+
−/* Thread-local storage in multithreaded situations.
+
−   Copyright (C) 2005, 2007-2012 Free Software Foundation, Inc.
+
−
+
−   This program is free software: you can redistribute it and/or modify
+
−   it under the terms of the GNU General Public License as published by
+
−   the Free Software Foundation; either version 3 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 General Public License for more details.
+
−
+
−   You should have received a copy of the GNU General Public License
+
−   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
−
+
−/* Written by Bruno Haible <bruno@clisp.org>, 2005.  */
+
−
+
−/* This file contains thread-local storage primitives for use with a given
+
−   thread library.  It does not contain primitives for creating threads or
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−   for other multithreading primitives.
+
−
+
−     Type:                      gl_tls_key_t
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−     Initialization:            gl_tls_key_init (name, destructor);
+
−     Getting per-thread value:  gl_tls_get (name)
+
−     Setting per-thread value:  gl_tls_set (name, pointer);
+
−     De-initialization:         gl_tls_key_destroy (name);
+
−   Equivalent functions with control of error handling:
+
−     Initialization:            err = glthread_tls_key_init (&name, destructor);
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−     Setting per-thread value:  err = glthread_tls_set (&name, pointer);
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−     De-initialization:         err = glthread_tls_key_destroy (&name);
+
−
+
−   A per-thread value is of type 'void *'.
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−
+
−   A destructor is a function pointer of type 'void (*) (void *)', called
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−   when a thread exits, and taking the last per-thread value as argument.  It
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−   is unspecified whether the destructor function is called when the last
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−   per-thread value is NULL.  On some platforms, the destructor function is
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−   not called at all.
+
−*/
+
−
+
−
+
−#ifndef _TLS_H
+
−#define _TLS_H
+
−
+
−#include <errno.h>
+
−#include <stdlib.h>
+
−
+
−/* ========================================================================= */
+
−
+
−#if USE_POSIX_THREADS
+
−
+
−/* Use the POSIX threads library.  */
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−
+
−# include <pthread.h>
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−
+
−# if PTHREAD_IN_USE_DETECTION_HARD
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−
+
−/* The pthread_in_use() detection needs to be done at runtime.  */
+
−#  define pthread_in_use() \
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−     glthread_in_use ()
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−extern int glthread_in_use (void);
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−
+
−# endif
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−
+
−# if USE_POSIX_THREADS_WEAK
+
−
+
−/* Use weak references to the POSIX threads library.  */
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−
+
−#  pragma weak pthread_key_create
+
−#  pragma weak pthread_getspecific
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−#  pragma weak pthread_setspecific
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−#  pragma weak pthread_key_delete
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−#  ifndef pthread_self
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−#   pragma weak pthread_self
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−#  endif
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−
+
−#  if !PTHREAD_IN_USE_DETECTION_HARD
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−#   pragma weak pthread_cancel
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−#   define pthread_in_use() (pthread_cancel != NULL)
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−#  endif
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−
+
−# else
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−
+
−#  if !PTHREAD_IN_USE_DETECTION_HARD
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−#   define pthread_in_use() 1
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−#  endif
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−
+
−# endif
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−
+
−/* ------------------------- gl_tls_key_t datatype ------------------------- */
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−
+
−typedef union
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−        {
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−          void *singlethread_value;
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−          pthread_key_t key;
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−        }
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−        gl_tls_key_t;
+
−# define glthread_tls_key_init(KEY, DESTRUCTOR) \
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−    (pthread_in_use ()                              \
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−     ? pthread_key_create (&(KEY)->key, DESTRUCTOR) \
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−     : ((KEY)->singlethread_value = NULL, 0))
+
−# define gl_tls_get(NAME) \
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−    (pthread_in_use ()                  \
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−     ? pthread_getspecific ((NAME).key) \
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−     : (NAME).singlethread_value)
+
−# define glthread_tls_set(KEY, POINTER) \
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−    (pthread_in_use ()                             \
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−     ? pthread_setspecific ((KEY)->key, (POINTER)) \
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−     : ((KEY)->singlethread_value = (POINTER), 0))
+
−# define glthread_tls_key_destroy(KEY) \
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−    (pthread_in_use () ? pthread_key_delete ((KEY)->key) : 0)
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−
+
−#endif
+
−
+
−/* ========================================================================= */
+
−
+
−#if USE_PTH_THREADS
+
−
+
−/* Use the GNU Pth threads library.  */
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−
+
−# include <pth.h>
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−
+
−# if USE_PTH_THREADS_WEAK
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−
+
−/* Use weak references to the GNU Pth threads library.  */
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−
+
−#  pragma weak pth_key_create
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−#  pragma weak pth_key_getdata
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−#  pragma weak pth_key_setdata
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−#  pragma weak pth_key_delete
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−
+
−#  pragma weak pth_cancel
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−#  define pth_in_use() (pth_cancel != NULL)
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−
+
−# else
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−
+
−#  define pth_in_use() 1
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−
+
−# endif
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−
+
−/* ------------------------- gl_tls_key_t datatype ------------------------- */
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−
+
−typedef union
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−        {
