Convert struct object to object_id

struct object is one of the major data structures dealing with object
IDs.  Convert it to use struct object_id instead of an unsigned char
array.  Convert get_object_hash to refer to the new member as well.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Jeff King <peff@peff.net>

25 files changed, 125 insertions, 125 deletions

diff --git a/builtin/am.c b/builtin/am.c
index f1a25ab6ad..9fb42fdd71 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -1441,7 +1441,7 @@ static void get_commit_info(struct am_state *state, struct commit *commit)
 	assert(!state->msg);
 	msg = strstr(buffer, "\n\n");
 	if (!msg)
-		die(_("unable to parse commit %s"), sha1_to_hex(commit->object.sha1));
+		die(_("unable to parse commit %s"), oid_to_hex(&commit->object.oid));
 	state->msg = xstrdup(msg + 2);
 	state->msg_len = strlen(state->msg);
 }
diff --git a/builtin/blame.c b/builtin/blame.c
index c6ea9774b7..28c48bd453 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -557,7 +557,7 @@ static struct origin *find_origin(struct scoreboard *sb,
 		       PATHSPEC_LITERAL_PATH, "", paths);
 	diff_setup_done(&diff_opts);
 
-	if (is_null_sha1(origin->commit->object.sha1))
+	if (is_null_oid(&origin->commit->object.oid))
 		do_diff_cache(get_object_hash(parent->tree->object), &diff_opts);
 	else
 		diff_tree_sha1(get_object_hash(parent->tree->object),
@@ -627,7 +627,7 @@ static struct origin *find_rename(struct scoreboard *sb,
 	diff_opts.single_follow = origin->path;
 	diff_setup_done(&diff_opts);
 
-	if (is_null_sha1(origin->commit->object.sha1))
+	if (is_null_oid(&origin->commit->object.oid))
 		do_diff_cache(get_object_hash(parent->tree->object), &diff_opts);
 	else
 		diff_tree_sha1(get_object_hash(parent->tree->object),
@@ -977,8 +977,8 @@ static void pass_blame_to_parent(struct scoreboard *sb,
 
 	if (diff_hunks(&file_p, &file_o, 0, blame_chunk_cb, &d))
 		die("unable to generate diff (%s -> %s)",
-		    sha1_to_hex(parent->commit->object.sha1),
-		    sha1_to_hex(target->commit->object.sha1));
+		    oid_to_hex(&parent->commit->object.oid),
+		    oid_to_hex(&target->commit->object.oid));
 	/* The rest are the same as the parent */
 	blame_chunk(&d.dstq, &d.srcq, INT_MAX, d.offset, INT_MAX, parent);
 	*d.dstq = NULL;
@@ -1126,7 +1126,7 @@ static void find_copy_in_blob(struct scoreboard *sb,
 	memset(split, 0, sizeof(struct blame_entry [3]));
 	if (diff_hunks(file_p, &file_o, 1, handle_split_cb, &d))
 		die("unable to generate diff (%s)",
-		    sha1_to_hex(parent->commit->object.sha1));
+		    oid_to_hex(&parent->commit->object.oid));
 	/* remainder, if any, all match the preimage */
 	handle_split(sb, ent, d.tlno, d.plno, ent->num_lines, parent, split);
 }
@@ -1275,7 +1275,7 @@ static void find_copy_in_parent(struct scoreboard *sb,
 		&& (!porigin || strcmp(target->path, porigin->path))))
 		DIFF_OPT_SET(&diff_opts, FIND_COPIES_HARDER);
 
-	if (is_null_sha1(target->commit->object.sha1))
+	if (is_null_oid(&target->commit->object.oid))
 		do_diff_cache(get_object_hash(parent->tree->object), &diff_opts);
 	else
 		diff_tree_sha1(get_object_hash(parent->tree->object),
@@ -1690,7 +1690,7 @@ static void get_commit_info(struct commit *commit,
 	if (len)
 		strbuf_add(&ret->summary, subject, len);
 	else
-		strbuf_addf(&ret->summary, "(%s)", sha1_to_hex(commit->object.sha1));
+		strbuf_addf(&ret->summary, "(%s)", oid_to_hex(&commit->object.oid));
 
 	unuse_commit_buffer(commit, message);
 }
@@ -1733,7 +1733,7 @@ static int emit_one_suspect_detail(struct origin *suspect, int repeat)
 		printf("boundary\n");
 	if (suspect->previous) {
 		struct origin *prev = suspect->previous;
-		printf("previous %s ", sha1_to_hex(prev->commit->object.sha1));
+		printf("previous %s ", oid_to_hex(&prev->commit->object.oid));
 		write_name_quoted(prev->path, stdout, '\n');
 	}
 
@@ -1752,7 +1752,7 @@ static void found_guilty_entry(struct blame_entry *ent)
 		struct origin *suspect = ent->suspect;
 
 		printf("%s %d %d %d\n",
-		       sha1_to_hex(suspect->commit->object.sha1),
+		       oid_to_hex(&suspect->commit->object.oid),
 		       ent->s_lno + 1, ent->lno + 1, ent->num_lines);
 		emit_one_suspect_detail(suspect, 0);
 		write_filename_info(suspect->path);
@@ -1882,7 +1882,7 @@ static void emit_porcelain(struct scoreboard *sb, struct blame_entry *ent,
 	struct origin *suspect = ent->suspect;
 	char hex[GIT_SHA1_HEXSZ + 1];
 
