lightningd/chaintopology: free block map and watches on exit.

Direct leak of 64 byte(s) in 1 object(s) allocated from:
    #0 0x7f4dc279163e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10c63e)
    #1 0x564ee8a24bb1 in htable_default_alloc ccan/ccan/htable/htable.c:19
    #2 0x564ee8a2551b in double_table ccan/ccan/htable/htable.c:226
    #3 0x564ee8a259e5 in htable_add_ ccan/ccan/htable/htable.c:331
    #4 0x564ee89a5300 in block_map_add lightningd/chaintopology.h:83
    #5 0x564ee89a6ece in add_tip lightningd/chaintopology.c:626
    #6 0x564ee89a72c3 in have_new_block lightningd/chaintopology.c:694
    #7 0x564ee89a3ab0 in process_rawblock lightningd/bitcoind.c:466
    #8 0x564ee89a2fb4 in bcli_finished lightningd/bitcoind.c:214
    #9 0x564ee8a284d6 in destroy_conn ccan/ccan/io/poll.c:244
    #10 0x564ee8a284f6 in destroy_conn_close_fd ccan/ccan/io/poll.c:250
    #11 0x564ee8a34a0d in notify ccan/ccan/tal/tal.c:235
    #12 0x564ee8a34efc in del_tree ccan/ccan/tal/tal.c:397
    #13 0x564ee8a35288 in tal_free ccan/ccan/tal/tal.c:481
    #14 0x564ee8a26cf5 in io_close ccan/ccan/io/io.c:450
    ElementsProject#15 0x564ee8a28c11 in io_loop ccan/ccan/io/poll.c:449
    ElementsProject#16 0x564ee89b3c3b in io_loop_with_timers lightningd/io_loop_with_timers.c:24
    ElementsProject#17 0x564ee89ba540 in main lightningd/lightningd.c:822
    ElementsProject#18 0x7f4dc2143b6a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x26b6a)

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

lightningd/chaintopology.c

@@ -855,6 +855,11 @@ static void destroy_chain_topology(struct chain_topology *topo)
 
 	while ((otx = list_pop(&topo->outgoing_txs, struct outgoing_tx, list)))
 		tal_free(otx);
+
+	/* htable uses malloc, so it would leak here */
+	txwatch_hash_clear(&topo->txwatches);
+	txowatch_hash_clear(&topo->txowatches);
+	block_map_clear(&topo->block_map);
 }
 
 struct chain_topology *new_topology(struct lightningd *ld, struct log *log)