Mercurial > sdl-ios-xcode
annotate test/testtimer.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 | b2b476a4a73c |
| rev | line source |
|---|---|
| 0 | 1 |
| 2 /* Test program to check the resolution of the SDL timer on the current | |
| 3 platform | |
| 4 */ | |
| 5 | |
| 6 #include <stdlib.h> | |
| 7 #include <stdio.h> | |
| 8 | |
| 9 #include "SDL.h" | |
| 10 | |
| 11 #define DEFAULT_RESOLUTION 1 | |
| 12 | |
| 13 static int ticks = 0; | |
| 14 | |
|
1151
be9c9c8f6d53
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
Ryan C. Gordon <icculus@icculus.org>
parents:
766
diff
changeset
|
15 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */ |
|
be9c9c8f6d53
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
Ryan C. Gordon <icculus@icculus.org>
parents:
766
diff
changeset
|
16 static void quit(int rc) |
|
be9c9c8f6d53
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
Ryan C. Gordon <icculus@icculus.org>
parents:
766
diff
changeset
|
17 { |
|
be9c9c8f6d53
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
Ryan C. Gordon <icculus@icculus.org>
parents:
766
diff
changeset
|
18 SDL_Quit(); |
|
be9c9c8f6d53
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
Ryan C. Gordon <icculus@icculus.org>
parents:
766
diff
changeset
|
19 exit(rc); |
|
be9c9c8f6d53
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
Ryan C. Gordon <icculus@icculus.org>
parents:
766
diff
changeset
|
20 } |
|
be9c9c8f6d53
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
Ryan C. Gordon <icculus@icculus.org>
parents:
766
diff
changeset
|
21 |
| 0 | 22 static Uint32 ticktock(Uint32 interval) |
| 23 { | |
| 24 ++ticks; | |
| 25 return(interval); | |
| 26 } | |
| 27 | |
| 28 static Uint32 callback(Uint32 interval, void *param) | |
| 29 { | |
| 30 printf("Timer %d : param = %d\n", interval, (int) param); | |
| 31 return interval; | |
| 32 } | |
| 33 | |
| 34 int main(int argc, char *argv[]) | |
| 35 { | |
| 36 int desired; | |
| 37 SDL_TimerID t1, t2, t3; | |
| 38 | |
| 39 if ( SDL_Init(SDL_INIT_TIMER) < 0 ) { | |
| 40 fprintf(stderr, "Couldn't load SDL: %s\n", SDL_GetError()); | |
|
1151
be9c9c8f6d53
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
Ryan C. Gordon <icculus@icculus.org>
parents:
766
diff
changeset
|
41 return(1); |
| 0 | 42 } |
| 43 | |
| 44 /* Start the timer */ | |
| 45 desired = 0; | |
| 46 if ( argv[1] ) { | |
| 47 desired = atoi(argv[1]); | |
| 48 } | |
| 49 if ( desired == 0 ) { | |
| 50 desired = DEFAULT_RESOLUTION; | |
| 51 } | |
| 52 SDL_SetTimer(desired, ticktock); | |
| 53 | |
| 54 /* Wait 10 seconds */ | |
| 55 printf("Waiting 10 seconds\n"); | |
| 56 SDL_Delay(10*1000); | |
| 57 | |
| 58 /* Stop the timer */ | |
| 59 SDL_SetTimer(0, NULL); | |
| 60 | |
| 61 /* Print the results */ | |
| 62 if ( ticks ) { | |
| 63 fprintf(stderr, | |
| 64 "Timer resolution: desired = %d ms, actual = %f ms\n", | |
| 65 desired, (double)(10*1000)/ticks); | |
| 66 } | |
| 67 | |
| 68 /* Test multiple timers */ | |
| 69 printf("Testing multiple timers...\n"); | |
| 70 t1 = SDL_AddTimer(100, callback, (void*)1); | |
| 71 if(!t1) | |
|
766
ed57c876700d
Date: Wed, 26 Nov 2003 01:52:02 +0800
Sam Lantinga <slouken@libsdl.org>
parents:
0
diff
changeset
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72 fprintf(stderr,"Could not create timer 1: %s\n", SDL_GetError()); |
| 0 | 73 t2 = SDL_AddTimer(50, callback, (void*)2); |
| 74 if(!t2) | |
|
766
ed57c876700d
Date: Wed, 26 Nov 2003 01:52:02 +0800
Sam Lantinga <slouken@libsdl.org>
parents:
0
diff
changeset
|
75 fprintf(stderr,"Could not create timer 2: %s\n", SDL_GetError()); |
| 0 | 76 t3 = SDL_AddTimer(233, callback, (void*)3); |
| 77 if(!t3) | |
|
766
ed57c876700d
Date: Wed, 26 Nov 2003 01:52:02 +0800
Sam Lantinga <slouken@libsdl.org>
parents:
0
diff
changeset
|
78 fprintf(stderr,"Could not create timer 3: %s\n", SDL_GetError()); |
| 0 | 79 |
| 80 /* Wait 10 seconds */ | |
| 81 printf("Waiting 10 seconds\n"); | |
| 82 SDL_Delay(10*1000); | |
| 83 | |
| 84 printf("Removing timer 1 and waiting 5 more seconds\n"); | |
| 85 SDL_RemoveTimer(t1); | |
| 86 | |
| 87 SDL_Delay(5*1000); | |
| 88 | |
| 89 SDL_RemoveTimer(t2); | |
| 90 SDL_RemoveTimer(t3); | |
| 91 | |
|
1151
be9c9c8f6d53
Removed atexit() from most of the test programs; atexit(SDL_Quit) isn't safe
Ryan C. Gordon <icculus@icculus.org>
parents:
766
diff
changeset
|
92 SDL_Quit(); |
| 0 | 93 return(0); |
| 94 } |