Fix compile error with sys/wait.h.
[glibc.git] / sysdeps / generic / ldsodefs.h
blobe18e60f73f1372f6c22fa9a423c5a6aef15d5ed3
1 /* Run-time dynamic linker data structures for loaded ELF shared objects.
2 Copyright (C) 1995-2006, 2007, 2008, 2009 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 <kernel-features.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 /* Compute next higher prime number. */
339 extern unsigned long int _dl_higher_prime_number (unsigned long int n)
340 internal_function;
342 /* Function used as argument for `_dl_receive_error' function. The
343 arguments are the error code, error string, and the objname the
344 error occurred in. */
345 typedef void (*receiver_fct) (int, const char *, const char *);
347 /* Internal functions of the run-time dynamic linker.
348 These can be accessed if you link again the dynamic linker
349 as a shared library, as in `-lld' or `/lib/ld.so' explicitly;
350 but are not normally of interest to user programs.
352 The `-ldl' library functions in <dlfcn.h> provide a simple
353 user interface to run-time dynamic linking. */
356 #ifndef SHARED
357 # define EXTERN extern
358 # define GL(name) _##name
359 #else
360 # define EXTERN
361 # ifdef IS_IN_rtld
362 # define GL(name) _rtld_local._##name
363 # else
364 # define GL(name) _rtld_global._##name
365 # endif
366 struct rtld_global
368 #endif
369 /* Don't change the order of the following elements. 'dl_loaded'
370 must remain the first element. Forever. */
372 /* Non-shared code has no support for multiple namespaces. */
373 #ifdef SHARED
374 # define DL_NNS 16
375 #else
376 # define DL_NNS 1
377 #endif
378 EXTERN struct link_namespaces
380 /* A pointer to the map for the main map. */
381 struct link_map *_ns_loaded;
382 /* Number of object in the _dl_loaded list. */
383 unsigned int _ns_nloaded;
384 /* Direct pointer to the searchlist of the main object. */
385 struct r_scope_elem *_ns_main_searchlist;
386 /* This is zero at program start to signal that the global scope map is
387 allocated by rtld. Later it keeps the size of the map. It might be
388 reset if in _dl_close if the last global object is removed. */
389 size_t _ns_global_scope_alloc;
390 /* Search table for unique objects. */
391 struct unique_sym_table
393 __rtld_lock_recursive_t lock;
394 struct unique_sym
396 uint32_t hashval;
397 const char *name;
398 const ElfW(Sym) *sym;
399 struct link_map *map;
400 } *entries;
401 size_t size;
402 size_t n_elements;
403 void (*free) (void *);
404 } _ns_unique_sym_table;
405 /* Keep track of changes to each namespace' list. */
406 struct r_debug _ns_debug;
407 } _dl_ns[DL_NNS];
408 /* One higher than index of last used namespace. */
409 EXTERN size_t _dl_nns;
411 /* During the program run we must not modify the global data of
412 loaded shared object simultanously in two threads. Therefore we
413 protect `_dl_open' and `_dl_close' in dl-close.c.
415 This must be a recursive lock since the initializer function of
416 the loaded object might as well require a call to this function.
