diff --git a/drivers/tty.c b/drivers/tty.c new file mode 100644 index 0000000..ae31c1e --- /dev/null +++ b/drivers/tty.c @@ -0,0 +1,179 @@ +#include +#include +#include + +#include +#include +#include +#include + +static size_t terminal_row; +static size_t terminal_column; +static uint8_t terminal_color; +static uint16_t* terminal_buffer; + +void terminal_initialize(void) +{ + terminal_initializec(0x00); +} + +void terminal_initializec(uint8_t color) +{ + terminal_row = 0; + terminal_column = 0; + + if (color == 0x00) + { + terminal_color = vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK); + } + else { + terminal_color = color; + } + + terminal_buffer = VGA_MEMORY; + for (size_t y = 0; y < VGA_HEIGHT; y++) + { + for (size_t x = 0; x < VGA_WIDTH; x++) + { + const size_t index = y * VGA_WIDTH + x; + terminal_buffer[index] = vga_entry(' ', terminal_color); + } + } +} + +void terminal_setcolor(uint8_t color) +{ + terminal_color = color; +} + +uint8_t terminal_getcolor(void) +{ + return terminal_color; +} + +void terminal_putentryat(unsigned char c, uint8_t color, size_t x, size_t y) +{ + const size_t index = y * VGA_WIDTH + x; + terminal_buffer[index] = vga_entry(c, color); +} + +void terminal_putchar(const char c) +{ + unsigned char uc = c; + + if (uc == '\n') + { + terminal_column = 0; + if (++terminal_row == VGA_HEIGHT) + { + terminal_scroll(); + terminal_row = VGA_HEIGHT - 1; + } + return; + } + else if (uc == '\t') + { + terminal_column += 4; + + if (terminal_column >= VGA_WIDTH) + { + terminal_putchar('\n'); + } + + return; + } + + terminal_putentryat(uc, terminal_color, terminal_column, terminal_row); + + + if (++terminal_column == VGA_WIDTH) + { + terminal_column = 0; + if (++terminal_row == VGA_HEIGHT) + { + terminal_scroll(); + terminal_row = VGA_HEIGHT - 1; + } + } +} + +void terminal_write(const char* data, size_t size) +{ + for (size_t i = 0; i < size; i++) + { + terminal_putchar(data[i]); + } +} + +void terminal_writestring(const char* data) +{ + terminal_write(data, strlen(data)); +} + +void terminal_debug_writestring(const char* data) +{ + terminal_writestring("[ DEBUG ] "); + terminal_writestring(data); +} + +void terminal_writeline(const char* data) +{ + terminal_column = 0; + terminal_writestring(data); +} + +void terminal_writechar_r(const char ch) +{ + unsigned char uch = ch; + + for (size_t i = 0; i < VGA_WIDTH; i++) + { + terminal_putchar(uch); + } +} + +void terminal_clear(void) +{ + terminal_clearl(-1); +} + +void terminal_clearl(size_t num_lines) +{ + if (num_lines == (size_t)-1) + { + terminal_initializec(terminal_getcolor()); + } + else + { + /* XXX note to self: VGA_HEIGHT is 25, and VGA_WIDTH is 80 XXX */ + /* static size_t terminal_row; static size_t terminal_column; */ + + terminal_row = VGA_HEIGHT; + terminal_column = 0; + + while (terminal_row < num_lines) + { + terminal_writechar_r(' '); + terminal_row -= 1; + } + } +} + +void terminal_scroll(void) +{ + for (size_t y = 1; y < VGA_HEIGHT; y++) + { + for (size_t x = 0; x < VGA_WIDTH; x++) + { + const size_t src_index = y * VGA_WIDTH + x; + const size_t dst_index = (y - 1) * VGA_WIDTH + x; + terminal_buffer[dst_index] = terminal_buffer[src_index]; + } + } + + for (size_t x = 0; x < VGA_WIDTH; x++) + { + const size_t index = (VGA_HEIGHT - 1) * VGA_WIDTH + x; + terminal_buffer[index] = (terminal_color << 8) | ' '; + } +}