1 /* Run-time dynamic linker data structures for loaded ELF shared objects.
2 Copyright (C) 1995-2021 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, see
17 <https://www.gnu.org/licenses/>. */
33 #include <fpu_control.h>
36 #include <dl-lookupcfg.h>
37 #include <dl-sysdep.h>
38 #include <libc-lock.h>
39 #include <hp-timing.h>
45 #define VERSYMIDX(sym) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (sym))
46 #define VALIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
47 + DT_EXTRANUM + DT_VALTAGIDX (tag))
48 #define ADDRIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
49 + DT_EXTRANUM + DT_VALNUM + DT_ADDRTAGIDX (tag))
51 /* Type of GNU hash which the machine uses. */
52 #ifndef ELF_MACHINE_GNU_HASH_ADDRIDX
53 # define ELF_MACHINE_GNU_HASH_ADDRIDX ADDRIDX (DT_GNU_HASH)
56 /* Calculate the index of a symbol in GNU hash. */
57 #ifndef ELF_MACHINE_HASH_SYMIDX
58 # define ELF_MACHINE_HASH_SYMIDX(map, hasharr) \
59 ((hasharr) - (map)->l_gnu_chain_zero)
62 /* Setup MIPS xhash. Defined only for MIPS. */
63 #ifndef ELF_MACHINE_XHASH_SETUP
64 # define ELF_MACHINE_XHASH_SETUP(hash32, symbias, map) \
65 ((void) (hash32), (void) (symbias), (void) (map))
68 /* We use this macro to refer to ELF types independent of the native wordsize.
69 `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'. */
70 #define ELFW(type) _ElfW (ELF, __ELF_NATIVE_CLASS, type)
72 /* All references to the value of l_info[DT_PLTGOT],
73 l_info[DT_STRTAB], l_info[DT_SYMTAB], l_info[DT_RELA],
74 l_info[DT_REL], l_info[DT_JMPREL], and l_info[VERSYMIDX (DT_VERSYM)]
75 have to be accessed via the D_PTR macro. The macro is needed since for
76 most architectures the entry is already relocated - but for some not
77 and we need to relocate at access time. */
78 #ifdef DL_RO_DYN_SECTION
79 # define D_PTR(map, i) ((map)->i->d_un.d_ptr + (map)->l_addr)
81 # define D_PTR(map, i) (map)->i->d_un.d_ptr
84 /* Result of the lookup functions and how to retrieve the base address. */
85 typedef struct link_map
*lookup_t
;
86 #define LOOKUP_VALUE(map) map
87 #define LOOKUP_VALUE_ADDRESS(map, set) ((set) || (map) ? (map)->l_addr : 0)
89 /* Calculate the address of symbol REF using the base address from map MAP,
90 if non-NULL. Don't check for NULL map if MAP_SET is TRUE. */
91 #define SYMBOL_ADDRESS(map, ref, map_set) \
93 : (__glibc_unlikely ((ref)->st_shndx == SHN_ABS) ? 0 \
94 : LOOKUP_VALUE_ADDRESS (map, map_set)) + (ref)->st_value)
96 /* Type of a constructor function, in DT_INIT, DT_INIT_ARRAY,
98 typedef void (*dl_init_t
) (int, char **, char **);
100 /* On some architectures a pointer to a function is not just a pointer
101 to the actual code of the function but rather an architecture
102 specific descriptor. */
103 #ifndef ELF_FUNCTION_PTR_IS_SPECIAL
104 # define DL_SYMBOL_ADDRESS(map, ref) \
105 (void *) SYMBOL_ADDRESS (map, ref, false)
106 # define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr))
107 # define DL_CALL_DT_INIT(map, start, argc, argv, env) \
108 ((dl_init_t) (start)) (argc, argv, env)
109 # define DL_CALL_DT_FINI(map, start) ((fini_t) (start)) ()
112 /* On some architectures dladdr can't use st_size of all symbols this way. */
113 #define DL_ADDR_SYM_MATCH(L, SYM, MATCHSYM, ADDR) \
114 ((ADDR) >= (L)->l_addr + (SYM)->st_value \
115 && ((((SYM)->st_shndx == SHN_UNDEF || (SYM)->st_size == 0) \
116 && (ADDR) == (L)->l_addr + (SYM)->st_value) \
117 || (ADDR) < (L)->l_addr + (SYM)->st_value + (SYM)->st_size) \
118 && ((MATCHSYM) == NULL || (MATCHSYM)->st_value < (SYM)->st_value))
120 /* According to the ELF gABI no STV_HIDDEN or STV_INTERNAL symbols are
121 expected to be present in dynamic symbol tables as they should have
122 been either removed or converted to STB_LOCAL binding by the static
123 linker. However some GNU binutils versions produce such symbols in
124 some cases. To prevent such symbols present in a buggy binary from
125 preempting global symbols we filter them out with this predicate. */
126 static __always_inline
bool
127 dl_symbol_visibility_binds_local_p (const ElfW(Sym
) *sym
)
129 return (ELFW(ST_VISIBILITY
) (sym
->st_other
) == STV_HIDDEN
130 || ELFW(ST_VISIBILITY
) (sym
->st_other
) == STV_INTERNAL
);
133 /* Unmap a loaded object, called by _dl_close (). */
134 #ifndef DL_UNMAP_IS_SPECIAL
135 # define DL_UNMAP(map) _dl_unmap_segments (map)
138 /* Reloc type classes as returned by elf_machine_type_class().
