initial commit with a simplified boot eeprom

kitn is intended to be able to boot from the built-in lua bios, but doesn't need e.g. a primary screen/gpu bound

.gitignore

@@ -0,0 +1 @@
+/dist

boot.lua

@@ -0,0 +1,47 @@
+local component, error, select = component, error, select
+local cl, ci, ct = component.list, component.invoke, component.type
+
+local function bail(msg, ...)
+	if select('#', ...) > 0 then
+		msg = msg:format(...)
+	end
+	return error(msg, 0)
+end
+local function unique(addr1, addr2, what)
+	if addr1 and addr2 then
+		return bail('multiple %s: %s, %s', what, addr1, addr2)
+	end
+	return addr1 or addr2 or bail('no %s', what)
+end
+
+local eeprom
+for addr in cl('eeprom') do eeprom = unique(eeprom, addr, 'eeproms') end
+eeprom = unique(eeprom, nil, 'eeprom')
+
+local data = ci(eeprom, 'getData')
+local bootfs
+if data == '' then
+	for fs in cl('filesystem') do
+		if ci(fs, 'exists', '/init.lua') then
+			bootfs = unique(bootfs, fs, 'bootable filesystems')
+		end
+	end
+	bootfs = unique(bootfs, nil, 'bootable filesystem')
+else
+	local ty, err = ct(data)
+	if not ty then bail('bootfs %s absent', data)
+	if ty ~= 'filesystem' then bail('bootfs %s is a %s', data, ty) end
+	bootfs = data
+end
+
+local fd, err = ci(bootfs, 'open', '/init.lua')
+if not fd then bail('open %s/init.lua failed: %s', bootfs:sub(1, 8), err) end
+local code = ''
+repeat
+	local chunk, err = ci(bootfs, 'read', fd, 4096)
+	if err then bail('read %s/init.lua failed: %s', bootfs:sub(1, 8), err) end
+	code = code .. (chunk or '')
+until not chunk
+ci(bootfs, 'close', fd)
+local fn = assert(load(code, '@/init.lua'))
+return fn()