get-anchor-depth: simple helper to get min_confirms from OpenChannel packet

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

Makefile

@@ -3,7 +3,7 @@
 # Needs to have oneof support: Ubuntu vivid's is too old :(
 PROTOCC:=protoc-c
 
-PROGRAMS := open-channel open-anchor-scriptsigs leak-anchor-sigs open-commit-sig check-commit-sig check-anchor-scriptsigs
+PROGRAMS := open-channel open-anchor-scriptsigs leak-anchor-sigs open-commit-sig check-commit-sig check-anchor-scriptsigs get-anchor-depth
 
 HELPER_OBJS := base58.o lightning.pb-c.o shadouble.o pkt.o bitcoin_script.o permute_tx.o signature.o bitcoin_tx.o bitcoin_address.o anchor.o commit_tx.o pubkey.o
 

get-anchor-depth.c

@@ -0,0 +1,47 @@
+/* My example:
+ * while [ 0$(bitcoin-cli -testnet getrawtransaction $(cat anchor.txid) 1 | sed -n 's/.*"confirmations" : \([0-9]*\),/\1/p') -lt $(./get-anchor-depth A-open.pb) ]; do sleep 60; done
+ * while [ 0$(bitcoin-cli -testnet getrawtransaction $(cat anchor.txid) 1 | sed -n 's/.*"confirmations" : \([0-9]*\),/\1/p') -lt $(./get-anchor-depth B-open.pb) ]; do sleep 60; done
+ */
+#include <ccan/crypto/shachain/shachain.h>
+#include <ccan/short_types/short_types.h>
+#include <ccan/tal/tal.h>
+#include <ccan/opt/opt.h>
+#include <ccan/str/hex/hex.h>
+#include <ccan/err/err.h>
+#include <ccan/read_write_all/read_write_all.h>
+#include "lightning.pb-c.h"
+#include "anchor.h"
+#include "base58.h"
+#include "pkt.h"
+#include "bitcoin_script.h"
+#include "permute_tx.h"
+#include "signature.h"
+#include "commit_tx.h"
+#include "pubkey.h"
+#include <openssl/ec.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[])
+{
+	const tal_t *ctx = tal_arr(NULL, char, 0);
+	OpenChannel *o;
+
+	err_set_progname(argv[0]);
+
+	opt_register_noarg("--help|-h", opt_usage_and_exit,
+			   "<open-channel-file>\n"
+			   "Prints anchor depth as contained in OpenChannel message",
+			   "Print this message.");
+
+ 	opt_parse(&argc, argv, opt_log_stderr_exit);
+
+	if (argc != 2)
+		opt_usage_exit_fail("Expected one argument");
+
+	o = pkt_from_file(argv[1], PKT__PKT_OPEN)->open;
+	printf("%u\n", o->anchor->min_confirms);
+
+	tal_free(ctx);
+	return 0;
+}
+