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-rw-r--r--elf/Makefile2
-rw-r--r--elf/dl-close.c8
-rw-r--r--elf/dl-debug.c56
-rw-r--r--elf/dl-init.c5
-rw-r--r--elf/dl-lookup.c3
-rw-r--r--elf/dl-open.c15
-rw-r--r--elf/link.h10
-rw-r--r--elf/rtld.c34
8 files changed, 108 insertions, 25 deletions
diff --git a/elf/Makefile b/elf/Makefile
index 07ffbd8788..be7604de8e 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -26,7 +26,7 @@ routines = $(dl-routines) dl-open dl-close dl-symbol dl-support
# The core dynamic linking functions are in libc for the static and
# profiled libraries.
dl-routines = $(addprefix dl-,load lookup object reloc deps \
- runtime error init fini)
+ runtime error init fini debug)
# But they are absent from the shared libc, because that code is in ld.so.
elide-routines.so = $(dl-routines) dl-support
diff --git a/elf/dl-close.c b/elf/dl-close.c
index 70d7ab4083..184d38298e 100644
--- a/elf/dl-close.c
+++ b/elf/dl-close.c
@@ -41,6 +41,10 @@ _dl_close (struct link_map *map)
/* There are still references to this object. Do nothing more. */
return;
+ /* Notify the debugger we are about to remove some loaded objects. */
+ _r_debug.r_state = RT_DELETE;
+ _dl_debug_state ();
+
list = map->l_searchlist;
/* The search list contains a counted reference to each object it
@@ -105,4 +109,8 @@ _dl_close (struct link_map *map)
}
free (list);
+
+ /* Notify the debugger those objects are finalized and gone. */
+ _r_debug.r_state = RT_CONSISTENT;
+ _dl_debug_state ();
}
diff --git a/elf/dl-debug.c b/elf/dl-debug.c
new file mode 100644
index 0000000000..861e0019e8
--- /dev/null
+++ b/elf/dl-debug.c
@@ -0,0 +1,56 @@
+/* Communicate dynamic linker state to the debugger at runtime.
+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>
+
+/* This structure communicates dl state to the debugger. The debugger
+ normally finds it via the DT_DEBUG entry in the dynamic section, but in
+ a statically-linked program there is no dynamic section for the debugger
+ to examine and it looks for this particular symbol name. */
+struct r_debug _r_debug;
+
+
+/* Initialize _r_debug if it has not already been done. The argument is
+ the run-time load address of the dynamic linker, to be put in
+ _r_debug.r_ldbase. Returns the address of _r_debug. */
+
+struct r_debug *
+_dl_debug_initialize (ElfW(Addr) ldbase)
+{
+ if (_r_debug.r_brk == 0)
+ {
+ /* Tell the debugger where to find the map of loaded objects. */
+ _r_debug.r_version = 1 /* R_DEBUG_VERSION XXX */;
+ _r_debug.r_ldbase = _dl_rtld_map.l_addr; /* Record our load address. */
+ _r_debug.r_map = _dl_loaded;
+ _r_debug.r_brk = (ElfW(Addr)) &_dl_debug_state;
+ }
+
+ return &_r_debug;
+}
+
+
+/* This function exists solely to have a breakpoint set on it by the
+ debugger. The debugger is supposed to find this function's address by
+ examining the r_brk member of struct r_debug, but GDB 4.15 in fact looks
+ for this particular symbol name in the PT_INTERP file. */
+void
+_dl_debug_state (void)
+{
+}
diff --git a/elf/dl-init.c b/elf/dl-init.c
index 66ef83e28b..6259c35235 100644
--- a/elf/dl-init.c
+++ b/elf/dl-init.c
@@ -65,5 +65,10 @@ _dl_init_next (struct link_map *map)
l->l_init_called = 1;
}
+
+ /* Notify the debugger all new objects are now ready to go. */
+ _r_debug.r_state = RT_CONSISTENT;
+ _dl_debug_state ();
+
return 0;
}
diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c
index bbccbc01ef..7ceffa23e1 100644
--- a/elf/dl-lookup.c
+++ b/elf/dl-lookup.c
@@ -129,7 +129,8 @@ _dl_lookup_symbol (const char *undef_name, const ElfW(Sym) **ref,
}
}
- if (weak_value.s == NULL && ELFW(ST_BIND) ((*ref)->st_info) != STB_WEAK)
+ if (weak_value.s == NULL &&
+ !*ref || ELFW(ST_BIND) ((*ref)->st_info) != STB_WEAK)
{
/* We could find no value for a strong reference. */
const char msg[] = "undefined symbol: ";
diff --git a/elf/dl-open.c b/elf/dl-open.c
index 9389303b90..373d32dd79 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -29,6 +29,7 @@ _dl_open (struct link_map *parent, const char *file, int mode)
{
struct link_map *new, *l;
ElfW(Addr) init;
+ struct r_debug *r;
/* Load the named object. */
