/* $XFree86: xc/programs/Xserver/hw/xfree86/os-support/shared/sigio.c,v 1.19 2005/01/24 21:27:10 tsi Exp $ */ /* sigio.c -- Support for SIGIO handler installation and removal * Created: Thu Jun 3 15:39:18 1999 by faith@precisioninsight.com * * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. * * Authors: Rickard E. (Rik) Faith */ /* * Copyright (c) 2002 by The XFree86 Project, Inc. * All rights reserved. * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject * to the following conditions: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions, and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer * in the documentation and/or other materials provided with the * distribution, and in the same place and form as other copyright, * license and disclaimer information. * * 3. The end-user documentation included with the redistribution, * if any, must include the following acknowledgment: "This product * includes software developed by The XFree86 Project, Inc * (http://www.xfree86.org/) and its contributors", in the same * place and form as other third-party acknowledgments. Alternately, * this acknowledgment may appear in the software itself, in the * same form and location as other such third-party acknowledgments. * * 4. Except as contained in this notice, the name of The XFree86 * Project, Inc shall not be used in advertising or otherwise to * promote the sale, use or other dealings in this Software without * prior written authorization from The XFree86 Project, Inc. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE XFREE86 PROJECT, INC OR ITS CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * This code is an expensive no-op if the platform doesn't actually generate * SIGIO's, so _do_ check... */ #ifdef XFree86Server # include "X.h" # include "xf86.h" # include "xf86Priv.h" # include "xf86_OSlib.h" # include "inputstr.h" #else # include # include # include # include # include # include # include # include # define SYSCALL(call) while(((call) == -1) && (errno == EINTR)) #endif /* * Linux libc5 defines FASYNC, but not O_ASYNC. Don't know if it is * functional or not. */ #if defined(FASYNC) && !defined(O_ASYNC) # define O_ASYNC FASYNC #endif #ifdef MAX_DEVICES /* MAX_DEVICES represents the maximimum number of input devices usable * at the same time plus one entry for DRM support. */ # define MAX_FUNCS (MAX_DEVICES + 1) #else # define MAX_FUNCS 16 #endif typedef struct _xf86SigIOFunc { void (*f) (int, void *); int fd; void *closure; } Xf86SigIOFunc; static Xf86SigIOFunc xf86SigIOFuncs[MAX_FUNCS]; static int xf86SigIOMax; static int xf86SigIOMaxFd; static fd_set xf86SigIOMask; /* * Turn O_ASYNC or FIOASYNC on or off. */ static int xf86ASYNC (int fd, int async) { int flags; #ifdef O_ASYNC flags = fcntl(fd, F_GETFL); if (async) flags |= O_ASYNC; else flags &= ~O_ASYNC; return fcntl(fd, F_SETFL, flags); #else if (async) flags = 1; else flags = 0; return ioctl(fd, FIOASYNC, &flags); #endif } /* * SIGIO gives no way of discovering which fd signalled, select * to discover */ static void xf86SIGIO (int sig) { int i; fd_set ready; struct timeval to; int r; ready = xf86SigIOMask; to.tv_sec = 