Mercurial > sdl-ios-xcode
view test/testsem.c @ 615:7ec821f3cbd0
Date: Thu, 17 Apr 2003 23:27:34 -0400
From: Darrell Walisser
Subject: Yet another OS X cursor bug
The synopsis:
1. Call SDL_ShowCursor(0);
2. Call SDL_SetVideoMode();
3. Call SDL_GetEvent();
3. Call SDL_ShowCursor(1);
The result: Sometimes the cursor doesn't come back! Ack! Oddly enough,
it does come back when mousing over the dock or clicking in the menu
bar. But that's besides the point.
The reason why this is happening is a flaw in the handling of
activation/deactivation events. The short explanation is that the
HideCursor() and ShowCursor() calls must be balanced, but if the cursor
was initially hidden, HideCursor() was called again on the activate
event - so now the next ShowCursor() fails (as does the next, and the
next, for some reason).
So, here's the patch. All it does is keep track of the
HideCursor()/ShowCursor() calls so that they will always be balanced.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sun, 20 Apr 2003 05:41:16 +0000 |
parents | 74212992fb08 |
children | be9c9c8f6d53 |
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/* Simple test of the SDL semaphore code */ #include <stdio.h> #include <stdlib.h> #include <signal.h> #include "SDL.h" #include "SDL_thread.h" #define NUM_THREADS 10 static SDL_sem *sem; int alive = 1; int ThreadFunc(void *data) { while ( alive ) { SDL_SemWait(sem); fprintf(stderr, "Thread number %d has got the semaphore (value = %d)!\n", (int)data, SDL_SemValue(sem)); SDL_Delay(200); SDL_SemPost(sem); fprintf(stderr, "Thread number %d has released the semaphore (value = %d)!\n", (int)data, SDL_SemValue(sem)); SDL_Delay(1); /* For the scheduler */ } printf("Thread number %d exiting.\n", (int)data); return 0; } static void killed(int sig) { alive = 0; } int main(int argc, char **argv) { SDL_Thread *threads[NUM_THREADS]; int i, init_sem; if(argc < 2) { fprintf(stderr,"Usage: %s init_value\n", argv[0]); exit(1); } /* Load the SDL library */ if ( SDL_Init(0) < 0 ) { fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError()); exit(1); } atexit(SDL_Quit); signal(SIGTERM, killed); signal(SIGINT, killed); init_sem = atoi(argv[1]); sem = SDL_CreateSemaphore(init_sem); printf("Running %d threads, semaphore value = %d\n", NUM_THREADS, init_sem); /* Create all the threads */ for( i = 0; i < NUM_THREADS; ++i ) { threads[i] = SDL_CreateThread(ThreadFunc, (void*)i); } /* Wait 10 seconds */ SDL_Delay(10 * 1000); /* Wait for all threads to finish */ printf("Waiting for threads to finish\n"); alive = 0; for( i = 0; i < NUM_THREADS; ++i ) { SDL_WaitThread(threads[i], NULL); } printf("Finished waiting for threads\n"); SDL_DestroySemaphore(sem); return(0); }