odb_loose: SHA256 support for loose object storageethomson/sha256_loose

Teach the loose object database how to cope with SHA256 objects.

5 files changed, 515 insertions, 70 deletions

diff --git a/include/git2/odb_backend.h b/include/git2/odb_backend.h
index d65aeec5a..092eb91ae 100644
--- a/include/git2/odb_backend.h
+++ b/include/git2/odb_backend.h
@@ -59,13 +59,19 @@ typedef struct {
 
 	/** Permissions to use creating a file or 0 for defaults */
 	unsigned int file_mode;
+
+	/**
+	 * Type of object IDs to use for this object database, or
+	 * 0 for default (currently SHA1).
+	 */
+	git_oid_t oid_type;
 } git_odb_backend_loose_options;
 
 /* The current version of the diff options structure */
 #define GIT_ODB_BACKEND_LOOSE_OPTIONS_VERSION 1
 
-/* Stack initializer for diff options.  Alternatively use
- * `git_diff_options_init` programmatic initialization.
+/* Stack initializer for odb loose backend options.  Alternatively use
+ * `git_odb_backend_loose_options_init` programmatic initialization.
  */
 #define GIT_ODB_BACKEND_LOOSE_OPTIONS_INIT \
 	{ GIT_ODB_BACKEND_LOOSE_OPTIONS_VERSION, 0, -1 }
diff --git a/src/odb.c b/src/odb.c
index 8662e80a3..d69f75221 100644
--- a/src/odb.c
+++ b/src/odb.c
@@ -669,6 +669,8 @@ int git_odb__add_default_backends(
 	if (db->do_fsync)
 		loose_opts.flags |= GIT_ODB_BACKEND_LOOSE_FSYNC;
 
+	loose_opts.oid_type = db->options.oid_type;
+
 	/* add the loose object backend */
 	if (git_odb_backend_loose(&loose, objects_dir, &loose_opts) < 0 ||
 		add_backend_internal(db, loose, git_odb__loose_priority, as_alternates, inode) < 0)
diff --git a/src/odb_loose.c b/src/odb_loose.c
index 1885fa293..f47ed50b8 100644
--- a/src/odb_loose.c
+++ b/src/odb_loose.c
@@ -47,6 +47,7 @@ typedef struct loose_backend {
 	git_odb_backend parent;
 
 	git_odb_backend_loose_options options;
+	size_t oid_hexsize;
 
 	size_t objects_dirlen;
 	char objects_dir[GIT_FLEX_ARRAY];
@@ -56,13 +57,19 @@ typedef struct loose_backend {
  * in order to locate objects matching a short oid.
  */
 typedef struct {
+	loose_backend *backend;
+
 	size_t dir_len;
-	unsigned char short_oid[GIT_OID_SHA1_HEXSIZE]; /* hex formatted oid to match */
+
+	/* Hex formatted oid to match (and its length) */
+	unsigned char short_oid[GIT_OID_MAX_HEXSIZE];
 	size_t short_oid_len;
-	int found;				/* number of matching
-						 * objects already found */
-	unsigned char res_oid[GIT_OID_SHA1_HEXSIZE];	/* hex formatted oid of
-						 * the object found */
+
+	/* Number of matching objects found so far */
+	int found;
+
+	/* Hex formatted oid of the object found */
+	unsigned char res_oid[GIT_OID_MAX_HEXSIZE];
 } loose_locate_object_state;
 
 
@@ -75,20 +82,17 @@ typedef struct {
 static int object_file_name(
 	git_str *name, const loose_backend *be, const git_oid *id)
 {
-	size_t alloclen;
-
-	/* expand length for object root + 40 hex sha1 chars + 2 * '/' + '\0' */
-	GIT_ERROR_CHECK_ALLOC_ADD(&alloclen, be->objects_dirlen, GIT_OID_SHA1_HEXSIZE);
-	GIT_ERROR_CHECK_ALLOC_ADD(&alloclen, alloclen, 3);
-	if (git_str_grow(name, alloclen) < 0)
-		return -1;
+	/* append loose object filename: aa/aaa... (41 bytes plus NUL) */
+	size_t path_size = be->oid_hexsize + 1;
 
 	git_str_set(name, be->objects_dir, be->objects_dirlen);
 	git_fs_path_to_dir(name);
 
-	/* loose object filename: aa/aaa... (41 bytes) */
+	if (git_str_grow_by(name, path_size + 1) < 0)
+		return -1;
+
 	git_oid_pathfmt(name->ptr + name->size, id);
-	name->size += GIT_OID_SHA1_HEXSIZE + 1;
+	name->size += path_size;
 	name->ptr[name->size] = '\0';
 
 	return 0;
@@ -460,8 +464,9 @@ static int locate_object(
 /* Explore an entry of a directory and see if it matches a short oid */
 static int fn_locate_object_short_oid(void *state, git_str *pathbuf) {
 	loose_locate_object_state *sstate = (loose_locate_object_state *)state;
+	size_t hex_size = sstate->backend->oid_hexsize;
 
-	if (git_str_len(pathbuf) - sstate->dir_len != GIT_OID_SHA1_HEXSIZE - 2) {
+	if (git_str_len(pathbuf) - sstate->dir_len != hex_size - 2) {
 		/* Entry cannot be an object. Continue to next entry */
 		return 0;
 	}
@@ -476,7 +481,9 @@ static int fn_locate_object_short_oid(void *state, git_str *pathbuf) {
 			if (!sstate->found) {
 				sstate->res_oid[0] = sstate->short_oid[0];
 				sstate->res_oid[1] = sstate->short_oid[1];
-				memcpy(sstate->res_oid+2, pathbuf->ptr+sstate->dir_len, GIT_OID_SHA1_HEXSIZE-2);
+				memcpy(sstate->res_oid + 2,
+				       pathbuf->ptr+sstate->dir_len,
+				       hex_size - 2);
 			}
 			sstate->found++;
 		}
@@ -502,7 +509,7 @@ static int locate_object_short_oid(
 	int error;
 
 	/* prealloc memory for OBJ_DIR/xx/xx..38x..xx */
-	GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, dir_len, GIT_OID_SHA1_HEXSIZE);
+	GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, dir_len, backend->oid_hexsize);
 	GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, alloc_len, 3);
 	if (git_str_grow(object_location, alloc_len) < 0)
 		return -1;
@@ -526,6 +533,7 @@ static int locate_object_short_oid(
 		return git_odb__error_notfound("no matching loose object for prefix",
 			short_oid, len);
 
+	state.backend = backend;
 	state.dir_len = git_str_len(object_location);
 	state.short_oid_len = len;
 	state.found = 0;
@@ -544,12 +552,12 @@ static int locate_object_short_oid(
 		return git_odb__error_ambiguous("multiple matches in loose objects");
 
 	/* Convert obtained hex formatted oid to raw */
-	error = git_oid_fromstr(res_oid, (char *)state.res_oid, GIT_OID_SHA1);
+	error = git_oid_fromstr(res_oid, (char *)state.res_oid, backend->options.oid_type);
 	if (error)
 		return error;
 
 	/* Update the location according to the oid obtained */
-	GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, dir_len, GIT_OID_SHA1_HEXSIZE);
+	GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, dir_len, backend->oid_hexsize);
 	GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, alloc_len, 2);
 
 	git_str_truncate(object_location, dir_len);
@@ -558,20 +566,12 @@ static int locate_object_short_oid(
 
 	git_oid_pathfmt(object_location->ptr + dir_len, res_oid);
 
