usual dance; fetch.sh and send.sh fully passes.

diff 05db677d577e42756e296c0262a02c65bfd614fb refs/heads/w
commit - 05db677d577e42756e296c0262a02c65bfd614fb
commit + f2f9d6049f560b07591f71ccccdb8eed2f5022a4
blob - 6a64f1edca2e533d797c2fc7ebd6e8d738023fa4
blob + 151e0d73fa443289c8609863654c6bef6d128723
--- lib/got_lib_privsep.h
+++ lib/got_lib_privsep.h
@@ -458,7 +458,7 @@ struct got_imsg_send_ref {
 
 /* Structure for GOT_IMSG_SEND_REF data. */
 struct got_imsg_send_ref {
-	uint8_t id[SHA1_DIGEST_LENGTH];
+	struct got_object_id id;
 	int delete;
 	size_t name_len;
 	/* Followed by name_len data bytes. */
@@ -466,7 +466,7 @@ struct got_imsg_send_remote_ref {
 
 /* Structure for GOT_IMSG_SEND_REMOTE_REF data. */
 struct got_imsg_send_remote_ref {
-	uint8_t id[SHA1_DIGEST_LENGTH];
+	struct got_object_id id;
 	size_t name_len;
 	/* Followed by name_len data bytes. */
 } __attribute__((__packed__));
blob - 16a24da99f408f5487194b9f4ff88b84b5add165
blob + 970978560467422ed3a634b6c3b86e48e6b49fd0
--- lib/privsep.c
+++ lib/privsep.c
@@ -816,7 +816,7 @@ send_send_ref(const char *name, size_t name_len, struc
 		return got_error_from_errno("imsg_create SEND_REF");
 
 	/* Keep in sync with struct got_imsg_send_ref! */
-	if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1)
+	if (imsg_add(wbuf, id, sizeof(*id)) == -1)
 		return got_error_from_errno("imsg_add SEND_REF");
 	if (imsg_add(wbuf, &delete, sizeof(delete)) == -1)
 		return got_error_from_errno("imsg_add SEND_REF");
@@ -918,7 +918,7 @@ got_privsep_recv_send_remote_refs(struct got_pathlist_
 				err = got_error_from_errno("malloc");
 				goto done;
 			}
-			memcpy(id->sha1, iremote_ref.id, SHA1_DIGEST_LENGTH);
+			memcpy(id, &iremote_ref.id, sizeof(*id));
 			refname = strndup(imsg.data + sizeof(iremote_ref),
 			    datalen - sizeof(iremote_ref));
 			if (refname == NULL) {
blob - 40b31c00d9ba7fd602c0df52657c1340c932af57
blob + 0fd0e6b2e84bfc5519482bd5ae802897596069f2
--- libexec/got-send-pack/got-send-pack.c
+++ libexec/got-send-pack/got-send-pack.c
@@ -206,7 +206,7 @@ send_their_ref(struct imsgbuf *ibuf, struct got_object
 		return got_error_from_errno("imsg_create SEND_REMOTE_REF");
 
 	/* Keep in sync with struct got_imsg_send_remote_ref definition! */
-	if (imsg_add(wbuf, refid->sha1, SHA1_DIGEST_LENGTH) == -1)
+	if (imsg_add(wbuf, refid, sizeof(*refid)) == -1)
 		return got_error_from_errno("imsg_add SEND_REMOTE_REF");
 	if (imsg_add(wbuf, &reflen, sizeof(reflen)) == -1)
 		return got_error_from_errno("imsg_add SEND_REMOTE_REF");
@@ -704,7 +704,7 @@ main(int argc, char **argv)
 			err = got_error_from_errno("malloc");
 			goto done;
 		}
-		memcpy(id->sha1, href.id, SHA1_DIGEST_LENGTH);
+		memcpy(id, &href.id, sizeof(*id));
 		if (href.delete)
 			err = got_pathlist_append(&delete_refs, refname, id);
 		else