Usermode/Applications/gui_shell_src/vt100.c

   1 /*
   2  * Acess GUI Terminal
   3  * - By John Hodge (thePowersGang)
   4  *
   5  * vt100.c
   6  * - VT100/xterm Emulation
   7  */
   8 #include <string.h>
   9 #include <limits.h>
  10 #include "include/vt100.h"
  11 #include "include/display.h"
  12 #include <ctype.h>      // isalpha
  13 #include <acess/sys.h>  // _SysDebug
  14
  15  int    Term_HandleVT100_Long(int Len, const char *Buf);
  16
  17 static inline int min(int a, int b)
  18 {
  19         return a < b ? a : b;
  20 }
  21
  22 int Term_HandleVT100(int Len, const char *Buf)
  23 {
  24         #define MAX_VT100_ESCAPE_LEN    16
  25         static char     inc_buf[MAX_VT100_ESCAPE_LEN];
  26         static int      inc_len = 0;
  27
  28         if( inc_len > 0 || *Buf == '\x1b' )
  29         {
  30                  int    new_bytes = min(MAX_VT100_ESCAPE_LEN - inc_len, Len);
  31                  int    ret = 0;
  32                 memcpy(inc_buf + inc_len, Buf, new_bytes);
  33                 inc_len += new_bytes;
  34                 // Handle VT100 (like) escape sequence
  35
  36                 _SysDebug("inc_len = %i, new_bytes = %i", inc_len, new_bytes);
  37
  38                 if( inc_len <= 1 )
  39                         return 1;       // Skip 1 character (the '\x1b')
  40
  41                 switch(inc_buf[1])
  42                 {
  43                 case '[':       // Multibyte, funtime starts
  44                         ret = Term_HandleVT100_Long(inc_len-2, inc_buf+2);
  45                         if( ret > 0 )
  46                                 ret += 2;
  47                         break;
  48                 default:
  49                         ret = 2;
  50                         break;
  51                 }
  52
  53                 if( ret != 0 )
  54                         inc_len = 0;
  55                 return ret;
  56         }
  57
  58         switch( *Buf )
  59         {
  60         case '\b':
  61                 // TODO: Backspace
  62                 Display_MoveCursor(-1, 0);
  63                 return 1;
  64         case '\t':
  65                 // TODO: tab (get current cursor pos, space until multiple of 8)
  66                 return 1;
  67         case '\n':
  68                 Display_Newline(1);
  69                 return 1;
  70         case '\r':
  71                 // TODO: Carriage return
  72                 Display_MoveCursor(INT_MIN, 0);
  73                 return 1;
  74         }
  75
  76          int    ret = 0;
  77         while( ret < Len )
  78         {
  79                 if( *Buf == '\n' )
  80                         break;
  81                 if( *Buf == '\x1b' )
  82                         break;
  83                 ret ++;
  84                 Buf ++;
  85         }
  86         return -ret;
  87 }
  88
  89 int Term_HandleVT100_Long(int Len, const char *Buffer)
  90 {
  91         char    c;
  92          int    argc = 0, j = 0;
  93          int    args[6] = {0,0,0,0,0,0};
  94          int    bQuestionMark = 0;
  95
  96         // Get Arguments
  97         if(j == Len)    return 0;
  98         c = Buffer[j++];
  99         if(c == '?') {
 100                 bQuestionMark = 1;
 101                 if(j == Len)    return 0;
 102                 c = Buffer[j++];
 103         }
 104         if( '0' <= c && c <= '9' )
 105         {
 106                 do {
 107                         if(c == ';') {
 108                                 if(j == Len)    return 0;
 109                                 c = Buffer[j++];
 110                         }
 111                         while('0' <= c && c <= '9') {
 112                                 args[argc] *= 10;
 113                                 args[argc] += c-'0';
 114                                 if(j == Len)    return 0;
 115                                 c = Buffer[j++];
 116                         }
 117                         argc ++;
 118                 } while(c == ';');
 119         }
 120
 121         // Get Command
 122         if( !isalpha(c) ) {
 123                 // Bother.
 124                 _SysDebug("Unexpected char 0x%x in VT100 escape code", c);
 125                 return -1;
 126         }
 127
 128         if( bQuestionMark )
 129         {
 130                 // Special commands
 131                 switch( c )
 132                 {
 133                 default:
 134                         _SysDebug("Unknown VT100 extended escape char 0x%x", c);
 135                         break;
 136                 }
 137         }
 138         else
 139         {
 140                 // Standard commands
 141                 switch( c )
 142                 {
 143                 case 'J':
 144                         if( argc == 0 )
 145                                 Display_ClearLine(0);
 146                         else if( args[0] == 2 )
 147                                 Display_ClearLines(0);  // Entire screen!
 148                         else
 149                                 _SysDebug("TODO: VT100 %i J", args[0]);
 150                         break;
 151                 default:
 152                         _SysDebug("Unknown VT100 escape char 0x%x", c);
 153                         break;
 154                 }
 155         }
 156         return j;
 157 }