417 At this time it is not anymore a problem to modify the tables. */
418 __rtld_lock_define_recursive (EXTERN, _dl_load_lock)
420 /* Incremented whenever something may have been added to dl_loaded. */
421 EXTERN unsigned long long _dl_load_adds;
423 /* The object to be initialized first. */
424 EXTERN struct link_map *_dl_initfirst;
426 #if HP_TIMING_AVAIL || HP_SMALL_TIMING_AVAIL
427 /* Start time on CPU clock. */
428 EXTERN hp_timing_t _dl_cpuclock_offset;
429 #endif
431 /* Map of shared object to be profiled. */
432 EXTERN struct link_map *_dl_profile_map;
434 /* Counters for the number of relocations performed. */
435 EXTERN unsigned long int _dl_num_relocations;
436 EXTERN unsigned long int _dl_num_cache_relocations;
438 /* List of search directories. */
439 EXTERN struct r_search_path_elem *_dl_all_dirs;
441 #ifdef _LIBC_REENTRANT
442 EXTERN void **(*_dl_error_catch_tsd) (void) __attribute__ ((const));
443 #endif
445 /* Structure describing the dynamic linker itself. We need to
446 reserve memory for the data the audit libraries need. */
447 EXTERN struct link_map _dl_rtld_map;
448 #ifdef SHARED
449 struct auditstate audit_data[DL_NNS];
450 #endif
452 #if defined SHARED && defined _LIBC_REENTRANT \
453 && defined __rtld_lock_default_lock_recursive
454 EXTERN void (*_dl_rtld_lock_recursive) (void *);
455 EXTERN void (*_dl_rtld_unlock_recursive) (void *);
456 #endif
458 /* If loading a shared object requires that we make the stack executable
459 when it was not, we do it by calling this function.
460 It returns an errno code or zero on success. */
461 EXTERN int (*_dl_make_stack_executable_hook) (void **) internal_function;
463 /* Prevailing state of the stack, PF_X indicating it's executable. */
464 EXTERN ElfW(Word) _dl_stack_flags;
466 /* Flag signalling whether there are gaps in the module ID allocation. */
467 EXTERN bool _dl_tls_dtv_gaps;
468 /* Highest dtv index currently needed. */
469 EXTERN size_t _dl_tls_max_dtv_idx;
470 /* Information about the dtv slots. */
471 EXTERN struct dtv_slotinfo_list
473 size_t len;
474 struct dtv_slotinfo_list *next;
475 struct dtv_slotinfo
477 size_t gen;
478 struct link_map *map;
479 } slotinfo[0];
480 } *_dl_tls_dtv_slotinfo_list;
481 /* Number of modules in the static TLS block. */
482 EXTERN size_t _dl_tls_static_nelem;
483 /* Size of the static TLS block. */
484 EXTERN size_t _dl_tls_static_size;
485 /* Size actually allocated in the static TLS block. */
486 EXTERN size_t _dl_tls_static_used;
487 /* Alignment requirement of the static TLS block. */
488 EXTERN size_t _dl_tls_static_align;
490 /* Number of additional entries in the slotinfo array of each slotinfo
491 list element. A large number makes it almost certain take we never
492 have to iterate beyond the first element in the slotinfo list. */
493 #define TLS_SLOTINFO_SURPLUS (62)
495 /* Number of additional slots in the dtv allocated. */
496 #define DTV_SURPLUS (14)
498 /* Initial dtv of the main thread, not allocated with normal malloc. */
499 EXTERN void *_dl_initial_dtv;
500 /* Generation counter for the dtv. */
501 EXTERN size_t _dl_tls_generation;
503 EXTERN void (*_dl_init_static_tls) (struct link_map *);
505 EXTERN void (*_dl_wait_lookup_done) (void);
507 /* Scopes to free after next THREAD_GSCOPE_WAIT (). */
508 EXTERN struct dl_scope_free_list
510 size_t count;
511 void *list[50];
512 } *_dl_scope_free_list;
513 #ifdef SHARED
515 # define __rtld_global_attribute__
516 # ifdef IS_IN_rtld
517 # ifdef HAVE_SDATA_SECTION
518 # define __rtld_local_attribute__ \
519 __attribute__ ((visibility ("hidden"), section (".sdata")))
520 # undef __rtld_global_attribute__
521 # define __rtld_global_attribute__ __attribute__ ((section (".sdata")))
522 # else
523 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
