1 /* Copyright (C) 1991,92,93,95,96,97,98,99,2000,2001 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19 #ifndef _LIBC_INTERNAL_H
20 #define _LIBC_INTERNAL_H 1
25 /* GCC understands weak symbols and aliases; use its interface where
26 possible, instead of embedded assembly language. */
28 /* Define ALIASNAME as a strong alias for NAME. */
29 # define strong_alias(name, aliasname) _strong_alias(name, aliasname)
30 # define _strong_alias(name, aliasname) \
31 extern __typeof (name) aliasname __attribute__ ((alias (#name)));
33 /* This comes between the return type and function name in
34 a function definition to make that definition weak. */
35 # define weak_function __attribute__ ((weak))
36 # define weak_const_function __attribute__ ((weak, __const__))
38 /* Define ALIASNAME as a weak alias for NAME.
39 If weak aliases are not available, this defines a strong alias. */
40 # define weak_alias(name, aliasname) _weak_alias (name, aliasname)
41 # define _weak_alias(name, aliasname) \
42 extern __typeof (name) aliasname __attribute__ ((weak, alias (#name)));
44 /* Declare SYMBOL as weak undefined symbol (resolved to 0 if not defined). */
45 # define weak_extern(symbol) _weak_extern (weak symbol)
46 # define _weak_extern(expr) _Pragma (#expr)
48 #else /* __ASSEMBLER__ */
50 #ifdef __SYMBOL_PREFIX
51 # define C_SYMBOL_NAME(name) _##name
53 # define C_SYMBOL_NAME(name) name
56 # define strong_alias(name, aliasname) \
57 .global C_SYMBOL_NAME (aliasname) ; \
58 .set C_SYMBOL_NAME(aliasname),C_SYMBOL_NAME(name)
60 # define weak_alias(name, aliasname) \
61 .weak C_SYMBOL_NAME(aliasname) ; \
62 C_SYMBOL_NAME(aliasname) = C_SYMBOL_NAME(name)
64 # define weak_extern(symbol) \
65 .weak C_SYMBOL_NAME(symbol)
67 #endif /* __ASSEMBLER__ */
69 /* When a reference to SYMBOL is encountered, the linker will emit a
70 warning message MSG. */
73 /* We want the .gnu.warning.SYMBOL section to be unallocated. */
74 # define __make_section_unallocated(section_string) \
75 asm (".section " section_string "\n\t.previous");
77 /* Tacking on "\n\t#" to the section name makes gcc put it's bogus
78 section attributes on what looks like a comment to the assembler. */
79 # ifdef __sparc__ //HAVE_SECTION_QUOTES
80 # define __sec_comment "\"\n\t#\""
82 # define __sec_comment "\n\t#"
85 # define link_warning(symbol, msg)
87 # define link_warning(symbol, msg) \
88 __make_section_unallocated (".gnu.warning." #symbol) \
89 static const char __evoke_link_warning_##symbol[] \
90 __attribute__ ((used, section (".gnu.warning." #symbol __sec_comment))) \
93 #else /* __HAVE_ELF__ */
94 # define link_warning(symbol, msg) \
95 asm (".stabs \"" msg "\",30,0,0,0\n\t" \
96 ".stabs \"" __C_SYMBOL_PREFIX__ #symbol "\",1,0,0,0\n");
97 #endif /* __HAVE_ELF__ */
100 /* If we do not have the __attribute__ ((weak)) syntax, there is no way we
101 can define functions as weak symbols. The compiler will emit a `.globl'
102 directive for the function symbol, and a `.weak' directive in addition
103 will produce an error from the assembler. */
104 # define weak_function /* empty */
105 # define weak_const_function /* empty */
108 /* On some platforms we can make internal function calls (i.e., calls of
109 functions not exported) a bit faster by using a different calling
111 #if 0 /*def __i386__*/
112 # define internal_function __attribute__ ((regparm (3), stdcall))
114 #ifndef internal_function
115 # define internal_function /* empty */
119 # define IS_IN_libc 1
122 /* need this to unset defaults in libpthread for files that get added to libc */
127 /* Prepare for the case that `__builtin_expect' is not available. */
128 #if __GNUC__ == 2 && __GNUC_MINOR__ < 96
129 # define __builtin_expect(x, expected_value) (x)
132 # define likely(x) __builtin_expect((!!(x)),1)
135 # define unlikely(x) __builtin_expect((!!(x)),0)
137 #ifndef __LINUX_COMPILER_H
138 # define __LINUX_COMPILER_H
141 # define __cast__(_to)
144 #define attribute_unused __attribute__ ((unused))
146 /* The following macros are used for PLT bypassing within libc.so
147 (and if needed other libraries similarly).
