From 1bf5e324005ce7122a195af106cec656960648dc Mon Sep 17 00:00:00 2001 From: dzwdz Date: Sat, 10 Jul 2021 17:41:32 +0200 Subject: a sensible source structure The idea is that src/kernel/ is only allowed to interface with the hardware using whatever's defined in src/arch/generic.h. I'll probably write a small script for checking this later on. This is a giant commit so I've probably fucked something up. It boots fine on Bochs and QEMU, so at least there's that. --- src/arch/i386/tty.c | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 src/arch/i386/tty.c (limited to 'src/arch/i386/tty.c') diff --git a/src/arch/i386/tty.c b/src/arch/i386/tty.c new file mode 100644 index 0000000..a7c74f5 --- /dev/null +++ b/src/arch/i386/tty.c @@ -0,0 +1,36 @@ +#include + +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 tty_scroll() { + for (int i = 0; i < vga_len - 80; i++) { + vga[i] = vga[i + 80]; + } + vga_pos -= 80; +} + +void tty_putchar(char c) +{ + if (vga_pos >= vga_len - 80) tty_scroll(); + vga[vga_pos++].c = c; +} + +void tty_write(const char *buf, size_t len) +{ + for (size_t i = 0; i < len; i++) { + tty_putchar(buf[i]); + } +} + +void tty_clear() { + for (size_t i = 0; i < vga_len; i++) + vga[i].c = ' '; + vga_pos = 0; +} -- cgit v1.2.3