139 ELF_RTYPE_CLASS_PLT means this reloc should not be satisfied by
140 some PLT symbol, ELF_RTYPE_CLASS_COPY means this reloc should not be
141 satisfied by any symbol in the executable. Some architectures do
142 not support copy relocations. In this case we define the macro to
143 zero so that the code for handling them gets automatically optimized
144 out. ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA means address of protected
145 data defined in the shared library may be external, i.e., due to copy
147 #define ELF_RTYPE_CLASS_PLT 1
148 #ifndef DL_NO_COPY_RELOCS
149 # define ELF_RTYPE_CLASS_COPY 2
151 # define ELF_RTYPE_CLASS_COPY 0
153 /* If DL_EXTERN_PROTECTED_DATA is defined, address of protected data
154 defined in the shared library may be external, i.e., due to copy
156 #ifdef DL_EXTERN_PROTECTED_DATA
157 # define ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA 4
159 # define ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA 0
162 /* ELF uses the PF_x macros to specify the segment permissions, mmap
163 uses PROT_xxx. In most cases the three macros have the values 1, 2,
164 and 3 but not in a matching order. The following macros allows
165 converting from the PF_x values to PROT_xxx values. */
167 ((PROT_READ << (PF_R * 4)) \
168 | (PROT_WRITE << (PF_W * 4)) \
169 | (PROT_EXEC << (PF_X * 4)) \
170 | ((PROT_READ | PROT_WRITE) << ((PF_R | PF_W) * 4)) \
171 | ((PROT_READ | PROT_EXEC) << ((PF_R | PF_X) * 4)) \
172 | ((PROT_WRITE | PROT_EXEC) << (PF_W | PF_X) * 4) \
173 | ((PROT_READ | PROT_WRITE | PROT_EXEC) << ((PF_R | PF_W | PF_X) * 4)))
175 /* The filename itself, or the main program name, if available. */
176 #define DSO_FILENAME(name) ((name)[0] ? (name) \
177 : (rtld_progname ?: "<main program>"))
179 #define RTLD_PROGNAME (rtld_progname ?: "<program name unknown>")
181 /* For the version handling we need an array with only names and their
183 struct r_found_version
189 const char *filename
;
192 /* We want to cache information about the searches for shared objects. */
194 enum r_dir_status
{ unknown
, nonexisting
, existing
};
196 struct r_search_path_elem
198 /* This link is only used in the `all_dirs' member of `r_search_path'. */
199 struct r_search_path_elem
*next
;
201 /* Strings saying where the definition came from. */
205 /* Basename for this search path element. The string must end with
206 a slash character. */
210 enum r_dir_status status
[0];
220 /* A data structure for a simple single linked list of strings. */
223 const char *name
; /* Name requested (before search). */
224 struct libname_list
*next
; /* Link to next name for this object. */
225 int dont_free
; /* Flag whether this element should be freed
226 if the object is not entirely unloaded. */
230 /* Bit masks for the objects which valid callers can come from to
231 functions with restricted interface. */
236 allow_libpthread
= 4,
243 void (*activity
) (uintptr_t *, unsigned int);
244 char *(*objsearch
) (const char *, uintptr_t *, unsigned int);
245 unsigned int (*objopen
) (struct link_map
*, Lmid_t
, uintptr_t *);
246 void (*preinit
) (uintptr_t *);
249 uintptr_t (*symbind32
) (Elf32_Sym
*, unsigned int, uintptr_t *,
250 uintptr_t *, unsigned int *, const char *);
251 uintptr_t (*symbind64
) (Elf64_Sym
*, unsigned int, uintptr_t *,
252 uintptr_t *, unsigned int *, const char *);
256 #ifdef ARCH_PLTENTER_MEMBERS
257 ARCH_PLTENTER_MEMBERS
;
262 #ifdef ARCH_PLTEXIT_MEMBERS
263 ARCH_PLTEXIT_MEMBERS
;
266 unsigned int (*objclose
) (uintptr_t *);
268 struct audit_ifaces
*next
;
272 /* Test whether given NAME matches any of the names of the given object. */
273 extern int _dl_name_match_p (const char *__name
, const struct link_map
*__map
)
276 /* Compute next higher prime number. */
277 extern unsigned long int _dl_higher_prime_number (unsigned long int n
)
280 /* A stripped down strtoul-like implementation. */
281 uint64_t _dl_strtoul (const char *, char **) attribute_hidden
;
283 /* Function used as argument for `_dl_receive_error' function. The
284 arguments are the error code, error string, and the objname the
285 error occurred in. */
286 typedef void (*receiver_fct
) (int, const char *, const char *);
288 /* Internal functions of the run-time dynamic linker.
289 These can be accessed if you link again the dynamic linker
290 as a shared library, as in `-lld' or `/lib/ld.so' explicitly;
291 but are not normally of interest to user programs.
293 The `-ldl' library functions in <dlfcn.h> provide a simple
294 user interface to run-time dynamic linking. */
298 # define EXTERN extern
299 # define GL(name) _##name
303 # define GL(name) _rtld_local._##name
305 # define GL(name) _rtld_global._##name
310 /* Don't change the order of the following elements. 'dl_loaded'
311 must remain the first element. Forever. */
313 /* Non-shared code has no support for multiple namespaces. */
319 EXTERN
struct link_namespaces
321 /* A pointer to the map for the main map. */
322 struct link_map
*_ns_loaded
;
323 /* Number of object in the _dl_loaded list. */
324 unsigned int _ns_nloaded
;
325 /* Direct pointer to the searchlist of the main object. */
326 struct r_scope_elem
*_ns_main_searchlist
;
327 /* This is zero at program start to signal that the global scope map is
328 allocated by rtld. Later it keeps the size of the map. It might be
329 reset if in _dl_close if the last global object is removed. */
330 unsigned int _ns_global_scope_alloc
;
332 /* During dlopen, this is the number of objects that still need to
333 be added to the global scope map. It has to be taken into
334 account when resizing the map, for future map additions after
335 recursive dlopen calls from ELF constructors. */
336 unsigned int _ns_global_scope_pending_adds
;
338 /* Once libc.so has been loaded into the namespace, this points to
340 struct link_map
*libc_map
;
342 /* Search table for unique objects. */
343 struct unique_sym_table
345 __rtld_lock_define_recursive (, lock
)
350 const ElfW(Sym
) *sym
;
351 const struct link_map
*map
;
355 void (*free
) (void *);
356 } _ns_unique_sym_table
;
357 /* Keep track of changes to each namespace' list. */
358 struct r_debug _ns_debug
;
360 /* One higher than index of last used namespace. */
361 EXTERN
size_t _dl_nns
;
363 /* During the program run we must not modify the global data of
364 loaded shared object simultanously in two threads. Therefore we
365 protect `_dl_open' and `_dl_close' in dl-close.c.
367 This must be a recursive lock since the initializer function of
368 the loaded object might as well require a call to this function.
369 At this time it is not anymore a problem to modify the tables. */
370 __rtld_lock_define_recursive (EXTERN
, _dl_load_lock
)
371 /* This lock is used to keep __dl_iterate_phdr from inspecting the
372 list of loaded objects while an object is added to or removed
374 __rtld_lock_define_recursive (EXTERN
, _dl_load_write_lock
)
376 /* Incremented whenever something may have been added to dl_loaded. */
377 EXTERN
unsigned long long _dl_load_adds
;
379 /* The object to be initialized first. */
380 EXTERN
struct link_map
*_dl_initfirst
;
382 /* Map of shared object to be profiled. */
383 EXTERN
struct link_map
*_dl_profile_map
;
385 /* Counters for the number of relocations performed. */
386 EXTERN
unsigned long int _dl_num_relocations
;
387 EXTERN
unsigned long int _dl_num_cache_relocations
;
389 /* List of search directories. */
390 EXTERN
struct r_search_path_elem
*_dl_all_dirs
;
392 /* Structure describing the dynamic linker itself. */
393 EXTERN
struct link_map _dl_rtld_map
;
395 /* Used to store the audit information for the link map of the
397 struct auditstate _dl_rtld_auditstate
[DL_NNS
];
400 #if !PTHREAD_IN_LIBC && defined SHARED \
401 && defined __rtld_lock_default_lock_recursive
402 EXTERN
void (*_dl_rtld_lock_recursive
) (void *);
403 EXTERN
void (*_dl_rtld_unlock_recursive
) (void *);
406 /* Get architecture specific definitions. */
407 #define PROCINFO_DECL
408 #ifndef PROCINFO_CLASS
409 # define PROCINFO_CLASS EXTERN
411 #include <dl-procruntime.c>
414 /* If loading a shared object requires that we make the stack executable
415 when it was not, we do it by calling this function.
