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
  35 #ifndef JOY_AXIS_DELTA
  36 #define JOY_AXIS_DELTA 500
  37 #endif
  38
  39 #ifndef JS_DEV
  40 #define JS_DEV "/dev/input/js0"
  41 #endif
  42
  43 #include <linux/joystick.h>
  44
  45 int axis[256];
  46 int btns = 0;
  47
  48 int mp_input_joystick_init(char* dev) {
  49   int fd,l=0;
  50   int initialized = 0;
  51   struct js_event ev;
  52
  53   mp_tmsg(MSGT_INPUT,MSGL_V,"Opening joystick device %s\n",dev ? dev : JS_DEV);
  54
  55   fd = open( dev ? dev : JS_DEV , O_RDONLY | O_NONBLOCK );
  56   if(fd < 0) {
  57     mp_tmsg(MSGT_INPUT,MSGL_ERR,"Can't open joystick device %s: %s\n",dev ? dev : JS_DEV,strerror(errno));
  58     return -1;
  59   }
  60
  61   while(! initialized) {
  62     l = 0;
  63     while((unsigned int)l < sizeof(struct js_event)) {
  64       int r = read(fd,((char*)&ev)+l,sizeof(struct js_event)-l);
  65       if(r < 0) {
  66         if(errno == EINTR)
  67           continue;
  68         else if(errno == EAGAIN) {
  69           initialized = 1;
  70           break;
  71         }
  72         mp_tmsg(MSGT_INPUT,MSGL_ERR,"Error while reading joystick device: %s\n",strerror(errno));
  73         close(fd);
  74         return -1;
  75       }
  76       l += r;
  77     }
  78     if((unsigned int)l < sizeof(struct js_event)) {
  79       if(l > 0)
  80         mp_tmsg(MSGT_INPUT,MSGL_WARN,"Joystick: We lose %d bytes of data\n",l);
  81       break;
  82     }
  83     if(ev.type == JS_EVENT_BUTTON)
  84       btns |= (ev.value << ev.number);
  85     if(ev.type == JS_EVENT_AXIS)
  86       axis[ev.number] = ev.value;
  87   }
  88
  89   return fd;
  90 }
  91
  92 int mp_input_joystick_read(void *ctx, int fd) {
  93   struct js_event ev;
  94   int l=0;
  95
  96   while((unsigned int)l < sizeof(struct js_event)) {
  97     int r = read(fd,&ev+l,sizeof(struct js_event)-l);
  98     if(r <= 0) {
  99       if(errno == EINTR)
 100         continue;
 101       else if(errno == EAGAIN)
 102         return MP_INPUT_NOTHING;
 103       if( r < 0)
 104         mp_tmsg(MSGT_INPUT,MSGL_ERR,"Error while reading joystick device: %s\n",strerror(errno));
 105       else
 106         mp_tmsg(MSGT_INPUT,MSGL_ERR,"Error while reading joystick device: %s\n","EOF");
 107       return MP_INPUT_DEAD;
 108     }
 109     l += r;
 110   }
 111
 112   if((unsigned int)l < sizeof(struct js_event)) {
 113     if(l > 0)
 114       mp_tmsg(MSGT_INPUT,MSGL_WARN,"Joystick: We lose %d bytes of data\n",l);
 115     return MP_INPUT_NOTHING;
 116   }
 117
 118   if(ev.type & JS_EVENT_INIT) {
 119     mp_tmsg(MSGT_INPUT,MSGL_WARN,"Joystick: warning init event, we have lost sync with driver.\n");
 120     ev.type &= ~JS_EVENT_INIT;
 121     if(ev.type == JS_EVENT_BUTTON) {
 122       int s = (btns >> ev.number) & 1;
 123       if(s == ev.value) // State is the same : ignore
 124         return MP_INPUT_NOTHING;
 125     }
 126     if(ev.type == JS_EVENT_AXIS) {
 127       if( ( axis[ev.number] == 1 && ev.value > JOY_AXIS_DELTA) ||
 128           (axis[ev.number] == -1 && ev.value < -JOY_AXIS_DELTA) ||
 129           (axis[ev.number] == 0 && ev.value >= -JOY_AXIS_DELTA && ev.value <= JOY_AXIS_DELTA)
 130           ) // State is the same : ignore
 131         return MP_INPUT_NOTHING;
 132     }
 133   }
 134
 135   if(ev.type & JS_EVENT_BUTTON) {
 136     btns &= ~(1 << ev.number);
 137     btns |= (ev.value << ev.number);
 138     if(ev.value == 1)
 139       return (JOY_BTN0 + ev.number) | MP_KEY_DOWN;
 140     else
 141       return JOY_BTN0 + ev.number;
 142   } else if(ev.type & JS_EVENT_AXIS) {
 143     if(ev.value < -JOY_AXIS_DELTA && axis[ev.number] != -1) {
 144       axis[ev.number] = -1;
 145       return (JOY_AXIS0_MINUS+(2*ev.number)) | MP_KEY_DOWN;
 146     } else if(ev.value > JOY_AXIS_DELTA && axis[ev.number] != 1) {
 147       axis[ev.number] = 1;
 148       return (JOY_AXIS0_PLUS+(2*ev.number)) | MP_KEY_DOWN;
 149     } else if(ev.value <= JOY_AXIS_DELTA && ev.value >= -JOY_AXIS_DELTA && axis[ev.number] != 0) {
 150       int r = axis[ev.number] == 1 ? JOY_AXIS0_PLUS+(2*ev.number) : JOY_AXIS0_MINUS+(2*ev.number);
 151       axis[ev.number] = 0;
 152       return r;
 153     } else
 154       return MP_INPUT_NOTHING;
 155   } else {
 156     mp_tmsg(MSGT_INPUT,MSGL_WARN,"Joystick warning unknown event type %d\n",ev.type);
 157     return MP_INPUT_ERROR;
 158   }
 159
 160   return MP_INPUT_NOTHING;
 161 }