mirror of git://sourceware.org/git/glibc.git
Remove do-lookup.h.
It is not necessary/useful anymore to have the content separate from dl-lookup.c.
This commit is contained in:
Ulrich Drepper
parent
339717d5f1
commit
786b74f41a
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@ -1,5 +1,8 @@
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2009-07-10 Ulrich Drepper <drepper@redhat.com>
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2009-07-10 Ulrich Drepper <drepper@redhat.com>
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* elf/do-lookup.h: Removed after folding content into...
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* elf/dl-lookup.c: ...here.
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* sysdeps/unix/sysv/linux/sys/epoll.h: Fix comment.
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* sysdeps/unix/sysv/linux/sys/epoll.h: Fix comment.
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2009-07-09 Ulrich Drepper <drepper@redhat.com>
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2009-07-09 Ulrich Drepper <drepper@redhat.com>
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@ -47,7 +47,7 @@ distribute := rtld-Rules \
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dl-cache.h dl-hash.h soinit.c sofini.c ldd.bash.in \
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dl-cache.h dl-hash.h soinit.c sofini.c ldd.bash.in \
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genrtldtbl.awk atomicity.h dl-procinfo.h ldsodefs.h \
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genrtldtbl.awk atomicity.h dl-procinfo.h ldsodefs.h \
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dl-librecon.h interp.c sln.c dl-dst.h hp-timing.h \
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dl-librecon.h interp.c sln.c dl-dst.h hp-timing.h \
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do-lookup.h dl-lookupcfg.h sprof.c gen-trusted-dirs.awk \
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dl-lookupcfg.h sprof.c gen-trusted-dirs.awk \
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testobj1.c testobj2.c testobj3.c testobj4.c testobj5.c \
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testobj1.c testobj2.c testobj3.c testobj4.c testobj5.c \
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testobj6.c testobj1_1.c failobj.c unloadmod.c \
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testobj6.c testobj1_1.c failobj.c unloadmod.c \
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ldconfig.h ldconfig.c cache.c readlib.c readelflib.c \
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ldconfig.h ldconfig.c cache.c readlib.c readelflib.c \
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367
elf/dl-lookup.c
367
elf/dl-lookup.c
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@ -69,8 +69,371 @@ struct sym_val
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#endif
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#endif
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/* The actual lookup code. */
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/* Inner part of the lookup functions. We return a value > 0 if we
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#include "do-lookup.h"
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found the symbol, the value 0 if nothing is found and < 0 if
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something bad happened. */
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static int
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__attribute_noinline__
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do_lookup_x (const char *undef_name, uint_fast32_t new_hash,
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unsigned long int *old_hash, const ElfW(Sym) *ref,
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struct sym_val *result, struct r_scope_elem *scope, size_t i,
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const struct r_found_version *const version, int flags,
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struct link_map *skip, int type_class, struct link_map *undef_map)
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{
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size_t n = scope->r_nlist;
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/* Make sure we read the value before proceeding. Otherwise we
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might use r_list pointing to the initial scope and r_nlist being
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the value after a resize. That is the only path in dl-open.c not
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protected by GSCOPE. A read barrier here might be to expensive. */
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__asm volatile ("" : "+r" (n), "+m" (scope->r_list));
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struct link_map **list = scope->r_list;
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do
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{
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/* These variables are used in the nested function. */
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Elf_Symndx symidx;
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int num_versions = 0;
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const ElfW(Sym) *versioned_sym = NULL;
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const struct link_map *map = list[i]->l_real;
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/* Here come the extra test needed for `_dl_lookup_symbol_skip'. */
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if (map == skip)
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continue;
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/* Don't search the executable when resolving a copy reloc. */
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if ((type_class & ELF_RTYPE_CLASS_COPY) && map->l_type == lt_executable)
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continue;
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/* Do not look into objects which are going to be removed. */
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if (map->l_removed)
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continue;
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/* Print some debugging info if wanted. */
