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-rw-r--r--gl/lib/select.c595
1 files changed, 595 insertions, 0 deletions
diff --git a/gl/lib/select.c b/gl/lib/select.c
new file mode 100644
index 0000000..e35746b
--- /dev/null
+++ b/gl/lib/select.c
@@ -0,0 +1,595 @@
+/* Emulation for select(2)
+ Contributed by Paolo Bonzini.
+
+ Copyright 2008-2020 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 3, 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, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <alloca.h>
+#include <assert.h>
+
+#if defined _WIN32 && ! defined __CYGWIN__
+/* Native Windows. */
+
+#include <sys/types.h>
+#include <errno.h>
+#include <limits.h>
+
+#include <winsock2.h>
+#include <windows.h>
+#include <io.h>
+#include <stdio.h>
+#include <conio.h>
+#include <time.h>
+
+/* Get the overridden 'struct timeval'. */
+#include <sys/time.h>
+
+#if GNULIB_MSVC_NOTHROW
+# include "msvc-nothrow.h"
+#else
+# include <io.h>
+#endif
+
+#undef select
+
+/* Don't assume that UNICODE is not defined. */
+#undef GetModuleHandle
+#define GetModuleHandle GetModuleHandleA
+#undef PeekConsoleInput
+#define PeekConsoleInput PeekConsoleInputA
+#undef CreateEvent
+#define CreateEvent CreateEventA
+#undef PeekMessage
+#define PeekMessage PeekMessageA
+#undef DispatchMessage
+#define DispatchMessage DispatchMessageA
+
+/* Avoid warnings from gcc -Wcast-function-type. */
+#define GetProcAddress \
+ (void *) GetProcAddress
+
+struct bitset {
+ unsigned char in[FD_SETSIZE / CHAR_BIT];
+ unsigned char out[FD_SETSIZE / CHAR_BIT];
+};
+
+/* 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
+
+static BOOL IsConsoleHandle (HANDLE h)
+{
+ DWORD mode;
+ return GetConsoleMode (h, &mode) != 0;
+}
+
+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;
+}
+
+/* Compute output fd_sets for libc descriptor FD (whose Windows handle is
+ H). */
+
+static int
+windows_poll_handle (HANDLE h, int fd,
+ struct bitset *rbits,
+ struct bitset *wbits,
+ struct bitset *xbits)
+{
+ BOOL read, write, except;
+ int i, ret;
+ INPUT_RECORD *irbuffer;
+ DWORD avail, nbuffer;
+ BOOL bRet;
+ IO_STATUS_BLOCK iosb;
+ FILE_PIPE_LOCAL_INFORMATION fpli;
+ static PNtQueryInformationFile NtQueryInformationFile;
+ static BOOL once_only;
+
+ read = write = except = FALSE;
+ switch (GetFileType (h))
+ {
+ case FILE_TYPE_DISK:
+ read = TRUE;
+ write = TRUE;
+ break;
+
+ case FILE_TYPE_PIPE:
+ if (!once_only)
+ {
+ NtQueryInformationFile = (PNtQueryInformationFile)
+ GetProcAddress (GetModuleHandle ("ntdll.dll"),
+ "NtQueryInformationFile");
+ once_only = TRUE;
+ }
+
+ if (PeekNamedPipe (h, NULL, 0, NULL, &avail, NULL) != 0)
+ {
+ if (avail)
+ read = TRUE;
+ }
+ else if (GetLastError () == ERROR_BROKEN_PIPE)
+ ;
+
+ 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 Windows 9x, 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 Windows XP 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))
+ write = TRUE;
+ }
+ break;
+
+ case FILE_TYPE_CHAR:
+ write = TRUE;
+ if (!(rbits->in[fd / CHAR_BIT] & (1 << (fd & (CHAR_BIT - 1)))))
+ break;
+
+ ret = WaitForSingleObject (h, 0);
+ if (ret == WAIT_OBJECT_0)
+ {
+ if (!IsConsoleHandle (h))
+ {
+ read = TRUE;
+ break;
+ }
+
+ nbuffer = avail = 0;
+ bRet = GetNumberOfConsoleInputEvents (h, &nbuffer);
+
+ /* Screen buffers handles are filtered earlier. */
+ assert (bRet);
+ if (nbuffer == 0)
