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authorUlrich Drepper <drepper@redhat.com>1996-11-20 03:45:51 +0000
committerUlrich Drepper <drepper@redhat.com>1996-11-20 03:45:51 +0000
commit84384f5b6aaa622236ada8c9a7ff51f40b91fc20 (patch)
treea44eb8cd85e2a868fa8cd24f8c9cf7fc7d0e7f8c /elf/dl-lookup.c
parentc44db1b1985cb3c41ea9cd76fc5dd60edd087842 (diff)
Wed Nov 20 02:04:11 1996 Ulrich Drepper <drepper@cygnus.com> * sysdeps/unix/sysv/linux/sigsuspend.c: Make sigsuspend a weak alias of __sigsuspend. * grp/grp.h: Correct comment about POSIX compliance. * pwd/pwd.h: Likewise. * login/utmp.h: Update copyright and pretty-print prototypes. * sysdeps/generic/paths.h: Add _PATH_LASTLOG, _PATH_UTMP and _PATH_WTMP from utmpbits.h. * sysdeps/unix/sysv/linux/paths.h: Likewise. * sysdeps/generic/utmpbits.h: Remove here. * sysdeps/gnu/utmpbits.h: Likewise. * misc/sys/uio.h: Place __BEGIN_DECLS correctly. Pretty-print prototypes. * sysdeps/unix/sysv/linux/sparc/clone.S: New file. Taken from LinuxThreads-0.5. Tue Nov 19 13:43:07 1996 Richard Henderson <rth@tamu.edu> * inet/ether_hton.c: Include <string.h>. * inet/ether_ntoh.c: Likewise. * inet/rexec.c: Get errno, index, getpass, getlogin from headers. * misc/search.h: Fix hcreate_r argument type (unsigned -> size_t). * misc/sys/cdefs.h: Change __long_double_t definition from typedef to define. Jim Nance reports problems building XEmacs otherwise. * resolv/gethnamaddr.c: Protect h_errno redefinition. * resolv/getnetnamadr.c: Likewise. * resolv/herror.c: Likewise. * sysdeps/generic/sigset.h (__SIGSETFN): Operator ## doesn't work with -traditional. Reported by Eric Youngdale. While we're at this, don't do error checking in the __ functions. This is consistent with the sysv4 definitions and seems Right. * signal/signal.h: Don't __OPTIMIZE__ sigops to __ versions. Add prototype for __sigsuspend. * sysdeps/posix/sigblock.c: Optimize sigmask <-> sigset_t conversions for sigset_t == unsigned long. De-ansidecl-ify. Reformat copyright. * sysdeps/posix/sigpause.c: Likewise. * sysdeps/posix/sigsetmask.c: Likewise. * sysdeps/posix/sigvec.c: Likewise. * sysdeps/posix/sigintr.c: Reformat copyright. * sysdeps/posix/signal.c: Check signal number out of range since __sigismember doesn't anymore. Reformat copyright. * sysdeps/posix/sigwait.c: Use __ versions of sigfillset, sigismember, sigdelset, sigaction, and sigsuspend. * stdlib/drand48-iter.c (__drand48_iterate): Cast state fragments to the wider type before shifting. * sysdeps/alpha/bsd-_setjmp.S: Silence assembler warning "$at used without .set noat" in profiling hook. * sysdeps/alpha/bsd-setjmp.S: Likewise. * sysdeps/alpha/htonl.S: Likewise. * sysdeps/alpha/htons.S: Likewise. * sysdeps/alpha/s_copysign.S: Likewise. * sysdeps/alpha/setjmp.S: Likewise. * sysdeps/alpha/stpcpy.S: Likewise. * sysdeps/alpha/strcat.S: Likewise. * sysdeps/alpha/strcpy.S: Likewise. * sysdeps/alpha/strncat.S: Likewise. * sysdeps/unix/sysv/linux/alpha/brk.S: Likewise. * sysdeps/unix/sysv/linux/alpha/clone.S: Likewise. * sysdeps/unix/sysv/linux/alpha/ieee_get_fp_control.S: Likewise. * sysdeps/unix/sysv/linux/alpha/ieee_set_fp_control.S: Likewise. * sysdeps/unix/sysv/linux/alpha/llseek.S: Likewise. * sysdeps/unix/sysv/linux/alpha/sigsuspend.S: Likewise. Rename function to __sigsuspend and add weak alias. * sysdeps/unix/sysv/linux/alpha/syscall.S: Likewise. Add missing END. * sysdeps/alpha/w_sqrt.S: Define _ERRNO_H so <errnos.h> defines EDOM. * sysdeps/unix/execve.S: Match PSEUDO_END symbol with the symbol SYSCALL__ actually generated. * sysdeps/unix/sysv/linux/errnos.h [_LIBC_REENTRANT]: Reflexively #define __set_errno, as several imported subsystems (eg. BIND) check that the symbol is defined. * sysdeps/unix/sysv/linux/getsysstats.c: Include <alloca.h>. * sysdeps/alpha/memcpy.S: Temporarily remove until I can find a bug that manifests in GCC. Tue Nov 19 11:10:05 1996 Thomas Bushnell, n/BSG <thomas@gnu.ai.mit.edu> * sysdeps/posix/writev.c (writev): COUNT parm is now int. * sysdeps/posix/readv.c (readv): Likewise. Tue Nov 19 15:28:29 1996 Ulrich Drepper <drepper@cygnus.com> * nss/nss_dns/dns-network.c: Change return type of all functions to enum nss_status. Reported by NIIBE Yutaka. * nss/nss_dns/dns-host.c: Update copyright. Fri Nov 15 20:16:38 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * config.make.in: Remove definition of top_absdir. * configure.in: Likewise. Use $(..) instead. * Makerules (make-link): Use $(..) to find rellns-sh script. Sat Nov 16 15:52:29 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * manual/nss.texi (Name Service Switch): Fix reference to `frobnicate'. Fri Nov 15 22:08:33 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/unix/sysv/linux/Makefile (sysdep_headers): Add sys/mtio.h. Mon Nov 18 05:51:13 1996 Ulrich Drepper <drepper@cygnus.com> * sysdeps/generic/waitstatus.h (__WIFSIGNALED): Rename local variable from __stat to __status to prevent shadowing. * sunrpc/rpc/clnt.h (clntudp_create, clntudp_bufcreate): Likewise for parameter __wait. Reported by NIIBE Yutaka. Mon Nov 18 02:05:38 1996 Ulrich Drepper <drepper@cygnus.com> * misc/regexp.c: New file. Implementation of obsolete interface to regular expression matcher (required in XPG4.2). * misc/regexp.h: New file. Header for above. * misc/Makefile (headers): Add regexp.h. (routines): Add regexp.c. Update copyright. Sun Nov 17 21:50:24 1996 Andreas Jaeger <aj@arthur.pfalz.de> * stdlib/tst-strtod.c (main): Add arguments for main. * stdlib/tst-strtol.c (main): Likewise. Sun Nov 17 21:15:05 1996 Ulrich Drepper <drepper@cygnus.com> * configure.in: Substitute libc_cv_slibdir and libc_cv_sysconfdir in output files. * sysdepes/unix/sysv/linux/configure: Define libc_cv_slibdir to /lib and sysconfdir to /etc if $prefix is /usr. * config.make.in: Add slibdir, sysconfdir and BASH to be replaced. * elf/Makefile ($(objpfx)ldd): Install ldd.bash.in if $(have-bash2) is yes. * elf/ldd.bash.in: Add copyright and various cleanups. * elf/ldd.sh.in: Likewise. Implement RTLD_NEXT. * elf/dlfcn.h: Define RTLD_NEXT. * elf/dl-deps.c: Build second searchlist which contains duplicates. * elf/dl-lookup.c (_dl_lookup_symbol_skip): New function. Used for RTLD_NEXT lookup. Rewrite _dl_lookup_symbol to put common parts for both lookup functions in a separate function. * elf/dlsym.c: Handle RTLD_NEXT by calling _dl_lookup_symbol_skip. * elf/link.h (struct link_map): Add l_dupsearchlist and l_ndupsearchlist. Add prototype for _dl_lookup_symbol_skip. * sunrpc/Makefile (rpcsvc): Add rusers. * sunrpc/rpcsvc/rnusers.x: Remove. Obsolteted by rusers.x. * sunrpc/rpcsvc/rusers.x: New file. Sun Nov 17 04:24:35 1996 Ulrich Drepper <drepper@cygnus.com> * stdio-common/vfprintf.c [USE_IN_LIBIO] (buffered_vfprintf): Call __libc_lock_init for local lock. Reported by a sun <asun@zoology.washington.edu>. [!USE_IN_LIBIO] (PAD): Optimize a bit.
