mdw@git.distorted.org.uk Git - ssr/blob - StraySrc/Libraries/Steel/c/blinkC

   1 /*
   2  * BlinkCursor
   3  *  A nice blinky caret routine for your progs
   4  *
   5  * v. 1.00 (23 July 1993)
   6  *
   7  * © 1993-1998 Straylight
   8  */
   9
  10 /*----- Licensing note ----------------------------------------------------*
  11  *
  12  * This file is part of Straylight's Steel library.
  13  *
  14  * Steel is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  * Steel is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with Steel.  If not, write to the Free Software Foundation,
  26  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 #include "wimp.h"
  30 #include "wimpt.h"
  31 #include "os.h"
  32 #include "blinkC.h"
  33 #include "alarm.h"
  34 #include "swiv.h"
  35 #include <stdlib.h>
  36
  37 #include "dll.h"
  38
  39 #ifndef _dll_NODLL
  40   extern void _dllEntry(blink__exit)(void);
  41   extern void _dllEntry(blink__doBlink)(int at,void *handle);
  42 #endif
  43
  44 /*
  45  * A handle thing for alarm.  It's not used by the routine, but it helps
  46  * identify the alarm routine to be removed.
  47  */
  48 #define blink__MYHANDLE (void *)&blink__onAlready
  49
  50 /*
  51  * The SWI number for Wimp_SendMessage.
  52  */
  53 #define Wimp_SendMessage 0x600E7
  54
  55 /*
  56  * Due to circular definitions, I am forced to add in a prototype for this
  57  * function.
  58  */
  59 static void blink__setupAlarm(void);
  60
  61 /*
  62  * A flag to say whether we are on already or not.
  63  */
  64 static BOOL blink__onAlready;
  65
  66 /*
  67  * A flag to say whether the caret is visible or not.
  68  */
  69 static BOOL blink__caretVisible;
  70
  71 /*
  72  * void blink__onCaret(void)
  73  *
  74  * Use
  75  *  Makes the caret visible.
  76  */
  77
  78 static void blink__onCaret(void)
  79 {
  80   wimp_caretstr c;
  81   wimpt_noerr(wimp_get_caret_pos(&c));
  82   c.height &= ~(1<<25);
  83   wimpt_noerr(wimp_set_caret_pos(&c));
  84   blink__caretVisible=TRUE;
  85 }
  86
  87 /*
  88  * void blink__offCaret(void)
  89  *
  90  * Use
  91  *  Makes the caret invisible.
  92  */
  93
  94 static void blink__offCaret(void)
  95 {
  96   wimp_caretstr c;
  97   wimpt_noerr(wimp_get_caret_pos(&c));
  98   c.height |= 1<<25;
  99   wimpt_noerr(wimp_set_caret_pos(&c));
 100   blink__caretVisible=FALSE;
 101 }
 102
 103 /*
 104  * BOOL blink__ownCaret(void)
 105  *
 106  * Use
 107  *  Returns whether the task owns the caret or not!
 108  *
 109  * Returns
 110  *  TRUE if it does.
 111  */
 112
 113 static BOOL blink__ownCaret(void)
 114 {
 115   wimp_caretstr c;
 116   wimp_msgstr m;
 117   int task;
 118   wimpt_noerr(wimp_get_caret_pos(&c));
 119   if (c.w<=0)
 120     return (FALSE);
 121   m.hdr.size=20;
 122   m.hdr.your_ref=0;
 123   _swix(Wimp_SendMessage, _inr(0,2)+_out(2), 19,&m,c.w, &task);
 124   return (task==wimpt_task());
 125 }
 126
 127 _dll_static void blink__doBlink(int at,void *handle)
 128 {
 129   handle=handle;
 130   at=at;
 131   if (blink__ownCaret())
 132   {
 133     switch (blink__caretVisible)
 134     {
 135       case TRUE:
 136         blink__offCaret();
 137         break;
 138       case FALSE:
 139         blink__onCaret();
 140         break;
 141     }
 142   }
 143   blink__setupAlarm();
 144 }
 145
 146 /*
 147  * void blink__setupAlarm(void)
 148  *
 149  * Use
 150  *  Sets up next alarm ready.
 151  */
 152
 153 static void blink__setupAlarm(void)
 154 {
 155   int nextTime=((alarm_timenow()/25)*25)+25;
 156   alarm_set(nextTime,_dllEntry(blink__doBlink),blink__MYHANDLE);
 157 }
 158
 159 /*
 160  * void blinkCursor(BOOL onOrOff)
 161  *
 162  * Use
 163  *  Turns the blinkingness of the cursor on or off.  You must call
 164  *  alarm_init() before this function, or all hell breaks loose.
 165  *
 166  * Parameters
 167  *  BOOL onOrOff == whether you want to turn blinking cursor on or off
 168  */
 169
 170 void blinkCursor(BOOL onOrOff)
 171 {
 172   if (onOrOff==blink__onAlready)
 173     return;
 174   switch (onOrOff)
 175   {
 176     case TRUE:
 177       blink__setupAlarm();
 178       blink__onAlready=TRUE;
 179       break;
 180     case FALSE:
 181       if (blink__ownCaret())
 182         blink__onCaret();
 183       alarm_removeall(blink__MYHANDLE);
 184       blink__onAlready=FALSE;
 185       break;
 186   }
 187 }
 188
 189 /*
 190  * void blink__exit(void)
 191  *
 192  * Use
 193  *  Turns off the caret blinking.
 194  */
 195
 196 _dll_static void blink__exit(void)
 197 {
 198   blinkCursor(FALSE);
 199 }
 200
 201 /*
 202  * void blink_init(void)
 203  *
 204  * Use
 205  *  Sets everything up nicely.
 206  */
 207
 208 void blink_init(void)
 209 {
 210   atexit(_dllEntry(blink__exit));
 211 }