-	object_location->size += GIT_OID_SHA1_HEXSIZE + 1;
+	object_location->size +=  backend->oid_hexsize + 1;
 	object_location->ptr[object_location->size] = '\0';
 
 	return 0;
 }
 
-
-
-
-
-
-
-
-
 /***********************************************************
  *
  * LOOSE BACKEND PUBLIC API
@@ -594,7 +594,7 @@ static int loose_backend__read_header(size_t *len_p, git_object_t *type_p, git_o
 
 	if (locate_object(&object_path, (loose_backend *)backend, oid) < 0) {
 		error = git_odb__error_notfound("no matching loose object",
-			oid, GIT_OID_SHA1_HEXSIZE);
+			oid, ((struct loose_backend *)backend)->oid_hexsize);
 	} else if ((error = read_header_loose(&raw, &object_path)) == 0) {
 		*len_p = raw.len;
 		*type_p = raw.type;
@@ -616,7 +616,7 @@ static int loose_backend__read(void **buffer_p, size_t *len_p, git_object_t *typ
 
 	if (locate_object(&object_path, (loose_backend *)backend, oid) < 0) {
 		error = git_odb__error_notfound("no matching loose object",
-			oid, GIT_OID_SHA1_HEXSIZE);
+			oid, ((struct loose_backend *)backend)->oid_hexsize);
 	} else if ((error = read_loose(&raw, &object_path)) == 0) {
 		*buffer_p = raw.data;
 		*len_p = raw.len;
@@ -633,17 +633,19 @@ static int loose_backend__read_prefix(
 	void **buffer_p,
 	size_t *len_p,
 	git_object_t *type_p,
-	git_odb_backend *backend,
+	git_odb_backend *_backend,
 	const git_oid *short_oid,
 	size_t len)
 {
+	struct loose_backend *backend = (struct loose_backend *)_backend;
 	int error = 0;
 
-	GIT_ASSERT_ARG(len >= GIT_OID_MINPREFIXLEN && len <= GIT_OID_SHA1_HEXSIZE);
+	GIT_ASSERT_ARG(len >= GIT_OID_MINPREFIXLEN &&
+	               len <= backend->oid_hexsize);
 
-	if (len == GIT_OID_SHA1_HEXSIZE) {
+	if (len == backend->oid_hexsize) {
 		/* We can fall back to regular read method */
-		error = loose_backend__read(buffer_p, len_p, type_p, backend, short_oid);
+		error = loose_backend__read(buffer_p, len_p, type_p, _backend, short_oid);
 		if (!error)
 			git_oid_cpy(out_oid, short_oid);
 	} else {
@@ -702,15 +704,18 @@ static int loose_backend__exists_prefix(
 }
 
 struct foreach_state {
+	struct loose_backend *backend;
 	size_t dir_len;
 	git_odb_foreach_cb cb;
 	void *data;
 };
 
-GIT_INLINE(int) filename_to_oid(git_oid *oid, const char *ptr)
+GIT_INLINE(int) filename_to_oid(struct loose_backend *backend, git_oid *oid, const char *ptr)
 {
-	int v, i = 0;
-	if (strlen(ptr) != GIT_OID_SHA1_HEXSIZE+1)
+	int v;
+	size_t i = 0;
+
+	if (strlen(ptr) != backend->oid_hexsize + 1)
 		return -1;
 
 	if (ptr[2] != '/') {
@@ -724,7 +729,7 @@ GIT_INLINE(int) filename_to_oid(git_oid *oid, const char *ptr)
 	oid->id[0] = (unsigned char) v;
 
 	ptr += 3;
-	for (i = 0; i < 38; i += 2) {
+	for (i = 0; i < backend->oid_hexsize - 2; i += 2) {
 		v = (git__fromhex(ptr[i]) << 4) | git__fromhex(ptr[i + 1]);
 		if (v < 0)
 			return -1;
@@ -732,7 +737,7 @@ GIT_INLINE(int) filename_to_oid(git_oid *oid, const char *ptr)
 		oid->id[1 + i/2] = (unsigned char) v;
 	}
 
-	oid->type = GIT_OID_SHA1;
+	oid->type = backend->options.oid_type;
 
 	return 0;
 }
@@ -742,7 +747,7 @@ static int foreach_object_dir_cb(void *_state, git_str *path)
 	git_oid oid;
 	struct foreach_state *state = (struct foreach_state *) _state;
 
-	if (filename_to_oid(&oid, path->ptr + state->dir_len) < 0)
+	if (filename_to_oid(state->backend, &oid, path->ptr + state->dir_len) < 0)
 		return 0;
 
 	return git_error_set_after_callback_function(
@@ -779,6 +784,7 @@ static int loose_backend__foreach(git_odb_backend *_backend, git_odb_foreach_cb
 		return -1;
 
 	memset(&state, 0, sizeof(state));
+	state.backend = backend;
 	state.cb = cb;
 	state.data = data;
 	state.dir_len = git_str_len(&buf);
@@ -999,6 +1005,7 @@ static int loose_backend__readstream(
 	loose_readstream *stream = NULL;
 	git_hash_ctx *hash_ctx = NULL;
 	git_str object_path = GIT_STR_INIT;
+	git_hash_algorithm_t algorithm;
 	obj_hdr hdr;
 	int error = 0;
 
@@ -1015,7 +1022,7 @@ static int loose_backend__readstream(
 
 	if (locate_object(&object_path, backend, oid) < 0) {
 		error = git_odb__error_notfound("no matching loose object",
-			oid, GIT_OID_SHA1_HEXSIZE);
+			oid, backend->oid_hexsize);
 		goto done;
 	}
 
@@ -1025,9 +1032,11 @@ static int loose_backend__readstream(
 	hash_ctx = git__malloc(sizeof(git_hash_ctx));
 	GIT_ERROR_CHECK_ALLOC(hash_ctx);
 
-	if ((error = git_hash_ctx_init(hash_ctx, GIT_HASH_ALGORITHM_SHA1)) < 0 ||
-		(error = git_futils_mmap_ro_file(&stream->map, object_path.ptr)) < 0 ||
-		(error = git_zstream_init(&stream->zstream, GIT_ZSTREAM_INFLATE)) < 0)
+	algorithm = git_oid_algorithm(backend->options.oid_type);
+
+	if ((error = git_hash_ctx_init(hash_ctx, algorithm)) < 0 ||
+	    (error = git_futils_mmap_ro_file(&stream->map, object_path.ptr)) < 0 ||
+	    (error = git_zstream_init(&stream->zstream, GIT_ZSTREAM_INFLATE)) < 0)
 		goto done;
 
