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authorUlrich Drepper <drepper@redhat.com>1999-02-20 21:12:26 +0000
committerUlrich Drepper <drepper@redhat.com>1999-02-20 21:12:26 +0000
commita0e3f6f49caeaba666842f2999b57502437a1111 (patch)
tree782e8d3d8053dfd6c29dab0eb2ea6208a996e713 /elf/dl-lookup.c
parent7796221a03774b61f979e8bb137d40509fd8a1c3 (diff)
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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.
Diffstat (limited to 'elf/dl-lookup.c')
-rw-r--r--elf/dl-lookup.c191
1 files changed, 17 insertions, 174 deletions
diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c
index de5ecf5..dba9243 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, &current_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, &current_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, &current_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, &current_value,
- *scope, 0, reference_name, version, NULL, reloc_type);
+ int res = do_lookup_versioned (undef_name, hash, *ref, &current_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, &current_value,
- *scope, i, reference_name, version, skip_map, 0))
+ if (! do_lookup_versioned (undef_name, hash, *ref, &current_value,
+ *scope, i, reference_name, version, skip_map, 0))
while (*++scope)
- if (do_lookup (undef_name, hash, *ref, &current_value,
- *scope, 0, reference_name, version, skip_map, 0))
+ if (do_lookup_versioned (undef_name, hash, *ref, &current_value, *scope,
+ 0, reference_name, version, skip_map, 0))
break;
if (current_value.s == NULL)