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if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_SYMBOLS, 0))
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_dl_debug_printf ("symbol=%s; lookup in file=%s [%lu]\n",
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undef_name,
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map->l_name[0] ? map->l_name : rtld_progname,
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map->l_ns);
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/* If the hash table is empty there is nothing to do here. */
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if (map->l_nbuckets == 0)
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continue;
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/* The tables for this map. */
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const ElfW(Sym) *symtab = (const void *) D_PTR (map, l_info[DT_SYMTAB]);
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const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
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/* Nested routine to check whether the symbol matches. */
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const ElfW(Sym) *
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__attribute_noinline__
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check_match (const ElfW(Sym) *sym)
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{
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unsigned int stt = ELFW(ST_TYPE) (sym->st_info);
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assert (ELF_RTYPE_CLASS_PLT == 1);
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if (__builtin_expect ((sym->st_value == 0 /* No value. */
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&& stt != STT_TLS)
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|| (type_class & (sym->st_shndx == SHN_UNDEF)),
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0))
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return NULL;
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/* Ignore all but STT_NOTYPE, STT_OBJECT, STT_FUNC,
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STT_COMMON, STT_TLS, and STT_GNU_IFUNC since these are no
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code/data definitions. */
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#define ALLOWED_STT \
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((1 << STT_NOTYPE) | (1 << STT_OBJECT) | (1 << STT_FUNC) \
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| (1 << STT_COMMON) | (1 << STT_TLS) | (1 << STT_GNU_IFUNC))
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if (__builtin_expect (((1 << stt) & ALLOWED_STT) == 0, 0))
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return NULL;
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if (sym != ref && strcmp (strtab + sym->st_name, undef_name))
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/* Not the symbol we are looking for. */
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return NULL;
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const ElfW(Half) *verstab = map->l_versyms;
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if (version != NULL)
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{
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if (__builtin_expect (verstab == NULL, 0))
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{
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/* We need a versioned symbol but haven't found any. If
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this is the object which is referenced in the verneed
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entry it is a bug in the library since a symbol must
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not simply disappear.
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It would also be a bug in the object since it means that
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the list of required versions is incomplete and so the
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tests in dl-version.c haven't found a problem.*/
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assert (version->filename == NULL
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|| ! _dl_name_match_p (version->filename, map));
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/* Otherwise we accept the symbol. */
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}
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else
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{
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/* We can match the version information or use the
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default one if it is not hidden. */
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ElfW(Half) ndx = verstab[symidx] & 0x7fff;
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if ((map->l_versions[ndx].hash != version->hash
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|| strcmp (map->l_versions[ndx].name, version->name))
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&& (version->hidden || map->l_versions[ndx].hash
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|| (verstab[symidx] & 0x8000)))
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/* It's not the version we want. */
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return NULL;
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}
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}
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else
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{
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/* No specific version is selected. There are two ways we
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can got here:
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- a binary which does not include versioning information
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is loaded
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- dlsym() instead of dlvsym() is used to get a symbol which
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might exist in more than one form
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If the library does not provide symbol version information
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there is no problem at at: we simply use the symbol if it
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is defined.
