glibc/include/set-hooks.h

72 lines
2.4 KiB
C

/* Macros for using symbol sets for running lists of functions.
Copyright (C) 1994-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _SET_HOOKS_H
#define _SET_HOOKS_H 1
#define __need_size_t
#include <stddef.h>
#include <sys/cdefs.h>
#include <libc-symbols.h>
#ifdef symbol_set_define
/* Define a hook variable called NAME. Functions put on this hook take
arguments described by PROTO. Use `text_set_element (NAME, FUNCTION)'
from include/libc-symbols.h to add a function to the hook. */
# define DEFINE_HOOK(NAME, PROTO) \
typedef void __##NAME##_hook_function_t PROTO; \
symbol_set_define (NAME)
# define DECLARE_HOOK(NAME, PROTO) \
typedef void __##NAME##_hook_function_t PROTO;\
symbol_set_declare (NAME)
/* Run all the functions hooked on the set called NAME.
Each function is called like this: `function ARGS'. */
# define RUN_HOOK(NAME, ARGS) \
do { \
void *const *ptr; \
for (ptr = (void *const *) symbol_set_first_element (NAME); \
! symbol_set_end_p (NAME, ptr); ++ptr) \
(*(__##NAME##_hook_function_t *) *ptr) ARGS; \
} while (0)
/* Define a hook variable with NAME and PROTO, and a function called RUNNER
which calls each function on the hook in turn, with ARGS. */
# define DEFINE_HOOK_RUNNER(name, runner, proto, args) \
DEFINE_HOOK (name, proto); \
extern void runner proto; void runner proto { RUN_HOOK (name, args); }
#else
/* The system does not provide necessary support for this. */
# define DEFINE_HOOK(NAME, PROTO)
# define DECLARE_HOOK(NAME, PROTO)
# define RUN_HOOK(NAME, ARGS)
# define DEFINE_HOOK_RUNNER(name, runner, proto, args)
#endif
#endif /* set-hooks.h */