/*

* Support for the X11 XInput extension.

*

* Please see the file LICENSE.txt in the source's root directory.

*

* This file written by Ryan C. Gordon.

*/

#include "manymouse.h"

/* Try to use this on everything but Windows and Mac OS by default... */

#ifndef SUPPORT_XINPUT2

#if ( (defined(_WIN32) || defined(__CYGWIN__)) )

#define SUPPORT_XINPUT2 0

#elif ( (defined(__MACH__)) && (defined(__APPLE__)) )

#define SUPPORT_XINPUT2 0

#else

#define SUPPORT_XINPUT2 1

#endif

#endif

#if SUPPORT_XINPUT2

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <dlfcn.h>

#include <X11/extensions/XInput2.h>

/* 32 is good enough for now. */

#define MAX_MICE 32

#define MAX_AXIS 16

typedef struct

{

int device_id;

int connected;

int relative[MAX_AXIS];

int minval[MAX_AXIS];

int maxval[MAX_AXIS];

char name[64];

} MouseStruct;

static MouseStruct mice[MAX_MICE];

static unsigned int available_mice = 0;

static Display *display = NULL;

static int xi2_opcode = 0;

/* !!! FIXME: this is cut-and-paste between a few targets now. Move it to

* !!! FIXME: manymouse.c ...

*/

/*

* Just trying to avoid malloc() here...we statically allocate a buffer

* for events and treat it as a ring buffer.

*/

/* !!! FIXME: tweak this? */

#define MAX_EVENTS 1024

static ManyMouseEvent input_events[MAX_EVENTS];

static volatile int input_events_read = 0;

static volatile int input_events_write = 0;

static void queue_event(const ManyMouseEvent *event)

{

/* copy the event info. We'll process it in ManyMouse_PollEvent(). */

memcpy(&input_events[input_events_write], event, sizeof (ManyMouseEvent));

input_events_write = ((input_events_write + 1) % MAX_EVENTS);

/* Ring buffer full? Lose oldest event. */

if (input_events_write == input_events_read)

{

/* !!! FIXME: we need to not lose mouse buttons here. */

input_events_read = ((input_events_read + 1) % MAX_EVENTS);

} /* if */

} /* queue_event */

static int dequeue_event(ManyMouseEvent *event)

{

if (input_events_read != input_events_write) /* no events if equal. */

{

memcpy(event, &input_events[input_events_read], sizeof (*event));

input_events_read = ((input_events_read + 1) % MAX_EVENTS);

return 1;

} /* if */

return 0; /* no event. */

} /* dequeue_event */

/*

* You _probably_ have Xlib on your system if you're on a Unix box where you

* are planning to plug in multiple mice. That being said, we don't want

* to force a project to add Xlib to their builds, or force the end-user to

* have Xlib installed if they are otherwise running a console app that the

* evdev driver would handle.

*

* We load all Xlib symbols at runtime, and fail gracefully if they aren't

* available for some reason...ManyMouse might be able to use the evdev

* driver or at least return a zero.

*

* On Linux (and probably others), you'll need to add -ldl to your link line,

* but it's part of glibc, so this is pretty much going to be there.

*/

static void *libx11 = NULL;

static void *libxext = NULL;

static void *libxi = NULL;

typedef int (*XExtErrHandler)(Display *, _Xconst char *, _Xconst char *);

static XExtErrHandler (*pXSetExtensionErrorHandler)(XExtErrHandler h) = 0;

static Display* (*pXOpenDisplay)(_Xconst char*) = 0;

static int (*pXCloseDisplay)(Display*) = 0;

static int (*pXISelectEvents)(Display*,Window,XIEventMask*,int) = 0;

static Bool (*pXQueryExtension)(Display*,_Xconst char*,int*,int*,int*) = 0;

static Status (*pXIQueryVersion)(Display*,int*,int*) = 0;

static XIDeviceInfo* (*pXIQueryDevice)(Display*,int,int*) = 0;

static void (*pXIFreeDeviceInfo)(XIDeviceInfo*) = 0;

static Bool (*pXGetEventData)(Display*,XGenericEventCookie*) = 0;

static void (*pXFreeEventData)(Display*,XGenericEventCookie*) = 0;

static int (*pXNextEvent)(Display*,XEvent*) = 0;

static int (*pXPending)(Display*) = 0;

static int (*pXFlush)(Display*) = 0;

static int (*pXEventsQueued)(Display*,int) = 0;

static int symlookup(void *dll, void **addr, const char *sym)

