* elf/dl-lookup.c (_dl_debug_bindings): Remove unised symbol_scope
[glibc.git] / sysdeps / generic / ldsodefs.h
blob4fa3c0114a4be5f6c7aa3b278fdb436c03e642fe
1 /* Run-time dynamic linker data structures for loaded ELF shared objects.
2 Copyright (C) 1995-2003, 2004, 2005, 2006 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
20 #ifndef _LDSODEFS_H
21 #define _LDSODEFS_H 1
23 #include <features.h>
25 #include <stdbool.h>
26 #define __need_size_t
27 #define __need_NULL
28 #include <stddef.h>
29 #include <string.h>
31 #include <elf.h>
32 #include <dlfcn.h>
33 #include <fpu_control.h>
34 #include <sys/mman.h>
35 #include <link.h>
36 #include <dl-lookupcfg.h>
37 #include <dl-sysdep.h>
38 #include <bits/libc-lock.h>
39 #include <hp-timing.h>
40 #include <tls.h>
41 #include <rtld-lowlevel.h>
43 __BEGIN_DECLS
45 /* We use this macro to refer to ELF types independent of the native wordsize.
46 `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'. */
47 #define ELFW(type) _ElfW (ELF, __ELF_NATIVE_CLASS, type)
49 /* All references to the value of l_info[DT_PLTGOT],
50 l_info[DT_STRTAB], l_info[DT_SYMTAB], l_info[DT_RELA],
51 l_info[DT_REL], l_info[DT_JMPREL], and l_info[VERSYMIDX (DT_VERSYM)]
52 have to be accessed via the D_PTR macro. The macro is needed since for
53 most architectures the entry is already relocated - but for some not
54 and we need to relocate at access time. */
55 #ifdef DL_RO_DYN_SECTION
56 # define D_PTR(map, i) ((map)->i->d_un.d_ptr + (map)->l_addr)
57 #else
58 # define D_PTR(map, i) (map)->i->d_un.d_ptr
59 #endif
61 /* Result of the lookup functions and how to retrieve the base address. */
62 typedef struct link_map *lookup_t;
63 #define LOOKUP_VALUE(map) map
64 #define LOOKUP_VALUE_ADDRESS(map) ((map) ? (map)->l_addr : 0)
66 /* On some architectures a pointer to a function is not just a pointer
67 to the actual code of the function but rather an architecture
68 specific descriptor. */
69 #ifndef ELF_FUNCTION_PTR_IS_SPECIAL
70 # define DL_SYMBOL_ADDRESS(map, ref) \
71 (void *) (LOOKUP_VALUE_ADDRESS (map) + ref->st_value)
72 # define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr))
73 # define DL_DT_INIT_ADDRESS(map, start) (start)
74 # define DL_DT_FINI_ADDRESS(map, start) (start)
75 #endif
77 /* On some architectures dladdr can't use st_size of all symbols this way. */
78 #define DL_ADDR_SYM_MATCH(L, SYM, MATCHSYM, ADDR) \
79 ((ADDR) >= (L)->l_addr + (SYM)->st_value \
80 && ((((SYM)->st_shndx == SHN_UNDEF || (SYM)->st_size == 0) \
81 && (ADDR) == (L)->l_addr + (SYM)->st_value) \
82 || (ADDR) < (L)->l_addr + (SYM)->st_value + (SYM)->st_size) \
83 && ((MATCHSYM) == NULL || (MATCHSYM)->st_value < (SYM)->st_value))
85 /* Unmap a loaded object, called by _dl_close (). */
86 #ifndef DL_UNMAP_IS_SPECIAL
87 # define DL_UNMAP(map) \
88 __munmap ((void *) (map)->l_map_start, \
89 (map)->l_map_end - (map)->l_map_start)
90 #endif
92 /* By default we do not need special support to initialize DSOs loaded
93 by statically linked binaries. */
94 #ifndef DL_STATIC_INIT
95 # define DL_STATIC_INIT(map)
96 #endif
98 /* Reloc type classes as returned by elf_machine_type_class().
