/* Call the termination functions of loaded shared objects.
- Copyright (C) 1995,96,1998-2002,2004 Free Software Foundation, Inc.
+ Copyright (C) 1995-2024 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
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, write to the Free
- Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- 02111-1307 USA. */
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
-#include <alloca.h>
#include <assert.h>
#include <string.h>
#include <ldsodefs.h>
-
-
-/* Type of the constructor functions. */
-typedef void (*fini_t) (void);
-
+#include <elf-initfini.h>
void
-internal_function
_dl_fini (void)
{
/* Lots of fun ahead. We have to call the destructors for all still
using `dlopen' there are possibly several other modules with its
dependencies to be taken into account. Therefore we have to start
determining the order of the modules once again from the beginning. */
- unsigned int i;
- unsigned int nloaded;
- struct link_map *l;
- struct link_map **maps = NULL;
- size_t maps_size = 0;
-
- /* We First run the destructors of the main namespaces, then the
- other ones. The order should not matter since the namespace
- content is supposed to be independent. But we can have auditing
- code in a auxiliaty namespace and we want it to monitor the
- destructors. */
- for (Lmid_t cnt = 0; cnt < DL_NNS; ++cnt)
+
+ /* We run the destructors of the main namespaces last. As for the
+ other namespaces, we pick run the destructors in them in reverse
+ order of the namespace ID. */
+#ifdef SHARED
+ int do_audit = 0;
+ again:
+#endif
+ for (Lmid_t ns = GL(dl_nns) - 1; ns >= 0; --ns)
{
/* Protect against concurrent loads and unloads. */
__rtld_lock_lock_recursive (GL(dl_load_lock));
- nloaded = GL(dl_ns)[cnt]._ns_nloaded;
-
- /* XXX Could it be (in static binaries) that there is no object
- loaded? */
- assert (cnt != LM_ID_BASE || nloaded > 0);
-
- /* Now we can allocate an array to hold all the pointers and copy
- the pointers in. */
- if (maps_size < nloaded * sizeof (struct link_map *))
- {
- if (maps_size == 0)
- {
- maps_size = nloaded * sizeof (struct link_map *);
- maps = (struct link_map **) alloca (maps_size);
- }
- else
- maps = (struct link_map **)
- extend_alloca (maps, maps_size,
- nloaded * sizeof (struct link_map *));
- }
-
- for (l = GL(dl_ns)[cnt]._ns_loaded, i = 0; l != NULL; l = l->l_next)
- {
- assert (i < nloaded);
-
- /* Do not handle ld.so in secondary namespaces. */
- if (l == l->l_real)
- {
- maps[i++] = l;
-
- /* Bump l_opencount of all objects so that they are not
- dlclose()ed from underneath us. */
- ++l->l_opencount;
- }
- }
- assert (cnt != LM_ID_BASE || i == nloaded);
- assert (cnt == LM_ID_BASE || i == nloaded || i == nloaded - 1);
- unsigned int nmaps = i;
-
- if (nmaps != 0)
+ unsigned int nloaded = GL(dl_ns)[ns]._ns_nloaded;
+ /* No need to do anything for empty namespaces or those used for
+ auditing DSOs. */
+ if (nloaded == 0
+#ifdef SHARED
+ || GL(dl_ns)[ns]._ns_loaded->l_auditing != do_audit
+#endif
+ )
+ __rtld_lock_unlock_recursive (GL(dl_load_lock));
+ else
{
- /* Now we have to do the sorting. */
- l = GL(dl_ns)[cnt]._ns_loaded;
- if (cnt == LM_ID_BASE)
- /* The main executable always comes first. */
- l = l->l_next;
- for (; l != NULL; l = l->l_next)
+#ifdef SHARED
+ _dl_audit_activity_nsid (ns, LA_ACT_DELETE);
+#endif
+
+ /* Now we can allocate an array to hold all the pointers and
+ copy the pointers in. */
+ struct link_map *maps[nloaded];
+
+ unsigned int i;
+ struct link_map *l;
+ assert (nloaded != 0 || GL(dl_ns)[ns]._ns_loaded == NULL);
+ for (l = GL(dl_ns)[ns]._ns_loaded, i = 0; l != NULL; l = l->l_next)
+ /* Do not handle ld.so in secondary namespaces. */
+ if (l == l->l_real)
+ {
+ assert (i < nloaded);
+
+ maps[i] = l;
+ l->l_idx = i;
+ ++i;
+
+ /* Bump l_direct_opencount of all objects so that they
+ are not dlclose()ed from underneath us. */
+ ++l->l_direct_opencount;
+ }
+ assert (ns != LM_ID_BASE || i == nloaded);