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These two lookups need to be handled differently if the
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library defines versions. In the case of the old
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unversioned application the oldest (default) version
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should be used. In case of a dlsym() call the latest and
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public interface should be returned. */
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if (verstab != NULL)
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{
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if ((verstab[symidx] & 0x7fff)
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>= ((flags & DL_LOOKUP_RETURN_NEWEST) ? 2 : 3))
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{
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/* Don't accept hidden symbols. */
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if ((verstab[symidx] & 0x8000) == 0
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&& num_versions++ == 0)
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/* No version so far. */
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versioned_sym = sym;
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return NULL;
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}
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}
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}
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/* There cannot be another entry for this symbol so stop here. */
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return sym;
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}
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const ElfW(Sym) *sym;
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const ElfW(Addr) *bitmask = map->l_gnu_bitmask;
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if (__builtin_expect (bitmask != NULL, 1))
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{
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ElfW(Addr) bitmask_word
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= bitmask[(new_hash / __ELF_NATIVE_CLASS)
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& map->l_gnu_bitmask_idxbits];
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unsigned int hashbit1 = new_hash & (__ELF_NATIVE_CLASS - 1);
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unsigned int hashbit2 = ((new_hash >> map->l_gnu_shift)
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& (__ELF_NATIVE_CLASS - 1));
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if (__builtin_expect ((bitmask_word >> hashbit1)
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& (bitmask_word >> hashbit2) & 1, 0))
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{
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Elf32_Word bucket = map->l_gnu_buckets[new_hash
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% map->l_nbuckets];
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if (bucket != 0)
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{
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const Elf32_Word *hasharr = &map->l_gnu_chain_zero[bucket];
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do
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if (((*hasharr ^ new_hash) >> 1) == 0)
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{
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symidx = hasharr - map->l_gnu_chain_zero;
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sym = check_match (&symtab[symidx]);
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if (sym != NULL)
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goto found_it;
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}
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while ((*hasharr++ & 1u) == 0);
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}
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}
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/* No symbol found. */
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symidx = SHN_UNDEF;
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}
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else
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{
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if (*old_hash == 0xffffffff)
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*old_hash = _dl_elf_hash (undef_name);
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/* Use the old SysV-style hash table. Search the appropriate
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hash bucket in this object's symbol table for a definition
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for the same symbol name. */
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for (symidx = map->l_buckets[*old_hash % map->l_nbuckets];
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symidx != STN_UNDEF;
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symidx = map->l_chain[symidx])
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{
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sym = check_match (&symtab[symidx]);
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if (sym != NULL)
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goto found_it;
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}
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}
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/* If we have seen exactly one versioned symbol while we are
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looking for an unversioned symbol and the version is not the
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default version we still accept this symbol since there are
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no possible ambiguities. */
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sym = num_versions == 1 ? versioned_sym : NULL;
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if (sym != NULL)
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{
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found_it:
