kernel/arch/x86/tty/tty.c

   1 #include <io.h>
   2 #include <tty.h>
   3 #include <stdint.h>
   4 #include <input/ps2.h>
   5
   6 #define VGA_WIDTH 80
   7 #define VGA_HEIGHT 25
   8
   9 volatile char *video_memory = (char *) 0xB8000; /* VGA VRAM starts at 0xB8000 */
  10
  11 static int cursor_x = 0; /* keep track of where cursor is */
  12 static int cursor_y = 0;
  13
  14 char *hex_chars = "0123456789ABCDEF";
  15 char kgets_buffer[100];
  16
  17 void screen_clear(void)
  18 {
  19         int x, y;
  20         for ( y = 0; y < VGA_HEIGHT; y++ ) {
  21                 for ( x = 0; x < VGA_WIDTH; x++ ) {
  22                         video_memory[(y * VGA_WIDTH + x) * 2 + 1] = VGA_COLOR_LIGHT_GRAY;
  23                         video_memory[(y * VGA_WIDTH + x) * 2] = ' ';
  24                 }
  25         }
  26
  27         cursor_x = 0;
  28         cursor_y = 0;
  29 }
  30
  31 void scroll_up(void)
  32 {
  33         int x, y;
  34         for ( y = 1; y < VGA_HEIGHT; y++ ) {
  35                 for ( x = 0; x < VGA_WIDTH; x++ ) {
  36                         video_memory[((y - 1) * VGA_WIDTH + x) * 2] = video_memory[(y * VGA_WIDTH + x) * 2];
  37                 }
  38         }
  39         for ( x = 0; x < VGA_WIDTH; x++ ) {
  40                 video_memory[((VGA_HEIGHT - 1) * VGA_WIDTH + x) * 2] = ' ';
  41         }
  42         cursor_y = VGA_HEIGHT - 1;
  43 }
  44
  45 void kprint(const char *string, uint8_t color)
  46 {
  47         char next_char;
  48         uint8_t vga_misc_output;
  49         uint16_t crtc_port;
  50         next_char = *string;
  51
  52         while ( next_char != 0 ) {
  53                 if ( next_char == '\n') { cursor_x = 0; cursor_y++; }
  54                 else { video_memory[(cursor_y * VGA_WIDTH + cursor_x) * 2] = next_char; video_memory[((cursor_y * VGA_WIDTH + cursor_x++) * 2)+ 1] = color != 0 ? color : VGA_COLOR_LIGHT_GRAY; }
  55                 if ( cursor_x >= VGA_WIDTH ) { cursor_x = 0; cursor_y++; }
  56                 if ( cursor_y >= VGA_HEIGHT ) { scroll_up(); }
  57                 next_char = *++string;
  58         }
  59
  60         vga_misc_output = inb(0x3CC);
  61         if (vga_misc_output & 0x1 == 0) {
  62                 crtc_port = 0x3B4;
  63         } else {
  64                 crtc_port = 0x3D4;
  65         }
  66
  67         outb(crtc_port, 0xE);
  68         outb(crtc_port + 1, (cursor_y * VGA_WIDTH + cursor_x) >> 8);
  69         outb(crtc_port, 0xF);
  70         outb(crtc_port + 1, (cursor_y * VGA_WIDTH + cursor_x) & 0xFF);
  71 }
  72
  73 void kprintc(const char character, uint8_t color)
  74 {
  75         uint8_t vga_misc_output;
  76         uint16_t crtc_port;
  77
  78         if ( character == '\n') { cursor_x = 0; cursor_y++; }
  79         if (character == 0x7f) {
  80                 cursor_x--;
  81                 if (cursor_x < 0) {
  82                         if (cursor_y > 0) {
  83                                 cursor_x = VGA_WIDTH - 1;
  84                                 cursor_y--;
  85                         } else cursor_x = 0;
  86                 }
  87                 video_memory[(cursor_y * VGA_WIDTH + cursor_x) * 2] = ' ';
  88         }
  89         else { video_memory[(cursor_y * VGA_WIDTH + cursor_x) * 2] = character; video_memory[((cursor_y * VGA_WIDTH + cursor_x++) * 2)+ 1] = color != 0 ? color : VGA_COLOR_LIGHT_GRAY; }
  90         if ( cursor_x >= VGA_WIDTH ) { cursor_x = 0; cursor_y++; }
  91         if ( cursor_y >= VGA_HEIGHT ) { scroll_up(); }
  92
  93         vga_misc_output = inb(0x3CC);
  94         if (vga_misc_output & 0x1 == 0) {
  95                 crtc_port = 0x3B4;
  96         } else {
  97                 crtc_port = 0x3D4;
  98         }
  99
 100         outb(crtc_port, 0xE);
 101         outb(crtc_port + 1, (cursor_y * VGA_WIDTH + cursor_x) >> 8);
 102         outb(crtc_port, 0xF);
 103         outb(crtc_port + 1, (cursor_y * VGA_WIDTH + cursor_x) & 0xFF);
 104
 105 }
 106
 107 void kprintb(uint8_t byte)
 108 {
 109         uint8_t temp;
 110         temp = byte >> 4;
 111         kprint("0x", VGA_COLOR_LIGHT_GRAY);
 112         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 113         temp = byte & 0xF;
 114         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 115 }
 116
 117 void kprintw(uint16_t word)
 118 {
 119         uint8_t temp;
 120         temp = word >> 12;
 121         kprint("0x", VGA_COLOR_LIGHT_GRAY);
 122         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 123         temp = (word >> 8) & 0xF;
 124         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 125         temp = (word >> 4) & 0xF;
 126         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 127         temp = word & 0xF;
 128         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 129 }
 130
 131 void kprintd(uint32_t dword)
 132 {
 133         uint8_t temp;
 134         temp = dword >> 28;
 135         kprint("0x", VGA_COLOR_LIGHT_GRAY);
 136         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 137         temp = (dword >> 24) & 0xF;
 138         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 139         temp = (dword >> 20) & 0xF;
 140         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 141         temp = (dword >> 16) & 0xF;
 142         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 143         temp = (dword >> 12) & 0xF;
 144         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 145         temp = (dword >> 8) & 0xF;
 146         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 147         temp = (dword >> 4) & 0xF;
 148         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 149         temp = dword & 0xF;
 150         kprintc(hex_chars[temp], VGA_COLOR_LIGHT_GRAY);
 151 }
 152
 153 char *kgets()
 154 {
 155         for (int i=0; i<100; i++) {
 156                 kgets_buffer[i] = '\0';
 157         }
 158
 159         int i=0;
 160         while (i<100) {
 161                 char temp = ps2_get_keystroke();
 162                 if (temp == '\n') break;
 163                 if (temp == 0x7f) {
 164                         if (i>0) {
 165                                 i-=1;
 166                                 kgets_buffer[i] = '\0';
 167                                 kprintc(temp, 0);
 168                         }
 169                         continue;
 170                 }
 171                 kgets_buffer[i] = temp;
 172                 kprintc(temp, 0);
 173                 i++;
 174         }
 175
 176         return kgets_buffer;
 177 }