;
+ PVOID Pointer;
+ } u;
+ ULONG_PTR Information;
+} IO_STATUS_BLOCK, *PIO_STATUS_BLOCK;
+
+typedef enum _FILE_INFORMATION_CLASS {
+ FilePipeLocalInformation = 24
+} FILE_INFORMATION_CLASS, *PFILE_INFORMATION_CLASS;
+
+typedef DWORD (WINAPI *PNtQueryInformationFile)
+ (HANDLE, IO_STATUS_BLOCK *, VOID *, ULONG, FILE_INFORMATION_CLASS);
+
+# ifndef PIPE_BUF
+# define PIPE_BUF 512
+# endif
+
+/* Compute revents values for file handle H. If some events cannot happen
+ for the handle, eliminate them from *P_SOUGHT. */
+
+static int
+win32_compute_revents (HANDLE h, int *p_sought)
+{
+ int i, ret, happened;
+ INPUT_RECORD *irbuffer;
+ DWORD avail, nbuffer;
+ BOOL bRet;
+ IO_STATUS_BLOCK iosb;
+ FILE_PIPE_LOCAL_INFORMATION fpli;
+ static PNtQueryInformationFile NtQueryInformationFile;
+ static BOOL once_only;
+
+ switch (GetFileType (h))
+ {
+ case FILE_TYPE_PIPE:
+ if (!once_only)
+ {
+ NtQueryInformationFile = (PNtQueryInformationFile)
+ GetProcAddress (GetModuleHandle ("ntdll.dll"),
+ "NtQueryInformationFile");
+ once_only = TRUE;
+ }
+
+ happened = 0;
+ if (PeekNamedPipe (h, NULL, 0, NULL, &avail, NULL) != 0)
+ {
+ if (avail)
+ happened |= *p_sought & (POLLIN | POLLRDNORM);
+ }
+ else if (GetLastError () == ERROR_BROKEN_PIPE)
+ happened |= POLLHUP;
+
+ else
+ {
+ /* It was the write-end of the pipe. Check if it is writable.
+ If NtQueryInformationFile fails, optimistically assume the pipe is
+ writable. This could happen on Win9x, where NtQueryInformationFile
+ is not available, or if we inherit a pipe that doesn't permit
+ FILE_READ_ATTRIBUTES access on the write end (I think this should
+ not happen since WinXP SP2; WINE seems fine too). Otherwise,
+ ensure that enough space is available for atomic writes. */
+ memset (&iosb, 0, sizeof (iosb));
+ memset (&fpli, 0, sizeof (fpli));
+
+ if (!NtQueryInformationFile
+ || NtQueryInformationFile (h, &iosb, &fpli, sizeof (fpli),
+ FilePipeLocalInformation)
+ || fpli.WriteQuotaAvailable >= PIPE_BUF
+ || (fpli.OutboundQuota < PIPE_BUF &&
+ fpli.WriteQuotaAvailable == fpli.OutboundQuota))
+ happened |= *p_sought & (POLLOUT | POLLWRNORM | POLLWRBAND);
+ }
+ return happened;
+
+ case FILE_TYPE_CHAR:
+ ret = WaitForSingleObject (h, 0);
+ if (!IsConsoleHandle (h))
+ return ret == WAIT_OBJECT_0 ? *p_sought & ~(POLLPRI | POLLRDBAND) : 0;
+
+ nbuffer = avail = 0;
+ bRet = GetNumberOfConsoleInputEvents (h, &nbuffer);
+ if (bRet)
+ {
+ /* Input buffer. */
+ *p_sought &= POLLIN | POLLRDNORM;
+ if (nbuffer == 0)
+ return POLLHUP;
+ if (!*p_sought)
+ return 0;
+
+ irbuffer = (INPUT_RECORD *) alloca (nbuffer * sizeof (INPUT_RECORD));
+ bRet = PeekConsoleInput (h, irbuffer, nbuffer, &avail);
+ if (!bRet || avail == 0)
+ return POLLHUP;
+
+ for (i = 0; i < avail; i++)
+ if (irbuffer[i].EventType == KEY_EVENT)
+ return *p_sought;
+ return 0;
+ }
+ else
+ {
+ /* Screen buffer. */
+ *p_sought &= POLLOUT | POLLWRNORM | POLLWRBAND;
+ return *p_sought;
+ }
+
+ default:
+ ret = WaitForSingleObject (h, 0);
+ if (ret == WAIT_OBJECT_0)
+ return *p_sought & ~(POLLPRI | POLLRDBAND);
+
+ return *p_sought & (POLLOUT | POLLWRNORM | POLLWRBAND);
+ }
+}
+
+/* Convert fd_sets returned by select into revents values. */
+
+static int
+win32_compute_revents_socket (SOCKET h, int sought, long lNetworkEvents)
+{
+ int happened = 0;
+
