| 1 | /* |
| 2 | * Copyright 2002-2003 Red Hat Inc., Durham, North Carolina. |
| 3 | * |
| 4 | * All Rights Reserved. |
| 5 | * |
| 6 | * Permission is hereby granted, free of charge, to any person obtaining |
| 7 | * a copy of this software and associated documentation files (the |
| 8 | * "Software"), to deal in the Software without restriction, including |
| 9 | * without limitation on the rights to use, copy, modify, merge, |
| 10 | * publish, distribute, sublicense, and/or sell copies of the Software, |
| 11 | * and to permit persons to whom the Software is furnished to do so, |
| 12 | * subject to the following conditions: |
| 13 | * |
| 14 | * The above copyright notice and this permission notice (including the |
| 15 | * next paragraph) shall be included in all copies or substantial |
| 16 | * portions of the Software. |
| 17 | * |
| 18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| 19 | * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| 20 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| 21 | * NON-INFRINGEMENT. IN NO EVENT SHALL RED HAT AND/OR THEIR SUPPLIERS |
| 22 | * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN |
| 23 | * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN |
| 24 | * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 25 | * SOFTWARE. |
| 26 | */ |
| 27 | |
| 28 | /* |
| 29 | * Authors: |
| 30 | * Rickard E. (Rik) Faith <faith@redhat.com> |
| 31 | * |
| 32 | */ |
| 33 | |
| 34 | /** \file |
| 35 | * |
| 36 | * Provides an interface for handling SIGIO signals for input devices. */ |
| 37 | |
| 38 | #ifdef HAVE_DMX_CONFIG_H |
| 39 | #include <dmx-config.h> |
| 40 | #endif |
| 41 | |
| 42 | #include "inputstr.h" |
| 43 | #include "dmxinputinit.h" |
| 44 | #include "dmxsigio.h" |
| 45 | #include "dmxevents.h" |
| 46 | #include <signal.h> |
| 47 | #include <unistd.h> |
| 48 | #include <fcntl.h> |
| 49 | |
| 50 | static int dmxFdCount = 0; |
| 51 | static Bool dmxInputEnabled = TRUE; |
| 52 | |
| 53 | /* Define equivalents for non-POSIX systems (e.g., SGI IRIX, Solaris) */ |
| 54 | #ifndef O_ASYNC |
| 55 | #ifdef FASYNC |
| 56 | #define O_ASYNC FASYNC |
| 57 | #else |
| 58 | #define O_ASYNC 0 |
| 59 | #endif |
| 60 | #endif |
| 61 | #ifndef O_NONBLOCK |
| 62 | #define O_NONBLOCK FNONBLK |
| 63 | #endif |
| 64 | |
| 65 | static void |
| 66 | dmxSigioHandler(int sig) |
| 67 | { |
| 68 | int i, j; |
| 69 | DMXInputInfo *dmxInput; |
| 70 | |
| 71 | for (i = 0, dmxInput = &dmxInputs[0]; i < dmxNumInputs; i++, dmxInput++) { |
| 72 | if (dmxInput->sigioState == DMX_ACTIVESIGIO) { |
| 73 | for (j = 0; j < dmxInput->numDevs; j++) { |
| 74 | DMXLocalInputInfoPtr dmxLocal = dmxInput->devs[j]; |
| 75 | |
| 76 | if (dmxLocal->collect_events) { |
| 77 | dmxLocal->collect_events(&dmxLocal->pDevice->public, |
| 78 | dmxMotion, |
| 79 | dmxEnqueue, |
| 80 | dmxCheckSpecialKeys, DMX_NO_BLOCK); |
| 81 | } |
| 82 | } |
| 83 | } |
| 84 | } |
| 85 | } |
| 86 | |
| 87 | static void |
| 88 | dmxSigioHook(void) |
| 89 | { |
| 90 | struct sigaction a; |
| 91 | sigset_t s; |
| 92 | |
| 93 | memset(&a, 0, sizeof(a)); |
| 94 | a.sa_handler = dmxSigioHandler; |
| 95 | sigemptyset(&a.sa_mask); |
| 96 | sigaddset(&a.sa_mask, SIGIO); |
| 97 | sigaddset(&a.sa_mask, SIGALRM); |
| 98 | sigaddset(&a.sa_mask, SIGVTALRM); |
| 99 | sigaction(SIGIO, &a, 0); |
| 100 | |
| 101 | sigemptyset(&s); |
| 102 | sigprocmask(SIG_SETMASK, &s, 0); |
| 103 | } |
| 104 | |
| 105 | static void |
| 106 | dmxSigioUnhook(void) |
| 107 | { |
| 108 | struct sigaction a; |
| 109 | |
| 110 | memset(&a, 0, sizeof(a)); |
| 111 | a.sa_handler = SIG_IGN; |
| 112 | sigemptyset(&a.sa_mask); |
| 113 | sigaction(SIGIO, &a, 0); |
