drivers/char/drm/sigio.c

   1 /* sigio.c -- Support for SIGIO handler -*- linux-c -*-
   2  * Created: Thu Jun  3 15:39:18 1999 by faith@precisioninsight.com
   3  * Revised: Thu Jun  3 16:16:35 1999 by faith@precisioninsight.com
   4  *
   5  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
   6  * All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the next
  16  * paragraph) shall be included in all copies or substantial portions of the
  17  * Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  25  * DEALINGS IN THE SOFTWARE.
  26  *
  27  * $PI: xc/programs/Xserver/hw/xfree86/os-support/shared/sigio.c,v 1.2 1999/06/14 21:11:29 faith Exp $
  28  * $XFree86: xc/programs/Xserver/hw/xfree86/os-support/shared/sigio.c,v 1.2 1999/06/14 12:02:11 dawes Exp $
  29  *
  30  */
  31
  32
  33 #ifdef XFree86Server
  34 # include "X.h"
  35 # include "xf86.h"
  36 # include "xf86drm.h"
  37 # include "xf86_OSlib.h"
  38 # include "xf86drm.h"
  39 #else
  40 # include <unistd.h>
  41 # include <signal.h>
  42 # include <fcntl.h>
  43 #endif
  44
  45 /*
  46  * Linux libc5 defines FASYNC, but not O_ASYNC.  Don't know if it is
  47  * functional or not.
  48  */
  49 #if defined(FASYNC) && !defined(O_ASYNC)
  50 #  define O_ASYNC FASYNC
  51 #endif
  52
  53 int
  54 xf86InstallSIGIOHandler(int fd, void (*f)(int))
  55 {
  56     struct sigaction sa;
  57     struct sigaction osa;
  58
  59     sigemptyset(&sa.sa_mask);
  60     sigaddset(&sa.sa_mask, SIGIO);
  61     sa.sa_flags   = 0;
  62     sa.sa_handler = f;
  63     sigaction(SIGIO, &sa, &osa);
  64     fcntl(fd, F_SETOWN, getpid());
  65     fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_ASYNC);
  66     return 0;
  67 }
  68
  69 int
  70 xf86RemoveSIGIOHandler(int fd)
  71 {
  72     struct sigaction sa;
  73     struct sigaction osa;
  74
  75     sigemptyset(&sa.sa_mask);
  76     sigaddset(&sa.sa_mask, SIGIO);
  77     sa.sa_flags   = 0;
  78     sa.sa_handler = SIG_DFL;
  79     fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) & ~O_ASYNC);
  80     sigaction(SIGIO, &sa, &osa);
  81     return 0;
  82 }