src/x11_joystick.c - third_party/glfw - Git at Google

 //========================================================================
 // GLFW - An OpenGL library
 // Platform:    X11
 // API version: 3.0
 // WWW:         http://www.glfw.org/
 //------------------------------------------------------------------------
 // Copyright (c) 2002-2006 Marcus Geelnard
 // Copyright (c) 2006-2010 Camilla Berglund <elmindreda@elmindreda.org>
 //
 // This software is provided 'as-is', without any express or implied
 // warranty. In no event will the authors be held liable for any damages
 // arising from the use of this software.
 //
 // Permission is granted to anyone to use this software for any purpose,
 // including commercial applications, and to alter it and redistribute it
 // freely, subject to the following restrictions:
 //
 // 1. The origin of this software must not be misrepresented; you must not
 //    claim that you wrote the original software. If you use this software
 //    in a product, an acknowledgment in the product documentation would
 //    be appreciated but is not required.
 //
 // 2. Altered source versions must be plainly marked as such, and must not
 //    be misrepresented as being the original software.
 //
 // 3. This notice may not be removed or altered from any source
 //    distribution.
 //
 //========================================================================

 #include "internal.h"

 #ifdef __linux__
 #include <linux/joystick.h>

 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <errno.h>
 #include <regex.h>
 #include <dirent.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #endif // __linux__


 //========================================================================
 // Attempt to open the specified joystick device
 //========================================================================

 static int openJoystickDevice(int joy, const char* path)
 {
 #ifdef __linux__
     char numAxes, numButtons;
     char name[256];
     int fd, version;

     fd = open(path, O_RDONLY | O_NONBLOCK);
     if (fd == -1)
         return GL_FALSE;

     _glfw.x11.joystick[joy].fd = fd;

     // Verify that the joystick driver version is at least 1.0
     ioctl(fd, JSIOCGVERSION, &version);
     if (version < 0x010000)
     {
         // It's an old 0.x interface (we don't support it)
         close(fd);
         return GL_FALSE;
     }

     if (ioctl(fd, JSIOCGNAME(sizeof(name)), name) < 0)
         strncpy(name, "Unknown", sizeof(name));

     _glfw.x11.joystick[joy].name = strdup(name);

     ioctl(fd, JSIOCGAXES, &numAxes);
     _glfw.x11.joystick[joy].numAxes = (int) numAxes;

     ioctl(fd, JSIOCGBUTTONS, &numButtons);
     _glfw.x11.joystick[joy].numButtons = (int) numButtons;

     _glfw.x11.joystick[joy].axis = (float*) malloc(sizeof(float) * numAxes);
     if (_glfw.x11.joystick[joy].axis == NULL)
     {
         close(fd);

         _glfwInputError(GLFW_OUT_OF_MEMORY, NULL);
         return GL_FALSE;
     }

     _glfw.x11.joystick[joy].button = (unsigned char*) malloc(numButtons);
     if (_glfw.x11.joystick[joy].button == NULL)
     {
         free(_glfw.x11.joystick[joy].axis);
         close(fd);

         _glfwInputError(GLFW_OUT_OF_MEMORY, NULL);
         return GL_FALSE;
     }

     _glfw.x11.joystick[joy].present = GL_TRUE;
 #endif // __linux__

     return GL_TRUE;
 }


 //========================================================================
 // Polls for and processes events for all present joysticks
 //========================================================================

 static void pollJoystickEvents(void)
 {
 #ifdef __linux__
     int i;
     ssize_t result;
     struct js_event e;

     for (i = 0;  i <= GLFW_JOYSTICK_LAST;  i++)
     {
         if (!_glfw.x11.joystick[i].present)
             continue;

         // Read all queued events (non-blocking)
         for (;;)
         {
             errno = 0;
             result = read(_glfw.x11.joystick[i].fd, &e, sizeof(e));

             if (errno == ENODEV)
                 _glfw.x11.joystick[i].present = GL_FALSE;

             if (result == -1)
                 break;

             // We don't care if it's an init event or not
             e.type &= ~JS_EVENT_INIT;

             switch (e.type)
             {
                 case JS_EVENT_AXIS:
                     _glfw.x11.joystick[i].axis[e.number] =
                         (float) e.value / 32767.0f;

