|  | @@ -1,241 +0,0 @@
 | 
	
		
			
				|  |  | -/*
 | 
	
		
			
				|  |  | - * This file contains the old semaphore code that we need to
 | 
	
		
			
				|  |  | - * preserve for glibc-2.0 backwards compatibility. Port to glibc 2.1
 | 
	
		
			
				|  |  | - * done by Cristian Gafton.
 | 
	
		
			
				|  |  | - */
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -/* Linuxthreads - a simple clone()-based implementation of Posix        */
 | 
	
		
			
				|  |  | -/* threads for Linux.                                                   */
 | 
	
		
			
				|  |  | -/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr)              */
 | 
	
		
			
				|  |  | -/*                                                                      */
 | 
	
		
			
				|  |  | -/* This program is free software; you can redistribute it and/or        */
 | 
	
		
			
				|  |  | -/* modify it under the terms of the GNU Library General Public License  */
 | 
	
		
			
				|  |  | -/* as published by the Free Software Foundation; either version 2       */
 | 
	
		
			
				|  |  | -/* of the License, or (at your option) any later version.               */
 | 
	
		
			
				|  |  | -/*                                                                      */
 | 
	
		
			
				|  |  | -/* This program 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 Library General Public License for more details.                 */
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -/* Semaphores a la POSIX 1003.1b */
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -#include <errno.h>
 | 
	
		
			
				|  |  | -#include "pthread.h"
 | 
	
		
			
				|  |  | -#include "internals.h"
 | 
	
		
			
				|  |  | -#include "spinlock.h"
 | 
	
		
			
				|  |  | -#include "restart.h"
 | 
	
		
			
				|  |  | -#include "queue.h"
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -typedef struct {
 | 
	
		
			
				|  |  | -    long int sem_status;
 | 
	
		
			
				|  |  | -    int sem_spinlock;
 | 
	
		
			
				|  |  | -} old_sem_t;
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -/* Maximum value the semaphore can have.  */
 | 
	
		
			
				|  |  | -#define SEM_VALUE_MAX   ((int) ((~0u) >> 1))
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -static __inline__ int sem_compare_and_swap(old_sem_t *sem, long oldval, long newval)
 | 
	
		
			
				|  |  | -{
 | 
	
		
			
				|  |  | -    return compare_and_swap(&sem->sem_status, oldval, newval, &sem->sem_spinlock);
 | 
	
		
			
				|  |  | -}
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -/* The state of a semaphore is represented by a long int encoding
 | 
	
		
			
				|  |  | -   either the semaphore count if >= 0 and no thread is waiting on it,
 | 
	
		
			
				|  |  | -   or the head of the list of threads waiting for the semaphore.
 | 
	
		
			
				|  |  | -   To distinguish the two cases, we encode the semaphore count N
 | 
	
		
			
				|  |  | -   as 2N+1, so that it has the lowest bit set.
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -   A sequence of sem_wait operations on a semaphore initialized to N
 | 
	
		
			
				|  |  | -   result in the following successive states:
 | 
	
		
			
				|  |  | -     2N+1, 2N-1, ..., 3, 1, &first_waiting_thread, &second_waiting_thread, ...
 | 
	
		
			
				|  |  | -*/
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -static void sem_restart_list(pthread_descr waiting);
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -int __old_sem_init(old_sem_t *sem, int pshared, unsigned int value);
 | 
	
		
			
				|  |  | -int __old_sem_init(old_sem_t *sem, int pshared, unsigned int value)
 | 
	
		
			
				|  |  | -{
 | 
	
		
			
				|  |  | -    if (value > SEM_VALUE_MAX) {
 | 
	
		
			
				|  |  | -	errno = EINVAL;
 | 
	
		
			
				|  |  | -	return -1;
 | 
	
		
			
				|  |  | -    }
 | 
	
		
			
				|  |  | -    if (pshared) {
 | 
	
		
			
				|  |  | -	errno = ENOSYS;
 | 
	
		
			
				|  |  | -	return -1;
 | 
	
		
			
				|  |  | -    }
 | 
	
		
			
				|  |  | -  sem->sem_spinlock = 0;
 | 
	
		
			
				|  |  | -  sem->sem_status = ((long)value << 1) + 1;
 | 
	
		
			
				|  |  | -  return 0;
 | 
	
		
			
				|  |  | -}
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -/* Function called by pthread_cancel to remove the thread from
 | 
	
