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[!VERSIONED]: Add new parameter flags. Use it to check whether the caller

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prefers getting the most recent version of a symbol of the earliest version.
This commit is contained in:
Ulrich Drepper 2002-04-13 16:02:53 +00:00
parent 79b44ca788
commit 364793eb07
1 changed files with 25 additions and 10 deletions
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35
elf/do-lookup.h
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@ -1,5 +1,5 @@
/* Look up a symbol in the loaded objects.
Copyright (C) 1995,96,97,98,99,2000,2001 Free Software Foundation, Inc.
Copyright (C) 1995,96,97,98,99,2000,2001,2002 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
@ -19,10 +19,10 @@
#if VERSIONED
# define FCT do_lookup_versioned
# define ARG const struct r_found_version *const version,
# define ARG const struct r_found_version *const version
#else
# define FCT do_lookup
# define ARG
# define ARG int flags
#endif
/* Inner part of the lookup functions. We return a value > 0 if we
@ -30,7 +30,7 @@
something bad happened. */
static inline int
FCT (const char *undef_name, unsigned long int hash, const ElfW(Sym) *ref,
struct sym_val *result, struct r_scope_elem *scope, size_t i, ARG
struct sym_val *result, struct r_scope_elem *scope, size_t i, ARG,
struct link_map *skip, int type_class)
{
struct link_map **list = scope->r_list;
@ -121,19 +121,34 @@ FCT (const char *undef_name, unsigned long int hash, const ElfW(Sym) *ref,
continue;
}
#else
/* 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. */
/* 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)
{
ElfW(Half) ndx = verstab[symidx] & 0x7fff;
if (ndx >= 2) /* map->l_versions[ndx].hash != 0) */
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;
continue;
}
}