refactor: `src` is now `src/libgit2`

1 files changed, 601 insertions, 0 deletions

diff --git a/src/libgit2/object.c b/src/libgit2/object.c
new file mode 100644
index 000000000..7bc256fce
--- /dev/null
+++ b/src/libgit2/object.c
@@ -0,0 +1,601 @@
+/*
+ * 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 "object.h"
+
+#include "git2/object.h"
+
+#include "repository.h"
+
+#include "buf.h"
+#include "commit.h"
+#include "hash.h"
+#include "tree.h"
+#include "blob.h"
+#include "oid.h"
+#include "tag.h"
+
+bool git_object__strict_input_validation = true;
+
+extern int git_odb_hash(git_oid *out, const void *data, size_t len, git_object_t type);
+size_t git_object__size(git_object_t type);
+
+typedef struct {
+	const char	*str;	/* type name string */
+	size_t		size;	/* size in bytes of the object structure */
+
+	int  (*parse)(void *self, git_odb_object *obj);
+	int  (*parse_raw)(void *self, const char *data, size_t size);
+	void (*free)(void *self);
+} git_object_def;
+
+static git_object_def git_objects_table[] = {
+	/* 0 = GIT_OBJECT__EXT1 */
+	{ "", 0, NULL, NULL, NULL },
+
+	/* 1 = GIT_OBJECT_COMMIT */
+	{ "commit", sizeof(git_commit), git_commit__parse, git_commit__parse_raw, git_commit__free },
+
+	/* 2 = GIT_OBJECT_TREE */
+	{ "tree", sizeof(git_tree), git_tree__parse, git_tree__parse_raw, git_tree__free },
+
+	/* 3 = GIT_OBJECT_BLOB */
+	{ "blob", sizeof(git_blob), git_blob__parse, git_blob__parse_raw, git_blob__free },
+
+	/* 4 = GIT_OBJECT_TAG */
+	{ "tag", sizeof(git_tag), git_tag__parse, git_tag__parse_raw, git_tag__free },
+
+	/* 5 = GIT_OBJECT__EXT2 */
+	{ "", 0, NULL, NULL, NULL },
+	/* 6 = GIT_OBJECT_OFS_DELTA */
+	{ "OFS_DELTA", 0, NULL, NULL, NULL },
+	/* 7 = GIT_OBJECT_REF_DELTA */
+	{ "REF_DELTA", 0, NULL, NULL, NULL },
+};
+
+int git_object__from_raw(
+	git_object **object_out,
+	const char *data,
+	size_t size,
+	git_object_t type)
+{
+	git_object_def *def;
+	git_object *object;
+	size_t object_size;
+	int error;
+
+	GIT_ASSERT_ARG(object_out);
+	*object_out = NULL;
+
+	/* Validate type match */
+	if (type != GIT_OBJECT_BLOB && type != GIT_OBJECT_TREE && type != GIT_OBJECT_COMMIT && type != GIT_OBJECT_TAG) {
+		git_error_set(GIT_ERROR_INVALID, "the requested type is invalid");
+		return GIT_ENOTFOUND;
+	}
+
+	if ((object_size = git_object__size(type)) == 0) {
+		git_error_set(GIT_ERROR_INVALID, "the requested type is invalid");
+		return GIT_ENOTFOUND;
+	}
+
+	/* Allocate and initialize base object */
+	object = git__calloc(1, object_size);
+	GIT_ERROR_CHECK_ALLOC(object);
+	object->cached.flags = GIT_CACHE_STORE_PARSED;
+	object->cached.type = type;
+	if ((error = git_odb_hash(&object->cached.oid, data, size, type)) < 0)
+		return error;
+
+	/* Parse raw object data */
+	def = &git_objects_table[type];
+	GIT_ASSERT(def->free && def->parse_raw);
+
+	if ((error = def->parse_raw(object, data, size)) < 0) {
+		def->free(object);
+		return error;
+	}
+
+	git_cached_obj_incref(object);
+	*object_out = object;
+
+	return 0;
+}
+
+int git_object__from_odb_object(
+	git_object **object_out,
+	git_repository *repo,