		
			
				|  |  | -   waiting inside __old_sem_wait. Here we simply unconditionally
 | 
	
		
			
				|  |  | -   indicate that the thread is to be woken, by returning 1. */
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -static int old_sem_extricate_func(void *obj attribute_unused, pthread_descr th attribute_unused)
 | 
	
		
			
				|  |  | -{
 | 
	
		
			
				|  |  | -    return 1;
 | 
	
		
			
				|  |  | -}
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -int __old_sem_wait(old_sem_t * sem);
 | 
	
		
			
				|  |  | -int __old_sem_wait(old_sem_t * sem)
 | 
	
		
			
				|  |  | -{
 | 
	
		
			
				|  |  | -    long oldstatus, newstatus;
 | 
	
		
			
				|  |  | -    volatile pthread_descr self = thread_self();
 | 
	
		
			
				|  |  | -    pthread_descr * th;
 | 
	
		
			
				|  |  | -    pthread_extricate_if extr;
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -    /* Set up extrication interface */
 | 
	
		
			
				|  |  | -    extr.pu_object = 0;
 | 
	
		
			
				|  |  | -    extr.pu_extricate_func = old_sem_extricate_func;
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -    while (1) {
 | 
	
		
			
				|  |  | -	/* Register extrication interface */
 | 
	
		
			
				|  |  | -	__pthread_set_own_extricate_if(self, &extr);
 | 
	
		
			
				|  |  | -	do {
 | 
	
		
			
				|  |  | -            oldstatus = sem->sem_status;
 | 
	
		
			
				|  |  | -            if ((oldstatus & 1) && (oldstatus != 1))
 | 
	
		
			
				|  |  | -		newstatus = oldstatus - 2;
 | 
	
		
			
				|  |  | -            else {
 | 
	
		
			
				|  |  | -		newstatus = (long) self;
 | 
	
		
			
				|  |  | -		self->p_nextwaiting = (pthread_descr) oldstatus;
 | 
	
		
			
				|  |  | -	    }
 | 
	
		
			
				|  |  | -	}
 | 
	
		
			
				|  |  | -	while (! sem_compare_and_swap(sem, oldstatus, newstatus));
 | 
	
		
			
				|  |  | -	if (newstatus & 1) {
 | 
	
		
			
				|  |  | -	    /* We got the semaphore. */
 | 
	
		
			
				|  |  | -	  __pthread_set_own_extricate_if(self, 0);
 | 
	
		
			
				|  |  | -	    return 0;
 | 
	
		
			
				|  |  | -	}
 | 
	
		
			
				|  |  | -	/* Wait for sem_post or cancellation */
 | 
	
		
			
				|  |  | -	suspend(self);
 | 
	
		
			
				|  |  | -	__pthread_set_own_extricate_if(self, 0);
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -	/* This is a cancellation point */
 | 
	
		
			
				|  |  | -	if (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE) {
 | 
	
		
			
				|  |  | -	    /* Remove ourselves from the waiting list if we're still on it */
 | 
	
		
			
				|  |  | -	    /* First check if we're at the head of the list. */
 | 
	
		
			
				|  |  | -            do {
 | 
	
		
			
				|  |  | -		oldstatus = sem->sem_status;
 | 
	
		
			
				|  |  | -		if (oldstatus != (long) self) break;
 | 
	
		
			
				|  |  | -		newstatus = (long) self->p_nextwaiting;
 | 
	
		
			
				|  |  | -	    }
 | 
	
		
			
				|  |  | -            while (! sem_compare_and_swap(sem, oldstatus, newstatus));
 | 
	
