/* Copyright (C) 2002 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 2, 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 software; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307 USA * * As a special exception, the Free Software Foundation gives permission * for additional uses of the text contained in its release of GUILE. * * The exception is that, if you link the GUILE library with other files * to produce an executable, this does not by itself cause the * resulting executable to be covered by the GNU General Public License. * Your use of that executable is in no way restricted on account of * linking the GUILE library code into it. * * This exception does not however invalidate any other reasons why * the executable file might be covered by the GNU General Public License. * * This exception applies only to the code released by the * Free Software Foundation under the name GUILE. If you copy * code from other Free Software Foundation releases into a copy of * GUILE, as the General Public License permits, the exception does * not apply to the code that you add in this way. To avoid misleading * anyone as to the status of such modified files, you must delete * this exception notice from them. * * If you write modifications of your own for GUILE, it is your choice * whether to permit this exception to apply to your modifications. * If you do not wish that, delete this exception notice. */ #include "libguile/scmconfig.h" scm_t_mutexattr scm_i_plugin_mutex; scm_t_mutexattr scm_i_plugin_rec_mutex; #if !defined (SCM_MUTEX_RECURSIVE) || defined (SCM_DEBUG_THREADS) typedef struct rec_mutex { #ifdef SCM_DEBUG_THREADS int kind; #endif scm_t_mutex mutex; scm_thread *owner; int count; } rec_mutex; /* Mutex for recursive mutex administration */ static scm_t_mutex rec_mutex_mutex; #ifdef SCM_DEBUG_THREADS #define FAST_MUTEX 1 #define REC_MUTEX 2 typedef struct mutex { int kind; pthread_mutex_t mutex; scm_thread *owner; int count; } mutex; static pthread_mutex_t mutex_mutex; int scm_i_plugin_mutex_init (scm_t_mutex *mx, const scm_t_mutexattr *a) { mutex *m = (mutex *) mx; pthread_mutex_init (&m->mutex, &scm_i_plugin_mutex); m->owner = 0; m->count = 0; m->kind = FAST_MUTEX; return 0; } int scm_i_plugin_mutex_lock (scm_t_mutex *mx) { mutex *m = (mutex *) mx; scm_thread *t = SCM_CURRENT_THREAD; pthread_mutex_lock (&mutex_mutex); if (m->kind != FAST_MUTEX) { fprintf (stderr, m->kind == REC_MUTEX ? "locking wrong mutex type\n" : "locking uninitialized mutex\n"); abort (); } if (m->owner == t) { fprintf (stderr, "locking mutex already locked by self\n"); abort (); } pthread_mutex_unlock (&mutex_mutex); pthread_mutex_lock (&m->mutex); m->count = 1; m->owner = t; return 0; } int scm_i_plugin_mutex_unlock (scm_t_mutex *mx) { mutex *m = (mutex *) mx; pthread_mutex_lock (&mutex_mutex); if (m->kind != FAST_MUTEX) { fprintf (stderr, m->kind == REC_MUTEX ? "locking wrong mutex type\n" : "locking uninitialized mutex\n"); abort (); } if (m->count != 1) { fprintf (stderr, m->count == 0 ? "unlocking unlocked mutex\n" : "bogus internal state"); abort (); } m->owner = 0; m->count = 0; pthread_mutex_unlock (&m->mutex); pthread_mutex_unlock (&mutex_mutex); return 0; } int scm_i_plugin_cond_wait (scm_t_cond *c, scm_t_mutex *mx) { mutex *m = (mutex *) mx; int res; if (m->owner != SCM_CURRENT_THREAD || m->count != 1) { fprintf (stderr, "mutex not locked by self\n"); abort (); } res = pthread_cond_wait ((pthread_cond_t *) c, &m->mutex); if (m->owner != 0 || m->count != 0) { fprintf (stderr, "strange internal state\n"); abort (); } m->owner = SCM_CURRENT_THREAD; m->count = 1; return