416 It returns an errno code or zero on success. */
417 EXTERN
int (*_dl_make_stack_executable_hook
) (void **);
420 /* Prevailing state of the stack, PF_X indicating it's executable. */
421 EXTERN
ElfW(Word
) _dl_stack_flags
;
423 /* Flag signalling whether there are gaps in the module ID allocation. */
424 EXTERN
bool _dl_tls_dtv_gaps
;
425 /* Highest dtv index currently needed. */
426 EXTERN
size_t _dl_tls_max_dtv_idx
;
427 /* Information about the dtv slots. */
428 EXTERN
struct dtv_slotinfo_list
431 struct dtv_slotinfo_list
*next
;
435 struct link_map
*map
;
437 } *_dl_tls_dtv_slotinfo_list
;
438 /* Number of modules in the static TLS block. */
439 EXTERN
size_t _dl_tls_static_nelem
;
440 /* Size actually allocated in the static TLS block. */
441 EXTERN
size_t _dl_tls_static_used
;
442 /* Remaining amount of static TLS that may be used for optimizing
443 dynamic TLS access (e.g. with TLSDESC). */
444 EXTERN
size_t _dl_tls_static_optional
;
446 /* Number of additional entries in the slotinfo array of each slotinfo
447 list element. A large number makes it almost certain take we never
448 have to iterate beyond the first element in the slotinfo list. */
449 #define TLS_SLOTINFO_SURPLUS (62)
451 /* Number of additional slots in the dtv allocated. */
452 #define DTV_SURPLUS (14)
454 /* Initial dtv of the main thread, not allocated with normal malloc. */
455 EXTERN
void *_dl_initial_dtv
;
456 /* Generation counter for the dtv. */
457 EXTERN
size_t _dl_tls_generation
;
460 EXTERN
void (*_dl_init_static_tls
) (struct link_map
*);
463 /* Scopes to free after next THREAD_GSCOPE_WAIT (). */
464 EXTERN
struct dl_scope_free_list
468 } *_dl_scope_free_list
;
470 /* List of active thread stacks, with memory managed by glibc. */
471 EXTERN list_t _dl_stack_used
;
473 /* List of thread stacks that were allocated by the application. */
474 EXTERN list_t _dl_stack_user
;
476 /* List of queued thread stacks. */
477 EXTERN list_t _dl_stack_cache
;
479 /* Total size of all stacks in the cache (sum over stackblock_size). */
480 EXTERN
size_t _dl_stack_cache_actsize
;
482 /* We need to record what list operations we are going to do so
483 that, in case of an asynchronous interruption due to a fork()
484 call, we can correct for the work. */
485 EXTERN
uintptr_t _dl_in_flight_stack
;
487 /* Mutex protecting the stack lists. */
488 EXTERN
int _dl_stack_cache_lock
;
490 #if !THREAD_GSCOPE_IN_TCB
491 EXTERN
int _dl_thread_gscope_count
;
495 # define __rtld_global_attribute__
497 # ifdef HAVE_SDATA_SECTION
498 # define __rtld_local_attribute__ \
499 __attribute__ ((visibility ("hidden"), section (".sdata")))
500 # undef __rtld_global_attribute__
501 # define __rtld_global_attribute__ __attribute__ ((section (".sdata")))
503 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
505 extern struct rtld_global _rtld_local __rtld_local_attribute__
;
506 # undef __rtld_local_attribute__
508 extern struct rtld_global _rtld_global __rtld_global_attribute__
;
509 # undef __rtld_global_attribute__
513 # define GLRO(name) _##name
516 # define GLRO(name) _rtld_local_ro._##name
518 # define GLRO(name) _rtld_global_ro._##name
520 struct rtld_global_ro
524 /* If nonzero the appropriate debug information is printed. */
525 EXTERN
int _dl_debug_mask
;
526 #define DL_DEBUG_LIBS (1 << 0)
527 #define DL_DEBUG_IMPCALLS (1 << 1)
528 #define DL_DEBUG_BINDINGS (1 << 2)
529 #define DL_DEBUG_SYMBOLS (1 << 3)
530 #define DL_DEBUG_VERSIONS (1 << 4)
531 #define DL_DEBUG_RELOC (1 << 5)
532 #define DL_DEBUG_FILES (1 << 6)
533 #define DL_DEBUG_STATISTICS (1 << 7)
534 #define DL_DEBUG_UNUSED (1 << 8)
535 #define DL_DEBUG_SCOPES (1 << 9)
536 /* These two are used only internally. */
537 #define DL_DEBUG_HELP (1 << 10)
538 #define DL_DEBUG_PRELINK (1 << 11)
541 EXTERN
unsigned int _dl_osversion
;
543 EXTERN
const char *_dl_platform
;
544 EXTERN
size_t _dl_platformlen
;
546 /* Cached value of `getpagesize ()'. */
547 EXTERN
size_t _dl_pagesize
;
549 /* Cached value of `sysconf (_SC_MINSIGSTKSZ)'. */
550 EXTERN
size_t _dl_minsigstacksize
;
552 /* Do we read from ld.so.cache? */
553 EXTERN
int _dl_inhibit_cache
;
555 /* Copy of the content of `_dl_main_searchlist' at startup time. */
556 EXTERN
struct r_scope_elem _dl_initial_searchlist
;
558 /* CLK_TCK as reported by the kernel. */
559 EXTERN
int _dl_clktck
;
561 /* If nonzero print warnings messages. */
562 EXTERN
int _dl_verbose
;
564 /* File descriptor to write debug messages to. */
565 EXTERN
int _dl_debug_fd
;
567 /* Do we do lazy relocations? */
570 /* Nonzero if runtime lookups should not update the .got/.plt. */
571 EXTERN
int _dl_bind_not
;
573 /* Nonzero if references should be treated as weak during runtime
575 EXTERN
int _dl_dynamic_weak
;
577 /* Default floating-point control word. */
578 EXTERN fpu_control_t _dl_fpu_control
;
580 /* Expected cache ID. */
581 EXTERN
int _dl_correct_cache_id
;
583 /* Mask for hardware capabilities that are available. */
584 EXTERN
uint64_t _dl_hwcap
;
587 /* Mask for important hardware capabilities we honour. */
588 EXTERN
uint64_t _dl_hwcap_mask
;
591 #ifdef HAVE_AUX_VECTOR
592 /* Pointer to the auxv list supplied to the program at startup. */
593 EXTERN
ElfW(auxv_t
) *_dl_auxv
;
596 /* Get architecture specific definitions. */
597 #include <dl-procinfo.c>
599 /* Names of shared object for which the RPATH should be ignored. */
600 EXTERN
const char *_dl_inhibit_rpath
;
602 /* Location of the binary. */
603 EXTERN
const char *_dl_origin_path
;
605 /* -1 if the dynamic linker should honor library load bias,
606 0 if not, -2 use the default (honor biases for normal
607 binaries, don't honor for PIEs). */
608 EXTERN
ElfW(Addr
) _dl_use_load_bias
;
610 /* Size of the static TLS block. */
611 EXTERN
size_t _dl_tls_static_size
;
613 /* Alignment requirement of the static TLS block. */
614 EXTERN
size_t _dl_tls_static_align
;
616 /* Size of surplus space in the static TLS area for dynamically
617 loaded modules with IE-model TLS or for TLSDESC optimization.
