simple_shell/str_func.c at master · yungryce/simple_shell · GitHub

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#include "main.h"

/**
 * _strcmp - Compares two strings.
 * @s1: The first string to be compared.
 * @s2: The second string to be compared.
 *
 * Return: Positive byte difference if s1 > s2
 *         0 if s1 = s2
 *         Negative byte difference if s1 < s2
 */
int _strcmp(char *s1, char *s2)
{
	while (*s1 && *s1 == *s2)
	{
		s1++;
		s2++;
	}

	if (*s1 != *s2)
		return (*s1 - *s2);

	return (0);
}

/**
 * _strncmp - Compare two strings.
 * @s1: Pointer to a string.
 * @s2: Pointer to a string.
 * @n: The first n bytes of the strings to compare.
 *
 * Return: Less than 0 if s1 is shorter than s2.
 *         0 if s1 and s2 match.
 *         Greater than 0 if s1 is longer than s2.
 */
int _strncmp(const char *s1, const char *s2, size_t n)
{
	size_t i;
	int diff;

	for (i = 0; s1[i] && s2[i] && i < n; i++)
	{
		diff = (unsigned char)s1[i] - (unsigned char)s2[i];
		if (diff != 0)
			return (diff);
	}
	if (i == n)
		return (0);

	return ((unsigned char)s1[i] - (unsigned char)s2[i]);
}


/**
 * _strchr - locates a character in a string,
 * @s: string.
 * @c: character.
 * Return: the pointer to the first occurrence of the character c.
 */
char *_strchr(char *s, char c)
{
	while (*s)
	{
		if (*s == c)
			return (s);
		s++;
	}

	return (*s == c ? s : NULL);
}


/**
 * _strrchr - locates the last character in a string,
 * @s: string.
 * @c: character.
 * Return: the pointer to the first occurrence of the character c.
 */
char *_strrchr(char *s, int c)
{
	char *last_char = NULL;

	while (*s)
	{
		if (*s == c)
			last_char = s;
		s++;
	}

	return (last_char);
}