diff options
Diffstat (limited to 'include/libc-symbols.h')
| -rw-r--r-- | include/libc-symbols.h | 969 |
1 files changed, 0 insertions, 969 deletions
diff --git a/include/libc-symbols.h b/include/libc-symbols.h deleted file mode 100644 index 3310e3a678..0000000000 --- a/include/libc-symbols.h +++ /dev/null @@ -1,969 +0,0 @@ -/* Support macros for making weak and strong aliases for symbols, - and for using symbol sets and linker warnings with GNU ld. - Copyright (C) 1995-2017 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 _LIBC_SYMBOLS_H -#define _LIBC_SYMBOLS_H 1 - -/* This file is included implicitly in the compilation of every source file, - using -include. It includes config.h. */ - -/* Enable declarations of GNU extensions, since we are compiling them. */ -#define _GNU_SOURCE 1 - -#ifdef MODULE_NAME - -/* Use `#if IS_IN (module)` to detect what component is being compiled. */ -#define PASTE_NAME1(a,b) a##b -#define PASTE_NAME(a,b) PASTE_NAME1 (a,b) -#define IN_MODULE PASTE_NAME (MODULE_, MODULE_NAME) -#define IS_IN(lib) (IN_MODULE == MODULE_##lib) - -/* True if the current module is a versioned library. Versioned - library names culled from shlib-versions files are assigned a - MODULE_* value greater than MODULE_LIBS_BEGIN. */ -#define IS_IN_LIB (IN_MODULE > MODULE_LIBS_BEGIN) - -/* The testsuite, and some other ancillary code, should be compiled against - as close an approximation to the installed headers as possible. - Defining this symbol disables most internal-use-only declarations - provided by this header, and all those provided by other internal - wrapper headers. */ -#if IS_IN (testsuite) || defined IS_IN_build || defined __cplusplus -# define _ISOMAC 1 -#endif - -#else -/* The generation process for a few files created very early in the - build (notably libc-modules.h itself) involves preprocessing this - header without defining MODULE_NAME. Under these conditions, - internal declarations (especially from config.h) must be visible, - but IS_IN should always evaluate as false. */ -# define IS_IN(lib) 0 -# define IS_IN_LIB 0 -# define IN_MODULE (-1) -#endif - -#ifndef _ISOMAC - -/* This is defined for the compilation of all C library code. features.h - tests this to avoid inclusion of stubs.h while compiling the library, - before stubs.h has been generated. Some library code that is shared - with other packages also tests this symbol to see if it is being - compiled as part of the C library. We must define this before including - config.h, because it makes some definitions conditional on whether libc - itself is being compiled, or just some generator program. */ -#define _LIBC 1 - -/* Some files must be compiled with optimization on. */ -#if !defined __ASSEMBLER__ && !defined __OPTIMIZE__ -# error "glibc cannot be compiled without optimization" -#endif - -/* -ffast-math cannot be applied to the C library, as it alters the ABI. - Some test components that use -ffast-math are currently not part of - IS_IN (testsuite) for technical reasons, so we have a secondary override. */ -#if defined __FAST_MATH__ && !defined TEST_FAST_MATH -# error "glibc must not be compiled with -ffast-math" -#endif - -#include <config.h> - -/* Define this for the benefit of portable GNU code that wants to check it. - Code that checks with #if will not #include <config.h> again, since we've - already done it (and this file is implicitly included in every compile, - via -include). Code that checks with #ifdef will #include <config.h>, - but that file should always be idempotent (i.e., it's just #define/#undef - and nothing else anywhere should be changing the macro state it touches), - so it's harmless. */ -#define HAVE_CONFIG_H 0 - -/* Define these macros for the benefit of portable GNU code that wants to check - them. Of course, STDC_HEADERS is never false when building libc! */ -#define STDC_HEADERS 1 -#define HAVE_MBSTATE_T 1 -#define HAVE_MBSRTOWCS 1 -#define HAVE_LIBINTL_H 1 -#define HAVE_WCTYPE_H 1 -#define HAVE_ISWCTYPE 1 -#define ENABLE_NLS 1 - -/* The symbols in all the user (non-_) macros are C symbols. */ - -#ifndef __SYMBOL_PREFIX -# define __SYMBOL_PREFIX -#endif - -#ifndef C_SYMBOL_NAME -# define C_SYMBOL_NAME(name) name -#endif - -#ifndef ASM_LINE_SEP -# define ASM_LINE_SEP ; -#endif - -#ifndef __ASSEMBLER__ -/* GCC understands weak symbols and aliases; use its interface where - possible, instead of embedded assembly language. */ - -/* Define ALIASNAME as a strong alias for NAME. */ -# define strong_alias(name, aliasname) _strong_alias(name, aliasname) -# define _strong_alias(name, aliasname) \ - extern __typeof (name) aliasname __attribute__ ((alias (#name))); - -/* This comes between the return type and function name in - a function