+	git_odb_object *odb_obj,
+	git_object_t type)
+{
+	int error;
+	size_t object_size;
+	git_object_def *def;
+	git_object *object = NULL;
+
+	GIT_ASSERT_ARG(object_out);
+	*object_out = NULL;
+
+	/* Validate type match */
+	if (type != GIT_OBJECT_ANY && type != odb_obj->cached.type) {
+		git_error_set(GIT_ERROR_INVALID,
+			"the requested type does not match the type in the ODB");
+		return GIT_ENOTFOUND;
+	}
+
+	if ((object_size = git_object__size(odb_obj->cached.type)) == 0) {
+		git_error_set(GIT_ERROR_INVALID, "the requested type is invalid");
+		return GIT_ENOTFOUND;
+	}
+
+	/* Allocate and initialize base object */
+	object = git__calloc(1, object_size);
+	GIT_ERROR_CHECK_ALLOC(object);
+
+	git_oid_cpy(&object->cached.oid, &odb_obj->cached.oid);
+	object->cached.type = odb_obj->cached.type;
+	object->cached.size = odb_obj->cached.size;
+	object->repo = repo;
+
+	/* Parse raw object data */
+	def = &git_objects_table[odb_obj->cached.type];
+	GIT_ASSERT(def->free && def->parse);
+
+	if ((error = def->parse(object, odb_obj)) < 0) {
+		/*
+		 * parse returns EINVALID on invalid data; downgrade
+		 * that to a normal -1 error code.
+		 */
+		def->free(object);
+		return -1;
+	}
+
+	*object_out = git_cache_store_parsed(&repo->objects, object);
+	return 0;
+}
+
+void git_object__free(void *obj)
+{
+	git_object_t type = ((git_object *)obj)->cached.type;
+
+	if (type < 0 || ((size_t)type) >= ARRAY_SIZE(git_objects_table) ||
+		!git_objects_table[type].free)
+		git__free(obj);
+	else
+		git_objects_table[type].free(obj);
+}
+
+int git_object_lookup_prefix(
+	git_object **object_out,
+	git_repository *repo,
+	const git_oid *id,
+	size_t len,
+	git_object_t type)
+{
+	git_object *object = NULL;
+	git_odb *odb = NULL;
+	git_odb_object *odb_obj = NULL;
+	int error = 0;
+
+	GIT_ASSERT_ARG(repo);
+	GIT_ASSERT_ARG(object_out);
+	GIT_ASSERT_ARG(id);
+
+	if (len < GIT_OID_MINPREFIXLEN) {
+		git_error_set(GIT_ERROR_OBJECT, "ambiguous lookup - OID prefix is too short");
+		return GIT_EAMBIGUOUS;
+	}
+
+	error = git_repository_odb__weakptr(&odb, repo);
+	if (error < 0)
+		return error;
+
+	if (len > GIT_OID_HEXSZ)
+		len = GIT_OID_HEXSZ;
+
+	if (len == GIT_OID_HEXSZ) {
+		git_cached_obj *cached = NULL;
+
+		/* We want to match the full id : we can first look up in the cache,
+		 * since there is no need to check for non ambiguousity
+		 */
+		cached = git_cache_get_any(&repo->objects, id);
+		if (cached != NULL) {
+			if (cached->flags == GIT_CACHE_STORE_PARSED) {
+				object = (git_object *)cached;
+
+				if (type != GIT_OBJECT_ANY && type != object->cached.type) {
+					git_object_free(object);
+					git_error_set(GIT_ERROR_INVALID,
+						"the requested type does not match the type in the ODB");
+					return GIT_ENOTFOUND;
+				}
+
+				*object_out = object;
+				return 0;
+			} else if (cached->flags == GIT_CACHE_STORE_RAW) {
+				odb_obj = (git_odb_object *)cached;
+			} else {
+				GIT_ASSERT(!"Wrong caching type in the global object cache");
+			}
+		} else {
+			/* Object was not found in the cache, let's explore the backends.
