diff options
Diffstat (limited to 'hurd')
| -rw-r--r-- | hurd/set-hooks.h | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/hurd/set-hooks.h b/hurd/set-hooks.h new file mode 100644 index 0000000000..7264f61c19 --- /dev/null +++ b/hurd/set-hooks.h @@ -0,0 +1,96 @@ +/* Macros for using symbol sets for running lists of functions. + Copyright (C) 1994-2023 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 + <https://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> + +#include "set-hooks-arch.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); } + +# ifdef SET_RELHOOK +/* This is similar to RUN_RELHOOK, but the hooks were registered with + * SET_RELHOOK so that a relative offset was computed by the linker + * rather than an absolute address by the dynamic linker. */ +# define RUN_RELHOOK(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 *f = \ + (void*) ((uintptr_t) ptr + (ptrdiff_t) *ptr); \ + (*f) ARGS; \ + } \ +} while (0) +# else +# define SET_RELHOOK(NAME, HOOK) text_set_element (NAME, HOOK) +# define RUN_RELHOOK(NAME, ARGS) RUN_HOOK(NAME, ARGS) +# endif + +#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) + +# define SET_RELHOOK(NAME, HOOK) + +# define RUN_RELHOOK(NAME, ARGS) + +#endif + +#endif /* set-hooks.h */ |