glibc/elf/dl-deps.c
Ulrich Drepper 0a54e4010f Update.
1997-07-26 04:14  Ulrich Drepper  <drepper@cygnus.com>

	* elf/Makefile (distribute): Add genrtldtbl.awk.
	(before-compile): Add rtldtbl.h.
	(GAWK): New variable.
	(generated): Add trusted-dirs.h and rtldtbl.h.
	($(objpfx)rtldtbl.h): New rule.  File is needed by dl-load.c.
	* elf/dl-load.c: Rewrite.  Now use cache and look for shared
	objects in machine dependent directories.
	* elf/dl-object.c (_dl_new_object): Initialize l_rpath_dirs member.
	* elf/dl-support.c: Rename function to non_dynamic_init and add
	initialization for _dl_platform, _dl_platformlen, _dl_pagesize
	and call to initializer for search path.
	* elf/elf.h: Add AT_PLATFORM and AT_HWCAP.
	* elf/genrtldtbl.awk: New file.
	* elf/link.h: Add type definitions and declarations for search
	path cache.
	* elf/rtld.c: Add definitions of variables used for search path cache.
	* sysdeps/generic/dl-sysdep.c: Let auxiliary vector initialize
	_dl_platform.  Initialize _dl_pagesize early and use this value.
	* sysdeps/i386/dl-machine.h: Add code for _dl_platform handling.
	* sysdeps/mach/hurd/dl-sysdep.c: Initialize _dl_pagesize.
	* sysdeps/unix/sysv/linux/dl-sysdep.c: Use _dl_pagesize instead
	of calling getpagesize.

	* elf/dl-error.c (_dl_signal_error): Make message nicer.

	* nss/libnss_files.map: Fix typo.
	Reported by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>.

	* sysdeps/generic/strsep.c: Optimize case where separator set contains
	only one character.

	* sysdeps/libm-ieee754/s_ccosh.c: Correct sign of result for real
	== +-Inf.
	* sysdeps/libm-ieee754/s_ccoshf.c: Likewise.
	* sysdeps/libm-ieee754/s_ccoshl.c: Likewise.

1997-07-25 09:15  H.J. Lu  <hjl@gnu.ai.mit.edu>

	* sysdeps/sparc/udiv_qrnnd.S: Check PIC instead of __PIC__.
	* sysdeps/unix/sysv/linux/sparc/__sigtrampoline.S: Likewise.
	* sysdeps/unix/mips/sysdep.S: Likewise.
	* sysdeps/unix/sysv/linux/mips/clone.S: Likewise.

	* sysdeps/mips/bsd-_setjmp.S: Remove __PIC__ comment.
	* sysdeps/mips/bsd-setjmp.S: Likewise.

	* sysdeps/mips/dl-machine.h: Remove extra stuff.
	* sysdeps/mips/mips64/dl-machine.h: Likewise.

1997-07-25 18:55  Philip Blundell  <Philip.Blundell@pobox.com>

	* sysdeps/standalone/arm/sysdep.c: New file.

1997-07-25 13:25  Philip Blundell  <Philip.Blundell@pobox.com>

	* aout/Makefile: New file.
	* Makeconfig (binfmt-subdir): Assume a.out when not ELF.

	* sysdeps/generic/machine-gmon.h: Add warning about limitations of
	__builtin_return_address().
	* sysdeps/arm/machine-gmon.h: New file, use assembly to avoid
	above problem.

1997-07-25 16:24  H.J. Lu  <hjl@gnu.ai.mit.edu>

	* elf/dl-deps.c (_dl_map_object_deps): Fix a typo.

1997-07-22  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* math/libm-test.c (ccos_test, ccosh_test): Fix sign in some
	tests.

1997-07-24  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sunrpc/clnt_udp.c (clntudp_call): Rename cu_wait from timeout to
	not shadow the variable in the outer scope.
1997-07-26 02:33:30 +00:00

