| 1 | /* |
| 2 | SDL - Simple DirectMedia Layer |
| 3 | Copyright (C) 1997-2009 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 | |
| 45 | UInt64 start; |
| 46 | |
| 47 | void 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 | |
| 59 | Uint32 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 | |
| 71 | void 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 */ |
| 88 | typedef struct _ExtendedTimerRec |
| 89 | { |
| 90 | TMTask tmTask; |
| 91 | ProcessSerialNumber taskPSN; |
| 92 | } ExtendedTimerRec, *ExtendedTimerPtr; |
| 93 | |
| 94 | static ExtendedTimerRec gExtendedTimerRec; |
| 95 | |
| 96 | |
| 97 | int SDL_SYS_TimerInit(void) |
| 98 | { |
| 99 | /* We don't need a setup? */ |
| 100 | return(0); |
| 101 | } |
| 102 | |
| 103 | void 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. */ |
| 110 | pascal 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 | |
| 126 | int 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 | |
| 147 | void SDL_SYS_StopTimer(void) |
| 148 | { |
| 149 | RmvTime((QElemPtr)&gExtendedTimerRec.tmTask); |
| 150 | } |
| 151 | |
| 152 | #endif /* SDL_TIMER_MACOS */ |