definition to make that definition weak. */ -# define weak_function __attribute__ ((weak)) -# define weak_const_function __attribute__ ((weak, __const__)) - -/* Define ALIASNAME as a weak alias for NAME. - If weak aliases are not available, this defines a strong alias. */ -# define weak_alias(name, aliasname) _weak_alias (name, aliasname) -# define _weak_alias(name, aliasname) \ - extern __typeof (name) aliasname __attribute__ ((weak, alias (#name))); - -/* Same as WEAK_ALIAS, but mark symbol as hidden. */ -# define weak_hidden_alias(name, aliasname) \ - _weak_hidden_alias (name, aliasname) -# define _weak_hidden_alias(name, aliasname) \ - extern __typeof (name) aliasname \ - __attribute__ ((weak, alias (#name), __visibility__ ("hidden"))); - -/* Declare SYMBOL as weak undefined symbol (resolved to 0 if not defined). */ -# define weak_extern(symbol) _weak_extern (weak symbol) -# define _weak_extern(expr) _Pragma (#expr) - -/* In shared builds, the expression call_function_static_weak - (FUNCTION-SYMBOL, ARGUMENTS) invokes FUNCTION-SYMBOL (an - identifier) unconditionally, with the (potentially empty) argument - list ARGUMENTS. In static builds, if FUNCTION-SYMBOL has a - definition, the function is invoked as before; if FUNCTION-SYMBOL - is NULL, no call is performed. */ -# ifdef SHARED -# define call_function_static_weak(func, ...) func (__VA_ARGS__) -# else /* !SHARED */ -# define call_function_static_weak(func, ...) \ - ({ \ - extern __typeof__ (func) func weak_function; \ - (func != NULL ? func (__VA_ARGS__) : (void)0); \ - }) -# endif - -#else /* __ASSEMBLER__ */ - -# ifdef HAVE_ASM_SET_DIRECTIVE -# define strong_alias(original, alias) \ - .globl C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original) -# define strong_data_alias(original, alias) strong_alias(original, alias) -# else -# define strong_alias(original, alias) \ - .globl C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) -# define strong_data_alias(original, alias) strong_alias(original, alias) -# endif - -# define weak_alias(original, alias) \ - .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) - -# define weak_extern(symbol) \ - .weak C_SYMBOL_NAME (symbol) - -#endif /* __ASSEMBLER__ */ - -/* On some platforms we can make internal function calls (i.e., calls of - functions not exported) a bit faster by using a different calling - convention. */ -#ifndef internal_function -# define internal_function /* empty */ -#endif - -/* Determine the return address. */ -#define RETURN_ADDRESS(nr) \ - __builtin_extract_return_addr (__builtin_return_address (nr)) - -/* When a reference to SYMBOL is encountered, the linker will emit a - warning message MSG. */ -/* We want the .gnu.warning.SYMBOL section to be unallocated. */ -#define __make_section_unallocated(section_string) \ - asm (".section " section_string "\n\t.previous"); - -/* Tacking on "\n\t#" to the section name makes gcc put it's bogus - section attributes on what looks like a comment to the assembler. */ -#ifdef HAVE_SECTION_QUOTES -# define __sec_comment "\"\n\t#\"" -#else -# define __sec_comment "\n\t#" -#endif -#define link_warning(symbol, msg) \ - __make_section_unallocated (".gnu.warning." #symbol) \ - static const char __evoke_link_warning_##symbol[] \ - __attribute__ ((used, section (".gnu.warning." #symbol __sec_comment))) \ - = msg; -#define libc_freeres_ptr(decl) \ - __make_section_unallocated ("__libc_freeres_ptrs, \"aw\", %nobits") \ - decl __attribute__ ((section ("__libc_freeres_ptrs" __sec_comment))) -#define __libc_freeres_fn_section \ - __attribute__ ((section ("__libc_freeres_fn"))) - -#define libc_freeres_fn(name) \ - static void name (void) __attribute_used__ __libc_freeres_fn_section; \ - text_set_element (__libc_subfreeres, name); \ - static void name (void) - -/* A canned warning for sysdeps/stub functions. */ -#define stub_warning(name) \ - __make_section_unallocated (".gnu.glibc-stub." #name) \ - link_warning (name, #name " is not implemented and will always fail") - -/* Warning for linking functions calling dlopen into static binaries. */ -#ifdef SHARED -#define static_link_warning(name) -#else -#define static_link_warning(name) static_link_warning1(name) -#define static_link_warning1(name) \ - link_warning(name, "Using '" #name "' in statically linked applications \ -requires at runtime the shared libraries from the glibc version used \ -for linking") -#endif - -/* Declare SYMBOL to be TYPE (`function' or `object') of SIZE bytes - alias to ORIGINAL, when the assembler supports such declarations - (such as in ELF). - This is only necessary when defining something in assembly, or playing - funny alias games where the size should be other than what the compiler - thinks it is. */ -#define