| 114 | } |
| 115 | |
| 116 | static void |
| 117 | dmxSigioAdd(DMXInputInfo * dmxInput) |
| 118 | { |
| 119 | int flags; |
| 120 | int i; |
| 121 | |
| 122 | switch (dmxInput->sigioState) { |
| 123 | case DMX_NOSIGIO: |
| 124 | return; |
| 125 | case DMX_USESIGIO: |
| 126 | dmxInput->sigioState = DMX_ACTIVESIGIO; |
| 127 | break; |
| 128 | case DMX_ACTIVESIGIO: |
| 129 | return; |
| 130 | } |
| 131 | |
| 132 | for (i = 0; i < dmxInput->sigioFdCount; i++) { |
| 133 | if (!dmxInput->sigioAdded[i]) { |
| 134 | int fd = dmxInput->sigioFd[i]; |
| 135 | |
| 136 | fcntl(fd, F_SETOWN, getpid()); |
| 137 | flags = fcntl(fd, F_GETFL); |
| 138 | flags |= O_ASYNC | O_NONBLOCK; |
| 139 | fcntl(fd, F_SETFL, flags); |
| 140 | |
| 141 | AddEnabledDevice(fd); |
| 142 | dmxInput->sigioAdded[i] = TRUE; |
| 143 | |
| 144 | if (++dmxFdCount == 1) |
| 145 | dmxSigioHook(); |
| 146 | } |
| 147 | } |
| 148 | } |
| 149 | |
| 150 | static void |
| 151 | dmxSigioRemove(DMXInputInfo * dmxInput) |
| 152 | { |
| 153 | int flags; |
| 154 | int i; |
| 155 | |
| 156 | switch (dmxInput->sigioState) { |
| 157 | case DMX_NOSIGIO: |
| 158 | return; |
| 159 | case DMX_USESIGIO: |
| 160 | return; |
| 161 | case DMX_ACTIVESIGIO: |
| 162 | dmxInput->sigioState = DMX_USESIGIO; |
| 163 | break; |
| 164 | } |
| 165 | |
| 166 | for (i = 0; i < dmxInput->sigioFdCount; i++) { |
| 167 | if (dmxInput->sigioAdded[i]) { |
| 168 | int fd = dmxInput->sigioFd[i]; |
| 169 | |
| 170 | dmxInput->sigioAdded[i] = FALSE; |
| 171 | RemoveEnabledDevice(fd); |
| 172 | |
| 173 | flags = fcntl(fd, F_GETFL); |
| 174 | flags &= ~(O_ASYNC | O_NONBLOCK); |
| 175 | fcntl(fd, F_SETFL, flags); |
| 176 | |
| 177 | if (!--dmxFdCount) |
| 178 | dmxSigioUnhook(); |
| 179 | } |
| 180 | } |
| 181 | } |
| 182 | |
| 183 | /** Enable SIGIO handling. This instantiates the handler with the OS. */ |
| 184 | void |
| 185 | dmxSigioEnableInput(void) |
| 186 | { |
| 187 | int i; |
| 188 | DMXInputInfo *dmxInput; |
| 189 | |
| 190 | dmxInputEnabled = TRUE; |
| 191 | for (i = 0, dmxInput = &dmxInputs[0]; i < dmxNumInputs; i++, dmxInput++) |
| 192 | dmxSigioAdd(dmxInput); |
| 193 | } |
| 194 | |
| 195 | /** Disable SIGIO handling. This removes the hanlder from the OS. */ |
| 196 | void |
| 197 | dmxSigioDisableInput(void) |
| 198 | { |
| 199 | int i; |
| 200 | DMXInputInfo *dmxInput; |
| 201 | |
| 202 | dmxInputEnabled = FALSE; |
| 203 | for (i = 0, dmxInput = &dmxInputs[0]; i < dmxNumInputs; i++, dmxInput++) |
| 204 | dmxSigioRemove(dmxInput); |
| 205 | } |
| 206 | |
| 207 | /** Make a note that the input device described in \a dmxInput will be |
| 208 | * using the file descriptor \a fd for SIGIO signals. Calls |
| 209 | * AddEnabledDevice ifi SIGIO handling has been enabled with |
| 210 | * #dmxSigioEnableInput(). */ |
| 211 | void |
| 212 | dmxSigioRegister(DMXInputInfo * dmxInput, int fd) |
| 213 | { |
| 214 | dmxInput->sigioState = DMX_USESIGIO; |
| 215 | if (dmxInput->sigioFdCount >= DMX_MAX_SIGIO_FDS) |
| 216 | dmxLog(dmxFatal, "Too many SIGIO file descriptors (%d >= %d)\n", |
| 217 | dmxInput->sigioFdCount, DMX_MAX_SIGIO_FDS); |
| 218 | |
| 219 | dmxInput->sigioFd[dmxInput->sigioFdCount++] = fd; |
| 220 | if (dmxInputEnabled) |
| 221 | dmxSigioAdd(dmxInput); |
| 222 | } |
| 223 | |
| 224 | /** Remove the notes that \a dmxInput is using any file descriptors for |
| 225 | * SIGIO signals. Calls RemoveEnabledDevice. */ |
| 226 | void |
| 227 | dmxSigioUnregister(DMXInputInfo * dmxInput) |
| 228 | { |
| 229 | if (dmxInput->sigioState == DMX_NOSIGIO) |
| 230 | return; |
| 231 | dmxSigioRemove(dmxInput); |
| 232 | dmxInput->sigioState = DMX_NOSIGIO; |
| 233 | dmxInput->sigioFdCount = 0; |
| 234 | } |