u_thread.h revision a2f28ceea22254f09ee37039eec873ccdf689e6c 
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.5.2
4 *
5 * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25
26/*
27 * Thread support for gl dispatch.
28 *
29 * Initial version by John Stone (j.stone@acm.org) (johns@cs.umr.edu)
30 *                and Christoph Poliwoda (poliwoda@volumegraphics.com)
31 * Revised by Keith Whitwell
32 * Adapted for new gl dispatcher by Brian Paul
33 * Modified for use in mapi by Chia-I Wu
34 */
35
36/*
37 * If this file is accidentally included by a non-threaded build,
38 * it should not cause the build to fail, or otherwise cause problems.
39 * In general, it should only be included when needed however.
40 */
41
42#ifndef _U_THREAD_H_
43#define _U_THREAD_H_
44
45#include <stdio.h>
46#include <stdlib.h>
47#include "u_compiler.h"
48
49#if defined(HAVE_PTHREAD)
50#include <pthread.h> /* POSIX threads headers */
51#endif
52#ifdef _WIN32
53#include <windows.h>
54#endif
55
56#if defined(HAVE_PTHREAD) || defined(_WIN32)
57#ifndef THREADS
58#define THREADS
59#endif
60#endif
61
62/*
63 * Error messages
64 */
65#define INIT_TSD_ERROR "_glthread_: failed to allocate key for thread specific data"
66#define GET_TSD_ERROR "_glthread_: failed to get thread specific data"
67#define SET_TSD_ERROR "_glthread_: thread failed to set thread specific data"
68
69
70/*
71 * Magic number to determine if a TSD object has been initialized.
72 * Kind of a hack but there doesn't appear to be a better cross-platform
73 * solution.
74 */
75#define INIT_MAGIC 0xff8adc98
76
77#ifdef __cplusplus
78extern "C" {
79#endif
80
81
82/*
83 * POSIX threads. This should be your choice in the Unix world
84 * whenever possible.  When building with POSIX threads, be sure
85 * to enable any compiler flags which will cause the MT-safe
86 * libc (if one exists) to be used when linking, as well as any
87 * header macros for MT-safe errno, etc.  For Solaris, this is the -mt
88 * compiler flag.  On Solaris with gcc, use -D_REENTRANT to enable
89 * proper compiling for MT-safe libc etc.
90 */
91#if defined(HAVE_PTHREAD)
92
93struct u_tsd {
94   pthread_key_t key;
95   unsigned initMagic;
96};
97
98typedef pthread_mutex_t u_mutex;
99
100#define u_mutex_declare_static(name) \
101   static u_mutex name = PTHREAD_MUTEX_INITIALIZER
102
103#define u_mutex_init(name)    pthread_mutex_init(&(name), NULL)
104#define u_mutex_destroy(name) pthread_mutex_destroy(&(name))
105#define u_mutex_lock(name)    (void) pthread_mutex_lock(&(name))
106#define u_mutex_unlock(name)  (void) pthread_mutex_unlock(&(name))
107
108static INLINE unsigned long
109u_thread_self(void)
110{
111   return (unsigned long) pthread_self();
112}
113
114
115static INLINE void
116u_tsd_init(struct u_tsd *tsd)
117{
118   if (pthread_key_create(&tsd->key, NULL/*free*/) != 0) {
119      perror(INIT_TSD_ERROR);
120      exit(-1);
121   }
122   tsd->initMagic = INIT_MAGIC;
123}
124
125
126static INLINE void *
127u_tsd_get(struct u_tsd *tsd)
128{
129   if (tsd->initMagic != INIT_MAGIC) {
130      u_tsd_init(tsd);
131   }
132   return pthread_getspecific(tsd->key);
133}
134
135
136static INLINE void
137u_tsd_set(struct u_tsd *tsd, void *ptr)
138{
139   if (tsd->initMagic != INIT_MAGIC) {
140      u_tsd_init(tsd);
141   }
142   if (pthread_setspecific(tsd->key, ptr) != 0) {
143      perror(SET_TSD_ERROR);
144      exit(-1);
145   }
146}
147
148#endif /* HAVE_PTHREAD */
149
150
151/*
152 * Windows threads. Should work with Windows NT and 95.
