lcdproc/server/drivers/joy.c

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <termios.h>
#include <fcntl.h>
#include <string.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/types.h>


#define __u32 unsigned int
#define __u8 unsigned char
#include <linux/joystick.h>


#include "../../shared/debug.h"
#include "../../shared/str.h"

#define NAME_LENGTH 128



#include "lcd.h"
#include "joy.h"



//////////////////////////////////////////////////////////////////////////
////////////////////// Base "class" to derive from ///////////////////////
//////////////////////////////////////////////////////////////////////////

lcd_logical_driver *joy;

int fd;

struct js_event js;

char axes = 2;
char buttons = 2;
int jsversion = 0x000800;
char jsname[NAME_LENGTH] = "Unknown";

int *axis;
int *button;


// Configured for a Gravis Gamepad  (2 axis, 4 button)
char *axismap = "EFGHIJKLMNOPQRST";
char *buttonmap = "BDACEFGHIJKLMNOP";


////////////////////////////////////////////////////////////
// init() should set up any device-specific stuff, and
// point all the function pointers.
int
joy_init (struct lcd_logical_driver *driver, char *args)
{
   char device[256];
   char *argv[64];
   int argc, i, j;

   joy = driver;


   strcpy (device, "/dev/js0");

   argc = get_args (argv, args, 64);

   for (i = 0; i < argc; i++) {
      //printf("Arg(%i): %s\n", i, argv[i]);
      if (0 == strcmp (argv[i], "-d") || 0 == strcmp (argv[i], "--device")) {
	 if (i + 1 > argc) {
	    fprintf (stderr, "joy_init: %s requires an argument\n", argv[i]);
	    return -1;
	 }
	 strcpy (device, argv[++i]);
      } else if (0 == strcmp (argv[i], "-a") || 0 == strcmp (argv[i], "--axes")) {
	 if (i + 1 > argc) {
	    fprintf (stderr, "joy_init: %s requires an argument\n", argv[i]);
	    return -1;
	 }
	 strncpy (axismap, argv[++i], 16);
      } else if (0 == strcmp (argv[i], "-b") || 0 == strcmp (argv[i], "--buttons")) {
	 if (i + 1 > argc) {
	    fprintf (stderr, "joy_init: %s requires an argument\n", argv[i]);
	    return -1;
	 }
	 strncpy (buttonmap, argv[++i], 16);
      } else if (0 == strcmp (argv[i], "-h") || 0 == strcmp (argv[i], "--help")) {
	 printf ("LCDproc Joystick input driver\n" "\t-d\t--device\tSelect the input device to use [/dev/js0]\n" "\t-a\t--axes\t\tModify the axis map [%s]\n" "\t-b\t--buttons\tModify the button map [%s]\n" "\t-h\t--help\t\tShow this help information\n", axismap, buttonmap);
	 return -1;
      } else {
	 printf ("Invalid parameter: %s\n", argv[i]);
      }

   }





   driver->getkey = joy_getkey;
   driver->close = joy_close;


   /*  FIXME:  This crashes!
      if(args)
      {
      if(strlen(args) > 0)
      strcpy(device, args);
      }
    */

   fd = open (device, O_RDONLY);
   fcntl (fd, F_SETFL, O_NONBLOCK);

   if (fd < 0)
      return -1;

   ioctl (fd, JSIOCGVERSION, &jsversion);
   ioctl (fd, JSIOCGAXES, &axes);
   ioctl (fd, JSIOCGBUTTONS, &buttons);
   ioctl (fd, JSIOCGNAME (NAME_LENGTH), jsname);

   debug ("Joystick (%s) has %d axes and %d buttons. Driver version is %d.%d.%d.\n", jsname, axes, buttons, jsversion >> 16, (jsversion >> 8) & 0xff, jsversion & 0xff);

   axis = calloc (axes, sizeof (int));
   button = calloc (buttons, sizeof (char));

   return fd;			// 200 is arbitrary.  (must be 1 or more)
}


void
joy_close ()
{
   if (joy->framebuf != NULL)
      free (joy->framebuf);
   close (fd);

   joy->framebuf = NULL;

   // Why do I have so much trouble getting memory freed without segfaults??
   //if(axis) free(axis);
   //if(button) free(button);

}


//////////////////////////////////////////////////////////////////////
// Tries to read a character from an input device...
//
// Return 0 for "nothing available".
//
char
joy_getkey ()
{
   int i;
   int err;

   err = read (fd, &js, sizeof (struct js_event));
   if (err <= 0)
      return 0;
   if (err != sizeof (struct js_event)) {
      fprintf (stderr, "\nerror reading joystick\n");
      return 0;
   }
//   if(js.type & JS_EVENT_INIT) return 0;

   switch (js.type & ~JS_EVENT_INIT) {
   case JS_EVENT_BUTTON:
      button[js.number] = js.value;
      break;
   case JS_EVENT_AXIS:
      axis[js.number] = js.value;
      break;
   }

   if (buttons) {
      //printf("Buttons: ");
      for (i = 0; i < buttons; i++)
	 //printf("%2d:%s ", i, button[i] ? "on " : "off");
	 if (button[i])
	    return buttonmap[i];
   }

   if (axes) {
      //printf("Axes: ");
      for (i = 0; i < axes; i++) {
	 //printf("%2d:%6d ", i, axis[i]);
	 // Eliminate noise...
	 if (axis[i] > 20000)
	    return axismap[(2 * i) + 1];
	 if (axis[i] < -20000)
	    return axismap[(2 * i)];
      }
   }

   return 0;
}