static bool
_nc_mouse_parse(SCREEN *sp, int runcount)
/* parse a run of atomic mouse events into a gesture */
{
MEVENT *eventp = sp->_mouse_eventp;
MEVENT *ep, *runp, *next, *prev = PREV(eventp);
int n;
int b;
bool merge;
TR(MY_TRACE, ("_nc_mouse_parse(%d) called", runcount));
/*
* When we enter this routine, the event list next-free pointer
* points just past a run of mouse events that we know were separated
* in time by less than the critical click interval. The job of this
* routine is to collapse this run into a single higher-level event
* or gesture.
*
* We accomplish this in two passes. The first pass merges press/release
* pairs into click events. The second merges runs of click events into
* double or triple-click events.
*
* It's possible that the run may not resolve to a single event (for
* example, if the user quadruple-clicks). If so, leading events
* in the run are ignored.
*
* Note that this routine is independent of the format of the specific
* format of the pointing-device's reports. We can use it to parse
* gestures on anything that reports press/release events on a per-
* button basis, as long as the device-dependent mouse code puts stuff
* on the queue in MEVENT format.
*/
if (runcount == 1) {
TR(MY_TRACE,
("_nc_mouse_parse: returning simple mouse event %s at slot %ld",
_nc_tracemouse(sp, prev),
(long) IndexEV(sp, prev)));
return (prev->id >= NORMAL_EVENT)
? ((prev->bstate & sp->_mouse_mask) ? TRUE : FALSE)
: FALSE;
}
/* find the start of the run */
runp = eventp;
for (n = runcount; n > 0; n--) {
runp = PREV(runp);
}
#ifdef TRACE
if (USE_TRACEF(TRACE_IEVENT)) {
_trace_slot(sp, "before mouse press/release merge:");
_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
RunParams(sp, eventp, runp),
runcount);
_nc_unlock_global(tracef);
}
#endif /* TRACE */
/* first pass; merge press/release pairs */
do {
merge = FALSE;
for (ep = runp; (next = NEXT(ep)) != eventp; ep = next) {
#define MASK_CHANGED(x) (!(ep->bstate & MASK_PRESS(x)) \
== !(next->bstate & MASK_RELEASE(x)))
if (ep->x == next->x && ep->y == next->y
&& (ep->bstate & BUTTON_PRESSED)
&& MASK_CHANGED(1)
&& MASK_CHANGED(2)
&& MASK_CHANGED(3)
&& MASK_CHANGED(4)
#if NCURSES_MOUSE_VERSION == 2
&& MASK_CHANGED(5)
#endif
) {
for (b = 1; b <= MAX_BUTTONS; ++b) {
if ((sp->_mouse_mask & MASK_CLICK(b))
&& (ep->bstate & MASK_PRESS(b))) {
ep->bstate &= ~MASK_PRESS(b);
ep->bstate |= MASK_CLICK(b);
merge = TRUE;
}
}
if (merge)
next->id = INVALID_EVENT;
}
}
} while
(merge);
#ifdef TRACE
if (USE_TRACEF(TRACE_IEVENT)) {
_trace_slot(sp, "before mouse click merge:");
_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
RunParams(sp, eventp, runp),
runcount);
_nc_unlock_global(tracef);
}
#endif /* TRACE */
/*
* Second pass; merge click runs. At this point, click events are
* each followed by one invalid event. We merge click events
* forward in the queue.
*
* NOTE: There is a problem with this design! If the application
* allows enough click events to pile up in the circular queue so
* they wrap around, it will cheerfully merge the newest forward
* into the oldest, creating a bogus doubleclick and confusing
* the queue-traversal logic rather badly. Generally this won't
* happen, because calling getmouse() marks old events invalid and
* ineligible for merges. The true solution to this problem would
* be to timestamp each MEVENT and perform the obvious sanity check,
* but the timer element would have to have sub-second resolution,
* which would get us into portability trouble.
