libguile/threads.h

   1 /* classes: h_files */
   2
   3 #ifndef SCM_THREADS_H
   4 #define SCM_THREADS_H
   5
   6 /* Copyright (C) 1996,1997,1998,2000,2001, 2002 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
  47 \f
  48
  49 #include "libguile/__scm.h"
  50 #include "libguile/procs.h"
  51 #include "libguile/throw.h"
  52 #include "libguile/root.h"
  53 #include "libguile/iselect.h"
  54 \f
  55
  56 /* smob tags for the thread datatypes */
  57 SCM_API scm_t_bits scm_tc16_thread;
  58 SCM_API scm_t_bits scm_tc16_mutex;
  59 SCM_API scm_t_bits scm_tc16_condvar;
  60
  61 #define SCM_THREADP(x)      SCM_TYP16_PREDICATE (scm_tc16_thread, x)
  62 #define SCM_THREAD_DATA(x)  ((void *) SCM_CELL_WORD_1 (x))
  63
  64 #define SCM_MUTEXP(x)       SCM_TYP16_PREDICATE (scm_tc16_mutex, x)
  65 #define SCM_MUTEX_DATA(x)   ((void *) SCM_CELL_WORD_1 (x))
  66
  67 #define SCM_CONDVARP(x)     SCM_TYP16_PREDICATE (scm_tc16_condvar, x)
  68 #define SCM_CONDVAR_DATA(x) ((void *) SCM_CELL_WORD_1 (x))
  69
  70 #define SCM_VALIDATE_THREAD(pos, a) \
  71  SCM_MAKE_VALIDATE_MSG (pos, a, THREADP, "thread")
  72
  73 #define SCM_VALIDATE_MUTEX(pos, a) \
  74  SCM_MAKE_VALIDATE_MSG (pos, a, MUTEXP, "mutex")
  75
  76 #define SCM_VALIDATE_CONDVAR(pos, a) \
  77  SCM_MAKE_VALIDATE_MSG (pos, a, CONDVARP, "condition variable")
  78
  79 SCM_API void scm_threads_mark_stacks (void);
  80 SCM_API void scm_init_threads (SCM_STACKITEM *);
  81 SCM_API void scm_init_thread_procs (void);
  82
  83 SCM_API SCM scm_spawn_thread (scm_t_catch_body body, void *body_data,
  84                               scm_t_catch_handler handler, void *handler_data);
  85
  86 /* These are versions of the ordinary sleep and usleep functions
  87    that play nicely with the thread system.  */
  88 SCM_API unsigned long scm_thread_sleep (unsigned long);
  89 SCM_API unsigned long scm_thread_usleep (unsigned long);
  90
  91 /* Critical sections */
  92
  93 /* Since only one thread can be active anyway, we don't need to do
  94    anything special around critical sections.  In fact, that's the
  95    reason we do only support cooperative threading: Guile's critical
  96    regions have not been completely identified yet.  (I think.) */
  97
  98 #define SCM_CRITICAL_SECTION_START
  99 #define SCM_CRITICAL_SECTION_END
 100
 101 /* Switching */
 102
 103 SCM_API int scm_i_switch_counter;
 104 #define SCM_I_THREAD_SWITCH_COUNT 50
 105
 106 #define SCM_THREAD_SWITCHING_CODE \
 107 do { \
 108   scm_i_switch_counter--; \
 109   if (scm_i_switch_counter == 0) \
 110     { \
 111       scm_i_switch_counter = SCM_I_THREAD_SWITCH_COUNT; \
 112       scm_yield(); \
 113     } \
 114 } while (0)
 115
 116 /* The C versions of the Scheme-visible thread functions.  */
 117 SCM_API SCM scm_yield (void);
 118 SCM_API SCM scm_call_with_new_thread (SCM thunk, SCM handler);
 119 SCM_API SCM scm_join_thread (SCM t);
 120 SCM_API SCM scm_make_mutex (void);
 121 SCM_API SCM scm_lock_mutex (SCM m);
 122 SCM_API SCM scm_try_mutex (SCM m);
 123 SCM_API SCM scm_unlock_mutex (SCM m);
 124 SCM_API SCM scm_make_condition_variable (void);
 125 SCM_API SCM scm_wait_condition_variable (SCM cond, SCM mutex);
 126 SCM_API SCM scm_timed_wait_condition_variable (SCM cond, SCM mutex,
 127                                                SCM abstime);
 128 SCM_API SCM scm_signal_condition_variable (SCM cond);
 129 SCM_API SCM scm_broadcast_condition_variable (SCM cond);
 130
 131 SCM_API SCM scm_current_thread (void);
 132 SCM_API SCM scm_all_threads (void);
 133
 134 SCM_API int scm_c_thread_exited_p (SCM thread);
 135 SCM_API SCM scm_thread_exited_p (SCM thread);
 136
 137 SCM_API scm_root_state *scm_i_thread_root (SCM thread);
 138
 139 SCM_API void *scm_i_thread_data;
 140 SCM_API void scm_i_set_thread_data (void *);
 141 #define SCM_THREAD_LOCAL_DATA        scm_i_thread_data
 142 #define SCM_SET_THREAD_LOCAL_DATA(x) scm_i_set_thread_data(x)
 143
 144 #ifndef HAVE_STRUCT_TIMESPEC
 145 /* POSIX.4 structure for a time value.  This is like a `struct timeval' but
 146    has nanoseconds instead of microseconds.  */
 147 struct timespec
 148 {
 149   long int tv_sec;              /* Seconds.  */
 150   long int tv_nsec;             /* Nanoseconds.  */
 151 };
 152 #endif
 153
 154 #ifdef USE_COPT_THREADS
 155 #include "libguile/pthread-threads.h"
 156 #else
 157 #include "libguile/null-threads.h"
 158 #endif
 159
 160 #endif  /* SCM_THREADS_H */
 161
 162 /*
 163   Local Variables:
 164   c-file-style: "gnu"
 165   End:
 166 */