/*
 * str_ops.c
 *
 *  Created on: Aug 27, 2011
 *      Author: Tiberiu
 */
#include <types.h>
#include <ctype.h>

uint32 strlen (string s)
{
	string end = s;
	while (*end != '\0')
		end++;

	return (uint32)(end - s);
}

int32 strcmp (string a, string b)
{
	unsigned char c1, c2;

	while (*a != '\0' && *b != '\0' && *a == *b) {
		a++; b++;
	}

	c1 = (*(unsigned char*) a);
	c2 = (*(unsigned char*) b);
	return ((c1 < c2) ? -1 : (c1 > c2));
}

int32 strncmp (string a, string b, uint32 n)
{
	unsigned char uc1, uc2;
	if (!n) return 0;

	while (n-- > 0 && *a == *b) {
		if (n == 0 || (*a == *b  && *a == '\0')) return 0;
		a++; b++;
	}

	uc1 = (* (unsigned char*)a);
	uc2 = (* (unsigned char*)b);
	return ((uc1 < uc2) ? -1 : (uc1 > uc2));
}

int32 strcasecmp (string a, string b)
{
	unsigned char c1, c2;

	while (*a != '\0' && *b != '\0' && tolower(*a) == tolower(*b)) {
		a++; b++;
	}

	c1 = tolower(*(unsigned char*) a);
	c2 = tolower(*(unsigned char*) b);
	return ((c1 < c2) ? -1 : (c1 > c2));
}

string strcpy (string s1, const string s2)
{
	char *dst = s1;
	const char *src = s2;

	while ((*dst++ = *src++) != '\0') ;

	return s1;
}

char* strchr (string s, int c)
{
	while (*s != '\0' && *s != (char)c) s++;
	return ((*s == (char)c) ? (char*)s : NULL);
}

char* strrchr (string s, int c)
{
	string last = NULL;

	if (c == '\0') return strchr(s, c);
	while ((s = strchr(s, c)) != NULL)
		last = s; s++;

	return (char*)last;
}