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−          void *singlethread_value;
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−          pth_key_t key;
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−        }
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−        gl_tls_key_t;
+
−# define glthread_tls_key_init(KEY, DESTRUCTOR) \
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−    (pth_in_use ()                                             \
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−     ? (!pth_key_create (&(KEY)->key, DESTRUCTOR) ? errno : 0) \
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−     : ((KEY)->singlethread_value = NULL, 0))
+
−# define gl_tls_get(NAME) \
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−    (pth_in_use ()                  \
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−     ? pth_key_getdata ((NAME).key) \
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−     : (NAME).singlethread_value)
+
−# define glthread_tls_set(KEY, POINTER) \
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−    (pth_in_use ()                                            \
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−     ? (!pth_key_setdata ((KEY)->key, (POINTER)) ? errno : 0) \
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−     : ((KEY)->singlethread_value = (POINTER), 0))
+
−# define glthread_tls_key_destroy(KEY) \
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−    (pth_in_use ()                                \
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−     ? (!pth_key_delete ((KEY)->key) ? errno : 0) \
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−     : 0)
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−
+
−#endif
+
−
+
−/* ========================================================================= */
+
−
+
−#if USE_SOLARIS_THREADS
+
−
+
−/* Use the old Solaris threads library.  */
+
−
+
−# include <thread.h>
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−
+
−# if USE_SOLARIS_THREADS_WEAK
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−
+
−/* Use weak references to the old Solaris threads library.  */
+
−
+
−#  pragma weak thr_keycreate
+
−#  pragma weak thr_getspecific
+
−#  pragma weak thr_setspecific
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−
+
−#  pragma weak thr_suspend
+
−#  define thread_in_use() (thr_suspend != NULL)
+
−
+
−# else
+
−
+
−#  define thread_in_use() 1
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−
+
−# endif
+
−
+
−/* ------------------------- gl_tls_key_t datatype ------------------------- */
+
−
+
−typedef union
+
−        {
+
−          void *singlethread_value;
+
−          thread_key_t key;
+
−        }
+
−        gl_tls_key_t;
+
−# define glthread_tls_key_init(KEY, DESTRUCTOR) \
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−    (thread_in_use ()                          \
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−     ? thr_keycreate (&(KEY)->key, DESTRUCTOR) \
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−     : ((KEY)->singlethread_value = NULL, 0))
+
−# define gl_tls_get(NAME) \
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−    (thread_in_use ()                \
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−     ? glthread_tls_get_multithreaded ((NAME).key) \
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−     : (NAME).singlethread_value)
+
−extern void *glthread_tls_get_multithreaded (thread_key_t key);
+
−# define glthread_tls_set(KEY, POINTER) \
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−    (thread_in_use ()                              \
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−     ? thr_setspecific ((KEY)->key, (POINTER))     \
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−     : ((KEY)->singlethread_value = (POINTER), 0))
+
−# define glthread_tls_key_destroy(KEY) \
+
−    /* Unsupported.  */ \
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−    0
+
−
+
−#endif
+
−
+
−/* ========================================================================= */
+
−
+
−#if USE_WINDOWS_THREADS
+
−
+
−# define WIN32_LEAN_AND_MEAN  /* avoid including junk */
+
−# include <windows.h>
+
−
+
−/* ------------------------- gl_tls_key_t datatype ------------------------- */
+
−
+
−typedef DWORD gl_tls_key_t;
+
−# define glthread_tls_key_init(KEY, DESTRUCTOR) \
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−    /* The destructor is unsupported.  */    \
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−    ((*(KEY) = TlsAlloc ()) == (DWORD)-1 ? EAGAIN : ((void) (DESTRUCTOR), 0))
+
−# define gl_tls_get(NAME) \
+
−    TlsGetValue (NAME)
+
−# define glthread_tls_set(KEY, POINTER) \
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−    (!TlsSetValue (*(KEY), POINTER) ? EINVAL : 0)
+
−# define glthread_tls_key_destroy(KEY) \
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−    (!TlsFree (*(KEY)) ? EINVAL : 0)
+
−
+
−#endif
+
−
+
−/* ========================================================================= */
+
−
+
−#if !(USE_POSIX_THREADS || USE_PTH_THREADS || USE_SOLARIS_THREADS || USE_WINDOWS_THREADS)
+
−
+
−/* Provide dummy implementation if threads are not supported.  */
+
−
+
−/* ------------------------- gl_tls_key_t datatype ------------------------- */
+
−
+
−typedef struct
+
−        {
+
−          void *singlethread_value;
+
−        }
+
−        gl_tls_key_t;
+
−# define glthread_tls_key_init(KEY, DESTRUCTOR) \
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−    ((KEY)->singlethread_value = NULL, \
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−     (void) (DESTRUCTOR),              \
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−     0)
+
−# define gl_tls_get(NAME) \
+
−    (NAME).singlethread_value
+
−# define glthread_tls_set(KEY, POINTER) \
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−    ((KEY)->singlethread_value = (POINTER), 0)
+
−# define glthread_tls_key_destroy(KEY) \
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−    0
+
−
+
−#endif
+
−
+
−/* ========================================================================= */
+
−
+
−/* Macros with built-in error handling.  */
+
−
+
−/* ------------------------- gl_tls_key_t datatype ------------------------- */
+
−
+
−#define gl_tls_key_init(NAME, DESTRUCTOR) \
+
−   do                                                 \
+
−     {                                                \
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−       if (glthread_tls_key_init (&NAME, DESTRUCTOR)) \
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−         abort ();                                    \
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−     }                                                \
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−   while (0)
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−#define gl_tls_set(NAME, POINTER) \
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−   do                                         \
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−     {                                        \
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−       if (glthread_tls_set (&NAME, POINTER)) \
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−         abort ();                            \
+
−     }                                        \
+
−   while (0)
+
−#define gl_tls_key_destroy(NAME) \
+
−   do                                        \
+
−     {                                       \
+
−       if (glthread_tls_key_destroy (&NAME)) \
+
−         abort ();                           \
+
−     }                                       \
+
−   while (0)
+
−
+
−/* ========================================================================= */
+
−
+
−#endif /* _TLS_H */