1 files changed, 189 insertions, 0 deletions

diff --git a/src/libgit2/odb_mempack.c b/src/libgit2/odb_mempack.c
new file mode 100644
index 000000000..6f27f45f8
--- /dev/null
+++ b/src/libgit2/odb_mempack.c
@@ -0,0 +1,189 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include "common.h"
+
+#include "buf.h"
+#include "futils.h"
+#include "hash.h"
+#include "odb.h"
+#include "array.h"
+#include "oidmap.h"
+#include "pack-objects.h"
+
+#include "git2/odb_backend.h"
+#include "git2/object.h"
+#include "git2/types.h"
+#include "git2/pack.h"
+#include "git2/sys/odb_backend.h"
+#include "git2/sys/mempack.h"
+
+struct memobject {
+	git_oid oid;
+	size_t len;
+	git_object_t type;
+	char data[GIT_FLEX_ARRAY];
+};
+
+struct memory_packer_db {
+	git_odb_backend parent;
+	git_oidmap *objects;
+	git_array_t(struct memobject *) commits;
+};
+
+static int impl__write(git_odb_backend *_backend, const git_oid *oid, const void *data, size_t len, git_object_t type)
+{
+	struct memory_packer_db *db = (struct memory_packer_db *)_backend;
+	struct memobject *obj = NULL;
+	size_t alloc_len;
+
+	if (git_oidmap_exists(db->objects, oid))
+		return 0;
+
+	GIT_ERROR_CHECK_ALLOC_ADD(&alloc_len, sizeof(struct memobject), len);
+	obj = git__malloc(alloc_len);
+	GIT_ERROR_CHECK_ALLOC(obj);
+
+	memcpy(obj->data, data, len);
+	git_oid_cpy(&obj->oid, oid);
+	obj->len = len;
+	obj->type = type;
+
+	if (git_oidmap_set(db->objects, &obj->oid, obj) < 0)
+		return -1;
+
+	if (type == GIT_OBJECT_COMMIT) {
+		struct memobject **store = git_array_alloc(db->commits);
+		GIT_ERROR_CHECK_ALLOC(store);
+		*store = obj;
+	}
+
+	return 0;
+}
+
+static int impl__exists(git_odb_backend *backend, const git_oid *oid)
+{
+	struct memory_packer_db *db = (struct memory_packer_db *)backend;
+
+	return git_oidmap_exists(db->objects, oid);
+}
+
+static int impl__read(void **buffer_p, size_t *len_p, git_object_t *type_p, git_odb_backend *backend, const git_oid *oid)
+{
+	struct memory_packer_db *db = (struct memory_packer_db *)backend;
+	struct memobject *obj;
+
+	if ((obj = git_oidmap_get(db->objects, oid)) == NULL)
+		return GIT_ENOTFOUND;
+
+	*len_p = obj->len;
+	*type_p = obj->type;
+	*buffer_p = git__malloc(obj->len);
+	GIT_ERROR_CHECK_ALLOC(*buffer_p);
+
+	memcpy(*buffer_p, obj->data, obj->len);
+	return 0;
+}
+
+static int impl__read_header(size_t *len_p, git_object_t *type_p, git_odb_backend *backend, const git_oid *oid)
+{
+	struct memory_packer_db *db = (struct memory_packer_db *)backend;
+	struct memobject *obj;
+
+	if ((obj = git_oidmap_get(db->objects, oid)) == NULL)
+		return GIT_ENOTFOUND;
+
+	*len_p = obj->len;
+	*type_p = obj->type;
+	return 0;
+}
+
+static int git_mempack__dump(
+	git_str *pack,
+	git_repository *repo,
+	git_odb_backend *_backend)
+{
+	struct memory_packer_db *db = (struct memory_packer_db *)_backend;
+	git_packbuilder *packbuilder;
+	uint32_t i;
+	int err = -1;
+
+	if (git_packbuilder_new(&packbuilder, repo) < 0)
+		return -1;
+
+	git_packbuilder_set_threads(packbuilder, 0);
+
+	for (i = 0; i < db->commits.size; ++i) {
+		struct memobject *commit = db->commits.ptr[i];
+
+		err = git_packbuilder_insert_commit(packbuilder, &commit->oid);
+		if (err < 0)
+			goto cleanup;
+	}
+
+	err = git_packbuilder__write_buf(pack, packbuilder);
+
+cleanup:
+	git_packbuilder_free(packbuilder);
+	return err;
+}
+
+int git_mempack_dump(
+	git_buf *pack,
+	git_repository *repo,
+	git_odb_backend *_backend)
+{
+	GIT_BUF_WRAP_PRIVATE(pack, git_mempack__dump, repo, _backend);
+}
+
+int git_mempack_reset(git_odb_backend *_backend)
+{
+	struct memory_packer_db *db = (struct memory_packer_db *)_backend;
+	struct memobject *object = NULL;
+
+	git_oidmap_foreach_value(db->objects, object, {
+		git__free(object);
+	});
+
+	git_array_clear(db->commits);
+
+	git_oidmap_clear(db->objects);
+
+	return 0;
+}
+
+static void impl__free(git_odb_backend *_backend)
+{
+	struct memory_packer_db *db = (struct memory_packer_db *)_backend;
+
+	git_mempack_reset(_backend);
+	git_oidmap_free(db->objects);
+	git__free(db);
+}
+
+int git_mempack_new(git_odb_backend **out)
+{
+	struct memory_packer_db *db;
+
+	GIT_ASSERT_ARG(out);
+
+	db = git__calloc(1, sizeof(struct memory_packer_db));
+	GIT_ERROR_CHECK_ALLOC(db);
+
+	if (git_oidmap_new(&db->objects) < 0)
+		return -1;
+
+	db->parent.version = GIT_ODB_BACKEND_VERSION;
+	db->parent.read = &impl__read;
+	db->parent.write = &impl__write;
+	db->parent.read_header = &impl__read_header;
+	db->parent.exists = &impl__exists;
+	db->parent.free = &impl__free;
+
+	*out = (git_odb_backend *)db;
+	return 0;
+}