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-rw-r--r--REORG.TODO/elf/dl-debug.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/REORG.TODO/elf/dl-debug.c b/REORG.TODO/elf/dl-debug.c
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+++ b/REORG.TODO/elf/dl-debug.c
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+/* Communicate dynamic linker state to the debugger at runtime.
+   Copyright (C) 1996-2017 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 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <ldsodefs.h>
+
+
+/* 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];
+
+/* 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 *
+internal_function
+_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns)
+{
+  struct r_debug *r;
+
+  if (ns == LM_ID_BASE)
+    r = &_r_debug;
+  else
+    r = &GL(dl_ns)[ns]._ns_debug;
+
+  if (r->r_map == NULL || ldbase != 0)
+    {
+      /* Tell the debugger where to find the map of loaded objects.  */
+      r->r_version = 1	/* R_DEBUG_VERSION XXX */;
+      r->r_ldbase = ldbase ?: _r_debug.r_ldbase;
+      r->r_map = (void *) GL(dl_ns)[ns]._ns_loaded;
+      r->r_brk = (ElfW(Addr)) &_dl_debug_state;
+    }
+
+  return r;
+}
+
+
+/* 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)
+{
+}
+rtld_hidden_def (_dl_debug_state)