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switch (__builtin_expect (ELFW(ST_BIND) (sym->st_info), STB_GLOBAL))
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{
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case STB_WEAK:
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/* Weak definition. Use this value if we don't find another. */
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if (__builtin_expect (GLRO(dl_dynamic_weak), 0))
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{
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if (! result->s)
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{
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result->s = sym;
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result->m = (struct link_map *) map;
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|
}
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|
break;
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|
}
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/* FALLTHROUGH */
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case STB_GLOBAL:
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success:
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/* Global definition. Just what we need. */
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result->s = sym;
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result->m = (struct link_map *) map;
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return 1;
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case STB_GNU_UNIQUE:;
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/* We have to determine whether we already found a
|
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symbol with this name before. If not then we have to
|
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|
add it to the search table. If we already found a
|
||||||
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definition we have to use it. */
|
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|
void enter (struct unique_sym *table, size_t size,
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|
unsigned int hash, const char *name,
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const ElfW(Sym) *sym, const struct link_map *map)
|
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|
{
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|
size_t idx = hash % size;
|
||||||
|
size_t hash2 = 1 + hash % (size - 2);
|
||||||
|
while (1)
|
||||||
|
{
|
||||||
|
if (table[idx].hashval == 0)
|
||||||
|
{
|
||||||
|
table[idx].hashval = hash;
|
||||||
|
table[idx].name = strtab + sym->st_name;
|
||||||
|
if ((type_class & ELF_RTYPE_CLASS_COPY) != 0)
|
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|
{
|
||||||
|
table[idx].sym = ref;
|
||||||
|
table[idx].map = undef_map;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
table[idx].sym = sym;
|
||||||
|
table[idx].map = map;
|
||||||
|
}
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
|
||||||
|
idx += hash2;
|
||||||
|
if (idx >= size)
|
||||||
|
idx -= size;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
struct unique_sym_table *tab
|
||||||
|
= &GL(dl_ns)[map->l_ns]._ns_unique_sym_table;
|
||||||
|
|
||||||
|
__rtld_lock_lock_recursive (tab->lock);
|
||||||
|
|
||||||
|
struct unique_sym *entries = tab->entries;
|
||||||
|
size_t size = tab->size;
|
||||||
|
if (entries != NULL)
|
||||||
|
{
|
||||||
|
size_t idx = new_hash % size;
|
||||||
|
size_t hash2 = 1 + new_hash % (size - 2);
|
||||||
|
while (1)
|
||||||
|
{
|
||||||
|
if (entries[idx].hashval == new_hash
|
||||||
|
&& strcmp (entries[idx].name, undef_name) == 0)
|
||||||
|
{
|
||||||
|
result->s = entries[idx].sym;
|
||||||
|
result->m = (struct link_map *) entries[idx].map;
|
||||||
|
__rtld_lock_unlock_recursive (tab->lock);
|
||||||
|
return 1;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (entries[idx].hashval == 0
|
||||||
|
&& entries[idx].name == NULL)
|
||||||
|
break;
|
||||||
|
|
||||||
|
idx += hash2;
|
||||||
|
if (idx >= size)
|
||||||
|
idx -= size;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (size * 3 <= tab->n_elements)
|
||||||
|
{
|
||||||
|
/* Expand the table. */
|
||||||
|
size_t newsize = _dl_higher_prime_number (size);
|
||||||
|
struct unique_sym *newentries
|
||||||
|
= calloc (sizeof (struct unique_sym), newsize);
|
||||||
|
if (newentries == NULL)
|
||||||
|
{
|
||||||
|
nomem:
|
||||||
|
__rtld_lock_unlock_recursive (tab->lock);
|
||||||
|
_dl_fatal_printf ("out of memory\n");
|
||||||
|
}
|
||||||
|
|
||||||
|
for (idx = 0; idx < size; ++idx)
|
||||||
|
if (entries[idx].hashval != 0)
|
||||||
|
enter (newentries, newsize, entries[idx].hashval,
|
||||||
|
entries[idx].name, entries[idx].sym,
|
||||||
|
entries[idx].map);
|
||||||
|
|
||||||
|
tab->free (entries);
|
||||||
|
tab->size = newsize;
|
||||||
|
entries = tab->entries = newentries;
|
||||||
|
tab->free = free;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
#define INITIAL_NUNIQUE_SYM_TABLE 31
|
||||||
|
size = INITIAL_NUNIQUE_SYM_TABLE;
|
||||||
|
entries = calloc (sizeof (struct unique_sym), size);
|
||||||
|
if (entries == NULL)
|
||||||
|
goto nomem;
|
||||||
|
|
||||||
|
tab->entries = entries;
|
||||||
|
tab->size = size;
|
||||||
|
tab->free = free;
|
||||||
|
}
|
||||||
|
|
||||||
|
enter (entries, size, new_hash, strtab + sym->st_name, sym, map);
|
||||||
|
++tab->n_elements;
|
||||||
|
|
||||||
|
__rtld_lock_unlock_recursive (tab->lock);
|
||||||
|
|
||||||
|
goto success;
|
||||||
|
|
||||||
|
default:
|
||||||
|
/* Local symbols are ignored. */
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/* If this current map is the one mentioned in the verneed entry
|
||||||
|
and we have not found a weak entry, it is a bug. */
|
||||||
|
if (symidx == STN_UNDEF && version != NULL && version->filename != NULL
|
||||||
|
&& __builtin_expect (_dl_name_match_p (version->filename, map), 0))
|
||||||
|
return -1;
|
||||||
|
}
|
||||||
|
while (++i < n);
|
||||||
|
|
||||||
|
/* We have not found anything until now. */
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
static uint_fast32_t
|
static uint_fast32_t
|
||||||
|
|
|
||||||
385
elf/do-lookup.h
385
elf/do-lookup.h
|
|
@ -1,385 +0,0 @@
|
||||||
/* Look up a symbol in the loaded objects.
