sys/src/9/pc/cga.c

   1 #include "u.h"
   2 #include "../port/lib.h"
   3 #include "mem.h"
   4 #include "dat.h"
   5 #include "fns.h"
   6 #include "../port/error.h"
   7
   8 enum {
   9         Black,
  10         Blue,
  11         Green,
  12         Cyan,
  13         Red,
  14         Magenta,
  15         Brown,
  16         Grey,
  17
  18         Bright = 0x08,
  19         Blinking = 0x80,
  20
  21         Yellow = Bright|Brown,
  22         White = Bright|Grey,
  23 };
  24
  25 enum {
  26         Width           = 80*2,
  27         Height          = 25,
  28
  29         Attr            = (Black<<4)|Grey,      /* high nibble background
  30                                                  * low foreground
  31                                                  */
  32 };
  33
  34 #define CGASCREENBASE   ((uchar*)KADDR(0xB8000))
  35
  36 static int cgapos;
  37 static Lock cgascreenlock;
  38
  39 static Rune cp437[256] = {
  40         0x2007,0x263A,0x263B,0x2665,0x2666,0x2663,0x2660,0x2022,
  41         0x25D8,0x25CB,0x25D9,0x2642,0x2640,0x266A,0x266B,0x263C,
  42         0x25BA,0x25C4,0x2195,0x203C,0x00B6,0x00A7,0x25AC,0x21A8,
  43         0x2191,0x2193,0x2192,0x2190,0x221F,0x2194,0x25B2,0x25BC,
  44         0x0020,0x0021,0x0022,0x0023,0x0024,0x0025,0x0026,0x0027,
  45         0x0028,0x0029,0x002A,0x002B,0x002C,0x002D,0x002E,0x002F,
  46         0x0030,0x0031,0x0032,0x0033,0x0034,0x0035,0x0036,0x0037,
  47         0x0038,0x0039,0x003A,0x003B,0x003C,0x003D,0x003E,0x003F,
  48         0x0040,0x0041,0x0042,0x0043,0x0044,0x0045,0x0046,0x0047,
  49         0x0048,0x0049,0x004A,0x004B,0x004C,0x004D,0x004E,0x004F,
  50         0x0050,0x0051,0x0052,0x0053,0x0054,0x0055,0x0056,0x0057,
  51         0x0058,0x0059,0x005A,0x005B,0x005C,0x005D,0x005E,0x005F,
  52         0x0060,0x0061,0x0062,0x0063,0x0064,0x0065,0x0066,0x0067,
  53         0x0068,0x0069,0x006A,0x006B,0x006C,0x006D,0x006E,0x006F,
  54         0x0070,0x0071,0x0072,0x0073,0x0074,0x0075,0x0076,0x0077,
  55         0x0078,0x0079,0x007A,0x007B,0x007C,0x007D,0x007E,0x2302,
  56         0x00C7,0x00FC,0x00E9,0x00E2,0x00E4,0x00E0,0x00E5,0x00E7,
  57         0x00EA,0x00EB,0x00E8,0x00EF,0x00EE,0x00EC,0x00C4,0x00C5,
  58         0x00C9,0x00E6,0x00C6,0x00F4,0x00F6,0x00F2,0x00FB,0x00F9,
  59         0x00FF,0x00D6,0x00DC,0x00A2,0x00A3,0x00A5,0x20A7,0x0192,
  60         0x00E1,0x00ED,0x00F3,0x00FA,0x00F1,0x00D1,0x00AA,0x00BA,
  61         0x00BF,0x2310,0x00AC,0x00BD,0x00BC,0x00A1,0x00AB,0x00BB,
  62         0x2591,0x2592,0x2593,0x2502,0x2524,0x2561,0x2562,0x2556,
  63         0x2555,0x2563,0x2551,0x2557,0x255D,0x255C,0x255B,0x2510,
  64         0x2514,0x2534,0x252C,0x251C,0x2500,0x253C,0x255E,0x255F,
  65         0x255A,0x2554,0x2569,0x2566,0x2560,0x2550,0x256C,0x2567,
  66         0x2568,0x2564,0x2565,0x2559,0x2558,0x2552,0x2553,0x256B,
  67         0x256A,0x2518,0x250C,0x2588,0x2584,0x258C,0x2590,0x2580,
  68         0x03B1,0x00DF,0x0393,0x03C0,0x03A3,0x03C3,0x00B5,0x03C4,
  69         0x03A6,0x0398,0x03A9,0x03B4,0x221E,0x03C6,0x03B5,0x2229,
  70         0x2261,0x00B1,0x2265,0x2264,0x2320,0x2321,0x00F7,0x2248,
  71         0x00B0,0x2219,0x00B7,0x221A,0x207F,0x00B2,0x25A0,0x00A0,
  72 };
  73
  74 static uchar
  75 cgaregr(int index)
  76 {
  77         outb(0x3D4, index);
  78         return inb(0x3D4+1) & 0xFF;
  79 }
  80
  81 static void
  82 cgaregw(int index, int data)
  83 {
  84         outb(0x3D4, index);
  85         outb(0x3D4+1, data);
  86 }
  87
  88 static void
  89 movecursor(void)
  90 {
  91         cgaregw(0x0E, (cgapos/2>>8) & 0xFF);
  92         cgaregw(0x0F, cgapos/2 & 0xFF);
  93         CGASCREENBASE[cgapos+1] = Attr;
  94 }
  95
  96 static void
  97 cgascreenputc(Rune c)
