/* Libc stubs for pthread functions.  Hurd pthread version.

   Copyright (C) 2002-2018 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/>.  */

#include <errno.h>

#include <dlfcn.h>

#include <stdlib.h>

#include <shlib-compat.h>

#include <pthread-functions.h>

#include <libc-lock.h>

#include <fork.h>

/* Pointers to the libc functions.  */

struct pthread_functions __libc_pthread_functions attribute_hidden;

int __libc_pthread_functions_init attribute_hidden;

#define FORWARD2(name, rettype, decl, params, defaction) \

rettype									      \

name decl								      \

{									      \

  if (!__libc_pthread_functions_init)					      \

    defaction;								      \

									      \

  return PTHFCT_CALL (ptr_##name, params);				      \

}

/* Same as FORWARD2, only without return.  */

#define FORWARD_NORETURN(name, rettype, decl, params, defaction) \

rettype									      \

name decl								      \

{									      \

  if (!__libc_pthread_functions_init)					      \

    defaction;								      \

									      \

  PTHFCT_CALL (ptr_##name, params);					      \

}

#define FORWARD(name, decl, params, defretval) \

  FORWARD2 (name, int, decl, params, return defretval)

FORWARD (pthread_attr_destroy, (pthread_attr_t *attr), (attr), 0)

FORWARD (pthread_attr_init, (pthread_attr_t *attr), (attr), 0)

FORWARD (pthread_attr_getdetachstate,

	 (const pthread_attr_t *attr, int *detachstate), (attr, detachstate),

	 0)

FORWARD (pthread_attr_setdetachstate, (pthread_attr_t *attr, int detachstate),

	 (attr, detachstate), 0)

FORWARD (pthread_attr_getinheritsched,

	 (const pthread_attr_t *attr, int *inherit), (attr, inherit), 0)

FORWARD (pthread_attr_setinheritsched, (pthread_attr_t *attr, int inherit),

	 (attr, inherit), 0)

FORWARD (pthread_attr_getschedparam,

	 (const pthread_attr_t *attr, struct sched_param *param),

	 (attr, param), 0)

FORWARD (pthread_attr_setschedparam,

	 (pthread_attr_t *attr, const struct sched_param *param),

	 (attr, param), 0)

FORWARD (pthread_attr_getschedpolicy,

	 (const pthread_attr_t *attr, int *policy), (attr, policy), 0)

FORWARD (pthread_attr_setschedpolicy, (pthread_attr_t *attr, int policy),

	 (attr, policy), 0)

FORWARD (pthread_attr_getscope,

	 (const pthread_attr_t *attr, int *scope), (attr, scope), 0)

FORWARD (pthread_attr_setscope, (pthread_attr_t *attr, int scope),

	 (attr, scope), 0)

FORWARD (pthread_condattr_destroy, (pthread_condattr_t *attr), (attr), 0)

FORWARD (pthread_condattr_init, (pthread_condattr_t *attr), (attr), 0)

FORWARD (pthread_cond_broadcast, (pthread_cond_t *cond), (cond), 0)

FORWARD (pthread_cond_destroy, (pthread_cond_t *cond), (cond), 0)

FORWARD (pthread_cond_init,

	 (pthread_cond_t *cond, const pthread_condattr_t *cond_attr),

	 (cond, cond_attr), 0)

FORWARD (pthread_cond_signal, (pthread_cond_t *cond), (cond), 0)

FORWARD (pthread_cond_wait, (pthread_cond_t *cond, pthread_mutex_t *mutex),

	 (cond, mutex), 0)

FORWARD (pthread_cond_timedwait,

	 (pthread_cond_t *cond, pthread_mutex_t *mutex,

	  const struct timespec *abstime), (cond, mutex, abstime), 0)

FORWARD (pthread_equal, (pthread_t thread1, pthread_t thread2),

	 (thread1, thread2), 1)

/* Use an alias to avoid warning, as pthread_exit is declared noreturn.  */

FORWARD_NORETURN (__pthread_exit, void, (void *retval), (retval),

		  exit (EXIT_SUCCESS))

strong_alias (__pthread_exit, pthread_exit);

FORWARD (pthread_getschedparam,

	 (pthread_t target_thread, int *policy, struct sched_param *param),

	 (target_thread, policy, param), 0)

FORWARD (pthread_setschedparam,

	 (pthread_t target_thread, int policy,

	  const struct sched_param *param), (target_thread, policy, param), 0)

