From a0e3f6f49caeaba666842f2999b57502437a1111 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Sat, 20 Feb 1999 21:12:26 +0000 Subject: Update. * elf/Makefile (distribute): Add do-lookup.h. * elf/do-lookup.h: New file. Split out from dl-lookup.c. * elf/dl-lookup.c: Move do_lookup function in separate file and include the file twice, for handling versioning and without it. --- elf/Makefile | 2 +- elf/dl-lookup.c | 191 +++++--------------------------------------------------- 2 files changed, 18 insertions(+), 175 deletions(-) (limited to 'elf') diff --git a/elf/Makefile b/elf/Makefile index ef5b831863..1e8d1a40fc 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -40,7 +40,7 @@ distribute = $(rtld-routines:=.c) dynamic-link.h do-rel.h dl-machine.h \ genrtldtbl.awk atomicity.h dl-procinfo.h ldsodefs.h \ dl-librecon.h interp.c sln.c dl-origin.h hp-timing.h \ testobj1.c testobj2.c testobj3.c testobj4.c testobj5.c \ - testobj6.c testobj1_1.c failobj.c + testobj6.c testobj1_1.c failobj.c do-lookup.h include ../Makeconfig diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c index de5ecf5d62..dba9243d21 100644 --- a/elf/dl-lookup.c +++ b/elf/dl-lookup.c @@ -60,173 +60,15 @@ struct sym_val unsigned long int _dl_num_relocations; -/* 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 inline int -do_lookup (const char *undef_name, unsigned long int hash, - const ElfW(Sym) *ref, struct sym_val *result, - struct r_scope_elem *scope, size_t i, const char *reference_name, - const struct r_found_version *version, struct link_map *skip, - int reloc_type) -{ - struct link_map **list = scope->r_list; - size_t n = scope->r_nlist; - struct link_map *map; +/* We have two different situations when looking up a simple: with or + without versioning. gcc is not able to optimize a single function + definition serving for both purposes so we define two functions. */ +#define VERSIONED 0 +#include "do-lookup.h" - for (; i < n; ++i) - { - const ElfW(Sym) *symtab; - const char *strtab; - const ElfW(Half) *verstab; - ElfW(Symndx) symidx; - int num_versions = 0; - const ElfW(Sym) *sym; - const ElfW(Sym) *versioned_sym = NULL; - - map = list[i]; - - /* Here come the extra test needed for `_dl_lookup_symbol_skip'. */ - if (skip != NULL && map == skip) - continue; - - /* Skip objects that could not be opened, which can occur in trace - mode. */ - if (map->l_opencount == 0) - continue; - - /* Don't search the executable when resolving a copy reloc. */ - if (elf_machine_lookup_noexec_p (reloc_type) - && map->l_type == lt_executable) - continue; - - /* Skip objects without symbol tables. */ - if (map->l_info[DT_SYMTAB] == NULL) - continue; - - /* Print some debugging info if wanted. */ - if (_dl_debug_symbols) - _dl_debug_message (1, "symbol=", undef_name, "; lookup in file=", - map->l_name[0] ? map->l_name : _dl_argv[0], - "\n", NULL); - - symtab = (const void *) map->l_info[DT_SYMTAB]->d_un.d_ptr; - strtab = (const void *) map->l_info[DT_STRTAB]->d_un.d_ptr; - verstab = map->l_versyms; - - /* Search the appropriate hash bucket in this object's symbol table - for a definition for the same symbol name. */ - for (symidx = map->l_buckets[hash % map->l_nbuckets]; - symidx != STN_UNDEF; - symidx = map->l_chain[symidx]) - { - sym = &symtab[symidx]; - - if (sym->st_value == 0 || /* No value. */ - (elf_machine_lookup_noplt_p (reloc_type) /* Reject PLT entry. */ - && sym->st_shndx == SHN_UNDEF)) - continue; - - if (ELFW(ST_TYPE) (sym->st_info) > STT_FUNC) - /* Ignore all but STT_NOTYPE, STT_OBJECT and STT_FUNC entries - since these are no code/data definitions. */ - continue; - - if (sym != ref && strcmp (strtab + sym->st_name, undef_name)) - /* Not