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/* 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. */
# ifdef TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
# else
# ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
# else
# ifdef HAVE_TIME_H
# include <time.h>
# 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 \
{ \
if (scm_thread_count > 1) \
coop_yield(); \
} \
#else
#define SCM_THREAD_SWITCHING_CODE \
{ \
if (scm_thread_count > 1) \
{ \
scm_switch_counter--; \
if (scm_switch_counter == 0) \
{ \
scm_switch_counter = SCM_THREAD_SWITCH_COUNT; \
coop_yield(); \
} \
} \
} \
#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 */
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