Diffstat (limited to 'elf/dl-lookup.c')
-rw-r--r--elf/dl-lookup.c211
1 files changed, 137 insertions, 74 deletions
diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c
index f35bbbe967..717ac83f7a 100644
--- a/elf/dl-lookup.c
+++ b/elf/dl-lookup.c
@@ -23,6 +23,13 @@
#include <string.h>
+struct sym_val
+ {
+ ElfW(Addr) a;
+ const ElfW(Sym) *s;
+ };
+
+
/* This is the hashing function specified by the ELF ABI. */
static inline unsigned
_dl_elf_hash (const char *name)
@@ -44,6 +51,90 @@ _dl_elf_hash (const char *name)
return hash;
}
+
+/* Inner part of the lookup functions. */
+static inline ElfW(Addr)
+do_lookup (const char *undef_name, unsigned long int hash,
+ const ElfW(Sym) **ref, struct sym_val *result,
+ struct link_map *list[], size_t i, size_t n,
+ const char *reference_name, struct link_map *skip, int flags)
+{
+ struct link_map *map;
+
+ for (; i < n; ++i)
+ {
+ const ElfW(Sym) *symtab;
+ const char *strtab;
+ ElfW(Symndx) symidx;
+
+ map = list[i];
+
+ /* Here come the extra test needed for `_dl_lookup_symbol_skip'. */
+ if (skip != NULL && map == skip)
+ continue;
+
+ /* Don't search the executable when resolving a copy reloc. */
+ if (flags & DL_LOOKUP_NOEXEC && map->l_type == lt_executable)
+ continue;
+
+ symtab = ((void *) map->l_addr + map->l_info[DT_SYMTAB]->d_un.d_ptr);
+ strtab = ((void *) map->l_addr + map->l_info[DT_STRTAB]->d_un.d_ptr);
+
+ /* 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])
+ {
+ const ElfW(Sym) *sym = &symtab[symidx];
+
+ if (sym->st_value == 0 || /* No value. */
+ ((flags & DL_LOOKUP_NOPLT) != 0 /* Reject PLT entry. */
+ && sym->st_shndx == SHN_UNDEF))
+ continue;
+
+ switch (ELFW(ST_TYPE) (sym->st_info))
+ {
+ case STT_NOTYPE:
+ case STT_FUNC:
+ case STT_OBJECT:
+ break;
+ default:
+ /* Not a code/data definition. */
+ continue;
+ }
+
+ if (sym != *ref && strcmp (strtab + sym->st_name, undef_name))
+ /* Not the symbol we are looking for. */
+ continue;
+
+ switch (ELFW(ST_BIND) (sym->st_info))
+ {
+ case STB_GLOBAL:
+ /* Global definition. Just what we need. */
+ result->s = sym;
+ result->a = map->l_addr;
+ return 1;
+ case STB_WEAK:
+ /* Weak definition. Use this value if we don't find
+ another. */
+ if (! result->s)
+ {
+ result->s = sym;
+ result->a = map->l_addr;
+ }
+ break;
+ default:
+ /* Local symbols are ignored. */
+ break;
+ }
+ }
+ }
+
+ /* We have not found anything until now. */
+ return 0;
+}
+
/* Search loaded objects' symbol tables for a definition of the symbol
UNDEF_NAME. FLAGS is a set of flags. If DL_LOOKUP_NOEXEC is set,
then don't search the executable for a definition; this used for
@@ -57,82 +148,17 @@ _dl_lookup_symbol (const char *undef_name, const ElfW(Sym) **ref,
int flags)
{
const unsigned long int hash = _dl_elf_hash (undef_name);
- struct
- {
- ElfW(Addr) a;
- const ElfW(Sym) *s;
- } weak_value = { 0, NULL };
- size_t i;
- struct link_map **scope, *map;
+ struct sym_val current_value = { 0, NULL };
+ struct link_map **scope;
/* Search the relevant loaded objects for a definition. */
for (scope = symbol_scope; *scope; ++scope)
- for (i = 0; i < (*scope)->l_nsearchlist; ++i)
- {
- const ElfW(Sym) *symtab;
