diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/libc-symbols.h | 291 |
1 files changed, 157 insertions, 134 deletions
diff --git a/include/libc-symbols.h b/include/libc-symbols.h index 3f29b9463..34be37c5d 100644 --- a/include/libc-symbols.h +++ b/include/libc-symbols.h @@ -200,34 +200,34 @@ # ifdef HAVE_ASM_SET_DIRECTIVE # ifdef HAVE_ASM_GLOBAL_DOT_NAME -# define strong_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original) ASM_LINE_SEP \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_DOT_NAME (alias),C_SYMBOL_DOT_NAME (original) -# define strong_data_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original) +# define strong_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .set C_SYMBOL_NAME(alias),C_SYMBOL_NAME(original) ASM_LINE_SEP \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME(alias) ASM_LINE_SEP \ + .set C_SYMBOL_DOT_NAME(alias),C_SYMBOL_DOT_NAME(original) +# define strong_data_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .set C_SYMBOL_NAME(alias),C_SYMBOL_NAME(original) # else -# define strong_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original) +# define strong_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE 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) # endif # else # ifdef HAVE_ASM_GLOBAL_DOT_NAME -# define strong_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original) -# define strong_data_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) +# define strong_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + C_SYMBOL_NAME(alias) = C_SYMBOL_NAME(original) ASM_LINE_SEP \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME(alias) ASM_LINE_SEP \ + C_SYMBOL_DOT_NAME(alias) = C_SYMBOL_DOT_NAME(original) +# define strong_data_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + C_SYMBOL_NAME(alias) = C_SYMBOL_NAME(original) # else -# define strong_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) +# define strong_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE 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 # endif @@ -235,45 +235,45 @@ # ifdef HAVE_WEAK_SYMBOLS # ifdef HAVE_ASM_WEAKEXT_DIRECTIVE # ifdef HAVE_ASM_GLOBAL_DOT_NAME -# define weak_alias(original, alias) \ - .weakext C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original) ASM_LINE_SEP \ - .weakext C_SYMBOL_DOT_NAME (alias), C_SYMBOL_DOT_NAME (original) +# define weak_alias(original, alias) \ + .weakext C_SYMBOL_NAME(alias),C_SYMBOL_NAME(original) ASM_LINE_SEP \ + .weakext C_SYMBOL_DOT_NAME(alias),C_SYMBOL_DOT_NAME(original) # else -# define weak_alias(original, alias) \ - .weakext C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original) +# define weak_alias(original, alias) \ + .weakext C_SYMBOL_NAME(alias),C_SYMBOL_NAME(original) # endif -# define weak_extern(symbol) \ - .weakext C_SYMBOL_NAME (symbol) +# define weak_extern(symbol) \ + .weakext C_SYMBOL_NAME(symbol) # else /* ! HAVE_ASM_WEAKEXT_DIRECTIVE */ # ifdef HAVE_ASM_SET_DIRECTIVE # ifdef HAVE_ASM_GLOBAL_DOT_NAME -# define weak_alias(original, alias) \ - .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original) ASM_LINE_SEP \ - .weak C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_DOT_NAME (alias), C_SYMBOL_DOT_NAME (original) +# define weak_alias(original, alias) \ + .weak C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .set C_SYMBOL_NAME(alias),C_SYMBOL_NAME(original) ASM_LINE_SEP \ + .weak C_SYMBOL_DOT_NAME(alias) ASM_LINE_SEP \ + .set C_SYMBOL_DOT_NAME(alias),C_SYMBOL_DOT_NAME(original) # else -# define weak_alias(original, alias) \ - .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_NAME (alias), C_SYMBOL_NAME (original) +# define weak_alias(original, alias) \ + .weak C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .set C_SYMBOL_NAME(alias),C_SYMBOL_NAME(original) # endif # else /* ! HAVE_ASM_SET_DIRECTIVE */ # ifdef HAVE_ASM_GLOBAL_DOT_NAME -# define weak_alias(original, alias) \ - .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP \ - .weak C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original) +# define weak_alias(original, alias) \ + .weak C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + C_SYMBOL_NAME(alias) = C_SYMBOL_NAME(original) ASM_LINE_SEP \ + .weak C_SYMBOL_DOT_NAME(alias) ASM_LINE_SEP \ + C_SYMBOL_DOT_NAME(alias) = C_SYMBOL_DOT_NAME(original) # else -# define weak_alias(original, alias) \ - .weak C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) +# define weak_alias(original, alias) \ + .weak C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + C_SYMBOL_NAME(alias) = C_SYMBOL_NAME(original) # endif # endif -# define weak_extern(symbol) \ - .weak C_SYMBOL_NAME (symbol) +# define weak_extern(symbol) \ + .weak C_SYMBOL_NAME(symbol) # endif /* ! HAVE_ASM_WEAKEXT_DIRECTIVE */ @@ -285,6 +285,7 @@ #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. */ @@ -292,10 +293,12 @@ # define internal_function /* empty */ #endif + /* 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#APP\n\t#" to the section name makes gcc put it's bogus section attributes on what looks like a comment to the assembler. */ #ifdef __sparc__ /* HAVE_SECTION_QUOTES */ @@ -304,6 +307,7 @@ # define __sec_comment "\n#APP\n\t#" #endif + /* When a reference to SYMBOL is encountered, the linker will emit a warning message MSG. */ #define link_warning(symbol, msg) \ @@ -317,8 +321,7 @@ #ifdef SHARED # define INTUSE(name) name##_internal # define INTDEF(name) strong_alias (name, name##_internal) -# define INTVARDEF(name) \ - _INTVARDEF (name, name##_internal) +# define INTVARDEF(name) _INTVARDEF (name, name##_internal) # if defined HAVE_VISIBILITY_ATTRIBUTE # define _INTVARDEF(name, aliasname) \ extern __typeof (name) aliasname __attribute__ ((alias (#name), \ @@ -337,65 +340,61 @@ # define INTVARDEF2(name, newname) #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) + int foo(int __bar); + libc_hidden_proto(foo) line and after the foo function definition: - int foo (int __bar) - { + int foo(int __bar) { return __bar; } - libc_hidden_def (foo) + libc_hidden_def(foo) or - int foo (int __bar) - { + int foo(int __bar) { return __bar; } - libc_hidden_weak (foo) + 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: + 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: - libc_hidden_proto (foo) + extern int foo; + libc_hidden_proto(foo) - line and after foo's definition: + and after foo's definition: int foo = INITIAL_FOO_VALUE; - libc_hidden_data_def (foo) + libc_hidden_data_def(foo) or int foo = INITIAL_FOO_VALUE; - libc_hidden_data_weak (foo) + 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) - { + int baz(int __bar) { return __bar; } - strong_alias (baz, foo) - libc_hidden_weak (foo) + 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 !defined NOT_IN_libc || defined IS_IN_rtld - hidden_proto (foo) + hidden_proto(foo) #endif in include/foo.h and the normal macros at all function definitions @@ -404,29 +403,47 @@ If versioned_symbol macro is used to define foo, libc_hidden_ver macro should be used, as in: - int __real_foo (int __bar) - { + int __real_foo(int __bar) { return __bar; } - versioned_symbol (libc, __real_foo, foo, GLIBC_2_1); - libc_hidden_ver (__real_foo, foo) */ + versioned_symbol(libc, __real_foo, foo, GLIBC_2_1); + libc_hidden_ver(__real_foo, foo) + */ /* uClibc specific (the above comment was copied from glibc): - * a. when ppc64 will be supported, we need changes to support: + * + * when ppc64 will be supported, we need changes to support * strong_data_alias (used by asm hidden_data_def) - * b. libc_hidden_proto(foo) should be added after the header having foo's prototype - * or after extern foo... to all source files that should use the internal version - * of foo within libc, even to the file defining foo itself, libc_hidden_def does - * not hide __GI_foo itself, although the name suggests it (hiding is done exclusively - * by libc_hidden_proto). The reasoning to have it after the header w/ foo's prototype is - * to get first the __REDIRECT from original header and then create the __GI_foo alias - * c. no versioning support, hidden[_data]_ver are noop - * d. hidden_def() in asm is _hidden_strong_alias (not strong_alias) */ - -/* Arrange to hide uClibc internals */ -#if (defined __GNUC__ && \ - (defined __GNUC_MINOR__ && ( __GNUC__ >= 3 && __GNUC_MINOR__ >= 3 ) \ - || __GNUC__ >= 4)) || defined __ICC + * + * no versioning support, hidden[_data]_ver are noop + * + * hidden_def() in asm is _hidden_strong_alias (not strong_alias) + * + * libc_hidden_proto(foo) should be added after declaration + * in the header, or after extern foo... in all source files + * (this is discouraged). + * libc_hidden_def does not hide __GI_foo itself, although the name + * suggests it (hiding is done exclusively by libc_hidden_proto). + +FIXME! - ? + * The reasoning to have it after the header w/ foo's prototype is + * to get first the __REDIRECT from original header and then create + * the __GI_foo alias + + * Hunt for references which still go through PLT (example for x86): + * build shared lib, then disassemble it and search for <xxx@plt>: + * $ objdump -drx libuClibc-*.so >disasm.txt + * $ grep -F '@plt>:' disasm.txt + * + * In uclibc, malloc/free and related functions should be called + * through PLT (making it possible to use alternative malloc), + * and possibly some __pthread_xxx functions can be called through PLT + * (why?). The rest should not use PLT. + */ + +#if (defined __GNUC__ && defined __GNUC_MINOR__ \ + && (( __GNUC__ >= 3 && __GNUC_MINOR__ >= 3) || __GNUC__ >= 4) \ + ) || defined __ICC # define attribute_hidden __attribute__ ((visibility ("hidden"))) # define __hidden_proto_hiddenattr(attrs...) __attribute__ ((visibility ("hidden"), ##attrs)) #else @@ -435,67 +452,69 @@ #endif #if /*!defined STATIC &&*/ !defined __BCC__ + # ifndef __ASSEMBLER__ # define hidden_proto(name, attrs...) __hidden_proto (name, __GI_##name, ##attrs) # define __hidden_proto(name, internal, attrs...) \ - extern __typeof (name) name __asm__ (__hidden_asmname (#internal)) \ - __hidden_proto_hiddenattr (attrs); + extern __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_asmname1 (,#local)))) + extern __typeof (name) __EI_##name __asm__(__hidden_asmname (#internal)); \ + extern __typeof (name) __EI_##name __attribute__((alias (__hidden_asmname1 (,#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) \ +# define hidden_weak(name) \ __hidden_ver1(__GI_##name, name, name) __attribute__((weak)); # define hidden_data_weak(name) hidden_weak(name) # else /* __ASSEMBLER__ */ -# ifdef HAVE_ASM_SET_DIRECTIVE -# ifdef HAVE_ASM_GLOBAL_DOT_NAME -# define _hidden_strong_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .hidden C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original) ASM_LINE_SEP \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \ - .hidden C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_DOT_NAME (alias),C_SYMBOL_DOT_NAME (original) -# else -# define _hidden_strong_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .hidden C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .set C_SYMBOL_NAME (alias),C_SYMBOL_NAME (original) -# endif -# else -# ifdef HAVE_ASM_GLOBAL_DOT_NAME -# define _hidden_strong_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .hidden C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) ASM_LINE_SEP \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \ - .hidden C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_DOT_NAME (alias) = C_SYMBOL_DOT_NAME (original) -# else -# define _hidden_strong_alias(original, alias) \ - ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .hidden C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - C_SYMBOL_NAME (alias) = C_SYMBOL_NAME (original) + +# ifdef HAVE_ASM_SET_DIRECTIVE +# ifdef HAVE_ASM_GLOBAL_DOT_NAME +# define _hidden_strong_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .hidden C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .set C_SYMBOL_NAME(alias),C_SYMBOL_NAME(original) ASM_LINE_SEP \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME(alias) ASM_LINE_SEP \ + .hidden C_SYMBOL_DOT_NAME(alias) ASM_LINE_SEP \ + .set C_SYMBOL_DOT_NAME(alias),C_SYMBOL_DOT_NAME(original) +# else +# define _hidden_strong_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .hidden C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .set C_SYMBOL_NAME(alias),C_SYMBOL_NAME(original) +# endif +# else /* dont have .set directive */ +# ifdef HAVE_ASM_GLOBAL_DOT_NAME +# define _hidden_strong_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .hidden C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + C_SYMBOL_NAME(alias) = C_SYMBOL_NAME(original) ASM_LINE_SEP \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_DOT_NAME(alias) ASM_LINE_SEP \ + .hidden C_SYMBOL_DOT_NAME(alias) ASM_LINE_SEP \ + C_SYMBOL_DOT_NAME(alias) = C_SYMBOL_DOT_NAME(original) +# else +# define _hidden_strong_alias(original, alias) \ + ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .hidden C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + C_SYMBOL_NAME(alias) = C_SYMBOL_NAME(original) +# endif # endif -# endif # ifdef HAVE_ASM_GLOBAL_DOT_NAME -# define _hidden_weak_alias(original, alias) \ - .hidden C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - .hidden C_SYMBOL_DOT_NAME (alias) ASM_LINE_SEP \ - weak_alias(original, alias) +# define _hidden_weak_alias(original, alias) \ + .hidden C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + .hidden C_SYMBOL_DOT_NAME(alias) ASM_LINE_SEP \ + weak_alias(original, alias) # else -# define _hidden_weak_alias(original, alias) \ - .hidden C_SYMBOL_NAME (alias) ASM_LINE_SEP \ - weak_alias(original, alias) +# define _hidden_weak_alias(original, alias) \ + .hidden C_SYMBOL_NAME(alias) ASM_LINE_SEP \ + weak_alias(original, alias) # endif /* For assembly, we need to do the opposite of what we do in C: @@ -519,19 +538,23 @@ # define HIDDEN_JUMPTARGET(name) __GI_##name # endif # endif /* __ASSEMBLER__ */ -#else /* SHARED */ + +#else /* not SHARED */ + # ifndef __ASSEMBLER__ # define hidden_proto(name, attrs...) # else # define HIDDEN_JUMPTARGET(name) name -# endif /* Not __ASSEMBLER__ */ +# 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) -#endif /* SHARED */ + +#endif /* SHARED / not SHARED */ + /* uClibc does not support versioning yet. */ #define versioned_symbol(lib, local, symbol, version) /* weak_alias(local, symbol) */ |