|
|
||||||
Copyright (C) 1995-2007, 2008, 2009 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, write to the Free
|
|
||||||
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
||||||
02111-1307 USA. */
|
|
||||||
|
|
||||||
|
|
||||||
/* Inner part of the lookup functions. We return a value > 0 if we
|
|
||||||
found the symbol, the value 0 if nothing is found and < 0 if
|
|
||||||
something bad happened. */
|
|
||||||
static int
|
|
||||||
__attribute_noinline__
|
|
||||||
do_lookup_x (const char *undef_name, uint_fast32_t new_hash,
|
|
||||||
unsigned long int *old_hash, const ElfW(Sym) *ref,
|
|
||||||
struct sym_val *result, struct r_scope_elem *scope, size_t i,
|
|
||||||
const struct r_found_version *const version, int flags,
|
|
||||||
struct link_map *skip, int type_class, struct link_map *undef_map)
|
|
||||||
{
|
|
||||||
size_t n = scope->r_nlist;
|
|
||||||
/* Make sure we read the value before proceeding. Otherwise we
|
|
||||||
might use r_list pointing to the initial scope and r_nlist being
|
|
||||||
the value after a resize. That is the only path in dl-open.c not
|
|
||||||
protected by GSCOPE. A read barrier here might be to expensive. */
|
|
||||||
__asm volatile ("" : "+r" (n), "+m" (scope->r_list));
|
|
||||||
struct link_map **list = scope->r_list;
|
|
||||||
|
|
||||||
do
|
|
||||||
{
|
|
||||||
/* These variables are used in the nested function. */
|
|
||||||
Elf_Symndx symidx;
|
|
||||||
int num_versions = 0;
|
|
||||||
const ElfW(Sym) *versioned_sym = NULL;
|
|
||||||
|
|
||||||
const struct link_map *map = list[i]->l_real;
|
|
||||||
|
|
||||||
/* Here come the extra test needed for `_dl_lookup_symbol_skip'. */
|
|
||||||
if (map == skip)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
/* Don't search the executable when resolving a copy reloc. */
|
|
||||||
if ((type_class & ELF_RTYPE_CLASS_COPY) && map->l_type == lt_executable)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
/* Do not look into objects which are going to be removed. */
|
|
||||||
if (map->l_removed)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
/* Print some debugging info if wanted. */
|
|
||||||
if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_SYMBOLS, 0))
|
|
||||||
_dl_debug_printf ("symbol=%s; lookup in file=%s [%lu]\n",
|
|
||||||
undef_name,
|
|
||||||
map->l_name[0] ? map->l_name : rtld_progname,
|
|
||||||
map->l_ns);
|
|
||||||
|
|
||||||
/* If the hash table is empty there is nothing to do here. */
|
|
||||||
if (map->l_nbuckets == 0)
|
|
||||||
continue;
|
|
||||||
|
|
||||||
/* The tables for this map. */
|
|
||||||
const ElfW(Sym) *symtab = (const void *) D_PTR (map, l_info[DT_SYMTAB]);
|
|
||||||
const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
|
|
||||||
|
|
||||||
|
|
||||||
/* Nested routine to check whether the symbol matches. */
|
|
||||||
const ElfW(Sym) *
|
|
||||||
__attribute_noinline__
|
|
||||||
check_match (const ElfW(Sym) *sym)
|
|
||||||
{
|
|
||||||
unsigned int stt = ELFW(ST_TYPE) (sym->st_info);
|
|
||||||
assert (ELF_RTYPE_CLASS_PLT == 1);
|
|
||||||
if (__builtin_expect ((sym->st_value == 0 /* No value. */
|
|
||||||
&& stt != STT_TLS)
|
|
||||||
|| (type_class & (sym->st_shndx == SHN_UNDEF)),
|
|
||||||
0))
|
|
||||||
return NULL;
|
|
||||||
|
|
||||||
/* Ignore all but STT_NOTYPE, STT_OBJECT, STT_FUNC,
|
|
||||||
STT_COMMON, STT_TLS, and STT_GNU_IFUNC since these are no
|
|
||||||
code/data definitions. */
|
|
||||||
#define ALLOWED_STT \
|
|
||||||
((1 << STT_NOTYPE) | (1 << STT_OBJECT) | (1 << STT_FUNC) \
|
|
||||||
| (1 << STT_COMMON) | (1 << STT_TLS) | (1 << STT_GNU_IFUNC))
|
|
||||||
if (__builtin_expect (((1 << stt) & ALLOWED_STT) == 0, 0))
|
|
||||||
return NULL;
|
|
||||||
|
|
||||||
if (sym != ref && strcmp (strtab + sym->st_name, undef_name))
|
|
||||||
/* Not the symbol we are looking for. */
|
|
||||||
return NULL;
|
|
||||||
|
|
||||||
const ElfW(Half) *verstab = map->l_versyms;
|
|
||||||
if (version != NULL)
|
|
||||||
{
|
|
||||||
if (__builtin_expect (verstab == NULL, 0))
|
|
||||||
{
|
|
||||||
/* We need a versioned symbol but haven't found any. If
|
|
||||||
this is the object which is referenced in the verneed
|
|
||||||
entry it is a bug in the library since a symbol must
|
|
||||||
not simply disappear.
