simple_shell/SS_realloc.c at master · Stephen842/simple_shell · GitHub

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#include "shell.h"
/**
 * _memset - this function fills a block of memory with a constant byte
 * @s: parameter showing the pointer to the memory area
 * @b: parameter showing the byte to fill *s with
 * @n: parameter of the amount of bytes to be filled
 * Return: s as a pointer
 */

char *_memset(char *s, char b, unsigned int n)
{
	unsigned int a;

	for (a = 0; a < n; a++)
		s[a] = b;
	return (s);
}

/**
 * ffree -this function frees dynamically allocated array of strings
 * @pp: function parameter indicating string of strings
 * Return: void
 */

void ffree(char **pp)
{
	char **tmp = pp;

	if (!pp)
		return;
	while (*pp)
	{
		free(*pp);
		pp++;
	}
	free(tmp);
}

/**
 * _realloc - this function reallocates a block of memory to a new size
 * @ptr: function parameter indicating a pointer
 * @old_size: function parameter indicating the byte size of previous block
 * @new_size: function parameter indicating the byte size of new block
 * Return: void
 */

void *_realloc(void *ptr, unsigned int old_size, unsigned int new_size)
{
	char *new_ptr = NULL;
	char *destination;
	unsigned int i;

	if (!ptr)
		return (malloc(new_size));

	if (!new_size)
	{
		free(ptr);
		return (NULL);
	}

	if (new_size == old_size)
		return (ptr);

	new_ptr = malloc(new_size);
	if (!new_ptr)
		return (NULL);

	destination = new_ptr;

	for (i = 0; i < old_size && i < new_size; i++)
	destination[i] = ((char *)ptr)[i];

	free(ptr);
	return (new_ptr);
}