618 See comments in elf/dl-tls.c where it is initialized. */
619 EXTERN
size_t _dl_tls_static_surplus
;
621 /* Name of the shared object to be profiled (if any). */
622 EXTERN
const char *_dl_profile
;
623 /* Filename of the output file. */
624 EXTERN
const char *_dl_profile_output
;
625 /* Name of the object we want to trace the prelinking. */
626 EXTERN
const char *_dl_trace_prelink
;
627 /* Map of shared object to be prelink traced. */
628 EXTERN
struct link_map
*_dl_trace_prelink_map
;
630 /* All search directories defined at startup. This is assigned a
631 non-NULL pointer by the ld.so startup code (after initialization
632 to NULL), so this can also serve as an indicator whether a copy
633 of ld.so is initialized and active. See the rtld_active function
635 EXTERN
struct r_search_path_elem
*_dl_init_all_dirs
;
637 #ifdef NEED_DL_SYSINFO
638 /* Syscall handling improvements. This is very specific to x86. */
639 EXTERN
uintptr_t _dl_sysinfo
;
642 #ifdef 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
;
651 # define PROCINFO_DECL
652 # ifndef PROCINFO_CLASS
653 # define PROCINFO_CLASS EXTERN
655 # include <dl-vdso-setup.c>
658 /* Mask for more hardware capabilities that are available on some
660 EXTERN
uint64_t _dl_hwcap2
;
663 /* We add a function table to _rtld_global which is then used to
664 call the function instead of going through the PLT. The result
665 is that we can avoid exporting the functions and we do not jump
666 PLT relocations in libc.so. */
667 void (*_dl_debug_printf
) (const char *, ...)
668 __attribute__ ((__format__ (__printf__
, 1, 2)));
669 void (*_dl_mcount
) (ElfW(Addr
) frompc
, ElfW(Addr
) selfpc
);
670 lookup_t (*_dl_lookup_symbol_x
) (const char *, struct link_map
*,
671 const ElfW(Sym
) **, struct r_scope_elem
*[],
672 const struct r_found_version
*, int, int,
674 void *(*_dl_open
) (const char *file
, int mode
, const void *caller_dlopen
,
675 Lmid_t nsid
, int argc
, char *argv
[], char *env
[]);
676 void (*_dl_close
) (void *map
);
677 /* libdl in a secondary namespace (after dlopen) must use
678 _dl_catch_error from the main namespace, so it has to be
679 exported in some way. */
680 int (*_dl_catch_error
) (const char **objname
, const char **errstring
,
681 bool *mallocedp
, void (*operate
) (void *),
683 /* libdl in a secondary namespace must use free from the base
685 void (*_dl_error_free
) (void *);
686 void *(*_dl_tls_get_addr_soft
) (struct link_map
*);
687 #ifdef HAVE_DL_DISCOVER_OSVERSION
688 int (*_dl_discover_osversion
) (void);
691 /* Dynamic linker operations used after static dlopen. */
692 const struct dlfcn_hook
*_dl_dlfcn_hook
;
694 /* List of auditing interfaces. */
695 struct audit_ifaces
*_dl_audit
;
696 unsigned int _dl_naudit
;
698 # define __rtld_global_attribute__
700 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
701 extern struct rtld_global_ro _rtld_local_ro
702 attribute_relro __rtld_local_attribute__
;
703 extern struct rtld_global_ro _rtld_global_ro
704 attribute_relro __rtld_global_attribute__
;
705 # undef __rtld_local_attribute__
707 /* We cheat a bit here. We declare the variable as as const even
708 though it is at startup. */
709 extern const struct rtld_global_ro _rtld_global_ro
710 attribute_relro __rtld_global_attribute__
;
712 # undef __rtld_global_attribute__
717 /* dl-support.c defines these and initializes them early on. */
718 extern const ElfW(Phdr
) *_dl_phdr
;
719 extern size_t _dl_phnum
;
723 /* This function changes the permissions of all stacks (not just those
724 of the main stack). */
725 int _dl_make_stacks_executable (void **stack_endp
) attribute_hidden
;
727 /* This is the initial value of GL(dl_make_stack_executable_hook).
728 A threads library can change it. The ld.so implementation changes
729 the permissions of the main stack only. */
730 extern int _dl_make_stack_executable (void **stack_endp
);
731 rtld_hidden_proto (_dl_make_stack_executable
)
734 /* Variable pointing to the end of the stack (or close to it). This value
735 must be constant over the runtime of the application. Some programs
736 might use the variable which results in copy relocations on some
737 platforms. But this does not matter, ld.so can always use the local
739 extern void *__libc_stack_end
740 #ifndef LIBC_STACK_END_NOT_RELRO
744 rtld_hidden_proto (__libc_stack_end
)
746 /* Parameters passed to the dynamic linker. */
747 extern int _dl_argc attribute_hidden attribute_relro
;
748 extern char **_dl_argv
749 #ifndef DL_ARGV_NOT_RELRO
753 rtld_hidden_proto (_dl_argv
)
755 extern unsigned int _dl_skip_args attribute_hidden
756 # ifndef DL_ARGV_NOT_RELRO
760 extern unsigned int _dl_skip_args_internal attribute_hidden
761 # ifndef DL_ARGV_NOT_RELRO
766 #define rtld_progname _dl_argv[0]
768 /* Flag set at startup and cleared when the last initializer has run. */
769 extern int _dl_starting_up
;
770 weak_extern (_dl_starting_up
)
771 rtld_hidden_proto (_dl_starting_up
)
773 /* Random data provided by the kernel. */
774 extern void *_dl_random attribute_hidden attribute_relro
;
776 /* Write message on the debug file descriptor. The parameters are
777 interpreted as for a `printf' call. All the lines start with a
778 tag showing the PID. */
779 extern void _dl_debug_printf (const char *fmt
, ...)
