src/mesa/glapi/glthread.h

/*
 * Mesa 3-D graphics library
 * Version:  6.3
 *
 * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */


/*
 * Thread support for gl dispatch.
 *
 * Initial version by John Stone (j.stone@acm.org) (johns@cs.umr.edu)
 *                and Christoph Poliwoda (poliwoda@volumegraphics.com)
 * Revised by Keith Whitwell
 * Adapted for new gl dispatcher by Brian Paul
 *
 *
 *
 * DOCUMENTATION
 *
 * This thread module exports the following types:
 *   _glthread_TSD     Thread-specific data area
 *   _glthread_Thread  Thread datatype
 *   _glthread_Mutex   Mutual exclusion lock
 *
 * Macros:
 *   _glthread_DECLARE_STATIC_MUTEX(name)   Declare a non-local mutex
 *   _glthread_INIT_MUTEX(name)             Initialize a mutex
 *   _glthread_LOCK_MUTEX(name)             Lock a mutex
 *   _glthread_UNLOCK_MUTEX(name)           Unlock a mutex
 *
 * Functions:
 *   _glthread_GetID(v)      Get integer thread ID
 *   _glthread_InitTSD()     Initialize thread-specific data
 *   _glthread_GetTSD()      Get thread-specific data
 *   _glthread_SetTSD()      Set thread-specific data
 *
 */

/*
 * If this file is accidentally included by a non-threaded build,
 * it should not cause the build to fail, or otherwise cause problems.
 * In general, it should only be included when needed however.
 */

#ifndef GLTHREAD_H
#define GLTHREAD_H


#if (defined(PTHREADS) || defined(SOLARIS_THREADS) ||\
     defined(WIN32_THREADS) || defined(USE_XTHREADS) || defined(BEOS_THREADS)) \
    && !defined(THREADS)
# define THREADS
#endif

#ifdef VMS
#include <GL/vms_x_fix.h>
#endif

/*
 * POSIX threads. This should be your choice in the Unix world
 * whenever possible.  When building with POSIX threads, be sure
 * to enable any compiler flags which will cause the MT-safe
 * libc (if one exists) to be used when linking, as well as any
 * header macros for MT-safe errno, etc.  For Solaris, this is the -mt
 * compiler flag.  On Solaris with gcc, use -D_REENTRANT to enable
 * proper compiling for MT-safe libc etc.
 */
#if defined(PTHREADS)
#include <pthread.h> /* POSIX threads headers */

typedef struct {
   pthread_key_t  key;
   int initMagic;
} _glthread_TSD;

typedef pthread_t _glthread_Thread;

typedef pthread_mutex_t _glthread_Mutex;

#define _glthread_DECLARE_STATIC_MUTEX(name) \
   static _glthread_Mutex name = PTHREAD_MUTEX_INITIALIZER

#define _glthread_INIT_MUTEX(name) \
   pthread_mutex_init(&(name), NULL)

#define _glthread_DESTROY_MUTEX(name) \
   pthread_mutex_destroy(&(name))

#define _glthread_LOCK_MUTEX(name) \
   (void) pthread_mutex_lock(&(name))

#define _glthread_UNLOCK_MUTEX(name) \
   (void) pthread_mutex_unlock(&(name))

/* This is temporarilly removed because driver binaries cannot count on
 * the existance of _gl_DispatchTSD in libGL.  It only exists in "new"
 * libGL.  We may be able to ressurect this optimization at some point
 * for DRI driver or for software Mesa.
 */
#if 0
extern struct _glapi_table * _glapi_DispatchTSD;
extern _glthread_TSD _gl_DispatchTSD;

#define GET_DISPATCH() \
   ((__builtin_expect( _glapi_DispatchTSD != NULL, 1 )) \
       ? _glapi_DispatchTSD : (struct _glapi_table *) pthread_getspecific(_gl_DispatchTSD.key))
#endif

#endif /* PTHREADS */




/*
 * Solaris threads. Use only up to Solaris 2.4.
 * Solaris 2.5 and higher provide POSIX threads.
 * Be sure to compile with -mt on the Solaris compilers, or
 * use -D_REENTRANT if using gcc.
 */
#ifdef SOLARIS_THREADS
#include <thread.h>

typedef struct {
   thread_key_t key;
   mutex_t      keylock;
   int          initMagic;
} _glthread_TSD;

typedef thread_t _glthread_Thread;

typedef mutex_t _glthread_Mutex;

/* XXX need to really implement mutex-related macros */
#define _glthread_DECLARE_STATIC_MUTEX(name)  static _glthread_Mutex name = 0
#define _glthread_INIT_MUTEX(name)  (void) name
#define _glthread_DESTROY_MUTEX(name) (void) name
#define _glthread_LOCK_MUTEX(name)  (void) name
#define _glthread_UNLOCK_MUTEX(name)  (void) name

