/* big number functions needed by taipan.c.

	The implementation will actually use the Atari ROM floating point
	routines. To port Taipan to a new cc65 platform, the functions listed
	here will have to be rewritten, but taipan.c itself shouldn't need
	changing (at least, not in relation to bignums!) */

#define bignum(x) char x[6]
#define bignump char *


/* zero */
#define BIG_0 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }

/* constant initializer for 1.05 goes here */
#define BIG_1_05 { 0x40, 0x01, 0x05, 0x00, 0x00, 0x00 }

/* bignum 100, used for score calculations in final_stats() */
#define BIG_10 { 0x41, 0x01, 0x00, 0x00, 0x00, 0x00 }

// void int_to_big(int i, bignum *b);
// void uint_to_big(unsigned int i, bignum *b);

extern void __fastcall__ ulong_to_big(const unsigned long l, bignump b);

/* returns 0 for success, nonzero for fail (overflow or negative) */
extern char __fastcall__ big_to_ulong(bignump b, unsigned long *l);

/* this should work like cprintfancy(), but doesn't need centering. */
// void cprint_big(const bignum *b);

/* basic math functions. conceptually they return a boolean for
	success, but only division has error checking.
	all can be read as: dest = arg2 OP arg3;
	modulus isn't implemented as taipan doesn't use it for the bank.
 */
// char big_add(bignum *dest, bignum *addend1, bignum *addend2);
// char big_sub(bignum *dest, bignum *minuend, bignum *subtrahend);
// char big_mul(bignum *dest, bignum *multiplicand, bignum *multiplier);
// char big_div(bignum *dest, bignum *dividend, bignum *divisor);

/* comparison. Perl spaceship operator, <=>
	returns  | if
	---------+----------------
	    0    | a == b
	    1    | a > b
	   -1    | a < b
 */
// signed char big_cmp(const bignum *a, const bignum *b)