780 __attribute__ ((__format__ (__printf__
, 1, 2))) attribute_hidden
;
782 /* Write message on the debug file descriptor. The parameters are
783 interpreted as for a `printf' call. All the lines buf the first
784 start with a tag showing the PID. */
785 extern void _dl_debug_printf_c (const char *fmt
, ...)
786 __attribute__ ((__format__ (__printf__
, 1, 2))) attribute_hidden
;
789 /* Write a message on the specified descriptor FD. The parameters are
790 interpreted as for a `printf' call. */
791 #if IS_IN (rtld) || !defined (SHARED)
792 extern void _dl_dprintf (int fd
, const char *fmt
, ...)
793 __attribute__ ((__format__ (__printf__
, 2, 3)))
796 __attribute__ ((always_inline
, __format__ (__printf__
, 2, 3)))
798 _dl_dprintf (int fd
, const char *fmt
, ...)
800 /* Use local declaration to avoid includign <stdio.h>. */
801 extern int __dprintf(int fd
, const char *format
, ...) attribute_hidden
;
802 __dprintf (fd
, fmt
, __builtin_va_arg_pack ());
806 /* Write LENGTH bytes at BUFFER to FD, like write. Returns the number
807 of bytes written on success, or a negative error constant on
809 ssize_t
_dl_write (int fd
, const void *buffer
, size_t length
)
812 /* Write a message on the specified descriptor standard output. The
813 parameters are interpreted as for a `printf' call. */
814 void _dl_printf (const char *fmt
, ...)
815 attribute_hidden
__attribute__ ((__format__ (__printf__
, 1, 2)));
817 /* Write a message on the specified descriptor standard error. The
818 parameters are interpreted as for a `printf' call. */
819 void _dl_error_printf (const char *fmt
, ...)
820 attribute_hidden
__attribute__ ((__format__ (__printf__
, 1, 2)));
822 /* Write a message on the specified descriptor standard error and exit
823 the program. The parameters are interpreted as for a `printf' call. */
824 void _dl_fatal_printf (const char *fmt
, ...)
825 __attribute__ ((__format__ (__printf__
, 1, 2), __noreturn__
));
826 rtld_hidden_proto (_dl_fatal_printf
)
828 /* An exception raised by the _dl_signal_error function family and
829 caught by _dl_catch_error function family. Exceptions themselves
830 are copied as part of the raise operation, but the strings are
835 const char *errstring
;
837 /* This buffer typically stores both objname and errstring
839 char *message_buffer
;
842 /* Creates a new exception. This calls malloc; if allocation fails,
843 dummy values are inserted. OBJECT is the name of the problematical
844 shared object, or null if its a general problem. ERRSTRING is a
845 string describing the specific problem. */
846 void _dl_exception_create (struct dl_exception
*, const char *object
,
847 const char *errstring
)
848 __attribute__ ((nonnull (1, 3)));
849 rtld_hidden_proto (_dl_exception_create
)
851 /* Used internally to implement dlerror message freeing. See
852 include/dlfcn.h and dlfcn/dlerror.c. */
853 void _dl_error_free (void *ptr
) attribute_hidden
;
855 /* Like _dl_exception_create, but create errstring from a format
856 string FMT. Currently, only "%s" and "%%" are supported as format
858 void _dl_exception_create_format (struct dl_exception
*, const char *objname
,
859 const char *fmt
, ...)
860 __attribute__ ((nonnull (1, 3), format (printf
, 3, 4)));
861 rtld_hidden_proto (_dl_exception_create_format
)
863 /* Deallocate the exception, freeing allocated buffers (if
865 void _dl_exception_free (struct dl_exception
*)
866 __attribute__ ((nonnull (1)));
867 rtld_hidden_proto (_dl_exception_free
)
869 /* This function is called by all the internal dynamic linker
870 functions when they encounter an error. ERRCODE is either an
871 `errno' code or zero; it specifies the return value of
872 _dl_catch_error. OCCASION is included in the error message if the
873 process is terminated immediately. */
874 void _dl_signal_exception (int errcode
, struct dl_exception
*,
875 const char *occasion
)
876 __attribute__ ((__noreturn__
));
877 libc_hidden_proto (_dl_signal_exception
)
879 /* Like _dl_signal_exception, but creates the exception first. */
880 extern void _dl_signal_error (int errcode
, const char *object
,
881 const char *occasion
, const char *errstring
)
882 __attribute__ ((__noreturn__
));
883 libc_hidden_proto (_dl_signal_error
)
885 /* Like _dl_signal_exception, but may return when called in the
886 context of _dl_receive_error. This is only used during ld.so
887 bootstrap. In static and profiled builds, this is equivalent to
888 _dl_signal_exception. */
890 extern void _dl_signal_cexception (int errcode
, struct dl_exception
*,
891 const char *occasion
) attribute_hidden
;
893 __attribute__ ((always_inline
))
895 _dl_signal_cexception (int errcode
, struct dl_exception
*exception
,
896 const char *occasion
)
898 _dl_signal_exception (errcode
, exception
, occasion
);
902 /* See _dl_signal_cexception above. */
904 extern void _dl_signal_cerror (int errcode
, const char *object
,
905 const char *occasion
, const char *errstring
)
908 __attribute__ ((always_inline
))
910 _dl_signal_cerror (int errcode
, const char *object
,
911 const char *occasion
, const char *errstring
)
913 _dl_signal_error (errcode
, object
, occasion
, errstring
);
917 /* Call OPERATE, receiving errors from `dl_signal_cerror'. Unlike
918 `_dl_catch_error' the operation is resumed after the OPERATE
920 ARGS is passed as argument to OPERATE. */
921 extern void _dl_receive_error (receiver_fct fct
, void (*operate
) (void *),
922 void *args
) attribute_hidden
;
924 /* Call OPERATE, catching errors from `_dl_signal_error' and related
925 functions. If there is no error, *ERRSTRING is set to null. If
926 there is an error, *ERRSTRING is set to a string constructed from
927 the strings passed to _dl_signal_error, and the error code passed
928 is the return value and *OBJNAME is set to the object name which
929 experienced the problems. ERRSTRING if nonzero points to a
930 malloc'ed string which the caller has to free after use. ARGS is
931 passed as argument to OPERATE. MALLOCEDP is set to true only if
932 the returned string is allocated using the libc's malloc. */
933 extern int _dl_catch_error (const char **objname
, const char **errstring
,
934 bool *mallocedp
, void (*operate
) (void *),
936 libc_hidden_proto (_dl_catch_error
)
938 /* Used for initializing GLRO (_dl_catch_error). */
939 extern __typeof__ (_dl_catch_error
) _rtld_catch_error attribute_hidden
;
941 /* Call OPERATE (ARGS). If no error occurs, set *EXCEPTION to zero.
