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-rw-r--r--src/vga.c262
1 files changed, 0 insertions, 262 deletions
diff --git a/src/vga.c b/src/vga.c
deleted file mode 100644
index 1356d62..0000000
--- a/src/vga.c
+++ /dev/null
@@ -1,262 +0,0 @@
-#include "vga.h"
-
-#include <stdbool.h>
-
-#include "string.h"
-#include "stdlib.h"
-#include "kernel.h"
-
-static bool params_ok( vga_t *vga, const int x, const int y );
-static int calculate_offset( vga_t *vga, const int x, const int y );
-static uint8_t calculate_color_cell( vga_t *vga );
-static void scroll_screen( vga_t *vga );
-
-void vga_init( vga_t *vga )
-{
- memset( vga, 0, sizeof( vga_t ) );
-
- vga->res_x = VGA_DEFAULT_RES_X;
- vga->res_y = VGA_DEFAULT_RES_Y;
- vga->color = VGA_COLOR_DARK_GREY;
- vga->background_color = VGA_COLOR_BLACK;
- vga->show_mouse_cursor = false;
- vga->mouse_cursor_x = -1;
- vga->mouse_cursor_y = -1;
-
- // make sure we use the 0x3dx VGA ports, is done
- // in assembly in stage 2 too
- port8_init( &vga->crtc_misc_port, 0x3d2 );
- port8_write( &vga->crtc_misc_port, 1 );
-
- // set up VGA ports
- port8_init( &vga->crtc_index_port, 0x3d4 );
- port8_init( &vga->crtc_data_port, 0x3d5 );
-
- vga_set_cursor_from_hardware( vga );
-};
-
-void vga_clear_screen( vga_t *vga )
-{
- volatile uint8_t *VIDEO_MEMORY = (uint8_t *)0xb8000;
-
- for( int i = 0; i < 2 * ( vga->res_x * vga->res_y ); i += 2 ) {
- *(VIDEO_MEMORY+i) = ' ';
- *(VIDEO_MEMORY+i+1) = calculate_color_cell( vga );
- }
-
- vga_set_cursor( vga, 0, 0 );
-}
-
-void vga_set_cursor( vga_t *vga, const int x, const int y )
-{
- if( !params_ok( vga, x, y ) ) {
- kernel_panic( "Cursor parameters out of bounds: (%d, %d), resolution is only (%d, %d)",
- x, y, vga->res_x, vga->res_y );
- }
-
- vga->cursor_x = x;
- vga->cursor_y = y;
-
- // TODO: have a silent mode where we don't update the cursor
- vga_set_cursor_on_hardware( vga );
-}
-
-void vga_set_cursor_from_hardware( vga_t *vga )
-{
- uint16_t hw_cursor_pos;
-
- port8_write( &vga->crtc_index_port, 14 );
- uint8_t data = port8_read( &(vga->crtc_data_port ) );
- hw_cursor_pos = data << 8;
-
- port8_write( &vga->crtc_index_port, 15 );
- data = port8_read( &(vga->crtc_data_port ) );
-
- hw_cursor_pos |= data;
-
- vga->cursor_x = hw_cursor_pos % vga->res_x;
- vga->cursor_y = hw_cursor_pos / vga->res_x;
-
- // reset to sane values if we get funny values from the VGA card
- if( vga->cursor_x < 0 || vga->cursor_x > vga->res_x ||
- vga->cursor_y < 0 || vga->cursor_y > vga->res_y ) {
- vga->cursor_x = 0;
- vga->cursor_y = 0;
- }
-}
-
-void vga_set_cursor_on_hardware( vga_t *vga )
-{
- uint16_t hw_cursor_pos = vga->cursor_x + vga->cursor_y * vga->res_x;
-
- port8_write( &vga->crtc_index_port, 15 );
- port8_write( &vga->crtc_data_port, hw_cursor_pos & 0xff );
- port8_write( &vga->crtc_index_port, 14 );
- port8_write( &vga->crtc_data_port, hw_cursor_pos >> 8 );
-}
-
-int vga_get_cursor_x( vga_t *vga )
-{
- return vga->cursor_x;
-}
-
-int vga_get_cursor_y( vga_t *vga )
-{
- return vga->cursor_y;
-}
-
-void vga_set_color( vga_t *vga, const vga_color_t color )
-{
- vga->color = color;
-}
-
-void vga_set_background_color( vga_t *vga, const vga_color_t color )
-{
- vga->background_color = color;
-}
-
-static int calculate_offset( vga_t *vga, const int x, const int y )
-{
- int offset = ( vga->res_x * y + x ) * 2;
-
- return offset;
-}
-
-static void scroll_screen( vga_t *vga )
-{
- volatile uint8_t *VIDEO_MEMORY = (uint8_t *)0xb8000;