res; } int scm_i_plugin_cond_timedwait (scm_t_cond *c, scm_t_mutex *mx, const struct timespec *t) { mutex *m = (mutex *) mx; return pthread_cond_timedwait ((pthread_cond_t *) c, &m->mutex, t); } void scm_i_assert_heap_locked () { mutex *m = (mutex *) &SCM_CURRENT_THREAD->heap_mutex; pthread_mutex_lock (&mutex_mutex); if (gc_running) { fprintf (stderr, "thread running during gc\n"); abort (); } if (m->count != 1) { fprintf (stderr, "mutex not locked\n"); abort (); } pthread_mutex_unlock (&mutex_mutex); } #endif /* The following section belongs in threads.c, or rather thread-plugin.c. It is generic and not tied to any particular thread library. */ int scm_i_plugin_rec_mutex_init (scm_t_rec_mutex *mx, const scm_t_mutexattr *a) { rec_mutex *m = (rec_mutex *) mx; scm_i_plugin_mutex_init (&m->mutex, &scm_i_plugin_mutex); m->owner = 0; m->count = 0; #ifdef SCM_DEBUG_THREADS m->kind = REC_MUTEX; #endif return 0; } int scm_i_plugin_rec_mutex_lock (scm_t_rec_mutex *mx) { rec_mutex *m = (rec_mutex *) mx; scm_thread *t = SCM_CURRENT_THREAD; scm_i_plugin_mutex_lock (&rec_mutex_mutex); #ifdef SCM_DEBUG_THREADS if (m->kind != REC_MUTEX) { fprintf (stderr, m->kind == FAST_MUTEX ? "locking wrong mutex type\n" : "locking uninitialized mutex\n"); abort (); } #endif if (m->count && m->owner == t) { ++m->count; scm_i_plugin_mutex_unlock (&rec_mutex_mutex); } else { scm_i_plugin_mutex_unlock (&rec_mutex_mutex); scm_i_plugin_mutex_lock (&m->mutex); m->count = 1; m->owner = t; } return 0; } int scm_i_plugin_rec_mutex_trylock (scm_t_rec_mutex *mx) { rec_mutex *m = (rec_mutex *) mx; scm_thread *t = SCM_CURRENT_THREAD; scm_i_plugin_mutex_lock (&rec_mutex_mutex); if (m->owner != 0 && m->owner != t) return EBUSY; else if (m->count) { ++m->count; scm_i_plugin_mutex_unlock (&rec_mutex_mutex); } else { scm_i_plugin_mutex_unlock (&rec_mutex_mutex); scm_i_plugin_mutex_lock (&m->mutex); m->count = 1; m->owner = t; } return 0; } int scm_i_plugin_rec_mutex_unlock (scm_t_rec_mutex *mx) { rec_mutex *m = (rec_mutex *) mx; scm_i_plugin_mutex_lock (&rec_mutex_mutex); #ifdef SCM_DEBUG_THREADS if (m->kind != REC_MUTEX) { fprintf (stderr, m->kind == FAST_MUTEX ? "locking wrong mutex type\n" : "locking uninitialized mutex\n"); abort (); } if (m->count == 0) { fprintf (stderr, "unlocking unlocked mutex\n"); abort (); } #endif if (!--m->count) { m->owner = 0; scm_i_plugin_mutex_unlock (&m->mutex); } scm_i_plugin_mutex_unlock (&rec_mutex_mutex); return 0; } #endif /* !PTHREAD_MUTEX_RECURSIVE */ #ifndef SCM_MUTEXATTR_SETTYPE_DECLARED int pthread_mutexattr_settype (pthread_mutexattr_t *, int); #endif void scm_init_pthread_threads () { size_t mutex_size, rec_mutex_size; pthread_mutexattr_init (&scm_i_plugin_mutex); #ifdef SCM_MUTEX_FAST pthread_mutexattr_settype (&scm_i_plugin_mutex, SCM_MUTEX_FAST); #endif #if defined (SCM_MUTEX_RECURSIVE) && !defined (SCM_DEBUG_THREADS) rec_mutex_size = sizeof (pthread_mutex_t); pthread_mutexattr_init (&scm_i_plugin_rec_mutex); pthread_mutexattr_settype (&scm_i_plugin_rec_mutex, SCM_MUTEX_RECURSIVE); #else /* If PTHREAD_MUTEX_RECURSIVE is not defined, scm_i_plugin_rec_mutex_init won't pay attention to it anyway */ rec_mutex_size = sizeof (rec_mutex); scm_i_plugin_mutex_init (&rec_mutex_mutex, &scm_i_plugin_mutex); #endif #ifdef SCM_DEBUG_THREADS mutex_size = sizeof (mutex); pthread_mutex_init (&mutex_mutex, &scm_i_plugin_mutex); #else mutex_size = sizeof (pthread_mutex_t); #endif if (mutex_size > SCM_MUTEX_MAXSIZE || rec_mutex_size > SCM_REC_MUTEX_MAXSIZE) { fprintf (stderr, "Internal error: Need to upgrade mutex size\n"); abort (); } } /* Local Variables: c-file-style: "gnu" End: */