148 First of all, you need to have the function prototyped somewhere,
153 If calls to foo within libc.so should always go to foo defined in libc.so,
154 then in include/foo.h you add:
156 libc_hidden_proto (foo)
158 line and after the foo function definition:
164 libc_hidden_def (foo)
172 libc_hidden_weak (foo)
174 Simularly for global data. If references to foo within libc.so should
175 always go to foo defined in libc.so, then in include/foo.h you add:
177 libc_hidden_proto (foo)
179 line and after foo's definition:
181 int foo = INITIAL_FOO_VALUE;
182 libc_hidden_data_def (foo)
186 int foo = INITIAL_FOO_VALUE;
187 libc_hidden_data_weak (foo)
189 If foo is normally just an alias (strong or weak) of some other function,
190 you should use the normal strong_alias first, then add libc_hidden_def
197 strong_alias (baz, foo)
198 libc_hidden_weak (foo)
200 If the function should be internal to multiple objects, say ld.so and
201 libc.so, the best way is to use:
203 #if !defined NOT_IN_libc || defined IS_IN_rtld
207 in include/foo.h and the normal macros at all function definitions
208 depending on what DSO they belong to.
210 If versioned_symbol macro is used to define foo,
211 libc_hidden_ver macro should be used, as in:
213 int __real_foo (int __bar)
217 versioned_symbol (libc, __real_foo, foo, GLIBC_2_1);
218 libc_hidden_ver (__real_foo, foo) */
220 /* uClibc specific (the above comment was copied from glibc):
221 * a. when ppc64 will be supported, we need changes to support:
222 * strong_data_alias (used by asm hidden_data_def) / HAVE_ASM_GLOBAL_DOT_NAME
223 * b. libc_hidden_proto(foo) should be added after the header having foo's prototype
224 * or after extern foo... to all source files that should use the internal version
225 * of foo within libc, even to the file defining foo itself, libc_hidden_def does
226 * not hide __GI_foo itself, although the name suggests it (hiding is done exclusively
227 * by libc_hidden_proto). The reasoning to have it after the header w/ foo's prototype is
228 * to get first the __REDIRECT from original header and then create the __GI_foo alias
229 * c. no versioning support, hidden[_data]_ver are noop */
231 /* Arrange to hide uClibc internals */
232 #if __GNUC_PREREQ (3, 3)
233 # define attribute_hidden __attribute__ ((visibility ("hidden")))
234 # define __hidden_proto_hiddenattr(attrs...) __attribute__ ((visibility ("hidden"), ##attrs))
236 # define attribute_hidden
237 # define __hidden_proto_hiddenattr(attrs...)