 	/* check for a packlike loose object */
@@ -1145,6 +1154,9 @@ static void normalize_options(
 
 	if (opts->file_mode == 0)
 		opts->file_mode = GIT_OBJECT_FILE_MODE;
+
+	if (opts->oid_type == 0)
+		opts->oid_type = GIT_OID_DEFAULT;
 }
 
 int git_odb_backend_loose(
@@ -1173,6 +1185,7 @@ int git_odb_backend_loose(
 		backend->objects_dir[backend->objects_dirlen++] = '/';
 
 	normalize_options(&backend->options, opts);
+	backend->oid_hexsize = git_oid_hexsize(backend->options.oid_type);
 
 	backend->parent.read = &loose_backend__read;
 	backend->parent.write = &loose_backend__write;
diff --git a/tests/odb/loose.c b/tests/odb/loose.c
index 20b329f69..9f57a6866 100644
--- a/tests/odb/loose.c
+++ b/tests/odb/loose.c
@@ -34,24 +34,27 @@ static void cmp_objects(git_rawobj *o, object_data *d)
 
 static void test_read_object(object_data *data)
 {
-    git_oid id;
-    git_odb_object *obj;
+	git_oid id;
+	git_odb_object *obj;
 	git_odb *odb;
 	git_rawobj tmp;
+	git_odb_options opts = GIT_ODB_OPTIONS_INIT;
+
+	opts.oid_type = data->id_type;
 
-    write_object_files(data);
+	write_object_files(data);
 
-    cl_git_pass(git_odb_open(&odb, "test-objects", NULL));
-    cl_git_pass(git_oid_fromstr(&id, data->id, GIT_OID_SHA1));
-    cl_git_pass(git_odb_read(&obj, odb, &id));
+	cl_git_pass(git_odb_open(&odb, "test-objects", &opts));
+	cl_git_pass(git_oid_fromstr(&id, data->id, data->id_type));
+	cl_git_pass(git_odb_read(&obj, odb, &id));
 
 	tmp.data = obj->buffer;
 	tmp.len = obj->cached.size;
 	tmp.type = obj->cached.type;
 
-    cmp_objects(&tmp, data);
+	cmp_objects(&tmp, data);
 
-    git_odb_object_free(obj);
+	git_odb_object_free(obj);
 	git_odb_free(odb);
 }
 
@@ -61,11 +64,14 @@ static void test_read_header(object_data *data)
 	git_odb *odb;
 	size_t len;
 	git_object_t type;
+	git_odb_options opts = GIT_ODB_OPTIONS_INIT;
+
+	opts.oid_type = data->id_type;
 
 	write_object_files(data);
 
-	cl_git_pass(git_odb_open(&odb, "test-objects", NULL));
-	cl_git_pass(git_oid_fromstr(&id, data->id, GIT_OID_SHA1));
+	cl_git_pass(git_odb_open(&odb, "test-objects", &opts));
+	cl_git_pass(git_oid_fromstr(&id, data->id, data->id_type));
 	cl_git_pass(git_odb_read_header(&len, &type, odb, &id));
 
 	cl_assert_equal_sz(data->dlen, len);
@@ -83,11 +89,14 @@ static void test_readstream_object(object_data *data, size_t blocksize)
 	char buf[2048], *ptr = buf;
 	size_t remain;
 	int ret;
+	git_odb_options opts = GIT_ODB_OPTIONS_INIT;
+
+	opts.oid_type = data->id_type;
 
 	write_object_files(data);
 
-	cl_git_pass(git_odb_open(&odb, "test-objects", NULL));
-	cl_git_pass(git_oid_fromstr(&id, data->id, GIT_OID_SHA1));
+	cl_git_pass(git_odb_open(&odb, "test-objects", &opts));
+	cl_git_pass(git_oid_fromstr(&id, data->id, data->id_type));
 	cl_git_pass(git_odb_open_rstream(&stream, &tmp.len, &tmp.type, odb, &id));
 
 	remain = tmp.len;
@@ -124,7 +133,7 @@ void test_odb_loose__cleanup(void)
 	cl_fixture_cleanup("test-objects");
 }
 
-void test_odb_loose__exists(void)
+void test_odb_loose__exists_sha1(void)
 {
 	git_oid id, id2;
 	git_odb *odb;
@@ -149,7 +158,35 @@ void test_odb_loose__exists(void)
 	git_odb_free(odb);
 }
 
-void test_odb_loose__simple_reads(void)
+void test_odb_loose__exists_sha256(void)
+{
+	git_oid id, id2;
+	git_odb *odb;
+	git_odb_options odb_opts = GIT_ODB_OPTIONS_INIT;
+
+	odb_opts.oid_type = GIT_OID_SHA256;
+
+	write_object_files(&one_sha256);
+	cl_git_pass(git_odb_open(&odb, "test-objects", &odb_opts));
+
+	cl_git_pass(git_oid_fromstr(&id, one_sha256.id, GIT_OID_SHA256));
+	cl_assert(git_odb_exists(odb, &id));
+
+	cl_git_pass(git_oid_fromstrp(&id, "4c0d52d1", GIT_OID_SHA256));
+	cl_git_pass(git_odb_exists_prefix(&id2, odb, &id, 8));
+	cl_assert_equal_i(0, git_oid_streq(&id2, one_sha256.id));
+
+	/* Test for a missing object */
+	cl_git_pass(git_oid_fromstr(&id, "4c0d52d180c61d01ce1a91dec5ee58f0cbe65fd59433aea803ab927965493faa", GIT_OID_SHA256));
+	cl_assert(!git_odb_exists(odb, &id));
+
+	cl_git_pass(git_oid_fromstrp(&id, "4c0d52da", GIT_OID_SHA256));
+	cl_assert_equal_i(GIT_ENOTFOUND, git_odb_exists_prefix(&id2, odb, &id, 8));
+
+	git_odb_free(odb);
+}
+
+void test_odb_loose__simple_reads_sha1(void)
 {
 	test_read_object(&commit);
 	test_read_object(&tree);
@@ -160,7 +197,18 @@ void test_odb_loose__simple_reads(void)
 	test_read_object(&some);
 }
 
-void test_odb_loose__streaming_reads(void)
+void test_odb_loose__simple_reads_sha256(void)
+{
+	test_read_object(&commit_sha256);
+	test_read_object(&tree_sha256);
+	test_read_object(&tag_sha256);
+	test_read_object(&zero_sha256);
+	test_read_object(&one_sha256);
+	test_read_object(&two_sha256);
+	test_read_object(&some_sha256);
+}
+
+void test_odb_loose__streaming_reads_sha1(void)
 {
 	size_t blocksizes[] = { 1, 2, 4, 16, 99, 1024, 123456789 };
 	size_t i;
@@ -176,7 +224,23 @@ void test_odb_loose__streaming_reads(void)
 	}
 }
 
-void test_odb_loose__read_header(void)
+void test_odb_loose__streaming_reads_sha256(void)
+{
+	size_t blocksizes[] = { 1, 2, 4, 16, 99, 1024, 123456789 };
+	size_t i;
+
+	for (i = 0; i < ARRAY_SIZE(blocksizes); i++) {
+		test_readstream_object(&commit_sha256, blocksizes[i]);
+		test_readstream_object(&tree_sha256, blocksizes[i]);
+		test_readstream_object(&tag_sha256, blocksizes[i]);
+		test_readstream_object(&zero_sha256, blocksizes[i]);
+		test_readstream_object(&one_sha256, blocksizes[i]);
+		test_readstream_object(&two_sha256, blocksizes[i]);
+		test_readstream_object(&some_sha256, blocksizes[i]);
+	}
+}
+
+void test_odb_loose__read_header_sha1(void)
 {
 	test_read_header(&commit);
 	test_read_header(&tree);
@@ -187,6 +251,17 @@ void test_odb_loose__read_header(void)
 	test_read_header(&some);
 }
 
