/* Internal defenitions for pthreads library.

   Copyright (C) 2000-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library;  if not, see

   <http://www.gnu.org/licenses/>.  */

#ifndef _PT_INTERNAL_H

#define _PT_INTERNAL_H	1

#include <pthread.h>

#include <stddef.h>

#include <sched.h>

#include <signal.h>

#include <assert.h>

#include <bits/types/res_state.h>

#include <atomic.h>

#include <pt-key.h>

#include <pt-sysdep.h>

#include <pt-machdep.h>

#if IS_IN (libpthread)

# include <ldsodefs.h>

#endif

/* Thread state.  */

enum pthread_state

{

  /* The thread is running and joinable.  */

  PTHREAD_JOINABLE = 0,

  /* The thread is running and detached.  */

  PTHREAD_DETACHED,

  /* A joinable thread exited and its return code is available.  */

  PTHREAD_EXITED,

  /* The thread structure is unallocated and available for reuse.  */

  PTHREAD_TERMINATED

};

#ifndef PTHREAD_KEY_MEMBERS

# define PTHREAD_KEY_MEMBERS

#endif

#ifndef PTHREAD_SYSDEP_MEMBERS

# define PTHREAD_SYSDEP_MEMBERS

#endif

#if !(IS_IN (libpthread))

/* Type of the TCB.  */

typedef struct

{

  void *tcb;			/* Points to this structure.  */

  void *dtv;			/* Vector of pointers to TLS data.  */

  thread_t self;		/* This thread's control port.  */

} tcbhead_t;

#endif /* ! IS_IN (libpthread) */

/* This structure describes a POSIX thread.  */

struct __pthread

{

  /* Thread ID.  */

  pthread_t thread;

  unsigned int nr_refs;		/* Detached threads have a self reference only,

				   while joinable threads have two references.

				   These are used to keep the structure valid at

				   thread destruction.  Detaching/joining a thread

				   drops a reference.  */

  /* Cancellation.  */

  pthread_mutex_t cancel_lock;	/* Protect cancel_xxx members.  */

  void (*cancel_hook) (void *);	/* Called to unblock a thread blocking

				   in a cancellation point (namely,

				   __pthread_cond_timedwait_internal).  */

  void *cancel_hook_arg;

  int cancel_state;

  int cancel_type;

  int cancel_pending;

  struct __pthread_cancelation_handler *cancelation_handlers;

  /* Thread stack.  */

  void *stackaddr;

  size_t stacksize;

  size_t guardsize;

  int stack;			/* Nonzero if the stack was allocated.  */

  /* Exit status.  */

  void *status;

  /* Thread state.  */

  enum pthread_state state;

  pthread_mutex_t state_lock;	/* Locks the state.  */

  pthread_cond_t state_cond;	/* Signalled when the state changes.  */

  /* Resolver state.  */

  struct __res_state res_state;

  /* Thread context.  */

  struct pthread_mcontext mcontext;

  PTHREAD_KEY_MEMBERS

  PTHREAD_SYSDEP_MEMBERS

  tcbhead_t *tcb;

  /* Queue links.  Since PREVP is used to determine if a thread has been

     awaken, it must be protected by the queue lock.  */

  struct __pthread *next, **prevp;

};

/* Enqueue an element THREAD on the queue *HEAD.  */

static inline void

__pthread_enqueue (struct __pthread **head, struct __pthread *thread)

{

  assert (thread->prevp == 0);

  thread->next = *head;

  thread->prevp = head;

  if (*head)

    (*head)->prevp = &thread->next;

  *head = thread;

}

/* Dequeue the element THREAD from the queue it is connected to.  */

static inline void

__pthread_dequeue (struct __pthread *thread)

{

  assert (thread);

  assert (thread->prevp);

  if (thread->next)

    thread->next->prevp = thread->prevp;

  *thread->prevp = thread->next;

  thread->prevp = 0;

}

/* Iterate over QUEUE storing each element in ELEMENT.  */

#define __pthread_queue_iterate(queue, element)				\

  for (struct __pthread *__pdi_next = (queue);				\

       ((element) = __pdi_next)						\

	 && ((__pdi_next = __pdi_next->next),				\

	     1);							\

       )

/* Iterate over QUEUE dequeuing each element, storing it in

   ELEMENT.  */

#define __pthread_dequeuing_iterate(queue, element)			\

  for (struct __pthread *__pdi_next = (queue);				\

       ((element) = __pdi_next)						\

	 && ((__pdi_next = __pdi_next->next),				\

	     ((element)->prevp = 0),					\

	     1);							\

       )

/* The total number of threads currently active.  */

extern unsigned int __pthread_total;

/* The total number of thread IDs currently in use, or on the list of

   available thread IDs.  */

extern int __pthread_num_threads;

/* Concurrency hint.  */

extern int __pthread_concurrency;

/* Array of __pthread structures and its lock.  Indexed by the pthread

   id minus one.  (Why not just use the pthread id?  Because some

   brain-dead users of the pthread interface incorrectly assume that 0

   is an invalid pthread id.)  */

extern struct __pthread **__pthread_threads;

extern pthread_rwlock_t __pthread_threads_lock;