		
			
				|  |  | -            /* Now, check if we're somewhere in the list.
 | 
	
		
			
				|  |  | -	       There's a race condition with sem_post here, but it does not matter:
 | 
	
		
			
				|  |  | -	       the net result is that at the time pthread_exit is called,
 | 
	
		
			
				|  |  | -	       self is no longer reachable from sem->sem_status. */
 | 
	
		
			
				|  |  | -            if (oldstatus != (long) self && (oldstatus & 1) == 0) {
 | 
	
		
			
				|  |  | -		for (th = &(((pthread_descr) oldstatus)->p_nextwaiting);
 | 
	
		
			
				|  |  | -		     *th != NULL && *th != (pthread_descr) 1;
 | 
	
		
			
				|  |  | -		     th = &((*th)->p_nextwaiting)) {
 | 
	
		
			
				|  |  | -		    if (*th == self) {
 | 
	
		
			
				|  |  | -			*th = self->p_nextwaiting;
 | 
	
		
			
				|  |  | -			break;
 | 
	
		
			
				|  |  | -		    }
 | 
	
		
			
				|  |  | -		}
 | 
	
		
			
				|  |  | -	    }
 | 
	
		
			
				|  |  | -            __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME);
 | 
	
		
			
				|  |  | -	}
 | 
	
		
			
				|  |  | -    }
 | 
	
		
			
				|  |  | -}
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -int __old_sem_trywait(old_sem_t * sem);
 | 
	
		
			
				|  |  | -int __old_sem_trywait(old_sem_t * sem)
 | 
	
		
			
				|  |  | -{
 | 
	
		
			
				|  |  | -  long oldstatus, newstatus;
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -  do {
 | 
	
		
			
				|  |  | -    oldstatus = sem->sem_status;
 | 
	
		
			
				|  |  | -    if ((oldstatus & 1) == 0 || (oldstatus == 1)) {
 | 
	
		
			
				|  |  | -      errno = EAGAIN;
 | 
	
		
			
				|  |  | -      return -1;
 | 
	
		
			
				|  |  | -    }
 | 
	
		
			
				|  |  | -    newstatus = oldstatus - 2;
 | 
	
		
			
				|  |  | -  }
 | 
	
		
			
				|  |  | -  while (! sem_compare_and_swap(sem, oldstatus, newstatus));
 | 
	
		
			
				|  |  | -  return 0;
 | 
	
		
			
				|  |  | -}
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -int __old_sem_post(old_sem_t * sem);
 | 
	
		
			
				|  |  | -int __old_sem_post(old_sem_t * sem)
 | 
	
		
			
				|  |  | -{
 | 
	
		
			
				|  |  | -  long oldstatus, newstatus;
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -  do {
 | 
	
		
			
				|  |  | -    oldstatus = sem->sem_status;
 | 
	
		
			
				|  |  | -    if ((oldstatus & 1) == 0)
 | 
	
		
			
				|  |  | -      newstatus = 3;
 | 
	
		
			
				|  |  | -    else {
 | 
	
		
			
				|  |  | -      if (oldstatus >= SEM_VALUE_MAX) {
 | 
	
		
			
				|  |  | -        /* Overflow */
 | 
	
		
			
				|  |  | -        errno = ERANGE;
 | 
	
		
			
				|  |  | -        return -1;
 | 
	
		
			
				|  |  | -      }
 | 
	
		
			
				|  |  | -      newstatus = oldstatus + 2;
 | 
	
		
			
				|  |  | -    }
 | 
	
		
			
				|  |  | -  }
 | 
	
		
			
				|  |  | -  while (! sem_compare_and_swap(sem, oldstatus, newstatus));
 | 
	
		
			
				|  |  | -  if ((oldstatus & 1) == 0)
 | 
	
		
			
				|  |  | -    sem_restart_list((pthread_descr) oldstatus);
 | 
	
		
			
				|  |  | -  return 0;
 | 
	
		
			
				|  |  | -}
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -int __old_sem_getvalue(old_sem_t * sem, int * sval);
 | 
	
