#include <stdio.h>
#include <stdlib.h>

// return the length of string to the null terminator
int x_strlen(char* str){
	char* ptr = str;
	while(*ptr != '\0'){
		ptr++;
	}
	return ptr - str;
}

// copy one string to another destination
// must include the size of the destination
void x_strcpy(char* dest, char* src, const int size_dest){
	char* dest_ptr = dest;
	char* src_ptr = src;
	int i = 0;

	while(*src_ptr != '\0'){
		if (i >= size_dest){
			fprintf(stderr, "Error: x_strcpy\nSource string exeeds destination memory\n");
			exit(1);
		}
		*dest_ptr = *src_ptr;
		dest_ptr++;
		src_ptr++;
		i++;
	}

}
// compare two strings
// return 0 if equal to eachother
// return -1 if not
int x_strcmp (char* str1, char* str2){
	char* ptr1 = str1;
	char* ptr2 = str2;

	while(*ptr1 != '\0' && *ptr2 != '\0'){
		if(*ptr1 != *ptr2){
			return -1;
		}

		ptr1++;
		ptr2++;
	}

	// if havent reached the end of one of the strings
	if (*ptr1 != '\0' || *ptr2 != '\0'){
		return -1;
	}

	return 0;
}


// concatinate two strings
char* x_strconcat(char* str1, char* str2){

	char* new_string;

	int len1 = x_strlen(str1);
	int len2 = x_strlen(str2);
	int new_length = len1 + len2;

	new_string = malloc( sizeof(*new_string) * new_length );
	x_strcpy(new_string, str1, new_length);
	x_strcpy(&new_string[len1], str2, new_length - len1);

	return new_string;
}