1/* GNU Objective C Runtime Thread Interface
2   Copyright (C) 1996, 1997 Free Software Foundation, Inc.
3   Contributed by Galen C. Hunt (gchunt@cs.rochester.edu)
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under the
8terms of the GNU General Public License as published by the Free Software
9Foundation; either version 2, or (at your option) any later version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
13FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
14details.
15
16You should have received a copy of the GNU General Public License along with
17GCC; see the file COPYING.  If not, write to the Free Software
18Foundation, 51 Franklin Street, Fifth Floor,
19Boston, MA 02110-1301, USA.  */
20
21/* As a special exception, if you link this library with files compiled with
22   GCC to produce an executable, this does not cause the resulting executable
23   to be covered by the GNU General Public License. This exception does not
24   however invalidate any other reasons why the executable file might be
25   covered by the GNU General Public License.  */
26
27#include <pthread.h>
28#include "objc/thr.h"
29#include "objc/runtime.h"
30
31/* Key structure for maintaining thread specific storage */
32static pthread_key_t _objc_thread_storage;
33
34/* Backend initialization functions */
35
36/* Initialize the threads subsystem. */
37int
38__objc_init_thread_system(void)
39{
40  /* Initialize the thread storage key */
41  return pthread_keycreate(&_objc_thread_storage, NULL);
42}
43
44/* Close the threads subsystem. */
45int
46__objc_close_thread_system(void)
47{
48  /* Destroy the thread storage key */
49  /* Not implemented yet */
50  /* return pthread_key_delete(&_objc_thread_storage); */
51  return 0;
52}
53
54/* Backend thread functions */
55
56/* Create a new thread of execution. */
57objc_thread_t
58__objc_thread_detach(void (*func)(void *arg), void *arg)
59{
60  objc_thread_t thread_id;
61  pthread_t new_thread_handle;
62
63  if (pthread_create(&new_thread_handle, pthread_attr_default,
64		     (void *)func, arg) == 0)
65    {
66      /* ??? May not work! (64bit) */
67      thread_id = *(objc_thread_t *)&new_thread_handle;
68      pthread_detach(&new_thread_handle);     /* Fully detach thread.     */
69    }
70  else
71    thread_id = NULL;
72
73  return thread_id;
74}
75
76/* Set the current thread's priority. */
77int
78__objc_thread_set_priority(int priority)
79{
80  int sys_priority = 0;
81
82  switch (priority)
83    {
84    case OBJC_THREAD_INTERACTIVE_PRIORITY:
85      sys_priority = (PRI_FG_MIN_NP + PRI_FG_MAX_NP) / 2;
86      break;
87    default:
88    case OBJC_THREAD_BACKGROUND_PRIORITY:
89      sys_priority = (PRI_BG_MIN_NP + PRI_BG_MAX_NP) / 2;
90      break;
91    case OBJC_THREAD_LOW_PRIORITY:
92      sys_priority = (PRI_BG_MIN_NP + PRI_BG_MAX_NP) / 2;
93      break;
94    }
95
96  /* Change the priority. */
97  if (pthread_setprio(pthread_self(), sys_priority) >= 0)
98    return 0;
99  else
100    /* Failed */
101    return -1;
102}
103
104/* Return the current thread's priority. */
105int
106__objc_thread_get_priority(void)
107{
108  int sys_priority;
109
110  if ((sys_priority = pthread_getprio(pthread_self())) >= 0) {
111    if (sys_priority >= PRI_FG_MIN_NP && sys_priority <= PRI_FG_MAX_NP)
112      return OBJC_THREAD_INTERACTIVE_PRIORITY;
113    if (sys_priority >= PRI_BG_MIN_NP && sys_priority <= PRI_BG_MAX_NP)
114      return OBJC_THREAD_BACKGROUND_PRIORITY;
115    return OBJC_THREAD_LOW_PRIORITY;
116  }
117
118  /* Failed */