-	sha1_to_hex_r(hex, suspect->commit->object.sha1);
+	sha1_to_hex_r(hex, suspect->commit->object.oid.hash);
 	printf("%s %d %d %d\n",
 	       hex,
 	       ent->s_lno + 1,
@@ -1922,7 +1922,7 @@ static void emit_other(struct scoreboard *sb, struct blame_entry *ent, int opt)
 	int show_raw_time = !!(opt & OUTPUT_RAW_TIMESTAMP);
 
 	get_commit_info(suspect->commit, &ci, 1);
-	sha1_to_hex_r(hex, suspect->commit->object.sha1);
+	sha1_to_hex_r(hex, suspect->commit->object.oid.hash);
 
 	cp = nth_line(sb, ent->lno);
 	for (cnt = 0; cnt < ent->num_lines; cnt++) {
@@ -2153,7 +2153,7 @@ static void sanity_check_refcnt(struct scoreboard *sb)
 		if (ent->suspect->refcnt <= 0) {
 			fprintf(stderr, "%s in %s has negative refcnt %d\n",
 				ent->suspect->path,
-				sha1_to_hex(ent->suspect->commit->object.sha1),
+				oid_to_hex(&ent->suspect->commit->object.oid),
 				ent->suspect->refcnt);
 			baa = 1;
 		}
@@ -2310,7 +2310,7 @@ static struct commit *fake_working_tree_commit(struct diff_options *opt,
 	strbuf_addstr(&msg, "tree 0000000000000000000000000000000000000000\n");
 	for (parent = commit->parents; parent; parent = parent->next)
 		strbuf_addf(&msg, "parent %s\n",
-			    sha1_to_hex(parent->item->object.sha1));
+			    oid_to_hex(&parent->item->object.oid));
 	strbuf_addf(&msg,
 		    "author %s\n"
 		    "committer %s\n\n"
@@ -2740,7 +2740,7 @@ parse_done:
 
 		sb.revs->children.name = "children";
 		while (c->parents &&
-		       hashcmp(c->object.sha1, sb.final->object.sha1)) {
+		       oidcmp(&c->object.oid, &sb.final->object.oid)) {
 			struct commit_list *l = xcalloc(1, sizeof(*l));
 
 			l->item = c;
@@ -2750,11 +2750,11 @@ parse_done:
 			c = c->parents->item;
 		}
 
-		if (hashcmp(c->object.sha1, sb.final->object.sha1))
+		if (oidcmp(&c->object.oid, &sb.final->object.oid))
 			die("--reverse --first-parent together require range along first-parent chain");
 	}
 
-	if (is_null_sha1(sb.final->object.sha1)) {
+	if (is_null_oid(&sb.final->object.oid)) {
 		o = sb.final->util;
 		sb.final_buf = xmemdupz(o->file.ptr, o->file.size);
 		sb.final_buf_size = o->file.size;
diff --git a/builtin/checkout.c b/builtin/checkout.c
index bca3a04c07..50fd893f7a 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -56,8 +56,8 @@ static int post_checkout_hook(struct commit *old, struct commit *new,
 			      int changed)
 {
 	return run_hook_le(NULL, "post-checkout",
-			   sha1_to_hex(old ? old->object.sha1 : null_sha1),
-			   sha1_to_hex(new ? new->object.sha1 : null_sha1),
+			   sha1_to_hex(old ? old->object.oid.hash : null_sha1),
+			   sha1_to_hex(new ? new->object.oid.hash : null_sha1),
 			   changed ? "1" : "0", NULL);
 	/* "new" can be NULL when checking out from the index before
 	   a commit exists. */
@@ -513,7 +513,7 @@ static int merge_working_tree(const struct checkout_opts *opts,
 					   get_object_hash(old->commit->object) :
 					   EMPTY_TREE_SHA1_BIN);
 		init_tree_desc(&trees[0], tree->buffer, tree->size);
-		tree = parse_tree_indirect(new->commit->object.sha1);
+		tree = parse_tree_indirect(new->commit->object.oid.hash);
 		init_tree_desc(&trees[1], tree->buffer, tree->size);
 
 		ret = unpack_trees(2, trees, &topts);
@@ -641,7 +641,7 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 
 	old_desc = old->name;
 	if (!old_desc && old->commit)
-		old_desc = sha1_to_hex(old->commit->object.sha1);
+		old_desc = oid_to_hex(&old->commit->object.oid);
 
 	reflog_msg = getenv("GIT_REFLOG_ACTION");
 	if (!reflog_msg)
@@ -780,10 +780,10 @@ static void orphaned_commit_warning(struct commit *old, struct commit *new)
 	setup_revisions(0, NULL, &revs, NULL);
 
 	object->flags &= ~UNINTERESTING;
-	add_pending_object(&revs, object, sha1_to_hex(object->sha1));
+	add_pending_object(&revs, object, oid_to_hex(&object->oid));
 
 	for_each_ref(add_pending_uninteresting_ref, &revs);
-	add_pending_sha1(&revs, "HEAD", new->object.sha1, UNINTERESTING);
+	add_pending_sha1(&revs, "HEAD", new->object.oid.hash, UNINTERESTING);
 
 	refs = revs.pending;
 	revs.leak_pending = 1;
diff --git a/builtin/commit-tree.c b/builtin/commit-tree.c
index 8747c0f2fb..3feeffeab1 100644
--- a/builtin/commit-tree.c
+++ b/builtin/commit-tree.c
@@ -16,11 +16,11 @@ static const char *sign_commit;
 
 static void new_parent(struct commit *parent, struct commit_list **parents_p)
 {
-	unsigned char *sha1 = parent->object.sha1;
+	struct object_id *oid = &parent->object.oid;
 	struct commit_list *parents;
 	for (parents = *parents_p; parents; parents = parents->next) {
 		if (parents->item == parent) {
-			error("duplicate parent %s ignored", sha1_to_hex(sha1));
+			error("duplicate parent %s ignored", oid_to_hex(oid));
 			return;
 		}
 		parents_p = &parents->next;
diff --git a/builtin/describe.c b/builtin/describe.c
index c0c373b418..11f7300aad 100644
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -267,7 +267,7 @@ static void describe(const char *arg, int last_one)
 	}
 
 	if (!max_candidates)
-		die(_("no tag exactly matches '%s'"), sha1_to_hex(cmit->object.sha1));
+		die(_("no tag exactly matches '%s'"), oid_to_hex(&cmit->object.oid));
 	if (debug)
 		fprintf(stderr, _("searching to describe %s\n"), arg);
 