                     // We need to change the sign for the Y axes, so that
                     // positive = up/forward, according to the GLFW spec.
                     if (e.number & 1)
                     {
                         _glfw.x11.joystick[i].axis[e.number] =
                             -_glfw.x11.joystick[i].axis[e.number];
                     }

                     break;

                 case JS_EVENT_BUTTON:
                     _glfw.x11.joystick[i].button[e.number] =
                         e.value ? GLFW_PRESS : GLFW_RELEASE;
                     break;

                 default:
                     break;
             }
         }
     }
 #endif // __linux__
 }


 //////////////////////////////////////////////////////////////////////////
 //////                       GLFW internal API                      //////
 //////////////////////////////////////////////////////////////////////////

 //========================================================================
 // Initialize joystick interface
 //========================================================================

 int _glfwInitJoysticks(void)
 {
 #ifdef __linux__
     int i, joy = 0;
     regex_t regex;
     DIR* dir;
     const char* dirs[] =
     {
         "/dev/input",
         "/dev"
     };

     if (regcomp(&regex, "^js[0-9]\\+$", 0) != 0)
     {
         _glfwInputError(GLFW_PLATFORM_ERROR, "X11: Failed to compile regex");
         return GL_FALSE;
     }

     for (i = 0;  i < sizeof(dirs) / sizeof(dirs[0]);  i++)
     {
         struct dirent* entry;

         dir = opendir(dirs[i]);
         if (!dir)
             continue;

         while ((entry = readdir(dir)))
         {
             char path[20];
             regmatch_t match;

             if (regexec(&regex, entry->d_name, 1, &match, 0) != 0)
                 continue;

             snprintf(path, sizeof(path), "%s/%s", dirs[i], entry->d_name);
             if (openJoystickDevice(joy, path))
                 joy++;
         }

         closedir(dir);
     }

     regfree(&regex);
 #endif // __linux__

     return GL_TRUE;
 }


 //========================================================================
 // Close all opened joystick handles
 //========================================================================

 void _glfwTerminateJoysticks(void)
 {
 #ifdef __linux__
     int i;

     for (i = 0;  i <= GLFW_JOYSTICK_LAST;  i++)
     {
         if (_glfw.x11.joystick[i].present)
         {
             close(_glfw.x11.joystick[i].fd);
             free(_glfw.x11.joystick[i].axis);
             free(_glfw.x11.joystick[i].button);
             free(_glfw.x11.joystick[i].name);

             _glfw.x11.joystick[i].present = GL_FALSE;
         }
     }
 #endif // __linux__
 }


 //////////////////////////////////////////////////////////////////////////
 //////                       GLFW platform API                      //////
 //////////////////////////////////////////////////////////////////////////

 int _glfwPlatformGetJoystickParam(int joy, int param)
 {
     pollJoystickEvents();

     if (!_glfw.x11.joystick[joy].present)
         return 0;

     switch (param)
     {
         case GLFW_PRESENT:
             return GL_TRUE;

         case GLFW_AXES:
             return _glfw.x11.joystick[joy].numAxes;

         case GLFW_BUTTONS:
             return _glfw.x11.joystick[joy].numButtons;

         default:
             _glfwInputError(GLFW_INVALID_ENUM, NULL);
     }

     return 0;
 }

 int _glfwPlatformGetJoystickAxes(int joy, float* axes, int numAxes)
 {
     int i;

     pollJoystickEvents();

     if (!_glfw.x11.joystick[joy].present)
         return 0;

     if (_glfw.x11.joystick[joy].numAxes < numAxes)
         numAxes = _glfw.x11.joystick[joy].numAxes;

     for (i = 0;  i < numAxes;  i++)
         axes[i] = _glfw.x11.joystick[joy].axis[i];

     return numAxes;
 }

 int _glfwPlatformGetJoystickButtons(int joy, unsigned char* buttons,
                                     int numButtons)
 {
     int i;

     pollJoystickEvents();

     if (!_glfw.x11.joystick[joy].present)
         return 0;

     if (_glfw.x11.joystick[joy].numButtons < numButtons)
         numButtons = _glfw.x11.joystick[joy].numButtons;

     for (i = 0;  i < numButtons;  i++)
         buttons[i] = _glfw.x11.joystick[joy].button[i];

     return numButtons;
 }

 const char* _glfwPlatformGetJoystickName(int joy)
 {
     if (!_glfw.x11.joystick[joy].present)
         return NULL;