0; to.tv_usec = 0; SYSCALL (r = select (xf86SigIOMaxFd, &ready, 0, 0, &to)); for (i = 0; r > 0 && i < xf86SigIOMax; i++) if (xf86SigIOFuncs[i].f && FD_ISSET (xf86SigIOFuncs[i].fd, &ready)) { (*xf86SigIOFuncs[i].f)(xf86SigIOFuncs[i].fd, xf86SigIOFuncs[i].closure); r--; } #ifdef XFree86Server if (r > 0) { xf86Msg(X_ERROR, "SIGIO %d descriptors not handled\n", r); } #endif } static int xf86IsPipe (int fd) { struct stat buf; if (fstat (fd, &buf) < 0) return 0; return S_ISFIFO(buf.st_mode); } int xf86InstallSIGIOHandler(int fd, void (*f)(int, void *), void *closure) { struct sigaction sa; struct sigaction osa; int i; int blocked; for (i = 0; i < MAX_FUNCS; i++) { if (!xf86SigIOFuncs[i].f) { if (xf86IsPipe (fd)) return 0; blocked = xf86BlockSIGIO(); if (xf86ASYNC(fd, 1) == -1) { #ifdef XFree86Server xf86Msg(X_WARNING, "fcntl(%d, O_ASYNC): %s\n", fd, strerror(errno)); #else fprintf(stderr,"fcntl(%d, O_ASYNC): %s\n", fd, strerror(errno)); #endif xf86UnblockSIGIO(blocked); return 0; } if (fcntl(fd, F_SETOWN, getpid()) == -1) { #ifdef XFree86Server xf86Msg(X_WARNING, "fcntl(%d, F_SETOWN): %s\n", fd, strerror(errno)); #else fprintf(stderr,"fcntl(%d, F_SETOWN): %s\n", fd, strerror(errno)); #endif xf86UnblockSIGIO(blocked); return 0; } sigemptyset(&sa.sa_mask); sigaddset(&sa.sa_mask, SIGIO); sa.sa_flags = 0; sa.sa_handler = xf86SIGIO; sigaction(SIGIO, &sa, &osa); xf86SigIOFuncs[i].fd = fd; xf86SigIOFuncs[i].closure = closure; xf86SigIOFuncs[i].f = f; if (i >= xf86SigIOMax) xf86SigIOMax = i+1; if (fd >= xf86SigIOMaxFd) xf86SigIOMaxFd = fd + 1; FD_SET (fd, &xf86SigIOMask); xf86UnblockSIGIO(blocked); return 1; } /* Allow overwriting of the closure and callback */ else if (xf86SigIOFuncs[i].fd == fd) { xf86SigIOFuncs[i].closure = closure; xf86SigIOFuncs[i].f = f; return 1; } } return 0; } int xf86RemoveSIGIOHandler(int fd) { struct sigaction sa; struct sigaction osa; int i; int max; int maxfd; int ret; max = 0; maxfd = -1; ret = 0; for (i = 0; i < MAX_FUNCS; i++) { if (xf86SigIOFuncs[i].f) { if (xf86SigIOFuncs[i].fd == fd) { xf86SigIOFuncs[i].f = 0; xf86SigIOFuncs[i].fd = 0; xf86SigIOFuncs[i].closure = 0; FD_CLR (fd, &xf86SigIOMask); ret = 1; } else { max = i + 1; if (xf86SigIOFuncs[i].fd >= maxfd) maxfd = xf86SigIOFuncs[i].fd + 1; } } } if (ret) { xf86ASYNC(fd, 0); xf86SigIOMax = max; xf86SigIOMaxFd = maxfd; if (!max) { sigemptyset(&sa.sa_mask); sigaddset(&sa.sa_mask, SIGIO); sa.sa_flags = 0; sa.sa_handler = SIG_DFL; sigaction(SIGIO, &sa, &osa); } } return ret; } int xf86BlockSIGIO (void) { sigset_t set, old; sigemptyset (&set); sigaddset (&set, SIGIO); sigprocmask (SIG_BLOCK, &set, &old); return sigismember (&old, SIGIO); } void xf86UnblockSIGIO (int wasset) { sigset_t set; if (!wasset) { sigemptyset (&set); sigaddset (&set, SIGIO); sigprocmask (SIG_UNBLOCK, &set, NULL); } } #ifdef XFree86Server void xf86AssertBlockedSIGIO (char *where) { sigset_t set, old; sigemptyset (&set); sigprocmask (SIG_BLOCK, &set, &old); if (!sigismember (&old, SIGIO)) xf86Msg (X_ERROR, "SIGIO not blocked at %s\n", where); } /* XXX This is a quick hack for the benefit of xf86SetSilkenMouse() */ Bool xf86SIGIOSupported (void) { return 1; } #endif