524 # endif
525 extern struct rtld_global _rtld_local __rtld_local_attribute__;
526 # undef __rtld_local_attribute__
527 # endif
528 extern struct rtld_global _rtld_global __rtld_global_attribute__;
529 # undef __rtld_global_attribute__
530 #endif
532 #ifndef SHARED
533 # define GLRO(name) _##name
534 #else
535 # ifdef IS_IN_rtld
536 # define GLRO(name) _rtld_local_ro._##name
537 # else
538 # define GLRO(name) _rtld_global_ro._##name
539 # endif
540 struct rtld_global_ro
542 #endif
544 /* If nonzero the appropriate debug information is printed. */
545 EXTERN int _dl_debug_mask;
546 #define DL_DEBUG_LIBS (1 << 0)
547 #define DL_DEBUG_IMPCALLS (1 << 1)
548 #define DL_DEBUG_BINDINGS (1 << 2)
549 #define DL_DEBUG_SYMBOLS (1 << 3)
550 #define DL_DEBUG_VERSIONS (1 << 4)
551 #define DL_DEBUG_RELOC (1 << 5)
552 #define DL_DEBUG_FILES (1 << 6)
553 #define DL_DEBUG_STATISTICS (1 << 7)
554 #define DL_DEBUG_UNUSED (1 << 8)
555 /* These two are used only internally. */
556 #define DL_DEBUG_HELP (1 << 9)
557 #define DL_DEBUG_PRELINK (1 << 10)
559 /* OS version. */
560 EXTERN unsigned int _dl_osversion;
561 /* Platform name. */
562 EXTERN const char *_dl_platform;
563 EXTERN size_t _dl_platformlen;
565 /* Cached value of `getpagesize ()'. */
566 EXTERN size_t _dl_pagesize;
568 /* Copy of the content of `_dl_main_searchlist' at startup time. */
569 EXTERN struct r_scope_elem _dl_initial_searchlist;
571 /* CLK_TCK as reported by the kernel. */
572 EXTERN int _dl_clktck;
574 /* If nonzero print warnings messages. */
575 EXTERN int _dl_verbose;
577 /* File descriptor to write debug messages to. */
578 EXTERN int _dl_debug_fd;
580 /* Do we do lazy relocations? */
581 EXTERN int _dl_lazy;
583 /* Nonzero if runtime lookups should not update the .got/.plt. */
584 EXTERN int _dl_bind_not;
586 /* Nonzero if references should be treated as weak during runtime
587 linking. */
588 EXTERN int _dl_dynamic_weak;
590 /* Default floating-point control word. */
591 EXTERN fpu_control_t _dl_fpu_control;
593 /* Expected cache ID. */
594 EXTERN int _dl_correct_cache_id;
596 /* Mask for hardware capabilities that are available. */
597 EXTERN uint64_t _dl_hwcap;
599 /* Mask for important hardware capabilities we honour. */
600 EXTERN uint64_t _dl_hwcap_mask;
602 /* Get architecture specific definitions. */
603 #define PROCINFO_DECL
604 #ifndef PROCINFO_CLASS
605 # define PROCINFO_CLASS EXTERN
606 #endif
607 #include <dl-procinfo.c>
609 /* Names of shared object for which the RPATH should be ignored. */
610 EXTERN const char *_dl_inhibit_rpath;
612 /* Location of the binary. */
613 EXTERN const char *_dl_origin_path;
615 /* -1 if the dynamic linker should honor library load bias,
616 0 if not, -2 use the default (honor biases for normal
617 binaries, don't honor for PIEs). */
618 EXTERN ElfW(Addr) _dl_use_load_bias;
620 /* Name of the shared object to be profiled (if any). */
621 EXTERN const char *_dl_profile;
622 /* Filename of the output file. */
623 EXTERN const char *_dl_profile_output;
624 /* Name of the object we want to trace the prelinking. */
625 EXTERN const char *_dl_trace_prelink;
626 /* Map of shared object to be prelink traced. */
627 EXTERN struct link_map *_dl_trace_prelink_map;
629 /* All search directories defined at startup. */
630 EXTERN struct r_search_path_elem *_dl_init_all_dirs;
632 #if HP_TIMING_AVAIL || HP_SMALL_TIMING_AVAIL
633 /* Overhead of a high-precision timing measurement. */
634 EXTERN hp_timing_t _dl_hp_timing_overhead;
635 #endif
637 #ifdef NEED_DL_SYSINFO
638 /* Syscall handling improvements. This is very specific to x86. */
639 EXTERN uintptr_t _dl_sysinfo;
640 #endif
642 #if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO
643 /* The vsyscall page is a virtual DSO pre-mapped by the kernel.
