diff options
Diffstat (limited to 'libX11/src/XlibInt.c')
| -rw-r--r-- | libX11/src/XlibInt.c | 183 |
1 files changed, 181 insertions, 2 deletions
diff --git a/libX11/src/XlibInt.c b/libX11/src/XlibInt.c index 320e80800..9505b3f18 100644 --- a/libX11/src/XlibInt.c +++ b/libX11/src/XlibInt.c @@ -2258,6 +2258,128 @@ void _XEatData( } #endif /* !USE_XCB */ +/* Cookie jar implementation + dpy->cookiejar is a linked list. _XEnq receives the events but leaves + them in the normal EQ. _XStoreEvent returns the cookie event (minus + data pointer) and adds it to the cookiejar. _XDeq just removes + the entry like any other event but resets the data pointer for + cookie events (to avoid double-free, the memory is re-used by Xlib). + + _XFetchEventCookie (called from XGetEventData) removes a cookie from the + jar. _XFreeEventCookies removes all unclaimed cookies from the jar + (called by XNextEvent). + + _XFreeDisplayStructure calls _XFreeEventCookies for each cookie in the + normal EQ. + */ + +#include "utlist.h" +struct stored_event { + XGenericEventCookie ev; + struct stored_event *prev; + struct stored_event *next; +}; + +Bool +_XIsEventCookie(Display *dpy, XEvent *ev) +{ + return (ev->xcookie.type == GenericEvent && + dpy->generic_event_vec[ev->xcookie.extension & 0x7F] != NULL); +} + +/** + * Free all events in the event list. + */ +void +_XFreeEventCookies(Display *dpy) +{ + struct stored_event **head, *e, *tmp; + + if (!dpy->cookiejar) + return; + + head = (struct stored_event**)&dpy->cookiejar; + + DL_FOREACH_SAFE(*head, e, tmp) { + XFree(e->ev.data); + XFree(e); + if (dpy->cookiejar == e) + dpy->cookiejar = NULL; + } +} + +/** + * Add an event to the display's event list. This event must be freed on the + * next call to XNextEvent(). + */ +void +_XStoreEventCookie(Display *dpy, XEvent *event) +{ + XGenericEventCookie* cookie = &event->xcookie; + struct stored_event **head, *add; + + if (!_XIsEventCookie(dpy, event)) + return; + + head = (struct stored_event**)(&dpy->cookiejar); + + add = Xmalloc(sizeof(struct stored_event)); + if (!add) { + ESET(ENOMEM); + _XIOError(dpy); + } + add->ev = *cookie; + DL_APPEND(*head, add); + cookie->data = NULL; /* don't return data yet, must be claimed */ +} + +/** + * Return the event with the given cookie and remove it from the list. + */ +Bool +_XFetchEventCookie(Display *dpy, XGenericEventCookie* ev) +{ + Bool ret = False; + struct stored_event **head, *event; + head = (struct stored_event**)&dpy->cookiejar; + + if (!_XIsEventCookie(dpy, (XEvent*)ev)) + return ret; + + DL_FOREACH(*head, event) { + if (event->ev.cookie == ev->cookie && + event->ev.extension == ev->extension && + event->ev.evtype == ev->evtype) { + *ev = event->ev; + DL_DELETE(*head, event); + Xfree(event); + ret = True; + break; + } + } + + return ret; +} + +Bool +_XCopyEventCookie(Display *dpy, XGenericEventCookie *in, XGenericEventCookie *out) +{ + Bool ret = False; + int extension; + + if (!_XIsEventCookie(dpy, (XEvent*)in) || !out) + return ret; + + extension = in->extension & 0x7F; + + if (!dpy->generic_event_copy_vec[extension]) + return ret; + + ret = ((*dpy->generic_event_copy_vec[extension])(dpy, in, out)); + out->cookie = ret ? ++dpy->next_cookie : 0; + return ret; +} + /* * _XEnq - Place event packets on the display's queue. @@ -2269,6 +2391,7 @@ void _XEnq( register xEvent *event) { register _XQEvent *qelt; + int type, extension; if ((qelt = dpy->qfree)) { /* If dpy->qfree is non-NULL do this, else malloc a new one. */ @@ -2281,8 +2404,29 @@ void _XEnq( _XIOError(dpy); } qelt->next = NULL; - /* go call through display to find proper event reformatter */ - if ((*dpy->event_vec[event->u.u.type & 0177])(dpy, &qelt->event, event)) { + + type = event->u.u.type & 0177; + extension = ((xGenericEvent*)event)->extension; + /* If an extension has registerd a generic_event_vec handler, then + * it can handle event cookies. Otherwise, proceed with the normal + * event handlers. + * + * If the generic_event_vec is called, qelt->event is a event cookie + * with the data pointer and the "free" pointer set. Data pointer is + * some memory allocated by the extension. + */ + if (type == GenericEvent && dpy->generic_event_vec[extension & 0x7F]) { + XGenericEventCookie *cookie = &qelt->event.xcookie; + (*dpy->generic_event_vec[extension & 0x7F])(dpy, cookie, event); + cookie->cookie = ++dpy->next_cookie; + + qelt->qserial_num = dpy->next_event_serial_num++; + if (dpy->tail) dpy->tail->next = qelt; + else dpy->head = qelt; + + dpy->tail = qelt; + dpy->qlen++; + } else if ((*dpy->event_vec[type])(dpy, &qelt->event, event)) { qelt->qserial_num = dpy->next_event_serial_num++; if (dpy->tail) dpy->tail->next = qelt; else dpy->head = qelt; @@ -2316,6 +2460,13 @@ void _XDeq( qelt->next = dpy->qfree; dpy->qfree = qelt; dpy->qlen--; + + if (_XIsEventCookie(dpy, &qelt->event)) { + XGenericEventCookie* cookie = &qelt->event.xcookie; + /* dpy->qfree is re-used, reset memory to avoid double free on + * _XFreeDisplayStructure */ + cookie->data = NULL; + } } /* @@ -2337,6 +2488,34 @@ _XUnknownWireEvent( return(False); } +Bool +_XUnknownWireEventCookie( + Display *dpy, /* pointer to display structure */ + XGenericEventCookie *re, /* pointer to where event should be reformatted */ + xEvent *event) /* wire protocol event */ +{ +#ifdef notdef + fprintf(stderr, + "Xlib: unhandled wire cookie event! extension number = %d, display = %x\n.", + ((xGenericEvent*)event)->extension, dpy); +#endif + return(False); +} + +Bool +_XUnknownCopyEventCookie( + Display *dpy, /* pointer to display structure */ + XGenericEventCookie *in, /* source */ + XGenericEventCookie *out) /* destination */ +{ +#ifdef notdef + fprintf(stderr, + "Xlib: unhandled cookie event copy! extension number = %d, display = %x\n.", + in->extension, dpy); +#endif + return(False); +} + /*ARGSUSED*/ Status _XUnknownNativeEvent( |