|
|
||||||
|
|
||||||
It would also be a bug in the object since it means that
|
|
||||||
the list of required versions is incomplete and so the
|
|
||||||
tests in dl-version.c haven't found a problem.*/
|
|
||||||
assert (version->filename == NULL
|
|
||||||
|| ! _dl_name_match_p (version->filename, map));
|
|
||||||
|
|
||||||
/* Otherwise we accept the symbol. */
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* We can match the version information or use the
|
|
||||||
default one if it is not hidden. */
|
|
||||||
ElfW(Half) ndx = verstab[symidx] & 0x7fff;
|
|
||||||
if ((map->l_versions[ndx].hash != version->hash
|
|
||||||
|| strcmp (map->l_versions[ndx].name, version->name))
|
|
||||||
&& (version->hidden || map->l_versions[ndx].hash
|
|
||||||
|| (verstab[symidx] & 0x8000)))
|
|
||||||
/* It's not the version we want. */
|
|
||||||
return NULL;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
/* No specific version is selected. There are two ways we
|
|
||||||
can got here:
|
|
||||||
|
|
||||||
- a binary which does not include versioning information
|
|
||||||
is loaded
|
|
||||||
|
|
||||||
- dlsym() instead of dlvsym() is used to get a symbol which
|
|
||||||
might exist in more than one form
|
|
||||||
|
|
||||||
If the library does not provide symbol version information
|
|
||||||
there is no problem at at: we simply use the symbol if it
|
|
||||||
is defined.
|
|
||||||
|
|
||||||
These two lookups need to be handled differently if the
|
|
||||||
library defines versions. In the case of the old
|
|
||||||
unversioned application the oldest (default) version
|
|
||||||
should be used. In case of a dlsym() call the latest and
|
|
||||||
public interface should be returned. */
|
|
||||||
if (verstab != NULL)
|
|
||||||
{
|
|
||||||
if ((verstab[symidx] & 0x7fff)
|
|
||||||
>= ((flags & DL_LOOKUP_RETURN_NEWEST) ? 2 : 3))
|
|
||||||
{
|
|
||||||
/* Don't accept hidden symbols. */
|
|
||||||
if ((verstab[symidx] & 0x8000) == 0
|
|
||||||
&& num_versions++ == 0)
|
|
||||||
/* No version so far. */
|
|
||||||
versioned_sym = sym;
|
|
||||||
|
|
||||||
return NULL;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/* There cannot be another entry for this symbol so stop here. */
|
|
||||||
return sym;
|
|
||||||
}
|
|
||||||
|
|
||||||
const ElfW(Sym) *sym;
|
|
||||||
const ElfW(Addr) *bitmask = map->l_gnu_bitmask;
|
|
||||||
if (__builtin_expect (bitmask != NULL, 1))
|
|
||||||
{
|
|
||||||
ElfW(Addr) bitmask_word
|
|
||||||
= bitmask[(new_hash / __ELF_NATIVE_CLASS)
|
|
||||||
& map->l_gnu_bitmask_idxbits];
|
|
||||||
|
|
||||||
unsigned int hashbit1 = new_hash & (__ELF_NATIVE_CLASS - 1);
|
|
||||||
unsigned int hashbit2 = ((new_hash >> map->l_gnu_shift)
|
|
||||||
& (__ELF_NATIVE_CLASS - 1));
|
|
||||||
|
|
||||||
if (__builtin_expect ((bitmask_word >> hashbit1)
|
|
||||||
& (bitmask_word >> hashbit2) & 1, 0))
|
|
||||||
{
|
|
||||||
Elf32_Word bucket = map->l_gnu_buckets[new_hash
|
|
||||||
% map->l_nbuckets];
|
|
||||||
if (bucket != 0)
|
|
||||||
{
|
|
||||||
const Elf32_Word *hasharr = &map->l_gnu_chain_zero[bucket];
|
|
||||||
|
|
||||||
do
|
|
||||||