99 ELF_RTYPE_CLASS_PLT means this reloc should not be satisfied by
100 some PLT symbol, ELF_RTYPE_CLASS_COPY means this reloc should not be
101 satisfied by any symbol in the executable. Some architectures do
102 not support copy relocations. In this case we define the macro to
103 zero so that the code for handling them gets automatically optimized
104 out. */
105 #define ELF_RTYPE_CLASS_PLT 1
106 #ifndef DL_NO_COPY_RELOCS
107 # define ELF_RTYPE_CLASS_COPY 2
108 #else
109 # define ELF_RTYPE_CLASS_COPY 0
110 #endif
112 /* ELF uses the PF_x macros to specify the segment permissions, mmap
113 uses PROT_xxx. In most cases the three macros have the values 1, 2,
114 and 3 but not in a matching order. The following macros allows
115 converting from the PF_x values to PROT_xxx values. */
116 #define PF_TO_PROT \
117 ((PROT_READ << (PF_R * 4)) \
118 | (PROT_WRITE << (PF_W * 4)) \
119 | (PROT_EXEC << (PF_X * 4)) \
120 | ((PROT_READ | PROT_WRITE) << ((PF_R | PF_W) * 4)) \
121 | ((PROT_READ | PROT_EXEC) << ((PF_R | PF_X) * 4)) \
122 | ((PROT_WRITE | PROT_EXEC) << (PF_W | PF_X) * 4) \
123 | ((PROT_READ | PROT_WRITE | PROT_EXEC) << ((PF_R | PF_W | PF_X) * 4)))
126 /* For the version handling we need an array with only names and their
127 hash values. */
128 struct r_found_version
130 const char *name;
131 ElfW(Word) hash;
133 int hidden;
134 const char *filename;
137 /* We want to cache information about the searches for shared objects. */
139 enum r_dir_status { unknown, nonexisting, existing };
141 struct r_search_path_elem
143 /* This link is only used in the `all_dirs' member of `r_search_path'. */
144 struct r_search_path_elem *next;
146 /* Strings saying where the definition came from. */
147 const char *what;
148 const char *where;
150 /* Basename for this search path element. The string must end with
151 a slash character. */
152 const char *dirname;
153 size_t dirnamelen;
155 enum r_dir_status status[0];
158 struct r_strlenpair
160 const char *str;
161 size_t len;
165 /* A data structure for a simple single linked list of strings. */
166 struct libname_list
168 const char *name; /* Name requested (before search). */
169 struct libname_list *next; /* Link to next name for this object. */
170 int dont_free; /* Flag whether this element should be freed
171 if the object is not entirely unloaded. */
175 /* Bit masks for the objects which valid callers can come from to
176 functions with restricted interface. */
177 enum allowmask
179 allow_libc = 1,
180 allow_libdl = 2,
181 allow_libpthread = 4,
182 allow_ldso = 8
186 /* Type for list of auditing interfaces. */
187 struct La_i86_regs;
188 struct La_i86_retval;
189 struct La_x86_64_regs;
190 struct La_x86_64_retval;
191 struct La_ppc32_regs;
192 struct La_ppc32_retval;
193 struct La_ppc64_regs;
194 struct La_ppc64_retval;
195 struct La_sh_regs;
196 struct La_sh_retval;
197 struct La_alpha_regs;
198 struct La_alpha_retval;
199 struct La_s390_32_regs;
200 struct La_s390_32_retval;
201 struct La_s390_64_regs;
202 struct La_s390_64_retval;
203 struct La_ia64_regs;
204 struct La_ia64_retval;
205 struct La_sparc32_regs;
206 struct La_sparc32_retval;
207 struct La_sparc64_regs;
208 struct La_sparc64_retval;
210 struct audit_ifaces
212 void (*activity) (uintptr_t *, unsigned int);
213 char *(*objsearch) (const char *, uintptr_t *, unsigned int);
214 unsigned int (*objopen) (struct link_map *, Lmid_t, uintptr_t *);
215 void (*preinit) (uintptr_t *);
216 union
218 uintptr_t (*symbind32) (Elf32_Sym *, unsigned int, uintptr_t *,
219 uintptr_t *, unsigned int *, const char *);
220 uintptr_t (*symbind64) (Elf64_Sym *, unsigned int, uintptr_t *,
221 uintptr_t *, unsigned int *, const char *);
223 union
225 Elf32_Addr (*i86_gnu_pltenter) (Elf32_Sym *, unsigned int, uintptr_t *,
226 uintptr_t *, struct La_i86_regs *,
227 unsigned int *, const char *name,
228 long int *framesizep);
229 Elf64_Addr (*x86_64_gnu_pltenter) (Elf64_Sym *, unsigned int, uintptr_t *,
230 uintptr_t *, struct La_x86_64_regs *,
231 unsigned int *, const char *name,
232 long int *framesizep);
233 Elf32_Addr (*ppc32_gnu_pltenter) (Elf32_Sym *, unsigned int, uintptr_t *,
234 uintptr_t *, struct La_ppc32_regs *,
235 unsigned int *, const char *name,
236 long int *framesizep);
237 Elf64_Addr (*ppc64_gnu_pltenter) (Elf64_Sym *, unsigned int, uintptr_t *,
238 uintptr_t *, struct La_ppc64_regs *,
239 unsigned int *, const char *name,
240 long int *framesizep);
241 uintptr_t (*sh_gnu_pltenter) (Elf32_Sym *, unsigned int, uintptr_t *,
242 uintptr_t *, const struct La_sh_regs *,
243 unsigned int *, const char *name,
244 long int *framesizep);
245 Elf64_Addr (*alpha_gnu_pltenter) (Elf64_Sym *, unsigned int, uintptr_t *,
246 uintptr_t *, struct La_alpha_regs *,
247 unsigned int *, const char *name,
248 long int *framesizep);
249 Elf32_Addr (*s390_32_gnu_pltenter) (Elf32_Sym *, unsigned int, uintptr_t *,
250 uintptr_t *, struct La_s390_32_regs *,
251 unsigned int *, const char *name,
252 long int *framesizep);
253 Elf64_Addr (*s390_64_gnu_pltenter) (Elf64_Sym *, unsigned int, uintptr_t *,
254 uintptr_t *, struct La_s390_64_regs *,