644 This points to its ELF header. */
645 EXTERN const ElfW(Ehdr) *_dl_sysinfo_dso;
647 /* At startup time we set up the normal DSO data structure for it,
648 and this points to it. */
649 EXTERN struct link_map *_dl_sysinfo_map;
650 #endif
652 #ifdef SHARED
653 /* We add a function table to _rtld_global which is then used to
654 call the function instead of going through the PLT. The result
655 is that we can avoid exporting the functions and we do not jump
656 PLT relocations in libc.so. */
657 void (*_dl_debug_printf) (const char *, ...)
658 __attribute__ ((__format__ (__printf__, 1, 2)));
659 int (internal_function *_dl_catch_error) (const char **, const char **,
660 bool *, void (*) (void *), void *);
661 void (internal_function *_dl_signal_error) (int, const char *, const char *,
662 const char *);
663 void (*_dl_mcount) (ElfW(Addr) frompc, ElfW(Addr) selfpc);
664 lookup_t (internal_function *_dl_lookup_symbol_x) (const char *,
665 struct link_map *,
666 const ElfW(Sym) **,
667 struct r_scope_elem *[],
668 const struct r_found_version *,
669 int, int,
670 struct link_map *);
671 int (*_dl_check_caller) (const void *, enum allowmask);
672 void *(*_dl_open) (const char *file, int mode, const void *caller_dlopen,
673 Lmid_t nsid, int argc, char *argv[], char *env[]);
674 void (*_dl_close) (void *map);
675 void *(*_dl_tls_get_addr_soft) (struct link_map *);
676 #ifdef HAVE_DL_DISCOVER_OSVERSION
677 int (*_dl_discover_osversion) (void);
678 #endif
680 /* List of auditing interfaces. */
681 struct audit_ifaces *_dl_audit;
682 unsigned int _dl_naudit;
684 /* 0 if internal pointer values should not be guarded, 1 if they should. */
685 EXTERN int _dl_pointer_guard;
687 # define __rtld_global_attribute__
688 # ifdef IS_IN_rtld
689 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
690 extern struct rtld_global_ro _rtld_local_ro
691 attribute_relro __rtld_local_attribute__;
692 extern struct rtld_global_ro _rtld_global_ro
693 attribute_relro __rtld_global_attribute__;
694 # undef __rtld_local_attribute__
695 # else
696 /* We cheat a bit here. We declare the variable as as const even
697 though it is at startup. */
698 extern const struct rtld_global_ro _rtld_global_ro
699 attribute_relro __rtld_global_attribute__;
700 # endif
701 # undef __rtld_global_attribute__
702 #endif
703 #undef EXTERN
705 #ifdef IS_IN_rtld
706 /* This is the initial value of GL(dl_error_catch_tsd).
707 A non-TLS libpthread will change it. */
708 extern void **_dl_initial_error_catch_tsd (void) __attribute__ ((const))
709 attribute_hidden;
710 #endif
712 /* This is the initial value of GL(dl_make_stack_executable_hook).
