X-Git-Url: http://git.ipfire.org/?a=blobdiff_plain;f=elf%2Fdl-debug.c;h=ef56de7a295656524bc918dbeed7d2cf9cf11d09;hb=HEAD;hp=e0bf1fbbc46d864cf62dfc3a25b0d85dc802d9a5;hpb=d0fc4041fec47665faff6ac1f51d71829f2dc30a;p=thirdparty%2Fglibc.git

diff --git a/elf/dl-debug.c b/elf/dl-debug.c
index e0bf1fbbc46..ef56de7a295 100644
--- a/elf/dl-debug.c
+++ b/elf/dl-debug.c
@@ -1,49 +1,109 @@
 /* Communicate dynamic linker state to the debugger at runtime.
-   Copyright (C) 1996, 1998 Free Software Foundation, Inc.
+   Copyright (C) 1996-2024 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.
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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.
+   Lesser 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.  */
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
 
-#include <elf/ldsodefs.h>
+#include <ldsodefs.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;
 
+/* These are the members in the public `struct link_map' type.
+   Sanity check that the internal type and the public type match.  */
+#define VERIFY_MEMBER(name) \
+  (offsetof (struct link_map_public, name) == offsetof (struct link_map, name))
+extern const int verify_link_map_members[(VERIFY_MEMBER (l_addr)
+					  && VERIFY_MEMBER (l_name)
+					  && VERIFY_MEMBER (l_ld)
+					  && VERIFY_MEMBER (l_next)
+					  && VERIFY_MEMBER (l_prev))
+					 ? 1 : -1];
 
-/* 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.  */
+/* Update the `r_map' member and return the address of `struct r_debug'
+   of the namespace NS. */
 
 struct r_debug *
-internal_function
-_dl_debug_initialize (ElfW(Addr) ldbase)
+_dl_debug_update (Lmid_t ns)
 {
-  if (_r_debug.r_brk == 0)
+  struct r_debug_extended *r;
+  if (ns == LM_ID_BASE)
+    r = &_r_debug_extended;
+  else
+    r = &GL(dl_ns)[ns]._ns_debug;
+  if (r->base.r_map == NULL)
+    atomic_store_release (&r->base.r_map,
+			  (void *) GL(dl_ns)[ns]._ns_loaded);
+  return &r->base;
+}
+
+/* Initialize _r_debug_extended for the namespace NS.  LDBASE is the
+   run-time load address of the dynamic linker, to be put in
+   _r_debug_extended.r_ldbase.  Return the address of _r_debug.  */
+
+struct r_debug *
+_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns)
+{
+  struct r_debug_extended *r, **pp = NULL;
+
+  if (ns == LM_ID_BASE)
+    {
+      r = &_r_debug_extended;
+      /* Initialize r_version to 1.  */
+      if (_r_debug_extended.base.r_version == 0)
+	_r_debug_extended.base.r_version = 1;
+    }
+  else if (DL_NNS > 1)
+    {
+      r = &GL(dl_ns)[ns]._ns_debug;
+      if (r->base.r_brk == 0)
+	{
+	  /* Add the new namespace to the linked list.  After a namespace
+	     is initialized, r_brk becomes non-zero.  A namespace becomes
+	     empty (r_map == NULL) when it is unused.  But it is never
+	     removed from the linked list.  */
+	  struct r_debug_extended *p;
+	  for (pp = &_r_debug_extended.r_next;
+	       (p = *pp) != NULL;
+	       pp = &p->r_next)
+	    ;
+
+	  r->base.r_version = 2;
+	}
+    }
+
+  if (r->base.r_brk == 0)
+    {
+      /* Tell the debugger where to find the map of loaded objects.
+	 This function is called from dlopen.  Initialize the namespace
+	 only once.  */
+      r->base.r_ldbase = ldbase ?: _r_debug_extended.base.r_ldbase;
+      r->base.r_brk = (ElfW(Addr)) &_dl_debug_state;
+      r->r_next = NULL;
+    }
+
+  if (r->base.r_map == NULL)
+    atomic_store_release (&r->base.r_map,
+			  (void *) GL(dl_ns)[ns]._ns_loaded);
+
+  if (pp != NULL)
     {
-      /* Tell the debugger where to find the map of loaded objects.  */
-      _r_debug.r_version = 1	/* R_DEBUG_VERSION XXX */;
-      _r_debug.r_ldbase = ldbase;
-      _r_debug.r_map = _dl_loaded;
-      _r_debug.r_brk = (ElfW(Addr)) &_dl_debug_state;
+      atomic_store_release (pp, r);
+      /* Bump r_version to 2 for the new namespace.  */
+      atomic_store_release (&_r_debug_extended.base.r_version, 2);
     }
 
-  return &_r_debug;
+  return &r->base;
 }
 
 
@@ -55,3 +115,4 @@ void
 _dl_debug_state (void)
 {
 }
+rtld_hidden_def (_dl_debug_state)