{

*addr = dlsym(dll, sym);

if (*addr == NULL)

return 0;

return 1;

} /* symlookup */

static int find_api_symbols(void)

{

void *dll = NULL;

#define LOOKUP(x) { if (!symlookup(dll, (void **) &p##x, #x)) return 0; }

dll = libx11 = dlopen("libX11.so.6", RTLD_GLOBAL | RTLD_LAZY);

if (dll == NULL)

return 0;

LOOKUP(XOpenDisplay);

LOOKUP(XCloseDisplay);

LOOKUP(XGetEventData);

LOOKUP(XFreeEventData);

LOOKUP(XQueryExtension);

LOOKUP(XNextEvent);

LOOKUP(XPending);

LOOKUP(XFlush);

LOOKUP(XEventsQueued);

dll = libxext = dlopen("libXext.so.6", RTLD_GLOBAL | RTLD_LAZY);

if (dll == NULL)

return 0;

LOOKUP(XSetExtensionErrorHandler);

dll = libxi = dlopen("libXi.so.6", RTLD_GLOBAL | RTLD_LAZY);

if (dll == NULL)

return 0;

LOOKUP(XISelectEvents);

LOOKUP(XIQueryVersion);

LOOKUP(XIQueryDevice);

LOOKUP(XIFreeDeviceInfo);

#undef LOOKUP

return 1;

} /* find_api_symbols */

static void xinput2_cleanup(void)

{

if (display != NULL)

{

pXCloseDisplay(display);

display = NULL;

} /* if */

memset(mice, '\0', sizeof (mice));

available_mice = 0;

#define LIBCLOSE(lib) { if (lib != NULL) { dlclose(lib); lib = NULL; } }

LIBCLOSE(libxi);

LIBCLOSE(libxext);

LIBCLOSE(libx11);

#undef LIBCLOSE

memset(input_events, '\0', sizeof (input_events));

input_events_read = input_events_write = 0;

} /* xinput2_cleanup */

static int init_mouse(MouseStruct *mouse, const XIDeviceInfo *devinfo)

{

XIAnyClassInfo **classes = devinfo->classes;

int axis = 0;

int i = 0;

/*

* we only look at "slave" devices. "Master" pointers are the logical

* cursors, "slave" pointers are the hardware that back them.

* "Floating slaves" are hardware that don't back a cursor.

*/

if ((devinfo->use != XISlavePointer) && (devinfo->use != XIFloatingSlave))

return 0; /* not a device we care about. */

else if (strstr(devinfo->name, "XTEST pointer") != NULL)

return 0; /* skip this nonsense. It's for the XTEST extension. */

mouse->device_id = devinfo->deviceid;

mouse->connected = 1;

for (i = 0; i < devinfo->num_classes; i++)

{

if ((classes[i]->type == XIValuatorClass) && (axis < MAX_AXIS))

{

const XIValuatorClassInfo *v = (XIValuatorClassInfo*) classes[i];

mouse->relative[axis] = (v->mode == XIModeRelative);

mouse->minval[axis] = (int) v->min;

mouse->maxval[axis] = (int) v->max;

axis++;

} /* if */

} /* for */

strncpy(mouse->name, devinfo->name, sizeof (mouse->name));

mouse->name[sizeof (mouse->name) - 1] = '\0';

return 1;

} /* init_mouse */

static int (*Xext_handler)(Display *, _Xconst char *, _Xconst char *) = NULL;

static int xext_errhandler(Display *d, _Xconst char *ext, _Xconst char *reason)

