term: add term.ui module (part 2) (#6798)

vlib/term/ui/input_nix.c.v

@@ -0,0 +1,86 @@
+module ui
+
+const (
+	ctx_ptr = &Context(0)
+)
+
+pub fn init(cfg Config) &Context {
+	mut ctx := &Context{
+		cfg: cfg,
+		read_buf: []byte{ cap: cfg.buffer_size }
+	}
+
+	if cfg.hide_cursor {
+		s := '\x1b[?25l'
+		C.write(C.STDOUT_FILENO, s.str, s.len)
+	}
+
+	unsafe {
+		x := &ctx_ptr
+		*x = ctx
+	}
+
+	return ctx
+}
+
+pub fn (mut ctx Context) run() {
+	if ctx.cfg.use_x11 {
+		ctx.fail('error: x11 backend not implemented yet')
+		exit(1)
+	} else {
+		ctx.termios_setup()
+		ctx.termios_loop()
+	}
+}
+
+[inline]
+// shifts the array left, to remove any data that was just read, and updates its len
+// TODO: remove
+fn (mut ctx Context) shift(len int) {
+	unsafe {
+		C.memmove(ctx.read_buf.data, ctx.read_buf.data + len, ctx.read_buf.cap - len)
+		ctx.resize_arr(ctx.read_buf.len - len)
+	}
+}
+
+// TODO: don't actually do this, lmao
+[inline]
+fn (mut ctx Context) resize_arr(size int) {
+	mut l := &ctx.read_buf.len
+	unsafe { *l = size }
+}
+
+[inline]
+fn (ctx &Context) init() {
+	if ctx.cfg.init_fn != voidptr(0) {
+		ctx.cfg.init_fn(ctx.cfg.user_data)
+	}
+}
+
+[inline]
+fn (ctx &Context) frame() {
+	if ctx.cfg.frame_fn != voidptr(0) {
+		ctx.cfg.frame_fn(ctx.cfg.user_data)
+	}
+}
+
+[inline]
+fn (ctx &Context) cleanup() {
+	if ctx.cfg.cleanup_fn != voidptr(0) {
+		ctx.cfg.cleanup_fn(ctx.cfg.user_data)
+	}
+}
+
+[inline]
+fn (ctx &Context) fail(error string) {
+	if ctx.cfg.fail_fn != voidptr(0) {
+		ctx.cfg.fail_fn(error)
+	}
+}
+
+[inline]
+fn (ctx &Context) event(event &Event) {
+	if ctx.cfg.event_fn != voidptr(0) {
+		ctx.cfg.event_fn(event, ctx.cfg.user_data)
+	}
+}