+			 * We could just use git_odb_read_unique_short_oid,
+			 * it is the same cost for packed and loose object backends,
+			 * but it may be much more costly for sqlite and hiredis.
+			 */
+			error = git_odb_read(&odb_obj, odb, id);
+		}
+	} else {
+		git_oid short_oid = {{ 0 }};
+
+		git_oid__cpy_prefix(&short_oid, id, len);
+
+		/* If len < GIT_OID_HEXSZ (a strict short oid was given), we have
+		 * 2 options :
+		 * - We always search in the cache first. If we find that short oid is
+		 *	ambiguous, we can stop. But in all the other cases, we must then
+		 *	explore all the backends (to find an object if there was match,
+		 *	or to check that oid is not ambiguous if we have found 1 match in
+		 *	the cache)
+		 * - We never explore the cache, go right to exploring the backends
+		 * We chose the latter : we explore directly the backends.
+		 */
+		error = git_odb_read_prefix(&odb_obj, odb, &short_oid, len);
+	}
+
+	if (error < 0)
+		return error;
+
+	error = git_object__from_odb_object(object_out, repo, odb_obj, type);
+
+	git_odb_object_free(odb_obj);
+
+	return error;
+}
+
+int git_object_lookup(git_object **object_out, git_repository *repo, const git_oid *id, git_object_t type) {
+	return git_object_lookup_prefix(object_out, repo, id, GIT_OID_HEXSZ, type);
+}
+
+void git_object_free(git_object *object)
+{
+	if (object == NULL)
+		return;
+
+	git_cached_obj_decref(object);
+}
+
+const git_oid *git_object_id(const git_object *obj)
+{
+	GIT_ASSERT_ARG_WITH_RETVAL(obj, NULL);
+	return &obj->cached.oid;
+}
+
+git_object_t git_object_type(const git_object *obj)
+{
+	GIT_ASSERT_ARG_WITH_RETVAL(obj, GIT_OBJECT_INVALID);
+	return obj->cached.type;
+}
+
+git_repository *git_object_owner(const git_object *obj)
+{
+	GIT_ASSERT_ARG_WITH_RETVAL(obj, NULL);
+	return obj->repo;
+}
+
+const char *git_object_type2string(git_object_t type)
+{
+	if (type < 0 || ((size_t) type) >= ARRAY_SIZE(git_objects_table))
+		return "";
+
+	return git_objects_table[type].str;
+}
+
+git_object_t git_object_string2type(const char *str)
+{
+	if (!str)
+		return GIT_OBJECT_INVALID;
+
+	return git_object_stringn2type(str, strlen(str));
+}
+
+git_object_t git_object_stringn2type(const char *str, size_t len)
+{
+	size_t i;
+
+	if (!str || !len || !*str)
+		return GIT_OBJECT_INVALID;
+
+	for (i = 0; i < ARRAY_SIZE(git_objects_table); i++)
+		if (*git_objects_table[i].str &&
+			!git__prefixncmp(str, len, git_objects_table[i].str))
+			return (git_object_t)i;
+
+	return GIT_OBJECT_INVALID;
+}
+
+int git_object_typeisloose(git_object_t type)
+{
+	if (type < 0 || ((size_t) type) >= ARRAY_SIZE(git_objects_table))
+		return 0;
+
+	return (git_objects_table[type].size > 0) ? 1 : 0;
+}
+
+size_t git_object__size(git_object_t type)
+{
+	if (type < 0 || ((size_t) type) >= ARRAY_SIZE(git_objects_table))
+		return 0;
+
+	return git_objects_table[type].size;
+}
+
+static int dereference_object(git_object **dereferenced, git_object *obj)
