commands/loadfont/loadfont.c

   1 /* loadfont.c - Load custom font into EGA, VGA video card
   2  *
   3  * Author: Hrvoje Stipetic (hs@hck.hr) Jun-1995.
   4  *
   5  */
   6
   7 #include <sys/types.h>
   8 #include <fcntl.h>
   9 #include <unistd.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <errno.h>
  13 #include <termios.h>
  14 #include <sys/ioctl.h>
  15
  16 void tell(char *s)
  17 {
  18   write(2, s, strlen(s));
  19 }
  20
  21 char *itoa(unsigned i)
  22 {
  23   static char a[3*sizeof(int)];
  24   char *p = a+sizeof(a)-1;
  25
  26   do {
  27         *--p = '0' + i%10;
  28   } while ((i /= 10) > 0);
  29
  30   return p;
  31 }
  32
  33 void report(char *say)
  34 {
  35   int err = errno;
  36   tell("loadfont: ");
  37   if (say != NULL) {
  38         tell(say);
  39         tell(": ");
  40   }
  41   tell(strerror(err));
  42   tell("\n");
  43 }
  44
  45 void usage(void)
  46 {
  47   tell("Usage: loadfont fontfile\n");
  48   exit(1);
  49 }
  50
  51
  52 int main(int argc, char *argv[])
  53 {
  54   static u8_t font[256][32];
  55   static u8_t font_file[256 * (16+14+8) + 1];
  56   u8_t *ff;
  57   int fd, size, tsize, ch, ln;
  58   struct winsize ws;
  59
  60
  61   if (argc != 2)
  62         usage();
  63
  64   if ((fd = open(argv[1], O_RDONLY)) < 0) {
  65         report(argv[1]);
  66         exit(1);
  67   }
  68
  69   switch (read(fd, font_file, sizeof(font_file))) {
  70   case 256 * 8:
  71         size = 8;
  72         break;
  73   case 256 * 14:
  74         size = 14;
  75         break;
  76   case 256 * 16:
  77         size = 16;
  78         break;
  79   case 256 * (16+14+8):
  80         size = 0;
  81         break;
  82   case -1:
  83         report(argv[1]);
  84         exit(1);
  85   default:
  86         tell("loadfont: ");
  87         tell(argv[1]);
  88         tell(": fontfile is not an 8x8, 8x14, 8x16, or compound font\n");
  89         exit(1);
  90   }
  91   close(fd);
  92
  93   if (ioctl(0, TIOCGWINSZ, &ws) < 0 || (errno= ENOTTY, ws.ws_row == 0)) {
  94         report(NULL);
  95         exit(1);
  96   }
  97   tsize = ws.ws_ypixel / ws.ws_row;
  98
  99   if (size == 0) {
 100         if (tsize >= 16) {
 101                 ff = font_file + 256 * (0);
 102         } else
 103         if (tsize >= 14) {
 104                 ff = font_file + 256 * (16);
 105         } else {
 106                 ff = font_file + 256 * (16 + 14);
 107         }
 108         size = tsize;
 109   } else {
 110         ff = font_file;
 111   }
 112
 113   for (ch = 0; ch < 256; ch++) {
 114         for (ln = 0; ln < size; ln++) font[ch][ln] = ff[ch * size + ln];
 115   }
 116
 117   if (ioctl(0, TIOCSFON, font) < 0) {
 118         report(NULL);
 119         exit(1);
 120   }
 121   exit(0);
 122 }