declare_symbol_alias(symbol, original, type, size) \ - declare_symbol_alias_1 (symbol, original, type, size) -#ifdef __ASSEMBLER__ -# define declare_symbol_alias_1(symbol, original, type, size) \ - strong_alias (original, symbol); \ - .type C_SYMBOL_NAME (symbol), %##type; \ - .size C_SYMBOL_NAME (symbol), size -#else /* Not __ASSEMBLER__. */ -# define declare_symbol_alias_1(symbol, original, type, size) \ - asm (".globl " __SYMBOL_PREFIX #symbol \ - "\n\t" declare_symbol_alias_1_alias (symbol, original) \ - "\n\t.type " __SYMBOL_PREFIX #symbol ", " \ - "%" #type \ - "\n\t.size " __SYMBOL_PREFIX #symbol ", " #size); -# ifdef HAVE_ASM_SET_DIRECTIVE -# define declare_symbol_alias_1_alias(symbol, original) \ - ".set " __SYMBOL_PREFIX #symbol ", " __SYMBOL_PREFIX #original -# else -# define declare_symbol_alias_1_alias(symbol, original) \ - __SYMBOL_PREFIX #symbol " = " __SYMBOL_PREFIX #original -# endif /* HAVE_ASM_SET_DIRECTIVE */ -#endif /* __ASSEMBLER__ */ - - -/* - -*/ - -/* Symbol set support macros. */ - -/* Make SYMBOL, which is in the text segment, an element of SET. */ -#define text_set_element(set, symbol) _elf_set_element(set, symbol) -/* Make SYMBOL, which is in the data segment, an element of SET. */ -#define data_set_element(set, symbol) _elf_set_element(set, symbol) -/* Make SYMBOL, which is in the bss segment, an element of SET. */ -#define bss_set_element(set, symbol) _elf_set_element(set, symbol) - -/* These are all done the same way in ELF. - There is a new section created for each set. */ -#ifdef SHARED -/* When building a shared library, make the set section writable, - because it will need to be relocated at run time anyway. */ -# define _elf_set_element(set, symbol) \ - static const void *__elf_set_##set##_element_##symbol##__ \ - __attribute__ ((used, section (#set))) = &(symbol) -#else -# define _elf_set_element(set, symbol) \ - static const void *const __elf_set_##set##_element_##symbol##__ \ - __attribute__ ((used, section (#set))) = &(symbol) -#endif - -/* Define SET as a symbol set. This may be required (it is in a.out) to - be able to use the set's contents. */ -#define symbol_set_define(set) symbol_set_declare(set) - -/* Declare SET for use in this module, if defined in another module. - In a shared library, this is always local to that shared object. - For static linking, the set might be wholly absent and so we use - weak references. */ -#define symbol_set_declare(set) \ - extern char const __start_##set[] __symbol_set_attribute; \ - extern char const __stop_##set[] __symbol_set_attribute; -#ifdef SHARED -# define __symbol_set_attribute attribute_hidden -#else -# define __symbol_set_attribute __attribute__ ((weak)) -#endif - -/* Return a pointer (void *const *) to the first element of SET. */ -#define symbol_set_first_element(set) ((void *const *) (&__start_##set)) - -/* Return true iff PTR (a void *const *) has been incremented - past the last element in SET. */ -#define symbol_set_end_p(set, ptr) ((ptr) >= (void *const *) &__stop_##set) - -/* Use symbol_version_reference to specify the version a symbol - reference should link to. Use symbol_version or - default_symbol_version for the definition of a versioned symbol. - The difference is that the latter is a no-op in non-shared - builds. */ -#ifdef __ASSEMBLER__ -# define symbol_version_reference(real, name, version) \ - .symver real, name##@##version -#else /* !__ASSEMBLER__ */ -# define symbol_version_reference(real, name, version) \ - __asm__ (".symver " #real "," #name "@" #version) -#endif - -#ifdef SHARED -# define symbol_version(real, name, version) \ - symbol_version_reference(real, name, version) -# define default_symbol_version(real, name, version) \ - _default_symbol_version(real, name, version) -# ifdef __ASSEMBLER__ -# define _default_symbol_version(real, name, version) \ - .symver real, name##@##@##version -# else -# define _default_symbol_version(real, name, version) \ - __asm__ (".symver " #real "," #name "@@" #version) -# endif -#else -# define symbol_version(real, name, version) -# define default_symbol_version(real, name, version) \ - strong_alias(real, name) -#endif - -#if defined SHARED || defined LIBC_NONSHARED -# define attribute_hidden __attribute__ ((visibility ("hidden"))) -#else -# define attribute_hidden -#endif - -#define attribute_tls_model_ie __attribute__ ((tls_model ("initial-exec"))) - -#define attribute_relro __attribute__ ((section (".data.rel.ro"))) - - -/* Used to disable stack protection in sensitive places, like ifunc - resolvers and early static TLS init. */ -#ifdef HAVE_CC_NO_STACK_PROTECTOR -# define inhibit_stack_protector \ - __attribute__ ((__optimize__ ("-fno-stack-protector"))) -#else -# define inhibit_stack_protector -#endif - -/* The following macros are used for PLT bypassing within libc.so - (and if needed other libraries similarly). - First of all, you need to have the function prototyped somewhere, - say in foo/foo.h: - - int foo (int __bar); - - If calls to foo within libc.so should always go to foo defined in libc.so, - then in include/foo.h you add: - - libc_hidden_proto (foo) - - line and after the foo function definition: - - int foo (int __bar) - { - return __bar; - } - libc_hidden_def (foo) - - or - - int foo (int __bar) - { - return __bar; - } - libc_hidden_weak (foo) - - Similarly for global data. If references to foo within libc.so should - always go to foo defined in libc.so, then in include/foo.h you add: - - libc_hidden_proto (foo) - - line and after foo's definition: - - int foo = INITIAL_FOO_VALUE; - libc_hidden_data_def (foo) - - or - - int foo = INITIAL_FOO_VALUE; - libc_hidden_data_weak (foo) - - If foo is normally just an alias (strong or weak) to some other function, - you should use the normal strong_alias first, then add libc_hidden_def - or libc_hidden_weak: - - int baz (int __bar) - { - return __bar; - } - strong_alias (baz, foo) - libc_hidden_weak (foo) - - If the function should be internal to multiple objects, say ld.so and - libc.so, the best way is to use: - - #if IS_IN (libc) || IS_IN (rtld) - hidden_proto (foo) - #endif - - in include/foo.h and the normal macros at all function definitions - depending on what DSO they belong to. - - If versioned_symbol macro is used to define foo, - libc_hidden_ver macro should be used, as in: - - int __real_foo (int __bar) - { - return __bar; - } - versioned_symbol (libc, __real_foo, foo, GLIBC_2_1); - libc_hidden_ver (__real_foo, foo) */ - -#if defined SHARED && !defined NO_HIDDEN -# ifndef __ASSEMBLER__ -# define __hidden_proto_hiddenattr(attrs...) \ - __attribute__ ((visibility ("hidden"), ##attrs)) -# define hidden_proto(name, attrs...) \ - __hidden_proto (name, , __GI_##name, ##attrs) -# define hidden_tls_proto(name, attrs...) \ - __hidden_proto (name, __thread, __GI_##name, ##attrs) -# define __hidden_proto(name, thread, internal, attrs...) \ - extern thread __typeof (name) name __asm__ (__hidden_asmname (#internal)) \ - __hidden_proto_hiddenattr (attrs); -# define __hidden_asmname(name) \ - __hidden_asmname1 (__USER_LABEL_PREFIX__, name) -# define __hidden_asmname1(prefix, name) __hidden_asmname2(prefix, name) -# define __hidden_asmname2(prefix, name) #prefix name -# define __hidden_ver1(local, internal, name) \ - extern __typeof (name) __EI_##name __asm__(__hidden_asmname (#internal)); \ - extern __typeof (name) __EI_##name \ - __attribute__((alias (__hidden_asmname (#local)))) -# define hidden_ver(local, name) __hidden_ver1(local, __GI_##name, name); -# define hidden_data_ver(local, name) hidden_ver(local, name) -# define hidden_def(name) __hidden_ver1(__GI_##name, name, name); -# define hidden_data_def(name) hidden_def(name) -# define hidden_weak(name) \ - __hidden_ver1(__GI_##name, name, name) __attribute__((weak)); -# define hidden_data_weak(name) hidden_weak(name) -# define hidden_nolink(name, lib, version) \ - __hidden_nolink1 (__GI_##name, __EI_##name, name, VERSION_##lib##_##version) -# define __hidden_nolink1(local, internal, name, version) \ - __hidden_nolink2 (local, internal, name, version) -# define __hidden_nolink2(local, internal, name, version) \ - extern __typeof (name) internal __attribute__ ((alias (#local))); \ - __hidden_nolink3 (local, internal, #name "@" #version) -# define __hidden_nolink3(local, internal, vername) \ - __asm__ (".symver " #internal ", " vername); -# else -/* For assembly, we need to do the opposite of what we do in C: - in assembly gcc __REDIRECT stuff is not in place, so functions - are defined by its normal name and we need to create the - __GI_* alias to it, in C __REDIRECT causes the function definition - to use __GI_* name and we need to add alias to the real name. - There is no reason to use hidden_weak over hidden_def in assembly, - but we provide it for consistency with the C usage. - hidden_proto doesn't make sense for assembly but the equivalent - is to call via the HIDDEN_JUMPTARGET macro instead of JUMPTARGET. */ -# define hidden_def(name) strong_alias (name, __GI_##name) -# define hidden_weak(name) hidden_def (name) -# define hidden_ver(local, name) strong_alias (local, __GI_##name) -# define hidden_data_def(name) strong_data_alias (name, __GI_##name) -# define hidden_data_weak(name) hidden_data_def (name) -# define hidden_data_ver(local, name) strong_data_alias (local, __GI_##name) -# define HIDDEN_JUMPTARGET(name) __GI_##name -# endif -#else -# ifndef __ASSEMBLER__ -# define hidden_proto(name, attrs...) -# define