include/aws/cryptosdk/private/utils.h

/*
 * Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"). You may not use
 * this file except in compliance with the License. A copy of the License is
 * located at
 *
 *     http://aws.amazon.com/apache2.0/
 *
 * or in the "license" file accompanying this file. This file is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied. See the License for the specific language governing permissions and
 * limitations under the License.
 */
#ifndef AWS_CRYPTOSDK_PRIVATE_UTILS_H
#define AWS_CRYPTOSDK_PRIVATE_UTILS_H

#include <aws/common/array_list.h>
#include <aws/common/hash_table.h>
#include <aws/common/string.h>

/**
 * Allocates array list and places all hash elements from map into it.
 * No guarantees are made about the order of elements.
 *
 * On failure, does not allocate any memory.
 */
int aws_cryptosdk_hash_elems_array_init(
    struct aws_allocator *alloc, struct aws_array_list *elems, const struct aws_hash_table *map);

/**
 * For sorting arrays of struct aws_hash_elements by doing string comparison on
 * keys. Comparator takes arguments that are (const struct aws_hash_element *) cast
 * to (const void *).
 *
 * This is a comparator function that can be used with aws_array_list_sort.
 */
int aws_cryptosdk_compare_hash_elems_by_key_string(const void *elem_a, const void *elem_b);

/**
 * An optimized version of aws_string_new_from_string. It makes a new copy of the
 * string except when the string was declared by AWS_STATIC_STRING_FROM_LITERAL,
 * in which case it returns a pointer to the same string. This is safe because
 * aws_string_destroy is a no-op for static strings.
 */
struct aws_string *aws_cryptosdk_string_dup(struct aws_allocator *alloc, const struct aws_string *str);
#endif  // AWS_CRYPTOSDK_PRIVATE_UTILS_H