942 Otherwise, store a copy of the raised exception in *EXCEPTION,
943 which has to be freed by _dl_exception_free. As a special case, if
944 EXCEPTION is null, call OPERATE (ARGS) with exception handling
945 disabled (so that exceptions are fatal). */
946 int _dl_catch_exception (struct dl_exception
*exception
,
947 void (*operate
) (void *), void *args
);
948 libc_hidden_proto (_dl_catch_exception
)
950 /* Open the shared object NAME and map in its segments.
951 LOADER's DT_RPATH is used in searching for NAME.
952 If the object is already opened, returns its existing map. */
953 extern struct link_map
*_dl_map_object (struct link_map
*loader
,
955 int type
, int trace_mode
, int mode
,
956 Lmid_t nsid
) attribute_hidden
;
958 /* Call _dl_map_object on the dependencies of MAP, and set up
959 MAP->l_searchlist. PRELOADS points to a vector of NPRELOADS previously
960 loaded objects that will be inserted into MAP->l_searchlist after MAP
961 but before its dependencies. */
962 extern void _dl_map_object_deps (struct link_map
*map
,
963 struct link_map
**preloads
,
964 unsigned int npreloads
, int trace_mode
,
968 /* Cache the locations of MAP's hash table. */
969 extern void _dl_setup_hash (struct link_map
*map
) attribute_hidden
;
972 /* Collect the directories in the search path for LOADER's dependencies.
973 The data structure is defined in <dlfcn.h>. If COUNTING is true,
974 SI->dls_cnt and SI->dls_size are set; if false, those must be as set
975 by a previous call with COUNTING set, and SI must point to SI->dls_size
976 bytes to be used in filling in the result. */
977 extern void _dl_rtld_di_serinfo (struct link_map
*loader
,
978 Dl_serinfo
*si
, bool counting
);
980 /* Process PT_GNU_PROPERTY program header PH in module L after
981 PT_LOAD segments are mapped from file FD. */
982 void _dl_process_pt_gnu_property (struct link_map
*l
, int fd
,
983 const ElfW(Phdr
) *ph
);
986 /* Search loaded objects' symbol tables for a definition of the symbol
987 referred to by UNDEF. *SYM is the symbol table entry containing the
988 reference; it is replaced with the defining symbol, and the base load
989 address of the defining object is returned. SYMBOL_SCOPE is a
990 null-terminated list of object scopes to search; each object's
991 l_searchlist (i.e. the segment of the dependency tree starting at that
992 object) is searched in turn. REFERENCE_NAME should name the object
993 containing the reference; it is used in error messages.
994 TYPE_CLASS describes the type of symbol we are looking for. */
997 /* If necessary add dependency between user and provider object. */
998 DL_LOOKUP_ADD_DEPENDENCY
= 1,
999 /* Return most recent version instead of default version for
1000 unversioned lookup. */
1001 DL_LOOKUP_RETURN_NEWEST
= 2,
1002 /* Set if dl_lookup* called with GSCOPE lock held. */
1003 DL_LOOKUP_GSCOPE_LOCK
= 4,
1004 /* Set if dl_lookup is called for non-lazy relocation processing
1005 from _dl_relocate_object in elf/dl-reloc.c. */
1006 DL_LOOKUP_FOR_RELOCATE
= 8,
1009 /* Lookup versioned symbol. */
1010 extern lookup_t
_dl_lookup_symbol_x (const char *undef
,
1011 struct link_map
*undef_map
,
1012 const ElfW(Sym
) **sym
,
1013 struct r_scope_elem
*symbol_scope
[],
1014 const struct r_found_version
*version
,
1015 int type_class
, int flags
,
1016 struct link_map
*skip_map
)
1020 /* Restricted version of _dl_lookup_symbol_x. Searches MAP (and only
1021 MAP) for the symbol UNDEF_NAME, with GNU hash NEW_HASH (computed
1022 with dl_new_hash), symbol version VERSION, and symbol version hash
1023 VERSION_HASH (computed with _dl_elf_hash). Returns a pointer to
1024 the symbol table entry in MAP on success, or NULL on failure. MAP
1025 must have symbol versioning information, or otherwise the result is
1027 const ElfW(Sym
) *_dl_lookup_direct (struct link_map
*map
,
1028 const char *undef_name
,
1030 const char *version
,
1031 uint32_t version_hash
) attribute_hidden
;
1033 /* Add the new link_map NEW to the end of the namespace list. */
1034 extern void _dl_add_to_namespace_list (struct link_map
*new, Lmid_t nsid
)
1037 /* Allocate a `struct link_map' for a new object being loaded. */
1038 extern struct link_map
*_dl_new_object (char *realname
, const char *libname
,
1039 int type
, struct link_map
*loader
,
1040 int mode
, Lmid_t nsid
)
1043 /* Relocate the given object (if it hasn't already been).
1044 SCOPE is passed to _dl_lookup_symbol in symbol lookups.
1045 If RTLD_LAZY is set in RELOC-MODE, don't relocate its PLT. */
1046 extern void _dl_relocate_object (struct link_map
*map
,
1047 struct r_scope_elem
*scope
[],
1048 int reloc_mode
, int consider_profiling
)
1051 /* Protect PT_GNU_RELRO area. */
1052 extern void _dl_protect_relro (struct link_map
*map
) attribute_hidden
;
1054 /* Call _dl_signal_error with a message about an unhandled reloc type.