@@ -317,7 +317,7 @@ static void describe(const char *arg, int last_one)
 		if (annotated_cnt && !list) {
 			if (debug)
 				fprintf(stderr, _("finished search at %s\n"),
-					sha1_to_hex(c->object.sha1));
+					oid_to_hex(&c->object.oid));
 			break;
 		}
 		while (parents) {
@@ -334,9 +334,9 @@ static void describe(const char *arg, int last_one)
 	}
 
 	if (!match_cnt) {
-		const unsigned char *sha1 = cmit->object.sha1;
+		struct object_id *oid = &cmit->object.oid;
 		if (always) {
-			printf("%s", find_unique_abbrev(sha1, abbrev));
+			printf("%s", find_unique_abbrev(oid->hash, abbrev));
 			if (dirty)
 				printf("%s", dirty);
 			printf("\n");
@@ -345,11 +345,11 @@ static void describe(const char *arg, int last_one)
 		if (unannotated_cnt)
 			die(_("No annotated tags can describe '%s'.\n"
 			    "However, there were unannotated tags: try --tags."),
-			    sha1_to_hex(sha1));
+			    oid_to_hex(oid));
 		else
 			die(_("No tags can describe '%s'.\n"
 			    "Try --always, or create some tags."),
-			    sha1_to_hex(sha1));
+			    oid_to_hex(oid));
 	}
 
 	qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
@@ -374,7 +374,7 @@ static void describe(const char *arg, int last_one)
 				_("more than %i tags found; listed %i most recent\n"
 				"gave up search at %s\n"),
 				max_candidates, max_candidates,
-				sha1_to_hex(gave_up_on->object.sha1));
+				oid_to_hex(&gave_up_on->object.oid));
 		}
 	}
 
diff --git a/builtin/diff-tree.c b/builtin/diff-tree.c
index cf7e9604b3..6fef266ea3 100644
--- a/builtin/diff-tree.c
+++ b/builtin/diff-tree.c
@@ -49,8 +49,8 @@ static int stdin_diff_trees(struct tree *tree1, char *line, int len)
 	tree2 = lookup_tree(sha1);
 	if (!tree2 || parse_tree(tree2))
 		return -1;
-	printf("%s %s\n", sha1_to_hex(tree1->object.sha1),
-			  sha1_to_hex(tree2->object.sha1));
+	printf("%s %s\n", oid_to_hex(&tree1->object.oid),
+			  oid_to_hex(&tree2->object.oid));
 	diff_tree_sha1(get_object_hash(tree1->object), get_object_hash(tree2->object),
 		       "", &log_tree_opt.diffopt);
 	log_tree_diff_flush(&log_tree_opt);
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index 30faf248f7..1337a2385a 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -544,13 +544,13 @@ static void handle_commit(struct commit *commit, struct rev_info *rev)
 	author = strstr(commit_buffer, "\nauthor ");
 	if (!author)
 		die ("Could not find author in commit %s",
-		     sha1_to_hex(commit->object.sha1));
+		     oid_to_hex(&commit->object.oid));
 	author++;
 	author_end = strchrnul(author, '\n');
 	committer = strstr(author_end, "\ncommitter ");
 	if (!committer)
 		die ("Could not find committer in commit %s",
-		     sha1_to_hex(commit->object.sha1));
+		     oid_to_hex(&commit->object.oid));
 	committer++;
 	committer_end = strchrnul(committer, '\n');
 	message = strstr(committer_end, "\n\n");
@@ -661,13 +661,13 @@ static void handle_tag(const char *name, struct tag *tag)
 	}
 	if (tagged->type == OBJ_TREE) {
 		warning("Omitting tag %s,\nsince tags of trees (or tags of tags of trees, etc.) are not supported.",
-			sha1_to_hex(tag->object.sha1));
+			oid_to_hex(&tag->object.oid));
 		return;
 	}
 
 	buf = read_sha1_file(get_object_hash(tag->object), &type, &size);
 	if (!buf)
-		die ("Could not read tag %s", sha1_to_hex(tag->object.sha1));
+		die ("Could not read tag %s", oid_to_hex(&tag->object.oid));
 	message = memmem(buf, size, "\n\n", 2);
 	if (message) {
 		message += 2;
@@ -706,16 +706,16 @@ static void handle_tag(const char *name, struct tag *tag)
 			case ABORT:
 				die ("Encountered signed tag %s; use "
 				     "--signed-tags=<mode> to handle it.",
-				     sha1_to_hex(tag->object.sha1));
+				     oid_to_hex(&tag->object.oid));
 			case WARN:
 				warning ("Exporting signed tag %s",
-					 sha1_to_hex(tag->object.sha1));
+					 oid_to_hex(&tag->object.oid));
 				/* fallthru */
 			case VERBATIM:
 				break;
 			case WARN_STRIP:
 				warning ("Stripping signature from tag %s",
-					 sha1_to_hex(tag->object.sha1));
+					 oid_to_hex(&tag->object.oid));
 				/* fallthru */
 			case STRIP:
 				message_size = signature + 1 - message;
@@ -731,14 +731,14 @@ static void handle_tag(const char *name, struct tag *tag)
 		case ABORT:
 			die ("Tag %s tags unexported object; use "
 			     "--tag-of-filtered-object=<mode> to handle it.",
-			     sha1_to_hex(tag->object.sha1));
+			     oid_to_hex(&tag->object.oid));
 		case DROP:
 			/* Ignore this tag altogether */
 			return;
 		case REWRITE:
 			if (tagged->type != OBJ_COMMIT) {
 				die ("Tag %s tags unexported %s!",
-				     sha1_to_hex(tag->object.sha1),
+				     oid_to_hex(&tag->object.oid),
 				     typename(tagged->type));
 			}
 			p = (struct commit *)tagged;
@@ -751,7 +751,7 @@ static void handle_tag(const char *name, struct tag *tag)
 					break;
 				if (!p->parents)
 					die ("Can't find replacement commit for tag %s\n",
-					     sha1_to_hex(tag->object.sha1));
+					     oid_to_hex(&tag->object.oid));
 				p = p->parents->item;
 			}
 			tagged_mark = get_object_mark(&p->object);
@@ -888,7 +888,7 @@ static void export_marks(char *file)
 		if (deco->base && deco->base->type == 1) {
 			mark = ptr_to_mark(deco->decoration);
 			if (fprintf(f, ":%"PRIu32" %s\n", mark,
-				sha1_to_hex(deco->base->sha1)) < 0) {
+				oid_to_hex(&deco->base->oid)) < 0) {
 			    e = 1;
 			    break;
 			}
diff --git a/builtin/fmt-merge-msg.c b/builtin/fmt-merge-msg.c
index a1505002bd..12aba984eb 100644
--- a/builtin/fmt-merge-msg.c
+++ b/builtin/fmt-merge-msg.c
@@ -378,7 +378,7 @@ static void shortlog(const char *name,
 