- const char *strtab;
- ElfW(Symndx) symidx;
-
- map = (*scope)->l_searchlist[i];
-
- /* Don't search the executable when resolving a copy reloc. */
- if (flags & DL_LOOKUP_NOEXEC && map->l_type == lt_executable)
- continue;
-
- symtab = ((void *) map->l_addr + map->l_info[DT_SYMTAB]->d_un.d_ptr);
- strtab = ((void *) map->l_addr + map->l_info[DT_STRTAB]->d_un.d_ptr);
-
- /* 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])
- {
- const ElfW(Sym) *sym = &symtab[symidx];
-
- if (sym->st_value == 0 || /* No value. */
- ((flags & DL_LOOKUP_NOPLT) != 0 /* Reject PLT entry. */
- && sym->st_shndx == SHN_UNDEF))
- continue;
-
- switch (ELFW(ST_TYPE) (sym->st_info))
- {
- case STT_NOTYPE:
- case STT_FUNC:
- case STT_OBJECT:
- break;
- default:
- /* Not a code/data definition. */
- continue;
- }
-
- if (sym != *ref && strcmp (strtab + sym->st_name, undef_name))
- /* Not the symbol we are looking for. */
- continue;
+ if (do_lookup (undef_name, hash, ref, &current_value,
+ (*scope)->l_searchlist, 0, (*scope)->l_nsearchlist,
+ reference_name, NULL, flags))
+ break;
- switch (ELFW(ST_BIND) (sym->st_info))
- {
- case STB_GLOBAL:
- /* Global definition. Just what we need. */
- *ref = sym;
- return map->l_addr;
- case STB_WEAK:
- /* Weak definition. Use this value if we don't find
- another. */
- if (! weak_value.s)
- {
- weak_value.s = sym;
- weak_value.a = map->l_addr;
- }
- break;
- default:
- /* Local symbols are ignored. */
- break;
- }
- }
- }
-
- if (weak_value.s == NULL &&
+ if (current_value.s == NULL &&
(*ref == NULL || ELFW(ST_BIND) ((*ref)->st_info) != STB_WEAK))
{
/* We could find no value for a strong reference. */
@@ -144,8 +170,45 @@ _dl_lookup_symbol (const char *undef_name, const ElfW(Sym) **ref,
_dl_signal_error (0, reference_name, buf);
}
- *ref = weak_value.s;
- return weak_value.a;
+ *ref = current_value.s;
+ return current_value.a;
+}
+
+
+/* This function is nearly the same as `_dl_lookup_symbol' but it
+ skips in the first list all objects until SKIP_MAP is found. I.e.,
+ it only considers objects which were loaded after the described
+ object. If there are more search lists the object described by
+ SKIP_MAP is only skipped. */
+ElfW(Addr)
+_dl_lookup_symbol_skip (const char *undef_name, const ElfW(Sym) **ref,
+ struct link_map *symbol_scope[],
+ const char *reference_name,
+ struct link_map *skip_map,
+ int flags)
+{
+ int found_entry = 0;
+ const unsigned long int hash = _dl_elf_hash (undef_name);
+ struct sym_val current_value = { 0, NULL };
+ struct link_map **scope;
+ size_t i;
+
+ /* Search the relevant loaded objects for a definition. */
+ scope = symbol_scope;
+ for (i = 0; (*scope)->l_dupsearchlist[i] != skip_map; ++i)
+ assert (i < (*scope)->l_ndupsearchlist);
+
+ if (! do_lookup (undef_name, hash, ref, &current_value,
+ (*scope)->l_dupsearchlist, i, (*scope)->l_ndupsearchlist,
+ reference_name, skip_map, flags))
+ while (*++scope)
+ if (do_lookup (undef_name, hash, ref, &current_value,
+ (*scope)->l_dupsearchlist, 0, (*scope)->l_ndupsearchlist,
+ reference_name, skip_map, flags))
+ break;
+
+ *ref = current_value.s;
+ return current_value.a;
}