timebase.h

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/* timebase.h -- management of calls, time bases and heaps for moxc */

#define STOPRATE 0xFFFFL

/***************************************************************************
* call structure
****************************************************************************/

/* ---NOTE!!! if you change MAX_CALL_ARGS, change CALLARGS macro below--- */
#define MAX_CALL_ARGS 8
typedef struct call_args_struct {
  long arg[MAX_CALL_ARGS];
} call_args_node;

typedef struct call {
    union {
        struct {
            time_type time;     /* virtual time of this call */
            int priority;       /* an 8-bit the priority, low priority first */
            int (*routine)();   /* who to call */
            call_args_node p; /* what to pass */
        } e;
        struct call *p; /* used to link free calls */
    } u;
} *call_type, call_node;

/* CALLARGS - given a call_type, this macro generates an argument list */
/*
 * NOTE: originally, I thought call->u.e.p (a structure), would do it, but
 * Lattice C for the Amiga has a compiler bug, and even in places where the
 * bug doesn't show up, the code generated for the structure passing is 
 * a sequence of two loops: one to copy data to a local area on the stack,
 * and one to push this data (a byte at a time!) to the top of the stack.
 * With Lattice (and perhaps others, I haven't checked), it's better to 
 * push the data in-line.
 */
#ifdef LATTICE
#define CARG(n) call->u.e.p.arg[n]
#define CALLARGS(call) CARG(0), CARG(1), CARG(2), CARG(3), \
                CARG(4), CARG(5), CARG(6), CARG(7)
#else
#define CALLARGS(call) call->u.e.p
#endif

/***************************************************************************
* timebase structure
****************************************************************************/

typedef struct timebase_struct {
    struct timebase_struct *next;       /* used for list */
    time_type next_time;
    time_type virt_base;
    time_type real_base;
    time_type rate; /* ratio of real/virt time, STOPRATE or more is infinity */
    short heap_size;
    short heap_max;
    call_type *heap;
} timebase_node, *timebase_type;

extern timebase_type timebase_queue;

#define call_alloc() ((call_type) memget(sizeof(call_node)))
#define call_free(c) memfree((char *) (c), sizeof(call_node))

timebase_type   timebase_create(int maxsize);
void            callinsert(timebase_type base, call_type call);
void            callshow(call_type call);
void            timebase_free(timebase_type timebase);
void            insert_base(timebase_type timebase);
void            remove_base(timebase_type timebase);
call_type       remove_call(timebase_type a_timebase);
void            set_rate(timebase_type base, time_type rate);
void            set_virttime(timebase_type base, time_type vtime);
void            timebase_use(timebase_type base);

#define real_to_virt(base, rtime) ((base)->rate == 0 ? MAXTIME : \
 ((base)->virt_base + (((rtime) - (base)->real_base) << 8) / (base)->rate))

#define virt_to_real(base, vtime) ((base)->rate >= STOPRATE ? \
 ((base)->virt_base > vtime ? (base)->real_base : MAXTIME) : \
 (base)->real_base + ((((vtime) - (base)->virt_base) * (base)->rate) >> 8))

#define virt_to_real_256(base, vtime) ((base)->rate >= STOPRATE ? \
 ((base)->virt_base > vtime ? (base)->real_base << 8 : MAXTIME) : \
 ((base)->real_base << 8) + ((((vtime) - (base)->virt_base) * (base)->rate)))