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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)
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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;
 }