-
- memmove( (void *)VIDEO_MEMORY, (const void *)VIDEO_MEMORY + 2 * vga->res_x, 2 * ( vga->res_y - 1 ) * vga->res_x );
-
- for( int i = 2 * ( vga->res_x * ( vga->res_y - 1 ) ); i < 2 * ( vga->res_x * vga->res_y ); i += 2 ) {
- *(VIDEO_MEMORY+i) = ' ';
- *(VIDEO_MEMORY+i+1) = calculate_color_cell( vga );
- }
-
- vga->cursor_y = vga->res_y - 1;
-}
-
-static uint8_t calculate_color_cell( vga_t *vga )
-{
- uint8_t cell;
-
- cell = ( vga->background_color << 4 ) | vga->color;
-
- return cell;
-}
-
-static bool params_ok( vga_t *vga, const int x, const int y )
-{
- if( x > vga->res_x || y > vga->res_y ) return false;
-
- return true;
-}
-
-void vga_put_char_at( vga_t *vga, const int x, const int y, const char c )
-{
- vga_set_cursor( vga, x, y );
- vga_put_char( vga, c );
-}
-
-
-void vga_put_string_at( vga_t *vga, const int x, const int y, const char *s )
-{
- vga_set_cursor( vga, x, y );
- vga_put_string( vga, s );
-}
-
-void vga_put_char( vga_t *vga, const char c )
-{
- int offset = calculate_offset( vga, vga->cursor_x, vga->cursor_y );
-
- volatile uint8_t *VIDEO_MEMORY = (uint8_t *)0xb8000;
- *(VIDEO_MEMORY+offset) = (uint8_t)c;
- *(VIDEO_MEMORY+offset+1) = calculate_color_cell( vga );
-
- vga->cursor_x++;
- if( vga->cursor_x >= vga->res_x ) {
- vga->cursor_x = 0;
- vga->cursor_y++;
- if( vga->cursor_y >= vga->res_y ) {
- scroll_screen( vga );
- }
- }
-
- vga_set_cursor_on_hardware( vga );
-}
-
-void vga_put_string( vga_t *vga, const char *s )
-{
- for( size_t i = 0; i < strlen( s ); i++ ) {
- vga_put_char( vga, s[i] );
- }
-}
-
-void vga_put_newline( vga_t *vga )
-{
- vga->cursor_x = 0;
- vga->cursor_y++;
- if( vga->cursor_y >= vga->res_y ) {
- scroll_screen( vga );
- }
-
- vga_set_cursor_on_hardware( vga );
-}
-
-void vga_set_background_color_at( vga_t *vga, const int x, const int y, vga_color_t color )
-{
- int offset = calculate_offset( vga, x, y );
-
- volatile uint8_t *VIDEO_MEMORY = (uint8_t *)0xb8000;
- *(VIDEO_MEMORY+offset+1) = ( *(VIDEO_MEMORY+offset+1) & 0x0f ) | ( color << 4 );
-}
-
-vga_color_t vga_get_background_color_at( vga_t *vga, const int x, const int y )
-{
- int offset = calculate_offset( vga, x, y );
-
- volatile uint8_t *VIDEO_MEMORY = (uint8_t *)0xb8000;
- uint8_t cell = *(VIDEO_MEMORY+offset+1);
-
- return cell & 0xf0;
-}
-
-void vga_inverse_colors_at( vga_t *vga, const int x, const int y )
-{
- int offset = calculate_offset( vga, x, y );
-
- volatile uint8_t *VIDEO_MEMORY = (uint8_t *)0xb8000;
- *(VIDEO_MEMORY+offset+1) = ( ( *(VIDEO_MEMORY+offset+1) & 0x0f ) << 4 )
- | ( ( *(VIDEO_MEMORY+offset+1) & 0xf0 ) >> 4 );
-}
-
-void vga_show_mouse_cursor( vga_t *vga )
-{
- if( !vga->show_mouse_cursor ) {
- vga->show_mouse_cursor = true;
- vga_inverse_colors_at( vga, vga->mouse_cursor_x, vga->mouse_cursor_y );
- }
-}
-
-void vga_move_mouse_cursor( vga_t *vga, const int x, const int y )
-{
- if( vga->show_mouse_cursor ) {
- vga_inverse_colors_at( vga, vga->mouse_cursor_x, vga->mouse_cursor_y );
- }
-
- vga->mouse_cursor_x = x;
- vga->mouse_cursor_y = y;
-
- if( vga->show_mouse_cursor ) {
- vga_inverse_colors_at( vga, vga->mouse_cursor_x, vga->mouse_cursor_y );
- }
-}
-
-void vga_hide_mouse_cursor( vga_t *vga )
-{
- if( vga->show_mouse_cursor ) {
- vga_inverse_colors_at( vga, vga->mouse_cursor_x, vga->mouse_cursor_y );
- vga->show_mouse_cursor = false;
- }
-}
-
generated by cgit v1.2.3-54-g00ecf (git 2.45.0) at 2024-05-14 23:41:19 +0000