 		if (!sb.len)
 			string_list_append(&subjects,
-					   sha1_to_hex(commit->object.sha1));
+					   oid_to_hex(&commit->object.oid));
 		else
 			string_list_append(&subjects, strbuf_detach(&sb, NULL));
 	}
diff --git a/builtin/fsck.c b/builtin/fsck.c
index 40206696cf..7bfb4938fb 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -67,7 +67,7 @@ static void objreport(struct object *obj, const char *msg_type,
 			const char *err)
 {
 	fprintf(stderr, "%s in %s %s: %s\n",
-		msg_type, typename(obj->type), sha1_to_hex(obj->sha1), err);
+		msg_type, typename(obj->type), oid_to_hex(&obj->oid), err);
 }
 
 static int objerror(struct object *obj, const char *err)
@@ -97,7 +97,7 @@ static int mark_object(struct object *obj, int type, void *data, struct fsck_opt
 	if (!obj) {
 		/* ... these references to parent->fld are safe here */
 		printf("broken link from %7s %s\n",
-			   typename(parent->type), sha1_to_hex(parent->sha1));
+			   typename(parent->type), oid_to_hex(&parent->oid));
 		printf("broken link from %7s %s\n",
 			   (type == OBJ_ANY ? "unknown" : typename(type)), "unknown");
 		errors_found |= ERROR_REACHABLE;
@@ -112,11 +112,11 @@ static int mark_object(struct object *obj, int type, void *data, struct fsck_opt
 		return 0;
 	obj->flags |= REACHABLE;
 	if (!(obj->flags & HAS_OBJ)) {
-		if (parent && !has_sha1_file(obj->sha1)) {
+		if (parent && !has_object_file(&obj->oid)) {
 			printf("broken link from %7s %s\n",
-				 typename(parent->type), sha1_to_hex(parent->sha1));
+				 typename(parent->type), oid_to_hex(&parent->oid));
 			printf("              to %7s %s\n",
-				 typename(obj->type), sha1_to_hex(obj->sha1));
+				 typename(obj->type), oid_to_hex(&obj->oid));
 			errors_found |= ERROR_REACHABLE;
 		}
 		return 1;
@@ -188,9 +188,9 @@ static void check_reachable_object(struct object *obj)
 	if (!(obj->flags & HAS_OBJ)) {
 		if (has_sha1_pack(get_object_hash(*obj)))
 			return; /* it is in pack - forget about it */
-		if (connectivity_only && has_sha1_file(obj->sha1))
+		if (connectivity_only && has_object_file(&obj->oid))
 			return;
-		printf("missing %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
+		printf("missing %s %s\n", typename(obj->type), oid_to_hex(&obj->oid));
 		errors_found |= ERROR_REACHABLE;
 		return;
 	}
@@ -215,7 +215,7 @@ static void check_unreachable_object(struct object *obj)
 	 * since this is something that is prunable.
 	 */
 	if (show_unreachable) {
-		printf("unreachable %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
+		printf("unreachable %s %s\n", typename(obj->type), oid_to_hex(&obj->oid));
 		return;
 	}
 
@@ -234,11 +234,11 @@ static void check_unreachable_object(struct object *obj)
 	if (!obj->used) {
 		if (show_dangling)
 			printf("dangling %s %s\n", typename(obj->type),
-			       sha1_to_hex(obj->sha1));
+			       oid_to_hex(&obj->oid));
 		if (write_lost_and_found) {
 			char *filename = git_pathdup("lost-found/%s/%s",
 				obj->type == OBJ_COMMIT ? "commit" : "other",
-				sha1_to_hex(obj->sha1));
+				oid_to_hex(&obj->oid));
 			FILE *f;
 
 			if (safe_create_leading_directories_const(filename)) {
@@ -252,7 +252,7 @@ static void check_unreachable_object(struct object *obj)
 				if (stream_blob_to_fd(fileno(f), get_object_hash(*obj), NULL, 1))
 					die_errno("Could not write '%s'", filename);
 			} else
-				fprintf(f, "%s\n", sha1_to_hex(obj->sha1));
+				fprintf(f, "%s\n", oid_to_hex(&obj->oid));
 			if (fclose(f))
 				die_errno("Could not finish '%s'",
 					  filename);
@@ -271,7 +271,7 @@ static void check_unreachable_object(struct object *obj)
 static void check_object(struct object *obj)
 {
 	if (verbose)
-		fprintf(stderr, "Checking %s\n", sha1_to_hex(obj->sha1));
+		fprintf(stderr, "Checking %s\n", oid_to_hex(&obj->oid));
 
 	if (obj->flags & REACHABLE)
 		check_reachable_object(obj);
@@ -307,7 +307,7 @@ static int fsck_obj(struct object *obj)
 