+void test_odb_loose__read_header_sha256(void)
+{
+	test_read_header(&commit_sha256);
+	test_read_header(&tree_sha256);
+	test_read_header(&tag_sha256);
+	test_read_header(&zero_sha256);
+	test_read_header(&one_sha256);
+	test_read_header(&two_sha256);
+	test_read_header(&some_sha256);
+}
+
 static void test_write_object_permission(
 	mode_t dir_mode, mode_t file_mode,
 	mode_t expected_dir_mode, mode_t expected_file_mode)
diff --git a/tests/odb/loose_data.h b/tests/odb/loose_data.h
index c10c9bc7f..97681a014 100644
--- a/tests/odb/loose_data.h
+++ b/tests/odb/loose_data.h
@@ -1,7 +1,8 @@
 typedef struct object_data {
     unsigned char *bytes;  /* (compressed) bytes stored in object store */
     size_t        blen;    /* length of data in object store            */
-    char          *id;     /* object id (sha1)                          */
+    char          *id;     /* object id (hex chars)                     */
+    git_oid_t     id_type; /* type of object id (sha1 or sha256)        */
     char          *type;   /* object type                               */
     char          *dir;    /* object store (fan-out) directory name     */
     char          *file;   /* object store filename                     */
@@ -9,7 +10,10 @@ typedef struct object_data {
     size_t        dlen;    /* length of (uncompressed) object data      */
 } object_data;
 
-/* one == 8b137891791fe96927ad78e64b0aad7bded08bdc */
+/*
+ * one == 8b137891791fe96927ad78e64b0aad7bded08bdc (sha1)
+ * 4c0d52d180c61d01ce1a91dec5ee58f0cbe65fd59433aea803ab927965493fd7 (sha256)
+ */
 static unsigned char one_bytes[] = {
     0x31, 0x78, 0x9c, 0xe3, 0x02, 0x00, 0x00, 0x0b,
     0x00, 0x0b,
@@ -23,6 +27,7 @@ static object_data one = {
     one_bytes,
     sizeof(one_bytes),
     "8b137891791fe96927ad78e64b0aad7bded08bdc",
+    GIT_OID_SHA1,
     "blob",
     "test-objects/8b",
     "test-objects/8b/137891791fe96927ad78e64b0aad7bded08bdc",
@@ -30,8 +35,23 @@ static object_data one = {
     sizeof(one_data),
 };
 
+static object_data one_sha256 = {
+    one_bytes,
+    sizeof(one_bytes),
+    "4c0d52d180c61d01ce1a91dec5ee58f0cbe65fd59433aea803ab927965493fd7",
+    GIT_OID_SHA256,
+    "blob",
+    "test-objects/4c",
+    "test-objects/4c/0d52d180c61d01ce1a91dec5ee58f0cbe65fd59433aea803ab927965493fd7",
+    one_data,
+    sizeof(one_data),
+};
 
-/* commit == 3d7f8a6af076c8c3f20071a8935cdbe8228594d1 */
+
+/*
+ * commit == 3d7f8a6af076c8c3f20071a8935cdbe8228594d1 (sha1)
+ * a2a430fb63b294f868af4ef6ccc9c3e8256e370859ce578a23837ac85337f562 (sha256)
+ */
 static unsigned char commit_bytes[] = {
     0x78, 0x01, 0x85, 0x50, 0xc1, 0x6a, 0xc3, 0x30,
     0x0c, 0xdd, 0xd9, 0x5f, 0xa1, 0xfb, 0x96, 0x12,
@@ -64,6 +84,40 @@ static unsigned char commit_bytes[] = {
     0x1f, 0x78, 0x35,
 };
 
+static unsigned char commit_bytes_sha256[] = {
+    0x78, 0x01, 0x85, 0x90, 0xc1, 0x4e, 0xc3, 0x30,
+    0x0c, 0x86, 0x39, 0xe7, 0x29, 0x7c, 0x87, 0x4e,
+    0x5d, 0x93, 0xa6, 0x2d, 0x9a, 0x10, 0x13, 0x67,
+    0xc4, 0x81, 0xf1, 0x00, 0x4e, 0xe3, 0xb4, 0x91,
+    0x9a, 0xa4, 0x4a, 0x53, 0x69, 0x7d, 0x7b, 0x82,
+    0x3a, 0x4d, 0x9c, 0xc0, 0xa7, 0xcf, 0xbf, 0xfd,
+    0xff, 0xb2, 0xdc, 0x07, 0xe7, 0x6c, 0x02, 0xde,
+    0xb4, 0x0f, 0x29, 0x12, 0x01, 0x17, 0x28, 0xda,
+    0x5a, 0xa8, 0x5a, 0x54, 0xd2, 0x74, 0x95, 0x90,
+    0xa5, 0x12, 0x48, 0xbc, 0x26, 0xa9, 0x9b, 0xae,
+    0x11, 0x52, 0x91, 0x94, 0x3d, 0x6f, 0x95, 0x31,
+    0x5a, 0x92, 0xe1, 0xaa, 0x17, 0xa6, 0xac, 0x39,
+    0xe9, 0xa6, 0x45, 0x2e, 0x15, 0x0a, 0x86, 0x6b,
+    0x1a, 0x43, 0x84, 0x33, 0x7c, 0xc1, 0xe5, 0x07,
+    0x4e, 0xbb, 0xf0, 0x4a, 0x57, 0x74, 0xf3, 0x44,
+    0x87, 0x3e, 0xb8, 0x17, 0x38, 0x56, 0x55, 0xd3,
+    0x1e, 0x45, 0xd5, 0x35, 0xf0, 0x58, 0xe6, 0x62,
+    0x59, 0xcd, 0x67, 0x24, 0x8a, 0xf0, 0x06, 0x1f,
+    0xf0, 0xbe, 0xe3, 0xe9, 0xae, 0xfe, 0xe3, 0x66,
+    0x67, 0x08, 0x9e, 0x8a, 0xc9, 0x7a, 0x82, 0xdd,
+    0x03, 0xcb, 0xea, 0x1c, 0xc6, 0x8d, 0xb1, 0xcb,
+    0x48, 0xa0, 0x82, 0xde, 0x20, 0x18, 0x48, 0x99,
+    0x6f, 0x73, 0x47, 0xcb, 0x82, 0x03, 0x3d, 0xe5,
+    0xde, 0x27, 0xb4, 0xde, 0xfa, 0x01, 0xcc, 0x1a,
+    0xf3, 0x46, 0x04, 0xba, 0xce, 0x13, 0x7a, 0x4c,
+    0x36, 0x78, 0x76, 0x73, 0xcd, 0x6b, 0x9c, 0xc3,
+    0x42, 0xf7, 0x90, 0x11, 0xfd, 0x40, 0x0b, 0x58,
+    0x9f, 0x62, 0xd0, 0x6b, 0x4f, 0x1a, 0xd4, 0xf6,
+    0x2b, 0xfe, 0xc0, 0xd8, 0xa7, 0x1d, 0x3c, 0xe9,
+    0x22, 0x98, 0x42, 0x6d, 0xcf, 0x7f, 0xbf, 0x83,
+    0x7d, 0x03, 0x6d, 0x1e, 0x7e, 0xa9
+};
+
 static unsigned char commit_data[] = {
     0x74, 0x72, 0x65, 0x65, 0x20, 0x64, 0x66, 0x66,
     0x32, 0x64, 0x61, 0x39, 0x30, 0x62, 0x32, 0x35,
@@ -112,10 +166,62 @@ static unsigned char commit_data[] = {
     0x3e, 0x0a,
 };
 
