glibc/elf/dl-deps.c
Roland McGrath f68b86cc7b Tue Jun 4 18:57:57 1996 Roland McGrath <roland@delasyd.gnu.ai.mit.edu>
* elf/dladdr.c: Remove #include <setjmp.h>, we don't use it.

	* shlib-versions: Set libdl=2.

	* elf/dl-deps.c (_dl_map_object_deps): Use a linked list of alloca'd
 	elements and then scan it to fill the single malloc'd array, instead
 	of using realloc to grow the array in the first pass.  _dl_map_object
	may do some mallocs that break our stream of reallocs, and the minimal
	realloc can't handle that.

	* elf/dl-init.c (_dl_init_next): Take argument, link_map whose
 	searchlist describes the piece of the DT_NEEDED graph to be
 	initialized.
	* elf/link.h: Update prototype.
	* sysdeps/i386/dl-machine.h (RTLD_START): Pass _dl_loaded as argument
	to _dl_init_next.
	* sysdeps/m68k/dl-machine.h: Likewise.
	* elf/dl-deps.c (_dl_open): Pass new object as arg to _dl_init_next.

	* elf/link.h (struct link_map): Add `l_reserved' member, soaking up
	extra bits in last byte.
	* elf/dl-deps.c (_dl_map_object_deps): Use that for mark bit to avoid
	putting dup elts in search list.

	* elf/dlclose.c: Use MAP->l_searchlist to find deps to close.

	* elf/dlsym.c: Don't tweak linked list.  Scope array given to
	_dl_lookup_symbol does the right thing.
Tue Jun  4 02:25:44 1996  Roland McGrath  <roland@delasyd.gnu.ai.mit.edu>
1996-06-04 23:06:02 +00:00

125 lines
3.6 KiB
C

/* Load the dependencies of a mapped object.
Copyright (C) 1996 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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <link.h>
#include <errno.h>
#include <dlfcn.h>
#include <stdlib.h>
void
_dl_map_object_deps (struct link_map *map)
{
struct list
{
struct link_map *map;
struct list *next;
};
struct list head, *tailp, *scanp;
unsigned int nlist;
/* Start the search list with one element: MAP itself. */
head.map = map;
head.next = NULL;
nlist = 1;
/* Process each element of the search list, loading each of its immediate
dependencies and appending them to the list as we step through it.
This produces a flat, ordered list that represents a breadth-first
search of the dependency tree. */
for (scanp = tailp = &head; scanp; scanp = scanp->next)
{
struct link_map *l = scanp->map;
/* 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. */
l->l_reserved = 1;
if (l->l_info[DT_NEEDED])
{
const char *strtab
= ((void *) l->l_addr + l->l_info[DT_STRTAB]->d_un.d_ptr);
const Elf32_Dyn *d;
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);
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 search list. */
tailp->next = alloca (sizeof *tailp);
tailp = tailp->next;
tailp->map = dep;
tailp->next = NULL;
++nlist;
}
}
}
}
/* 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 *));
map->l_nsearchlist = nlist;
nlist = 0;
for (scanp = &head; scanp; scanp = scanp->next)
{
map->l_searchlist[nlist++] = scanp->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. */
scanp->map->l_reserved = 0;
}
}
struct link_map *
_dl_open (struct link_map *parent, const char *file, int mode)
{
struct link_map *new, *l;
Elf32_Addr init;
/* Load the named object. */
new = _dl_map_object (parent, file);
/* Load that object's dependencies. */
_dl_map_object_deps (new);
/* Relocate the objects loaded. */
for (l = new; l; l = l->l_next)
if (! l->l_relocated)
_dl_relocate_object (l, (mode & RTLD_BINDING_MASK) == RTLD_LAZY);
/* Run the initializer functions of new objects. */
while (init = _dl_init_next (new))
(*(void (*) (void)) init) ();
return new;
}