quick_sort.c

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 *   Copyright (c) 2025 IMProject Development Team. All rights reserved.
 *   Authors: Juraj Ciberlin <jciberlin1@gmail.com>
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#include "quick_sort.h"

#include "utils.h"

static int32_t
Partition(byte_t* buffer, int32_t start_index, int32_t end_index, int32_t element_size, bool (*compareFun)(void* first,
          void* second)) {
    int32_t pivot_pos = start_index - 1;

    for (int32_t i = start_index; i <= (end_index - 1); ++i) {
        bool compare = compareFun(&buffer[end_index * element_size], &buffer[i * element_size]);
        if (compare) {
            ++pivot_pos;
            Utils_swapElements(&buffer[pivot_pos * element_size], &buffer[i * element_size], (uint32_t)element_size);
        }
    }
    Utils_swapElements(&buffer[(pivot_pos + 1) * element_size], &buffer[end_index * element_size], (uint32_t)element_size);
    ++pivot_pos;
    return pivot_pos;
}

void
QuickSort_sort(byte_t* buffer, int32_t number_of_elements, int32_t element_size,
               bool (*compareFun)(void* first, void* second)) {
    int32_t indexes[MAX_NUM_OF_ELEMENTS] = {0, number_of_elements - 1};

    int32_t top = 1;

    while (top > 0) {
        int32_t end_index = indexes[top];
        --top;
        int32_t start_index = indexes[top];
        --top;

        int32_t pivot_index = Partition(buffer, start_index, end_index, element_size, compareFun);

        if ((pivot_index - 1) > start_index) {
            ++top;
            indexes[top] = start_index;
            ++top;
            indexes[top] = pivot_index - 1;
        }

        if ((pivot_index + 1) < end_index) {
            ++top;
            indexes[top] = pivot_index + 1;
            ++top;
            indexes[top] = end_index;
        }
    }
}