workbench/demos/simple_timer.c

   1 /*
   2  * Copyright (c) 1992 Commodore-Amiga, Inc.
   3  *
   4  * This example is provided in electronic form by Commodore-Amiga, Inc. for
   5  * use with the "Amiga ROM Kernel Reference Manual: Devices", 3rd Edition,
   6  * published by Addison-Wesley (ISBN 0-201-56775-X).
   7  *
   8  * The "Amiga ROM Kernel Reference Manual: Devices" contains additional
   9  * information on the correct usage of the techniques and operating system
  10  * functions presented in these examples.  The source and executable code
  11  * of these examples may only be distributed in free electronic form, via
  12  * bulletin board or as part of a fully non-commercial and freely
  13  * redistributable diskette.  Both the source and executable code (including
  14  * comments) must be included, without modification, in any copy.  This
  15  * example may not be published in printed form or distributed with any
  16  * commercial product.  However, the programming techniques and support
  17  * routines set forth in these examples may be used in the development
  18  * of original executable software products for Commodore Amiga computers.
  19  *
  20  * All other rights reserved.
  21  *
  22  * This example is provided "as-is" and is subject to change; no
  23  * warranties are made.  All use is at your own risk. No liability or
  24  * responsibility is assumed.
  25  *
  26  *****************************************************************************
  27  *
  28  * Simple_Timer.c
  29  *
  30  * A simple example of using the timer device.
  31  *
  32  * Compile with SAS C 5.10: LC -b1 -cfistq -v -y -L
  33  *
  34  * Run from CLI only
  35  */
  36
  37 #include <exec/types.h>
  38 #include <exec/io.h>
  39 #include <exec/memory.h>
  40 #include <devices/timer.h>
  41
  42 #include <proto/exec.h>
  43 #include <clib/alib_protos.h>
  44 #include <proto/dos.h>
  45
  46 #include <stdio.h>
  47
  48 #ifdef LATTICE
  49 int CXBRK(void) { return(0); }     /* Disable Lattice CTRL/C handling */
  50 int chkabort(void) { return(0); }  /* really */
  51 #endif
  52
  53 /* Our timer sub-routines */
  54 void delete_timer  (struct timerequest *);
  55 LONG get_sys_time  (struct timeval *);
  56 LONG set_new_time  (LONG);
  57 void wait_for_timer(struct timerequest *, struct timeval *);
  58 LONG time_delay    ( struct timeval *, LONG );
  59 struct timerequest *create_timer( ULONG );
  60 void show_time     (ULONG);
  61
  62 struct Library *TimerBase;      /* to get at the time comparison functions */
  63
  64 /* manifest constants -- "never will change" */
  65 #define   SECSPERMIN   (60)
  66 #define   SECSPERHOUR  (60*60)
  67 #define   SECSPERDAY   (60*60*24)
  68
  69 int main(int argc,char **argv)
  70 {
  71 LONG seconds;
  72 struct timerequest *tr;      /* IO block for timer commands */
  73 struct timeval oldtimeval;   /* timevals to store times     */
  74 struct timeval mytimeval;
  75 struct timeval currentval;
  76
  77 printf("\nTimer test\n");
  78
  79 /* sleep for two seconds */
  80 currentval.tv_secs = 2;
  81 currentval.tv_micro = 0;
  82 time_delay( &currentval, UNIT_VBLANK );
  83 printf( "After 2 seconds delay\n" );
  84
  85 /* sleep for four seconds */
  86 currentval.tv_secs = 4;
  87 currentval.tv_micro = 0;
  88 time_delay( &currentval, UNIT_VBLANK );
  89 printf( "After 4 seconds delay\n" );
  90
  91 /* sleep for 500,000 micro-seconds = 1/2 second */
  92 currentval.tv_secs = 0;
  93 currentval.tv_micro = 500000;
  94 time_delay( &currentval, UNIT_MICROHZ );
  95 printf( "After 1/2 second delay\n" );
  96
  97 printf( "DOS Date command shows: " );
  98 (void) Execute( "date", 0, 0 );
  99
 100 /* save what system thinks is the time....we'll advance it temporarily */
 101 get_sys_time( &oldtimeval );
 102 printf("Original system time is:\n");
 103 show_time(oldtimeval.tv_secs );
 104
 105 printf("Setting a new system time\n");
 106
 107 seconds = 1000 * SECSPERDAY + oldtimeval.tv_secs;
 108
 109 set_new_time( seconds );
 110 /* (if user executes the AmigaDOS DATE command now, he will*/
 111 /* see that the time has advanced something over 1000 days */
 112
 113 printf( "DOS Date command now shows: " );
 114 (void) Execute( "date", 0, 0 );
 115
 116 get_sys_time( &mytimeval );
 117 printf( "Current system time is:\n");
 118 show_time(mytimeval.tv_secs);
 119
 120 /* Added the microseconds part to show that time keeps */
 121 /* increasing even though you ask many times in a row  */
