libguile/hooks.h

   1 /* classes: h_files */
   2
   3 #ifndef HOOKSH
   4 #define HOOKSH
   5 /*      Copyright (C) 1995, 1996, 1999, 2000 Free Software Foundation, Inc.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2, or (at your option)
  10  * any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this software; see the file COPYING.  If not, write to
  19  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  20  * Boston, MA 02111-1307 USA
  21  *
  22  * As a special exception, the Free Software Foundation gives permission
  23  * for additional uses of the text contained in its release of GUILE.
  24  *
  25  * The exception is that, if you link the GUILE library with other files
  26  * to produce an executable, this does not by itself cause the
  27  * resulting executable to be covered by the GNU General Public License.
  28  * Your use of that executable is in no way restricted on account of
  29  * linking the GUILE library code into it.
  30  *
  31  * This exception does not however invalidate any other reasons why
  32  * the executable file might be covered by the GNU General Public License.
  33  *
  34  * This exception applies only to the code released by the
  35  * Free Software Foundation under the name GUILE.  If you copy
  36  * code from other Free Software Foundation releases into a copy of
  37  * GUILE, as the General Public License permits, the exception does
  38  * not apply to the code that you add in this way.  To avoid misleading
  39  * anyone as to the status of such modified files, you must delete
  40  * this exception notice from them.
  41  *
  42  * If you write modifications of your own for GUILE, it is your choice
  43  * whether to permit this exception to apply to your modifications.
  44  * If you do not wish that, delete this exception notice.  */
  45
  46 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  47    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  48 \f
  49
  50 #include "libguile/__scm.h"
  51
  52 /*
  53  * C level hooks
  54  */
  55
  56 /*
  57  * The interface is designed for and- and or-type hooks which
  58  * both may want to indicate success/failure and return a result.
  59  */
  60
  61 typedef enum scm_c_hook_type_t {
  62   SCM_C_HOOK_NORMAL,
  63   SCM_C_HOOK_OR,
  64   SCM_C_HOOK_AND
  65 } scm_c_hook_type_t;
  66
  67 typedef void  *(*scm_c_hook_function_t) (void *hook_data,
  68                                          void *func_data,
  69                                          void *data);
  70
  71 typedef struct scm_c_hook_entry_t {
  72   struct scm_c_hook_entry_t *next;
  73   scm_c_hook_function_t func;
  74   void *data;
  75 } scm_c_hook_entry_t;
  76
  77 typedef struct scm_c_hook_t {
  78   scm_c_hook_entry_t *first;
  79   scm_c_hook_type_t type;
  80   void *data;
  81 } scm_c_hook_t;
  82
  83 extern void scm_c_hook_init (scm_c_hook_t *hook,
  84                              void *hook_data,
  85                              scm_c_hook_type_t type);
  86 extern void scm_c_hook_add (scm_c_hook_t *hook,
  87                             scm_c_hook_function_t func,
  88                             void *func_data,
  89                             int appendp);
  90 extern void scm_c_hook_remove (scm_c_hook_t *hook,
  91                                scm_c_hook_function_t func,
  92                                void *func_data);
  93 extern void *scm_c_hook_run (scm_c_hook_t *hook, void *data);
  94
  95 /*
  96  * Scheme level hooks
  97  */
  98
  99 extern scm_bits_t scm_tc16_hook;
 100
 101 #define SCM_HOOKP(x)                    SCM_TYP16_PREDICATE (scm_tc16_hook, x)
 102 #define SCM_HOOK_ARITY(hook)            (SCM_CELL_WORD_0 (hook) >> 16)
 103 #define SCM_HOOK_PROCEDURES(hook)       SCM_CELL_OBJECT_1 (hook)
 104 #define SCM_SET_HOOK_PROCEDURES(hook, procs) SCM_SET_CELL_OBJECT_1 ((hook), (procs))
 105
 106 extern SCM scm_make_hook (SCM n_args);
 107 extern SCM scm_create_hook (const char* name, int n_args);
 108 extern SCM scm_hook_p (SCM x);
 109 extern SCM scm_hook_empty_p (SCM hook);
 110 extern SCM scm_add_hook_x (SCM hook, SCM thunk, SCM appendp);
 111 extern SCM scm_remove_hook_x (SCM hook, SCM thunk);
 112 extern SCM scm_reset_hook_x (SCM hook);
 113 extern SCM scm_run_hook (SCM hook, SCM args);
 114 extern void scm_c_run_hook (SCM hook, SCM args);
 115 extern SCM scm_hook_to_list (SCM hook);
 116 extern void scm_init_hooks (void);
 117
 118 \f
 119
 120 #if (SCM_DEBUG_DEPRECATED == 0)
 121
 122 /* Use scm_set_object_property_x to set the name property of a hook: */
 123 #define SCM_HOOK_NAME(h) scm_object_property (h, scm_makfrom0str ("name"))
 124 extern SCM scm_make_hook_with_name (SCM name, SCM n_args);
 125
 126 #endif  /* SCM_DEBUG_DEPRECATED == 0 */
 127
 128 #endif  /* HOOKSH */
 129
 130 /*
 131   Local Variables:
 132   c-file-style: "gnu"
 133   End:
 134 */