+static unsigned char commit_data_sha256[] = {
+    0x74, 0x72, 0x65, 0x65, 0x20, 0x33, 0x34, 0x61,
+    0x34, 0x38, 0x35, 0x34, 0x62, 0x35, 0x34, 0x32,
+    0x36, 0x66, 0x39, 0x32, 0x34, 0x36, 0x30, 0x62,
+    0x34, 0x61, 0x65, 0x33, 0x35, 0x65, 0x36, 0x64,
+    0x37, 0x39, 0x37, 0x34, 0x36, 0x62, 0x65, 0x36,
+    0x36, 0x63, 0x33, 0x38, 0x62, 0x66, 0x66, 0x64,
+    0x36, 0x65, 0x66, 0x33, 0x62, 0x63, 0x34, 0x66,
+    0x30, 0x35, 0x33, 0x65, 0x64, 0x37, 0x38, 0x61,
+    0x33, 0x36, 0x62, 0x61, 0x34, 0x0a, 0x61, 0x75,
+    0x74, 0x68, 0x6f, 0x72, 0x20, 0x41, 0x20, 0x55,
+    0x20, 0x54, 0x68, 0x6f, 0x72, 0x20, 0x3c, 0x61,
+    0x75, 0x74, 0x68, 0x6f, 0x72, 0x40, 0x65, 0x78,
+    0x61, 0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f,
+    0x6d, 0x3e, 0x20, 0x31, 0x32, 0x32, 0x37, 0x38,
+    0x31, 0x34, 0x32, 0x39, 0x37, 0x20, 0x2b, 0x30,
+    0x30, 0x30, 0x30, 0x0a, 0x63, 0x6f, 0x6d, 0x6d,
+    0x69, 0x74, 0x74, 0x65, 0x72, 0x20, 0x43, 0x20,
+    0x4f, 0x20, 0x4d, 0x69, 0x74, 0x74, 0x65, 0x72,
+    0x20, 0x3c, 0x63, 0x6f, 0x6d, 0x6d, 0x69, 0x74,
+    0x74, 0x65, 0x72, 0x40, 0x65, 0x78, 0x61, 0x6d,
+    0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d, 0x3e,
+    0x20, 0x31, 0x32, 0x32, 0x37, 0x38, 0x31, 0x34,
+    0x32, 0x39, 0x37, 0x20, 0x2b, 0x30, 0x30, 0x30,
+    0x30, 0x0a, 0x0a, 0x41, 0x20, 0x6f, 0x6e, 0x65,
+    0x2d, 0x6c, 0x69, 0x6e, 0x65, 0x20, 0x63, 0x6f,
+    0x6d, 0x6d, 0x69, 0x74, 0x20, 0x73, 0x75, 0x6d,
+    0x6d, 0x61, 0x72, 0x79, 0x0a, 0x0a, 0x54, 0x68,
+    0x65, 0x20, 0x62, 0x6f, 0x64, 0x79, 0x20, 0x6f,
+    0x66, 0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6f,
+    0x6d, 0x6d, 0x69, 0x74, 0x20, 0x6d, 0x65, 0x73,
+    0x73, 0x61, 0x67, 0x65, 0x2c, 0x20, 0x63, 0x6f,
+    0x6e, 0x74, 0x61, 0x69, 0x6e, 0x69, 0x6e, 0x67,
+    0x20, 0x66, 0x75, 0x72, 0x74, 0x68, 0x65, 0x72,
+    0x20, 0x65, 0x78, 0x70, 0x6c, 0x61, 0x6e, 0x61,
+    0x74, 0x69, 0x6f, 0x6e, 0x0a, 0x6f, 0x66, 0x20,
+    0x74, 0x68, 0x65, 0x20, 0x70, 0x75, 0x72, 0x70,
+    0x6f, 0x73, 0x65, 0x20, 0x6f, 0x66, 0x20, 0x74,
+    0x68, 0x65, 0x20, 0x63, 0x68, 0x61, 0x6e, 0x67,
+    0x65, 0x73, 0x20, 0x69, 0x6e, 0x74, 0x72, 0x6f,
+    0x64, 0x75, 0x63, 0x65, 0x64, 0x20, 0x62, 0x79,
+    0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6f, 0x6d,
+    0x6d, 0x69, 0x74, 0x2e, 0x0a, 0x0a, 0x53, 0x69,
+    0x67, 0x6e, 0x65, 0x64, 0x2d, 0x6f, 0x66, 0x2d,
+    0x62, 0x79, 0x3a, 0x20, 0x41, 0x20, 0x55, 0x20,
+    0x54, 0x68, 0x6f, 0x72, 0x20, 0x3c, 0x61, 0x75,
+    0x74, 0x68, 0x6f, 0x72, 0x40, 0x65, 0x78, 0x61,
+    0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d,
+    0x3e, 0x0a
+};
+
 static object_data commit = {
     commit_bytes,
     sizeof(commit_bytes),
     "3d7f8a6af076c8c3f20071a8935cdbe8228594d1",
+    GIT_OID_SHA1,
     "commit",
     "test-objects/3d",
     "test-objects/3d/7f8a6af076c8c3f20071a8935cdbe8228594d1",
@@ -123,7 +229,22 @@ static object_data commit = {
     sizeof(commit_data),
 };
 
-/* tree == dff2da90b254e1beb889d1f1f1288be1803782df */
+static object_data commit_sha256 = {
+    commit_bytes_sha256,
+    sizeof(commit_bytes_sha256),
+    "a2a430fb63b294f868af4ef6ccc9c3e8256e370859ce578a23837ac85337f562",
+    GIT_OID_SHA256,
+    "commit",
+    "test-objects/a2",
+    "test-objects/a2/a430fb63b294f868af4ef6ccc9c3e8256e370859ce578a23837ac85337f562",
+    commit_data_sha256,
+    sizeof(commit_data_sha256),
+};
+
+/*
+ * tree == dff2da90b254e1beb889d1f1f1288be1803782df (sha1)
+ * 34a4854b5426f92460b4ae35e6d79746be66c38bffd6ef3bc4f053ed78a36ba4 (sha256)
+ */
 static unsigned char tree_bytes[] = {
     0x78, 0x01, 0x2b, 0x29, 0x4a, 0x4d, 0x55, 0x30,
     0x34, 0x32, 0x63, 0x30, 0x34, 0x30, 0x30, 0x33,
@@ -163,10 +284,74 @@ static unsigned char tree_data[] = {
     0xd8, 0xc2, 0xe4, 0x8c, 0x53, 0x91,
 };
 