713 A threads library can change it. */
714 extern int _dl_make_stack_executable (void **stack_endp) internal_function;
715 rtld_hidden_proto (_dl_make_stack_executable)
717 /* Variable pointing to the end of the stack (or close to it). This value
718 must be constant over the runtime of the application. Some programs
719 might use the variable which results in copy relocations on some
720 platforms. But this does not matter, ld.so can always use the local
721 copy. */
722 extern void *__libc_stack_end attribute_relro;
723 rtld_hidden_proto (__libc_stack_end)
725 /* Parameters passed to the dynamic linker. */
726 extern int _dl_argc attribute_hidden attribute_relro;
727 extern char **_dl_argv
728 #ifndef DL_ARGV_NOT_RELRO
729 attribute_relro
730 #endif
732 #ifdef IS_IN_rtld
733 extern char **_dl_argv_internal attribute_hidden
734 # ifndef DL_ARGV_NOT_RELRO
735 attribute_relro
736 # endif
738 # define rtld_progname (INTUSE(_dl_argv)[0])
739 #else
740 # define rtld_progname _dl_argv[0]
741 #endif
743 /* Flag set at startup and cleared when the last initializer has run. */
744 extern int _dl_starting_up;
745 weak_extern (_dl_starting_up)
746 #ifdef IS_IN_rtld
747 extern int _dl_starting_up_internal attribute_hidden;
748 #endif
750 /* Random data provided by the kernel. */
751 extern void *_dl_random attribute_hidden;
753 /* OS-dependent function to open the zero-fill device. */
754 extern int _dl_sysdep_open_zero_fill (void); /* dl-sysdep.c */
757 /* Write message on the debug file descriptor. The parameters are
758 interpreted as for a `printf' call. All the lines start with a
759 tag showing the PID. */
760 extern void _dl_debug_printf (const char *fmt, ...)
761 __attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden;
763 /* Write message on the debug file descriptor. The parameters are
764 interpreted as for a `printf' call. All the lines buf the first
765 start with a tag showing the PID. */
766 extern void _dl_debug_printf_c (const char *fmt, ...)
767 __attribute__ ((__format__ (__printf__, 1, 2)));
770 /* Write a message on the specified descriptor FD. The parameters are
771 interpreted as for a `printf' call. */
772 extern void _dl_dprintf (int fd, const char *fmt, ...)
773 __attribute__ ((__format__ (__printf__, 2, 3)))
774 attribute_hidden;
776 /* Write a message on the specified descriptor standard output. The
777 parameters are interpreted as for a `printf' call. */
778 #define _dl_printf(fmt, args...) \
779 _dl_dprintf (STDOUT_FILENO, fmt, ##args)
781 /* Write a message on the specified descriptor standard error. The
782 parameters are interpreted as for a `printf' call. */
783 #define _dl_error_printf(fmt, args...) \
784 _dl_dprintf (STDERR_FILENO, fmt, ##args)
786 /* Write a message on the specified descriptor standard error and exit
787 the program. The parameters are interpreted as for a `printf' call. */
788 #define _dl_fatal_printf(fmt, args...) \
789 do \
791 _dl_dprintf (STDERR_FILENO, fmt, ##args); \
792 _exit (127); \
794 while (1)
797 /* This function is called by all the internal dynamic linker functions
798 when they encounter an error. ERRCODE is either an `errno' code or
799 zero; OBJECT is the name of the problematical shared object, or null if
800 it is a general problem; ERRSTRING is a string describing the specific
801 problem. */
802 extern void _dl_signal_error (int errcode, const char *object,
803 const char *occurred, const char *errstring)
804 internal_function __attribute__ ((__noreturn__)) attribute_hidden;
806 /* Like _dl_signal_error, but may return when called in the context of
807 _dl_receive_error. */
808 extern void _dl_signal_cerror (int errcode, const char *object,
809 const char *occation, const char *errstring)
810 internal_function;
812 /* Call OPERATE, receiving errors from `dl_signal_cerror'. Unlike
813 `_dl_catch_error' the operation is resumed after the OPERATE
814 function returns.
815 ARGS is passed as argument to OPERATE. */
816 extern void _dl_receive_error (receiver_fct fct, void (*operate) (void *),
817 void *args)
818 internal_function;
821 /* Open the shared object NAME and map in its segments.
