_realloc.c

#include "shell.h"
/**
* *_memset - function that fills memory with a constant byte
* @n: bytes of memory area pointed to by s
* @s: with the constant byte
* @b: memory area
* Return: A pointer to the memory area at s
*/
char *_memset(char *s, char b, unsigned int n)
{
	unsigned int i = 0;

	while (i < n)
	{
		s[i] = b;
		i++;
	}
	return (s);
}

/**
 * _bfree - Function frees a pointer
 * @ptr: address of the pointer to free
 * Return: Return 1 if freed,else 0 if otherwise
 */
int _bfree(void **ptr)
{
	if (ptr && *ptr)
	{
		free(*ptr);
		*ptr = NULL;
		return (1);
	}
	return (0);
}

/**
 * _ffree - frees a string of strings
 * @pp: string of strings
 */
void _ffree(char **pp)
{
	char **a = pp;

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

/**
 * _realloc - reallocates a block of memory
 * @ptr: pointer to previous malloc'ated block
 * @old_size: byte size of previous block
 * @new_size: byte size of new block
 * Return: pointer to da ol'block nameen.
 */
void *_realloc(void *ptr, unsigned int old_size, unsigned int new_size)
{
	char *p;

	if (!ptr)
		return (malloc(new_size));
	if (!new_size)
		return (free(ptr), NULL);
	if (new_size == old_size)
		return (ptr);

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

	old_size = old_size < new_size ? old_size : new_size;
	while (old_size--)
		p[old_size] = ((char *)ptr)[old_size];
	free(ptr);
	return (p);
}