 	if (verbose)
 		fprintf(stderr, "Checking %s %s\n",
-			typename(obj->type), sha1_to_hex(obj->sha1));
+			typename(obj->type), oid_to_hex(&obj->oid));
 
 	if (fsck_walk(obj, NULL, &fsck_obj_options))
 		objerror(obj, "broken links");
@@ -326,15 +326,15 @@ static int fsck_obj(struct object *obj)
 		free_commit_buffer(commit);
 
 		if (!commit->parents && show_root)
-			printf("root %s\n", sha1_to_hex(commit->object.sha1));
+			printf("root %s\n", oid_to_hex(&commit->object.oid));
 	}
 
 	if (obj->type == OBJ_TAG) {
 		struct tag *tag = (struct tag *) obj;
 
 		if (show_tags && tag->tagged) {
-			printf("tagged %s %s", typename(tag->tagged->type), sha1_to_hex(tag->tagged->sha1));
-			printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
+			printf("tagged %s %s", typename(tag->tagged->type), oid_to_hex(&tag->tagged->oid));
+			printf(" (%s) in %s\n", tag->tag, oid_to_hex(&tag->object.oid));
 		}
 	}
 
diff --git a/builtin/grep.c b/builtin/grep.c
index 9c42fc03b9..ca3ceea42c 100644
--- a/builtin/grep.c
+++ b/builtin/grep.c
@@ -468,12 +468,12 @@ static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
 		int hit, len;
 
 		grep_read_lock();
-		data = read_object_with_reference(obj->sha1, tree_type,
+		data = read_object_with_reference(obj->oid.hash, tree_type,
 						  &size, NULL);
 		grep_read_unlock();
 
 		if (!data)
-			die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
+			die(_("unable to read tree (%s)"), oid_to_hex(&obj->oid));
 
 		len = name ? strlen(name) : 0;
 		strbuf_init(&base, PATH_MAX + len + 1);
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index b01a8c0e22..48b470dd7a 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -199,7 +199,7 @@ static int mark_link(struct object *obj, int type, void *data, struct fsck_optio
 		return -1;
 
 	if (type != OBJ_ANY && obj->type != type)
-		die(_("object type mismatch at %s"), sha1_to_hex(obj->sha1));
+		die(_("object type mismatch at %s"), oid_to_hex(&obj->oid));
 
 	obj->flags |= FLAG_LINK;
 	return 0;
@@ -220,10 +220,10 @@ static unsigned check_object(struct object *obj)
 		int type = sha1_object_info(get_object_hash(*obj), &size);
 		if (type <= 0)
 			die(_("did not receive expected object %s"),
-			      sha1_to_hex(obj->sha1));
+			      oid_to_hex(&obj->oid));
 		if (type != obj->type)
 			die(_("object %s: expected type %s, found %s"),
-			    sha1_to_hex(obj->sha1),
+			    oid_to_hex(&obj->oid),
 			    typename(obj->type), typename(type));
 		obj->flags |= FLAG_CHECKED;
 		return 1;
@@ -842,7 +842,7 @@ static void sha1_object(const void *data, struct object_entry *obj_entry,
 			    fsck_object(obj, buf, size, &fsck_options))
 				die(_("Error in object"));
 			if (fsck_walk(obj, NULL, &fsck_options))
-				die(_("Not all child objects of %s are reachable"), sha1_to_hex(obj->sha1));
+				die(_("Not all child objects of %s are reachable"), oid_to_hex(&obj->oid));
 
 			if (obj->type == OBJ_TREE) {
 				struct tree *item = (struct tree *) obj;
diff --git a/builtin/log.c b/builtin/log.c
index 0977c8248c..a16ec32434 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -570,7 +570,7 @@ int cmd_show(int argc, const char **argv, const char *prefix)
 			o = parse_object(get_object_hash(*t->tagged));
 			if (!o)
 				ret = error(_("Could not read object %s"),
-					    sha1_to_hex(t->tagged->sha1));
+					    oid_to_hex(&t->tagged->oid));
 			objects[i].item = o;
 			i--;
 			break;
@@ -896,8 +896,8 @@ static void add_branch_description(struct strbuf *buf, const char *branch_name)
 static char *find_branch_name(struct rev_info *rev)
 {
 	int i, positive = -1;
-	unsigned char branch_sha1[20];
-	const unsigned char *tip_sha1;
+	struct object_id branch_oid;
+	const struct object_id *tip_oid;
 	const char *ref, *v;
 	char *full_ref, *branch = NULL;
 
@@ -912,10 +912,10 @@ static char *find_branch_name(struct rev_info *rev)
 	if (positive < 0)
 		return NULL;
 	ref = rev->cmdline.rev[positive].name;
-	tip_sha1 = rev->cmdline.rev[positive].item->sha1;
-	if (dwim_ref(ref, strlen(ref), branch_sha1, &full_ref) &&
+	tip_oid = &rev->cmdline.rev[positive].item->oid;
+	if (dwim_ref(ref, strlen(ref), branch_oid.hash, &full_ref) &&
 	    skip_prefix(full_ref, "refs/heads/", &v) &&
-	    !hashcmp(tip_sha1, branch_sha1))
+	    !oidcmp(tip_oid, &branch_oid))
 		branch = xstrdup(v);
 	free(full_ref);
 	return branch;
@@ -1443,7 +1443,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 		/* Don't say anything if head and upstream are the same. */
 		if (rev.pending.nr == 2) {
 			struct object_array_entry *o = rev.pending.objects;
-			if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
+			if (oidcmp(&o[0].item->oid, &o[1].item->oid) == 0)
 				return 0;
 		}
 		get_patch_ids(&rev, &ids);
@@ -1550,7 +1550,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 					string_list_append(rev.ref_message_ids,
 							   rev.message_id);
 			}
-			gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
+			gen_message_id(&rev, oid_to_hex(&commit->object.oid));
 		}
 
