diff options
Diffstat (limited to 'compat/poll/poll.c')
| -rw-r--r-- | compat/poll/poll.c | 614 |
1 files changed, 614 insertions, 0 deletions
diff --git a/compat/poll/poll.c b/compat/poll/poll.c new file mode 100644 index 0000000000..31163f2ae7 --- /dev/null +++ b/compat/poll/poll.c @@ -0,0 +1,614 @@ +/* Emulation for poll(2) + Contributed by Paolo Bonzini. + + Copyright 2001-2003, 2006-2011 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 + +#if defined(WIN32) +# include <malloc.h> +#endif + +#include <sys/types.h> + +/* Specification. */ +#include <poll.h> + +#include <errno.h> +#include <limits.h> +#include <assert.h> + +#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__ +# define WIN32_NATIVE +# if defined (_MSC_VER) && !defined(_WIN32_WINNT) +# define _WIN32_WINNT 0x0502 +# endif +# include <winsock2.h> +# include <windows.h> +# include <io.h> +# include <stdio.h> +# include <conio.h> +#else +# include <sys/time.h> +# include <sys/socket.h> +# ifndef NO_SYS_SELECT_H +# include <sys/select.h> +# endif +# 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; + + /* some systems can't use recv() on non-socket, including HP NonStop */ + else if (/* (r == -1) && */ socket_errno == ENOTSOCK) + happened |= (POLLIN | POLLRDNORM) & sought; + + 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 (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 && nfd) + { + 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); + +restart: + 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, NULL, 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++; + } + + if (!rc && timeout == INFTIM) + { + SwitchToThread(); + goto restart; + } + + return rc; +#endif +} |