/* classes: h_files */ #ifndef COOP_DEFSH #define COOP_DEFSH /* Copyright (C) 1996, 1997, 1998 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. */ /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999, gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */ # ifdef TIME_WITH_SYS_TIME # include # include # else # ifdef HAVE_SYS_TIME_H # include # else # ifdef HAVE_TIME_H # include # endif # endif # endif #ifdef GUILE_ISELECT #include "iselect.h" #endif /* This file is included by threads.h, which, in turn, is included by libguile.h while coop-threads.h only is included by coop-threads.c. */ /* The coop_t struct must be declared here, since macros in this file refer to the data member. */ /* The notion of a thread is merged with the notion of a queue. Thread stuff: thread status (sp) and stuff to use during (re)initialization. Queue stuff: next thread in the queue (next). */ struct qt_t; typedef struct coop_t { struct qt_t *sp; /* QuickThreads handle. */ void *sto; /* `malloc'-allocated stack. */ struct coop_t *next; /* Next thread in the queue. */ struct coop_t *all_next; struct coop_t *all_prev; void *data; /* Thread local data */ void *base; /* Base of stack */ void *top; /* Top of stack */ void *joining; /* A queue of threads waiting to join this thread */ #ifdef GUILE_ISELECT int nfds; SELECT_TYPE *readfds; SELECT_TYPE *writefds; SELECT_TYPE *exceptfds; int timeoutp; struct timeval wakeup_time; /* Time to stop sleeping */ int _errno; int retval; #else time_t wakeup_time; /* Time to stop sleeping */ #endif } coop_t; /* A queue is a circular list of threads. The queue head is a designated list element. If this is a uniprocessor-only implementation we can store the `main' thread in this, but in a multiprocessor there are several `heavy' threads but only one run queue. A fancier implementation might have private run queues, which would lead to a simpler (trivial) implementation */ typedef struct coop_q_t { coop_t t; coop_t *tail; } coop_q_t; /* A Mutex variable is made up of a owner thread, and a queue of threads waiting on the mutex */ typedef struct coop_m { coop_t *owner; /* Mutex owner */ coop_q_t waiting; /* Queue of waiting threads */ } coop_m; typedef coop_m scm_mutex_t; extern int coop_mutex_init (coop_m*); extern int coop_mutex_lock (coop_m*); extern int coop_mutex_unlock (coop_m*); extern int coop_mutex_destroy (coop_m*); #define scm_mutex_init coop_mutex_init #define scm_mutex_lock coop_mutex_lock #define scm_mutex_unlock coop_mutex_unlock #define scm_mutex_destroy coop_mutex_destroy /* A Condition variable is made up of a list of threads waiting on the condition. */ typedef struct coop_c { coop_q_t waiting; /* Queue of waiting threads */ } coop_c; typedef coop_c scm_cond_t; extern int coop_condition_variable_init (coop_c*); extern int coop_condition_variable_wait_mutex (coop_c*, coop_m*); extern int coop_condition_variable_signal (coop_c*); extern int coop_condition_variable_destroy (coop_c*); #define scm_cond_init(cond, attr) coop_condition_variable_init (cond) #define scm_cond_wait coop_condition_variable_wait_mutex #define scm_cond_signal coop_condition_variable_signal #define scm_cond_destroy coop_condition_variable_destroy extern coop_t *coop_global_curr; /* Currently-executing thread. */ extern void coop_join (coop_t *t); extern void coop_yield (void); extern size_t scm_switch_counter; extern size_t scm_thread_count; /* Some iselect functions. */ /* I'm not sure whether these three declarations should be here. They're really defined in iselect.c, so you'd think they'd go in iselect.h, but they use coop_t, defined above, which uses things defined in iselect.h. Basically, we're making at best a flailing (and failing) attempt at modularity here, and I don't have time to rethink this at the moment. This code awaits a Hero. --JimB */ extern coop_t *coop_next_runnable_thread (void); extern coop_t *coop_wait_for_runnable_thread_now (struct timeval *); extern coop_t *coop_wait_for_runnable_thread (void); /* Cooperative threads don't need to have these defined */ #define SCM_THREAD_CRITICAL_SECTION_START #define SCM_THREAD_CRITICAL_SECTION_END #define SCM_NO_CRITICAL_SECTION_OWNER 0 #define SCM_THREAD_SWITCH_COUNT 50 /* was 10 /mdj */ #define SCM_THREAD_DEFER #define SCM_THREAD_ALLOW #define SCM_THREAD_REDEFER #define SCM_THREAD_REALLOW_1 #define SCM_THREAD_REALLOW_2 #if 0 #define SCM_THREAD_SWITCHING_CODE \ do { \ if (scm_thread_count > 1) \ coop_yield(); \ } while (0) #else #define SCM_THREAD_SWITCHING_CODE \ do { \ if (scm_thread_count > 1) \ { \ scm_switch_counter--; \ if (scm_switch_counter == 0) \ { \ scm_switch_counter = SCM_THREAD_SWITCH_COUNT; \ coop_yield(); \ } \ } \ } while (0) #endif #define SCM_THREAD_LOCAL_DATA (coop_global_curr->data) #define SCM_SET_THREAD_LOCAL_DATA(ptr) (coop_global_curr->data = (ptr)) #endif /* COOP_DEFSH */