+ {
+ except = TRUE;
+ break;
+ }
+
+ irbuffer = (INPUT_RECORD *) alloca (nbuffer * sizeof (INPUT_RECORD));
+ bRet = PeekConsoleInput (h, irbuffer, nbuffer, &avail);
+ if (!bRet || avail == 0)
+ {
+ except = TRUE;
+ break;
+ }
+
+ for (i = 0; i < avail; i++)
+ if (irbuffer[i].EventType == KEY_EVENT)
+ read = TRUE;
+ }
+ break;
+
+ default:
+ ret = WaitForSingleObject (h, 0);
+ write = TRUE;
+ if (ret == WAIT_OBJECT_0)
+ read = TRUE;
+
+ break;
+ }
+
+ ret = 0;
+ if (read && (rbits->in[fd / CHAR_BIT] & (1 << (fd & (CHAR_BIT - 1)))))
+ {
+ rbits->out[fd / CHAR_BIT] |= (1 << (fd & (CHAR_BIT - 1)));
+ ret++;
+ }
+
+ if (write && (wbits->in[fd / CHAR_BIT] & (1 << (fd & (CHAR_BIT - 1)))))
+ {
+ wbits->out[fd / CHAR_BIT] |= (1 << (fd & (CHAR_BIT - 1)));
+ ret++;
+ }
+
+ if (except && (xbits->in[fd / CHAR_BIT] & (1 << (fd & (CHAR_BIT - 1)))))
+ {
+ xbits->out[fd / CHAR_BIT] |= (1 << (fd & (CHAR_BIT - 1)));
+ ret++;
+ }
+
+ return ret;
+}
+
+int
+rpl_select (int nfds, fd_set *rfds, fd_set *wfds, fd_set *xfds,
+ struct timeval *timeout)
+#undef timeval
+{
+ static struct timeval tv0;
+ static HANDLE hEvent;
+ HANDLE h, handle_array[FD_SETSIZE + 2];
+ fd_set handle_rfds, handle_wfds, handle_xfds;
+ struct bitset rbits, wbits, xbits;
+ unsigned char anyfds_in[FD_SETSIZE / CHAR_BIT];
+ DWORD ret, wait_timeout, nhandles, nsock, nbuffer;
+ MSG msg;
+ int i, fd, rc;
+ clock_t tend;
+
+ if (nfds > FD_SETSIZE)
+ nfds = FD_SETSIZE;
+
+ if (!timeout)
+ wait_timeout = INFINITE;
+ else
+ {
+ wait_timeout = timeout->tv_sec * 1000 + timeout->tv_usec / 1000;
+
+ /* select is also used as a portable usleep. */
+ if (!rfds && !wfds && !xfds)
+ {
+ Sleep (wait_timeout);
+ return 0;
+ }
+ }
+
+ if (!hEvent)
+ hEvent = CreateEvent (NULL, FALSE, FALSE, NULL);
+
+ handle_array[0] = hEvent;
+ nhandles = 1;
+ nsock = 0;
+
+ /* Copy descriptors to bitsets. At the same time, eliminate
+ bits in the "wrong" direction for console input buffers
+ and screen buffers, because screen buffers are waitable
+ and they will block until a character is available. */
+ memset (&rbits, 0, sizeof (rbits));
+ memset (&wbits, 0, sizeof (wbits));
+ memset (&xbits, 0, sizeof (xbits));
+ memset (anyfds_in, 0, sizeof (anyfds_in));
+ if (rfds)
+ for (i = 0; i < rfds->fd_count; i++)
+ {
+ fd = rfds->fd_array[i];
+ h = (HANDLE) _get_osfhandle (fd);
+ if (IsConsoleHandle (h)
+ && !GetNumberOfConsoleInputEvents (h, &nbuffer))
+ continue;
+
+ rbits.in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1));
+ anyfds_in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1));
+ }
+ else
+ rfds = (fd_set *) alloca (sizeof (fd_set));
+
+ if (wfds)
+ for (i = 0; i < wfds->fd_count; i++)
+ {
+ fd = wfds->fd_array[i];
+ h = (HANDLE) _get_osfhandle (fd);
+ if (IsConsoleHandle (h)
+ && GetNumberOfConsoleInputEvents (h, &nbuffer))
+ continue;
+
+ wbits.in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1));
+ anyfds_in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1));
+ }
+ else
+ wfds = (fd_set *) alloca (sizeof (fd_set));
+
+ if (xfds)
+ for (i = 0; i < xfds->fd_count; i++)
+ {
+ fd = xfds->fd_array[i];
+ xbits.in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1));
+ anyfds_in[fd / CHAR_BIT] |= 1 << (fd & (CHAR_BIT - 1));
+ }
+ else
+ xfds = (fd_set *) alloca (sizeof (fd_set));
+
+ /* Zero all the fd_sets, including the application's. */
