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authorUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
committerUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
commita334319f6530564d22e775935d9c91663623a1b4 (patch)
treeb5877475619e4c938e98757d518bb1e9cbead751 /elf/dl-lookup.c
parent0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (diff)
downloadglibc-a334319f6530564d22e775935d9c91663623a1b4.tar.gz
(CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.
Diffstat (limited to 'elf/dl-lookup.c')
-rw-r--r--elf/dl-lookup.c115
1 files changed, 48 insertions, 67 deletions
diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c
index e971929d0e..fdb076951d 100644
--- a/elf/dl-lookup.c
+++ b/elf/dl-lookup.c
@@ -1,5 +1,5 @@
/* Look up a symbol in the loaded objects.
- Copyright (C) 1995-2005, 2006, 2007 Free Software Foundation, Inc.
+ Copyright (C) 1995-2002, 2003, 2004 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
@@ -23,9 +23,8 @@
#include <string.h>
#include <unistd.h>
#include <ldsodefs.h>
-#include <dl-hash.h>
+#include "dl-hash.h"
#include <dl-machine.h>
-#include <sysdep-cancel.h>
#include <bits/libc-lock.h>
#include <tls.h>
@@ -73,16 +72,6 @@ struct sym_val
#include "do-lookup.h"
-static uint_fast32_t
-dl_new_hash (const char *s)
-{
- uint_fast32_t h = 5381;
- for (unsigned char c = *s; c != '\0'; c = *++s)
- h = h * 33 + c;
- return h & 0xffffffff;
-}
-
-
/* Add extra dependency on MAP to UNDEF_MAP. */
static int
internal_function
@@ -102,6 +91,11 @@ add_dependency (struct link_map *undef_map, struct link_map *map)
/* Make sure nobody can unload the object while we are at it. */
__rtld_lock_lock_recursive (GL(dl_load_lock));
+ /* Don't create cross-reference between modules which are
+ dynamically loaded by the same dlopen() call. */
+ if (undef_map->l_opencount == 0 && map->l_opencount == 0)
+ goto out;
+
/* Avoid references to objects which cannot be unloaded anyway. */
if (map->l_type != lt_loaded
|| (map->l_flags_1 & DF_1_NODELETE) != 0)
@@ -113,13 +107,14 @@ add_dependency (struct link_map *undef_map, struct link_map *map)
if (undef_map->l_type != lt_loaded
|| (undef_map->l_flags_1 & DF_1_NODELETE) != 0)
{
+ ++map->l_opencount;
map->l_flags_1 |= DF_1_NODELETE;
goto out;
}
/* Determine whether UNDEF_MAP already has a reference to MAP. First
look in the normal dependencies. */
- if (undef_map->l_initfini != NULL)
+ if (undef_map->l_searchlist.r_list != NULL)
{
list = undef_map->l_initfini;
@@ -177,6 +172,19 @@ add_dependency (struct link_map *undef_map, struct link_map *map)
if (__builtin_expect (act < undef_map->l_reldepsmax, 1))
undef_map->l_reldeps[undef_map->l_reldepsact++] = map;
+ if (map->l_searchlist.r_list != NULL)
+ /* And increment the counter in the referenced object. */
+ ++map->l_opencount;
+ else
+ /* We have to bump the counts for all dependencies since so far
+ this object was only a normal or transitive dependency.
+ Now it might be closed with _dl_close() directly. */
+ for (list = map->l_initfini; *list != NULL; ++list)
+ ++(*list)->l_opencount;
+
+ /* As if it is opened through _dl_open. */
+ ++map->l_direct_opencount;
+
/* Display information if we are debugging. */
if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0))
_dl_debug_printf ("\
@@ -201,17 +209,14 @@ add_dependency (struct link_map *undef_map, struct link_map *map)
static void
internal_function
_dl_debug_bindings (const char *undef_name, struct link_map *undef_map,
- const ElfW(Sym) **ref, struct sym_val *value,
+ const ElfW(Sym) **ref, struct r_scope_elem *symbol_scope[],
+ struct sym_val *value,
const struct r_found_version *version, int type_class,
int protected);
/* Search loaded objects' symbol tables for a definition of the symbol
- UNDEF_NAME, perhaps with a requested version for the symbol.
