cethcan: beancounters support

1 files changed, 91 insertions, 0 deletions

diff --git a/cethcan/beanctr.c b/cethcan/beanctr.c
new file mode 100644
index 0000000..d381c79
--- /dev/null
+++ b/cethcan/beanctr.c
@@ -0,0 +1,91 @@
+#include "cethcan.h"
+
+struct bean {
+	struct can_user *u;
+
+	char *name;
+	unsigned logical_addr;
+
+	uint8_t raw;
+	json_t *vals[2];
+
+	time_t change, valid;
+};
+
+static void bean_json_handler(void *arg, json_t *json, enum json_subtype type)
+{
+	struct bean *b = arg;
+	json_t *bobj = json_object();
+
+	json_object_set_new(bobj, "klass", json_string("beancounter"));
+	json_object_set_new(bobj, "addr", json_integer(b->logical_addr));
+
+	json_object_set_new(bobj, "raw", json_integer(b->raw));
+	json_object_set_new(bobj, "value", json_boolean(b->raw & 1));
+	json_object_set_new(bobj, "text", json_incref(b->vals[b->raw & 1]));
+	if (type != JSON_LONGPOLL)
+		json_object_set_new(bobj, "ts", json_integer(b->valid));
+	json_object_set_new(bobj, "tschg", json_integer(b->change));
+
+	json_object_set_new(json, b->name, bobj);
+}
+
+static void bean_can_handler(void *arg, struct can_message *msg)
+{
+	struct bean *b = arg;
+	unsigned laddr;
+	uint8_t dval;
+
+	if ((msg->daddr & CANA_PROTOCOL) != CANA_SENSOR)
+		return;
+
+	laddr = msg->daddr & 0xfff;
+	if (b->logical_addr < laddr)
+		return;
+	if (b->logical_addr - laddr >= msg->dlc)
+		return;
+	dval = msg->bytes[b->logical_addr - laddr];
+
+	time(&b->valid);
+	if (dval != b->raw || b->change == 0) {
+		b->raw = dval;
+		time(&b->change);
+		lprintf("%s: set %02x", b->u->name, dval);
+
+		json_bump_longpoll();
+	}
+}
+
+int bean_init_conf(json_t *config)
+{
+	struct bean *b;
+	json_t *vals;
+
+	if (!json_is_object(config)) {
+		lprintf("light config must be an object/dictionary");
+		return 1;
+	}
+	if (!json_is_integer(json_object_get(config, "addr"))) {
+		lprintf("light config must have an 'addr' key");
+		return 1;
+	}
+	if (!json_is_string(json_object_get(config, "name"))) {
+		lprintf("light config must have a 'name' key");
+		return 1;
+	}
+	vals = json_object_get(config, "values");
+	if (!json_is_array(vals) || json_array_size(vals) != 2) {
+		lprintf("light config must have a 'values' array of len 2");
+		return 1;
+	}
+
+	b = calloc(sizeof(*b), 1);
+	b->name = strdup(json_string_value(json_object_get(config, "name")));
+	b->logical_addr = json_integer_value(json_object_get(config, "addr"));
+	b->vals[0] = json_array_get(vals, 0);
+	b->vals[1] = json_array_get(vals, 1);
+
+	b->u = can_register_alloc(b, bean_can_handler, "bean[%s]", b->name);
+	b->u->json = bean_json_handler;
+	return 0;
+}