119  return -1;
120}
121
122/* Yield our process time to another thread. */
123void
124__objc_thread_yield(void)
125{
126  pthread_yield();
127}
128
129/* Terminate the current thread. */
130int
131__objc_thread_exit(void)
132{
133  /* exit the thread */
134  pthread_exit(&__objc_thread_exit_status);
135
136  /* Failed if we reached here */
137  return -1;
138}
139
140/* Returns an integer value which uniquely describes a thread. */
141objc_thread_t
142__objc_thread_id(void)
143{
144  pthread_t self = pthread_self();
145
146  return (objc_thread_t) pthread_getunique_np (&self);
147}
148
149/* Sets the thread's local storage pointer. */
150int
151__objc_thread_set_data(void *value)
152{
153  return pthread_setspecific(_objc_thread_storage, value);
154}
155
156/* Returns the thread's local storage pointer. */
157void *
158__objc_thread_get_data(void)
159{
160  void *value = NULL;
161
162  if ( !(pthread_getspecific(_objc_thread_storage, &value)) )
163    return value;
164
165  return NULL;
166}
167
168/* Backend mutex functions */
169
170/* Allocate a mutex. */
171int
172__objc_mutex_allocate(objc_mutex_t mutex)
173{
174  if (pthread_mutex_init((pthread_mutex_t *)(&(mutex->backend)),
175			 pthread_mutexattr_default))
176    return -1;
177  else
178    return 0;
179}
180
181/* Deallocate a mutex. */
182int
183__objc_mutex_deallocate(objc_mutex_t mutex)
184{
185  if (pthread_mutex_destroy((pthread_mutex_t *)(&(mutex->backend))))
186    return -1;
187  else
188    return 0;
189}
190
191/* Grab a lock on a mutex. */
192int
193__objc_mutex_lock(objc_mutex_t mutex)
194{
195  return pthread_mutex_lock((pthread_mutex_t *)(&(mutex->backend)));
196}
197
198/* Try to grab a lock on a mutex. */
199int
200__objc_mutex_trylock(objc_mutex_t mutex)
201{
202  if (pthread_mutex_trylock((pthread_mutex_t *)(&(mutex->backend))) != 1)
203    return -1;
204  else
205    return 0;
206}
207
208/* Unlock the mutex */
209int
210__objc_mutex_unlock(objc_mutex_t mutex)
211{
212  return pthread_mutex_unlock((pthread_mutex_t *)(&(mutex->backend)));
213}
214
215/* Backend condition mutex functions */
216
217/* Allocate a condition. */
218int
219__objc_condition_allocate(objc_condition_t condition)
220{
221  /* Unimplemented. */
222  return -1;
223
224  /*
225  if (pthread_cond_init((pthread_cond_t *)(&(condition->backend)), NULL))
226    return -1;
227  else
228    return 0;
229    */
230}
231
232/* Deallocate a condition. */
233int
234__objc_condition_deallocate(objc_condition_t condition)
235{
236  /* Unimplemented. */
237  return -1;
238
239  /*
240  return pthread_cond_destroy((pthread_cond_t *)(&(condition->backend)));
241  */
242}
243
244/* Wait on the condition */
245int
246__objc_condition_wait(objc_condition_t condition, objc_mutex_t mutex)
247{
248  /* Unimplemented. */
249  return -1;
250
251  /*
252  return pthread_cond_wait((pthread_cond_t *)(&(condition->backend)),
253			   (pthread_mutex_t *)(&(mutex->backend)));
254			   */
255}
256
257/* Wake up all threads waiting on this condition. */
258int
259__objc_condition_broadcast(objc_condition_t condition)
260{
261  /* Unimplemented. */
262  return -1;
263
264  /*
265  return pthread_cond_broadcast((pthread_cond_t *)(&(condition->backend)));
266  */
267}
268
269/* Wake up one thread waiting on this condition. */
270int
271__objc_condition_signal(objc_condition_t condition)
272{
273  /* Unimplemented. */
274  return -1;
275
276  /*
277  return pthread_cond_signal((pthread_cond_t *)(&(condition->backend)));
278  */
279}
280
281/* End of File */
282