common: rename decode_short_channel_ids.{c,h} to decode_array.{c.h}

This encoding scheme is no longer just used for short_channel_ids, so make
the names more generic.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

common/decode_array.h

@@ -0,0 +1,47 @@
+#ifndef LIGHTNING_COMMON_DECODE_ARRAY_H
+#define LIGHTNING_COMMON_DECODE_ARRAY_H
+#include "config.h"
+#include <ccan/short_types/short_types.h>
+#include <ccan/tal/tal.h>
+#include <common/bigsize.h>
+
+struct tlv_query_short_channel_ids_tlvs_query_flags;
+
+/* BOLT #7:
+ *
+ * Encoding types:
+ * * `0`: uncompressed array of `short_channel_id` types, in ascending order.
+ * * `1`: array of `short_channel_id` types, in ascending order, compressed with zlib deflate<sup>[1](#reference-1)</sup>
+ */
+enum arr_encode_types {
+	ARR_UNCOMPRESSED = 0,
+	ARR_ZLIB = 1
+};
+
+struct short_channel_id *decode_short_ids(const tal_t *ctx, const u8 *encoded);
+
+/* BOLT #7:
+ *
+ * `encoded_query_flags` is an array of bitfields, one varint per bitfield,
+ * one bitfield for each `short_channel_id`. Bits have the following meaning:
+ *
+ * | Bit Position  | Meaning                                  |
+ * | ------------- | ---------------------------------------- |
+ * | 0             | Sender wants `channel_announcement`      |
+ * | 1             | Sender wants `channel_update` for node 1 |
+ * | 2             | Sender wants `channel_update` for node 2 |
+ * | 3             | Sender wants `node_announcement` for node 1 |
+ * | 4             | Sender wants `node_announcement` for node 2 |
+ */
+enum scid_query_flag {
+	SCID_QF_ANNOUNCE = 0x1,
+	SCID_QF_UPDATE1 = 0x2,
+	SCID_QF_UPDATE2 = 0x4,
+	SCID_QF_NODE1 = 0x8,
+	SCID_QF_NODE2 = 0x10,
+};
+
+bigsize_t *decode_scid_query_flags(const tal_t *ctx,
+				   const struct tlv_query_short_channel_ids_tlvs_query_flags *qf);
+
+#endif /* LIGHTNING_COMMON_DECODE_ARRAY_H */