822 LOADER's DT_RPATH is used in searching for NAME.
823 If the object is already opened, returns its existing map.
824 For preloaded shared objects PRELOADED is set to a non-zero
825 value to allow additional security checks. */
826 extern struct link_map *_dl_map_object (struct link_map *loader,
827 const char *name, int preloaded,
828 int type, int trace_mode, int mode,
829 Lmid_t nsid)
830 internal_function attribute_hidden;
832 /* Call _dl_map_object on the dependencies of MAP, and set up
833 MAP->l_searchlist. PRELOADS points to a vector of NPRELOADS previously
834 loaded objects that will be inserted into MAP->l_searchlist after MAP
835 but before its dependencies. */
836 extern void _dl_map_object_deps (struct link_map *map,
837 struct link_map **preloads,
838 unsigned int npreloads, int trace_mode,
839 int open_mode)
840 internal_function attribute_hidden;
842 /* Cache the locations of MAP's hash table. */
843 extern void _dl_setup_hash (struct link_map *map)
844 internal_function attribute_hidden;
847 /* Collect the directories in the search path for LOADER's dependencies.
848 The data structure is defined in <dlfcn.h>. If COUNTING is true,
849 SI->dls_cnt and SI->dls_size are set; if false, those must be as set
850 by a previous call with COUNTING set, and SI must point to SI->dls_size
851 bytes to be used in filling in the result. */
852 extern void _dl_rtld_di_serinfo (struct link_map *loader,
853 Dl_serinfo *si, bool counting)
854 internal_function;
857 /* Search loaded objects' symbol tables for a definition of the symbol
858 referred to by UNDEF. *SYM is the symbol table entry containing the
859 reference; it is replaced with the defining symbol, and the base load
860 address of the defining object is returned. SYMBOL_SCOPE is a
861 null-terminated list of object scopes to search; each object's
862 l_searchlist (i.e. the segment of the dependency tree starting at that
863 object) is searched in turn. REFERENCE_NAME should name the object
864 containing the reference; it is used in error messages.
865 TYPE_CLASS describes the type of symbol we are looking for. */
866 enum
868 /* If necessary add dependency between user and provider object. */
869 DL_LOOKUP_ADD_DEPENDENCY = 1,
870 /* Return most recent version instead of default version for
871 unversioned lookup. */
872 DL_LOOKUP_RETURN_NEWEST = 2,
873 /* Set if dl_lookup* called with GSCOPE lock held. */
874 DL_LOOKUP_GSCOPE_LOCK = 4,
877 /* Lookup versioned symbol. */
878 extern lookup_t _dl_lookup_symbol_x (const char *undef,
879 struct link_map *undef_map,
880 const ElfW(Sym) **sym,
881 struct r_scope_elem *symbol_scope[],
882 const struct r_found_version *version,
883 int type_class, int flags,
884 struct link_map *skip_map)
885 internal_function attribute_hidden;
888 /* Look up symbol NAME in MAP's scope and return its run-time address. */
889 extern ElfW(Addr) _dl_symbol_value (struct link_map *map, const char *name)
890 internal_function;
892 /* Allocate a `struct link_map' for a new object being loaded,
893 and enter it into the _dl_main_map list. */
894 extern struct link_map *_dl_new_object (char *realname, const char *libname,
895 int type, struct link_map *loader,
896 int mode, Lmid_t nsid)
897 internal_function attribute_hidden;
899 /* Relocate the given object (if it hasn't already been).
900 SCOPE is passed to _dl_lookup_symbol in symbol lookups.
901 If RTLD_LAZY is set in RELOC-MODE, don't relocate its PLT. */
902 extern void _dl_relocate_object (struct link_map *map,
903 struct r_scope_elem *scope[],
904 int reloc_mode, int consider_profiling)
905 attribute_hidden;
907 /* Protect PT_GNU_RELRO area. */
908 extern void _dl_protect_relro (struct link_map *map)
909 internal_function attribute_hidden;
911 /* Call _dl_signal_error with a message about an unhandled reloc type.