FORWARD (pthread_mutex_destroy, (pthread_mutex_t *mutex), (mutex), 0)

FORWARD (pthread_mutex_init,

	 (pthread_mutex_t *mutex, const pthread_mutexattr_t *mutexattr),

	 (mutex, mutexattr), 0)

FORWARD (pthread_mutex_lock, (pthread_mutex_t *mutex), (mutex), 0)

FORWARD (pthread_mutex_unlock, (pthread_mutex_t *mutex), (mutex), 0)

FORWARD2 (pthread_self, pthread_t, (void), (), return 0)

FORWARD (__pthread_setcancelstate, (int state, int *oldstate),

	 (state, oldstate), 0)

strong_alias (__pthread_setcancelstate, pthread_setcancelstate);

FORWARD (pthread_setcanceltype, (int type, int *oldtype), (type, oldtype), 0)

struct __pthread_cancelation_handler *dummy_list;

FORWARD2 (__pthread_get_cleanup_stack, struct __pthread_cancelation_handler **,

	  (void), (), return &dummy_list);

/* Fork interaction */

struct atfork

{

  void (*prepare) (void);

  void (*parent) (void);

  void (*child) (void);

  void *dso_handle;

  struct atfork *prev;

  struct atfork *next;

};

/* TODO: better locking */

__libc_lock_define_initialized (static, atfork_lock);

static struct atfork *fork_handlers, *fork_last_handler;

static void

atfork_pthread_prepare (void)

{

  struct atfork *handlers, *last_handler;

  __libc_lock_lock (atfork_lock);

  handlers = fork_handlers;

  last_handler = fork_last_handler;

  __libc_lock_unlock (atfork_lock);

  if (last_handler == NULL)

    return;

  while (1)

    {

      if (last_handler->prepare != NULL)

	last_handler->prepare ();

      if (last_handler == handlers)

	break;

      last_handler = last_handler->prev;

    }

}

text_set_element (_hurd_atfork_prepare_hook, atfork_pthread_prepare);

static void

atfork_pthread_parent (void)

{

  struct atfork *handlers;

  __libc_lock_lock (atfork_lock);

  handlers = fork_handlers;

  __libc_lock_unlock (atfork_lock);

  while (handlers != NULL)

    {

      if (handlers->parent != NULL)

	handlers->parent ();

      handlers = handlers->next;

    }

}

text_set_element (_hurd_atfork_parent_hook, atfork_pthread_parent);

static void

atfork_pthread_child (void)

{

  struct atfork *handlers;

  __libc_lock_lock (atfork_lock);

  handlers = fork_handlers;

  __libc_lock_unlock (atfork_lock);

  while (handlers != NULL)

    {

      if (handlers->child != NULL)

	handlers->child ();

      handlers = handlers->next;

    }

}

text_set_element (_hurd_atfork_child_hook, atfork_pthread_child);

int

__register_atfork (void (*prepare) (void),

		   void (*parent) (void),

		   void (*child) (void),

		   void *dso_handle)

{

  struct atfork *new = malloc (sizeof (*new));

  if (new == NULL)

    return errno;

  new->prepare = prepare;

  new->parent = parent;

  new->child = child;

  new->dso_handle = dso_handle;

  new->prev = NULL;

  __libc_lock_lock (atfork_lock);

  new->next = fork_handlers;

  if (fork_handlers != NULL)

    fork_handlers->prev = new;

  fork_handlers = new;

  if (fork_last_handler == NULL)

    fork_last_handler = new;

  __libc_lock_unlock (atfork_lock);

  return 0;

}

libc_hidden_def (__register_atfork)

void

__unregister_atfork (void *dso_handle)

{

  struct atfork **handlers, *prev = NULL, *next;

  __libc_lock_lock (atfork_lock);

  handlers = &fork_handlers;

  while (*handlers != NULL)

    {

      if ((*handlers)->dso_handle == dso_handle)

	{

	  /* Drop this handler from the list.  */

	  if (*handlers == fork_last_handler)

	    {

	      /* Was last, new last is prev, if any.  */

	      fork_last_handler = prev;

	    }

	  next = (*handlers)->next;

	  if (next != NULL)

	    next->prev = prev;

	  *handlers = next;

	}

      else

	{

	  /* Just proceed to next handler.  */

	  prev = *handlers;

	  handlers = &prev->next;

	}

    }

  __libc_lock_unlock (atfork_lock);

}