11ab64890Smrg/* 21ab64890Smrg 31ab64890SmrgCopyright 1985, 1987, 1998 The Open Group 41ab64890Smrg 51ab64890SmrgPermission to use, copy, modify, distribute, and sell this software and its 61ab64890Smrgdocumentation for any purpose is hereby granted without fee, provided that 71ab64890Smrgthe above copyright notice appear in all copies and that both that 81ab64890Smrgcopyright notice and this permission notice appear in supporting 91ab64890Smrgdocumentation. 101ab64890Smrg 111ab64890SmrgThe above copyright notice and this permission notice shall be included in 121ab64890Smrgall copies or substantial portions of the Software. 131ab64890Smrg 141ab64890SmrgTHE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 151ab64890SmrgIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 161ab64890SmrgFITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 171ab64890SmrgOPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN 181ab64890SmrgAN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 191ab64890SmrgCONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 201ab64890Smrg 211ab64890SmrgExcept as contained in this notice, the name of The Open Group shall not be 221ab64890Smrgused in advertising or otherwise to promote the sale, use or other dealings 231ab64890Smrgin this Software without prior written authorization from The Open Group. 241ab64890Smrg 251ab64890Smrg*/ 261ab64890Smrg 271ab64890Smrg#ifdef HAVE_CONFIG_H 281ab64890Smrg#include <config.h> 291ab64890Smrg#endif 301ab64890Smrg#include "Xlibint.h" 311ab64890Smrg 3261b2299dSmrg/* 331ab64890Smrg * Check existing events in queue to find if any match. If so, return. 341ab64890Smrg * If not, flush buffer and see if any more events are readable. If one 351ab64890Smrg * matches, return. If all else fails, tell the user no events found. 361ab64890Smrg */ 371ab64890Smrg 381ab64890SmrgBool XCheckIfEvent ( 391ab64890Smrg register Display *dpy, 401ab64890Smrg register XEvent *event, /* XEvent to be filled in. */ 411ab64890Smrg Bool (*predicate)( 421ab64890Smrg Display* /* display */, 431ab64890Smrg XEvent* /* event */, 441ab64890Smrg char* /* arg */ 451ab64890Smrg ), /* function to call */ 461ab64890Smrg char *arg) 471ab64890Smrg{ 481ab64890Smrg register _XQEvent *prev, *qelt; 491ab64890Smrg unsigned long qe_serial = 0; 501ab64890Smrg int n; /* time through count */ 511ab64890Smrg 520efe039aSmartin LockDisplay(dpy); 53876003caSmrg#ifdef XTHREADS 54876003caSmrg dpy->ifevent_thread = xthread_self(); 55876003caSmrg#endif 56876003caSmrg dpy->in_ifevent++; 571ab64890Smrg prev = NULL; 581ab64890Smrg for (n = 3; --n >= 0;) { 591ab64890Smrg for (qelt = prev ? prev->next : dpy->head; 601ab64890Smrg qelt; 611ab64890Smrg prev = qelt, qelt = qelt->next) { 621ab64890Smrg if(qelt->qserial_num > qe_serial 631ab64890Smrg && (*predicate)(dpy, &qelt->event, arg)) { 641ab64890Smrg *event = qelt->event; 651ab64890Smrg _XDeq(dpy, prev, qelt); 66b4ee4795Smrg _XStoreEventCookie(dpy, event); 670efe039aSmartin dpy->in_ifevent--; 681ab64890Smrg UnlockDisplay(dpy); 691ab64890Smrg return True; 701ab64890Smrg } 711ab64890Smrg } 721ab64890Smrg if (prev) 731ab64890Smrg qe_serial = prev->qserial_num; 741ab64890Smrg switch (n) { 751ab64890Smrg case 2: 761ab64890Smrg _XEventsQueued(dpy, QueuedAfterReading); 771ab64890Smrg break; 781ab64890Smrg case 1: 791ab64890Smrg _XFlush(dpy); 801ab64890Smrg break; 811ab64890Smrg } 821ab64890Smrg if (prev && prev->qserial_num != qe_serial) 831ab64890Smrg /* another thread has snatched this event */ 841ab64890Smrg prev = NULL; 851ab64890Smrg } 860efe039aSmartin dpy->in_ifevent--; 871ab64890Smrg UnlockDisplay(dpy); 881ab64890Smrg return False; 891ab64890Smrg} 90