// This file is part of the SV-Benchmarks collection of verification tasks:
// https://gitlab.com/sosy-lab/benchmarking/sv-benchmarks
//
// SPDX-FileCopyrightText: 2005-2021 University of Tartu & Technische Universität München
//
// SPDX-License-Identifier: MIT

#include<pthread.h>
#include<stdlib.h>
#define SVCOMP 1

#include <pthread.h>
#include <assert.h>

extern void abort(void);


void reach_error() { assert(0); }
void __VERIFIER_assert(int cond) { if(!(cond)) { ERROR: {reach_error();abort();} } }


extern int __VERIFIER_nondet_int();
void assume_abort_if_not(int cond) {
  if(!cond) {abort();}
}

pthread_mutex_t __global_lock = PTHREAD_MUTEX_INITIALIZER;

#define inc(x) do { pthread_mutex_lock(&__global_lock); (x)++; pthread_mutex_unlock(&__global_lock); } while (0)
#define dec(x) do { pthread_mutex_lock(&__global_lock); (x)--; pthread_mutex_unlock(&__global_lock); } while (0)

#define access(x) do { inc(x); dec(x); } while (0)

#define assert_racefree(x) do { pthread_mutex_lock(&__global_lock); __VERIFIER_assert((x) == 0); pthread_mutex_unlock(&__global_lock); } while (0)

#define access_or_assert_racefree(x) do { if (__VERIFIER_nondet_int()) access(x); else assert_racefree(x); } while (0)

#define N 10000
#define create_threads(t) pthread_t t##_ids[N]; for (int i=0; i<N; i++) pthread_create(&t##_ids[i], NULL, t##_fun, NULL)
#define join_threads(t) for (int i=0; i < N; i++) pthread_join (t##_ids[i], NULL)


struct list_head {
   struct list_head *next ;
   struct list_head *prev ;
};

struct s {
   int datum ;
   struct list_head list ;
};

struct cache {
   struct list_head slot[10] ;
   pthread_mutex_t slots_mutex[10] ;
};

struct cache c  ;

static inline void INIT_LIST_HEAD(struct list_head *list) {
  list->next = list;
  list->prev = list;
}

struct s *new(int x) {
  struct s *p = malloc(sizeof(struct s));
  p->datum = x;
  INIT_LIST_HEAD(&p->list);
  return p;
}

static inline void list_add(struct list_head *new, struct list_head *head) {
  struct list_head *next = head->next;
  next->prev = new;
  new->next = next;
  new->prev = head;
  head->next = new;
}

void *t_fun(void *arg) {
  struct s *pos ;
  int j = __VERIFIER_nondet_int();
  assume_abort_if_not(0 <= j);
  struct list_head  const  *p ;
  struct list_head  const  *q ;

  while (j < 10) {
    pthread_mutex_lock(&c.slots_mutex[j]);
    p = c.slot[j].next;
    pos = (struct s *)((char *)p - (size_t)(& ((struct s *)0)->list));

    while (& pos->list != & c.slot[j]) {
      access_or_assert_racefree(pos->datum); // TODO
      q = pos->list.next;
      pos = (struct s *)((char *)q - (size_t)(& ((struct s *)0)->list));
    }

    pthread_mutex_unlock(&c.slots_mutex[j]);
    j ++;
  }
  return 0;
}

int main() {
  for (int i = 0; i < 10; i++) {
    INIT_LIST_HEAD(&c.slot[i]);
    pthread_mutex_init(&c.slots_mutex[i], NULL);
    for (int j = 0; j < 30; j++) list_add(&new(j*i)->list, &c.slot[i]);
  }

  create_threads(t);
  join_threads(t);
  return 0;
}
