diff options
Diffstat (limited to 'src/kernel/arch/amd64/tty/vga.c')
-rw-r--r-- | src/kernel/arch/amd64/tty/vga.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/src/kernel/arch/amd64/tty/vga.c b/src/kernel/arch/amd64/tty/vga.c new file mode 100644 index 0000000..e5f2274 --- /dev/null +++ b/src/kernel/arch/amd64/tty/vga.c @@ -0,0 +1,33 @@ +#include <kernel/arch/amd64/tty/tty.h> + +struct vga_cell { + unsigned char c; + unsigned char style; +} __attribute__((__packed__)); + +static const size_t vga_len = 80 * 25; +static struct vga_cell *vga = (void*) 0xB8000; +static size_t vga_pos = 0; + +static void vga_scroll(void) { + for (size_t i = 0; i < vga_len - 80; i++) + vga[i] = vga[i + 80]; + vga_pos -= 80; +} + +static void vga_putchar(char c) { + if (vga_pos >= vga_len - 80) + vga_scroll(); + vga[vga_pos++].c = c; +} + +void vga_write(const char *buf, size_t len) { + for (size_t i = 0; i < len; i++) + vga_putchar(buf[i]); +} + +void vga_clear(void) { + for (size_t i = 0; i < vga_len; i++) + vga[i].c = ' '; + vga_pos = 0; +} |