 		if (!use_stdout &&
@@ -1675,7 +1675,7 @@ int cmd_cherry(int argc, const char **argv, const char *prefix)
 	/* Don't say anything if head and upstream are the same. */
 	if (revs.pending.nr == 2) {
 		struct object_array_entry *o = revs.pending.objects;
-		if (hashcmp(o[0].item->sha1, o[1].item->sha1) == 0)
+		if (oidcmp(&o[0].item->oid, &o[1].item->oid) == 0)
 			return 0;
 	}
 
diff --git a/builtin/merge-base.c b/builtin/merge-base.c
index 08a8217890..a8911626c2 100644
--- a/builtin/merge-base.c
+++ b/builtin/merge-base.c
@@ -16,7 +16,7 @@ static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
 		return 1;
 
 	while (result) {
-		printf("%s\n", sha1_to_hex(result->item->object.sha1));
+		printf("%s\n", oid_to_hex(&result->item->object.oid));
 		if (!show_all)
 			return 0;
 		result = result->next;
@@ -62,7 +62,7 @@ static int handle_independent(int count, const char **args)
 		return 1;
 
 	while (result) {
-		printf("%s\n", sha1_to_hex(result->item->object.sha1));
+		printf("%s\n", oid_to_hex(&result->item->object.oid));
 		result = result->next;
 	}
 	return 0;
@@ -83,7 +83,7 @@ static int handle_octopus(int count, const char **args, int show_all)
 		return 1;
 
 	while (result) {
-		printf("%s\n", sha1_to_hex(result->item->object.sha1));
+		printf("%s\n", oid_to_hex(&result->item->object.oid));
 		if (!show_all)
 			return 0;
 		result = result->next;
@@ -196,7 +196,7 @@ static int handle_fork_point(int argc, const char **argv)
 		goto cleanup_return;
 	}
 
-	printf("%s\n", sha1_to_hex(bases->item->object.sha1));
+	printf("%s\n", oid_to_hex(&bases->item->object.oid));
 
 cleanup_return:
 	free_commit_list(bases);
diff --git a/builtin/merge-tree.c b/builtin/merge-tree.c
index cf1cee1d56..e124886ef1 100644
--- a/builtin/merge-tree.c
+++ b/builtin/merge-tree.c
@@ -130,7 +130,7 @@ static void show_result_list(struct merge_list *entry)
 	do {
 		struct merge_list *link = entry->link;
 		static const char *desc[4] = { "result", "base", "our", "their" };
-		printf("  %-6s %o %s %s\n", desc[entry->stage], entry->mode, sha1_to_hex(entry->blob->object.sha1), entry->path);
+		printf("  %-6s %o %s %s\n", desc[entry->stage], entry->mode, oid_to_hex(&entry->blob->object.oid), entry->path);
 		entry = link;
 	} while (entry);
 }
diff --git a/builtin/merge.c b/builtin/merge.c
index a6e598d957..c804218fb4 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -365,7 +365,7 @@ static void squash_message(struct commit *commit, struct commit_list *remotehead
 	while ((commit = get_revision(&rev)) != NULL) {
 		strbuf_addch(&out, '\n');
 		strbuf_addf(&out, "commit %s\n",
-			sha1_to_hex(get_object_hash(commit->object)));
+			oid_to_hex(&commit->object.oid));
 		pretty_print_commit(&ctx, commit, &out);
 	}
 	if (write_in_full(fd, out.buf, out.len) != out.len)
@@ -958,14 +958,14 @@ static void write_merge_state(struct commit_list *remoteheads)
 	struct strbuf buf = STRBUF_INIT;
 
 	for (j = remoteheads; j; j = j->next) {
-		unsigned const char *sha1;
+		struct object_id *oid;
 		struct commit *c = j->item;
 		if (c->util && merge_remote_util(c)->obj) {
-			sha1 = merge_remote_util(c)->obj->sha1;
+			oid = &merge_remote_util(c)->obj->oid;
 		} else {
-			sha1 = get_object_hash(c->object);
+			oid = &c->object.oid;
 		}
-		strbuf_addf(&buf, "%s\n", sha1_to_hex(sha1));
+		strbuf_addf(&buf, "%s\n", oid_to_hex(oid));
 	}
 	filename = git_path_merge_head();
 	fd = open(filename, O_WRONLY | O_CREAT, 0666);
diff --git a/builtin/name-rev.c b/builtin/name-rev.c
index cac66a5891..49e6e91b15 100644
--- a/builtin/name-rev.c
+++ b/builtin/name-rev.c
@@ -232,19 +232,19 @@ static void show_name(const struct object *obj,
 		      int always, int allow_undefined, int name_only)
 {
 	const char *name;
-	const unsigned char *sha1 = get_object_hash(*obj);
+	const struct object_id *oid = &obj->oid;
 
 	if (!name_only)
-		printf("%s ", caller_name ? caller_name : sha1_to_hex(sha1));
+		printf("%s ", caller_name ? caller_name : oid_to_hex(oid));
 	name = get_rev_name(obj);
 	if (name)
 		printf("%s\n", name);
 	else if (allow_undefined)
 		printf("undefined\n");
 	else if (always)
-		printf("%s\n", find_unique_abbrev(sha1, DEFAULT_ABBREV));
+		printf("%s\n", find_unique_abbrev(oid->hash, DEFAULT_ABBREV));
 	else
-		die("cannot describe '%s'", sha1_to_hex(sha1));
+		die("cannot describe '%s'", oid_to_hex(oid));
 }
 
 static char const * const name_rev_usage[] = {
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index b2d3e4ea27..fa1b5cd716 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -2338,7 +2338,7 @@ static int ofscmp(const void *a_, const void *b_)
 	else if (a->offset > b->offset)
 		return 1;
 	else
-		return hashcmp(a->object->sha1, b->object->sha1);
+		return oidcmp(&a->object->oid, &b->object->oid);
 }
 
 static void add_objects_in_unpacked_packs(struct rev_info *revs)
diff --git a/builtin/pull.c b/builtin/pull.c
index bf3fd3f9c8..4b7e344ac4 100644
--- a/builtin/pull.c
+++ b/builtin/pull.c
@@ -743,7 +743,7 @@ static int get_octopus_merge_base(unsigned char *merge_base,
 	if (!result)
 		return 1;
 