255 unsigned int *, const char *name,
256 long int *framesizep);
257 Elf64_Addr (*ia64_gnu_pltenter) (Elf64_Sym *, unsigned int, uintptr_t *,
258 uintptr_t *, struct La_ia64_regs *,
259 unsigned int *, const char *name,
260 long int *framesizep);
261 Elf32_Addr (*sparc32_gnu_pltenter) (Elf32_Sym *, unsigned int,
262 uintptr_t *, uintptr_t *,
263 const struct La_sparc32_regs *,
264 unsigned int *, const char *name,
265 long int *framesizep);
266 Elf64_Addr (*sparc64_gnu_pltenter) (Elf64_Sym *, unsigned int,
267 uintptr_t *, uintptr_t *,
268 const struct La_sparc64_regs *,
269 unsigned int *, const char *name,
270 long int *framesizep);
271 #ifdef ARCH_PLTENTER_MEMBERS
272 ARCH_PLTENTER_MEMBERS;
273 #endif
275 union
277 unsigned int (*i86_gnu_pltexit) (Elf32_Sym *, unsigned int, uintptr_t *,
278 uintptr_t *, const struct La_i86_regs *,
279 struct La_i86_retval *, const char *);
280 unsigned int (*x86_64_gnu_pltexit) (Elf64_Sym *, unsigned int, uintptr_t *,
281 uintptr_t *,
282 const struct La_x86_64_regs *,
283 struct La_x86_64_retval *,
284 const char *);
285 unsigned int (*ppc32_gnu_pltexit) (Elf32_Sym *, unsigned int, uintptr_t *,
286 uintptr_t *,
287 const struct La_ppc32_regs *,
288 struct La_ppc32_retval *, const char *);
289 unsigned int (*ppc64_gnu_pltexit) (Elf64_Sym *, unsigned int, uintptr_t *,
290 uintptr_t *,
291 const struct La_ppc64_regs *,
292 struct La_ppc64_retval *, const char *);
293 unsigned int (*sh_gnu_pltexit) (Elf32_Sym *, unsigned int, uintptr_t *,
294 uintptr_t *, const struct La_sh_regs *,
295 struct La_sh_retval *, const char *);
296 unsigned int (*alpha_gnu_pltexit) (Elf64_Sym *, unsigned int, uintptr_t *,
297 uintptr_t *,
298 const struct La_alpha_regs *,
299 struct La_alpha_retval *, const char *);
300 unsigned int (*s390_32_gnu_pltexit) (Elf32_Sym *, unsigned int,
301 uintptr_t *, uintptr_t *,
302 const struct La_s390_32_regs *,
303 struct La_s390_32_retval *,
304 const char *);
305 unsigned int (*s390_64_gnu_pltexit) (Elf64_Sym *, unsigned int,
306 uintptr_t *, uintptr_t *,
307 const struct La_s390_64_regs *,
308 struct La_s390_64_retval *,
309 const char *);
310 unsigned int (*ia64_gnu_pltexit) (Elf64_Sym *, unsigned int, uintptr_t *,
311 uintptr_t *,
312 const struct La_ia64_regs *,
313 struct La_ia64_retval *, const char *);
314 unsigned int (*sparc32_gnu_pltexit) (Elf32_Sym *, unsigned int,
315 uintptr_t *, uintptr_t *,
316 const struct La_sparc32_regs *,
317 struct La_sparc32_retval *,
318 const char *);
319 unsigned int (*sparc64_gnu_pltexit) (Elf64_Sym *, unsigned int,
320 uintptr_t *, uintptr_t *,
321 const struct La_sparc32_regs *,
322 struct La_sparc32_retval *,
323 const char *);
324 #ifdef ARCH_PLTEXIT_MEMBERS
325 ARCH_PLTEXIT_MEMBERS;
326 #endif
328 unsigned int (*objclose) (uintptr_t *);
330 struct audit_ifaces *next;
334 /* Test whether given NAME matches any of the names of the given object. */
335 extern int _dl_name_match_p (const char *__name, const struct link_map *__map)
336 internal_function;
338 /* Function used as argument for `_dl_receive_error' function. The
339 arguments are the error code, error string, and the objname the
340 error occurred in. */
341 typedef void (*receiver_fct) (int, const char *, const char *);
343 /* Internal functions of the run-time dynamic linker.
344 These can be accessed if you link again the dynamic linker
345 as a shared library, as in `-lld' or `/lib/ld.so' explicitly;
346 but are not normally of interest to user programs.
348 The `-ldl' library functions in <dlfcn.h> provide a simple
349 user interface to run-time dynamic linking. */
352 #ifndef SHARED
353 # define EXTERN extern
354 # define GL(name) _##name
355 #else
356 # define EXTERN
357 # ifdef IS_IN_rtld
358 # define GL(name) _rtld_local._##name
359 # else
360 # define GL(name) _rtld_global._##name
361 # endif
362 struct rtld_global
364 #endif
365 /* Don't change the order of the following elements. 'dl_loaded'
366 must remain the first element. Forever. */
368 /* Non-shared code has no support for multiple namespaces. */
369 #ifdef SHARED
370 # define DL_NNS 16
371 #else
372 # define DL_NNS 1
373 #endif
374 EXTERN struct link_namespaces
376 /* A pointer to the map for the main map. */
377 struct link_map *_ns_loaded;
378 /* Number of object in the _dl_loaded list. */
379 unsigned int _ns_nloaded;
380 /* Direct pointer to the searchlist of the main object. */
381 struct r_scope_elem *_ns_main_searchlist;
382 /* This is zero at program start to signal that the global scope map is
383 allocated by rtld. Later it keeps the size of the map. It might be
384 reset if in _dl_close if the last global object is removed. */
385 size_t _ns_global_scope_alloc;
386 /* Keep track of changes to each namespace' list. */
387 struct r_debug _ns_debug;
388 } _dl_ns[DL_NNS];
390 /* During the program run we must not modify the global data of
391 loaded shared object simultanously in two threads. Therefore we
392 protect `_dl_open' and `_dl_close' in dl-close.c.
394 This must be a recursive lock since the initializer function of
395 the loaded object might as well require a call to this function.
