diff options
Diffstat (limited to 'elf/dl-lookup.c')
| -rw-r--r-- | elf/dl-lookup.c | 56 |
1 files changed, 47 insertions, 9 deletions
diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c index 5a7bed16e5..7cfcc620a7 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) 1995-2002, 2003, 2004, 2005 Free Software Foundation, Inc. + Copyright (C) 1995-2005, 2006 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 @@ -72,6 +72,16 @@ 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 @@ -206,7 +216,8 @@ _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 unsigned long int hash = _dl_elf_hash (undef_name); + const uint_fast32_t new_hash = dl_new_hash (undef_name); + unsigned long int old_hash = 0xffffffff; struct sym_val current_value = { NULL, NULL }; struct r_scope_elem **scope = symbol_scope; @@ -229,8 +240,9 @@ _dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map, /* 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, hash, *ref, ¤t_value, *scope, - start, version, flags, skip_map, type_class); + int res = do_lookup_x (undef_name, new_hash, &old_hash, *ref, + ¤t_value, *scope, start, version, flags, + skip_map, type_class); if (res > 0) break; @@ -301,9 +313,9 @@ _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, hash, *ref, &protected_value, - *scope, i, version, flags, skip_map, - ELF_RTYPE_CLASS_PLT) != 0) + if (do_lookup_x (undef_name, new_hash, &old_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) @@ -352,6 +364,31 @@ _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]); @@ -399,9 +436,10 @@ _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 unsigned long int hash = _dl_elf_hash (undef_name); + const uint_fast32_t new_hash = dl_new_hash (undef_name); + unsigned long int old_hash = 0xffffffff; - do_lookup_x (undef_name, hash, *ref, &val, + do_lookup_x (undef_name, new_hash, &old_hash, *ref, &val, undef_map->l_local_scope[0], 0, version, 0, NULL, type_class); |