+ if ((lNetworkEvents & (FD_READ | FD_ACCEPT | FD_CLOSE)) == FD_ACCEPT)
+ happened |= (POLLIN | POLLRDNORM) & sought;
+
+ else if (lNetworkEvents & (FD_READ | FD_ACCEPT | FD_CLOSE))
+ {
+ int r, error;
+
+ char data[64];
+ WSASetLastError (0);
+ r = recv (h, data, sizeof (data), MSG_PEEK);
+ error = WSAGetLastError ();
+ WSASetLastError (0);
+
+ if (r > 0 || error == WSAENOTCONN)
+ happened |= (POLLIN | POLLRDNORM) & sought;
+
+ /* Distinguish hung-up sockets from other errors. */
+ else if (r == 0 || error == WSAESHUTDOWN || error == WSAECONNRESET
+ || error == WSAECONNABORTED || error == WSAENETRESET)
+ happened |= POLLHUP;
+
+ else
+ happened |= POLLERR;
+ }
+
+ if (lNetworkEvents & (FD_WRITE | FD_CONNECT))
+ happened |= (POLLOUT | POLLWRNORM | POLLWRBAND) & sought;
+
+ if (lNetworkEvents & FD_OOB)
+ 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 = 0;
+ 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 WIN32_NATIVE
+ fd_set rfds, wfds, efds;
+ struct timeval tv;
+ struct timeval *ptv;
+ int maxfd, rc;
+ nfds_t i;
+
+# ifdef _SC_OPEN_MAX
+ static int sc_open_max = -1;
+
+ if (nfd < 0
+ || (nfd > sc_open_max
+ && (sc_open_max != -1
+ || nfd > (sc_open_max = sysconf (_SC_OPEN_MAX)))))
+ {
+ errno = EINVAL;
+ return -1;
+ }
+# else /* !_SC_OPEN_MAX */
+# ifdef OPEN_MAX
+ if (nfd < 0 || nfd > OPEN_MAX)
+ {
+ errno = EINVAL;
+ return -1;
+ }
+# endif /* OPEN_MAX -- else, no check is needed */
+# endif /* !_SC_OPEN_MAX */
+
+ /* EFAULT is not necessary to implement, but let's do it in the
+ simplest case. */
+ if (!pfd)
+ {
+ errno = EFAULT;
+ return -1;
+ }
+
+ /* convert timeout number into a timeval structure */
+ if (timeout == 0)
+ {
+ ptv = &tv;
+ ptv->tv_sec = 0;
+ ptv->tv_usec = 0;
+ }
+ else if (timeout > 0)
+ {
+ ptv = &tv;
+ ptv->tv_sec = timeout / 1000;
+ ptv->tv_usec = (timeout % 1000) * 1000;
+ }
+ else if (timeout == INFTIM)
+ /* wait forever */
+ ptv = NULL;
+ else
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ /* create fd sets and determine max fd */
+ maxfd = -1;
+ FD_ZERO (&rfds);
+ FD_ZERO (&wfds);
+ FD_ZERO (&efds);
+ for (i = 0; i < nfd; i++)
+ {
+ if (pfd[i].fd < 0)
+ continue;
+
+ if (pfd[i].events & (POLLIN | POLLRDNORM))
+ FD_SET (pfd[i].fd, &rfds);
+
+ /* see select(2): "the only exceptional condition detectable
+ is out-of-band data received on a socket", hence we push
+ POLLWRBAND events onto wfds instead of efds. */
+ if (pfd[i].events & (POLLOUT | POLLWRNORM | POLLWRBAND))
+ FD_SET (pfd[i].fd, &wfds);
+ if (pfd[i].events & (POLLPRI | POLLRDBAND))
+ FD_SET (pfd[i].fd, &efds);
+ if (pfd[i].fd >= maxfd
+ && (pfd[i].events & (POLLIN | POLLOUT | POLLPRI
+ | POLLRDNORM | POLLRDBAND
+ | POLLWRNORM | POLLWRBAND)))
+ {
+ maxfd = pfd[i].fd;
+ if (maxfd > FD_SETSIZE)
+ {
+ errno = EOVERFLOW;
+ return -1;
+ }
+ }
+ }
+
+ /* examine fd sets */
+ rc = select (maxfd + 1, &rfds, &wfds, &efds, ptv);
+ if (rc < 0)
+ return rc;
+
+ /* establish results */
+ rc = 0;
+ for (i = 0; i < nfd; i++)
+ if (pfd[i].fd < 0)
+ pfd[i].revents = 0;
+ else
+ {
+ int happened = compute_revents (pfd[i].fd, pfd[i].events,
+ &rfds, &wfds, &efds);
+ if (happened)
+ {
+ pfd[i].revents = happened;
+ rc++;
+ }
+ }
+
+ return rc;
+#else
+ static struct timeval tv0;
+ static HANDLE hEvent;
+ WSANETWORKEVENTS ev;
+ HANDLE h, handle_array[FD_SETSIZE + 2];