+{
+	git_object_t type = git_object_type(obj);
+
+	switch (type) {
+	case GIT_OBJECT_COMMIT:
+		return git_commit_tree((git_tree **)dereferenced, (git_commit*)obj);
+
+	case GIT_OBJECT_TAG:
+		return git_tag_target(dereferenced, (git_tag*)obj);
+
+	case GIT_OBJECT_BLOB:
+	case GIT_OBJECT_TREE:
+		return GIT_EPEEL;
+
+	default:
+		return GIT_EINVALIDSPEC;
+	}
+}
+
+static int peel_error(int error, const git_oid *oid, git_object_t type)
+{
+	const char *type_name;
+	char hex_oid[GIT_OID_HEXSZ + 1];
+
+	type_name = git_object_type2string(type);
+
+	git_oid_fmt(hex_oid, oid);
+	hex_oid[GIT_OID_HEXSZ] = '\0';
+
+	git_error_set(GIT_ERROR_OBJECT, "the git_object of id '%s' can not be "
+		"successfully peeled into a %s (git_object_t=%i).", hex_oid, type_name, type);
+
+	return error;
+}
+
+static int check_type_combination(git_object_t type, git_object_t target)
+{
+	if (type == target)
+		return 0;
+
+	switch (type) {
+	case GIT_OBJECT_BLOB:
+	case GIT_OBJECT_TREE:
+		/* a blob or tree can never be peeled to anything but themselves */
+		return GIT_EINVALIDSPEC;
+		break;
+	case GIT_OBJECT_COMMIT:
+		/* a commit can only be peeled to a tree */
+		if (target != GIT_OBJECT_TREE && target != GIT_OBJECT_ANY)
+			return GIT_EINVALIDSPEC;
+		break;
+	case GIT_OBJECT_TAG:
+		/* a tag may point to anything, so we let anything through */
+		break;
+	default:
+		return GIT_EINVALIDSPEC;
+	}
+
+	return 0;
+}
+
+int git_object_peel(
+	git_object **peeled,
+	const git_object *object,
+	git_object_t target_type)
+{
+	git_object *source, *deref = NULL;
+	int error;
+
+	GIT_ASSERT_ARG(object);
+	GIT_ASSERT_ARG(peeled);
+
+	GIT_ASSERT_ARG(target_type == GIT_OBJECT_TAG ||
+		target_type == GIT_OBJECT_COMMIT ||
+		target_type == GIT_OBJECT_TREE ||
+		target_type == GIT_OBJECT_BLOB ||
+		target_type == GIT_OBJECT_ANY);
+
+	if ((error = check_type_combination(git_object_type(object), target_type)) < 0)
+		return peel_error(error, git_object_id(object), target_type);
+
+	if (git_object_type(object) == target_type)
+		return git_object_dup(peeled, (git_object *)object);
+
+	source = (git_object *)object;
+
+	while (!(error = dereference_object(&deref, source))) {
+
+		if (source != object)
+			git_object_free(source);
+
+		if (git_object_type(deref) == target_type) {
+			*peeled = deref;
+			return 0;
+		}
+
+		if (target_type == GIT_OBJECT_ANY &&
+			git_object_type(deref) != git_object_type(object))
+		{
+			*peeled = deref;
+			return 0;
+		}
+
+		source = deref;
+		deref = NULL;
+	}
+
+	if (source != object)
+		git_object_free(source);
+
+	git_object_free(deref);
+
+	if (error)
+		error = peel_error(error, git_object_id(object), target_type);
+
+	return error;
+}
+
+int git_object_dup(git_object **dest, git_object *source)
+{
+	git_cached_obj_incref(source);
+	*dest = source;
+	return 0;
+}
+
+int git_object_lookup_bypath(
+		git_object **out,
+		const git_object *treeish,
+		const char *path,