-	hashcpy(merge_base, result->item->object.sha1);
+	hashcpy(merge_base, get_object_hash(result->item->object));
 	return 0;
 }
 
diff --git a/builtin/replace.c b/builtin/replace.c
index 6b3c469a33..748c6ca954 100644
--- a/builtin/replace.c
+++ b/builtin/replace.c
@@ -358,10 +358,10 @@ static void check_one_mergetag(struct commit *commit,
 
 	/* iterate over new parents */
 	for (i = 1; i < mergetag_data->argc; i++) {
-		unsigned char sha1[20];
-		if (get_sha1(mergetag_data->argv[i], sha1) < 0)
+		struct object_id oid;
+		if (get_sha1(mergetag_data->argv[i], oid.hash) < 0)
 			die(_("Not a valid object name: '%s'"), mergetag_data->argv[i]);
-		if (!hashcmp(tag->tagged->sha1, sha1))
+		if (!oidcmp(&tag->tagged->oid, &oid))
 			return; /* found */
 	}
 
diff --git a/builtin/reset.c b/builtin/reset.c
index 9b88988183..d0014b6258 100644
--- a/builtin/reset.c
+++ b/builtin/reset.c
@@ -269,7 +269,7 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 	int reset_type = NONE, update_ref_status = 0, quiet = 0;
 	int patch_mode = 0, unborn;
 	const char *rev;
-	unsigned char sha1[20];
+	struct object_id oid;
 	struct pathspec pathspec;
 	int intent_to_add = 0;
 	const struct option options[] = {
@@ -295,26 +295,26 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 						PARSE_OPT_KEEP_DASHDASH);
 	parse_args(&pathspec, argv, prefix, patch_mode, &rev);
 
-	unborn = !strcmp(rev, "HEAD") && get_sha1("HEAD", sha1);
+	unborn = !strcmp(rev, "HEAD") && get_sha1("HEAD", oid.hash);
 	if (unborn) {
 		/* reset on unborn branch: treat as reset to empty tree */
-		hashcpy(sha1, EMPTY_TREE_SHA1_BIN);
+		hashcpy(oid.hash, EMPTY_TREE_SHA1_BIN);
 	} else if (!pathspec.nr) {
 		struct commit *commit;
-		if (get_sha1_committish(rev, sha1))
+		if (get_sha1_committish(rev, oid.hash))
 			die(_("Failed to resolve '%s' as a valid revision."), rev);
-		commit = lookup_commit_reference(sha1);
+		commit = lookup_commit_reference(oid.hash);
 		if (!commit)
 			die(_("Could not parse object '%s'."), rev);
-		hashcpy(sha1, commit->object.sha1);
+		oidcpy(&oid, &commit->object.oid);
 	} else {
 		struct tree *tree;
-		if (get_sha1_treeish(rev, sha1))
+		if (get_sha1_treeish(rev, oid.hash))
 			die(_("Failed to resolve '%s' as a valid tree."), rev);
-		tree = parse_tree_indirect(sha1);
+		tree = parse_tree_indirect(oid.hash);
 		if (!tree)
 			die(_("Could not parse object '%s'."), rev);
-		hashcpy(sha1, tree->object.sha1);
+		oidcpy(&oid, &tree->object.oid);
 	}
 
 	if (patch_mode) {
@@ -357,15 +357,15 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 		hold_locked_index(lock, 1);
 		if (reset_type == MIXED) {
 			int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
-			if (read_from_tree(&pathspec, sha1, intent_to_add))
+			if (read_from_tree(&pathspec, oid.hash, intent_to_add))
 				return 1;
 			if (get_git_work_tree())
 				refresh_index(&the_index, flags, NULL, NULL,
 					      _("Unstaged changes after reset:"));
 		} else {
-			int err = reset_index(sha1, reset_type, quiet);
+			int err = reset_index(oid.hash, reset_type, quiet);
 			if (reset_type == KEEP && !err)
-				err = reset_index(sha1, MIXED, quiet);
+				err = reset_index(oid.hash, MIXED, quiet);
 			if (err)
 				die(_("Could not reset index file to revision '%s'."), rev);
 		}
@@ -377,10 +377,10 @@ int cmd_reset(int argc, const char **argv, const char *prefix)
 	if (!pathspec.nr && !unborn) {
 		/* Any resets without paths update HEAD to the head being
 		 * switched to, saving the previous head in ORIG_HEAD before. */
-		update_ref_status = reset_refs(rev, sha1);
+		update_ref_status = reset_refs(rev, oid.hash);
 
 		if (reset_type == HARD && !update_ref_status && !quiet)
-			print_new_head_line(lookup_commit_reference(sha1));
+			print_new_head_line(lookup_commit_reference(oid.hash));
 	}
 	if (!pathspec.nr)
 		remove_branch_state();
diff --git a/builtin/rev-list.c b/builtin/rev-list.c
index 1cd5db1ae5..c4166ea7df 100644
--- a/builtin/rev-list.c
+++ b/builtin/rev-list.c
@@ -84,11 +84,11 @@ static void show_commit(struct commit *commit, void *data)
 		fputs(find_unique_abbrev(get_object_hash(commit->object), revs->abbrev),
 		      stdout);
 	else
-		fputs(sha1_to_hex(commit->object.sha1), stdout);
+		fputs(oid_to_hex(&commit->object.oid), stdout);
 	if (revs->print_parents) {
 		struct commit_list *parents = commit->parents;
 		while (parents) {
-			printf(" %s", sha1_to_hex(parents->item->object.sha1));
+			printf(" %s", oid_to_hex(&parents->item->object.oid));
 			parents = parents->next;
 		}
 	}
@@ -97,7 +97,7 @@ static void show_commit(struct commit *commit, void *data)
 