#define __pthread_getid(thread) \

  ({ struct __pthread *__t;                                                  \

     __pthread_rwlock_rdlock (&__pthread_threads_lock);                      \

     __t = __pthread_threads[thread - 1];                                    \

     __pthread_rwlock_unlock (&__pthread_threads_lock);                      \

     __t; })

#define __pthread_setid(thread, pthread) \

  __pthread_rwlock_wrlock (&__pthread_threads_lock);                         \

  __pthread_threads[thread - 1] = pthread;                                   \

  __pthread_rwlock_unlock (&__pthread_threads_lock);

/* Similar to pthread_self, but returns the thread descriptor instead

   of the thread ID.  */

#ifndef _pthread_self

extern struct __pthread *_pthread_self (void);

#endif

/* Initialize the pthreads library.  */

extern void ___pthread_init (void);

/* Internal version of pthread_create.  Rather than return the new

   tid, we return the whole __pthread structure in *PTHREAD.  */

extern int __pthread_create_internal (struct __pthread **__restrict pthread,

				      const pthread_attr_t *__restrict attr,

				      void *(*start_routine) (void *),

				      void *__restrict arg);

/* Allocate a new thread structure and a pthread thread ID (but not a

   kernel thread or a stack).  THREAD has one reference.  */

extern int __pthread_alloc (struct __pthread **thread);

/* Deallocate the thread structure.  This is the dual of

   __pthread_alloc (N.B. it does not call __pthread_stack_dealloc nor

   __pthread_thread_terminate).  THREAD loses one reference and is

   released if the reference counter drops to 0.  */

extern void __pthread_dealloc (struct __pthread *thread);

/* Allocate a stack of size STACKSIZE.  The stack base shall be

   returned in *STACKADDR.  */

extern int __pthread_stack_alloc (void **stackaddr, size_t stacksize);

/* Deallocate the stack STACKADDR of size STACKSIZE.  */

extern void __pthread_stack_dealloc (void *stackaddr, size_t stacksize);

/* Setup thread THREAD's context.  */

extern int __pthread_setup (struct __pthread *__restrict thread,

			    void (*entry_point) (struct __pthread *,

						 void *(*)(void *),

						 void *),

			    void *(*start_routine) (void *),

			    void *__restrict arg);

/* Allocate a kernel thread (and any miscellaneous system dependent

   resources) for THREAD; it must not be placed on the run queue.  */

extern int __pthread_thread_alloc (struct __pthread *thread);

/* Start THREAD making it eligible to run.  */

extern int __pthread_thread_start (struct __pthread *thread);

/* Terminate the kernel thread associated with THREAD, and deallocate its

   stack as well as any other kernel resource associated with it.

   In addition, THREAD looses one reference.

   This function can be called by any thread, including the target thread.

   Since some resources that are destroyed along the kernel thread are

   stored in thread-local variables, the conditions required for this

   function to behave correctly are a bit unusual : as long as the target

   thread hasn't been started, any thread can terminate it, but once it

   has started, no other thread can terminate it, so that thread-local

   variables created by that thread are correctly released.  */

extern void __pthread_thread_terminate (struct __pthread *thread);

/* Called by a thread just before it calls the provided start

   routine.  */

extern void __pthread_startup (void);

/* Block THREAD.  */

extern void __pthread_block (struct __pthread *thread);

/* Block THREAD until *ABSTIME is reached.  */

extern error_t __pthread_timedblock (struct __pthread *__restrict thread,

				     const struct timespec *__restrict abstime,

				     clockid_t clock_id);

/* Wakeup THREAD.  */

extern void __pthread_wakeup (struct __pthread *thread);

/* Perform a cancelation.  The CANCEL_LOCK member of the given thread must

   be locked before calling this function, which must unlock it.  */

extern int __pthread_do_cancel (struct __pthread *thread);

/* Initialize the thread specific data structures.  THREAD must be the

   calling thread.  */

extern error_t __pthread_init_specific (struct __pthread *thread);

/* Call the destructors on all of the thread specific data in THREAD.

   THREAD must be the calling thread.  */

extern void __pthread_destroy_specific (struct __pthread *thread);

/* Initialize newly create thread *THREAD's signal state data

   structures.  */

extern error_t __pthread_sigstate_init (struct __pthread *thread);

/* Destroy the signal state data structures associcated with thread

   *THREAD.  */

extern void __pthread_sigstate_destroy (struct __pthread *thread);

/* Modify thread *THREAD's signal state.  */

extern error_t __pthread_sigstate (struct __pthread *__restrict thread, int how,

				   const sigset_t *__restrict set,

				   sigset_t *__restrict oset,

				   int clear_pending);

/* Default thread attributes.  */

extern const struct __pthread_attr __pthread_default_attr;

/* Default barrier attributes.  */

extern const struct __pthread_barrierattr __pthread_default_barrierattr;

/* Default mutex attributes.  */

extern const struct __pthread_mutexattr __pthread_default_mutexattr;

/* Default rdlock attributes.  */

extern const struct __pthread_rwlockattr __pthread_default_rwlockattr;

/* Default condition attributes.  */

extern const struct __pthread_condattr __pthread_default_condattr;

#endif /* pt-internal.h */