commit 6f360366f7f76b158a0f4bf20d42f2854ad56264 Author: Florian Weimer Date: Thu Oct 27 11:36:44 2022 +0200 elf: Introduce to _dl_call_fini This consolidates the destructor invocations from _dl_fini and dlclose. Remove the micro-optimization that avoids calling _dl_call_fini if they are no destructors (as dlclose is quite expensive anyway). The debug log message is now printed unconditionally. Reviewed-by: Adhemerval Zanella Conflicts: elf/dl-fini.c (Missing ELF_INITFINI support downstream.) sysdeps/generic/ldsodefs.h (Missing dl_init_t declaration downstream.) diff --git a/elf/Makefile b/elf/Makefile index 634c3113227d64a6..040d82e243a80c0f 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -50,6 +50,7 @@ routines = \ # profiled libraries. dl-routines = \ dl-call-libc-early-init \ + dl-call_fini \ dl-close \ dl-debug \ dl-deps \ diff --git a/elf/dl-call_fini.c b/elf/dl-call_fini.c new file mode 100644 index 0000000000000000..9e7ba10fa2a4df77 --- /dev/null +++ b/elf/dl-call_fini.c @@ -0,0 +1,50 @@ +/* Invoke DT_FINI and DT_FINI_ARRAY callbacks. + Copyright (C) 1996-2022 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include + +void +_dl_call_fini (void *closure_map) +{ + struct link_map *map = closure_map; + + /* When debugging print a message first. */ + if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_IMPCALLS)) + _dl_debug_printf ("\ncalling fini: %s [%lu]\n\n", map->l_name, map->l_ns); + + /* Make sure nothing happens if we are called twice. */ + map->l_init_called = 0; + + ElfW(Dyn) *fini_array = map->l_info[DT_FINI_ARRAY]; + if (fini_array != NULL) + { + ElfW(Addr) *array = (ElfW(Addr) *) (map->l_addr + + fini_array->d_un.d_ptr); + size_t sz = (map->l_info[DT_FINI_ARRAYSZ]->d_un.d_val + / sizeof (ElfW(Addr))); + + while (sz-- > 0) + ((fini_t) array[sz]) (); + } + + /* Next try the old-style destructor. */ + ElfW(Dyn) *fini = map->l_info[DT_FINI]; + if (fini != NULL) + DL_CALL_DT_FINI (map, ((void *) map->l_addr + fini->d_un.d_ptr)); +} diff --git a/elf/dl-close.c b/elf/dl-close.c index 22225efb3226c3e1..26ea51dfbadc5b85 100644 --- a/elf/dl-close.c +++ b/elf/dl-close.c @@ -35,11 +35,6 @@ #include - -/* Type of the constructor functions. */ -typedef void (*fini_t) (void); - - /* Special l_idx value used to indicate which objects remain loaded. */ #define IDX_STILL_USED -1 @@ -109,31 +104,6 @@ remove_slotinfo (size_t idx, struct dtv_slotinfo_list *listp, size_t disp, return false; } -/* Invoke dstructors for CLOSURE (a struct link_map *). Called with - exception handling temporarily disabled, to make errors fatal. */ -static void -call_destructors (void *closure) -{ - struct link_map *map = closure; - - if (map->l_info[DT_FINI_ARRAY] != NULL) - { - ElfW(Addr) *array = - (ElfW(Addr) *) (map->l_addr - + map->l_info[DT_FINI_ARRAY]->d_un.d_ptr); - unsigned int sz = (map->l_info[DT_FINI_ARRAYSZ]->d_un.d_val - / sizeof (ElfW(Addr))); - - while (sz-- > 0) - ((fini_t) array[sz]) (); - } - - /* Next try the old-style destructor. */ - if (map->l_info[DT_FINI] != NULL) - DL_CALL_DT_FINI (map, ((void *) map->l_addr - + map->l_info[DT_FINI]->d_un.d_ptr)); -} - void _dl_close_worker (struct link_map *map, bool force) { @@ -279,17 +249,7 @@ _dl_close_worker (struct link_map *map, bool force) half-cooked objects. Temporarily disable exception handling, so that errors are fatal. */ if (imap->l_init_called) - { - /* When debugging print a message first. */ - if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_IMPCALLS, - 0)) - _dl_debug_printf ("\ncalling fini: %s [%lu]\n\n", - imap->l_name, nsid); - - if (imap->l_info[DT_FINI_ARRAY] != NULL - || imap->l_info[DT_FINI] != NULL) - _dl_catch_exception (NULL, call_destructors, imap); - } + _dl_catch_exception (NULL, _dl_call_fini, imap); #ifdef SHARED /* Auditing checkpoint: we remove an object. */ diff --git a/elf/dl-fini.c b/elf/dl-fini.c index e14259a3c8806e0d..2d34658d4c3a470c 100644 --- a/elf/dl-fini.c +++ b/elf/dl-fini.c @@ -20,11 +20,6 @@ #include #include - -/* Type of the constructor functions. */ -typedef void (*fini_t) (void); - - void _dl_fini (void) { @@ -115,38 +110,7 @@ _dl_fini (void) if (l->l_init_called) { - /* Make sure nothing happens if we are called twice. */ - l->l_init_called = 0; - - /* Is there a destructor function? */ - if (l->l_info[DT_FINI_ARRAY] != NULL - || l->l_info[DT_FINI] != NULL) - { - /* When debugging print a message first. */ - if (__builtin_expect (GLRO(dl_debug_mask) - & DL_DEBUG_IMPCALLS, 0)) - _dl_debug_printf ("\ncalling fini: %s [%lu]\n\n", - DSO_FILENAME (l->l_name), - ns); - - /* First see whether an array is given. */ - if (l->l_info[DT_FINI_ARRAY] != NULL) - { - ElfW(Addr) *array = - (ElfW(Addr) *) (l->l_addr - + l->l_info[DT_FINI_ARRAY]->d_un.d_ptr); - unsigned int i = (l->l_info[DT_FINI_ARRAYSZ]->d_un.d_val - / sizeof (ElfW(Addr))); - while (i-- > 0) - ((fini_t) array[i]) (); - } - - /* Next try the old-style destructor. */ - if (l->l_info[DT_FINI] != NULL) - DL_CALL_DT_FINI - (l, l->l_addr + l->l_info[DT_FINI]->d_un.d_ptr); - } - + _dl_call_fini (l); #ifdef SHARED /* Auditing checkpoint: another object closed. */ _dl_audit_objclose (l); diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index 29bbde3e83e37d7e..0bad34d44a5685d9 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -93,6 +93,9 @@ typedef struct link_map *lookup_t; : (__glibc_unlikely ((ref)->st_shndx == SHN_ABS) ? 0 \ : LOOKUP_VALUE_ADDRESS (map, map_set)) + (ref)->st_value) +/* Type of a constructor function, in DT_FINI, DT_FINI_ARRAY. */ +typedef void (*fini_t) (void); + /* On some architectures a pointer to a function is not just a pointer to the actual code of the function but rather an architecture specific descriptor. */ @@ -1047,6 +1050,11 @@ extern void _dl_init (struct link_map *main_map, int argc, char **argv, initializer functions have completed. */ extern void _dl_fini (void) attribute_hidden; +/* Invoke the DT_FINI_ARRAY and DT_FINI destructors for MAP, which + must be a struct link_map *. Can be used as an argument to + _dl_catch_exception. */ +void _dl_call_fini (void *map) attribute_hidden; + /* Sort array MAPS according to dependencies of the contained objects. If FORCE_FIRST, MAPS[0] keeps its place even if the dependencies say otherwise. */