-
- We must never have calls to the audit functions inside this function
- or in any function which gets called. If this would happen the audit
- code might create a thread which can throw off all the scope locking. */
+ UNDEF_NAME, perhaps with a requested version for the symbol. */
lookup_t
internal_function
_dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map,
@@ -220,8 +225,7 @@ _dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map,
const struct r_found_version *version,
int type_class, int flags, struct link_map *skip_map)
{
- const uint_fast32_t new_hash = dl_new_hash (undef_name);
- unsigned long int old_hash = 0xffffffff;
+ const unsigned long int hash = _dl_elf_hash (undef_name);
struct sym_val current_value = { NULL, NULL };
struct r_scope_elem **scope = symbol_scope;
@@ -229,20 +233,23 @@ _dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map,
/* No other flag than DL_LOOKUP_ADD_DEPENDENCY is allowed if we look
up a versioned symbol. */
- assert (version == NULL || (flags & ~(DL_LOOKUP_ADD_DEPENDENCY)) == 0);
+ assert (version == NULL || flags == 0 || flags == DL_LOOKUP_ADD_DEPENDENCY);
size_t i = 0;
if (__builtin_expect (skip_map != NULL, 0))
- /* Search the relevant loaded objects for a definition. */
- while ((*scope)->r_list[i] != skip_map)
- ++i;
+ {
+ /* Search the relevant loaded objects for a definition. */
+ while ((*scope)->r_list[i] != skip_map)
+ ++i;
+
+ assert (i < (*scope)->r_nlist);
+ }
/* Search the relevant loaded objects for a definition. */
for (size_t start = i; *scope != NULL; start = 0, ++scope)
{
- int res = do_lookup_x (undef_name, new_hash, &old_hash, *ref,
- &current_value, *scope, start, version, flags,
- skip_map, type_class);
+ int res = do_lookup_x (undef_name, hash, *ref, &current_value, *scope,
+ start, version, flags, skip_map, type_class);
if (res > 0)
break;
@@ -313,9 +320,9 @@ _dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map,
struct sym_val protected_value = { NULL, NULL };
for (scope = symbol_scope; *scope != NULL; i = 0, ++scope)
- if (do_lookup_x (undef_name, new_hash, &old_hash, *ref,
- &protected_value, *scope, i, version, flags,
- skip_map, ELF_RTYPE_CLASS_PLT) != 0)
+ if (do_lookup_x (undef_name, hash, *ref, &protected_value,
+ *scope, i, version, flags, skip_map,
+ ELF_RTYPE_CLASS_PLT) != 0)
break;
if (protected_value.s != NULL && protected_value.m != undef_map)
@@ -338,15 +345,16 @@ _dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map,
&& add_dependency (undef_map, current_value.m) < 0)
/* Something went wrong. Perhaps the object we tried to reference
was just removed. Try finding another definition. */
- return _dl_lookup_symbol_x (undef_name, undef_map, ref, symbol_scope,
- version, type_class, flags, skip_map);
+ return _dl_lookup_symbol_x (undef_name, undef_map, ref,
+ symbol_scope, version, type_class,
+ flags, skip_map);
/* The object is used. */
current_value.m->l_used = 1;
if (__builtin_expect (GLRO(dl_debug_mask)
& (DL_DEBUG_BINDINGS|DL_DEBUG_PRELINK), 0))
- _dl_debug_bindings (undef_name, undef_map, ref,
+ _dl_debug_bindings (undef_name, undef_map, ref, symbol_scope,
&current_value, version, type_class, protected);
*ref = current_value.s;
@@ -363,31 +371,6 @@ _dl_setup_hash (struct link_map *map)
Elf_Symndx *hash;
Elf_Symndx nchain;
- if (__builtin_expect (map->l_info[DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM
- + DT_THISPROCNUM + DT_VERSIONTAGNUM
- + DT_EXTRANUM + DT_VALNUM] != NULL, 1))
- {
- Elf32_Word *hash32
- = (void *) D_PTR (map, l_info[DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM
- + DT_THISPROCNUM + DT_VERSIONTAGNUM
- + DT_EXTRANUM + DT_VALNUM]);
- map->l_nbuckets = *hash32++;
- Elf32_Word symbias = *hash32++;
- Elf32_Word bitmask_nwords = *hash32++;
- /* Must be a power of two. */
- assert ((bitmask_nwords & (bitmask_nwords - 1)) == 0);
- map->l_gnu_bitmask_idxbits = bitmask_nwords - 1;
- map->l_gnu_shift = *hash32++;
-
- map->l_gnu_bitmask = (ElfW(Addr) *) hash32;
- hash32 += __ELF_NATIVE_CLASS / 32 * bitmask_nwords;
-
- map->l_gnu_buckets = hash32;
- hash32 += map->l_nbuckets;
- map->l_gnu_chain_zero = hash32 - symbias;
- return;
- }
-
if (!map->l_info[DT_HASH])
return;
hash = (void *) D_PTR (map, l_info[DT_HASH]);
@@ -403,7 +386,8 @@ _dl_setup_hash (struct link_map *map)
static void
internal_function
_dl_debug_bindings (const char *undef_name, struct link_map *undef_map,
- const ElfW(Sym) **ref, struct sym_val *value,
+ const ElfW(Sym) **ref, struct r_scope_elem *symbol_scope[],
+ struct sym_val *value,
const struct r_found_version *version, int type_class,
int protected)
{
@@ -411,13 +395,11 @@ _dl_debug_bindings (const char *undef_name, struct link_map *undef_map,
if (GLRO(dl_debug_mask) & DL_DEBUG_BINDINGS)
{
- _dl_debug_printf ("binding file %s [%lu] to %s [%lu]: %s symbol `%s'",
+ _dl_debug_printf ("binding file %s to %s: %s symbol `%s'",
(reference_name[0]
? reference_name
: (rtld_progname ?: "<main program>")),
- undef_map->l_ns,
value->m->l_name[0] ? value->m->l_name : rtld_progname,
- value->m->l_ns,
protected ? "protected" : "normal", undef_name);
if (version)
_dl_debug_printf_c (" [%s]\n", version->name);
@@ -434,10 +416,9 @@ _dl_debug_bindings (const char *undef_name, struct link_map *undef_map,
|| GLRO(dl_trace_prelink_map) == GL(dl_ns)[LM_ID_BASE]._ns_loaded)
&& undef_map != GL(dl_ns)[LM_ID_BASE]._ns_loaded)
{
- const uint_fast32_t new_hash = dl_new_hash (undef_name);
- unsigned long int old_hash = 0xffffffff;
+ const unsigned long int hash = _dl_elf_hash (undef_name);
- do_lookup_x (undef_name, new_hash, &old_hash, *ref, &val,
+ do_lookup_x (undef_name, hash, *ref, &val,
undef_map->l_local_scope[0], 0, version, 0, NULL,
type_class);