// I have prepared a copy of the appropriate file for blog readers to examine
// without disclosing the name of the programming language. I have also included
// a copy of one of the console drivers which makes use of this interface.
// Enjoy!
use io;
use rt::efi;

// The primary active console device.
export let console: *io::stream = null: *io::stream;

// Sets the active console device.
export fn setcons(cons: *io::stream) void = {
	console = cons;
};

export type syscons = struct {
	name: str,
	cons: *io::stream,
};

def MAX_CONS: size = 16;
let consbuf: [MAX_CONS]syscons = [syscons { cons = null: *io::stream, ... }...];

// List of known consoles. Do not edit.
export let consoles: []syscons = [];

@init fn cons_init() void = {
	consoles = consbuf[..0];
};

// Adds a console to the list of system consoles.
export fn register(name: str, cons: *io::stream) void = {
	if (len(consoles) >= MAX_CONS) {
		return;
	};
	static append(consoles, syscons {
		name = name,
		cons = cons,
	});
};

// Automatically select the best console and set it as the system console.
export fn auto() void = {
	// TODO: Check kernel command line and/or DT /chosen for the user's
	// preference
	if (len(consoles) == 0) {
		return;
	};
	setcons(consoles[0].cons);
};