+ FD_ZERO (rfds);
+ FD_ZERO (wfds);
+ FD_ZERO (xfds);
+ FD_ZERO (&handle_rfds);
+ FD_ZERO (&handle_wfds);
+ FD_ZERO (&handle_xfds);
+
+ /* Classify handles. Create fd sets for sockets, poll the others. */
+ for (i = 0; i < nfds; i++)
+ {
+ if ((anyfds_in[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1)))) == 0)
+ continue;
+
+ h = (HANDLE) _get_osfhandle (i);
+ if (!h)
+ {
+ errno = EBADF;
+ return -1;
+ }
+
+ if (IsSocketHandle (h))
+ {
+ int requested = FD_CLOSE;
+
+ /* See above; socket handles are mapped onto select, but we
+ need to map descriptors to handles. */
+ if (rbits.in[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1))))
+ {
+ requested |= FD_READ | FD_ACCEPT;
+ FD_SET ((SOCKET) h, rfds);
+ FD_SET ((SOCKET) h, &handle_rfds);
+ }
+ if (wbits.in[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1))))
+ {
+ requested |= FD_WRITE | FD_CONNECT;
+ FD_SET ((SOCKET) h, wfds);
+ FD_SET ((SOCKET) h, &handle_wfds);
+ }
+ if (xbits.in[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1))))
+ {
+ requested |= FD_OOB;
+ FD_SET ((SOCKET) h, xfds);
+ FD_SET ((SOCKET) h, &handle_xfds);
+ }
+
+ WSAEventSelect ((SOCKET) h, hEvent, requested);
+ nsock++;
+ }
+ else
+ {
+ handle_array[nhandles++] = h;
+
+ /* Poll now. If we get an event, do not wait below. */
+ if (wait_timeout != 0
+ && windows_poll_handle (h, i, &rbits, &wbits, &xbits))
+ wait_timeout = 0;
+ }
+ }
+
+ /* Place a sentinel at the end of the array. */
+ handle_array[nhandles] = NULL;
+
+ /* When will the waiting period expire? */
+ if (wait_timeout != INFINITE)
+ tend = clock () + wait_timeout;
+
+restart:
+ if (wait_timeout == 0 || nsock == 0)
+ rc = 0;
+ else
+ {
+ /* See if we need to wait in the loop below. If any select is ready,
+ do MsgWaitForMultipleObjects anyway to dispatch messages, but
+ no need to call select again. */
+ rc = select (0, &handle_rfds, &handle_wfds, &handle_xfds, &tv0);
+ if (rc == 0)
+ {
+ /* Restore the fd_sets for the other select we do below. */
+ memcpy (&handle_rfds, rfds, sizeof (fd_set));
+ memcpy (&handle_wfds, wfds, sizeof (fd_set));
+ memcpy (&handle_xfds, xfds, sizeof (fd_set));
+ }
+ else
+ wait_timeout = 0;
+ }
+
+ /* How much is left to wait? */
+ if (wait_timeout != INFINITE)
+ {
+ clock_t tnow = clock ();
+ if (tend >= tnow)
+ wait_timeout = tend - tnow;
+ else
+ wait_timeout = 0;
+ }
+
+ 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 we haven't done it yet, check the status of the sockets. */
+ if (rc == 0 && nsock > 0)
+ rc = select (0, &handle_rfds, &handle_wfds, &handle_xfds, &tv0);
+
+ if (nhandles > 1)
+ {
+ /* Count results that are not counted in the return value of select. */
+ nhandles = 1;
+ for (i = 0; i < nfds; i++)
+ {
+ if ((anyfds_in[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1)))) == 0)
+ continue;
+
+ h = (HANDLE) _get_osfhandle (i);
+ if (h == handle_array[nhandles])
+ {
+ /* Not a socket. */
+ nhandles++;
+ windows_poll_handle (h, i, &rbits, &wbits, &xbits);
+ if (rbits.out[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1)))
+ || wbits.out[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1)))
+ || xbits.out[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1))))
+ rc++;
+ }
+ }
+
+ if (rc == 0
+ && (wait_timeout == INFINITE
+ /* If NHANDLES > 1, but no bits are set, it means we've
+ been told incorrectly that some handle was signaled.