*/
do {
MEVENT *follower;
merge = FALSE;
for (ep = runp; (next = NEXT(ep)) != eventp; ep = next)
if (ep->id != INVALID_EVENT) {
if (next->id != INVALID_EVENT)
continue;
follower = NEXT(next);
if (follower->id == INVALID_EVENT)
continue;
/* merge click events forward */
if ((ep->bstate & BUTTON_CLICKED)
&& (follower->bstate & BUTTON_CLICKED)) {
for (b = 1; b <= MAX_BUTTONS; ++b) {
if ((sp->_mouse_mask & MASK_DOUBLE_CLICK(b))
&& (follower->bstate & MASK_CLICK(b))) {
follower->bstate &= ~MASK_CLICK(b);
follower->bstate |= MASK_DOUBLE_CLICK(b);
merge = TRUE;
}
}
if (merge)
ep->id = INVALID_EVENT;
}
/* merge double-click events forward */
if ((ep->bstate & BUTTON_DOUBLE_CLICKED)
&& (follower->bstate & BUTTON_CLICKED)) {
for (b = 1; b <= MAX_BUTTONS; ++b) {
if ((sp->_mouse_mask & MASK_TRIPLE_CLICK(b))
&& (follower->bstate & MASK_CLICK(b))) {
follower->bstate &= ~MASK_CLICK(b);
follower->bstate |= MASK_TRIPLE_CLICK(b);
merge = TRUE;
}
}
if (merge)
ep->id = INVALID_EVENT;
}
}
} while
(merge);
#ifdef TRACE
if (USE_TRACEF(TRACE_IEVENT)) {
_trace_slot(sp, "before mouse event queue compaction:");
_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
RunParams(sp, eventp, runp),
runcount);
_nc_unlock_global(tracef);
}
#endif /* TRACE */
/*
* Now try to throw away trailing events flagged invalid, or that
* don't match the current event mask.
*/
for (; runcount; prev = PREV(eventp), runcount--)
if (prev->id == INVALID_EVENT || !(prev->bstate & sp->_mouse_mask)) {
sp->_mouse_eventp = eventp = prev;
}
#ifdef TRACE
if (USE_TRACEF(TRACE_IEVENT)) {
_trace_slot(sp, "after mouse event queue compaction:");
_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
RunParams(sp, eventp, runp),
runcount);
_nc_unlock_global(tracef);
}
for (ep = runp; ep != eventp; ep = NEXT(ep))
if (ep->id != INVALID_EVENT)
TR(MY_TRACE,
("_nc_mouse_parse: returning composite mouse event %s at slot %ld",
_nc_tracemouse(sp, ep),
(long) IndexEV(sp, ep)));
#endif /* TRACE */
/* after all this, do we have a valid event? */
return (PREV(eventp)->id != INVALID_EVENT);
}
static bool
_nc_mouse_parse(SCREEN *sp, int runcount)
/* parse a run of atomic mouse events into a gesture */
{
MEVENT *eventp = sp->_mouse_eventp;
MEVENT *next, *ep;
MEVENT *first_valid = NULL;
MEVENT *first_invalid = NULL;
int n;
int b;
bool merge;
bool endLoop;
TR(MY_TRACE, ("_nc_mouse_parse(%d) called", runcount));
/*
* When we enter this routine, the event list next-free pointer
* points just past a run of mouse events that we know were separated
* in time by less than the critical click interval. The job of this
* routine is to collapse this run into a single higher-level event
* or gesture.
*
* We accomplish this in two passes. The first pass merges press/release
* pairs into click events. The second merges runs of click events into
* double or triple-click events.
*
* It's possible that the run may not resolve to a single event (for
* example, if the user quadruple-clicks). If so, leading events
* in the run are ignored if user does not call getmouse in a loop (getting
* them from newest to older).
*
* Note that this routine is independent of the format of the specific
* format of the pointing-device's reports. We can use it to parse
* gestures on anything that reports press/release events on a per-
* button basis, as long as the device-dependent mouse code puts stuff
* on the queue in MEVENT format.
*/
/*
* Reset all events that were not set, in case the user sometimes calls
* getmouse only once and other times until there are no more events in
* queue.
*
* This also allows reaching the beginning of the run.
*/
ep = eventp;
for (n = runcount; n < EV_MAX; n++) {
Invalidate(ep);
ep = NEXT(ep);
}
#ifdef TRACE
if (USE_TRACEF(TRACE_IEVENT)) {
_trace_slot(sp, "before mouse press/release merge:");
_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
RunParams(sp, eventp, ep),
runcount);
_nc_unlock_global(tracef);
}
#endif /* TRACE */
/* first pass; merge press/release pairs */
endLoop = FALSE;
while (!endLoop) {
next = NEXT(ep);
if (next == eventp) {
/* Will end the loop, but compact before */
endLoop = TRUE;
} else {
#define MASK_CHANGED(x) (!(ep->bstate & MASK_PRESS(x)) \
== !(next->bstate & MASK_RELEASE(x)))
if (ValidEvent(ep) && ValidEvent(next)
&& ep->x == next->x && ep->y == next->y
&& (ep->bstate & BUTTON_PRESSED)
&& (!(next->bstate & BUTTON_PRESSED))) {
bool changed = TRUE;
for (b = 1; b <= MAX_BUTTONS; ++b) {
if (!MASK_CHANGED(b)) {
changed = FALSE;
break;
}
}
if (changed) {
merge = FALSE;
for (b = 1; b <= MAX_BUTTONS; ++b) {
if ((sp->_mouse_mask & MASK_CLICK(b))
&& (ep->bstate & MASK_PRESS(b))) {
next->bstate &= ~MASK_RELEASE(b);
next->bstate |= MASK_CLICK(b);
merge = TRUE;
}
}
if (merge) {
Invalidate(ep);
}
}
}
}
/* Compact valid events */
if (!ValidEvent(ep)) {
if ((first_valid != NULL) && (first_invalid == NULL)) {
first_invalid = ep;
}
} else {
if (first_valid == NULL) {
first_valid = ep;
} else if (first_invalid != NULL) {
*first_invalid = *ep;
Invalidate(ep);
first_invalid = NEXT(first_invalid);
}
}
ep = next;
}
if (first_invalid != NULL) {
eventp = first_invalid;
}
#ifdef TRACE
if (USE_TRACEF(TRACE_IEVENT)) {
_trace_slot(sp, "before mouse click merge:");
if (first_valid == NULL) {
_tracef("_nc_mouse_parse: no valid event");
} else {
_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
RunParams(sp, eventp, first_valid),
runcount);
_nc_unlock_global(tracef);
}
}
#endif /* TRACE */
/*
* Second pass; merge click runs. We merge click events forward in the
* queue. For example, double click can be changed to triple click.