hidden_tls_proto(name, attrs...) -# else -# define HIDDEN_JUMPTARGET(name) JUMPTARGET(name) -# endif /* Not __ASSEMBLER__ */ -# define hidden_weak(name) -# define hidden_def(name) -# define hidden_ver(local, name) -# define hidden_data_weak(name) -# define hidden_data_def(name) -# define hidden_data_ver(local, name) -# define hidden_nolink(name, lib, version) -#endif - -#if IS_IN (libc) -# define libc_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define libc_hidden_tls_proto(name, attrs...) hidden_tls_proto (name, ##attrs) -# define libc_hidden_def(name) hidden_def (name) -# define libc_hidden_weak(name) hidden_weak (name) -# ifdef LINK_OBSOLETE_RPC - /* libc_hidden_nolink_sunrpc should only get used in sunrpc code. */ -# define libc_hidden_nolink_sunrpc(name, version) hidden_def (name) -# else -# define libc_hidden_nolink_sunrpc(name, version) hidden_nolink (name, libc, version) -# endif -# define libc_hidden_ver(local, name) hidden_ver (local, name) -# define libc_hidden_data_def(name) hidden_data_def (name) -# define libc_hidden_data_weak(name) hidden_data_weak (name) -# define libc_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define libc_hidden_proto(name, attrs...) -# define libc_hidden_tls_proto(name, attrs...) -# define libc_hidden_def(name) -# define libc_hidden_weak(name) -# define libc_hidden_ver(local, name) -# define libc_hidden_data_def(name) -# define libc_hidden_data_weak(name) -# define libc_hidden_data_ver(local, name) -#endif - -#if IS_IN (rtld) -# define rtld_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define rtld_hidden_tls_proto(name, attrs...) hidden_tls_proto (name, ##attrs) -# define rtld_hidden_def(name) hidden_def (name) -# define rtld_hidden_weak(name) hidden_weak (name) -# define rtld_hidden_ver(local, name) hidden_ver (local, name) -# define rtld_hidden_data_def(name) hidden_data_def (name) -# define rtld_hidden_data_weak(name) hidden_data_weak (name) -# define rtld_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define rtld_hidden_proto(name, attrs...) -# define rtld_hidden_tls_proto(name, attrs...) -# define rtld_hidden_def(name) -# define rtld_hidden_weak(name) -# define rtld_hidden_ver(local, name) -# define rtld_hidden_data_def(name) -# define rtld_hidden_data_weak(name) -# define rtld_hidden_data_ver(local, name) -#endif - -#if IS_IN (libm) -# define libm_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define libm_hidden_tls_proto(name, attrs...) hidden_tls_proto (name, ##attrs) -# define libm_hidden_def(name) hidden_def (name) -# define libm_hidden_weak(name) hidden_weak (name) -# define libm_hidden_ver(local, name) hidden_ver (local, name) -# define libm_hidden_data_def(name) hidden_data_def (name) -# define libm_hidden_data_weak(name) hidden_data_weak (name) -# define libm_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define libm_hidden_proto(name, attrs...) -# define libm_hidden_tls_proto(name, attrs...) -# define libm_hidden_def(name) -# define libm_hidden_weak(name) -# define libm_hidden_ver(local, name) -# define libm_hidden_data_def(name) -# define libm_hidden_data_weak(name) -# define libm_hidden_data_ver(local, name) -#endif - -#if IS_IN (libmvec) -# define libmvec_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define libmvec_hidden_tls_proto(name, attrs...) hidden_tls_proto (name, ##attrs) -# define libmvec_hidden_def(name) hidden_def (name) -# define libmvec_hidden_weak(name) hidden_weak (name) -# define libmvec_hidden_ver(local, name) hidden_ver (local, name) -# define libmvec_hidden_data_def(name) hidden_data_def (name) -# define libmvec_hidden_data_weak(name) hidden_data_weak (name) -# define libmvec_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define libmvec_hidden_proto(name, attrs...) -# define libmvec_hidden_tls_proto(name, attrs...) -# define libmvec_hidden_def(name) -# define libmvec_hidden_weak(name) -# define libmvec_hidden_ver(local, name) -# define libmvec_hidden_data_def(name) -# define libmvec_hidden_data_weak(name) -# define libmvec_hidden_data_ver(local, name) -#endif - -#if IS_IN (libresolv) -# define libresolv_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define libresolv_hidden_tls_proto(name, attrs...) \ - hidden_tls_proto (name, ##attrs) -# define libresolv_hidden_def(name) hidden_def (name) -# define libresolv_hidden_weak(name) hidden_weak (name) -# define libresolv_hidden_ver(local, name) hidden_ver (local, name) -# define libresolv_hidden_data_def(name) hidden_data_def (name) -# define libresolv_hidden_data_weak(name) hidden_data_weak (name) -# define libresolv_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define libresolv_hidden_proto(name, attrs...) -# define libresolv_hidden_tls_proto(name, attrs...) -# define