+ This happens with anonymous pipes, which always cause
+ MsgWaitForMultipleObjects to exit immediately, but no
+ data is found ready to be read by windows_poll_handle.
+ To avoid a total failure (whereby we return zero and
+ don't wait at all), let's poll in a more busy loop. */
+ || (wait_timeout != 0 && nhandles > 1)))
+ {
+ /* Sleep 1 millisecond to avoid busy wait and retry with the
+ original fd_sets. */
+ memcpy (&handle_rfds, rfds, sizeof (fd_set));
+ memcpy (&handle_wfds, wfds, sizeof (fd_set));
+ memcpy (&handle_xfds, xfds, sizeof (fd_set));
+ SleepEx (1, TRUE);
+ goto restart;
+ }
+ if (timeout && wait_timeout == 0 && rc == 0)
+ timeout->tv_sec = timeout->tv_usec = 0;
+ }
+
+ /* Now fill in the results. */
+ FD_ZERO (rfds);
+ FD_ZERO (wfds);
+ FD_ZERO (xfds);
+ nhandles = 1;
+ for (i = 0; i < nfds; i++)
+ {
+ if ((anyfds_in[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1)))) == 0)
+ continue;
+
+ h = (HANDLE) _get_osfhandle (i);
+ if (h != handle_array[nhandles])
+ {
+ /* Perform handle->descriptor mapping. */
+ WSAEventSelect ((SOCKET) h, NULL, 0);
+ if (FD_ISSET (h, &handle_rfds))
+ FD_SET (i, rfds);
+ if (FD_ISSET (h, &handle_wfds))
+ FD_SET (i, wfds);
+ if (FD_ISSET (h, &handle_xfds))
+ FD_SET (i, xfds);
+ }
+ else
+ {
+ /* Not a socket. */
+ nhandles++;
+ if (rbits.out[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1))))
+ FD_SET (i, rfds);
+ if (wbits.out[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1))))
+ FD_SET (i, wfds);
+ if (xbits.out[i / CHAR_BIT] & (1 << (i & (CHAR_BIT - 1))))
+ FD_SET (i, xfds);
+ }
+ }
+
+ return rc;
+}
+
+#else /* ! Native Windows. */
+
+#include <sys/select.h>
+#include <stddef.h> /* NULL */
+#include <errno.h>
+#include <unistd.h>
+
+#undef select
+
+int
+rpl_select (int nfds, fd_set *rfds, fd_set *wfds, fd_set *xfds,
+ struct timeval *timeout)
+{
+ int i;
+
+ /* FreeBSD 8.2 has a bug: it does not always detect invalid fds. */
+ if (nfds < 0 || nfds > FD_SETSIZE)
+ {
+ errno = EINVAL;
+ return -1;
+ }
+ for (i = 0; i < nfds; i++)
+ {
+ if (((rfds && FD_ISSET (i, rfds))
+ || (wfds && FD_ISSET (i, wfds))
+ || (xfds && FD_ISSET (i, xfds)))
+ && dup2 (i, i) != i)
+ return -1;
+ }
+
+ /* Interix 3.5 has a bug: it does not support nfds == 0. */
+ if (nfds == 0)
+ {
+ nfds = 1;
+ rfds = NULL;
+ wfds = NULL;
+ xfds = NULL;
+ }
+ return select (nfds, rfds, wfds, xfds, timeout);
+}
+
+#endif
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