240 /* if ppc64 will be supported, this section needs adapting due to HAVE_ASM_GLOBAL_DOT_NAME */
242 # ifndef __ASSEMBLER__
243 # define hidden_strong_alias(name, aliasname) _hidden_strong_alias(name, aliasname)
244 # define _hidden_strong_alias(name, aliasname) \
245 extern __typeof (name) aliasname __attribute__ ((alias (#name))) attribute_hidden;
247 # define hidden_weak_alias(name, aliasname) _hidden_weak_alias (name, aliasname)
248 # define _hidden_weak_alias(name, aliasname) \
249 extern __typeof (name) aliasname __attribute__ ((weak, alias (#name))) attribute_hidden;
251 # define hidden_proto(name, attrs...) __hidden_proto (name, __GI_##name, ##attrs)
252 # define __hidden_proto(name, internal, attrs...) \
253 extern __typeof (name) name __asm__ (__hidden_asmname (#internal)) \
254 __hidden_proto_hiddenattr (attrs);
255 # define __hidden_asmname(name) __hidden_asmname1 (__USER_LABEL_PREFIX__, name)
256 # define __hidden_asmname1(prefix, name) __hidden_asmname2(prefix, name)
257 # define __hidden_asmname2(prefix, name) #prefix name
258 # define __hidden_ver1(local, internal, name) \
259 extern __typeof (name) __EI_##name __asm__(__hidden_asmname (#internal)); \
260 extern __typeof (name) __EI_##name __attribute__((alias (__hidden_asmname (#local))))
261 # define hidden_def(name) __hidden_ver1(__GI_##name, name, name);
262 # define hidden_data_def(name) hidden_def(name)
263 # define hidden_weak(name) __hidden_ver1(__GI_##name, name, name) __attribute__((weak));
264 # define hidden_data_weak(name) hidden_weak(name)
266 # else /* __ASSEMBLER__ */
267 # define hidden_strong_alias(name, aliasname) \
268 .global C_SYMBOL_NAME (aliasname) ; \
269 .hidden C_SYMBOL_NAME (aliasname) ; \
270 .set C_SYMBOL_NAME(aliasname),C_SYMBOL_NAME(name)
272 # define hidden_weak_alias(name, aliasname) \
273 .weak C_SYMBOL_NAME(aliasname) ; \
274 .hidden C_SYMBOL_NAME(aliasname) ; \
275 C_SYMBOL_NAME(aliasname) = C_SYMBOL_NAME(name)
277 /* For assembly, we need to do the opposite of what we do in C:
278 in assembly gcc __REDIRECT stuff is not in place, so functions
279 are defined by its normal name and we need to create the
280 __GI_* alias to it, in C __REDIRECT causes the function definition
281 to use __GI_* name and we need to add alias to the real name.
282 There is no reason to use hidden_weak over hidden_def in assembly,
283 but we provide it for consistency with the C usage.
284 hidden_proto doesn't make sense for assembly but the equivalent
285 is to call via the HIDDEN_JUMPTARGET macro instead of JUMPTARGET. */
286 # define hidden_def(name) hidden_strong_alias (name, __GI_##name)
287 # define hidden_data_def(name) hidden_strong_alias (name, __GI_##name)
288 # define hidden_weak(name) hidden_def (name)
289 # define hidden_data_weak(name) hidden_data_def (name)
290 # define HIDDEN_JUMPTARGET(name) __GI_##name
291 # endif /* __ASSEMBLER__ */
293 # define hidden_strong_alias(name, aliasname)
294 # define hidden_weak_alias(name, aliasname)
296 # ifndef __ASSEMBLER__
297 # define hidden_proto(name, attrs...)
299 # define HIDDEN_JUMPTARGET(name) name
301 # define hidden_def(name)
302 # define hidden_data_def(name)
303 # define hidden_weak(name)
304 # define hidden_data_weak(name)
307 /* uClibc does not support versioning yet. */
308 #define versioned_symbol(lib, local, symbol, version) /* weak_alias(local, symbol) */
309 #define hidden_ver(local, name) /* strong_alias(local, __GI_##name) */
310 #define hidden_data_ver(local, name) /* strong_alias(local,__GI_##name) */
312 #if !defined NOT_IN_libc
313 # define libc_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
314 # define libc_hidden_def(name) hidden_def (name)
315 # define libc_hidden_weak(name) hidden_weak (name)
316 # define libc_hidden_ver(local, name) hidden_ver (local, name)
317 # define libc_hidden_data_def(name) hidden_data_def (name)
318 # define libc_hidden_data_weak(name) hidden_data_weak (name)
319 # define libc_hidden_data_ver(local, name) hidden_data_ver (local, name)
321 # define libc_hidden_proto(name, attrs...)
