1/* 2 SDL - Simple DirectMedia Layer 3 Copyright (C) 1997-2012 Sam Lantinga 4 5 This library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 This library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with this library; if not, write to the Free Software 17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 18 19 Sam Lantinga 20 slouken@libsdl.org 21*/ 22#include "SDL_config.h" 23 24#ifdef SDL_TIMER_MACOS 25 26#include <Types.h> 27#include <Timer.h> 28#include <OSUtils.h> 29#include <Gestalt.h> 30#include <Processes.h> 31 32#include <LowMem.h> 33 34#include "SDL_timer.h" 35#include "../SDL_timer_c.h" 36 37#define MS_PER_TICK (1000/60) /* MacOS tick = 1/60 second */ 38 39/* Note: This is only a step above the original 1/60s implementation. 40 * For a good implementation, see FastTimes.[ch], by Matt Slot. 41 */ 42#define USE_MICROSECONDS 43#define WideTo64bit(w) (*(UInt64 *) &(w)) 44 45UInt64 start; 46 47void SDL_StartTicks(void) 48{ 49#ifdef USE_MICROSECONDS 50 UnsignedWide now; 51 52 Microseconds(&now); 53 start = WideTo64bit(now); 54#else 55 /* FIXME: Should we implement a wrapping algorithm, like Win32? */ 56#endif 57} 58 59Uint32 SDL_GetTicks(void) 60{ 61#ifdef USE_MICROSECONDS 62 UnsignedWide now; 63 64 Microseconds(&now); 65 return (Uint32)((WideTo64bit(now)-start)/1000); 66#else 67 return(LMGetTicks()*MS_PER_TICK); 68#endif 69} 70 71void SDL_Delay(Uint32 ms) 72{ 73#ifdef USE_MICROSECONDS 74 Uint32 end_ms; 75 76 end_ms = SDL_GetTicks() + ms; 77 do { 78 /* FIXME: Yield CPU? */ ; 79 } while ( SDL_GetTicks() < end_ms ); 80#else 81 UInt32 unused; /* MJS */ 82 Delay(ms/MS_PER_TICK, &unused); 83#endif 84} 85 86 87/* Data to handle a single periodic alarm */ 88typedef struct _ExtendedTimerRec 89{ 90 TMTask tmTask; 91 ProcessSerialNumber taskPSN; 92} ExtendedTimerRec, *ExtendedTimerPtr; 93 94static ExtendedTimerRec gExtendedTimerRec; 95 96 97int SDL_SYS_TimerInit(void) 98{ 99 /* We don't need a setup? */ 100 return(0); 101} 102 103void SDL_SYS_TimerQuit(void) 104{ 105 /* We don't need a cleanup? */ 106 return; 107} 108 109/* Our Stub routine to set up and then call the real routine. */ 110pascal void TimerCallbackProc(TMTaskPtr tmTaskPtr) 111{ 112 Uint32 ms; 113 114 WakeUpProcess(&((ExtendedTimerPtr) tmTaskPtr)->taskPSN); 115 116 ms = SDL_alarm_callback(SDL_alarm_interval); 117 if ( ms ) { 118 SDL_alarm_interval = ROUND_RESOLUTION(ms); 119 PrimeTime((QElemPtr)&gExtendedTimerRec.tmTask, 120 SDL_alarm_interval); 121 } else { 122 SDL_alarm_interval = 0; 123 } 124} 125 126int SDL_SYS_StartTimer(void) 127{ 128 /* 129 * Configure the global structure that stores the timing information. 130 */ 131 gExtendedTimerRec.tmTask.qLink = NULL; 132 gExtendedTimerRec.tmTask.qType = 0; 133 gExtendedTimerRec.tmTask.tmAddr = NewTimerUPP(TimerCallbackProc); 134 gExtendedTimerRec.tmTask.tmCount = 0; 135 gExtendedTimerRec.tmTask.tmWakeUp = 0; 136 gExtendedTimerRec.tmTask.tmReserved = 0; 137 GetCurrentProcess(&gExtendedTimerRec.taskPSN); 138 139 /* Install the task record */ 140 InsXTime((QElemPtr)&gExtendedTimerRec.tmTask); 141 142 /* Go! */ 143 PrimeTime((QElemPtr)&gExtendedTimerRec.tmTask, SDL_alarm_interval); 144 return(0); 145} 146 147void SDL_SYS_StopTimer(void) 148{ 149 RmvTime((QElemPtr)&gExtendedTimerRec.tmTask); 150} 151 152#endif /* SDL_TIMER_MACOS */ 153