nuttx/sched/pthread_internal.h
patacongo f29250c671 Correct a race condition in the pthread join logic. Sometimes the join structure was being deallocated while it was still needed.
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@180 42af7a65-404d-4744-a932-0658087f49c3
2007-03-30 00:49:11 +00:00

132 lines
4.6 KiB
C

/************************************************************
* pthread_internal.h
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name Gregory Nutt nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
************************************************************/
#ifndef __PTHREAD_INTERNAL_H
#define __PTHREAD_INTERNAL_H
/************************************************************
* Included Files
************************************************************/
#include <sys/types.h>
#include <pthread.h>
#include <nuttx/compiler.h>
/************************************************************
* Definitions
************************************************************/
/************************************************************
* Public Type Declarations
************************************************************/
/* The following defines an entry in the pthread logic's
* local data set. Note that this structure is used to
* implemented a singly linked list. This structure
* is used (instead of, say, a binary search tree) because
* the data set will be searched using the pid as
* a key -- a process IDs will always be created in a
* montonically increasing fashion.
*/
struct join_s
{
FAR struct join_s *next; /* Implements link list */
ubyte crefs; /* Reference count */
boolean started; /* TRUE: pthread started. */
boolean detached; /* TRUE: pthread_detached'ed */
boolean terminated; /* TRUE: detach'ed+exit'ed */
pthread_t thread; /* Includes pid */
sem_t exit_sem; /* Implements join */
sem_t data_sem; /* Implements join */
pthread_addr_t exit_value; /* Returned data */
};
typedef struct join_s join_t;
/************************************************************
* Public Variables
************************************************************/
/* This is the head of a private singly linked list. It
* is used to retain information about the spawned threads.
*/
extern FAR join_t *g_pthread_head;
extern FAR join_t *g_pthread_tail;
/* Mutually exclusive access to this data set is enforced with
* the following (un-named) semaphore.
*/
extern sem_t g_join_semaphore;
/* This keys track of the number of global keys that have been
* allocated.
*/
extern ubyte g_pthread_num_keys;
/* Default pthread attributes */
extern FAR pthread_attr_t g_default_pthread_attr;
/************************************************************
* Public Function Prototypes
************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C" {
#else
#define EXTERN extern
#endif
EXTERN void weak_function pthread_initialize(void);
EXTERN int pthread_completejoin(pid_t pid, FAR void *exit_value);
EXTERN void pthread_destroyjoin(FAR join_t *pjoin);
EXTERN FAR join_t *pthread_findjoininfo(pid_t pid);
EXTERN int pthread_givesemaphore(sem_t *sem);
EXTERN FAR join_t *pthread_removejoininfo(pid_t pid);
EXTERN int pthread_takesemaphore(sem_t *sem);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __PTHREAD_INTERNAL_H */