libresolv_hidden_def(name) -# define libresolv_hidden_weak(name) -# define libresolv_hidden_ver(local, name) -# define libresolv_hidden_data_def(name) -# define libresolv_hidden_data_weak(name) -# define libresolv_hidden_data_ver(local, name) -#endif - -#if IS_IN (librt) -# define librt_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define librt_hidden_tls_proto(name, attrs...) \ - hidden_tls_proto (name, ##attrs) -# define librt_hidden_def(name) hidden_def (name) -# define librt_hidden_weak(name) hidden_weak (name) -# define librt_hidden_ver(local, name) hidden_ver (local, name) -# define librt_hidden_data_def(name) hidden_data_def (name) -# define librt_hidden_data_weak(name) hidden_data_weak (name) -# define librt_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define librt_hidden_proto(name, attrs...) -# define librt_hidden_tls_proto(name, attrs...) -# define librt_hidden_def(name) -# define librt_hidden_weak(name) -# define librt_hidden_ver(local, name) -# define librt_hidden_data_def(name) -# define librt_hidden_data_weak(name) -# define librt_hidden_data_ver(local, name) -#endif - -#if IS_IN (libdl) -# define libdl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define libdl_hidden_tls_proto(name, attrs...) \ - hidden_tls_proto (name, ##attrs) -# define libdl_hidden_def(name) hidden_def (name) -# define libdl_hidden_weak(name) hidden_weak (name) -# define libdl_hidden_ver(local, name) hidden_ver (local, name) -# define libdl_hidden_data_def(name) hidden_data_def (name) -# define libdl_hidden_data_weak(name) hidden_data_weak (name) -# define libdl_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define libdl_hidden_proto(name, attrs...) -# define libdl_hidden_tls_proto(name, attrs...) -# define libdl_hidden_def(name) -# define libdl_hidden_weak(name) -# define libdl_hidden_ver(local, name) -# define libdl_hidden_data_def(name) -# define libdl_hidden_data_weak(name) -# define libdl_hidden_data_ver(local, name) -#endif - -#if IS_IN (libnss_files) -# define libnss_files_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define libnss_files_hidden_tls_proto(name, attrs...) \ - hidden_tls_proto (name, ##attrs) -# define libnss_files_hidden_def(name) hidden_def (name) -# define libnss_files_hidden_weak(name) hidden_weak (name) -# define libnss_files_hidden_ver(local, name) hidden_ver (local, name) -# define libnss_files_hidden_data_def(name) hidden_data_def (name) -# define libnss_files_hidden_data_weak(name) hidden_data_weak (name) -# define libnss_files_hidden_data_ver(local, name) hidden_data_ver(local, name) -#else -# define libnss_files_hidden_proto(name, attrs...) -# define libnss_files_hidden_tls_proto(name, attrs...) -# define libnss_files_hidden_def(name) -# define libnss_files_hidden_weak(name) -# define libnss_files_hidden_ver(local, name) -# define libnss_files_hidden_data_def(name) -# define libnss_files_hidden_data_weak(name) -# define libnss_files_hidden_data_ver(local, name) -#endif - -#if IS_IN (libnsl) -# define libnsl_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define libnsl_hidden_tls_proto(name, attrs...) \ - hidden_tls_proto (name, ##attrs) -# ifdef LINK_OBSOLETE_NSL - /* libnsl_hidden_nolink should only get used in libnsl code. */ -# define libnsl_hidden_nolink_def(name, version) libnsl_hidden_def (name) -# else -# define libnsl_hidden_nolink_def(name, version) hidden_nolink (name, libnsl, version) -# endif -# define libnsl_hidden_def(name) hidden_def (name) -# define libnsl_hidden_weak(name) hidden_weak (name) -# define libnsl_hidden_ver(local, name) hidden_ver (local, name) -# define libnsl_hidden_data_def(name) hidden_data_def (name) -# define libnsl_hidden_data_weak(name) hidden_data_weak (name) -# define libnsl_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define libnsl_hidden_proto(name, attrs...) -# define libnsl_hidden_tls_proto(name, attrs...) -# define libnsl_hidden_def(name) -# define libnsl_hidden_weak(name) -# define libnsl_hidden_ver(local, name) -# define libnsl_hidden_data_def(name) -# define libnsl_hidden_data_weak(name) -# define libnsl_hidden_data_ver(local, name) -#endif - -#if IS_IN (libnss_nisplus) -# define libnss_nisplus_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define libnss_nisplus_hidden_tls_proto(name, attrs...) \ - hidden_tls_proto (name, ##attrs) -# define libnss_nisplus_hidden_def(name) hidden_def (name) -# define libnss_nisplus_hidden_weak(name) hidden_weak (name) -# define libnss_nisplus_hidden_ver(local, name) hidden_ver (local, name) -# define libnss_nisplus_hidden_data_def(name) hidden_data_def (name) -# define libnss_nisplus_hidden_data_weak(name) hidden_data_weak (name) -# define libnss_nisplus_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define