@@ -47,7 +48,7 @@ _dl_open (struct link_map *parent, const char *file, int mode)
l = new;
while (l->l_next)
l = l->l_next;
- do
+ while (1)
{
if (! l->l_relocated)
{
@@ -56,8 +57,10 @@ _dl_open (struct link_map *parent, const char *file, int mode)
*_dl_global_scope_end = NULL;
}
+ if (l == new)
+ break;
l = l->l_prev;
- } while (l != new);
+ }
new->l_global = (mode & RTLD_GLOBAL);
if (new->l_global)
@@ -108,6 +111,14 @@ _dl_open (struct link_map *parent, const char *file, int mode)
}
}
+
+ /* Notify the debugger we have added some objects. We need to call
+ _dl_debug_initialize in a static program in case dynamic linking has
+ not been used before. */
+ r = _dl_debug_initialize (0);
+ r->r_state = RT_ADD;
+ _dl_debug_state ();
+
/* Run the initializer functions of new objects. */
while (init = _dl_init_next (new))
(*(void (*) (void)) init) ();
diff --git a/elf/link.h b/elf/link.h
index 6910445095..f43ec411f8 100644
--- a/elf/link.h
+++ b/elf/link.h
@@ -62,6 +62,9 @@ struct r_debug
ElfW(Addr) r_ldbase; /* Base address the linker is loaded at. */
};
+/* This is the instance of that structure used by the dynamic linker. */
+extern struct r_debug _r_debug;
+
/* This symbol refers to the "dynamic structure" in the `.dynamic' section
of whatever module refers to `_DYNAMIC'. So, to find its own
`struct r_debug', a program could do:
@@ -291,7 +294,12 @@ extern void _dl_fini (void);
any shared object mappings. The `r_state' member of `struct r_debug'
says what change is taking place. This function's address is
the value of the `r_brk' member. */
-extern void _dl_r_debug_state (void);
+extern void _dl_debug_state (void);
+
+/* Initialize `struct r_debug' if it has not already been done. The
+ argument is the run-time load address of the dynamic linker, to be put
+ in the `r_ldbase' member. Returns the address of the structure. */
+extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase);
#endif /* link.h */
diff --git a/elf/rtld.c b/elf/rtld.c
index c9ddfb5c63..7befc0a82f 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -46,8 +46,6 @@ int _dl_argc;
char **_dl_argv;
const char *_dl_rpath;
-struct r_debug _dl_r_debug;
-
static void dl_main (const ElfW(Phdr) *phdr,
ElfW(Half) phent,
ElfW(Addr) *user_entry);
@@ -229,12 +227,6 @@ of this helper program; chances are you did not intend to run this program.\n",
/* Set up our cache of pointers into the hash table. */
_dl_setup_hash (l);
- if (l->l_info[DT_DEBUG])
- /* There is a DT_DEBUG entry in the dynamic section. Fill it in
- with the run-time address of the r_debug structure, which we
- will set up later to communicate with the debugger. */
- l->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) &_dl_r_debug;
-
/* Put the link_map for ourselves on the chain so it can be found by
name. */
_dl_rtld_map.l_name = (char *) _dl_rtld_map.l_libname = interpreter_name;
@@ -343,11 +335,20 @@ of this helper program; chances are you did not intend to run this program.\n",
_dl_relocate_object (&_dl_rtld_map, &_dl_default_scope[2], 0);
}
- /* Tell the debugger where to find the map of loaded objects. */
- _dl_r_debug.r_version = 1 /* R_DEBUG_VERSION XXX */;
- _dl_r_debug.r_ldbase = _dl_rtld_map.l_addr; /* Record our load address. */
- _dl_r_debug.r_map = _dl_loaded;
- _dl_r_debug.r_brk = (ElfW(Addr)) &_dl_r_debug_state;
+ {
+ /* Initialize _r_debug. */
+ struct r_debug *r = _dl_debug_initialize (_dl_rtld_map.l_addr);
+
+ l = _dl_loaded;
+ if (l->l_info[DT_DEBUG])
+ /* There is a DT_DEBUG entry in the dynamic section. Fill it in
+ with the run-time address of the r_debug structure */
+ l->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r;
+
+ /* Notify the debugger that all objects are now mapped in. */
+ r->r_state = RT_ADD;
+ _dl_debug_state ();
+ }
if (_dl_rtld_map.l_info[DT_INIT])
{
@@ -365,10 +366,3 @@ of this helper program; chances are you did not intend to run this program.\n",
/* Once we return, _dl_sysdep_start will invoke
the DT_INIT functions and then *USER_ENTRY. */
}
-
-/* This function exists solely to have a breakpoint set on it by the
- debugger. */
-void
-_dl_r_debug_state (void)
-{
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-08 22:59:45 +0000