     return _glfw.x11.joystick[joy].name;
 }
	//========================================================================
	// GLFW - An OpenGL library
	// Platform: X11
	// API version: 3.0
	// WWW: http://www.glfw.org/
	//------------------------------------------------------------------------
	// Copyright (c) 2002-2006 Marcus Geelnard
	// Copyright (c) 2006-2010 Camilla Berglund <elmindreda@elmindreda.org>
	//
	// This software is provided 'as-is', without any express or implied
	// warranty. In no event will the authors be held liable for any damages
	// arising from the use of this software.
	//
	// Permission is granted to anyone to use this software for any purpose,
	// including commercial applications, and to alter it and redistribute it
	// freely, subject to the following restrictions:
	//
	// 1. The origin of this software must not be misrepresented; you must not
	// claim that you wrote the original software. If you use this software
	// in a product, an acknowledgment in the product documentation would
	// be appreciated but is not required.
	//
	// 2. Altered source versions must be plainly marked as such, and must not
	// be misrepresented as being the original software.
	//
	// 3. This notice may not be removed or altered from any source
	// distribution.
	//
	//========================================================================

	#include "internal.h"

	#ifdef __linux__
	#include <linux/joystick.h>

	#include <sys/types.h>
	#include <sys/stat.h>
	#include <fcntl.h>
	#include <errno.h>
	#include <regex.h>
	#include <dirent.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#endif // __linux__


	//========================================================================
	// Attempt to open the specified joystick device
	//========================================================================

	static int openJoystickDevice(int joy, const char* path)
	{
	#ifdef __linux__
	char numAxes, numButtons;
	char name[256];
	int fd, version;

	fd = open(path, O_RDONLY \| O_NONBLOCK);
	if (fd == -1)
	return GL_FALSE;

	_glfw.x11.joystick[joy].fd = fd;

	// Verify that the joystick driver version is at least 1.0
	ioctl(fd, JSIOCGVERSION, &version);
	if (version < 0x010000)
	{
	// It's an old 0.x interface (we don't support it)
	close(fd);
	return GL_FALSE;
	}

	if (ioctl(fd, JSIOCGNAME(sizeof(name)), name) < 0)
	strncpy(name, "Unknown", sizeof(name));

	_glfw.x11.joystick[joy].name = strdup(name);

	ioctl(fd, JSIOCGAXES, &numAxes);
	_glfw.x11.joystick[joy].numAxes = (int) numAxes;

	ioctl(fd, JSIOCGBUTTONS, &numButtons);
	_glfw.x11.joystick[joy].numButtons = (int) numButtons;

	_glfw.x11.joystick[joy].axis = (float) malloc(sizeof(float) numAxes);
	if (_glfw.x11.joystick[joy].axis == NULL)
	{
	close(fd);

	_glfwInputError(GLFW_OUT_OF_MEMORY, NULL);
	return GL_FALSE;
	}

	_glfw.x11.joystick[joy].button = (unsigned char*) malloc(numButtons);
	if (_glfw.x11.joystick[joy].button == NULL)
	{
	free(_glfw.x11.joystick[joy].axis);
	close(fd);

	_glfwInputError(GLFW_OUT_OF_MEMORY, NULL);
	return GL_FALSE;
	}

	_glfw.x11.joystick[joy].present = GL_TRUE;
	#endif // __linux__

	return GL_TRUE;
	}


	//========================================================================
	// Polls for and processes events for all present joysticks
	//========================================================================

	static void pollJoystickEvents(void)
	{
	#ifdef __linux__
	int i;
	ssize_t result;
	struct js_event e;

	for (i = 0; i <= GLFW_JOYSTICK_LAST; i++)
	{
	if (!_glfw.x11.joystick[i].present)
	continue;

	// Read all queued events (non-blocking)
	for (;;)
	{
	errno = 0;
	result = read(_glfw.x11.joystick[i].fd, &e, sizeof(e));

	if (errno == ENODEV)
	_glfw.x11.joystick[i].present = GL_FALSE;

	if (result == -1)
	break;

	// We don't care if it's an init event or not
	e.type &= ~JS_EVENT_INIT;

	switch (e.type)
	{
	case JS_EVENT_AXIS:
	_glfw.x11.joystick[i].axis[e.number] =
	(float) e.value / 32767.0f;

