strings.c

#include "sshell.h"
/**
* _strncmp - compares two strings up to n bytes
* @s1: compared to s2
* @s2: compared to s1
* @n: number of bytes
*
* Return: difference between s1 and s2
*/
int _strncmp(char *s1, char *s2, int n)
{
	int i;

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

/**
* _strdup - dupicates string
* @s: to be duplicated
*
* Return: pointer to duplicate string
*/
char *_strdup(char *s)
{
	char *ptr;
	int i, len;

	if (s == NULL)
		return (NULL);

	len = _strlen(s);

	ptr = malloc(sizeof(char) * (len + 1));
	if (!ptr)
		return (NULL);
	for (i = 0; *s != '\0'; s++, i++)
		ptr[i] = s[0];

	ptr[i++] = '\0';
	return (ptr);
}

/**
* _strchr - locates a character in a string
* @s: string to be checked
* @c: character to be located
*
* Return: returns pointer to first occurence of character
* or NULL if character not found
*/
char *_strchr(char *s, char c)
{
	while (*s)
	{
		if (*s == c)
			return (s);
		s++;
	}
	if (!c)
		return (s);
	return (NULL);
}
/**
* test_path - checks whether path is valid
* @path: tokenized path
* @command: user entered command
*
* Return: path appended with command on success
* NULL on failure
*/
char *test_path(char **path, char *command)
{
	int i = 0;
	char *output;

	while (path[i])
	{
		output = append_path(path[i], command);
		if (access(output, F_OK | X_OK) == 0)
			return (output);
		free(output);
		i++;
	}
	return (NULL);
}

/**
* tokenizer - creates tokens from given input
* @line: to be tokenized
*
* Return: array of strings
*/
char **tokenizer(char *line)
{
	char *buf = NULL, *bufp = NULL, *token = NULL, *delim = " :\t\r\n";
	char **tokens = NULL;
	int tokensize = 1;
	size_t index = 0, flag = 0;

	buf = _strdup(line);
	if (!buf)
		return (NULL);
	bufp = buf;

	while (*bufp)
	{
		if (_strchr(delim, *bufp) != NULL && flag == 0)
		{
			tokensize++;
			flag = 1;
		}
		else if (_strchr(delim, *bufp) == NULL && flag == 1)
			flag = 0;
		bufp++;
	}
	tokens = malloc(sizeof(char *) * (tokensize + 1));
	token = strtok(buf, delim);
	while (token)
	{
		tokens[index] = _strdup(token);
		if (tokens[index] == NULL)
		{
			free(tokens);
			return (NULL);
		}
		token = strtok(NULL, delim);
		index++;
	}
	tokens[index] = '\0';
	free(buf);
	return (tokens);
}