+static unsigned char tree_bytes_sha256[] = {
+    0x78, 0x01, 0x2b, 0x29, 0x4a, 0x4d, 0x55, 0x30,
+    0x32, 0x32, 0x66, 0x30, 0x34, 0x30, 0x30, 0x33,
+    0x31, 0x51, 0xc8, 0x48, 0xcd, 0xc9, 0xc9, 0xd7,
+    0x2b, 0xa9, 0x28, 0x61, 0x28, 0x65, 0x3b, 0x7d,
+    0xde, 0x27, 0x5c, 0xfb, 0xe5, 0x83, 0x2c, 0xf9,
+    0xb7, 0xa6, 0x6b, 0xa2, 0x65, 0x7f, 0x6c, 0x5d,
+    0xee, 0xab, 0x76, 0xa0, 0x9e, 0x49, 0xcd, 0xe3,
+    0xe9, 0xcd, 0xa8, 0xf9, 0xf9, 0x5a, 0x50, 0x0d,
+    0xf9, 0x79, 0xa9, 0x0c, 0x3e, 0xbc, 0x41, 0x17,
+    0x1b, 0x8e, 0xc9, 0x32, 0x9e, 0x93, 0x9a, 0x78,
+    0xef, 0xe8, 0xbb, 0x88, 0x0f, 0xa7, 0x9f, 0xc5,
+    0x5f, 0x9d, 0x62, 0xbc, 0x6e, 0x05, 0xf3, 0xea,
+    0x49, 0x95, 0xa9, 0x9e, 0xf6, 0xd7, 0xa1, 0x4a,
+    0x8b, 0xf3, 0x73, 0x53, 0x19, 0x38, 0x6c, 0xb4,
+    0xbb, 0x5d, 0xc2, 0x1c, 0x2e, 0x16, 0x3e, 0x5f,
+    0x95, 0x56, 0xcd, 0x6d, 0xc4, 0x50, 0xc0, 0xf6,
+    0xbd, 0xad, 0x50, 0xc0, 0xe8, 0xf5, 0x0e, 0x4d,
+    0xc3, 0x33, 0xcb, 0xe6, 0x1c, 0x8c, 0x86, 0xaa,
+    0x2d, 0x29, 0xcf, 0x67, 0xf8, 0x91, 0x14, 0xe7,
+    0xfc, 0xf3, 0x81, 0xbf, 0x8a, 0xa6, 0x7c, 0xf9,
+    0xd9, 0x7d, 0x3e, 0x85, 0x9b, 0x0f, 0x2d, 0xde,
+    0xc0, 0x60, 0x9f, 0xe0, 0x38, 0xdb, 0xee, 0x42,
+    0x16, 0x6b, 0x6f, 0x59, 0x4e, 0x37, 0x54, 0x69,
+    0x55, 0x6a, 0x51, 0x3e, 0x83, 0xcb, 0xbc, 0xd9,
+    0x95, 0x21, 0x0a, 0x67, 0xc5, 0xfe, 0x25, 0xac,
+    0x0d, 0x9a, 0x71, 0x3e, 0x83, 0x5f, 0x74, 0xf9,
+    0x59, 0xad, 0x93, 0x5b, 0xbc, 0x6e, 0x7d, 0x7f,
+    0x6b, 0x77, 0x87, 0x97, 0xe3, 0x6e, 0x05, 0x00,
+    0xba, 0xd1, 0x5f, 0x75
+};
+
+static unsigned char tree_data_sha256[] = {
+    0x31, 0x30, 0x30, 0x36, 0x34, 0x34, 0x20, 0x68,
+    0x65, 0x6c, 0x6c, 0x6f, 0x2e, 0x74, 0x78, 0x74,
+    0x00, 0x75, 0x06, 0xcb, 0xcf, 0x4c, 0x57, 0x2b,
+    0xe9, 0xe0, 0x6a, 0x1f, 0xed, 0x35, 0xac, 0x5b,
+    0x1d, 0xf8, 0xb5, 0xa7, 0x4d, 0x26, 0xc0, 0x7f,
+    0x02, 0x26, 0x48, 0xe5, 0xd9, 0x5a, 0x9f, 0x6f,
+    0x2a, 0x31, 0x30, 0x30, 0x36, 0x34, 0x34, 0x20,
+    0x6f, 0x6e, 0x65, 0x00, 0x4c, 0x0d, 0x52, 0xd1,
+    0x80, 0xc6, 0x1d, 0x01, 0xce, 0x1a, 0x91, 0xde,
+    0xc5, 0xee, 0x58, 0xf0, 0xcb, 0xe6, 0x5f, 0xd5,
+    0x94, 0x33, 0xae, 0xa8, 0x03, 0xab, 0x92, 0x79,
+    0x65, 0x49, 0x3f, 0xd7, 0x31, 0x30, 0x30, 0x36,
+    0x34, 0x34, 0x20, 0x73, 0x6f, 0x6d, 0x65, 0x00,
+    0x08, 0x3c, 0x2b, 0x8b, 0x44, 0x56, 0x40, 0xd1,
+    0x71, 0xe7, 0xaa, 0x66, 0x7b, 0x0b, 0x32, 0x00,
+    0x70, 0x06, 0xf7, 0x86, 0x71, 0x10, 0x32, 0xeb,
+    0xb8, 0x29, 0x31, 0xcc, 0xa6, 0x9c, 0xc1, 0x5b,
+    0x31, 0x30, 0x30, 0x36, 0x34, 0x34, 0x20, 0x74,
+    0x77, 0x6f, 0x00, 0xf8, 0x62, 0x5e, 0x43, 0xf9,
+    0xe0, 0x4f, 0x24, 0x29, 0x1f, 0x77, 0xcd, 0xbe,
+    0x4c, 0x71, 0xb3, 0xc2, 0xa3, 0xb0, 0x00, 0x3f,
+    0x60, 0x41, 0x9b, 0x3e, 0xd0, 0x6a, 0x05, 0x8d,
+    0x76, 0x6c, 0x8b, 0x31, 0x30, 0x30, 0x36, 0x34,
+    0x34, 0x20, 0x7a, 0x65, 0x72, 0x6f, 0x00, 0x44,
+    0x9e, 0x9b, 0x79, 0x54, 0x20, 0xcd, 0x16, 0xfe,
+    0x60, 0xad, 0x52, 0x98, 0xcf, 0x68, 0x0f, 0x15,
+    0xa7, 0xcd, 0x2a, 0xc9, 0xb4, 0x4a, 0xda, 0xf7,
+    0xed, 0x3e, 0xdc, 0x0d, 0x08, 0xdd, 0x78
+};
+
 static object_data tree = {
     tree_bytes,
     sizeof(tree_bytes),
     "dff2da90b254e1beb889d1f1f1288be1803782df",
+    GIT_OID_SHA1,
     "tree",
     "test-objects/df",
     "test-objects/df/f2da90b254e1beb889d1f1f1288be1803782df",
@@ -174,7 +359,22 @@ static object_data tree = {
     sizeof(tree_data),
 };
 
-/* tag == 09d373e1dfdc16b129ceec6dd649739911541e05 */
+static object_data tree_sha256 = {
+    tree_bytes_sha256,
+    sizeof(tree_bytes_sha256),
+    "34a4854b5426f92460b4ae35e6d79746be66c38bffd6ef3bc4f053ed78a36ba4",
+    GIT_OID_SHA256,
+    "tree",
+    "test-objects/34",
+    "test-objects/34/a4854b5426f92460b4ae35e6d79746be66c38bffd6ef3bc4f053ed78a36ba4",
+    tree_data_sha256,
+    sizeof(tree_data_sha256),
+};
+
+/*
+ * tag == 09d373e1dfdc16b129ceec6dd649739911541e05 (sha1)
+ * f535d7595d5d0e5e530b5deb34542c96491fea300a1318036b605306548cb225 (sha256)
+ */
 static unsigned char tag_bytes[] = {
     0x78, 0x01, 0x35, 0x4e, 0xcb, 0x0a, 0xc2, 0x40,
     0x10, 0xf3, 0xbc, 0x5f, 0x31, 0x77, 0xa1, 0xec,
@@ -222,10 +422,99 @@ static unsigned char tag_data[] = {
     0x2e, 0x30, 0x2e, 0x31, 0x0a,
 };
 