322 # define libc_hidden_def(name)
323 # define libc_hidden_weak(name)
324 # define libc_hidden_ver(local, name)
325 # define libc_hidden_data_def(name)
326 # define libc_hidden_data_weak(name)
327 # define libc_hidden_data_ver(local, name)
330 #if defined NOT_IN_libc && defined IS_IN_rtld
331 # define rtld_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
332 # define rtld_hidden_def(name) hidden_def (name)
333 # define rtld_hidden_weak(name) hidden_weak (name)
334 # define rtld_hidden_ver(local, name) hidden_ver (local, name)
335 # define rtld_hidden_data_def(name) hidden_data_def (name)
336 # define rtld_hidden_data_weak(name) hidden_data_weak (name)
337 # define rtld_hidden_data_ver(local, name) hidden_data_ver (local, name)
339 # define rtld_hidden_proto(name, attrs...)
340 # define rtld_hidden_def(name)
341 # define rtld_hidden_weak(name)
342 # define rtld_hidden_ver(local, name)
343 # define rtld_hidden_data_def(name)
344 # define rtld_hidden_data_weak(name)
345 # define rtld_hidden_data_ver(local, name)
348 #if defined NOT_IN_libc && defined IS_IN_libm
349 # define libm_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
350 # define libm_hidden_def(name) hidden_def (name)
351 # define libm_hidden_weak(name) hidden_weak (name)
352 # define libm_hidden_ver(local, name) hidden_ver (local, name)
353 # define libm_hidden_data_def(name) hidden_data_def (name)
354 # define libm_hidden_data_weak(name) hidden_data_weak (name)
355 # define libm_hidden_data_ver(local, name) hidden_data_ver (local, name)
357 # define libm_hidden_proto(name, attrs...)
358 # define libm_hidden_def(name)
359 # define libm_hidden_weak(name)
360 # define libm_hidden_ver(local, name)
361 # define libm_hidden_data_def(name)
362 # define libm_hidden_data_weak(name)
363 # define libm_hidden_data_ver(local, name)
366 #if defined NOT_IN_libc && defined IS_IN_libresolv
367 # define libresolv_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
368 # define libresolv_hidden_def(name) hidden_def (name)
369 # define libresolv_hidden_weak(name) hidden_weak (name)
370 # define libresolv_hidden_ver(local, name) hidden_ver (local, name)
371 # define libresolv_hidden_data_def(name) hidden_data_def (name)
372 # define libresolv_hidden_data_weak(name) hidden_data_weak (name)
373 # define libresolv_hidden_data_ver(local, name) hidden_data_ver (local, name)
375 # define libresolv_hidden_proto(name, attrs...)
376 # define libresolv_hidden_def(name)
377 # define libresolv_hidden_weak(name)
378 # define libresolv_hidden_ver(local, name)
379 # define libresolv_hidden_data_def(name)
380 # define libresolv_hidden_data_weak(name)
381 # define libresolv_hidden_data_ver(local, name)
384 #if defined NOT_IN_libc && defined IS_IN_librt
385 # define librt_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
386 # define librt_hidden_def(name) hidden_def (name)
387 # define librt_hidden_weak(name) hidden_weak (name)
388 # define librt_hidden_ver(local, name) hidden_ver (local, name)
389 # define librt_hidden_data_def(name) hidden_data_def (name)
390 # define librt_hidden_data_weak(name) hidden_data_weak (name)
391 # define librt_hidden_data_ver(local, name) hidden_data_ver (local, name)
393 # define librt_hidden_proto(name, attrs...)