if (((*hasharr ^ new_hash) >> 1) == 0)
|
|
||||||
{
|
|
||||||
symidx = hasharr - map->l_gnu_chain_zero;
|
|
||||||
sym = check_match (&symtab[symidx]);
|
|
||||||
if (sym != NULL)
|
|
||||||
goto found_it;
|
|
||||||
}
|
|
||||||
while ((*hasharr++ & 1u) == 0);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
/* No symbol found. */
|
|
||||||
symidx = SHN_UNDEF;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
if (*old_hash == 0xffffffff)
|
|
||||||
*old_hash = _dl_elf_hash (undef_name);
|
|
||||||
|
|
||||||
/* Use the old SysV-style hash table. Search the appropriate
|
|
||||||
hash bucket in this object's symbol table for a definition
|
|
||||||
for the same symbol name. */
|
|
||||||
for (symidx = map->l_buckets[*old_hash % map->l_nbuckets];
|
|
||||||
symidx != STN_UNDEF;
|
|
||||||
symidx = map->l_chain[symidx])
|
|
||||||
{
|
|
||||||
sym = check_match (&symtab[symidx]);
|
|
||||||
if (sym != NULL)
|
|
||||||
goto found_it;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/* If we have seen exactly one versioned symbol while we are
|
|
||||||
looking for an unversioned symbol and the version is not the
|
|
||||||
default version we still accept this symbol since there are
|
|
||||||
no possible ambiguities. */
|
|
||||||
sym = num_versions == 1 ? versioned_sym : NULL;
|
|
||||||
|
|
||||||
if (sym != NULL)
|
|
||||||
{
|
|
||||||
found_it:
|
|
||||||
switch (__builtin_expect (ELFW(ST_BIND) (sym->st_info), STB_GLOBAL))
|
|
||||||
{
|
|
||||||
case STB_WEAK:
|
|
||||||
/* Weak definition. Use this value if we don't find another. */
|
|
||||||
if (__builtin_expect (GLRO(dl_dynamic_weak), 0))
|
|
||||||
{
|
|
||||||
if (! result->s)
|
|
||||||
{
|
|
||||||
result->s = sym;
|
|
||||||
result->m = (struct link_map *) map;
|
|
||||||
}
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
/* FALLTHROUGH */
|
|
||||||
case STB_GLOBAL:
|
|
||||||
success:
|
|
||||||
/* Global definition. Just what we need. */
|
|
||||||
result->s = sym;
|
|
||||||
result->m = (struct link_map *) map;
|
|
||||||
return 1;
|
|
||||||
|
|
||||||
case STB_GNU_UNIQUE:;
|
|
||||||
/* We have to determine whether we already found a
|
|
||||||
symbol with this name before. If not then we have to
|
|
||||||
add it to the search table. If we already found a
|
|
||||||
definition we have to use it. */
|
|
||||||
void enter (struct unique_sym *table, size_t size,
|
|
||||||
unsigned int hash, const char *name,
|
|
||||||
const ElfW(Sym) *sym, const struct link_map *map)
|
|
||||||
{
|
|
||||||
size_t idx = hash % size;
|
|
||||||
size_t hash2 = 1 + hash % (size - 2);
|
|
||||||
while (1)
|
|
||||||
{
|
|
||||||
if (table[idx].hashval == 0)
|
|
||||||
{
|
|
||||||
table[idx].hashval = hash;
|
|
||||||
table[idx].name = strtab + sym->st_name;
|
|
||||||
if ((type_class & ELF_RTYPE_CLASS_COPY) != 0)
|
|
||||||
{
|
|
||||||
table[idx].sym = ref;
|
|
||||||
table[idx].map = undef_map;
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
table[idx].sym = sym;
|
|
||||||
table[idx].map = map;
|
|
||||||
}
|
|
||||||
return;
|
|
||||||
}
|
|
||||||
|
|
||||||
idx += hash2;
|
|
||||||
if (idx >= size)