 		children = lookup_decoration(&revs->children, &commit->object);
 		while (children) {
-			printf(" %s", sha1_to_hex(children->item->object.sha1));
+			printf(" %s", oid_to_hex(&children->item->object.oid));
 			children = children->next;
 		}
 	}
@@ -182,8 +182,8 @@ static void finish_object(struct object *obj,
 			  void *cb_data)
 {
 	struct rev_list_info *info = cb_data;
-	if (obj->type == OBJ_BLOB && !has_sha1_file(obj->sha1))
-		die("missing blob object '%s'", sha1_to_hex(obj->sha1));
+	if (obj->type == OBJ_BLOB && !has_object_file(&obj->oid))
+		die("missing blob object '%s'", oid_to_hex(&obj->oid));
 	if (info->revs->verify_objects && !obj->parsed && obj->type != OBJ_COMMIT)
 		parse_object(get_object_hash(*obj));
 }
@@ -201,7 +201,7 @@ static void show_object(struct object *obj,
 
 static void show_edge(struct commit *commit)
 {
-	printf("-%s\n", sha1_to_hex(commit->object.sha1));
+	printf("-%s\n", oid_to_hex(&commit->object.oid));
 }
 
 static void print_var_str(const char *var, const char *val)
@@ -242,7 +242,7 @@ static int show_bisect_vars(struct rev_list_info *info, int reaches, int all)
 		cnt = reaches;
 
 	if (revs->commits)
-		sha1_to_hex_r(hex, revs->commits->item->object.sha1);
+		sha1_to_hex_r(hex, revs->commits->item->object.oid.hash);
 
 	if (flags & BISECT_SHOW_ALL) {
 		traverse_commit_list(revs, show_commit, show_object, info);
diff --git a/builtin/shortlog.c b/builtin/shortlog.c
index 007cc66a03..35ebd17f80 100644
--- a/builtin/shortlog.c
+++ b/builtin/shortlog.c
@@ -129,7 +129,7 @@ void shortlog_add_commit(struct shortlog *log, struct commit *commit)
 	}
 	if (!author) {
 		warning(_("Missing author: %s"),
-		    sha1_to_hex(commit->object.sha1));
+		    oid_to_hex(&commit->object.oid));
 		return;
 	}
 	if (log->user_format) {
diff --git a/builtin/show-branch.c b/builtin/show-branch.c
index eb88570501..1828640909 100644
--- a/builtin/show-branch.c
+++ b/builtin/show-branch.c
@@ -496,7 +496,7 @@ static int show_merge_base(struct commit_list *seen, int num_rev)
 		int flags = commit->object.flags & all_mask;
 		if (!(flags & UNINTERESTING) &&
 		    ((flags & all_revs) == all_revs)) {
-			puts(sha1_to_hex(commit->object.sha1));
+			puts(oid_to_hex(&commit->object.oid));
 			exit_status = 0;
 			commit->object.flags |= UNINTERESTING;
 		}
@@ -516,7 +516,7 @@ static int show_independent(struct commit **rev,
 		unsigned int flag = rev_mask[i];
 
 		if (commit->object.flags == flag)
-			puts(sha1_to_hex(commit->object.sha1));
+			puts(oid_to_hex(&commit->object.oid));
 		commit->object.flags |= UNINTERESTING;
 	}
 	return 0;
diff --git a/builtin/unpack-objects.c b/builtin/unpack-objects.c
index 1cf2806eea..61a3378896 100644
--- a/builtin/unpack-objects.c
+++ b/builtin/unpack-objects.c
@@ -46,7 +46,7 @@ static void add_object_buffer(struct object *object, char *buffer, unsigned long
 	obj->buffer = buffer;
 	obj->size = size;
 	if (add_decoration(&obj_decorate, object, obj))
-		die("object %s tried to add buffer twice!", sha1_to_hex(object->sha1));
+		die("object %s tried to add buffer twice!", oid_to_hex(&object->oid));
 }
 
 /*
@@ -170,7 +170,7 @@ static void write_cached_object(struct object *obj, struct obj_buffer *obj_buf)
 	unsigned char sha1[20];
 
 	if (write_sha1_file(obj_buf->buffer, obj_buf->size, typename(obj->type), sha1) < 0)
-		die("failed to write object %s", sha1_to_hex(obj->sha1));
+		die("failed to write object %s", oid_to_hex(&obj->oid));
 	obj->flags |= FLAG_WRITTEN;
 }
 
@@ -203,12 +203,12 @@ static int check_object(struct object *obj, int type, void *data, struct fsck_op
 
 	obj_buf = lookup_object_buffer(obj);
 	if (!obj_buf)
-		die("Whoops! Cannot find object '%s'", sha1_to_hex(obj->sha1));
+		die("Whoops! Cannot find object '%s'", oid_to_hex(&obj->oid));
 	if (fsck_object(obj, obj_buf->buffer, obj_buf->size, &fsck_options))
 		die("Error in object");
 	fsck_options.walk = check_object;
 	if (fsck_walk(obj, NULL, &fsck_options))
-		die("Error on reachable objects of %s", sha1_to_hex(obj->sha1));
+		die("Error on reachable objects of %s", oid_to_hex(&obj->oid));
 	write_cached_object(obj, obj_buf);
 	return 0;
 }
diff --git a/builtin/worktree.c b/builtin/worktree.c
index d281f6d887..475b9581a5 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -277,7 +277,7 @@ static int add_worktree(const char *path, const char *refname,
 
 	if (commit)
 		argv_array_pushl(&cp.args, "update-ref", "HEAD",
-				 sha1_to_hex(commit->object.sha1), NULL);
+				 oid_to_hex(&commit->object.oid), NULL);
 	else
 		argv_array_pushl(&cp.args, "symbolic-ref", "HEAD",
 				 symref.buf, NULL);