libguile/coop-defs.h

   1 /* classes: h_files */
   2
   3 #ifndef COOP_DEFSH
   4 #define COOP_DEFSH
   5
   6 /*      Copyright (C) 1996 Free Software Foundation, Inc.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2, or (at your option)
  11  * any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this software; see the file COPYING.  If not, write to
  20  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  21  * Boston, MA 02111-1307 USA
  22  *
  23  * As a special exception, the Free Software Foundation gives permission
  24  * for additional uses of the text contained in its release of GUILE.
  25  *
  26  * The exception is that, if you link the GUILE library with other files
  27  * to produce an executable, this does not by itself cause the
  28  * resulting executable to be covered by the GNU General Public License.
  29  * Your use of that executable is in no way restricted on account of
  30  * linking the GUILE library code into it.
  31  *
  32  * This exception does not however invalidate any other reasons why
  33  * the executable file might be covered by the GNU General Public License.
  34  *
  35  * This exception applies only to the code released by the
  36  * Free Software Foundation under the name GUILE.  If you copy
  37  * code from other Free Software Foundation releases into a copy of
  38  * GUILE, as the General Public License permits, the exception does
  39  * not apply to the code that you add in this way.  To avoid misleading
  40  * anyone as to the status of such modified files, you must delete
  41  * this exception notice from them.
  42  *
  43  * If you write modifications of your own for GUILE, it is your choice
  44  * whether to permit this exception to apply to your modifications.
  45  * If you do not wish that, delete this exception notice.  */
  46 \f
  47
  48 # ifdef TIME_WITH_SYS_TIME
  49 #  include <sys/time.h>
  50 #  include <time.h>
  51 # else
  52 #  ifdef HAVE_SYS_TIME_H
  53 #   include <sys/time.h>
  54 #  else
  55 #   ifdef HAVE_TIME_H
  56 #    include <time.h>
  57 #   endif
  58 #  endif
  59 # endif
  60
  61 #ifdef GUILE_ISELECT
  62 #include "iselect.h"
  63 #endif
  64
  65 /* This file is included by threads.h, which, in turn, is included by
  66    libguile.h while coop-threads.h only is included by
  67    coop-threads.c. */
  68
  69 /* The coop_t struct must be declared here, since macros in this file
  70    refer to the data member. */
  71
  72 /* The notion of a thread is merged with the notion of a queue.
  73    Thread stuff: thread status (sp) and stuff to use during
  74    (re)initialization.  Queue stuff: next thread in the queue
  75    (next). */
  76
  77 struct qt_t;
  78
  79 typedef struct coop_t {
  80   struct qt_t *sp;       /* QuickThreads handle. */
  81   void *sto;             /* `malloc'-allocated stack. */
  82
  83   struct coop_t *next;    /* Next thread in the queue. */
  84
  85   struct coop_t *all_next;
  86   struct coop_t *all_prev;
  87
  88   void *data;            /* Thread local data */
  89
  90   void *base;            /* Base of stack */
  91   void *top;             /* Top of stack */
  92
  93   void *joining;         /* A queue of threads waiting to join this
  94                             thread */
  95
  96 #ifdef GUILE_ISELECT
  97   int nfds;
  98   SELECT_TYPE *readfds;
  99   SELECT_TYPE *writefds;
 100   SELECT_TYPE *exceptfds;
 101   int timeoutp;
 102   struct timeval wakeup_time;   /* Time to stop sleeping */
 103   int _errno;
 104   int retval;
 105 #else
 106   time_t wakeup_time;    /* Time to stop sleeping */
 107 #endif
 108
 109 } coop_t;
 110
 111 extern coop_t *coop_global_curr;        /* Currently-executing thread. */
 112
 113 extern void coop_yield (void);
 114
 115 extern size_t scm_switch_counter;
 116 extern size_t scm_thread_count;
 117
 118 \f
 119
 120 /* Cooperative threads don't need to have these defined */
 121
 122 #define SCM_THREAD_CRITICAL_SECTION_START
 123 #define SCM_THREAD_CRITICAL_SECTION_END
 124
 125 \f
 126
 127 #define SCM_NO_CRITICAL_SECTION_OWNER 0
 128 #define SCM_THREAD_SWITCH_COUNT       50 /* was 10 /mdj */
 129
 130 \f
 131
 132 #define SCM_THREAD_DEFER
 133 #define SCM_THREAD_ALLOW
 134 #define SCM_THREAD_REDEFER
 135 #define SCM_THREAD_REALLOW_1
 136 #define SCM_THREAD_REALLOW_2
 137
 138 #if 0
 139 #define SCM_THREAD_SWITCHING_CODE \
 140 { \
 141   if (scm_thread_count > 1) \
 142     coop_yield(); \
 143 } \
 144
 145 #else
 146 #define SCM_THREAD_SWITCHING_CODE \
 147 { \
 148   if (scm_thread_count > 1) \
 149   { \
 150     scm_switch_counter--; \
 151     if (scm_switch_counter == 0) \
 152       { \
 153         scm_switch_counter = SCM_THREAD_SWITCH_COUNT; \
 154         coop_yield(); \
 155       } \
 156   } \
 157 } \
 158
 159 #endif
 160
 161 #define SCM_THREAD_LOCAL_DATA (coop_global_curr->data)
 162 #define SCM_SET_THREAD_LOCAL_DATA(ptr) (coop_global_curr->data = (ptr))
 163
 164 #endif /* COOP_DEFSH */