  98 {
  99         int i;
 100         uchar *p;
 101
 102         if(c == '\0')
 103                 return;
 104         else if(c == '\n'){
 105                 cgapos = cgapos/Width;
 106                 cgapos = (cgapos+1)*Width;
 107         }
 108         else if(c == '\t'){
 109                 i = 8 - ((cgapos/2)&7);
 110                 while(i-->0)
 111                         cgascreenputc(' ');
 112         }
 113         else if(c == '\b'){
 114                 if(cgapos >= 2)
 115                         cgapos -= 2;
 116                 cgascreenputc(' ');
 117                 cgapos -= 2;
 118         }
 119         else{
 120                 for(i=0; i<nelem(cp437); i++)
 121                         if(cp437[i] == c)
 122                                 break;
 123                 if(i == nelem(cp437))
 124                         i = 0xfe; /* peter */
 125                 CGASCREENBASE[cgapos++] = i;
 126                 CGASCREENBASE[cgapos++] = Attr;
 127         }
 128         if(cgapos >= Width*Height){
 129                 memmove(CGASCREENBASE, &CGASCREENBASE[Width], Width*(Height-1));
 130                 p = &CGASCREENBASE[Width*(Height-1)];
 131                 for(i=0; i<Width/2; i++){
 132                         *p++ = ' ';
 133                         *p++ = Attr;
 134                 }
 135                 cgapos = Width*(Height-1);
 136         }
 137         movecursor();
 138 }
 139
 140 static void
 141 cgascreenputs(char* s, int n)
 142 {
 143         static char rb[UTFmax];
 144         static int nrb;
 145         char *e;
 146         Rune r;
 147
 148         if(!islo()){
 149                 /*
 150                  * Don't deadlock trying to
 151                  * print in an interrupt.
 152                  */
 153                 if(!canlock(&cgascreenlock))
 154                         return;
 155         }
 156         else
 157                 lock(&cgascreenlock);
 158
 159         e = s + n;
 160         while(s < e){
 161                 rb[nrb++] = *s++;
 162                 if(nrb >= UTFmax || fullrune(rb, nrb)){
 163                         chartorune(&r, rb);
 164                         cgascreenputc(r);
 165                         nrb = 0;
 166                 }
 167         }
 168
 169         unlock(&cgascreenlock);
 170 }
 171
 172 static void
 173 cgatokmesg(void)
 174 {
 175         int i, n;
 176         char *p;
 177
 178         ilock(&kmesg.lk);
 179         n = kmesg.n;
 180         for(i = cgapos-2; i >= 0 && n < sizeof kmesg.buf-UTFmax-1; i -= 2){
 181                 if((i % Width) == Width-2)
 182                         n++;
 183                 n += runelen(cp437[CGASCREENBASE[i]]);
 184         }
 185         n -= kmesg.n;
 186         if(n > 0){
 187                 memmove(kmesg.buf+n, kmesg.buf, kmesg.n);
 188                 kmesg.n += n;
 189                 p = kmesg.buf;
 190                 for(i += 2; i >= 0 && i < cgapos && p < kmesg.buf+n; i += 2){
 191                         p += runetochar(p, &cp437[CGASCREENBASE[i]]);
 192                         if((i % Width) == Width-2)
 193                                 *p++ = '\n';
 194                 }
 195         }
 196         iunlock(&kmesg.lk);
 197 }
 198
 199 void
 200 screeninit(void)
 201 {
 202         static int once;
 203
 204         cgapos = cgaregr(0x0E)<<8;
 205         cgapos |= cgaregr(0x0F);
 206         cgapos *= 2;
 207
 208         if(cgapos >= Width*Height){
 209                 cgapos = 0;
 210                 movecursor();
 211         }
 212
 213         if(once == 0){
 214                 once = 1;
 215                 cgatokmesg();
 216         }
 217
 218         screenputs = cgascreenputs;
 219 }