153 * IMPORTANT: Link with multithreaded runtime library when THREADS are
154 * used!
155 */
156#ifdef WIN32
157
158struct u_tsd {
159   DWORD key;
160   unsigned initMagic;
161};
162
163typedef CRITICAL_SECTION u_mutex;
164
165/* http://locklessinc.com/articles/pthreads_on_windows/ */
166#define u_mutex_declare_static(name) \
167   static u_mutex name = {(PCRITICAL_SECTION_DEBUG)-1, -1, 0, 0, 0, 0}
168
169#define u_mutex_init(name)    InitializeCriticalSection(&name)
170#define u_mutex_destroy(name) DeleteCriticalSection(&name)
171#define u_mutex_lock(name)    EnterCriticalSection(&name)
172#define u_mutex_unlock(name)  LeaveCriticalSection(&name)
173
174static INLINE unsigned long
175u_thread_self(void)
176{
177   return GetCurrentThreadId();
178}
179
180
181static INLINE void
182u_tsd_init(struct u_tsd *tsd)
183{
184   tsd->key = TlsAlloc();
185   if (tsd->key == TLS_OUT_OF_INDEXES) {
186      perror(INIT_TSD_ERROR);
187      exit(-1);
188   }
189   tsd->initMagic = INIT_MAGIC;
190}
191
192
193static INLINE void
194u_tsd_destroy(struct u_tsd *tsd)
195{
196   if (tsd->initMagic != INIT_MAGIC) {
197      return;
198   }
199   TlsFree(tsd->key);
200   tsd->initMagic = 0x0;
201}
202
203
204static INLINE void *
205u_tsd_get(struct u_tsd *tsd)
206{
207   if (tsd->initMagic != INIT_MAGIC) {
208      u_tsd_init(tsd);
209   }
210   return TlsGetValue(tsd->key);
211}
212
213
214static INLINE void
215u_tsd_set(struct u_tsd *tsd, void *ptr)
216{
217   /* the following code assumes that the struct u_tsd has been initialized
218      to zero at creation */
219   if (tsd->initMagic != INIT_MAGIC) {
220      u_tsd_init(tsd);
221   }
222   if (TlsSetValue(tsd->key, ptr) == 0) {
223      perror(SET_TSD_ERROR);
224      exit(-1);
225   }
226}
227
228#endif /* WIN32 */
229
230
231/*
232 * THREADS not defined
233 */
234#ifndef THREADS
235
236struct u_tsd {
237   unsigned initMagic;
238};
239
240typedef unsigned u_mutex;
241
242#define u_mutex_declare_static(name)   static u_mutex name = 0
243#define u_mutex_init(name)             (void) name
244#define u_mutex_destroy(name)          (void) name
245#define u_mutex_lock(name)             (void) name
246#define u_mutex_unlock(name)           (void) name
247
248/*
249 * no-op functions
250 */
251
252static INLINE unsigned long
253u_thread_self(void)
254{
255   return 0;
256}
257
258
259static INLINE void
260u_tsd_init(struct u_tsd *tsd)
261{
262   (void) tsd;
263}
264
265
266static INLINE void *
267u_tsd_get(struct u_tsd *tsd)
268{
269   (void) tsd;
270   return NULL;
271}
272
273
274static INLINE void
275u_tsd_set(struct u_tsd *tsd, void *ptr)
276{
277   (void) tsd;
278   (void) ptr;
279}
280#endif /* THREADS */
281
282
283#ifdef __cplusplus
284}
285#endif
286
287#endif /* _U_THREAD_H_ */
288