#include <civlc.cvh>
#include <civl-omp.cvh>
#include <stdbool.h>
#include <mem.cvh>
#include <omp.h>

#define OMP_LOCK_UNINITIALIZED -2
#define OMP_LOCK_UNLOCKED -1

// implementations of functions in omp.h go here...

struct omp_lock_t {
  int state; // owner thread id
};

struct omp_nest_lock_t {
  int state; // owner thread id
  int count; // lock counter
};

/************************** OMP LIB Implementations *******************************/

/**** **** **** **** OMP SIMPLE LOCK **** **** **** ****/

/* void omp_init_lock (omp_lock_t *); */
void omp_init_lock(omp_lock_t *lock){  
  lock->state = OMP_LOCK_UNLOCKED;
}

/* void omp_destroy_lock (omp_lock_t *); */
void omp_destroy_lock(omp_lock_t *lock){
  $assert(lock->state == OMP_LOCK_UNLOCKED, 
    "Destroy a simple lock not in 'unlocked' state.");
    
  lock->state = OMP_LOCK_UNINITIALIZED;
}

/* void omp_set_lock (omp_lock_t *); */
void $omp_set_lock(omp_lock_t *lock, int tid) {
  $atomic {
    $assert(lock->state != OMP_LOCK_UNINITIALIZED, 
      "Set a simple lock in 'uninitialized' state.");
    $when(lock->state == OMP_LOCK_UNLOCKED) {
      $read_set_push();
      $write_set_push();
      lock->state = tid;
      $read_set_pop();
      $write_set_pop();
    }
  }
}

/* void omp_unset_lock (omp_lock_t *); */
void $omp_unset_lock(omp_lock_t *lock, int tid) {
  $atomic {
    $assert(lock->state == tid, 
      "Unset a simple lock not owned: caller_tid: %d, owner_tid: %d.", 
      tid, lock->state);
    $assert(lock->state > OMP_LOCK_UNLOCKED, 
      "Unset a simple lock not in 'locked' state.");
    $read_set_push();
    $write_set_push();
    lock->state = OMP_LOCK_UNLOCKED;
    $read_set_pop();
    $write_set_pop();
  }
}

/* int omp_test_lock (omp_lock_t *); */
int $omp_test_lock(omp_lock_t *lock, int tid) {
  int rtn = 0;
  $atomic {
    $assert(lock->state != OMP_LOCK_UNINITIALIZED, 
      "Set a simple lock in 'uninitialized' state.");
    $assert(lock->state != tid, 
      "Test a simple lock owned by the caller: tid: %d.", tid);
    if (lock->state == OMP_LOCK_UNLOCKED) {
      $read_set_push();
      $write_set_push();
      lock->state = tid;
      $read_set_pop();
      $write_set_pop();
      rtn = 1;
    }
  }
  return rtn;
}

/**** **** **** **** OMP NESTED LOCK **** **** **** ****/


/* void omp_init_nest_lock (omp_nest_lock_t *); */
void omp_init_nest_lock(omp_nest_lock_t *lock){
  $assert(lock->state == OMP_LOCK_UNINITIALIZED, 
    "Init a simple lock not in 'uninitialized' state.");
  
  lock->state = OMP_LOCK_UNLOCKED;
  lock->count = 0;
}

/* void omp_destroy_nest_lock (omp_nest_lock_t *); */
void omp_destroy_nest_lock(omp_nest_lock_t *lock){
  $assert(lock->state == OMP_LOCK_UNLOCKED, 
    "Destroy a simple lock not in 'unlocked' state.");
    
  lock->state = OMP_LOCK_UNINITIALIZED;
  lock->count = 0;
}

/* void omp_set_nest_lock (omp_nest_lock_t *); */
void $omp_set_nest_lock(omp_nest_lock_t *lock, int tid) {
  $atomic {
    $assert(lock->state != OMP_LOCK_UNINITIALIZED, 
      "Set a simple lock in 'uninitialized' state.");
    $when( lock->state == OMP_LOCK_UNLOCKED 
        || lock->state == tid) {
      $read_set_push();
      $write_set_push();
      lock->state = tid;
      lock->count = lock->count + 1;
      $read_set_pop();
      $write_set_pop();
    }
  }
}

/* void omp_unset_nest_lock (omp_nest_lock_t *); */
void $omp_unset_nest_lock(omp_nest_lock_t *lock, int tid) {
  $atomic {
    $assert(lock->state == tid, 
      "Unset a simple lock not owned: caller_tid: %d, owner_tid: %d.", 
      tid, lock->state);
    $assert(lock->state > OMP_LOCK_UNLOCKED, 
      "Unset a simple lock not in 'locked' state.");
    $read_set_push();
    $write_set_push();
    lock->count = lock->count - 1;
    if (lock->count == 0)
      lock->state = OMP_LOCK_UNLOCKED;
    $read_set_pop();
    $write_set_pop();
  }
}

/* int omp_test_nest_lock (omp_nest_lock_t *); */
int $omp_test_nest_lock(omp_nest_lock_t *lock, int tid) {
  $atomic {
    $assert(lock->state != OMP_LOCK_UNINITIALIZED, 
      "Set a simple lock in 'uninitialized' state.");
    $assert(lock->state != tid, 
      "Test a simple lock owned by the caller: tid: %d.", tid);
    if ( lock->state == OMP_LOCK_UNLOCKED
      || lock->state == tid) {
      $read_set_push();
      $write_set_push();
      lock->state = tid;
      lock->count = lock->count + 1;
      $read_set_pop();
      $write_set_pop();
    }
  }
  return lock->count;
}

$abstract double OMP_time(int time_count);

/* double omp_get_wtime (void); */
double omp_get_wtime() {
  int OMP_time_count = $next_time_count();
  double result = OMP_time(OMP_time_count);
  
  if (OMP_time_count > 0) {
    $assume(result > OMP_time(OMP_time_count-1));
  } else {
    $assume(result > 0);
  }
  return result;
}

/* OpenMP Library Routines that transformed by CIVL:
 *   void omp_set_num_threads (int);
 *   int  omp_get_num_threads (void);
 *   int  omp_get_max_threads (void);
 *   int  omp_get_thread_num (void);
 *   int  omp_get_num_procs (void);
 */


/* Unsupported Functions: 
 *   int    omp_in_parallel (void);
 *   void   omp_set_dynamic (int);
 *   int    omp_get_dynamic (void);
 *   void   omp_set_nested  (int);
 *   int    omp_get_nested  (void);
 *   double omp_get_wtick   (void);
*/