src/hci/mucurses/kb.c

   1 #include <curses.h>
   2 #include <stddef.h>
   3 #include <unistd.h>
   4 #include "mucurses.h"
   5
   6 /** @file
   7  *
   8  * MuCurses keyboard input handling functions
   9  */
  10
  11 #define INPUT_DELAY             200 // half-blocking delay timer resolution (ms)
  12 #define INPUT_DELAY_TIMEOUT     1000 // half-blocking delay timeout
  13
  14 int m_delay; /*
  15                 < 0 : blocking read
  16                 0   : non-blocking read
  17                 > 0 : timed blocking read
  18              */
  19 bool m_echo;
  20 bool m_cbreak;
  21
  22 static int _wgetc ( WINDOW *win ) {
  23         int timer, c;
  24
  25         if ( win == NULL )
  26                 return ERR;
  27
  28         timer = INPUT_DELAY_TIMEOUT;
  29         while ( ! win->scr->peek( win->scr ) ) {
  30                 if ( m_delay == 0 ) // non-blocking read
  31                         return ERR;
  32                 if ( timer > 0 ) {  // time-limited blocking read
  33                         if ( m_delay > 0 )
  34                                 timer -= INPUT_DELAY;
  35                         mdelay( INPUT_DELAY );
  36                 } else { return ERR; } // non-blocking read
  37         }
  38
  39         c = win->scr->getc( win->scr );
  40
  41         if ( m_echo && ( c >= 32 && c <= 126 ) ) // printable ASCII characters
  42                 _wputch( win, (chtype) ( c | win->attrs ), WRAP );
  43
  44         return c;
  45 }
  46
  47 /**
  48  * Pop a character from the FIFO into a window
  49  *
  50  * @v *win      window in which to echo input
  51  * @ret c       char from input stream
  52  */
  53 int wgetch ( WINDOW *win ) {
  54         int c;
  55
  56         c = _wgetc( win );
  57
  58         if ( m_echo ) {
  59                 if ( c >= KEY_MIN ) {
  60                         switch(c) {
  61                         case KEY_LEFT :
  62                         case KEY_BACKSPACE :
  63                                 _wcursback( win );
  64                                 wdelch( win );
  65                                 break;
  66                         default :
  67                                 beep();
  68                                 break;
  69                         }
  70                 } else {
  71                         _wputch( win, (chtype)( c | win->attrs ), WRAP );
  72                 }
  73         }
  74
  75         return c;
  76 }
  77
  78 /**
  79  * Read at most n characters from the FIFO into a window
  80  *
  81  * @v *win      window in which to echo input
  82  * @v *str      pointer to string in which to store result
  83  * @v n         maximum number of characters to read into string (inc. NUL)
  84  * @ret rc      return status code
  85  */
  86 int wgetnstr ( WINDOW *win, char *str, int n ) {
  87         char *_str;
  88         int c;
  89
  90         if ( n == 0 ) {
  91                 str = '\0';
  92                 return OK;
  93         }
  94
  95         _str = str;
  96
  97         while ( ( c = _wgetc( win ) ) != ERR ) {
  98                 /* termination enforcement - don't let us go past the
  99                    end of the allocated buffer... */
 100                 if ( n == 0 && ( c >= 32 && c <= 126 ) ) {
 101                         _wcursback( win );
 102                         wdelch( win );
 103                 } else {
 104                         if ( c >= KEY_MIN ) {
 105                                 switch(c) {
 106                                 case KEY_LEFT :
 107                                 case KEY_BACKSPACE :
 108                                         _wcursback( win );
 109                                         wdelch( win );
 110                                         break;
 111                                 case KEY_ENTER :
 112                                         *_str = '\0';
 113                                         return OK;
 114                                 default :
 115                                         beep();
 116                                         break;
 117                                 }
 118                         }
 119                         if ( c >= 32 && c <= 126 ) {
 120                                 *(_str++) = c; n--;
 121                         }
 122                 }
 123         }
 124
 125         return ERR;
 126 }
 127
 128
 129 /**
 130  *
 131  */
 132 int echo ( void ) {
 133         m_echo = TRUE;
 134         return OK;
 135 }
 136
 137 /**
 138  *
 139  */
 140 int noecho ( void ) {
 141         m_echo = FALSE;
 142         return OK;
 143 }