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

int x_strlen(char* str){
	char* ptr = str;
	while(*ptr != '\0'){
		ptr++;
	}
	return ptr - str;
}

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++;
	}

}

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;
}

int main(){

	char x[] = "hlo";
	char y[] = "world";

	//printf("%d\n", x_strlen(x));
	//printf("%d\n", x_strlen(x));

	char* z = x_strconcat(x,y);

	puts(z);

	//free(z);

	return 0;
}