+ assert (ns == LM_ID_BASE || i == nloaded || i == nloaded - 1);
+ unsigned int nmaps = i;
+
+ /* Now we have to do the sorting. We can skip looking for the
+ binary itself which is at the front of the search list for
+ the main namespace. */
+ _dl_sort_maps (maps, nmaps, (ns == LM_ID_BASE), true);
+
+ /* We do not rely on the linked list of loaded object anymore
+ from this point on. We have our own list here (maps). The
+ various members of this list cannot vanish since the open
+ count is too high and will be decremented in this loop. So
+ we release the lock so that some code which might be called
+ from a destructor can directly or indirectly access the
+ lock. */
+ __rtld_lock_unlock_recursive (GL(dl_load_lock));
+
+ /* 'maps' now contains the objects in the right order. Now
+ call the destructors. We have to process this array from
+ the front. */
+ for (i = 0; i < nmaps; ++i)
{
- unsigned int j;
- unsigned int k;
-
- /* Find the place in the 'maps' array. */
- for (j = 1; maps[j] != l; ++j)
- ;
+ struct link_map *l = maps[i];
- /* Find all object for which the current one is a dependency and
- move the found object (if necessary) in front. */
- for (k = j + 1; k < nmaps; ++k)
+ if (l->l_init_called)
{
- struct link_map **runp = maps[k]->l_initfini;
- if (runp != NULL)
- {
- while (*runp != NULL)
- if (*runp == l)
- {
- struct link_map *here = maps[k];
-
- /* Move it now. */
- memmove (&maps[j] + 1,
- &maps[j],
- (k - j) * sizeof (struct link_map *));
- maps[j++] = here;
-
- break;
- }
- else
- ++runp;
- }
-
- if (__builtin_expect (maps[k]->l_reldeps != NULL, 0))
- {
- unsigned int m = maps[k]->l_reldepsact;
- struct link_map **relmaps = maps[k]->l_reldeps;
-
- while (m-- > 0)
- {
- if (relmaps[m] == l)
- {
- struct link_map *here = maps[k];
-
- /* Move it now. */
- memmove (&maps[j] + 1,
- &maps[j],
- (k - j) * sizeof (struct link_map *));
- maps[j] = here;
-
- break;
- }
- }
- }
+ _dl_call_fini (l);
+#ifdef SHARED
+ /* Auditing checkpoint: another object closed. */
+ _dl_audit_objclose (l);
+#endif
}
- }
- }
-
- /* We do not rely on the linked list of loaded object anymore from
- this point on. We have our own list here (maps). The various
- members of this list cannot vanish since the open count is too
- high and will be decremented in this loop. So we release the
- lock so that some code which might be called from a destructor
- can directly or indirectly access the lock. */
- __rtld_lock_unlock_recursive (GL(dl_load_lock));
-
- /* 'maps' now contains the objects in the right order. Now call the
- destructors. We have to process this array from the front. */
- for (i = 0; i < nmaps; ++i)
- {
- l = maps[i];
- if (l->l_init_called)
- {
- /* Make sure nothing happens if we are called twice. */
- l->l_init_called = 0;
-
- /* Don't call the destructors for objects we are not
- supposed to. */
- if (l->l_name[0] == '\0' && l->l_type == lt_executable)
- continue;
-
- /* Is there a destructor function? */
- if (l->l_info[DT_FINI_ARRAY] == NULL
- && l->l_info[DT_FINI] == NULL)
- continue;
-
- /* 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",
- l->l_name[0] ? l->l_name : rtld_progname,
- cnt);
-
- /* 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)
- ((fini_t) DL_DT_FINI_ADDRESS (l, l->l_addr + l->l_info[DT_FINI]->d_un.d_ptr)) ();
+ /* Correct the previous increment. */
+ --l->l_direct_opencount;
}
- /* Correct the previous increment. */
- --l->l_opencount;
+#ifdef SHARED
+ _dl_audit_activity_nsid (ns, LA_ACT_CONSISTENT);
+#endif
}
}
- if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_STATISTICS, 0))
+#ifdef SHARED
+ if (! do_audit && GLRO(dl_naudit) > 0)
+ {
+ do_audit = 1;
+ goto again;
+ }
+
+ if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_STATISTICS))
_dl_debug_printf ("\nruntime linker statistics:\n"
" final number of relocations: %lu\n"
"final number of relocations from cache: %lu\n",
GL(dl_num_relocations),
GL(dl_num_cache_relocations));
+#endif
}
projects / thirdparty / glibc.git / blobdiff