/*
 * Copyright (c) 2011 Luka Marčetić<paxcoder@gmail.com>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted.
 *
 * There's ABSOLUTELY NO WARRANTY, express or implied.
 */

//A union for return values of functions
union ret {
    char  c;
    char* s;
    int   i;
    void* vp;
};

///Atrucutre designed to hold test data
struct test
{
    char         *fn_name; //function name for the output
    unsigned int narg;     //number of arguments that the function takes
    unsigned int ndata;    //number of test datasets
    struct data {
        struct arguments {unsigned int nr; void *vp;} *arg;
        void   *ret;
        int    err;
    } *data;
};

///Handy macro to get a certain value from an element via the arg void pointer
///Note: it requires arg and i to be a pointer to struct arguments & an iterator
//       hint: see iter and arg arguments for index()
#define ARGV(TYPE, INDEX) ((TYPE *) arg[INDEX].vp)[index(i, arg, INDEX)]

/**
 ** \returns the cardinality of a cartesian product of sets of arguments
 **  ie the number of iterations required to cover all argument values
 ** \param t a test to which the arguments belong
 ** \param d an index of the dataset from t to be taken into consideration
 **/
size_t iters(struct test t, unsigned int d)
{
    size_t i, product=1;
    for (i=0; i<t.narg; ++i)
        product *= t.data[d].arg[i].nr;
    return product;
}

/**
 ** Given an iteration, returns the index of an argument value. That is,
 ** if iter is the number of a certain tuple from the cartesian product, and
 ** i the nr of an element from the tuple, the function returns its index in
 ** the original set - ie the (i-th) factor set to the cartesian product)
 ** \param iter current iteration
 ** \param arg a struct arguments pointer from struct test
 ** \param i index of the arguments for which the element index is requried
 **/
size_t index(size_t iter, struct arguments *arg, int i)
{
    size_t x = iter;
    for(int j=0; j<i; ++j)
        x /= arg[j].nr; //an integer value
    x %= arg[i].nr;
    return x;
}