the symbol we are looking for. */ - continue; - - if (version == NULL) - { - /* No specific version is selected. When the object - file also does not define a version we have a match. - Otherwise we accept the default version, or in case - there is only one version defined, this one version. */ - if (verstab != NULL) - { - ElfW(Half) ndx = verstab[symidx] & 0x7fff; - if (ndx > 2) /* map->l_versions[ndx].hash != 0) */ - { - /* Don't accept hidden symbols. */ - if ((verstab[symidx] & 0x8000) == 0 - && num_versions++ == 0) - /* No version so far. */ - versioned_sym = sym; - continue; - } - } - } - else - { - if (verstab == NULL) - { - /* We need a versioned system 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. */ - if (version->filename != NULL - && _dl_name_match_p (version->filename, map)) - return -2; - /* 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. */ - continue; - } - } - - /* There cannot be another entry for this symbol so stop here. */ - goto found_it; - } +#define VERSIONED 1 +#include "do-lookup.h" - /* 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 (ELFW(ST_BIND) (sym->st_info)) - { - case STB_GLOBAL: - /* Global definition. Just what we need. */ - result->s = sym; - result->m = map; - return 1; - case STB_WEAK: - /* Weak definition. Use this value if we don't find another. */ - if (! result->s) - { - result->s = sym; - result->m = map; - } - break; - 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 - && _dl_name_match_p (version->filename, map)) - return -1; - } - - /* We have not found anything until now. */ - return 0; -} /* Search loaded objects' symbol tables for a definition of the symbol UNDEF_NAME. */ @@ -247,7 +89,7 @@ _dl_lookup_symbol (const char *undef_name, const ElfW(Sym) **ref, /* Search the relevant loaded objects for a definition. */ for (scope = symbol_scope; *scope; ++scope) if (do_lookup (undef_name, hash, *ref, ¤t_value, - *scope, 0, reference_name, NULL, NULL, reloc_type)) + *scope, 0, reference_name, NULL, reloc_type)) break; if (current_value.s == NULL) @@ -301,10 +143,10 @@ _dl_lookup_symbol_skip (const char *undef_name, const ElfW(Sym) **ref, assert (i < (*scope)->r_nduplist); if (! do_lookup (undef_name, hash, *ref, ¤t_value, - *scope, i, reference_name, NULL, skip_map, 0)) + *scope, i, reference_name, skip_map, 0)) while (*++scope) if (do_lookup (undef_name, hash, *ref, ¤t_value, - *scope, 0, reference_name, NULL, skip_map, 0)) + *scope, 0, reference_name, skip_map, 0)) break; if (current_value.s == NULL) @@ -349,8 +191,9 @@ _dl_lookup_versioned_symbol (const char *undef_name, const ElfW(Sym) **ref, /* Search the relevant loaded objects for a definition. */ for (scope = symbol_scope; *scope; ++scope) { - int res = do_lookup (undef_name, hash, *ref, ¤t_value, - *scope, 0, reference_name, version, NULL, reloc_type); + int res = do_lookup_versioned (undef_name, hash, *ref, ¤t_value, + *scope, 0, reference_name, version, NULL, + reloc_type); if (res > 0) break; @@ -420,11 +263,11 @@ _dl_lookup_versioned_symbol_skip (const char *undef_name, for (i = 0; (*scope)->r_duplist[i] != skip_map; ++i) assert (i < (*scope)->r_nduplist); - if (! do_lookup (undef_name, hash, *ref, ¤t_value, - *scope, i, reference_name, version, skip_map, 0)) + if (! do_lookup_versioned (undef_name, hash, *ref, ¤t_value, + *scope, i, reference_name, version, skip_map, 0)) while (*++scope) - if (do_lookup (undef_name, hash, *ref, ¤t_value, - *scope, 0, reference_name, version, skip_map, 0)) + if (do_lookup_versioned (undef_name, hash, *ref, ¤t_value, *scope, + 0, reference_name, version, skip_map, 0)) break; if (current_value.s == NULL) -- cgit 1.4.1