|
|
||||||
idx -= size;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
struct unique_sym_table *tab
|
|
||||||
= &GL(dl_ns)[map->l_ns]._ns_unique_sym_table;
|
|
||||||
|
|
||||||
__rtld_lock_lock_recursive (tab->lock);
|
|
||||||
|
|
||||||
struct unique_sym *entries = tab->entries;
|
|
||||||
size_t size = tab->size;
|
|
||||||
if (entries != NULL)
|
|
||||||
{
|
|
||||||
size_t idx = new_hash % size;
|
|
||||||
size_t hash2 = 1 + new_hash % (size - 2);
|
|
||||||
while (1)
|
|
||||||
{
|
|
||||||
if (entries[idx].hashval == new_hash
|
|
||||||
&& strcmp (entries[idx].name, undef_name) == 0)
|
|
||||||
{
|
|
||||||
result->s = entries[idx].sym;
|
|
||||||
result->m = (struct link_map *) entries[idx].map;
|
|
||||||
__rtld_lock_unlock_recursive (tab->lock);
|
|
||||||
return 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (entries[idx].hashval == 0
|
|
||||||
&& entries[idx].name == NULL)
|
|
||||||
break;
|
|
||||||
|
|
||||||
idx += hash2;
|
|
||||||
if (idx >= size)
|
|
||||||
idx -= size;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (size * 3 <= tab->n_elements)
|
|
||||||
{
|
|
||||||
/* Expand the table. */
|
|
||||||
size_t newsize = _dl_higher_prime_number (size);
|
|
||||||
struct unique_sym *newentries
|
|
||||||
= calloc (sizeof (struct unique_sym), newsize);
|
|
||||||
if (newentries == NULL)
|
|
||||||
{
|
|
||||||
nomem:
|
|
||||||
__rtld_lock_unlock_recursive (tab->lock);
|
|
||||||
_dl_fatal_printf ("out of memory\n");
|
|
||||||
}
|
|
||||||
|
|
||||||
for (idx = 0; idx < size; ++idx)
|
|
||||||
if (entries[idx].hashval != 0)
|
|
||||||
enter (newentries, newsize, entries[idx].hashval,
|
|
||||||
entries[idx].name, entries[idx].sym,
|
|
||||||
entries[idx].map);
|
|
||||||
|
|
||||||
tab->free (entries);
|
|
||||||
tab->size = newsize;
|
|
||||||
entries = tab->entries = newentries;
|
|
||||||
tab->free = free;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
else
|
|
||||||
{
|
|
||||||
#define INITIAL_NUNIQUE_SYM_TABLE 31
|
|
||||||
size = INITIAL_NUNIQUE_SYM_TABLE;
|
|
||||||
entries = calloc (sizeof (struct unique_sym), size);
|
|
||||||
if (entries == NULL)
|
|
||||||
goto nomem;
|
|
||||||
|
|
||||||
tab->entries = entries;
|
|
||||||
tab->size = size;
|
|
||||||
tab->free = free;
|
|
||||||
}
|
|
||||||
|
|
||||||
enter (entries, size, new_hash, strtab + sym->st_name, sym, map);
|
|
||||||
++tab->n_elements;
|
|
||||||
|
|
||||||
__rtld_lock_unlock_recursive (tab->lock);
|
|
||||||
|
|
||||||
goto success;
|
|
||||||
|
|
||||||
default:
|
|
||||||
/* Local symbols are ignored. */
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/* If this current map is the one mentioned in the verneed entry
|
|
||||||
and we have not found a weak entry, it is a bug. */
|
|
||||||
if (symidx == STN_UNDEF && version != NULL && version->filename != NULL
|
|
||||||
&& __builtin_expect (_dl_name_match_p (version->filename, map), 0))
|
|
||||||
return -1;
|
|
||||||
}
|
|
||||||
while (++i < n);
|
|
||||||
|
|
||||||
/* We have not found anything until now. */
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
Loading…
Reference in New Issue