/*
 * Copyright (c) 2021 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License 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.
 */
/* [Standardize-exceptions] Use unsafe function: Portability
 * [reason] Use unsafe function to implement security function to maintain platform compatibility.
 *          And sufficient input validation is performed before calling
 */

#include "securecutil.h"

/*******************************************************************************
 * <FUNCTION DESCRIPTION>
 *   The wmemcpy_s function copies n successive wide characters
 *    from the object pointed to by src into the object pointed to by dest.t.
 *
 * <INPUT PARAMETERS>
 *    dest                   Destination buffer.
 *    destMax                Size of the destination buffer.
 *    src                     Buffer to copy from.
 *    count                  Number of characters to copy.
 *
 * <OUTPUT PARAMETERS>
 *    dest buffer            is updated.
 *
 * <RETURN VALUE>
 *    EOK                    Success
 *    EINVAL                 dest is  NULL  and destMax != 0 and destMax <= SECUREC_WCHAR_MEM_MAX_LEN
 *                           and count <= destMax
 *    EINVAL_AND_RESET       dest != NULL and src is NULL and destMax != 0
 *                           and destMax <= SECUREC_WCHAR_MEM_MAX_LEN and count <= destMax
 *    ERANGE                 destMax > SECUREC_WCHAR_MEM_MAX_LEN or destMax is 0 or
 *                           (count > destMax and dest is  NULL and destMax != 0
 *                            and destMax <= SECUREC_WCHAR_MEM_MAX_LEN)
 *    ERANGE_AND_RESET       count > destMax and dest  !=  NULL and destMax != 0
 *                           and destMax <= SECUREC_WCHAR_MEM_MAX_LEN
 *    EOVERLAP_AND_RESET     dest buffer and source buffer are overlapped and
 *                           count <= destMax destMax != 0 and destMax <= SECUREC_WCHAR_MEM_MAX_LEN
 *                           and dest  !=  NULL  and src != NULL and dest != src
 *
 *    if an error occurred, dest will be filled with 0 when dest and destMax valid .
 *    If the source and destination overlap, the behavior of wmemcpy_s is undefined.
 *    Use wmemmove_s to handle overlapping regions.
 *******************************************************************************
 */
errno_t wmemcpy_s(wchar_t *dest, size_t destMax, const wchar_t *src, size_t count)
{
    if (destMax == 0 || destMax > SECUREC_WCHAR_MEM_MAX_LEN) {
        SECUREC_ERROR_INVALID_PARAMTER("wmemcpy_s");
        return ERANGE;
    }
    if (count > destMax) {
        SECUREC_ERROR_INVALID_PARAMTER("wmemcpy_s");
        if (dest != NULL) {
            (void)memset(dest, 0, destMax * sizeof(wchar_t));
            return ERANGE_AND_RESET;
        }
        return ERANGE;
    }
    return memcpy_s(dest, destMax * sizeof(wchar_t), src, count * sizeof(wchar_t));
}