libnss_nisplus_hidden_proto(name, attrs...) -# define libnss_nisplus_hidden_tls_proto(name, attrs...) -# define libnss_nisplus_hidden_def(name) -# define libnss_nisplus_hidden_weak(name) -# define libnss_nisplus_hidden_ver(local, name) -# define libnss_nisplus_hidden_data_def(name) -# define libnss_nisplus_hidden_data_weak(name) -# define libnss_nisplus_hidden_data_ver(local, name) -#endif - -#define libc_hidden_builtin_proto(name, attrs...) libc_hidden_proto (name, ##attrs) -#define libc_hidden_builtin_def(name) libc_hidden_def (name) -#define libc_hidden_builtin_weak(name) libc_hidden_weak (name) -#define libc_hidden_builtin_ver(local, name) libc_hidden_ver (local, name) -#ifdef __ASSEMBLER__ -# define HIDDEN_BUILTIN_JUMPTARGET(name) HIDDEN_JUMPTARGET(name) -#endif - -#if IS_IN (libutil) -# define libutil_hidden_proto(name, attrs...) hidden_proto (name, ##attrs) -# define libutil_hidden_tls_proto(name, attrs...) \ - hidden_tls_proto (name, ##attrs) -# define libutil_hidden_def(name) hidden_def (name) -# define libutil_hidden_weak(name) hidden_weak (name) -# define libutil_hidden_ver(local, name) hidden_ver (local, name) -# define libutil_hidden_data_def(name) hidden_data_def (name) -# define libutil_hidden_data_weak(name) hidden_data_weak (name) -# define libutil_hidden_data_ver(local, name) hidden_data_ver (local, name) -#else -# define libutil_hidden_proto(name, attrs...) -# define libutil_hidden_tls_proto(name, attrs...) -# define libutil_hidden_def(name) -# define libutil_hidden_weak(name) -# define libutil_hidden_ver(local, name) -# define libutil_hidden_data_def(name) -# define libutil_hidden_data_weak(name) -# define libutil_hidden_data_ver(local, name) -#endif - -/* Get some dirty hacks. */ -#include <symbol-hacks.h> - -/* Move compatibility symbols out of the way by placing them all in a - special section. */ -#ifndef __ASSEMBLER__ -# define attribute_compat_text_section \ - __attribute__ ((section (".text.compat"))) -# define attribute_compat_data_section \ - __attribute__ ((section (".data.compat"))) -#else -# define compat_text_section .section ".text.compat", "ax"; -# define compat_data_section .section ".data.compat", "aw"; -#endif - -/* Helper / base macros for indirect function symbols. */ -#define __ifunc_resolver(type_name, name, expr, arg, init, classifier) \ - classifier inhibit_stack_protector void *name##_ifunc (arg) \ - { \ - init (); \ - __typeof (type_name) *res = expr; \ - return res; \ - } - -#ifdef HAVE_GCC_IFUNC -# define __ifunc(type_name, name, expr, arg, init) \ - extern __typeof (type_name) name __attribute__ \ - ((ifunc (#name "_ifunc"))); \ - __ifunc_resolver (type_name, name, expr, arg, init, static) - -# define __ifunc_hidden(type_name, name, expr, arg, init) \ - __ifunc (type_name, name, expr, arg, init) -#else -/* Gcc does not support __attribute__ ((ifunc (...))). Use the old behaviour - as fallback. But keep in mind that the debug information for the ifunc - resolver functions is not correct. It contains the ifunc'ed function as - DW_AT_linkage_name. E.g. lldb uses this field and an inferior function - call of the ifunc'ed function will fail due to "no matching function for - call to ..." because the ifunc'ed function and the resolver function have - different signatures. (Gcc support is disabled at least on a ppc64le - Ubuntu 14.04 system.) */ - -# define __ifunc(type_name, name, expr, arg, init) \ - extern __typeof (type_name) name; \ - void *name##_ifunc (arg) __asm__ (#name); \ - __ifunc_resolver (type_name, name, expr, arg, init,) \ - __asm__ (".type " #name ", %gnu_indirect_function"); - -# define __ifunc_hidden(type_name, name, expr, arg, init) \ - extern __typeof (type_name) __libc_##name; \ - __ifunc (type_name, __libc_##name, expr, arg, init) \ - strong_alias (__libc_##name, name); -#endif /* !HAVE_GCC_IFUNC */ - -/* The following macros are used for indirect function symbols in libc.so. - First of all, you need to have the function prototyped somewhere, - say in foo.h: - - int foo (int __bar); - - If you have an implementation for foo which e.g. uses a special hardware - feature which isn't available on all machines where this libc.so will be - used but decideable if available at runtime e.g. via hwcaps, you can provide - two or multiple implementations of foo: - - int __foo_default (int __bar) - { - return __bar; - } - - int __foo_special (int __bar) - { - return __bar; - } - - If your function foo has no libc_hidden_proto (foo) defined for PLT - bypassing, you can use: - - #define INIT_ARCH() unsigned long int hwcap = __GLRO(dl_hwcap); - - libc_ifunc (foo, (hwcap & HWCAP_SPECIAL) ? __foo_special : __foo_default); - - This will define a resolver function for foo which