string_compare_guy.c

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

// string_compare_guy compares the contents of the left hand side, length with the contents of the
// right hand side, length and returns 1 if the right hand side (needle) is inside the left hand
// side (haystack).
static int string_compare_guy(char* lhs, int llength, char* rhs, int rlength) {
    char lnz[llength + 1];
    memcpy(lnz, lhs, llength);
    lnz[llength] = 0;

    char rnz[rlength + 1];
    memcpy(rnz, rhs, rlength);
    rnz[rlength] = 0;

    char *result = strstr(lnz, rhs);

    return result == NULL ? 0 : 1;
}

int main() {
    int retcode = 0;

    printf("Comparing foo and bar\n");
    if(string_compare_guy("foo", 3, "bar", 3)) {
        retcode++;
        printf("failure\n");
    } else {
        printf("passed\n");
    }

    printf("trying to find foobar in foo\n");
    if(string_compare_guy("foo", 3, "foobar", 6)) {
        retcode++;
        printf("failure\n");
    } else {
        printf("passed\n");
    }

    printf("trying to find foo in foobar\n");
    if(string_compare_guy("foobar", 3, "foo", 6)) {
        printf("passed\n");
    } else {
        retcode++;
        printf("failure\n");
    }

    return retcode;
}