test/testlock.c
author Patrice Mandin <patmandin@gmail.com>
Thu, 19 Jan 2006 21:28:52 +0000
changeset 1257 448a9a64537b
parent 1151 be9c9c8f6d53
child 1659 14717b52abc0
permissions -rw-r--r--
[PATCH] SDL_GetVideoMode() does not find best mode, part 2

Following commit 1.51, I come accross a problem when SDL must choose between
several video modes that could suit the one asked.

If I ask 320x240 with this list:
768x480 768x240 640x400 640x200 384x480 384x240 320x400 320x200

The smallest selectables modes are 384x240 and 320x400. And SDL choose the later
in this list, but 384x240 is more suitable. So I added a check to compare
the pixel count (surface) of modes, and select the one which has the smallest
pixel count.

In my example, 384x240 has 92160 pixels, and 320x400 has 128000 pixels. So now
SDL will choose 384x240 for the asked 320x240 mode.
     1 
     2 /* Test the thread and mutex locking functions 
     3    Also exercises the system's signal/thread interaction
     4 */
     5 
     6 #include <signal.h>
     7 #include <stdio.h>
     8 #include <stdlib.h>
     9 
    10 #include "SDL.h"
    11 #include "SDL_mutex.h"
    12 #include "SDL_thread.h"
    13 
    14 static SDL_mutex *mutex = NULL;
    15 static Uint32 mainthread;
    16 static SDL_Thread *threads[6];
    17 
    18 /*
    19  * SDL_Quit() shouldn't be used with atexit() directly because
    20  *  calling conventions may differ...
    21  */
    22 static void SDL_Quit_Wrapper(void)
    23 {
    24 	SDL_Quit();
    25 }
    26 
    27 void printid(void)
    28 {
    29 	printf("Process %u:  exiting\n", SDL_ThreadID());
    30 }
    31 	
    32 void terminate(int sig)
    33 {
    34 	printf("Process %u:  raising SIGTERM\n", SDL_ThreadID());
    35 	raise(SIGTERM);
    36 }
    37 void closemutex(int sig)
    38 {
    39 	Uint32 id = SDL_ThreadID();
    40 	int i;
    41 	printf("Process %u:  Cleaning up...\n", id == mainthread ? 0 : id);
    42 	for ( i=0; i<6; ++i )
    43 		SDL_KillThread(threads[i]);
    44 	SDL_DestroyMutex(mutex);
    45 	exit(sig);
    46 }
    47 int Run(void *data)
    48 {
    49 	if ( SDL_ThreadID() == mainthread )
    50 		signal(SIGTERM, closemutex);
    51 	while ( 1 ) {
    52 		printf("Process %u ready to work\n", SDL_ThreadID());
    53 		if ( SDL_mutexP(mutex) < 0 ) {
    54 			fprintf(stderr, "Couldn't lock mutex: %s", SDL_GetError());
    55 			exit(1);
    56 		}
    57 		printf("Process %u, working!\n", SDL_ThreadID());
    58 		SDL_Delay(1*1000);
    59 		printf("Process %u, done!\n", SDL_ThreadID());
    60 		if ( SDL_mutexV(mutex) < 0 ) {
    61 			fprintf(stderr, "Couldn't unlock mutex: %s", SDL_GetError());
    62 			exit(1);
    63 		}
    64 		/* If this sleep isn't done, then threads may starve */
    65 		SDL_Delay(10);
    66 	}
    67 	return(0);
    68 }
    69 
    70 int main(int argc, char *argv[])
    71 {
    72 	int i;
    73 	int maxproc = 6;
    74 
    75 	/* Load the SDL library */
    76 	if ( SDL_Init(0) < 0 ) {
    77 		fprintf(stderr, "%s\n", SDL_GetError());
    78 		exit(1);
    79 	}
    80 	atexit(SDL_Quit_Wrapper);
    81 
    82 	if ( (mutex=SDL_CreateMutex()) == NULL ) {
    83 		fprintf(stderr, "Couldn't create mutex: %s\n", SDL_GetError());
    84 		exit(1);
    85 	}
    86 
    87 	mainthread = SDL_ThreadID();
    88 	printf("Main thread: %u\n", mainthread);
    89 	atexit(printid);
    90 	for ( i=0; i<maxproc; ++i ) {
    91 		if ( (threads[i]=SDL_CreateThread(Run, NULL)) == NULL )
    92 			fprintf(stderr, "Couldn't create thread!\n");
    93 	}
    94 	signal(SIGINT, terminate);
    95 	Run(NULL);
    96 
    97 	return(0);	/* Never reached */
    98 }