+static unsigned char tag_bytes_sha256[] = {
+    0x78, 0x01, 0x55, 0x8f, 0xd1, 0x4e, 0x84, 0x30,
+    0x10, 0x45, 0x7d, 0xee, 0x57, 0xcc, 0xbb, 0x2e,
+    0x81, 0x16, 0x68, 0x31, 0x1b, 0xa3, 0xf1, 0xd9,
+    0xf8, 0xe0, 0xfa, 0x01, 0x43, 0x99, 0x42, 0x0d,
+    0xb4, 0xa4, 0x14, 0xb3, 0xfc, 0xbd, 0xc5, 0xdd,
+    0x4d, 0xb4, 0x69, 0xd2, 0x9b, 0xc9, 0xdc, 0x7b,
+    0x6e, 0x23, 0xf6, 0x20, 0xa4, 0xba, 0xf3, 0xed,
+    0x17, 0xe9, 0x08, 0xc8, 0xb1, 0x14, 0xb9, 0x69,
+    0x6b, 0xd1, 0xf2, 0xa6, 0x34, 0xaa, 0x56, 0x68,
+    0x4a, 0x32, 0xb5, 0xd6, 0xba, 0xd1, 0x82, 0x14,
+    0xaf, 0x6a, 0x12, 0x32, 0x57, 0x55, 0xa3, 0xa9,
+    0x92, 0x0a, 0xb9, 0x50, 0x42, 0xa2, 0x56, 0x95,
+    0x10, 0xd2, 0x54, 0x35, 0x67, 0x71, 0x9b, 0x09,
+    0xb4, 0x9f, 0x26, 0x1b, 0x59, 0x4c, 0xd9, 0xdf,
+    0x79, 0x96, 0x67, 0xc5, 0x2e, 0x7b, 0x0a, 0xf0,
+    0x0a, 0xef, 0xf0, 0x66, 0x63, 0x4c, 0xf2, 0x78,
+    0x59, 0x4a, 0xf2, 0x99, 0xce, 0x38, 0xcd, 0x23,
+    0x65, 0x69, 0xf2, 0x04, 0x05, 0xe7, 0x52, 0x15,
+    0x25, 0x6f, 0x24, 0xdc, 0xe7, 0xe9, 0x30, 0x76,
+    0x1a, 0xec, 0x02, 0xe9, 0xc6, 0x81, 0x60, 0x8f,
+    0xbc, 0x56, 0x35, 0x3e, 0x40, 0xa0, 0x91, 0x70,
+    0xa1, 0x1b, 0xe5, 0x0a, 0x86, 0x65, 0x9d, 0x26,
+    0x0c, 0xdb, 0x6e, 0x25, 0x68, 0x7d, 0xb7, 0x81,
+    0x37, 0xbf, 0xf6, 0x0b, 0x13, 0x26, 0x5a, 0x16,
+    0xec, 0xe9, 0x21, 0xed, 0xbb, 0x88, 0xd6, 0x59,
+    0xd7, 0x83, 0x59, 0x43, 0x02, 0x04, 0xa0, 0xf3,
+    0x3c, 0xa2, 0xc3, 0x68, 0xbd, 0x63, 0x57, 0xd7,
+    0xbc, 0x86, 0xd9, 0x27, 0xca, 0x2d, 0x64, 0x40,
+    0xd7, 0x53, 0xaa, 0xe4, 0x62, 0xf0, 0xdd, 0xaa,
+    0xa9, 0x83, 0x76, 0xfb, 0x13, 0x9f, 0x31, 0xf6,
+    0x61, 0x7b, 0x47, 0xdd, 0xc1, 0x9b, 0x43, 0xbb,
+    0x3d, 0xc2, 0x0b, 0x7c, 0xc2, 0x69, 0x48, 0x75,
+    0x8f, 0xb8, 0xc6, 0xf4, 0xfe, 0xfb, 0x30, 0xfb,
+    0x01, 0xc9, 0x32, 0x7d, 0xbb
+};
+
+static unsigned char tag_data_sha256[] = {
+    0x6f, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x20, 0x61,
+    0x32, 0x61, 0x34, 0x33, 0x30, 0x66, 0x62, 0x36,
+    0x33, 0x62, 0x32, 0x39, 0x34, 0x66, 0x38, 0x36,
+    0x38, 0x61, 0x66, 0x34, 0x65, 0x66, 0x36, 0x63,
+    0x63, 0x63, 0x39, 0x63, 0x33, 0x65, 0x38, 0x32,
+    0x35, 0x36, 0x65, 0x33, 0x37, 0x30, 0x38, 0x35,
+    0x39, 0x63, 0x65, 0x35, 0x37, 0x38, 0x61, 0x32,
+    0x33, 0x38, 0x33, 0x37, 0x61, 0x63, 0x38, 0x35,
+    0x33, 0x33, 0x37, 0x66, 0x35, 0x36, 0x32, 0x0a,
+    0x74, 0x79, 0x70, 0x65, 0x20, 0x63, 0x6f, 0x6d,
+    0x6d, 0x69, 0x74, 0x0a, 0x74, 0x61, 0x67, 0x20,
+    0x76, 0x30, 0x2e, 0x30, 0x2e, 0x31, 0x0a, 0x74,
+    0x61, 0x67, 0x67, 0x65, 0x72, 0x20, 0x43, 0x20,
+    0x4f, 0x20, 0x4d, 0x69, 0x74, 0x74, 0x65, 0x72,
+    0x20, 0x3c, 0x63, 0x6f, 0x6d, 0x6d, 0x69, 0x74,
+    0x74, 0x65, 0x72, 0x40, 0x65, 0x78, 0x61, 0x6d,
+    0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d, 0x3e,
+    0x20, 0x31, 0x32, 0x32, 0x37, 0x38, 0x31, 0x34,
+    0x32, 0x39, 0x37, 0x20, 0x2b, 0x30, 0x30, 0x30,
+    0x30, 0x0a, 0x0a, 0x54, 0x68, 0x69, 0x73, 0x20,
+    0x69, 0x73, 0x20, 0x74, 0x68, 0x65, 0x20, 0x74,
+    0x61, 0x67, 0x20, 0x6f, 0x62, 0x6a, 0x65, 0x63,
+    0x74, 0x20, 0x66, 0x6f, 0x72, 0x20, 0x72, 0x65,
+    0x6c, 0x65, 0x61, 0x73, 0x65, 0x20, 0x76, 0x30,
+    0x2e, 0x30, 0x2e, 0x31, 0x0a, 0x20, 0x63, 0x6f,
+    0x6d, 0x6d, 0x69, 0x74, 0x20, 0x73, 0x75, 0x6d,
+    0x6d, 0x61, 0x72, 0x79, 0x0a, 0x0a, 0x54, 0x68,
+    0x65, 0x20, 0x62, 0x6f, 0x64, 0x79, 0x20, 0x6f,
+    0x66, 0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6f,
+    0x6d, 0x6d, 0x69, 0x74, 0x20, 0x6d, 0x65, 0x73,
+    0x73, 0x61, 0x67, 0x65, 0x2c, 0x20, 0x63, 0x6f,
+    0x6e, 0x74, 0x61, 0x69, 0x6e, 0x69, 0x6e, 0x67,
+    0x20, 0x66, 0x75, 0x72, 0x74, 0x68, 0x65, 0x72,
+    0x20, 0x65, 0x78, 0x70, 0x6c, 0x61, 0x6e, 0x61,
+    0x74, 0x69, 0x6f, 0x6e, 0x0a, 0x6f, 0x66, 0x20,
+    0x74, 0x68, 0x65, 0x20, 0x70, 0x75, 0x72, 0x70,
+    0x6f, 0x73, 0x65, 0x20, 0x6f, 0x66, 0x20, 0x74,
+    0x68, 0x65, 0x20, 0x63, 0x68, 0x61, 0x6e, 0x67,
+    0x65, 0x73, 0x20, 0x69, 0x6e, 0x74, 0x72, 0x6f,
+    0x64, 0x75, 0x63, 0x65, 0x64, 0x20, 0x62, 0x79,
+    0x20, 0x74, 0x68, 0x65, 0x20, 0x63, 0x6f, 0x6d,
+    0x6d, 0x69, 0x74, 0x2e, 0x0a, 0x0a, 0x53, 0x69,
+    0x67, 0x6e, 0x65, 0x64, 0x2d, 0x6f, 0x66, 0x2d,
+    0x62, 0x79, 0x3a, 0x20, 0x41, 0x20, 0x55, 0x20,
+    0x54, 0x68, 0x6f, 0x72, 0x20, 0x3c, 0x61, 0x75,
+    0x74, 0x68, 0x6f, 0x72, 0x40, 0x65, 0x78, 0x61,
+    0x6d, 0x70, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d,
+    0x3e, 0x0a
+};
+
 static object_data tag = {
     tag_bytes,
     sizeof(tag_bytes),
     "09d373e1dfdc16b129ceec6dd649739911541e05",
+    GIT_OID_SHA1,
     "tag",
     "test-objects/09",
     "test-objects/09/d373e1dfdc16b129ceec6dd649739911541e05",
@@ -233,7 +522,22 @@ static object_data tag = {
     sizeof(tag_data),
 };
 
