/* Communicate dynamic linker state to the debugger at runtime.

   Copyright (C) 1996-2018 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 *

_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)