gb.joystick: Remove the concept of sticks

[GB.JOYSTICK]
* BUG: Joystick.{Stick,Direction} are not well-defined. Stick to axes as the Linux API does.

main/configure.ac

@@ -94,6 +94,15 @@ GB_COMPONENT(
   [GB_FIND(, /usr/local /usr, lib)],
   [$GB_INOTIFY_LIB])
 
+dnl ---- Check for the Linux joystick headers
+dnl TODO: Should also check if JS_VERSION >= 0x010000
+
+GB_COMPONENT(
+  joystick, JOYSTICK, gb.joystick, [joystick],
+  [GB_FIND(linux/joystick.h, /usr/local/lib /usr/local /usr/lib /usr, include)],
+  [GB_FIND(, /usr/local /usr, lib)],
+  [$C_LIB])
+
 dnl ---- We do not use libtool to load shared libraries anymore!
 
 AC_DEFINE(DONT_USE_LTDL, 1, [Do not use libtool to load shared libraries])
@@ -140,6 +149,7 @@ lib/data/Makefile \
 lib/clipper/Makefile \
 lib/inotify/Makefile \
 lib/jit/Makefile \
+lib/joystick/Makefile \
 ])
 AC_OUTPUT
 

main/lib/Makefile.am

@@ -1,2 +1,2 @@
-SUBDIRS = debug eval db compress vb option geom draw image gui gui.opengl gui.qt gui.qt.webkit gui.qt.opengl image.effect signal term complex data clipper gui.trayicon @INOTIFY_DIR@ jit
+SUBDIRS = debug eval db compress vb option geom draw image gui gui.opengl gui.qt gui.qt.webkit gui.qt.opengl image.effect signal term complex data clipper gui.trayicon @INOTIFY_DIR@ jit joystick
 EXTRA_DIST = gb.component

main/lib/joystick/Makefile.am

@@ -0,0 +1,10 @@
+COMPONENT = gb.joystick
+include $(top_srcdir)/component.am
+gblib_LTLIBRARIES = gb.joystick.la
+gb_joystick_la_LIBADD = @JOYSTICK_LIB@
+gb_joystick_la_LDFLAGS = -module @LD_FLAGS@ @JOYSTICK_LDFLAGS@
+gb_joystick_la_CPPFLAGS = @JOYSTICK_INC@ -I$(top_srcdir)/share
+
+gb_joystick_la_SOURCES = \
+  main.c main.h \
+  c_joystick.c c_joystick.h