		
			
				|  |  | -int __old_sem_getvalue(old_sem_t * sem, int * sval)
 | 
	
		
			
				|  |  | -{
 | 
	
		
			
				|  |  | -  long status = sem->sem_status;
 | 
	
		
			
				|  |  | -  if (status & 1)
 | 
	
		
			
				|  |  | -    *sval = (int)((unsigned long) status >> 1);
 | 
	
		
			
				|  |  | -  else
 | 
	
		
			
				|  |  | -    *sval = 0;
 | 
	
		
			
				|  |  | -  return 0;
 | 
	
		
			
				|  |  | -}
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -int __old_sem_destroy(old_sem_t * sem);
 | 
	
		
			
				|  |  | -int __old_sem_destroy(old_sem_t * sem)
 | 
	
		
			
				|  |  | -{
 | 
	
		
			
				|  |  | -  if ((sem->sem_status & 1) == 0) {
 | 
	
		
			
				|  |  | -    errno = EBUSY;
 | 
	
		
			
				|  |  | -    return -1;
 | 
	
		
			
				|  |  | -  }
 | 
	
		
			
				|  |  | -  return 0;
 | 
	
		
			
				|  |  | -}
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -/* Auxiliary function for restarting all threads on a waiting list,
 | 
	
		
			
				|  |  | -   in priority order. */
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -static void sem_restart_list(pthread_descr waiting)
 | 
	
		
			
				|  |  | -{
 | 
	
		
			
				|  |  | -  pthread_descr th, towake, *p;
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -  /* Sort list of waiting threads by decreasing priority (insertion sort) */
 | 
	
		
			
				|  |  | -  towake = NULL;
 | 
	
		
			
				|  |  | -  while (waiting != (pthread_descr) 1) {
 | 
	
		
			
				|  |  | -    th = waiting;
 | 
	
		
			
				|  |  | -    waiting = waiting->p_nextwaiting;
 | 
	
		
			
				|  |  | -    p = &towake;
 | 
	
		
			
				|  |  | -    while (*p != NULL && th->p_priority < (*p)->p_priority)
 | 
	
		
			
				|  |  | -      p = &((*p)->p_nextwaiting);
 | 
	
		
			
				|  |  | -    th->p_nextwaiting = *p;
 | 
	
		
			
				|  |  | -    *p = th;
 | 
	
		
			
				|  |  | -  }
 | 
	
		
			
				|  |  | -  /* Wake up threads in priority order */
 | 
	
		
			
				|  |  | -  while (towake != NULL) {
 | 
	
		
			
				|  |  | -    th = towake;
 | 
	
		
			
				|  |  | -    towake = towake->p_nextwaiting;
 | 
	
		
			
				|  |  | -    th->p_nextwaiting = NULL;
 | 
	
		
			
				|  |  | -    restart(th);
 | 
	
		
			
				|  |  | -  }
 | 
	
		
			
				|  |  | -}
 | 
	
		
			
				|  |  | -
 | 
	
		
			
				|  |  | -#if defined __PIC__ && defined DO_VERSIONING
 | 
	
		
			
				|  |  | -symbol_version (__old_sem_init, sem_init, GLIBC_2.0);
 | 
	
		
			
				|  |  | -symbol_version (__old_sem_wait, sem_wait, GLIBC_2.0);
 | 
	
		
			
				|  |  | -symbol_version (__old_sem_trywait, sem_trywait, GLIBC_2.0);
 | 
	
		
			
				|  |  | -symbol_version (__old_sem_post, sem_post, GLIBC_2.0);
 | 
	
		
			
				|  |  | -symbol_version (__old_sem_getvalue, sem_getvalue, GLIBC_2.0);
 | 
	
		
			
				|  |  | -symbol_version (__old_sem_destroy, sem_destroy, GLIBC_2.0);
 | 
	
		
			
				|  |  | -#endif
 | 
	
		
			
				|  |  | -
 |