47 lines
927 B
C
47 lines
927 B
C
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#include "screen.h"
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#include "../kernel/ports.h"
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void print_char(char c, int col, int row, char attr_byte) {
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unsigned char *vidmem = (unsigned char*) VIDEO_ADDRESS;
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if(!attr_byte)
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attr_byte = WHITE_ON_BLACK;
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/* get the offset of the screen location specified */
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int offset;
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/*
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* if row & col are non-negative then they can be used
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* as an offset
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*/
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if(col >= 0 && row >= 0)
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{
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offset = get_screen_offset(col, row);
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}
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/* otherwise use the cursor's current location */
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else
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{
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offset = get_cursor();
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}
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/* handle a newline */
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if(c == '\n')
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{
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int rows = offset / (2 * MAX_COLS);
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offset = get_screen_offset(79,rows);
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}
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/* else set the character */
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else
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{
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vidmem[offset] = c;
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vidmem[offset+1] = attr_byte;
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}
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/* update the offset to the next cell */
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offset += 2;
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/* set scrolling adjustment */
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offset = handle_scrolling(offset);
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/* update the cursor position */
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set_cursor(offset);
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}
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