374 lines
11 KiB
C

/* Load the dependencies of a mapped object.
Copyright (C) 1996, 1997 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
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <link.h>
#include <errno.h>
#include <dlfcn.h>
#include <stdlib.h>
#include <assert.h>
/* Whether an shared object references one or more auxiliary objects
is signaled by the AUXTAG entry in l_info. */
#define AUXTAG (DT_NUM + DT_PROCNUM + DT_VERSIONTAGNUM \
+ DT_EXTRATAGIDX (DT_AUXILIARY))
/* When loading auxiliary objects we must ignore errors. It's ok if
an object is missing. */
struct openaux_args
{
/* The arguments to openaux. */
struct link_map *map;
int trace_mode;
const char *strtab;
const ElfW(Dyn) *d;
/* The return value of openaux. */
struct link_map *aux;
};
static void
openaux (void *a)
{
struct openaux_args *args = (struct openaux_args *) a;
args->aux = _dl_map_object (args->map, args->strtab + args->d->d_un.d_val,
(args->map->l_type == lt_executable
? lt_library : args->map->l_type),
args->trace_mode);
}
/* We use a very special kind of list to track the two kinds paths
through the list of loaded shared objects. We have to
- produce a flat list with unique members of all involved objects
- produce a flat list of all shared objects.
*/
struct list
{
int done; /* Nonzero if this map was processed. */
struct link_map *map; /* The data. */
struct list *unique; /* Elements for normal list. */
struct list *dup; /* Elements in complete list. */
};
void
_dl_map_object_deps (struct link_map *map,
struct link_map **preloads, unsigned int npreloads,
int trace_mode)
{
struct list known[1 + npreloads + 1];
struct list *runp, *head, *utail, *dtail;
unsigned int nlist, nduplist, i;
inline void preload (struct link_map *map)
{
known[nlist].done = 0;
known[nlist].map = map;
known[nlist].unique = &known[nlist + 1];
known[nlist].dup = &known[nlist + 1];
++nlist;
/* We use `l_reserved' as a mark bit to detect objects we have
already put in the search list and avoid adding duplicate
elements later in the list. */
map->l_reserved = 1;
}
/* No loaded object so far. */
nlist = 0;
/* First load MAP itself. */
preload (map);
/* Add the preloaded items after MAP but before any of its dependencies. */
for (i = 0; i < npreloads; ++i)
preload (preloads[i]);
/* Terminate the lists. */
known[nlist - 1].unique = NULL;
known[nlist - 1].dup = NULL;
/* Pointer to the first member of the unique and duplicate list. */
head = known;
/* Pointer to last unique object. */
utail = &known[nlist - 1];
/* Pointer to last loaded object. */
dtail = &known[nlist - 1];
/* Until now we have the same number of libraries in the normal and
the list with duplicates. */
nduplist = nlist;
/* Process each element of the search list, loading each of its
auxiliary objects and immediate dependencies. Auxiliary objects
will be added in the list before the object itself and
dependencies will be appended to the list as we step through it.
This produces a flat, ordered list that represents a
breadth-first search of the dependency tree.
The whole process is complicated by the fact that we better
should use alloca for the temporary list elements. But using
alloca means we cannot use recursive function calls. */
for (runp = known; runp; )
{
struct link_map *l = runp->map;
if (l->l_info[AUXTAG] || l->l_info[DT_NEEDED])
{
const char *strtab = ((void *) l->l_addr
+ l->l_info[DT_STRTAB]->d_un.d_ptr);
struct openaux_args args;
struct list *orig;
const ElfW(Dyn) *d;
/* Mark map as processed. */
runp->done = 1;
args.strtab = strtab;
args.map = l;
args.trace_mode = trace_mode;
orig = runp;
for (d = l->l_ld; d->d_tag != DT_NULL; ++d)
if (d->d_tag == DT_NEEDED)
{
/* Map in the needed object. */
struct link_map *dep
= _dl_map_object (l, strtab + d->d_un.d_val,
l->l_type == lt_executable ? lt_library :
l->l_type, trace_mode);
/* Allocate new entry. */
struct list *newp = alloca (sizeof (struct list));
/* Add it in any case to the duplicate list. */
newp->map = dep;
newp->dup = NULL;
dtail->dup = newp;
dtail = newp;
++nduplist;
if (dep->l_reserved)
/* This object is already in the search list we are
building. Don't add a duplicate pointer.
Release the reference just added by
_dl_map_object. */
--dep->l_opencount;
else
{
/* Append DEP to the unique list. */
newp->done = 0;
newp->unique = NULL;
utail->unique = newp;
utail = newp;
++nlist;
/* Set the mark bit that says it's already in the list. */
dep->l_reserved = 1;
}
}
else if (d->d_tag == DT_AUXILIARY)
{
char *errstring;
const char *objname;