+ DWORD ret, wait_timeout, nhandles;
+ fd_set rfds, wfds, xfds;
+ BOOL poll_again;
+ MSG msg;
+ int rc = 0;
+ nfds_t i;
+
+ if (nfd < 0 || timeout < -1)
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ if (!hEvent)
+ hEvent = CreateEvent (NULL, FALSE, FALSE, NULL);
+
+ handle_array[0] = hEvent;
+ nhandles = 1;
+ FD_ZERO (&rfds);
+ FD_ZERO (&wfds);
+ FD_ZERO (&xfds);
+
+ /* Classify socket handles and create fd sets. */
+ for (i = 0; i < nfd; i++)
+ {
+ int sought = pfd[i].events;
+ pfd[i].revents = 0;
+ if (pfd[i].fd < 0)
+ continue;
+ if (!(sought & (POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM | POLLWRBAND
+ | POLLPRI | POLLRDBAND)))
+ continue;
+
+ h = (HANDLE) _get_osfhandle (pfd[i].fd);
+ assert (h != NULL);
+ if (IsSocketHandle (h))
+ {
+ int requested = FD_CLOSE;
+
+ /* see above; socket handles are mapped onto select. */
+ if (sought & (POLLIN | POLLRDNORM))
+ {
+ requested |= FD_READ | FD_ACCEPT;
+ FD_SET ((SOCKET) h, &rfds);
+ }
+ if (sought & (POLLOUT | POLLWRNORM | POLLWRBAND))
+ {
+ requested |= FD_WRITE | FD_CONNECT;
+ FD_SET ((SOCKET) h, &wfds);
+ }
+ if (sought & (POLLPRI | POLLRDBAND))
+ {
+ requested |= FD_OOB;
+ FD_SET ((SOCKET) h, &xfds);
+ }
+
+ if (requested)
+ WSAEventSelect ((SOCKET) h, hEvent, requested);
+ }
+ else
+ {
+ /* Poll now. If we get an event, do not poll again. Also,
+ screen buffer handles are waitable, and they'll block until
+ a character is available. win32_compute_revents eliminates
+ bits for the "wrong" direction. */
+ pfd[i].revents = win32_compute_revents (h, &sought);
+ if (sought)
+ handle_array[nhandles++] = h;
+ if (pfd[i].revents)
+ timeout = 0;
+ }
+ }
+
+ if (select (0, &rfds, &wfds, &xfds, &tv0) > 0)
+ {
+ /* Do MsgWaitForMultipleObjects anyway to dispatch messages, but
+ no need to call select again. */
+ poll_again = FALSE;
+ wait_timeout = 0;
+ }
+ else
+ {
+ poll_again = TRUE;
+ 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 */
+ BOOL bRet;
+ while ((bRet = PeekMessage (&msg, NULL, 0, 0, PM_REMOVE)) != 0)
+ {
+ TranslateMessage (&msg);
+ DispatchMessage (&msg);
+ }
+ }
+ else
+ break;
+ }
+
+ if (poll_again)
+ select (0, &rfds, &wfds, &xfds, &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)
+ continue;
+ if (!(pfd[i].events & (POLLIN | POLLRDNORM |
+ POLLOUT | POLLWRNORM | POLLWRBAND)))
+ continue;
+
+ h = (HANDLE) _get_osfhandle (pfd[i].fd);
+ if (h != handle_array[nhandles])
+ {
+ /* It's a socket. */
+ WSAEnumNetworkEvents ((SOCKET) h, NULL, &ev);
+ WSAEventSelect ((SOCKET) h, 0, 0);
+
+ /* If we're lucky, WSAEnumNetworkEvents already provided a way
+ to distinguish FD_READ and FD_ACCEPT; this saves a recv later. */
+ if (FD_ISSET ((SOCKET) h, &rfds)
+ && !(ev.lNetworkEvents & (FD_READ | FD_ACCEPT)))
+ ev.lNetworkEvents |= FD_READ | FD_ACCEPT;
+ if (FD_ISSET ((SOCKET) h, &wfds))
+ ev.lNetworkEvents |= FD_WRITE | FD_CONNECT;
+ if (FD_ISSET ((SOCKET) h, &xfds))
+ ev.lNetworkEvents |= FD_OOB;
+
+ happened = win32_compute_revents_socket ((SOCKET) h, pfd[i].events,
+ ev.lNetworkEvents);
+ }
+ else
+ {
+ /* Not a socket. */
+ int sought = pfd[i].events;
+ happened = win32_compute_revents (h, &sought);
+ nhandles++;
+ }
+
+ if ((pfd[i].revents |= happened) != 0)
+ rc++;
+ }
+
+ return rc;
+#endif
+}
projects / thirdparty / git.git / commitdiff