	// We need to change the sign for the Y axes, so that
	// positive = up/forward, according to the GLFW spec.
	if (e.number & 1)
	{
	_glfw.x11.joystick[i].axis[e.number] =
	-_glfw.x11.joystick[i].axis[e.number];
	}

	break;

	case JS_EVENT_BUTTON:
	_glfw.x11.joystick[i].button[e.number] =
	e.value ? GLFW_PRESS : GLFW_RELEASE;
	break;

	default:
	break;
	}
	}
	}
	#endif // __linux__
	}


	//////////////////////////////////////////////////////////////////////////
	////// GLFW internal API //////
	//////////////////////////////////////////////////////////////////////////

	//========================================================================
	// Initialize joystick interface
	//========================================================================

	int _glfwInitJoysticks(void)
	{
	#ifdef __linux__
	int i, joy = 0;
	regex_t regex;
	DIR* dir;
	const char* dirs[] =
	{
	"/dev/input",
	"/dev"
	};

	if (regcomp(&regex, "^js[0-9]\\+$", 0) != 0)
	{
	_glfwInputError(GLFW_PLATFORM_ERROR, "X11: Failed to compile regex");
	return GL_FALSE;
	}

	for (i = 0; i < sizeof(dirs) / sizeof(dirs[0]); i++)
	{
	struct dirent* entry;

	dir = opendir(dirs[i]);
	if (!dir)
	continue;

	while ((entry = readdir(dir)))
	{
	char path[20];
	regmatch_t match;

	if (regexec(&regex, entry->d_name, 1, &match, 0) != 0)
	continue;

	snprintf(path, sizeof(path), "%s/%s", dirs[i], entry->d_name);
	if (openJoystickDevice(joy, path))
	joy++;
	}

	closedir(dir);
	}

	regfree(&regex);
	#endif // __linux__

	return GL_TRUE;
	}


	//========================================================================
	// Close all opened joystick handles
	//========================================================================

	void _glfwTerminateJoysticks(void)
	{
	#ifdef __linux__
	int i;

	for (i = 0; i <= GLFW_JOYSTICK_LAST; i++)
	{
	if (_glfw.x11.joystick[i].present)
	{
	close(_glfw.x11.joystick[i].fd);
	free(_glfw.x11.joystick[i].axis);
	free(_glfw.x11.joystick[i].button);
	free(_glfw.x11.joystick[i].name);

	_glfw.x11.joystick[i].present = GL_FALSE;
	}
	}
	#endif // __linux__
	}


	//////////////////////////////////////////////////////////////////////////
	////// GLFW platform API //////
	//////////////////////////////////////////////////////////////////////////

	int _glfwPlatformGetJoystickParam(int joy, int param)
	{
	pollJoystickEvents();

	if (!_glfw.x11.joystick[joy].present)
	return 0;

	switch (param)
	{
	case GLFW_PRESENT:
	return GL_TRUE;

	case GLFW_AXES:
	return _glfw.x11.joystick[joy].numAxes;

	case GLFW_BUTTONS:
	return _glfw.x11.joystick[joy].numButtons;

	default:
	_glfwInputError(GLFW_INVALID_ENUM, NULL);
	}

	return 0;
	}

	int _glfwPlatformGetJoystickAxes(int joy, float* axes, int numAxes)
	{
	int i;

	pollJoystickEvents();

	if (!_glfw.x11.joystick[joy].present)
	return 0;

	if (_glfw.x11.joystick[joy].numAxes < numAxes)
	numAxes = _glfw.x11.joystick[joy].numAxes;

	for (i = 0; i < numAxes; i++)
	axes[i] = _glfw.x11.joystick[joy].axis[i];

	return numAxes;
	}

	int _glfwPlatformGetJoystickButtons(int joy, unsigned char* buttons,
	int numButtons)
	{
	int i;

	pollJoystickEvents();

	if (!_glfw.x11.joystick[joy].present)
	return 0;

	if (_glfw.x11.joystick[joy].numButtons < numButtons)
	numButtons = _glfw.x11.joystick[joy].numButtons;

	for (i = 0; i < numButtons; i++)
	buttons[i] = _glfw.x11.joystick[joy].button[i];

	return numButtons;
	}

	const char* _glfwPlatformGetJoystickName(int joy)
	{
	if (!_glfw.x11.joystick[joy].present)
	return NULL;

	return _glfw.x11.joystick[joy].name;
	}