set-hooks.h

   1 /* Macros for using symbol sets for running lists of functions.
   2 Copyright (C) 1994 Free Software Foundation, Inc.
   3 This file is part of the GNU C Library.
   4
   5 The GNU C Library is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU Library General Public License as
   7 published by the Free Software Foundation; either version 2 of the
   8 License, or (at your option) any later version.
   9
  10 The GNU C Library is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 Library General Public License for more details.
  14
  15 You should have received a copy of the GNU Library General Public
  16 License along with the GNU C Library; see the file COPYING.LIB.  If
  17 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  18 Cambridge, MA 02139, USA.  */
  19
  20 #ifndef _SET_HOOKS_H
  21
  22 #define __need_size_t
  23 #include <stddef.h>
  24 #include <sys/cdefs.h>
  25
  26 /* Define a hook variable called NAME.  Functions put on this hook take
  27    arguments described by PROTO.  Use `text_set_element (NAME, FUNCTION)'
  28    from gnu-stabs.h to add a function to the hook.  */
  29
  30 #define DEFINE_HOOK(NAME, PROTO) \
  31 const struct                                                                  \
  32   {                                                                           \
  33     size_t n;                                                                 \
  34     void (*fn[0]) __P (PROTO);                                                \
  35   } NAME
  36
  37 /* Run all the functions hooked on the set called NAME.
  38    Each function is called like this: `function ARGS'.  */
  39
  40 #define RUN_HOOK(NAME, ARGS) \
  41 do {                                                                          \
  42   size_t i;                                                                   \
  43   for (i = 0; i < NAME.n; ++i)                                                \
  44     (*NAME.fn[i]) ARGS;                                                       \
  45 } while (0)
  46
  47 /* Define a hook variable with NAME and PROTO, and a function called RUNNER
  48    which calls each function on the hook in turn, with ARGS.  */
  49
  50 #define DEFINE_HOOK_RUNNER(name, runner, proto, args) \
  51 DEFINE_HOOK (name, proto); void runner proto { RUN_HOOK (name, args); }
  52
  53
  54 #endif