*
* NOTE: There is a problem with this design! If the application
* allows enough click events to pile up in the circular queue so
* they wrap around, it will cheerfully merge the newest forward
* into the oldest, creating a bogus doubleclick and confusing
* the queue-traversal logic rather badly. Generally this won't
* happen, because calling getmouse() marks old events invalid and
* ineligible for merges. The true solution to this problem would
* be to timestamp each MEVENT and perform the obvious sanity check,
* but the timer element would have to have sub-second resolution,
* which would get us into portability trouble.
*/
first_invalid = NULL;
endLoop = (first_valid == NULL);
ep = first_valid;
while (!endLoop) {
next = NEXT(ep);
if (next == eventp) {
/* Will end the loop, but check event type and compact before */
endLoop = TRUE;
} else if (!ValidEvent(next)) {
continue;
} else {
/* merge click events forward */
if ((ep->bstate & BUTTON_CLICKED)
&& (next->bstate & BUTTON_CLICKED)) {
merge = FALSE;
for (b = 1; b <= MAX_BUTTONS; ++b) {
if ((sp->_mouse_mask & MASK_DOUBLE_CLICK(b))
&& (ep->bstate & MASK_CLICK(b))
&& (next->bstate & MASK_CLICK(b))) {
next->bstate &= ~MASK_CLICK(b);
next->bstate |= MASK_DOUBLE_CLICK(b);
merge = TRUE;
}
}
if (merge) {
Invalidate(ep);
}
}
/* merge double-click events forward */
if ((ep->bstate & BUTTON_DOUBLE_CLICKED)
&& (next->bstate & BUTTON_CLICKED)) {
merge = FALSE;
for (b = 1; b <= MAX_BUTTONS; ++b) {
if ((sp->_mouse_mask & MASK_TRIPLE_CLICK(b))
&& (ep->bstate & MASK_DOUBLE_CLICK(b))
&& (next->bstate & MASK_CLICK(b))) {
next->bstate &= ~MASK_CLICK(b);
next->bstate |= MASK_TRIPLE_CLICK(b);
merge = TRUE;
}
}
if (merge) {
Invalidate(ep);
}
}
}
/* Discard event if it does not match event mask */
if (!(ep->bstate & sp->_mouse_mask2)) {
Invalidate(ep);
}
/* Compact valid events */
if (!ValidEvent(ep)) {
if (ep == first_valid) {
first_valid = next;
} else if (first_invalid == NULL) {
first_invalid = ep;
}
} else if (first_invalid != NULL) {
*first_invalid = *ep;
Invalidate(ep);
first_invalid = NEXT(first_invalid);
}
ep = next;
}
if (first_invalid == NULL) {
first_invalid = eventp;
}
sp->_mouse_eventp = first_invalid;
#ifdef TRACE
if (first_valid != NULL) {
if (USE_TRACEF(TRACE_IEVENT)) {
_trace_slot(sp, "after mouse event queue compaction:");
_tracef("_nc_mouse_parse: run starts at %ld, ends at %ld, count %d",
RunParams(sp, first_invalid, first_valid),
runcount);
_nc_unlock_global(tracef);
}
for (ep = first_valid; ep != first_invalid; ep = NEXT(ep)) {
if (ValidEvent(ep))
TR(MY_TRACE,
("_nc_mouse_parse: returning composite mouse event %s at slot %ld",
_nc_tracemouse(sp, ep),
(long) IndexEV(sp, ep)));
}
}
#endif /* TRACE */
/* after all this, do we have a valid event? */
return ValidEvent(PREV(first_invalid));
}