main/lib/joystick/c_joystick.c

@@ -0,0 +1,278 @@
+/***************************************************************************
+
+  c_joystick.c
+
+  (C) 2015-2019 Tobias Boege <tobias@gambas-buch.de>
+  with bits from Cedron Dawg
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 1, or (at your option)
+  any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+  MA 02110-1301, USA.
+
+***************************************************************************/
+
+#define __C_JOYSTICK_C
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+
+#include <linux/joystick.h>
+
+#include "c_joystick.h"
+
+#define GB_ErrorErrno()	GB.Error(strerror(errno))
+
+typedef struct {
+	GB_BASE ob;
+	int fd;
+	struct js_event e;
+	int e_init; /* last event had JS_EVENT_INIT bit set? */
+} CJOYSTICK;
+
+DECLARE_EVENT(EVENT_Axis);
+DECLARE_EVENT(EVENT_Button);
+
+static void read_cb(int fd, int flags, CJOYSTICK *joy)
+{
+again:
+	if (read(fd, &joy->e, sizeof(joy->e)) != sizeof(joy->e)) {
+		if (errno == EINTR)
+			goto again;
+		GB_ErrorErrno();
+		return;
+	}
+
+	joy->e_init = !!(joy->e.type & JS_EVENT_INIT);
+
+	switch (joy->e.type & ~JS_EVENT_INIT) {
+	case JS_EVENT_AXIS:
+		GB.Raise(joy, EVENT_Axis, 0);
+		break;
+	case JS_EVENT_BUTTON:
+		GB.Raise(joy, EVENT_Button, 0);
+		break;
+	default:
+		fprintf(stderr, "[gb.joystick] Unknown event type '%d'. "
+		                "Please report this as a bug.\n", joy->e.type);
+		break;
+	}
+}
+
+#define THIS	((CJOYSTICK *) _object)
+
+/**G
+ * Create a new joystick object. The ~Path~ should point to the special
+ * character device for the joystick, usually something like
+ * `/dev/input/js0`.
+ **/
+BEGIN_METHOD(Joystick_new, GB_STRING path)
+
+	/* Need a NUL-terminated string */
+	char *path = GB.TempString(STRING(path), LENGTH(path));
+	int fd;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1) {
+		GB_ErrorErrno();
+		return;
+	}
+	THIS->fd = fd;
+	GB.Watch(fd, GB_WATCH_READ, (void *) read_cb, (intptr_t) THIS);
+
+END_METHOD
+
+BEGIN_METHOD_VOID(Joystick_free)
+
+	GB.Watch(THIS->fd, GB_WATCH_NONE, NULL, 0);
+	close(THIS->fd);
+
+END_METHOD
+
+/**G
+ * Return the number of axes of the joystick.
+ **/
+BEGIN_PROPERTY(Joystick_Axes)
+
+	unsigned char axes;
+
+	if (ioctl(THIS->fd, JSIOCGAXES, &axes) == -1) {
+		GB_ErrorErrno();
+		return;
+	}
+	GB.ReturnInteger(axes);
+
+END_PROPERTY
+
+/**G
+ * Return the number of buttons of the joystick.
+ **/
+BEGIN_PROPERTY(Joystick_Buttons)
+
+	unsigned char buttons;
+
+	if (ioctl(THIS->fd, JSIOCGBUTTONS, &buttons) == -1) {
+		GB_ErrorErrno();
+		return;
+	}
+	GB.ReturnInteger(buttons);
+
+END_PROPERTY
+
+/**G
+ * Return the device ID of the joystick.
+ **/
+BEGIN_PROPERTY(Joystick_Name)
+
+	char name[128];
+
+	memset(name, 0, sizeof(name));
+	if (ioctl(THIS->fd, JSIOCGNAME(128), name) == -1) {
+		GB_ErrorErrno();
+		return;
+	}
+	GB.ReturnNewZeroString(name);
+
+END_PROPERTY
+
+/**G
+ * When a joystick is opened, it issues a series of synthetic events
+ * for you to determine the initial state of axes and buttons.
+ *
+ * This property indicates if the latest event was such an initialisation
+ * event.
+ **/
+BEGIN_PROPERTY(Joystick_Init)
+
+	GB.ReturnBoolean(THIS->e_init);
+
+END_PROPERTY
+
+/**G
+ * Returns the index of the button that caused the most recent
+ * [Button](../.button) event.
+ **/
+BEGIN_PROPERTY(Joystick_Button)
+
+	GB.ReturnInteger(THIS->e.number);
+
+END_PROPERTY
+
+/**G
+ * Returns the index of the axis that caused the most recent
+ * [Axis](../.axis) event.
+ **/
+BEGIN_PROPERTY(Joystick_Axis)
+
+	GB.ReturnInteger(THIS->e.number);
+
+END_PROPERTY
+
+/**G
+ * In a Button event, this value is 0 or 1, according to whether the
+ * [button](../button) was pressed or released.
+ *
+ * In an Axis event, the value gives the position of the [axis](../axis)
+ * on a scale of -32767 to +32767, the range of a [Short](/lang/type/short).
+ *
+ * [[ warning
+ * The actual range of values seen in this property might be smaller
+ * than the full Short range **if the joystick calibration is off**.
+ * There exist external tools to recalibrate it but you may want to
+ * use *thresholds* when determining the intensity of the stick tilt,
+ * to make your program more robust to uncalibrated devices.
+ * ]]
+ **/
+BEGIN_PROPERTY(Joystick_Value)
+
+	GB.ReturnInteger(THIS->e.value);
+
+END_PROPERTY
+
+/**G
+ * A timestamp for the event in milliseconds. You can use this to detect
+ * whether buttons were pressed or sticks were moved "almost" simultaneously,
+ * independently of how fast you process them in your program.
+ *
+ * [[ warning
+ * The timestamp comes out of the kernel as an unsigned 32-bit integer,
+ * but Gambas has only signed integers. As such, timestamps will overflow
+ * and change sign around every 25 days and reset to zero every 50 days.
+ * ]]
+ **/
+BEGIN_PROPERTY(Joystick_Time)
+
+	GB.ReturnInteger(THIS->e.time);
+
+END_PROPERTY
+
+/**G
+ * This class represents a joystick/gamepad handled by the legacy
+ * [Linux Joystick API]. Once created it raises its [Button](.button)
+ * and [Axis](.axis) events to indicate input from the device.
+ *
+ * An analog control stick on a gamepad usually has two axes: one
+ * is vertical the other horizontal. However, there exist sticks with
+ * only a single axis and the numbering of axes is not always
+ * consistent with respect to being horizontal or vertical.
+ * Usually, you will want to let the user configure which buttons
+ * and axes should cause which actions in your program.
+ *
+ * Some properties of this class describe the device itself, while
+ * others describe the latest event that occurred. You should use
+ * them during event handlers only.
+ *
+ * [Linux Joystick API]: https://www.kernel.org/doc/html/latest/input/joydev/joystick-api.html
+ **/
+GB_DESC CJoystick[] = {
+	GB_DECLARE("Joystick", sizeof(CJOYSTICK)),
+
+	GB_PROPERTY_READ("Axes", "i", Joystick_Axes),
+	GB_PROPERTY_READ("Buttons", "i", Joystick_Buttons),
+	GB_PROPERTY_READ("Name", "s", Joystick_Name),
+	//GB_PROPERTY_READ("DriverVersion", "i", Joystick_DriverVersion),
+	//GB_PROPERTY("Correction", ".Joystick.Correction", Joystick_Correction),
+	// There are a few more ioctls in my <linux/joystick.h>
+	// which I found no documentation for...
+
+	/**G
+	 * Raised when a joystick stick changes position.
+	 * The axis on which the stick changed in is stored in the
+	 * [Axis](../axis) property and the new position is the
+	 * [Value](../value) property.
+	 **/
+	GB_EVENT("Axis", NULL, NULL, &EVENT_Axis),
+	/**G
+	 * Raised when a joystick button was pressed or released.
+	 * The index of the button is stored in the [Button](../button)
+	 * property. Its new state can be found in the [Value](../value)
+	 * property.
+	 **/
+	GB_EVENT("Button", NULL, NULL, &EVENT_Button),
+
+	GB_METHOD("_new", NULL, Joystick_new, "(Path)s"),
+	GB_METHOD("_free", NULL, Joystick_free, NULL),
+
+	/* Event data */
+	GB_PROPERTY_READ("Init", "b", Joystick_Init),
+	GB_PROPERTY_READ("Axis", "i", Joystick_Axis),
+	GB_PROPERTY_READ("Button", "i", Joystick_Button),
+	GB_PROPERTY_READ("Value", "i", Joystick_Value),
+	GB_PROPERTY_READ("Time", "i", Joystick_Time),
+
+	GB_END_DECLARE
+};