396 At this time it is not anymore a problem to modify the tables. */
397 __rtld_lock_define_recursive (EXTERN, _dl_load_lock)
399 /* Incremented whenever something may have been added to dl_loaded. */
400 EXTERN unsigned long long _dl_load_adds;
402 #ifndef MAP_ANON
403 /* File descriptor referring to the zero-fill device. */
404 EXTERN int _dl_zerofd;
405 #endif
407 /* The object to be initialized first. */
408 EXTERN struct link_map *_dl_initfirst;
410 #if HP_TIMING_AVAIL || HP_SMALL_TIMING_AVAIL
411 /* Start time on CPU clock. */
412 EXTERN hp_timing_t _dl_cpuclock_offset;
413 #endif
415 /* Map of shared object to be profiled. */
416 EXTERN struct link_map *_dl_profile_map;
418 /* Counters for the number of relocations performed. */
419 EXTERN unsigned long int _dl_num_relocations;
420 EXTERN unsigned long int _dl_num_cache_relocations;
422 /* List of search directories. */
423 EXTERN struct r_search_path_elem *_dl_all_dirs;
425 #ifdef _LIBC_REENTRANT
426 EXTERN void **(*_dl_error_catch_tsd) (void) __attribute__ ((const));
427 #endif
429 /* Structure describing the dynamic linker itself. We need to
430 reserve memory for the data the audit libraries need. */
431 EXTERN struct link_map _dl_rtld_map;
432 #ifdef SHARED
433 struct auditstate audit_data[DL_NNS];
434 #endif
436 #if defined SHARED && defined _LIBC_REENTRANT \
437 && defined __rtld_lock_default_lock_recursive
438 EXTERN void (*_dl_rtld_lock_recursive) (void *);
439 EXTERN void (*_dl_rtld_unlock_recursive) (void *);
440 #endif
442 /* Prevailing state of the stack, PF_X indicating it's executable. */
443 EXTERN ElfW(Word) _dl_stack_flags;
445 /* If loading a shared object requires that we make the stack executable
446 when it was not, we do it by calling this function.
447 It returns an errno code or zero on success. */
448 EXTERN int (*_dl_make_stack_executable_hook) (void **) internal_function;
450 /* Keep the conditional TLS members at the end so the layout of the
451 structure used by !USE_TLS code matches the prefix of the layout in
452 the USE_TLS rtld. Note that `struct link_map' is conditionally
453 defined as well, so _dl_rtld_map needs to be last before this. */
454 #ifdef USE_TLS
455 /* Highest dtv index currently needed. */
456 EXTERN size_t _dl_tls_max_dtv_idx;
457 /* Flag signalling whether there are gaps in the module ID allocation. */
458 EXTERN bool _dl_tls_dtv_gaps;
459 /* Information about the dtv slots. */
460 EXTERN struct dtv_slotinfo_list
462 size_t len;
463 struct dtv_slotinfo_list *next;
464 struct dtv_slotinfo
466 size_t gen;
467 struct link_map *map;
468 } slotinfo[0];
469 } *_dl_tls_dtv_slotinfo_list;
470 /* Number of modules in the static TLS block. */
471 EXTERN size_t _dl_tls_static_nelem;
472 /* Size of the static TLS block. */
473 EXTERN size_t _dl_tls_static_size;
474 /* Size actually allocated in the static TLS block. */
475 EXTERN size_t _dl_tls_static_used;
476 /* Alignment requirement of the static TLS block. */
477 EXTERN size_t _dl_tls_static_align;
479 /* Number of additional entries in the slotinfo array of each slotinfo
480 list element. A large number makes it almost certain take we never
481 have to iterate beyond the first element in the slotinfo list. */
482 # define TLS_SLOTINFO_SURPLUS (62)
484 /* Number of additional slots in the dtv allocated. */
485 # define DTV_SURPLUS (14)
487 /* Initial dtv of the main thread, not allocated with normal malloc. */
488 EXTERN void *_dl_initial_dtv;
489 /* Generation counter for the dtv. */
490 EXTERN size_t _dl_tls_generation;
492 EXTERN void (*_dl_init_static_tls) (struct link_map *);
493 #endif
495 #ifdef SHARED
497 # define __rtld_global_attribute__
498 # ifdef IS_IN_rtld
499 # ifdef HAVE_VISIBILITY_ATTRIBUTE
500 # ifdef HAVE_SDATA_SECTION
501 # define __rtld_local_attribute__ \
502 __attribute__ ((visibility ("hidden"), section (".sdata")))
503 # undef __rtld_global_attribute__
504 # define __rtld_global_attribute__ __attribute__ ((section (".sdata")))
505 # else
506 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
507 # endif
508 # else
509 # define __rtld_local_attribute__
510 # endif
511 extern struct rtld_global _rtld_local __rtld_local_attribute__;
512 # undef __rtld_local_attribute__
513 # endif
514 extern struct rtld_global _rtld_global __rtld_global_attribute__;
515 # undef __rtld_global_attribute__
516 #endif
518 #ifndef SHARED
519 # define GLRO(name) _##name
520 #else
521 # ifdef IS_IN_rtld
522 # define GLRO(name) _rtld_local_ro._##name
523 # else
524 # define GLRO(name) _rtld_global_ro._##name
525 # endif
526 struct rtld_global_ro
528 #endif
530 /* If nonzero the appropriate debug information is printed. */
531 EXTERN int _dl_debug_mask;
532 #define DL_DEBUG_LIBS (1 << 0)
533 #define DL_DEBUG_IMPCALLS (1 << 1)
534 #define DL_DEBUG_BINDINGS (1 << 2)
535 #define DL_DEBUG_SYMBOLS (1 << 3)
536 #define DL_DEBUG_VERSIONS (1 << 4)
537 #define DL_DEBUG_RELOC (1 << 5)
538 #define DL_DEBUG_FILES (1 << 6)
539 #define DL_DEBUG_STATISTICS (1 << 7)
540 #define DL_DEBUG_UNUSED (1 << 8)
541 /* These two are used only internally. */
542 #define DL_DEBUG_HELP (1 << 9)