 122
 123 printf("Now do three TR_GETSYSTIMEs in a row (notice how the microseconds increase)\n\n");
 124 get_sys_time( &mytimeval );
 125 printf("First TR_GETSYSTIME \t%ld.%ld\n",(long) mytimeval.tv_secs, (long) mytimeval.tv_micro);
 126 get_sys_time( &mytimeval );
 127 printf("Second TR_GETSYSTIME \t%ld.%ld\n",(long) mytimeval.tv_secs, (long) mytimeval.tv_micro);
 128 get_sys_time( &mytimeval );
 129 printf("Third TR_GETSYSTIME \t%ld.%ld\n",(long) mytimeval.tv_secs, (long) mytimeval.tv_micro);
 130
 131 printf( "\nResetting to former time\n" );
 132 set_new_time( oldtimeval.tv_secs );
 133
 134 get_sys_time( &mytimeval );
 135 printf( "Current system time is:\n");
 136 show_time(mytimeval.tv_secs);
 137
 138 /* just shows how to set up for using the timer functions, does not */
 139 /* demonstrate the functions themselves.  (TimerBase must have a    */
 140 /* legal value before AddTime, SubTime or CmpTime are performed.    */
 141 tr = create_timer( UNIT_MICROHZ );
 142 if (tr)
 143     TimerBase = (struct Library *)tr->tr_node.io_Device;
 144 else
 145     printf("Could't create timer with UNIT_MICROHZ\n");
 146
 147 /* and how to clean up afterwards */
 148 TimerBase = (struct Library *)(-1);
 149 delete_timer( tr );
 150
 151 return 0;
 152 }
 153
 154 struct timerequest *create_timer( ULONG unit )
 155 {
 156 /* return a pointer to a timer request.  If any problem, return NULL */
 157 LONG error;
 158 struct MsgPort *timerport;
 159 struct timerequest *TimerIO;
 160
 161 timerport = CreatePort( 0, 0 );
 162 if (timerport == NULL )
 163     return( NULL );
 164
 165 TimerIO = (struct timerequest *)
 166     CreateExtIO( timerport, sizeof( struct timerequest ) );
 167 if (TimerIO == NULL )
 168     {
 169     DeletePort(timerport);   /* Delete message port */
 170     return( NULL );
 171     }
 172
 173 error = OpenDevice( TIMERNAME, unit,(struct IORequest *) TimerIO, 0L );
 174 if (error != 0 )
 175     {
 176     delete_timer( TimerIO );
 177     return( NULL );
 178     }
 179 return( TimerIO );
 180 }
 181
 182 /* more precise timer than AmigaDOS Delay() */
 183 LONG time_delay( struct timeval *tv, LONG unit )
 184 {
 185 struct timerequest *tr;
 186 /* get a pointer to an initialized timer request block */
 187 tr = create_timer( unit );
 188
 189 /* any nonzero return says timedelay routine didn't work. */
 190 if (tr == NULL )
 191     return( -1L );
 192
 193 wait_for_timer( tr, tv );
 194
 195 /* deallocate temporary structures */
 196 delete_timer( tr );
 197 return( 0L );
 198 }
 199
 200 void wait_for_timer(struct timerequest *tr, struct timeval *tv )
 201 {
 202
 203 tr->tr_node.io_Command = TR_ADDREQUEST; /* add a new timer request */
 204
 205 /* structure assignment */
 206 tr->tr_time = *tv;
 207
 208 /* post request to the timer -- will go to sleep till done */
 209 DoIO((struct IORequest *) tr );
 210 }
 211
 212 LONG set_new_time(LONG secs)
 213 {
 214 struct timerequest *tr;
 215 tr = create_timer( UNIT_MICROHZ );
 216
 217 /* non zero return says error */
 218 if (tr == 0 )
 219     return( -1 );
 220
 221 tr->tr_time.tv_secs = secs;
 222 tr->tr_time.tv_micro = 0;
 223 tr->tr_node.io_Command = TR_SETSYSTIME;
 224 DoIO((struct IORequest *) tr );
 225
 226 delete_timer(tr);
 227 return(0);
 228 }
 229
 230 LONG get_sys_time(struct timeval *tv)
 231 {
 232 struct timerequest *tr;
 233 tr = create_timer( UNIT_MICROHZ );
 234
 235 /* non zero return says error */
 236 if (tr == 0 )
 237     return( -1 );
 238
 239 tr->tr_node.io_Command = TR_GETSYSTIME;
 240 DoIO((struct IORequest *) tr );
 241
 242 /* structure assignment */
 243 *tv = tr->tr_time;
 244
 245 delete_timer( tr );
 246 return( 0 );
 247 }
 248
 249 void delete_timer(struct timerequest *tr )
 250 {
 251 struct MsgPort *tp;
 252
 253 if (tr != 0 )
 254     {
 255     tp = tr->tr_node.io_Message.mn_ReplyPort;
 256
 257     if (tp != 0)
 258         DeletePort(tp);
 259
 260     CloseDevice( (struct IORequest *) tr );
 261     DeleteExtIO( (struct IORequest *) tr );
 262     }
 263 }
 264
 265 void show_time(ULONG secs)
 266 {
 267 ULONG days,hrs,mins;
 268
 269 /* Compute days, hours, etc. */
 270 mins=secs/60;
 271 hrs=mins/60;
 272 days=hrs/24;
 273 secs=secs%60;
 274 mins=mins%60;
 275 hrs=hrs%24;
 276
 277 /* Display the time */
 278 printf("*   Hour Minute Second  (Days since Jan.1,1978)\n");
 279 printf("*%5ld:%5ld:%5ld      (%6ld )\n\n",(long)hrs,(long)mins,(long)secs,(long)days);
 280 }      /* end of main */