returns __foo_special or - __foo_default depending on your specified expression. Please note that you - have to define a macro function INIT_ARCH before using libc_ifunc macro as - it is called by the resolver function before evaluating the specified - expression. In this example it is used to prepare the hwcap variable. - The resolver function is assigned to an ifunc'ed symbol foo. Calls to foo - from inside or outside of libc.so will be indirected by a PLT call. - - If your function foo has a libc_hidden_proto (foo) defined for PLT bypassing - and calls to foo within libc.so should always go to one specific - implementation of foo e.g. __foo_default then you have to add: - - __hidden_ver1 (__foo_default, __GI_foo, __foo_default); - - or a tweaked definition of libc_hidden_def macro after the __foo_default - function definition. Calls to foo within libc.so will always go directly to - __foo_default. Calls to foo from outside libc.so will be indirected by a - PLT call to ifunc'ed symbol foo which you have to define in a separate - compile unit: - - #define foo __redirect_foo - #include <foo.h> - #undef foo - - extern __typeof (__redirect_foo) __foo_default attribute_hidden; - extern __typeof (__redirect_foo) __foo_special attribute_hidden; - - libc_ifunc_redirected (__redirect_foo, foo, - (hwcap & HWCAP_SPECIAL) - ? __foo_special - : __foo_default); - - This will define the ifunc'ed symbol foo like above. The redirection of foo - in header file is needed to omit an additional defintion of __GI_foo which - would end in a linker error while linking libc.so. You have to specify - __redirect_foo as first parameter which is used within libc_ifunc_redirected - macro in conjunction with typeof to define the ifunc'ed symbol foo. - - If your function foo has a libc_hidden_proto (foo) defined and calls to foo - within or from outside libc.so should go via ifunc'ed symbol, then you have - to use: - - libc_ifunc_hidden (foo, foo, - (hwcap & HWCAP_SPECIAL) - ? __foo_special - : __foo_default); - libc_hidden_def (foo) - - The first parameter foo of libc_ifunc_hidden macro is used in the same way - as for libc_ifunc_redirected macro. */ - -#define libc_ifunc(name, expr) __ifunc (name, name, expr, void, INIT_ARCH) - -#define libc_ifunc_redirected(redirected_name, name, expr) \ - __ifunc (redirected_name, name, expr, void, INIT_ARCH) - -#define libc_ifunc_hidden(redirected_name, name, expr) \ - __ifunc_hidden (redirected_name, name, expr, void, INIT_ARCH) - -/* The body of the function is supposed to use __get_cpu_features - which will, if necessary, initialize the data first. */ -#define libm_ifunc_init() -#define libm_ifunc(name, expr) \ - __ifunc (name, name, expr, void, libm_ifunc_init) - -/* Add the compiler optimization to inhibit loop transformation to library - calls. This is used to avoid recursive calls in memset and memmove - default implementations. */ -#ifdef HAVE_CC_INHIBIT_LOOP_TO_LIBCALL -# define inhibit_loop_to_libcall \ - __attribute__ ((__optimize__ ("-fno-tree-loop-distribute-patterns"))) -#else -# define inhibit_loop_to_libcall -#endif - -/* These macros facilitate sharing source files with gnulib. - - They are here instead of sys/cdefs.h because they should not be - used in public header files. - - Their definitions should be kept consistent with the definitions in - gnulib-common.m4, but it is not necessary to cater to old non-GCC - compilers, since they will only be used while building glibc itself. - (Note that _GNUC_PREREQ cannot be used in this file.) */ - -/* Define as a marker that can be attached to declarations that might not - be used. This helps to reduce warnings, such as from - GCC -Wunused-parameter. */ -#if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7) -# define _GL_UNUSED __attribute__ ((__unused__)) -#else -# define _GL_UNUSED -#endif - -/* gcc supports the "unused" attribute on possibly unused labels, and - g++ has since version 4.5. Note to support C++ as well as C, - _GL_UNUSED_LABEL should be used with a trailing ; */ -#if !defined __cplusplus || __GNUC__ > 4 \ - || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5) -# define _GL_UNUSED_LABEL _GL_UNUSED -#else -# define _GL_UNUSED_LABEL -#endif - -/* The __pure__ attribute was added in gcc 2.96. */ -#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96) -# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__)) -#else -# define _GL_ATTRIBUTE_PURE /* empty */ -#endif - -/* The __const__ attribute was added in gcc 2.95. */ -#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95) -# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__)) -#else -# define _GL_ATTRIBUTE_CONST /* empty */ -#endif - -#endif /* !_ISOMAC */ -#endif /* libc-symbols.h */ |