/* 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. */ int scm_i_plugin_mutex_size = 0; int (*scm_i_plugin_mutex_init) (scm_t_mutex *, const scm_t_mutexattr *); int (*scm_i_plugin_mutex_lock) (scm_t_mutex *); int (*scm_i_plugin_mutex_unlock) (scm_t_mutex *); int scm_i_plugin_rec_mutex_size = 0; int (*scm_i_plugin_rec_mutex_init) (scm_t_rec_mutex *, const scm_t_mutexattr *); int (*scm_i_plugin_rec_mutex_destroy) (scm_t_rec_mutex *); int (*scm_i_plugin_rec_mutex_lock) (scm_t_rec_mutex *); int (*scm_i_plugin_rec_mutex_trylock) (scm_t_rec_mutex *); int (*scm_i_plugin_rec_mutex_unlock) (scm_t_rec_mutex *); int (*scm_i_plugin_cond_wait) (scm_t_cond *, scm_t_mutex *); int (*scm_i_plugin_cond_timedwait) (scm_t_cond *, scm_t_mutex *, const struct timespec *); 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; static int 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; } static int rec_mutex_destroy (scm_t_rec_mutex *mx) { rec_mutex *m = (rec_mutex *) mx; return scm_i_plugin_mutex_destroy (&m->mutex); } static int 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; } static int 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; } static int 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; } #ifndef SCM_MUTEXATTR_SETTYPE_DECLARED int pthread_mutexattr_settype (pthread_mutexattr_t *, int); #endif void scm_init_threads_plugin () { if (scm_i_plugin_rec_mutex_size == 0) { scm_i_plugin_rec_mutex_size = sizeof (rec_mutex); scm_i_plugin_mutex_init (&rec_mutex_mutex, &scm_i_plugin_mutex); scm_i_plugin_rec_mutex_init = rec_mutex_init; scm_i_plugin_rec_mutex_destroy = rec_mutex_destroy; scm_i_plugin_rec_mutex_lock = rec_mutex_lock; scm_i_plugin_rec_mutex_trylock = rec_mutex_trylock; scm_i_plugin_rec_mutex_unlock = rec_mutex_unlock; } if (scm_i_plugin_mutex_size > SCM_MUTEX_MAXSIZE || scm_i_plugin_rec_mutex_size > SCM_REC_MUTEX_MAXSIZE) { fprintf (stderr, "Internal error: Need to upgrade mutex size\n"); abort (); } }