543 #define DL_DEBUG_PRELINK (1 << 10)
545 /* Cached value of `getpagesize ()'. */
546 EXTERN size_t _dl_pagesize;
548 /* OS version. */
549 EXTERN unsigned int _dl_osversion;
550 /* Platform name. */
551 EXTERN const char *_dl_platform;
552 EXTERN size_t _dl_platformlen;
554 /* Copy of the content of `_dl_main_searchlist' at startup time. */
555 EXTERN struct r_scope_elem _dl_initial_searchlist;
557 /* CLK_TCK as reported by the kernel. */
558 EXTERN int _dl_clktck;
560 /* If nonzero print warnings messages. */
561 EXTERN int _dl_verbose;
563 /* File descriptor to write debug messages to. */
564 EXTERN int _dl_debug_fd;
566 /* Do we do lazy relocations? */
567 EXTERN int _dl_lazy;
569 /* Nonzero if runtime lookups should not update the .got/.plt. */
570 EXTERN int _dl_bind_not;
572 /* Nonzero if references should be treated as weak during runtime
573 linking. */
574 EXTERN int _dl_dynamic_weak;
576 /* Default floating-point control word. */
577 EXTERN fpu_control_t _dl_fpu_control;
579 /* Expected cache ID. */
580 EXTERN int _dl_correct_cache_id;
582 /* 0 if internal pointer values should not be guarded, 1 if they should. */
583 EXTERN int _dl_pointer_guard;
585 /* Mask for hardware capabilities that are available. */
586 EXTERN uint64_t _dl_hwcap;
588 /* Mask for important hardware capabilities we honour. */
589 EXTERN uint64_t _dl_hwcap_mask;
591 /* Get architecture specific definitions. */
592 #define PROCINFO_DECL
593 #ifndef PROCINFO_CLASS
594 # define PROCINFO_CLASS EXTERN
595 #endif
596 #include <dl-procinfo.c>
598 /* Names of shared object for which the RPATH should be ignored. */
599 EXTERN const char *_dl_inhibit_rpath;
601 /* Location of the binary. */
602 EXTERN const char *_dl_origin_path;
604 /* -1 if the dynamic linker should honor library load bias,
605 0 if not, -2 use the default (honor biases for normal
606 binaries, don't honor for PIEs). */
607 EXTERN ElfW(Addr) _dl_use_load_bias;
609 /* Name of the shared object to be profiled (if any). */
610 EXTERN const char *_dl_profile;
611 /* Filename of the output file. */
612 EXTERN const char *_dl_profile_output;
613 /* Name of the object we want to trace the prelinking. */
614 EXTERN const char *_dl_trace_prelink;
615 /* Map of shared object to be prelink traced. */
616 EXTERN struct link_map *_dl_trace_prelink_map;
618 /* All search directories defined at startup. */
619 EXTERN struct r_search_path_elem *_dl_init_all_dirs;
621 #if HP_TIMING_AVAIL || HP_SMALL_TIMING_AVAIL
622 /* Overhead of a high-precision timing measurement. */
623 EXTERN hp_timing_t _dl_hp_timing_overhead;
624 #endif
626 #ifdef NEED_DL_SYSINFO
627 /* Syscall handling improvements. This is very specific to x86. */
628 EXTERN uintptr_t _dl_sysinfo;
629 #endif
631 #if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO
632 /* The vsyscall page is a virtual DSO pre-mapped by the kernel.
633 This points to its ELF header. */
634 EXTERN const ElfW(Ehdr) *_dl_sysinfo_dso;
636 /* At startup time we set up the normal DSO data structure for it,
637 and this points to it. */
638 EXTERN struct link_map *_dl_sysinfo_map;
639 #endif
641 #ifdef SHARED
642 /* We add a function table to _rtld_global which is then used to
643 call the function instead of going through the PLT. The result
644 is that we can avoid exporting the functions and we do not jump
645 PLT relocations in libc.so. */
646 void (*_dl_debug_printf) (const char *, ...)
647 __attribute__ ((__format__ (__printf__, 1, 2)));
648 int (internal_function *_dl_catch_error) (const char **, const char **,
649 bool *, void (*) (void *), void *);
650 void (internal_function *_dl_signal_error) (int, const char *, const char *,
651 const char *);
652 void (*_dl_mcount) (ElfW(Addr) frompc, ElfW(Addr) selfpc);
653 lookup_t (internal_function *_dl_lookup_symbol_x) (const char *,
654 struct link_map *,
655 const ElfW(Sym) **,
656 struct r_scope_elem *[],
657 const struct r_found_version *,
658 int, int,
659 struct link_map *);
660 int (*_dl_check_caller) (const void *, enum allowmask);
661 void *(*_dl_open) (const char *file, int mode, const void *caller_dlopen,
662 Lmid_t nsid, int argc, char *argv[], char *env[]);
663 void (*_dl_close) (void *map);
665 /* List of auditing interfaces. */
666 struct audit_ifaces *_dl_audit;
667 unsigned int _dl_naudit;
669 # define __rtld_global_attribute__
670 # ifdef IS_IN_rtld
671 # ifdef HAVE_VISIBILITY_ATTRIBUTE
672 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
673 # else
674 # define __rtld_local_attribute__
675 # endif
676 extern struct rtld_global_ro _rtld_local_ro
677 attribute_relro __rtld_local_attribute__;
678 extern struct rtld_global_ro _rtld_global_ro
679 attribute_relro __rtld_global_attribute__;
680 # undef __rtld_local_attribute__
681 # else
682 /* We cheat a bit here. We declare the variable as as const even
683 though it is at startup. */
684 extern const struct rtld_global_ro _rtld_global_ro
685 attribute_relro __rtld_global_attribute__;
686 # endif
687 # undef __rtld_global_attribute__
688 #endif
689 #undef EXTERN
691 #ifdef IS_IN_rtld
692 /* This is the initial value of GL(dl_error_catch_tsd).
