PATH

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "fold.h"

#define PATH_SEPARATOR "/"
#define PATH_SEPARATOR_LENGTH (sizeof(PATH_SEPARATOR) - 1)

#define PATH(...) FOLD(path_impl, __VA_ARGS__)
char *path_impl(char *a, char *b) {
    int al = strlen(a);
    int bl = strlen(b);
    
    char *r = malloc(al + PATH_SEPARATOR_LENGTH + bl + 1);
    
    memmove(r, a, al);
    memmove(r + al, PATH_SEPARATOR, PATH_SEPARATOR_LENGTH);
    memmove(r + al + PATH_SEPARATOR_LENGTH, b, bl);
    r[al + PATH_SEPARATOR_LENGTH + bl] = 0;
    
    return r;
}

int main(void) {
    char *t = PATH("eple", "hest", "tiar", "vara");
    printf("%s\n", t);
    
    return 0;
}