main/lib/joystick/c_joystick.h

@@ -0,0 +1,35 @@
+/***************************************************************************
+
+  c_joystick.h
+
+  (C) 2015-2019 Tobias Boege <tobias@gambas-buch.de>
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 1, or (at your option)
+  any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+  MA 02110-1301, USA.
+
+***************************************************************************/
+
+#ifndef __C_JOYSTICK_H
+#define __C_JOYSTICK_H
+
+#include "gambas.h"
+
+extern GB_INTERFACE GB;
+
+#ifndef __C_JOYSTICK_C
+extern GB_DESC CJoystick[];
+#endif
+
+#endif /* __C_JOYSTICK_H */

main/lib/joystick/gb.joystick.component

@@ -0,0 +1,4 @@
+[Component]
+Name=Linux Joystick API component
+Author=Tobias Boege
+State=Experimental

main/lib/joystick/main.c

@@ -0,0 +1,46 @@
+/***************************************************************************
+
+  main.c
+
+  gb.joystick component
+
+  (C) 2015-2019 Tobias Boege <tobias@gambas-buch.de>
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 1, or (at your option)
+  any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+  MA 02110-1301, USA.
+
+***************************************************************************/
+
+#define __MAIN_C
+
+#include "c_joystick.h"
+#include "main.h"
+
+GB_INTERFACE GB EXPORT;
+
+GB_DESC *GB_CLASSES[] EXPORT = {
+	CJoystick,
+
+	NULL
+};
+
+int EXPORT GB_INIT()
+{
+	return 0;
+}
+
+void EXPORT GB_EXIT()
+{
+}

main/lib/joystick/main.h

@@ -0,0 +1,35 @@
+/***************************************************************************
+
+  main.h
+
+  gb.joystick component
+
+  (C) 2015-2019 Tobias Boege <tobias@gambas-buch.de>
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 1, or (at your option)
+  any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+  MA 02110-1301, USA.
+
+***************************************************************************/
+
+#ifndef __MAIN_H
+#define __MAIN_H
+
+#include "gambas.h"
+
+#ifndef __MAIN_C
+extern GB_INTERFACE GB;
+#endif
+
+#endif /* __MAIN_H */