-/* zero == e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 */
+static object_data tag_sha256 = {
+    tag_bytes_sha256,
+    sizeof(tag_bytes_sha256),
+    "f535d7595d5d0e5e530b5deb34542c96491fea300a1318036b605306548cb225",
+    GIT_OID_SHA256,
+    "tag",
+    "test-objects/f5",
+    "test-objects/f5/35d7595d5d0e5e530b5deb34542c96491fea300a1318036b605306548cb225",
+    tag_data_sha256,
+    sizeof(tag_data_sha256),
+};
+
+/*
+ * zero == e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 (sha1)
+ * 473a0f4c3be8a93681a267e3b1e9a7dcda1185436fe141f7749120a303721813 (sha256)
+ */
 static unsigned char zero_bytes[] = {
     0x78, 0x01, 0x4b, 0xca, 0xc9, 0x4f, 0x52, 0x30,
     0x60, 0x00, 0x00, 0x09, 0xb0, 0x01, 0xf0,
@@ -247,6 +551,7 @@ static object_data zero = {
     zero_bytes,
     sizeof(zero_bytes),
     "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391",
+    GIT_OID_SHA1,
     "blob",
     "test-objects/e6",
     "test-objects/e6/9de29bb2d1d6434b8b29ae775ad8c2e48c5391",
@@ -254,7 +559,22 @@ static object_data zero = {
     0,
 };
 
-/* two == 78981922613b2afb6025042ff6bd878ac1994e85 */
+static object_data zero_sha256 = {
+    zero_bytes,
+    sizeof(zero_bytes),
+    "473a0f4c3be8a93681a267e3b1e9a7dcda1185436fe141f7749120a303721813",
+    GIT_OID_SHA256,
+    "blob",
+    "test-objects/47",
+    "test-objects/47/3a0f4c3be8a93681a267e3b1e9a7dcda1185436fe141f7749120a303721813",
+    zero_data,
+    0,
+};
+
+/*
+ * two == 78981922613b2afb6025042ff6bd878ac1994e85 (sha1)
+ * f8625e43f9e04f24291f77cdbe4c71b3c2a3b0003f60419b3ed06a058d766c8b (sha256)
+ */
 static unsigned char two_bytes[] = {
     0x78, 0x01, 0x4b, 0xca, 0xc9, 0x4f, 0x52, 0x30,
     0x62, 0x48, 0xe4, 0x02, 0x00, 0x0e, 0x64, 0x02,
@@ -269,6 +589,7 @@ static object_data two = {
     two_bytes,
     sizeof(two_bytes),
     "78981922613b2afb6025042ff6bd878ac1994e85",
+    GIT_OID_SHA1,
     "blob",
     "test-objects/78",
     "test-objects/78/981922613b2afb6025042ff6bd878ac1994e85",
@@ -276,7 +597,22 @@ static object_data two = {
     sizeof(two_data),
 };
 
-/* some == fd8430bc864cfcd5f10e5590f8a447e01b942bfe */
+static object_data two_sha256 = {
+    two_bytes,
+    sizeof(two_bytes),
+    "f8625e43f9e04f24291f77cdbe4c71b3c2a3b0003f60419b3ed06a058d766c8b",
+    GIT_OID_SHA256,
+    "blob",
+    "test-objects/f8",
+    "test-objects/f8/625e43f9e04f24291f77cdbe4c71b3c2a3b0003f60419b3ed06a058d766c8b",
+    two_data,
+    sizeof(two_data),
+};
+
+/*
+ * some == fd8430bc864cfcd5f10e5590f8a447e01b942bfe (sha1)
+ * 083c2b8b445640d171e7aa667b0b32007006f786711032ebb82931cca69cc15b (sha256)
+ */
 static unsigned char some_bytes[] = {
     0x78, 0x01, 0x7d, 0x54, 0xc1, 0x4e, 0xe3, 0x30,
     0x10, 0xdd, 0x33, 0x5f, 0x31, 0xc7, 0x5d, 0x94,
@@ -514,9 +850,22 @@ static object_data some = {
     some_bytes,
     sizeof(some_bytes),
     "fd8430bc864cfcd5f10e5590f8a447e01b942bfe",
+    GIT_OID_SHA1,
     "blob",
     "test-objects/fd",
     "test-objects/fd/8430bc864cfcd5f10e5590f8a447e01b942bfe",
     some_data,
     sizeof(some_data),
 };
+
+static object_data some_sha256 = {
+    some_bytes,
+    sizeof(some_bytes),
+    "083c2b8b445640d171e7aa667b0b32007006f786711032ebb82931cca69cc15b",
+    GIT_OID_SHA256,
+    "blob",
+    "test-objects/08",
+    "test-objects/08/3c2b8b445640d171e7aa667b0b32007006f786711032ebb82931cca69cc15b",
+    some_data,
+    sizeof(some_data),
+};