693 A non-TLS libpthread will change it. */
694 extern void **_dl_initial_error_catch_tsd (void) __attribute__ ((const))
695 attribute_hidden;
696 #endif
698 /* This is the initial value of GL(dl_make_stack_executable_hook).
699 A threads library can change it. */
700 extern int _dl_make_stack_executable (void **stack_endp) internal_function;
701 rtld_hidden_proto (_dl_make_stack_executable)
703 /* Variable pointing to the end of the stack (or close to it). This value
704 must be constant over the runtime of the application. Some programs
705 might use the variable which results in copy relocations on some
706 platforms. But this does not matter, ld.so can always use the local
707 copy. */
708 extern void *__libc_stack_end attribute_relro;
709 rtld_hidden_proto (__libc_stack_end)
711 /* Parameters passed to the dynamic linker. */
712 extern int _dl_argc attribute_hidden attribute_relro;
713 extern char **_dl_argv
714 #ifndef DL_ARGV_NOT_RELRO
715 attribute_relro
716 #endif
718 #ifdef IS_IN_rtld
719 extern char **_dl_argv_internal attribute_hidden
720 # ifndef DL_ARGV_NOT_RELRO
721 attribute_relro
722 # endif
724 # define rtld_progname (INTUSE(_dl_argv)[0])
725 #else
726 # define rtld_progname _dl_argv[0]
727 #endif
729 /* Flag set at startup and cleared when the last initializer has run. */
730 extern int _dl_starting_up;
731 weak_extern (_dl_starting_up)
732 #ifdef IS_IN_rtld
733 extern int _dl_starting_up_internal attribute_hidden;
734 #endif
736 /* OS-dependent function to open the zero-fill device. */
737 extern int _dl_sysdep_open_zero_fill (void); /* dl-sysdep.c */
740 /* Write message on the debug file descriptor. The parameters are
741 interpreted as for a `printf' call. All the lines start with a
742 tag showing the PID. */
743 extern void _dl_debug_printf (const char *fmt, ...)
744 __attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden;
746 /* Write message on the debug file descriptor. The parameters are
747 interpreted as for a `printf' call. All the lines buf the first
748 start with a tag showing the PID. */
749 extern void _dl_debug_printf_c (const char *fmt, ...)
750 __attribute__ ((__format__ (__printf__, 1, 2)));
753 /* Write a message on the specified descriptor FD. The parameters are
754 interpreted as for a `printf' call. */
755 extern void _dl_dprintf (int fd, const char *fmt, ...)
756 __attribute__ ((__format__ (__printf__, 2, 3)))
757 attribute_hidden;
759 /* Write a message on the specified descriptor standard output. The
760 parameters are interpreted as for a `printf' call. */
761 #define _dl_printf(fmt, args...) \
762 _dl_dprintf (STDOUT_FILENO, fmt, ##args)
764 /* Write a message on the specified descriptor standard error. The
765 parameters are interpreted as for a `printf' call. */
766 #define _dl_error_printf(fmt, args...) \
767 _dl_dprintf (STDERR_FILENO, fmt, ##args)
769 /* Write a message on the specified descriptor standard error and exit
770 the program. The parameters are interpreted as for a `printf' call. */
771 #define _dl_fatal_printf(fmt, args...) \
772 do \
774 _dl_dprintf (STDERR_FILENO, fmt, ##args); \
775 _exit (127); \
777 while (1)
780 /* This function is called by all the internal dynamic linker functions
781 when they encounter an error. ERRCODE is either an `errno' code or
782 zero; OBJECT is the name of the problematical shared object, or null if
783 it is a general problem; ERRSTRING is a string describing the specific
784 problem. */
785 extern void _dl_signal_error (int errcode, const char *object,
786 const char *occurred, const char *errstring)
787 internal_function __attribute__ ((__noreturn__)) attribute_hidden;
789 /* Like _dl_signal_error, but may return when called in the context of
790 _dl_receive_error. */
791 extern void _dl_signal_cerror (int errcode, const char *object,
792 const char *occation, const char *errstring)
793 internal_function;
795 /* Call OPERATE, receiving errors from `dl_signal_cerror'. Unlike
796 `_dl_catch_error' the operation is resumed after the OPERATE
797 function returns.
798 ARGS is passed as argument to OPERATE. */
799 extern void _dl_receive_error (receiver_fct fct, void (*operate) (void *),
800 void *args)
801 internal_function;
804 /* Open the shared object NAME and map in its segments.
805 LOADER's DT_RPATH is used in searching for NAME.
806 If the object is already opened, returns its existing map.
807 For preloaded shared objects PRELOADED is set to a non-zero
808 value to allow additional security checks. */
809 extern struct link_map *_dl_map_object (struct link_map *loader,
810 const char *name, int preloaded,
811 int type, int trace_mode, int mode,
812 Lmid_t nsid)
813 internal_function attribute_hidden;
815 /* Call _dl_map_object on the dependencies of MAP, and set up
816 MAP->l_searchlist. PRELOADS points to a vector of NPRELOADS previously
817 loaded objects that will be inserted into MAP->l_searchlist after MAP
818 but before its dependencies. */
819 extern void _dl_map_object_deps (struct link_map *map,
820 struct link_map **preloads,
821 unsigned int npreloads, int trace_mode,
822 int open_mode)
823 internal_function attribute_hidden;
825 /* Cache the locations of MAP's hash table. */
826 extern void _dl_setup_hash (struct link_map *map)
827 internal_function attribute_hidden;
830 /* Collect the directories in the search path for LOADER's dependencies.