1055 TYPE is the result of ELFW(R_TYPE) (r_info), i.e. an R_<CPU>_* value.
1056 PLT is nonzero if this was a PLT reloc; it just affects the message. */
1057 extern void _dl_reloc_bad_type (struct link_map
*map
,
1058 unsigned int type
, int plt
)
1059 attribute_hidden
__attribute__ ((__noreturn__
));
1061 /* Resolve conflicts if prelinking. */
1062 extern void _dl_resolve_conflicts (struct link_map
*l
,
1063 ElfW(Rela
) *conflict
,
1064 ElfW(Rela
) *conflictend
)
1067 /* Check the version dependencies of all objects available through
1068 MAP. If VERBOSE print some more diagnostics. */
1069 extern int _dl_check_all_versions (struct link_map
*map
, int verbose
,
1070 int trace_mode
) attribute_hidden
;
1072 /* Check the version dependencies for MAP. If VERBOSE print some more
1074 extern int _dl_check_map_versions (struct link_map
*map
, int verbose
,
1075 int trace_mode
) attribute_hidden
;
1077 /* Initialize the object in SCOPE by calling the constructors with
1078 ARGC, ARGV, and ENV as the parameters. */
1079 extern void _dl_init (struct link_map
*main_map
, int argc
, char **argv
,
1080 char **env
) attribute_hidden
;
1082 /* Call the finalizer functions of all shared objects whose
1083 initializer functions have completed. */
1084 extern void _dl_fini (void) attribute_hidden
;
1086 /* Sort array MAPS according to dependencies of the contained objects. */
1087 extern void _dl_sort_maps (struct link_map
**maps
, unsigned int nmaps
,
1088 char *used
, bool for_fini
) attribute_hidden
;
1090 /* The dynamic linker calls this function before and having changing
1091 any shared object mappings. The `r_state' member of `struct r_debug'
1092 says what change is taking place. This function's address is
1093 the value of the `r_brk' member. */
1094 extern void _dl_debug_state (void);
1095 rtld_hidden_proto (_dl_debug_state
)
1097 /* Initialize `struct r_debug' if it has not already been done. The
1098 argument is the run-time load address of the dynamic linker, to be put
1099 in the `r_ldbase' member. Returns the address of the structure. */
1100 extern struct r_debug
*_dl_debug_initialize (ElfW(Addr
) ldbase
, Lmid_t ns
)
1103 /* Initialize the basic data structure for the search paths. SOURCE
1104 is either "LD_LIBRARY_PATH" or "--library-path".
1105 GLIBC_HWCAPS_PREPEND adds additional glibc-hwcaps subdirectories to
1106 search. GLIBC_HWCAPS_MASK is used to filter the built-in
1107 subdirectories if not NULL. */
1108 extern void _dl_init_paths (const char *library_path
, const char *source
,
1109 const char *glibc_hwcaps_prepend
,
1110 const char *glibc_hwcaps_mask
)
1113 /* Gather the information needed to install the profiling tables and start
1115 extern void _dl_start_profile (void) attribute_hidden
;
1117 /* The actual functions used to keep book on the calls. */
1118 extern void _dl_mcount (ElfW(Addr
) frompc
, ElfW(Addr
) selfpc
);
1119 rtld_hidden_proto (_dl_mcount
)
1121 /* This function is simply a wrapper around the _dl_mcount function
1122 which does not require a FROMPC parameter since this is the
1123 calling function. */
1124 extern void _dl_mcount_wrapper (void *selfpc
);
1126 /* Show the members of the auxiliary array passed up from the kernel. */
1127 extern void _dl_show_auxv (void) attribute_hidden
;
1129 /* Return all environment variables starting with `LD_', one after the
1131 extern char *_dl_next_ld_env_entry (char ***position
) attribute_hidden
;
1133 /* Return an array with the names of the important hardware
1134 capabilities. PREPEND is a colon-separated list of glibc-hwcaps
1135 directories to search first. MASK is a colon-separated list used
1136 to filter the built-in glibc-hwcaps subdirectories. The length of
1137 the array is written to *SZ, and the maximum of all strings length
1138 is written to *MAX_CAPSTRLEN. */
1139 const struct r_strlenpair
*_dl_important_hwcaps (const char *prepend
,
1142 size_t *max_capstrlen
)
1145 /* Look up NAME in ld.so.cache and return the file name stored there,
1146 or null if none is found. Caller must free returned string. */
1147 extern char *_dl_load_cache_lookup (const char *name
) attribute_hidden
;
1149 /* If the system does not support MAP_COPY we cannot leave the file open
1150 all the time since this would create problems when the file is replaced.
1151 Therefore we provide this function to close the file and open it again
1153 extern void _dl_unload_cache (void) attribute_hidden
;
1155 /* System-dependent function to read a file's whole contents in the
1156 most convenient manner available. *SIZEP gets the size of the
1157 file. On error MAP_FAILED is returned. */
1158 extern void *_dl_sysdep_read_whole_file (const char *file
, size_t *sizep
,
1159 int prot
) attribute_hidden
;
1161 /* System-specific function to do initial startup for the dynamic linker.
1162 After this, file access calls and getenv must work. This is responsible
1163 for setting __libc_enable_secure if we need to be secure (e.g. setuid),
1164 and for setting _dl_argc and _dl_argv, and then calling _dl_main. */
1165 extern ElfW(Addr
) _dl_sysdep_start (void **start_argptr
,
1166 void (*dl_main
) (const ElfW(Phdr
) *phdr
,
1168 ElfW(Addr
) *user_entry
,
1169 ElfW(auxv_t
) *auxv
))
1172 extern void _dl_sysdep_start_cleanup (void) attribute_hidden
;
1175 /* Determine next available module ID and set the L l_tls_modid. */
1176 extern void _dl_assign_tls_modid (struct link_map
*l
) attribute_hidden
;
1178 /* Count the modules with TLS segments. */
1179 extern size_t _dl_count_modids (void) attribute_hidden
;
1181 /* Calculate offset of the TLS blocks in the static TLS block. */
1182 extern void _dl_determine_tlsoffset (void) attribute_hidden
;
1184 /* Calculate the size of the static TLS surplus, when the given
1185 number of audit modules are loaded. */
1186 void _dl_tls_static_surplus_init (size_t naudit
) attribute_hidden
;
1188 /* This function is called very early from dl_main to set up TLS and
1189 other thread-related data structures. */
1190 void __tls_pre_init_tp (void) attribute_hidden
;
1192 /* This function is called after processor-specific initialization of
1193 the TCB and thread pointer via TLS_INIT_TP, to complete very early
1194 initialization of the thread library. */
1195 void __tls_init_tp (void) attribute_hidden
;
1198 /* Set up the TCB for statically linked applications. This is called
1199 early during startup because we always use TLS (for errno and the
1200 stack protector, among other things). */
1201 void __libc_setup_tls (void);
1203 # if ENABLE_STATIC_PIE
1204 /* Relocate static executable with PIE. */
1205 extern void _dl_relocate_static_pie (void) attribute_hidden
;
1207 /* Get a pointer to _dl_main_map. */
1208 extern struct link_map
* _dl_get_dl_main_map (void)
1209 __attribute__ ((visibility ("hidden")));
1211 # define _dl_relocate_static_pie()
1215 /* Initialization of libpthread for statically linked applications.