394 # define librt_hidden_def(name)
395 # define librt_hidden_weak(name)
396 # define librt_hidden_ver(local, name)
397 # define librt_hidden_data_def(name)
398 # define librt_hidden_data_weak(name)
399 # define librt_hidden_data_ver(local, name)
402 #if defined NOT_IN_libc && defined IS_IN_libdl
403 # define libdl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
404 # define libdl_hidden_def(name) hidden_def (name)
405 # define libdl_hidden_weak(name) hidden_weak (name)
406 # define libdl_hidden_ver(local, name) hidden_ver (local, name)
407 # define libdl_hidden_data_def(name) hidden_data_def (name)
408 # define libdl_hidden_data_weak(name) hidden_data_weak (name)
409 # define libdl_hidden_data_ver(local, name) hidden_data_ver (local, name)
411 # define libdl_hidden_proto(name, attrs...)
412 # define libdl_hidden_def(name)
413 # define libdl_hidden_weak(name)
414 # define libdl_hidden_ver(local, name)
415 # define libdl_hidden_data_def(name)
416 # define libdl_hidden_data_weak(name)
417 # define libdl_hidden_data_ver(local, name)
420 #if defined NOT_IN_libc && defined IS_IN_libintl
421 # define libintl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
422 # define libintl_hidden_def(name) hidden_def (name)
423 # define libintl_hidden_weak(name) hidden_weak (name)
424 # define libintl_hidden_ver(local, name) hidden_ver (local, name)
425 # define libintl_hidden_data_def(name) hidden_data_def (name)
426 # define libintl_hidden_data_weak(name) hidden_data_weak (name)
427 # define libintl_hidden_data_ver(local, name) hidden_data_ver(local, name)
429 # define libintl_hidden_proto(name, attrs...)
430 # define libintl_hidden_def(name)
431 # define libintl_hidden_weak(name)
432 # define libintl_hidden_ver(local, name)
433 # define libintl_hidden_data_def(name)
434 # define libintl_hidden_data_weak(name)
435 # define libintl_hidden_data_ver(local, name)
438 #if defined NOT_IN_libc && defined IS_IN_libnsl
439 # define libnsl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
440 # define libnsl_hidden_def(name) hidden_def (name)
441 # define libnsl_hidden_weak(name) hidden_weak (name)
442 # define libnsl_hidden_ver(local, name) hidden_ver (local, name)
443 # define libnsl_hidden_data_def(name) hidden_data_def (name)
444 # define libnsl_hidden_data_weak(name) hidden_data_weak (name)
445 # define libnsl_hidden_data_ver(local, name) hidden_data_ver (local, name)
447 # define libnsl_hidden_proto(name, attrs...)
448 # define libnsl_hidden_def(name)
449 # define libnsl_hidden_weak(name)
450 # define libnsl_hidden_ver(local, name)
451 # define libnsl_hidden_data_def(name)
452 # define libnsl_hidden_data_weak(name)
453 # define libnsl_hidden_data_ver(local, name)
456 #if defined NOT_IN_libc && defined IS_IN_libutil
457 # define libutil_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
458 # define libutil_hidden_def(name) hidden_def (name)
459 # define libutil_hidden_weak(name) hidden_weak (name)
460 # define libutil_hidden_ver(local, name) hidden_ver (local, name)
461 # define libutil_hidden_data_def(name) hidden_data_def (name)
462 # define libutil_hidden_data_weak(name) hidden_data_weak (name)
463 # define libutil_hidden_data_ver(local, name) hidden_data_ver (local, name)
465 # define libutil_hidden_proto(name, attrs...)
466 # define libutil_hidden_def(name)
467 # define libutil_hidden_weak(name)
468 # define libutil_hidden_ver(local, name)
469 # define libutil_hidden_data_def(name)
470 # define libutil_hidden_data_weak(name)
471 # define libutil_hidden_data_ver(local, name)
474 #if defined NOT_IN_libc && defined IS_IN_libcrypt
475 # define libcrypt_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
476 # define libcrypt_hidden_def(name) hidden_def (name)
477 # define libcrypt_hidden_weak(name) hidden_weak (name)
478 # define libcrypt_hidden_ver(local, name) hidden_ver (local, name)
479 # define libcrypt_hidden_data_def(name) hidden_data_def (name)
480 # define libcrypt_hidden_data_weak(name) hidden_data_weak (name)
481 # define libcrypt_hidden_data_ver(local, name) hidden_data_ver (local, name)
483 # define libcrypt_hidden_proto(name, attrs...)
