view include/SDL_timer.h @ 2079:1ed2155b7ee4

From: Torsten Giebl Subject: ALLOCA Patch for SDL-1.2 Newsgroups: gmane.comp.lib.sdl Date: 2006-10-24 00:31:16 GMT Hello ! As alloca.h is not available on CYGWIN and MinGW32 it should not be checked there or it should be checked with -mno-cygwin using. I am a total configure.in newbie, but i found the way that things are handled in configure.in pretty bad for the case CYGWIN with MinGW Mode or not. Maybe this is not possible but i would like to have a way to detect at the start for example CYGWIN and then add. ask if configure was called with --enable-cygwin for example. --enable-cygwin should be optional and disabled by default as we want to have MinGW Mode by default. Only if the user wants it he should be able to use it. Then the whole configure.in would get add. questions okay the system is CYGWIN with or without MinGW Mode. The alloca.h thing for example is only available under CYGWIN ( without MinGW Mode ). CU
author Ryan C. Gordon <icculus@icculus.org>
date Fri, 01 Dec 2006 20:25:03 +0000
parents c121d94672cb
children 99210400e8b9
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/

#ifndef _SDL_timer_h
#define _SDL_timer_h

/**
 * \file SDL_timer.h
 *
 * Header for the SDL time management routines
 */

#include "SDL_stdinc.h"
#include "SDL_error.h"

#include "begin_code.h"
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
/* *INDENT-OFF* */
extern "C" {
/* *INDENT-ON* */
#endif

/* This is the OS scheduler timeslice, in milliseconds */
#define SDL_TIMESLICE		10

/* This is the maximum resolution of the SDL timer on all platforms */
#define TIMER_RESOLUTION	10      /* Experimentally determined */

/* Get the number of milliseconds since the SDL library initialization.
 * Note that this value wraps if the program runs for more than ~49 days.
 */
extern DECLSPEC Uint32 SDLCALL SDL_GetTicks(void);

/* Wait a specified number of milliseconds before returning */
extern DECLSPEC void SDLCALL SDL_Delay(Uint32 ms);

/* Function prototype for the timer callback function */
typedef Uint32(SDLCALL * SDL_TimerCallback) (Uint32 interval);

/* Set a callback to run after the specified number of milliseconds has
 * elapsed. The callback function is passed the current timer interval
 * and returns the next timer interval.  If the returned value is the 
 * same as the one passed in, the periodic alarm continues, otherwise a
 * new alarm is scheduled.  If the callback returns 0, the periodic alarm
 * is cancelled.
 *
 * To cancel a currently running timer, call SDL_SetTimer(0, NULL);
 *
 * The timer callback function may run in a different thread than your
 * main code, and so shouldn't call any functions from within itself.
 *
 * The maximum resolution of this timer is 10 ms, which means that if
 * you request a 16 ms timer, your callback will run approximately 20 ms
 * later on an unloaded system.  If you wanted to set a flag signaling
 * a frame update at 30 frames per second (every 33 ms), you might set a 
 * timer for 30 ms:
 *   SDL_SetTimer((33/10)*10, flag_update);
 *
 * If you use this function, you need to pass SDL_INIT_TIMER to SDL_Init().
 *
 * Under UNIX, you should not use raise or use SIGALRM and this function
 * in the same program, as it is implemented using setitimer().  You also
 * should not use this function in multi-threaded applications as signals
 * to multi-threaded apps have undefined behavior in some implementations.
 *
 * This function returns 0 if successful, or -1 if there was an error.
 */
extern DECLSPEC int SDLCALL SDL_SetTimer(Uint32 interval,
                                         SDL_TimerCallback callback);

/* New timer API, supports multiple timers
 * Written by Stephane Peter <megastep@lokigames.com>
 */

/* Function prototype for the new timer callback function.
 * The callback function is passed the current timer interval and returns
 * the next timer interval.  If the returned value is the same as the one
 * passed in, the periodic alarm continues, otherwise a new alarm is
 * scheduled.  If the callback returns 0, the periodic alarm is cancelled.
 */
typedef Uint32(SDLCALL * SDL_NewTimerCallback) (Uint32 interval, void *param);

/* Definition of the timer ID type */
typedef struct _SDL_TimerID *SDL_TimerID;

/* Add a new timer to the pool of timers already running.
   Returns a timer ID, or NULL when an error occurs.
 */
extern DECLSPEC SDL_TimerID SDLCALL SDL_AddTimer(Uint32 interval,
                                                 SDL_NewTimerCallback
                                                 callback, void *param);

/* Remove one of the multiple timers knowing its ID.
 * Returns a boolean value indicating success.
 */
extern DECLSPEC SDL_bool SDLCALL SDL_RemoveTimer(SDL_TimerID t);

/* Ends C function definitions when using C++ */
#ifdef __cplusplus
/* *INDENT-OFF* */
}
/* *INDENT-ON* */
#endif
#include "close_code.h"

#endif /* _SDL_timer_h */

/* vi: set ts=4 sw=4 expandtab: */