+		git_object_t type)
+{
+	int error = -1;
+	git_tree *tree = NULL;
+	git_tree_entry *entry = NULL;
+
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(treeish);
+	GIT_ASSERT_ARG(path);
+
+	if ((error = git_object_peel((git_object**)&tree, treeish, GIT_OBJECT_TREE)) < 0 ||
+		 (error = git_tree_entry_bypath(&entry, tree, path)) < 0)
+	{
+		goto cleanup;
+	}
+
+	if (type != GIT_OBJECT_ANY && git_tree_entry_type(entry) != type)
+	{
+		git_error_set(GIT_ERROR_OBJECT,
+				"object at path '%s' is not of the asked-for type %d",
+				path, type);
+		error = GIT_EINVALIDSPEC;
+		goto cleanup;
+	}
+
+	error = git_tree_entry_to_object(out, git_object_owner(treeish), entry);
+
+cleanup:
+	git_tree_entry_free(entry);
+	git_tree_free(tree);
+	return error;
+}
+
+static int git_object__short_id(git_str *out, const git_object *obj)
+{
+	git_repository *repo;
+	int len = GIT_ABBREV_DEFAULT, error;
+	git_oid id = {{0}};
+	git_odb *odb;
+
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(obj);
+
+	repo = git_object_owner(obj);
+
+	if ((error = git_repository__configmap_lookup(&len, repo, GIT_CONFIGMAP_ABBREV)) < 0)
+		return error;
+
+	if ((error = git_repository_odb(&odb, repo)) < 0)
+		return error;
+
+	while (len < GIT_OID_HEXSZ) {
+		/* set up short oid */
+		memcpy(&id.id, &obj->cached.oid.id, (len + 1) / 2);
+		if (len & 1)
+			id.id[len / 2] &= 0xf0;
+
+		error = git_odb_exists_prefix(NULL, odb, &id, len);
+		if (error != GIT_EAMBIGUOUS)
+			break;
+
+		git_error_clear();
+		len++;
+	}
+
+	if (!error && !(error = git_str_grow(out, len + 1))) {
+		git_oid_tostr(out->ptr, len + 1, &id);
+		out->size = len;
+	}
+
+	git_odb_free(odb);
+
+	return error;
+}
+
+int git_object_short_id(git_buf *out, const git_object *obj)
+{
+	GIT_BUF_WRAP_PRIVATE(out, git_object__short_id, obj);
+}
+
+bool git_object__is_valid(
+	git_repository *repo, const git_oid *id, git_object_t expected_type)
+{
+	git_odb *odb;
+	git_object_t actual_type;
+	size_t len;
+	int error;
+
+	if (!git_object__strict_input_validation)
+		return true;
+
+	if ((error = git_repository_odb__weakptr(&odb, repo)) < 0 ||
+		(error = git_odb_read_header(&len, &actual_type, odb, id)) < 0)
+		return false;
+
+	if (expected_type != GIT_OBJECT_ANY && expected_type != actual_type) {
+		git_error_set(GIT_ERROR_INVALID,
+			"the requested type does not match the type in the ODB");
+		return false;
+	}
+
+	return true;
+}
+
+int git_object_rawcontent_is_valid(
+	int *valid,
+	const char *buf,
+	size_t len,
+	git_object_t type)
+{
+	git_object *obj = NULL;
+	int error;
+
+	GIT_ASSERT_ARG(valid);
+	GIT_ASSERT_ARG(buf);
+
+	/* Blobs are always valid; don't bother parsing. */
+	if (type == GIT_OBJECT_BLOB) {
+		*valid = 1;
+		return 0;
+	}
+
+	error = git_object__from_raw(&obj, buf, len, type);
+	git_object_free(obj);
+
+	if (error == 0) {
+		*valid = 1;
+		return 0;
+	} else if (error == GIT_EINVALID) {
+		*valid = 0;
+		return 0;
+	}
+
+	return error;
+}