912 TYPE is the result of ELFW(R_TYPE) (r_info), i.e. an R_<CPU>_* value.
913 PLT is nonzero if this was a PLT reloc; it just affects the message. */
914 extern void _dl_reloc_bad_type (struct link_map *map,
915 unsigned int type, int plt)
916 internal_function __attribute__ ((__noreturn__));
918 /* Resolve conflicts if prelinking. */
919 extern void _dl_resolve_conflicts (struct link_map *l,
920 ElfW(Rela) *conflict,
921 ElfW(Rela) *conflictend);
923 /* Check the version dependencies of all objects available through
924 MAP. If VERBOSE print some more diagnostics. */
925 extern int _dl_check_all_versions (struct link_map *map, int verbose,
926 int trace_mode)
927 internal_function;
929 /* Check the version dependencies for MAP. If VERBOSE print some more
930 diagnostics. */
931 extern int _dl_check_map_versions (struct link_map *map, int verbose,
932 int trace_mode)
933 internal_function;
935 /* Initialize the object in SCOPE by calling the constructors with
936 ARGC, ARGV, and ENV as the parameters. */
937 extern void _dl_init (struct link_map *main_map, int argc, char **argv,
938 char **env) internal_function attribute_hidden;
940 /* Call the finalizer functions of all shared objects whose
941 initializer functions have completed. */
942 extern void _dl_fini (void) internal_function;
944 /* Sort array MAPS according to dependencies of the contained objects. */
945 extern void _dl_sort_fini (struct link_map *l, struct link_map **maps,
946 size_t nmaps, char *used, Lmid_t ns)
947 internal_function;
949 /* The dynamic linker calls this function before and having changing
950 any shared object mappings. The `r_state' member of `struct r_debug'
951 says what change is taking place. This function's address is
952 the value of the `r_brk' member. */
953 extern void _dl_debug_state (void);
954 rtld_hidden_proto (_dl_debug_state)
956 /* Initialize `struct r_debug' if it has not already been done. The
957 argument is the run-time load address of the dynamic linker, to be put
958 in the `r_ldbase' member. Returns the address of the structure. */
959 extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns)
960 internal_function;
962 /* Initialize the basic data structure for the search paths. */
963 extern void _dl_init_paths (const char *library_path) internal_function;
965 /* Gather the information needed to install the profiling tables and start
966 the timers. */
967 extern void _dl_start_profile (void) internal_function attribute_hidden;
969 /* The actual functions used to keep book on the calls. */
970 extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc);
971 extern void _dl_mcount_internal (ElfW(Addr) frompc, ElfW(Addr) selfpc)
972 attribute_hidden;
974 /* This function is simply a wrapper around the _dl_mcount function
975 which does not require a FROMPC parameter since this is the
976 calling function. */
977 extern void _dl_mcount_wrapper (void *selfpc);
979 /* Show the members of the auxiliary array passed up from the kernel. */
980 extern void _dl_show_auxv (void) internal_function;
982 /* Return all environment variables starting with `LD_', one after the
983 other. */
984 extern char *_dl_next_ld_env_entry (char ***position) internal_function;
986 /* Return an array with the names of the important hardware capabilities. */
987 extern const struct r_strlenpair *_dl_important_hwcaps (const char *platform,
988 size_t paltform_len,
989 size_t *sz,
990 size_t *max_capstrlen)
991 internal_function;
993 /* Look up NAME in ld.so.cache and return the file name stored there,
994 or null if none is found. */
995 extern const char *_dl_load_cache_lookup (const char *name)
996 internal_function;
998 /* If the system does not support MAP_COPY we cannot leave the file open
999 all the time since this would create problems when the file is replaced.
1000 Therefore we provide this function to close the file and open it again
1001 once needed. */
1002 extern void _dl_unload_cache (void) attribute_hidden;
1004 /* System-dependent function to read a file's whole contents in the
1005 most convenient manner available. *SIZEP gets the size of the
1006 file. On error MAP_FAILED is returned. */
1007 extern void *_dl_sysdep_read_whole_file (const char *file, size_t *sizep,
1008 int prot)
1009 internal_function attribute_hidden;
1011 /* System-specific function to do initial startup for the dynamic linker.
