array.c

// Copyright 2018,2023 Jeisson Hidalgo <jeisson.hidalgo@ucr.ac.cr> CC-BY 4.0
#include "array.h"

#include <assert.h>
#include <stdlib.h>

static array_t array_elements = NULL;
static size_t array_capacity = 0;
static size_t array_count = 0;

array_t array_create(size_t capacity) {
  assert(capacity);
  array_capacity = capacity;
  array_count = 0;
  return array_elements = (void**)malloc(capacity * sizeof(void*));
}

void array_destroy(array_t array) { free(array); }

int array_increase_capacity(array_t array) {
  size_t new_capacity = 10 * array_capacity;
  array_t new_elements = (void**)realloc(array, new_capacity * sizeof(void*));
  if (new_elements == NULL) return -1;

  array_capacity = new_capacity;
  array_elements = new_elements;

  return 0;  // Success
}

int array_decrease_capacity(array_t array) {
  size_t new_capacity = array_capacity / 10;
  if (new_capacity < 10) return 0;

  array_t new_elements = (void**)realloc(array, new_capacity * sizeof(void*));
  if (new_elements == NULL) return -1;

  array_capacity = new_capacity;
  array_elements = new_elements;

  return 0;  // Success
}

size_t array_get_count(const array_t array) {
  (void)array;
  return array_count;
}

void* array_get_element(array_t array, size_t index) {
  assert(index < array_get_count(array));
  return array[index];
}

int array_append(array_t array, void* element) {
  if (array_count == array_capacity) {
    if (!array_increase_capacity(array)) {
      return -1;
    }
  }

  array[array_count++] = element;
  return 0;  // Success
}

size_t array_find_first(const array_t array, const void* element,
                        size_t start_pos) {
  for (size_t index = start_pos; index < array_count; ++index) {
    if (array[index] == element) {
      return index;
    }
  }

  return array_not_found;
}

int array_remove_first(array_t array, const void* element, size_t start_pos) {
  size_t index = array_find_first(array, element, start_pos);
  if (index == array_not_found) return -1;

  for (--array_count; index < array_count; ++index) {
    array_elements[index] = array_elements[index + 1];
  }
  if (array_count == array_capacity / 10) {
    array_decrease_capacity(array);
  }

  return 0;  // Removed
}