#endif /* SOLARIS_THREADS */




/*
 * Windows threads. Should work with Windows NT and 95.
 * IMPORTANT: Link with multithreaded runtime library when THREADS are
 * used!
 */
#ifdef WIN32_THREADS
#include <windows.h>

typedef struct {
   DWORD key;
   int   initMagic;
} _glthread_TSD;

typedef HANDLE _glthread_Thread;

typedef CRITICAL_SECTION _glthread_Mutex;

/* XXX need to really implement mutex-related macros */
#define _glthread_DECLARE_STATIC_MUTEX(name)  static _glthread_Mutex name = 0
#define _glthread_INIT_MUTEX(name)  (void) name
#define _glthread_DESTROY_MUTEX(name)  (void) name
#define _glthread_LOCK_MUTEX(name)  (void) name
#define _glthread_UNLOCK_MUTEX(name)  (void) name

#endif /* WIN32_THREADS */




/*
 * XFree86 has its own thread wrapper, Xthreads.h
 * We wrap it again for GL.
 */
#ifdef USE_XTHREADS
#include <X11/Xthreads.h>

typedef struct {
   xthread_key_t key;
   int initMagic;
} _glthread_TSD;

typedef xthread_t _glthread_Thread;

typedef xmutex_rec _glthread_Mutex;

#ifdef XMUTEX_INITIALIZER
#define _glthread_DECLARE_STATIC_MUTEX(name) \
   static _glthread_Mutex name = XMUTEX_INITIALIZER
#else
#define _glthread_DECLARE_STATIC_MUTEX(name) \
   static _glthread_Mutex name
#endif

#define _glthread_INIT_MUTEX(name) \
   xmutex_init(&(name))

#define _glthread_DESTROY_MUTEX(name) \
   xmutex_clear(&(name))

#define _glthread_LOCK_MUTEX(name) \
   (void) xmutex_lock(&(name))

#define _glthread_UNLOCK_MUTEX(name) \
   (void) xmutex_unlock(&(name))

#endif /* USE_XTHREADS */



/*
 * BeOS threads. R5.x required.
 */
#ifdef BEOS_THREADS

#include <kernel/OS.h>
#include <support/TLS.h>

typedef struct {
   int32        key;
   int          initMagic;
} _glthread_TSD;

typedef thread_id _glthread_Thread;

/* Use Benaphore, aka speeder semaphore */
typedef struct {
    int32   lock;
    sem_id  sem;
} benaphore;
typedef benaphore _glthread_Mutex;

#define _glthread_DECLARE_STATIC_MUTEX(name)  static _glthread_Mutex name = { 0, 0 }
#define _glthread_INIT_MUTEX(name)    	name.sem = create_sem(0, #name"_benaphore"), name.lock = 0
#define _glthread_DESTROY_MUTEX(name) 	delete_sem(name.sem), name.lock = 0
#define _glthread_LOCK_MUTEX(name)    	if (name.sem == 0) _glthread_INIT_MUTEX(name); \
									  	if (atomic_add(&(name.lock), 1) >= 1) acquire_sem(name.sem)
#define _glthread_UNLOCK_MUTEX(name)  	if (atomic_add(&(name.lock), -1) > 1) release_sem(name.sem)

#endif /* BEOS_THREADS */



#ifndef THREADS

/*
 * THREADS not defined
 */

typedef GLuint _glthread_TSD;

typedef GLuint _glthread_Thread;

typedef GLuint _glthread_Mutex;

#define _glthread_DECLARE_STATIC_MUTEX(name)  static _glthread_Mutex name = 0

#define _glthread_INIT_MUTEX(name)  (void) name

#define _glthread_DESTROY_MUTEX(name)  (void) name

#define _glthread_LOCK_MUTEX(name)  (void) name

#define _glthread_UNLOCK_MUTEX(name)  (void) name

#endif /* THREADS */



/*
 * Platform independent thread specific data API.
 */

extern unsigned long
_glthread_GetID(void);


extern void
_glthread_InitTSD(_glthread_TSD *);


extern void *
_glthread_GetTSD(_glthread_TSD *);


extern void
_glthread_SetTSD(_glthread_TSD *, void *);

#if defined(GLX_USE_TLS)

extern __thread struct _glapi_table * _glapi_tls_Dispatch
    __attribute__((tls_model("initial-exec")));

#define GET_DISPATCH() _glapi_tls_Dispatch

#elif !defined(GL_CALL)
# if defined(THREADS)
extern struct _glapi_table * _glapi_DispatchTSD;
#  define GET_DISPATCH() \
   ((__builtin_expect( _glapi_DispatchTSD != NULL, 1 )) \
       ? _glapi_DispatchTSD : _glapi_get_dispatch())
# else
#  define GET_DISPATCH() _glapi_Dispatch
# endif /* defined(THREADS) */
#endif  /* ndef GL_CALL */


#endif /* THREADS_H */