Mercurial > sdl-ios-xcode
view test/testlock.c @ 1157:baf35853ad54
Date: Mon, 10 Oct 2005 13:09:32 +0300
From: Tommi Kyntola <tommi.kyntola@ray.fi>
To: sdl@libsdl.org
Subject: [SDL] [RFC] get_ticks broken on linux
It uses gettimeofday to calculate the timedifference.
Gettimeofday returns current time which is seldom monotonous.
This breaks SDL timer subsystem. (time callbacks and all that
get borked when the time difference ms is suddenly ~ 2^32)
I posted a message about this earlier but got no response.
Some thoughts on this matter would be appreciated.
(Or even an explanation for the lack of interest.)
A patch below would use the posix timers that have been around
since posix 93 and do provide a good source of monotonous time
on linux boxes (and on few others too).
The following patch is also availabe at:
http://www.hut.fi/u/tkyntola/SDL-1.2.9-clockfix.patch
It's against 1.2.9, but I can easily rediffit against
the cvs branch is needed.
cheers,
Tommi Kyntola tommi.kyntola@ray.fi
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Tue, 11 Oct 2005 18:16:12 +0000 |
parents | be9c9c8f6d53 |
children | 14717b52abc0 |
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/* Test the thread and mutex locking functions Also exercises the system's signal/thread interaction */ #include <signal.h> #include <stdio.h> #include <stdlib.h> #include "SDL.h" #include "SDL_mutex.h" #include "SDL_thread.h" static SDL_mutex *mutex = NULL; static Uint32 mainthread; static SDL_Thread *threads[6]; /* * SDL_Quit() shouldn't be used with atexit() directly because * calling conventions may differ... */ static void SDL_Quit_Wrapper(void) { SDL_Quit(); } void printid(void) { printf("Process %u: exiting\n", SDL_ThreadID()); } void terminate(int sig) { printf("Process %u: raising SIGTERM\n", SDL_ThreadID()); raise(SIGTERM); } void closemutex(int sig) { Uint32 id = SDL_ThreadID(); int i; printf("Process %u: Cleaning up...\n", id == mainthread ? 0 : id); for ( i=0; i<6; ++i ) SDL_KillThread(threads[i]); SDL_DestroyMutex(mutex); exit(sig); } int Run(void *data) { if ( SDL_ThreadID() == mainthread ) signal(SIGTERM, closemutex); while ( 1 ) { printf("Process %u ready to work\n", SDL_ThreadID()); if ( SDL_mutexP(mutex) < 0 ) { fprintf(stderr, "Couldn't lock mutex: %s", SDL_GetError()); exit(1); } printf("Process %u, working!\n", SDL_ThreadID()); SDL_Delay(1*1000); printf("Process %u, done!\n", SDL_ThreadID()); if ( SDL_mutexV(mutex) < 0 ) { fprintf(stderr, "Couldn't unlock mutex: %s", SDL_GetError()); exit(1); } /* If this sleep isn't done, then threads may starve */ SDL_Delay(10); } return(0); } int main(int argc, char *argv[]) { int i; int maxproc = 6; /* Load the SDL library */ if ( SDL_Init(0) < 0 ) { fprintf(stderr, "%s\n", SDL_GetError()); exit(1); } atexit(SDL_Quit_Wrapper); if ( (mutex=SDL_CreateMutex()) == NULL ) { fprintf(stderr, "Couldn't create mutex: %s\n", SDL_GetError()); exit(1); } mainthread = SDL_ThreadID(); printf("Main thread: %u\n", mainthread); atexit(printid); for ( i=0; i<maxproc; ++i ) { if ( (threads[i]=SDL_CreateThread(Run, NULL)) == NULL ) fprintf(stderr, "Couldn't create thread!\n"); } signal(SIGINT, terminate); Run(NULL); return(0); /* Never reached */ }