{

/* prevent Xlib spew to stderr for missing extensions. */

return (strcmp(reason, "missing") == 0) ? 0 : Xext_handler(d, ext, reason);

} /* xext_errhandler */

static int register_for_events(Display *dpy)

{

XIEventMask evmask;

unsigned char mask[3] = { 0, 0, 0 };

XISetMask(mask, XI_HierarchyChanged);

XISetMask(mask, XI_RawMotion);

XISetMask(mask, XI_RawButtonPress);

XISetMask(mask, XI_RawButtonRelease);

evmask.deviceid = XIAllDevices;

evmask.mask_len = sizeof (mask);

evmask.mask = mask;

/* !!! FIXME: retval? */

pXISelectEvents(dpy, DefaultRootWindow(dpy), &evmask, 1);

return 1;

} /* register_for_events */

static int x11_xinput2_init_internal(void)

{

const char *ext = "XInputExtension";

XIDeviceInfo *device_list = NULL;

int device_count = 0;

int available = 0;

int event = 0;

int error = 0;

int major = 2;

int minor = 0;

int i = 0;

xinput2_cleanup(); /* just in case... */

if (getenv("MANYMOUSE_NO_XINPUT2") != NULL)

return -1;

if (!find_api_symbols())

return -1; /* couldn't find all needed symbols. */

display = pXOpenDisplay(NULL);

if (display == NULL)

return -1; /* no X server at all */

Xext_handler = pXSetExtensionErrorHandler(xext_errhandler);

available = (pXQueryExtension(display, ext, &xi2_opcode, &event, &error) &&

(pXIQueryVersion(display, &major, &minor) != BadRequest));

pXSetExtensionErrorHandler(Xext_handler);

Xext_handler = NULL;

if (!available)

return -1; /* no XInput2 support. */

/*

* Register for events first, to prevent a race where we unplug a

* device between when we queried for the list and when we start

* listening for changes.

*/

if (!register_for_events(display))

return -1;

device_list = pXIQueryDevice(display, XIAllDevices, &device_count);

for (i = 0; i < device_count; i++)

{

MouseStruct *mouse = &mice[available_mice];

if (init_mouse(mouse, &device_list[i]))

available_mice++;

} /* for */

pXIFreeDeviceInfo(device_list);

return available_mice;

} /* x11_xinput2_init_internal */

static int x11_xinput2_init(void)

{

int retval = x11_xinput2_init_internal();

if (retval < 0)

xinput2_cleanup();

return retval;

} /* x11_xinput2_init */

static void x11_xinput2_quit(void)

{

xinput2_cleanup();

} /* x11_xinput2_quit */

static const char *x11_xinput2_name(unsigned int index)

{

return (index < available_mice) ? mice[index].name : NULL;

} /* x11_xinput2_name */

static int find_mouse_by_devid(const int devid)

{

int i;

const MouseStruct *mouse = mice;

for (i = 0; i < available_mice; i++, mouse++)

{

if (mouse->device_id == devid)

return (mouse->connected) ? i : -1;

} /* for */

return -1;

} /* find_mouse_by_devid */

static int get_next_x11_event(XEvent *xev)

{

int available = 0;

pXFlush(display);

if (pXEventsQueued(display, QueuedAlready))

available = 1;

else

{

/* XPending() blocks if there's no data, so select() first. */

struct timeval nowait;

const int fd = ConnectionNumber(display);

fd_set fdset;

FD_ZERO(&fdset);

FD_SET(fd, &fdset);

memset(&nowait, '\0', sizeof (nowait));

if (select(fd+1, &fdset, NULL, NULL, &nowait) == 1)

available = pXPending(display);

} /* else */

if (available)

{

memset(xev, '\0', sizeof (*xev));

pXNextEvent(display, xev);

return 1;

} /* if */

return 0;

} /* get_next_x11_event */

static void pump_events(void)