1216 If libpthread is not linked in, this is an empty function. */
1217 void __pthread_initialize_minimal (void) weak_function
;
1219 /* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */
1220 extern void *_dl_allocate_tls (void *mem
);
1221 rtld_hidden_proto (_dl_allocate_tls
)
1223 /* Get size and alignment requirements of the static TLS block. */
1224 extern void _dl_get_tls_static_info (size_t *sizep
, size_t *alignp
);
1226 extern void _dl_allocate_static_tls (struct link_map
*map
) attribute_hidden
;
1228 /* These are internal entry points to the two halves of _dl_allocate_tls,
1229 only used within rtld.c itself at startup time. */
1230 extern void *_dl_allocate_tls_storage (void) attribute_hidden
;
1231 extern void *_dl_allocate_tls_init (void *);
1232 rtld_hidden_proto (_dl_allocate_tls_init
)
1234 /* Deallocate memory allocated with _dl_allocate_tls. */
1235 extern void _dl_deallocate_tls (void *tcb
, bool dealloc_tcb
);
1236 rtld_hidden_proto (_dl_deallocate_tls
)
1238 extern void _dl_nothread_init_static_tls (struct link_map
*) attribute_hidden
;
1240 /* Find origin of the executable. */
1241 extern const char *_dl_get_origin (void) attribute_hidden
;
1244 extern size_t _dl_dst_count (const char *name
) attribute_hidden
;
1246 /* Substitute DST values. */
1247 extern char *_dl_dst_substitute (struct link_map
*l
, const char *name
,
1248 char *result
) attribute_hidden
;
1250 /* Open the shared object NAME, relocate it, and run its initializer if it
1251 hasn't already been run. MODE is as for `dlopen' (see <dlfcn.h>). If
1252 the object is already opened, returns its existing map. */
1253 extern void *_dl_open (const char *name
, int mode
, const void *caller
,
1254 Lmid_t nsid
, int argc
, char *argv
[], char *env
[])
1257 /* Free or queue for freeing scope OLD. If other threads might be
1258 in the middle of _dl_fixup, _dl_profile_fixup or dl*sym using the
1259 old scope, OLD can't be freed until no thread is using it. */
1260 extern int _dl_scope_free (void *) attribute_hidden
;
1263 /* Add module to slot information data. If DO_ADD is false, only the
1264 required memory is allocated. Must be called with GL
1265 (dl_load_lock) acquired. If the function has already been called
1266 for the link map L with !do_add, then this function will not raise
1267 an exception, otherwise it is possible that it encounters a memory
1268 allocation failure. */
1269 extern void _dl_add_to_slotinfo (struct link_map
*l
, bool do_add
)
1272 /* Update slot information data for at least the generation of the
1273 module with the given index. */
1274 extern struct link_map
*_dl_update_slotinfo (unsigned long int req_modid
)
1277 /* Look up the module's TLS block as for __tls_get_addr,
1278 but never touch anything. Return null if it's not allocated yet. */
1279 extern void *_dl_tls_get_addr_soft (struct link_map
*l
) attribute_hidden
;
1281 extern int _dl_addr_inside_object (struct link_map
*l
, const ElfW(Addr
) addr
)
1284 /* Show show of an object. */
1285 extern void _dl_show_scope (struct link_map
*new, int from
)
1288 extern struct link_map
*_dl_find_dso_for_object (const ElfW(Addr
) addr
);
1289 rtld_hidden_proto (_dl_find_dso_for_object
)
1291 /* Initialization which is normally done by the dynamic linker. */
1292 extern void _dl_non_dynamic_init (void)
1295 /* Used by static binaries to check the auxiliary vector. */
1296 extern void _dl_aux_init (ElfW(auxv_t
) *av
)
1299 /* Initialize the static TLS space for the link map in all existing
1302 void _dl_init_static_tls (struct link_map
*map
) attribute_hidden
;
1305 dl_init_static_tls (struct link_map
*map
)
1308 /* The stack list is available to ld.so, so the initialization can
1309 be handled within ld.so directly. */
1310 _dl_init_static_tls (map
);
1312 GL (dl_init_static_tls
) (map
);
1317 /* Called before relocating ld.so during static dlopen. This can be
1318 used to partly initialize the dormant ld.so copy in the static
1319 dlopen namespace. */
1320 void __rtld_static_init (struct link_map
*map
) attribute_hidden
;
1323 /* Return true if the ld.so copy in this namespace is actually active
1324 and working. If false, the dl_open/dlfcn hooks have to be used to
1325 call into the outer dynamic linker (which happens after static
1331 /* The default-initialized variable does not have a non-zero
1332 dl_init_all_dirs member, so this allows us to recognize an
1333 initialized and active ld.so copy. */
1334 return GLRO(dl_init_all_dirs
) != NULL
;
1337 static inline struct auditstate
*
1338 link_map_audit_state (struct link_map
*l
, size_t index
)
1340 if (l
== &GL (dl_rtld_map
))
1341 /* The auditstate array is stored separately. */
1342 return &GL (dl_rtld_auditstate
) [index
];
1345 /* The auditstate array follows the link map in memory. */
1346 struct auditstate
*base
= (struct auditstate
*) (l
+ 1);
1347 return &base
[index
];
1352 #if PTHREAD_IN_LIBC && defined SHARED
1353 /* Recursive locking implementation for use within the dynamic loader.
1354 Used to define the __rtld_lock_lock_recursive and
1355 __rtld_lock_unlock_recursive via <libc-lock.h>. Initialized to a
1356 no-op dummy implementation early. Similar
1357 to GL (dl_rtld_lock_recursive) and GL (dl_rtld_unlock_recursive)
1358 in !PTHREAD_IN_LIBC builds. */
1359 extern int (*___rtld_mutex_lock
) (pthread_mutex_t
*) attribute_hidden
;
1360 extern int (*___rtld_mutex_unlock
) (pthread_mutex_t
*lock
) attribute_hidden
;
1362 /* Called after libc has been loaded, but before RELRO is activated.
1363 Used to initialize the function pointers to the actual
1365 void __rtld_mutex_init (void) attribute_hidden
;
1366 #else /* !PTHREAD_IN_LIBC */
1368 __rtld_mutex_init (void)
1370 /* The initialization happens later (!PTHREAD_IN_LIBC) or is not
1371 needed at all (!SHARED). */
1373 #endif /* !PTHREAD_IN_LIBC */
1375 #if THREAD_GSCOPE_IN_TCB
1376 void __thread_gscope_wait (void) attribute_hidden
;
1377 # define THREAD_GSCOPE_WAIT() __thread_gscope_wait ()
1382 #endif /* ldsodefs.h */