#ifdef INTELLISENSE_DIRECTIVES
#pragma once
#include "base/macros.h"
#include "base/base_types.h"
#endif

// Copyright (c) 2024 Epic Games Tools
// Licensed under the MIT license (https://opensource.org/license/mit/)

////////////////////////////////
//~ rjf: Includes

#define _GNU_SOURCE
#include <features.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <linux/limits.h>
#include <time.h>
#include <dirent.h>
#include <pthread.h>
#include <sys/syscall.h>
#include <signal.h>
#include <errno.h>
#include <dlfcn.h>
#include <sys/sysinfo.h>
#include <sys/random.h>

int pthread_setname_np(pthread_t thread, const char *name);
int pthread_getname_np(pthread_t thread, char *name, size_t size);

typedef struct tm       tm;
typedef struct timespec timespec;

////////////////////////////////
//~ rjf: File Iterator

typedef struct OS_LNX_FileIter OS_LNX_FileIter;
struct OS_LNX_FileIter
{
  DIR*           dir;
  struct dirent* dp;
  String8        path;
};
StaticAssert(sizeof(Member(OS_FileIter, memory)) >= sizeof(OS_LNX_FileIter), os_lnx_file_iter_size_check);

////////////////////////////////
//~ rjf: Safe Call Handler Chain

typedef struct OS_LNX_SafeCallChain OS_LNX_SafeCallChain;
struct OS_LNX_SafeCallChain
{
  OS_LNX_SafeCallChain*  next;
  OS_ThreadFunctionType* fail_handler;
  void *ptr;
};

////////////////////////////////
//~ rjf: Entities

typedef enum OS_LNX_EntityKind
{
  OS_LNX_EntityKind_Thread,
  OS_LNX_EntityKind_Mutex,
  OS_LNX_EntityKind_RWMutex,
  OS_LNX_EntityKind_ConditionVariable,
}
OS_LNX_EntityKind;

typedef struct OS_LNX_Entity OS_LNX_Entity;
struct OS_LNX_Entity
{
  OS_LNX_Entity*    next;
  OS_LNX_EntityKind kind;
  union
  {
    struct
    {
      pthread_t              handle;
      OS_ThreadFunctionType* func;
      void*                  ptr;
    } thread;

    pthread_mutex_t  mutex_handle;
    pthread_rwlock_t rwmutex_handle;

    struct
    {
      pthread_cond_t  cond_handle;
      pthread_mutex_t rwlock_mutex_handle;
    } cv;
  };
};

////////////////////////////////
//~ rjf: State

typedef struct OS_LNX_State OS_LNX_State;
struct OS_LNX_State
{
  Arena*          arena;
  OS_SystemInfo   system_info;
  OS_ProcessInfo  process_info;
  pthread_mutex_t entity_mutex;
  Arena*          entity_arena;
  OS_LNX_Entity*  entity_free;
};
k
////////////////////////////////
//~ rjf: Globals

global OS_LNX_State os_lnx_state = {0};
thread_static OS_LNX_SafeCallChain *os_lnx_safe_call_chain = 0;

////////////////////////////////
//~ rjf: Helpers

internal DateTime       os_lnx_date_time_from_tm(tm in, U32 msec);
internal tm             os_lnx_tm_from_date_time(DateTime dt);
internal timespec       os_lnx_timespec_from_date_time( DateTime dt);
internal DenseTime      os_lnx_dense_time_from_timespec(timespec in);
internal FileProperties os_lnx_file_properties_from_stat(struct stat *s);
internal void           os_lnx_safe_call_sig_handler    (int x);
k
////////////////////////////////
//~ rjf: Entities

internal OS_LNX_Entity* os_lnx_entity_alloc(OS_LNX_EntityKind kind);
internal void           os_lnx_entity_release(OS_LNX_Entity *entity);

////////////////////////////////
//~ rjf: Thread Entry Point

internal void *os_lnx_thread_entry_point(void *ptr);