831 The data structure is defined in <dlfcn.h>. If COUNTING is true,
832 SI->dls_cnt and SI->dls_size are set; if false, those must be as set
833 by a previous call with COUNTING set, and SI must point to SI->dls_size
834 bytes to be used in filling in the result. */
835 extern void _dl_rtld_di_serinfo (struct link_map *loader,
836 Dl_serinfo *si, bool counting)
837 internal_function;
840 /* Search loaded objects' symbol tables for a definition of the symbol
841 referred to by UNDEF. *SYM is the symbol table entry containing the
842 reference; it is replaced with the defining symbol, and the base load
843 address of the defining object is returned. SYMBOL_SCOPE is a
844 null-terminated list of object scopes to search; each object's
845 l_searchlist (i.e. the segment of the dependency tree starting at that
846 object) is searched in turn. REFERENCE_NAME should name the object
847 containing the reference; it is used in error messages.
848 TYPE_CLASS describes the type of symbol we are looking for. */
849 enum
851 /* If necessary add dependency between user and provider object. */
852 DL_LOOKUP_ADD_DEPENDENCY = 1,
853 /* Return most recent version instead of default version for
854 unversioned lookup. */
855 DL_LOOKUP_RETURN_NEWEST = 2
858 /* Lookup versioned symbol. */
859 extern lookup_t _dl_lookup_symbol_x (const char *undef,
860 struct link_map *undef_map,
861 const ElfW(Sym) **sym,
862 struct r_scope_elem *symbol_scope[],
863 const struct r_found_version *version,
864 int type_class, int explicit,
865 struct link_map *skip_map)
866 internal_function attribute_hidden;
869 /* Look up symbol NAME in MAP's scope and return its run-time address. */
870 extern ElfW(Addr) _dl_symbol_value (struct link_map *map, const char *name)
871 internal_function;
873 /* Allocate a `struct link_map' for a new object being loaded,
874 and enter it into the _dl_main_map list. */
875 extern struct link_map *_dl_new_object (char *realname, const char *libname,
876 int type, struct link_map *loader,
877 int mode, Lmid_t nsid)
878 internal_function attribute_hidden;
880 /* Relocate the given object (if it hasn't already been).
881 SCOPE is passed to _dl_lookup_symbol in symbol lookups.
882 If LAZY is nonzero, don't relocate its PLT. */
883 extern void _dl_relocate_object (struct link_map *map,
884 struct r_scope_elem *scope[],
885 int lazy, int consider_profiling)
886 attribute_hidden;
888 /* Protect PT_GNU_RELRO area. */
889 extern void _dl_protect_relro (struct link_map *map)
890 internal_function attribute_hidden;
892 /* Call _dl_signal_error with a message about an unhandled reloc type.
893 TYPE is the result of ELFW(R_TYPE) (r_info), i.e. an R_<CPU>_* value.
894 PLT is nonzero if this was a PLT reloc; it just affects the message. */
895 extern void _dl_reloc_bad_type (struct link_map *map,
896 unsigned int type, int plt)
897 internal_function __attribute__ ((__noreturn__));
899 /* Resolve conflicts if prelinking. */
900 extern void _dl_resolve_conflicts (struct link_map *l,
901 ElfW(Rela) *conflict,
902 ElfW(Rela) *conflictend);
904 /* Check the version dependencies of all objects available through
905 MAP. If VERBOSE print some more diagnostics. */
906 extern int _dl_check_all_versions (struct link_map *map, int verbose,
907 int trace_mode)
908 internal_function;
910 /* Check the version dependencies for MAP. If VERBOSE print some more
911 diagnostics. */
912 extern int _dl_check_map_versions (struct link_map *map, int verbose,
913 int trace_mode)
914 internal_function;
916 /* Initialize the object in SCOPE by calling the constructors with
917 ARGC, ARGV, and ENV as the parameters. */
918 extern void _dl_init (struct link_map *main_map, int argc, char **argv,
919 char **env) internal_function attribute_hidden;
921 /* Call the finalizer functions of all shared objects whose
922 initializer functions have completed. */
923 extern void _dl_fini (void) internal_function;
925 /* Sort array MAPS according to dependencies of the contained objects. */
926 extern void _dl_sort_fini (struct link_map *l, struct link_map **maps,
927 size_t nmaps, char *used, Lmid_t ns)
928 internal_function;
930 /* The dynamic linker calls this function before and having changing
931 any shared object mappings. The `r_state' member of `struct r_debug'
932 says what change is taking place. This function's address is
933 the value of the `r_brk' member. */
934 extern void _dl_debug_state (void);
935 rtld_hidden_proto (_dl_debug_state)
937 /* Initialize `struct r_debug' if it has not already been done. The
938 argument is the run-time load address of the dynamic linker, to be put
939 in the `r_ldbase' member. Returns the address of the structure. */
940 extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns)
941 internal_function;
943 /* Initialize the basic data structure for the search paths. */
944 extern void _dl_init_paths (const char *library_path) internal_function;
946 /* Gather the information needed to install the profiling tables and start
947 the timers. */
948 extern void _dl_start_profile (void) internal_function attribute_hidden;
950 /* The actual functions used to keep book on the calls. */
951 extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc);
952 extern void _dl_mcount_internal (ElfW(Addr) frompc, ElfW(Addr) selfpc)
953 attribute_hidden;
955 /* This function is simply a wrapper around the _dl_mcount function
956 which does not require a FROMPC parameter since this is the
957 calling function. */
958 extern void _dl_mcount_wrapper (void *selfpc);
960 /* Show the members of the auxiliary array passed up from the kernel. */
961 extern void _dl_show_auxv (void) internal_function;
963 /* Return all environment variables starting with `LD_', one after the
964 other. */
965 extern char *_dl_next_ld_env_entry (char ***position) internal_function;
967 /* Return an array with the names of the important hardware capabilities. */
968 extern const struct r_strlenpair *_dl_important_hwcaps (const char *platform,
969 size_t paltform_len,
970 size_t *sz,
971 size_t *max_capstrlen)
972 internal_function;
974 /* Look up NAME in ld.so.cache and return the file name stored there,
975 or null if none is found. */
976 extern const char *_dl_load_cache_lookup (const char *name)
977 internal_function;
979 /* If the system does not support MAP_COPY we cannot leave the file open
980 all the time since this would create problems when the file is replaced.
