input/joystick.c

   1 /*
   2  * This file is part of MPlayer.
   3  *
   4  * MPlayer is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * MPlayer is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with MPlayer; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #include "config.h"
  20
  21 #include "joystick.h"
  22 #include "input.h"
  23
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <unistd.h>
  28 #include <sys/types.h>
  29 #include <sys/stat.h>
  30 #include <fcntl.h>
  31 #include <errno.h>
  32
  33 #include "mp_msg.h"
  34 #include "keycodes.h"
  35
  36 #ifndef JOY_AXIS_DELTA
  37 #define JOY_AXIS_DELTA 500
  38 #endif
  39
  40 #ifndef JS_DEV
  41 #define JS_DEV "/dev/input/js0"
  42 #endif
  43
  44 #include <linux/joystick.h>
  45
  46 int axis[256];
  47 int btns = 0;
  48
  49 int mp_input_joystick_init(char* dev) {
  50   int fd,l=0;
  51   int initialized = 0;
  52   struct js_event ev;
  53
  54   mp_tmsg(MSGT_INPUT,MSGL_V,"Opening joystick device %s\n",dev ? dev : JS_DEV);
  55
  56   fd = open( dev ? dev : JS_DEV , O_RDONLY | O_NONBLOCK );
  57   if(fd < 0) {
  58     mp_tmsg(MSGT_INPUT,MSGL_ERR,"Can't open joystick device %s: %s\n",dev ? dev : JS_DEV,strerror(errno));
  59     return -1;
  60   }
  61
  62   while(! initialized) {
  63     l = 0;
  64     while((unsigned int)l < sizeof(struct js_event)) {
  65       int r = read(fd,((char*)&ev)+l,sizeof(struct js_event)-l);
  66       if(r < 0) {
  67         if(errno == EINTR)
  68           continue;
  69         else if(errno == EAGAIN) {
  70           initialized = 1;
  71           break;
  72         }
  73         mp_tmsg(MSGT_INPUT,MSGL_ERR,"Error while reading joystick device: %s\n",strerror(errno));
  74         close(fd);
  75         return -1;
  76       }
  77       l += r;
  78     }
  79     if((unsigned int)l < sizeof(struct js_event)) {
  80       if(l > 0)
  81         mp_tmsg(MSGT_INPUT,MSGL_WARN,"Joystick: We lose %d bytes of data\n",l);
  82       break;
  83     }
  84     if(ev.type == JS_EVENT_BUTTON)
  85       btns |= (ev.value << ev.number);
  86     if(ev.type == JS_EVENT_AXIS)
  87       axis[ev.number] = ev.value;
  88   }
  89
  90   return fd;
  91 }
  92
  93 int mp_input_joystick_read(void *ctx, int fd) {
  94   struct js_event ev;
  95   int l=0;
  96
  97   while((unsigned int)l < sizeof(struct js_event)) {
  98     int r = read(fd,&ev+l,sizeof(struct js_event)-l);
  99     if(r <= 0) {
 100       if(errno == EINTR)
 101         continue;
 102       else if(errno == EAGAIN)
 103         return MP_INPUT_NOTHING;
 104       if( r < 0)
 105         mp_tmsg(MSGT_INPUT,MSGL_ERR,"Error while reading joystick device: %s\n",strerror(errno));
 106       else
 107         mp_tmsg(MSGT_INPUT,MSGL_ERR,"Error while reading joystick device: %s\n","EOF");
 108       return MP_INPUT_DEAD;
 109     }
 110     l += r;
 111   }
 112
 113   if((unsigned int)l < sizeof(struct js_event)) {
 114     if(l > 0)
 115       mp_tmsg(MSGT_INPUT,MSGL_WARN,"Joystick: We lose %d bytes of data\n",l);
 116     return MP_INPUT_NOTHING;
 117   }
 118
 119   if(ev.type & JS_EVENT_INIT) {
 120     mp_tmsg(MSGT_INPUT,MSGL_WARN,"Joystick: warning init event, we have lost sync with driver.\n");
 121     ev.type &= ~JS_EVENT_INIT;
 122     if(ev.type == JS_EVENT_BUTTON) {
 123       int s = (btns >> ev.number) & 1;
 124       if(s == ev.value) // State is the same : ignore
 125         return MP_INPUT_NOTHING;
 126     }
 127     if(ev.type == JS_EVENT_AXIS) {
 128       if( ( axis[ev.number] == 1 && ev.value > JOY_AXIS_DELTA) ||
 129           (axis[ev.number] == -1 && ev.value < -JOY_AXIS_DELTA) ||
 130           (axis[ev.number] == 0 && ev.value >= -JOY_AXIS_DELTA && ev.value <= JOY_AXIS_DELTA)
 131           ) // State is the same : ignore
 132         return MP_INPUT_NOTHING;
 133     }
 134   }
 135
 136   if(ev.type & JS_EVENT_BUTTON) {
 137     btns &= ~(1 << ev.number);
 138     btns |= (ev.value << ev.number);
 139     if(ev.value == 1)
 140       return (JOY_BTN0 + ev.number) | MP_KEY_DOWN;
 141     else
 142       return JOY_BTN0 + ev.number;
 143   } else if(ev.type & JS_EVENT_AXIS) {
 144     if(ev.value < -JOY_AXIS_DELTA && axis[ev.number] != -1) {
 145       axis[ev.number] = -1;
 146       return (JOY_AXIS0_MINUS+(2*ev.number)) | MP_KEY_DOWN;
 147     } else if(ev.value > JOY_AXIS_DELTA && axis[ev.number] != 1) {
 148       axis[ev.number] = 1;
 149       return (JOY_AXIS0_PLUS+(2*ev.number)) | MP_KEY_DOWN;
 150     } else if(ev.value <= JOY_AXIS_DELTA && ev.value >= -JOY_AXIS_DELTA && axis[ev.number] != 0) {
 151       int r = axis[ev.number] == 1 ? JOY_AXIS0_PLUS+(2*ev.number) : JOY_AXIS0_MINUS+(2*ev.number);
 152       axis[ev.number] = 0;
 153       return r;
 154     } else
 155       return MP_INPUT_NOTHING;
 156   } else {
 157     mp_tmsg(MSGT_INPUT,MSGL_WARN,"Joystick warning unknown event type %d\n",ev.type);
 158     return MP_INPUT_ERROR;
 159   }
 160
 161   return MP_INPUT_NOTHING;
 162 }