{

ManyMouseEvent event;

const int opcode = xi2_opcode;

const XIRawEvent *rawev = NULL;

const XIHierarchyEvent *hierev = NULL;

int mouse = 0;

XEvent xev;

int i = 0;

while (get_next_x11_event(&xev))

{

/* All XI2 events are "cookie" events...which need extra tapdance. */

if (xev.xcookie.type != GenericEvent)

continue;

else if (xev.xcookie.extension != opcode)

continue;

else if (!pXGetEventData(display, &xev.xcookie))

continue;

switch (xev.xcookie.evtype)

{

case XI_RawMotion:

rawev = (const XIRawEvent *) xev.xcookie.data;

mouse = find_mouse_by_devid(rawev->deviceid);

if (mouse != -1)

{

const double *values = rawev->raw_values;

int top = rawev->valuators.mask_len * 8;

if (top > MAX_AXIS)

top = MAX_AXIS;

for (i = 0; i < top; i++)

{

if (XIMaskIsSet(rawev->valuators.mask, i))

{

const int value = (int) *values;

if (mice[mouse].relative[i])

event.type = MANYMOUSE_EVENT_RELMOTION;

else

event.type = MANYMOUSE_EVENT_ABSMOTION;

event.device = mouse;

event.item = i;

event.value = value;

event.minval = mice[mouse].minval[i];

event.maxval = mice[mouse].maxval[i];

if ((!mice[mouse].relative[i]) || (value))

queue_event(&event);

values++;

} /* if */

} /* for */

} /* if */

break;

case XI_RawButtonPress:

case XI_RawButtonRelease:

rawev = (const XIRawEvent *) xev.xcookie.data;

mouse = find_mouse_by_devid(rawev->deviceid);

if (mouse != -1)

{

const int button = rawev->detail;

const int pressed = (xev.xcookie.evtype==XI_RawButtonPress);

/* gah, XInput2 still maps the wheel to buttons. */

if ((button >= 4) && (button <= 7))

{

if (pressed) /* ignore "up" for these "buttons" */

{

event.type = MANYMOUSE_EVENT_SCROLL;

event.device = mouse;

if ((button == 4) || (button == 5))

event.item = 0;

else

event.item = 1;

if ((button == 4) || (button == 6))

event.value = 1;

else

event.value = -1;

queue_event(&event);

} /* if */

} /* if */

else

{

event.type = MANYMOUSE_EVENT_BUTTON;

event.device = mouse;

event.item = button-1;

event.value = pressed;

queue_event(&event);

} /* else */

} /* if */

break;

case XI_HierarchyChanged:

hierev = (const XIHierarchyEvent *) xev.xcookie.data;

for (i = 0; i < hierev->num_info; i++)

{

if (hierev->info[i].flags & XISlaveRemoved)

{

mouse = find_mouse_by_devid(hierev->info[i].deviceid);

if (mouse != -1)

{

mice[mouse].connected = 0;

event.type = MANYMOUSE_EVENT_DISCONNECT;

event.device = mouse;

queue_event(&event);

} /* if */

} /* if */

} /* for */

break;

} /* switch */

pXFreeEventData(display, &xev.xcookie);

} /* while */

} /* pump_events */

static int x11_xinput2_poll(ManyMouseEvent *event)

{

if (dequeue_event(event)) /* ...favor existing events in the queue... */

return 1;

pump_events(); /* pump runloop for new hardware events... */

return dequeue_event(event); /* see if anything had shown up... */

} /* x11_xinput2_poll */

static const ManyMouseDriver ManyMouseDriver_interface =

{

"X11 XInput2 extension",

x11_xinput2_init,

x11_xinput2_quit,

x11_xinput2_name,

x11_xinput2_poll

};

const ManyMouseDriver *ManyMouseDriver_xinput2 = &ManyMouseDriver_interface;

#else

const ManyMouseDriver *ManyMouseDriver_xinput2 = 0;

#endif /* SUPPORT_XINPUT2 blocker */

/* end of x11_xinput2.c ... */