981 Therefore we provide this function to close the file and open it again
982 once needed. */
983 extern void _dl_unload_cache (void) attribute_hidden;
985 /* System-dependent function to read a file's whole contents in the
986 most convenient manner available. *SIZEP gets the size of the
987 file. On error MAP_FAILED is returned. */
988 extern void *_dl_sysdep_read_whole_file (const char *file, size_t *sizep,
989 int prot)
990 internal_function attribute_hidden;
992 /* System-specific function to do initial startup for the dynamic linker.
993 After this, file access calls and getenv must work. This is responsible
994 for setting __libc_enable_secure if we need to be secure (e.g. setuid),
995 and for setting _dl_argc and _dl_argv, and then calling _dl_main. */
996 extern ElfW(Addr) _dl_sysdep_start (void **start_argptr,
997 void (*dl_main) (const ElfW(Phdr) *phdr,
998 ElfW(Word) phnum,
999 ElfW(Addr) *user_entry))
1000 attribute_hidden;
1002 extern void _dl_sysdep_start_cleanup (void)
1003 internal_function attribute_hidden;
1006 /* Determine next available module ID. */
1007 extern size_t _dl_next_tls_modid (void) internal_function attribute_hidden;
1009 /* Calculate offset of the TLS blocks in the static TLS block. */
1010 extern void _dl_determine_tlsoffset (void) internal_function attribute_hidden;
1012 /* Set up the data structures for TLS, when they were not set up at startup.
1013 Returns nonzero on malloc failure.
1014 This is called from _dl_map_object_from_fd or by libpthread. */
1015 extern int _dl_tls_setup (void) internal_function;
1016 rtld_hidden_proto (_dl_tls_setup)
1018 /* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */
1019 extern void *_dl_allocate_tls (void *mem) internal_function;
1020 rtld_hidden_proto (_dl_allocate_tls)
1022 /* Get size and alignment requirements of the static TLS block. */
1023 extern void _dl_get_tls_static_info (size_t *sizep, size_t *alignp)
1024 internal_function;
1026 extern void _dl_allocate_static_tls (struct link_map *map)
1027 internal_function attribute_hidden;
1029 /* These are internal entry points to the two halves of _dl_allocate_tls,
1030 only used within rtld.c itself at startup time. */
1031 extern void *_dl_allocate_tls_storage (void)
1032 internal_function attribute_hidden;
1033 extern void *_dl_allocate_tls_init (void *) internal_function;
1034 rtld_hidden_proto (_dl_allocate_tls_init)
1036 /* Deallocate memory allocated with _dl_allocate_tls. */
1037 extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb) internal_function;
1038 rtld_hidden_proto (_dl_deallocate_tls)
1040 #if defined USE_TLS
1041 extern void _dl_nothread_init_static_tls (struct link_map *) attribute_hidden;
1042 #endif
1044 /* Find origin of the executable. */
1045 extern const char *_dl_get_origin (void) attribute_hidden;
1047 /* Count DSTs. */
1048 extern size_t _dl_dst_count (const char *name, int is_path) attribute_hidden;
1050 /* Substitute DST values. */
1051 extern char *_dl_dst_substitute (struct link_map *l, const char *name,
1052 char *result, int is_path) attribute_hidden;
1054 /* Check validity of the caller. */
1055 extern int _dl_check_caller (const void *caller, enum allowmask mask)
1056 attribute_hidden;
1058 /* Open the shared object NAME, relocate it, and run its initializer if it
1059 hasn't already been run. MODE is as for `dlopen' (see <dlfcn.h>). If
1060 the object is already opened, returns its existing map. */
1061 extern void *_dl_open (const char *name, int mode, const void *caller,
1062 Lmid_t nsid, int argc, char *argv[], char *env[])
1063 attribute_hidden;
1065 /* Add module to slot information data. */
1066 extern void _dl_add_to_slotinfo (struct link_map *l) attribute_hidden;
1068 /* Update slot information data for at least the generation of the
1069 module with the given index. */
1070 extern struct link_map *_dl_update_slotinfo (unsigned long int req_modid);
1072 /* Look up the module's TLS block as for __tls_get_addr,
1073 but never touch anything. Return null if it's not allocated yet. */
1074 extern void *_dl_tls_get_addr_soft (struct link_map *l) internal_function;
1077 __END_DECLS
1079 #endif /* ldsodefs.h */