array.h

/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * 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.
 */

#pragma once

#include <stdlib.h>

#define array_copy(dest, src, count)                          \
    do {                                                      \
        STATIC_ASSERT(sizeof((dest)[0]) == sizeof((src)[0])); \
        memcpy((dest), (src), sizeof((dest)[0]) * (count));   \
    } while (false)

#define array_shift(array, dest, src)                                          \
    do {                                                                       \
        assert(src <= countof((array)));                                       \
        assert(dest <= countof((array)));                                      \
        memmove((array) + (dest), (array) + (src),                             \
                sizeof((array)[0]) * (countof((array)) - MAX((src), (dest)))); \
    } while (false)

#define array_insert(array, index, value)           \
    do {                                            \
        array_shift((array), (index) + 1, (index)); \
        (array)[(index)] = (value);                 \
    } while (false)

#define array_insert_overflow(array, index, value, overflow_value) \
    do {                                                           \
        if (index == countof((array))) {                           \
            *overflow_value = value;                               \
        } else {                                                   \
            *overflow_value = (array)[countof((array)) - 1];       \
            array_insert((array), (index), (value));               \
        }                                                          \
    } while (false)

#define array_clear_end(array, start)                              \
    do {                                                           \
        memset((array) + (start), 0,                               \
               sizeof((array)[0]) * (countof((array)) - (start))); \
    } while (false)

#define array_shift_down(array, dest, src)                             \
    do {                                                               \
        assert(src > dest);                                            \
        assert(src <= countof((array)));                               \
        array_shift((array), (dest), (src));                           \
        array_clear_end((array), countof((array)) - ((src) - (dest))); \
    } while (false)