locktime: nice abstractions for absolute and relative locktimes.

I got confused navigating these, especially since Alpha and Bitcoin
have diverged (BIP68 was proposed after Elements Alpha).

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

test-cli/create-commit-spend-tx.c

@@ -21,6 +21,7 @@
 #include "test-cli/gather_updates.h"
 #include "funding.h"
 #include "version.h"
+#include "bitcoin/locktime.h"
 #include <unistd.h>
 
 int main(int argc, char *argv[])
@@ -37,7 +38,7 @@ int main(int argc, char *argv[])
 	struct sha256 rhash;
 	size_t p2sh_out;
 	u64 fee = 10000;
-	u32 locktime;
+	struct rel_locktime locktime;
 
 	err_set_progname(argv[0]);
 
@@ -87,7 +88,7 @@ int main(int argc, char *argv[])
 		       NULL, &rhash, NULL, NULL);
 
 	/* Create redeem script */
-	redeemscript = bitcoin_redeem_secret_or_delay(ctx, &pubkey1, locktime,
+	redeemscript = bitcoin_redeem_secret_or_delay(ctx, &pubkey1, &locktime,
 						      &pubkey2, &rhash);
 
 	/* Now, create transaction to spend it. */
@@ -98,7 +99,7 @@ int main(int argc, char *argv[])
 	tx->input[0].input_amount = commit->output[p2sh_out].amount;
 	tx->fee = fee;
 
-	tx->input[0].sequence_number = bitcoin_nsequence(locktime);
+	tx->input[0].sequence_number = bitcoin_nsequence(&locktime);
 
 	if (commit->output[p2sh_out].amount <= fee)
 		errx(1, "Amount of %llu won't exceed fee",

test-cli/create-htlc-spend-tx.c

@@ -16,6 +16,7 @@
 #include "bitcoin/privkey.h"
 #include "protobuf_convert.h"
 #include "find_p2sh_out.h"
+#include "bitcoin/locktime.h"
 #include "version.h"
 #include <unistd.h>
 
@@ -31,7 +32,8 @@ int main(int argc, char *argv[])
 	struct bitcoin_signature sig;
 	struct privkey privkey;
 	bool testnet;
-	u32 locktime, htlc_abstimeout;
+	struct rel_locktime locktime;
+	struct abs_locktime htlc_abstimeout;
 	char *rvalue = NULL, *preimage = NULL;
 	bool received, own_commit_tx;
 	Pkt *pkt;
@@ -114,13 +116,13 @@ int main(int argc, char *argv[])
 
 	if (received) {
 		redeemscript = scriptpubkey_htlc_recv(ctx, &pubkey1, &pubkey2,
-						      htlc_abstimeout,
-						      locktime, &revoke_hash,
+						      &htlc_abstimeout,
+						      &locktime, &revoke_hash,
 						      &htlc_rhash);
 	} else {
 		redeemscript = scriptpubkey_htlc_send(ctx, &pubkey1, &pubkey2,
-						      htlc_abstimeout,
-						      locktime, &revoke_hash,
+						      &htlc_abstimeout,
+						      &locktime, &revoke_hash,
 						      &htlc_rhash);
 	}
 
@@ -163,14 +165,14 @@ int main(int argc, char *argv[])
 
 	if (!secret_len) {
 		/* We must be relying on HTLC timeout. */
-		tx->lock_time = htlc_abstimeout;
+		tx->lock_time = htlc_abstimeout.locktime;
 		/* Locktime only applies if an input has seq != ffffffff... */
 		tx->input[0].sequence_number = 0;
 	}
 
 	/* If it's our own commit tx, we also need delay. */
 	if (own_commit_tx)
-		tx->input[0].sequence_number = bitcoin_nsequence(locktime);
+		tx->input[0].sequence_number = bitcoin_nsequence(&locktime);
 
 	/* Leave 10,000 satoshi as fee (if we can!). */
 	tx->fee = 10000;

test-cli/create-steal-tx.c

@@ -15,6 +15,7 @@
 #include "bitcoin/privkey.h"
 #include "protobuf_convert.h"
 #include "version.h"
+#include "bitcoin/locktime.h"
 #include <unistd.h>
 
 int main(int argc, char *argv[])
@@ -30,7 +31,7 @@ int main(int argc, char *argv[])
 	struct bitcoin_signature sig;
 	struct privkey privkey;
 	bool testnet;
-	u32 locktime_seconds;
+	struct rel_locktime locktime;
 
 	err_set_progname(argv[0]);
 
@@ -68,7 +69,7 @@ int main(int argc, char *argv[])
 
 	o1 = pkt_from_file(argv[4], PKT__PKT_OPEN)->open;
 	o2 = pkt_from_file(argv[5], PKT__PKT_OPEN)->open;
-	if (!proto_to_rel_locktime(o1->delay, &locktime_seconds))
+	if (!proto_to_rel_locktime(o1->delay, &locktime))
 		errx(1, "Invalid locktime in o2");
 
 	if (!pubkey_from_hexstr(argv[6], &outpubkey))
@@ -85,7 +86,7 @@ int main(int argc, char *argv[])
 	/* Now, which commit output?  Match redeem script. */
 	sha256(&revoke_hash, &revoke_preimage, sizeof(revoke_preimage));
 	redeemscript = bitcoin_redeem_secret_or_delay(ctx, &pubkey2,
-						      locktime_seconds,
+						      &locktime,
 						      &pubkey1, &revoke_hash);
 	p2sh = scriptpubkey_p2sh(ctx, redeemscript);