484 # define libcrypt_hidden_def(name)
485 # define libcrypt_hidden_weak(name)
486 # define libcrypt_hidden_ver(local, name)
487 # define libcrypt_hidden_data_def(name)
488 # define libcrypt_hidden_data_weak(name)
489 # define libcrypt_hidden_data_ver(local, name)
492 #if defined NOT_IN_libc && defined IS_IN_libpthread
493 # define libpthread_hidden_proto(name, attrs...) hidden_proto (name, ##attrs)
494 # define libpthread_hidden_def(name) hidden_def (name)
495 # define libpthread_hidden_weak(name) hidden_weak (name)
496 # define libpthread_hidden_ver(local, name) hidden_ver (local, name)
497 # define libpthread_hidden_data_def(name) hidden_data_def (name)
498 # define libpthread_hidden_data_weak(name) hidden_data_weak (name)
499 # define libpthread_hidden_data_ver(local, name) hidden_data_ver (local, name)
501 # define libpthread_hidden_proto(name, attrs...)
502 # define libpthread_hidden_def(name)
503 # define libpthread_hidden_weak(name)
504 # define libpthread_hidden_ver(local, name)
505 # define libpthread_hidden_data_def(name)
506 # define libpthread_hidden_data_weak(name)
507 # define libpthread_hidden_data_ver(local, name)
510 #ifdef __UCLIBC_BUILD_RELRO__
511 # define attribute_relro __attribute__ ((section (".data.rel.ro")))
513 # define attribute_relro
517 # define attribute_noreturn __attribute__ ((__noreturn__))
519 # define attribute_noreturn
522 #ifdef __UCLIBC_HAS_THREADS_NATIVE__
523 # define attribute_tls_model_ie __attribute__ ((tls_model ("initial-exec")))
526 /* Pull in things like __attribute_used__ */
527 #include <sys/cdefs.h>
529 /* --- this is added to integrate linuxthreads */
530 #define __USE_UNIX98 1
532 #ifndef __ASSEMBLER__
535 # define __need_size_t
538 /* sources are built w/ _GNU_SOURCE, this gets undefined */
539 extern int __xpg_strerror_r (int __errnum, char *__buf, size_t __buflen);
540 //extern char *__glibc_strerror_r (int __errnum, char *__buf, size_t __buflen);
542 /* #include <pthread.h> */
543 # ifndef __UCLIBC_HAS_THREADS__
544 # define __pthread_mutex_init(mutex, mutexattr) ((void)0)
545 # define __pthread_mutex_lock(mutex) ((void)0)
546 # define __pthread_mutex_trylock(mutex) ((void)0)
547 # define __pthread_mutex_unlock(mutex) ((void)0)
550 /* internal access to program name */
551 extern const char *__uclibc_progname attribute_hidden;
553 # endif /* IS_IN_libc */
555 /* #include <alloca.h> */
556 #include <bits/stackinfo.h>
557 #if _STACK_GROWS_DOWN
558 # define extend_alloca(buf, len, newlen) \
559 (__typeof (buf)) ({ size_t __newlen = (newlen); \
560 char *__newbuf = alloca (__newlen); \
561 if (__newbuf + __newlen == (char *) buf) \
566 #elif _STACK_GROWS_UP
567 # define extend_alloca(buf, len, newlen) \
568 (__typeof (buf)) ({ size_t __newlen = (newlen); \
569 char *__newbuf = alloca (__newlen); \
570 char *__buf = (buf); \
571 if (__buf + __newlen == __newbuf) \
580 # warning unknown stack
581 # define extend_alloca(buf, len, newlen) \
582 alloca (((len) = (newlen)))
585 #endif /* __ASSEMBLER__ */
587 #endif /* _LIBC_INTERNAL_H */