/* Store the tag in the argument structure. */
args.d = d;
if (_dl_catch_error (&errstring, &objname, openaux, &args))
{
/* We are not interested in the error message. */
assert (errstring != NULL);
free (errstring);
}
else
{
/* The auxiliary object is actually available.
Incorporate the map in all the lists. */
/* Allocate new entry. This always has to be done. */
struct list *newp = alloca (sizeof (struct list));
/* Copy the content of the current entry over. */
memcpy (newp, orig, sizeof (*newp));
/* Initialize new entry. */
orig->done = 0;
orig->map = args.aux;
orig->dup = newp;
/* We must handle two situations here: the map is new,
so we must add it in all three lists. If the map
is already known, we have two further possibilities:
- if the object is before the current map in the
search list, we do nothing. It is already found
early
- if the object is after the current one, we must
move it just before the current map to make sure
the symbols are found early enough
*/
if (args.aux->l_reserved)
{
/* The object is already somewhere in the
list. Locate it first. */
struct list *late;
/* This object is already in the search list
we are building. Don't add a duplicate
pointer. Release the reference just added
by _dl_map_object. */
--args.aux->l_opencount;
for (late = orig; late->unique; late = late->unique)
if (late->unique->map == args.aux)
break;
if (late->unique)
{
/* The object is somewhere behind the current
position in the search path. We have to
move it to this earlier position. */
orig->unique = newp;
/* Now remove the later entry from the unique
list. */
late->unique = late->unique->unique;
/* We must move the earlier in the chain. */
if (args.aux->l_prev)
args.aux->l_prev->l_next = args.aux->l_next;
if (args.aux->l_next)
args.aux->l_next->l_prev = args.aux->l_prev;
args.aux->l_prev = newp->map->l_prev;
newp->map->l_prev = args.aux;
if (args.aux->l_prev != NULL)
args.aux->l_prev->l_next = args.aux;
args.aux->l_next = newp->map;
}
else
{
/* The object must be somewhere earlier in
the list. That's good, we only have to
insert an entry for the duplicate list. */
orig->unique = NULL; /* Never used. */
/* Now we have a problem. The element pointing
to ORIG in the unique list must point to
NEWP now. This is the only place where we
need this backreference and this situation
is really not that frequent. So we don't
use a double-linked list but instead search
for the preceding element. */
late = head;
while (late->unique != orig)
late = late->unique;
late->unique = newp;
}
}
else
{
/* This is easy. We just add the symbol right
here. */
orig->unique = newp;
++nlist;
/* Set the mark bit that says it's already in
the list. */
args.aux->l_reserved = 1;
/* The only problem is that in the double linked
list of all objects we don't have this new
object at the correct place. Correct this
here. */
if (args.aux->l_prev)
args.aux->l_prev->l_next = args.aux->l_next;
if (args.aux->l_next)
args.aux->l_next->l_prev = args.aux->l_prev;
args.aux->l_prev = newp->map->l_prev;
newp->map->l_prev = args.aux;
if (args.aux->l_prev != NULL)
args.aux->l_prev->l_next = args.aux;
args.aux->l_next = newp->map;
}
/* Move the tail pointers if necessary. */
if (orig == utail)
utail = newp;
if (orig == dtail)
dtail = newp;
/* Move on the insert point. */
orig = newp;
/* We always add an entry to the duplicate list. */
++nduplist;
}
}
}
else
/* Mark as processed. */
runp->done = 1;
/* If we have no auxiliary objects just go on to the next map. */
if (runp->done)
do
runp = runp->unique;
while (runp && runp->done);
}
/* Store the search list we built in the object. It will be used for
searches in the scope of this object. */
map->l_searchlist = malloc (nlist * sizeof (struct link_map *));
if (map->l_searchlist == NULL)
_dl_signal_error (ENOMEM, map->l_name,
"cannot allocate symbol search list");
map->l_nsearchlist = nlist;
for (nlist = 0, runp = head; runp; runp = runp->unique)
{
map->l_searchlist[nlist++] = runp->map;
/* Now clear all the mark bits we set in the objects on the search list
to avoid duplicates, so the next call starts fresh. */
runp->map->l_reserved = 0;
}
map->l_ndupsearchlist = nduplist;
if (nlist == nduplist)
map->l_dupsearchlist = map->l_searchlist;
else
{
map->l_dupsearchlist = malloc (nduplist * sizeof (struct link_map *));
if (map->l_dupsearchlist == NULL)
_dl_signal_error (ENOMEM, map->l_name,
"cannot allocate symbol search list");
for (nlist = 0, runp = head; runp; runp = runp->dup)
map->l_dupsearchlist[nlist++] = runp->map;
}
}