#ifndef SNC_H
#define SNC_H

/* ========================== *
 * Mutex
 * ========================== */

struct snc_lock {
    struct snc_mutex *mutex;
    b32 exclusive;
};

struct alignas(64) snc_mutex {
    /* Bit 31   = Exclusive lock is held
     * Bit 30   = Exclusive lock is pending
     * Bit 0-30 = Shared locks count
     */
    struct atomic32 v;

#if RTC
    struct atomic32 exclusive_fiber_id;
    u8 _pad[56];
#else
    u8 _pad[60];
#endif
};
STATIC_ASSERT(sizeof(struct snc_mutex) == 64);  /* Padding validation */
STATIC_ASSERT(alignof(struct snc_mutex) == 64);  /* Prevent false sharing */

struct snc_lock snc_lock_spin_e(struct snc_mutex *m, i32 spin);
struct snc_lock snc_lock_spin_s(struct snc_mutex *m, i32 spin);
struct snc_lock snc_lock_e(struct snc_mutex *m);
struct snc_lock snc_lock_s(struct snc_mutex *m);
void snc_unlock(struct snc_lock *lock);

#if RTC
# define snc_assert_locked_e(l, m) ASSERT((l)->mutex == (m) && (l)->exclusive == 1)
# define snc_assert_locked_e_or_s(l, m) ASSERT((l)->mutex == (m))
#else
# define snc_assert_locked_e(l, m) (UNUSED)l
# define snc_assert_locked_e_or_s(l, m) (UNUSED)l
#endif

/* ========================== *
 * Condition variable
 * ========================== */

struct alignas(64) snc_cv {
    struct atomic64 wake_gen;
    u8 _pad[56];
};
STATIC_ASSERT(sizeof(struct snc_cv) == 64);  /* Padding validation */
STATIC_ASSERT(alignof(struct snc_cv) == 64);  /* Prevent false sharing */

void snc_cv_wait(struct snc_cv *cv, struct snc_lock *lock);
void snc_cv_wait_time(struct snc_cv *cv, struct snc_lock *l, i64 timeout_ns);
void snc_cv_signal(struct snc_cv *cv, i32 count);

/* ========================== *
 * Counter
 * ========================== */

struct alignas(64) snc_counter {
    struct atomic64 v;
    u8 _pad[56];
};
STATIC_ASSERT(sizeof(struct snc_counter) == 64);  /* Padding validation */
STATIC_ASSERT(alignof(struct snc_counter) == 64);  /* Prevent false sharing */

void snc_counter_add(struct snc_counter *counter, i64 x);
void snc_counter_wait(struct snc_counter *counter);

#endif