1012 After this, file access calls and getenv must work. This is responsible
1013 for setting __libc_enable_secure if we need to be secure (e.g. setuid),
1014 and for setting _dl_argc and _dl_argv, and then calling _dl_main. */
1015 extern ElfW(Addr) _dl_sysdep_start (void **start_argptr,
1016 void (*dl_main) (const ElfW(Phdr) *phdr,
1017 ElfW(Word) phnum,
1018 ElfW(Addr) *user_entry))
1019 attribute_hidden;
1021 extern void _dl_sysdep_start_cleanup (void)
1022 internal_function attribute_hidden;
1025 /* Determine next available module ID. */
1026 extern size_t _dl_next_tls_modid (void) internal_function attribute_hidden;
1028 /* Calculate offset of the TLS blocks in the static TLS block. */
1029 extern void _dl_determine_tlsoffset (void) internal_function attribute_hidden;
1031 /* Set up the data structures for TLS, when they were not set up at startup.
1032 Returns nonzero on malloc failure.
1033 This is called from _dl_map_object_from_fd or by libpthread. */
1034 extern int _dl_tls_setup (void) internal_function;
1035 rtld_hidden_proto (_dl_tls_setup)
1037 /* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */
1038 extern void *_dl_allocate_tls (void *mem) internal_function;
1039 rtld_hidden_proto (_dl_allocate_tls)
1041 /* Get size and alignment requirements of the static TLS block. */
1042 extern void _dl_get_tls_static_info (size_t *sizep, size_t *alignp)
1043 internal_function;
1045 extern void _dl_allocate_static_tls (struct link_map *map)
1046 internal_function attribute_hidden;
1048 /* These are internal entry points to the two halves of _dl_allocate_tls,
1049 only used within rtld.c itself at startup time. */
1050 extern void *_dl_allocate_tls_storage (void)
1051 internal_function attribute_hidden;
1052 extern void *_dl_allocate_tls_init (void *) internal_function;
1053 rtld_hidden_proto (_dl_allocate_tls_init)
1055 /* Deallocate memory allocated with _dl_allocate_tls. */
1056 extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb) internal_function;
1057 rtld_hidden_proto (_dl_deallocate_tls)
1059 extern void _dl_nothread_init_static_tls (struct link_map *) attribute_hidden;
1061 /* Find origin of the executable. */
1062 extern const char *_dl_get_origin (void) attribute_hidden;
1064 /* Count DSTs. */
1065 extern size_t _dl_dst_count (const char *name, int is_path) attribute_hidden;
1067 /* Substitute DST values. */
1068 extern char *_dl_dst_substitute (struct link_map *l, const char *name,
1069 char *result, int is_path) attribute_hidden;
1071 /* Check validity of the caller. */
1072 extern int _dl_check_caller (const void *caller, enum allowmask mask)
1073 attribute_hidden;
1075 /* Open the shared object NAME, relocate it, and run its initializer if it
1076 hasn't already been run. MODE is as for `dlopen' (see <dlfcn.h>). If
1077 the object is already opened, returns its existing map. */
1078 extern void *_dl_open (const char *name, int mode, const void *caller,
1079 Lmid_t nsid, int argc, char *argv[], char *env[])
1080 attribute_hidden;
1082 /* Free or queue for freeing scope OLD. If other threads might be
1083 in the middle of _dl_fixup, _dl_profile_fixup or dl*sym using the
1084 old scope, OLD can't be freed until no thread is using it. */
1085 extern int _dl_scope_free (void *) attribute_hidden;
1087 /* Add module to slot information data. */
1088 extern void _dl_add_to_slotinfo (struct link_map *l) attribute_hidden;
1090 /* Update slot information data for at least the generation of the
1091 module with the given index. */
1092 extern struct link_map *_dl_update_slotinfo (unsigned long int req_modid);
1094 /* Look up the module's TLS block as for __tls_get_addr,
1095 but never touch anything. Return null if it's not allocated yet. */
1096 extern void *_dl_tls_get_addr_soft (struct link_map *l) attribute_hidden;
1098 extern int _dl_addr_inside_object (struct link_map *l, const ElfW(Addr) addr)
1099 internal_function attribute_hidden;
1101 __END_DECLS
1103 #endif /* ldsodefs.h */