/* Debug logging for the symbol file functions for the GNU debugger, GDB.

   Copyright (C) 2013 Free Software Foundation, Inc.

   Contributed by Cygnus Support, using pieces from other GDB modules.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* Note: Be careful with functions that can throw errors.
   We want to see a logging message regardless of whether an error was thrown.
   This typically means printing a message before calling the real function
   and then if the function returns a result printing a message after it
   returns.  */

#include "defs.h"
#include "gdbcmd.h"
#include "objfiles.h"
#include "observer.h"
#include "source.h"
#include "symtab.h"
#include "symfile.h"

/* We need to save a pointer to the real symbol functions.
   Plus, the debug versions are malloc'd because we have to NULL out the
   ones that are NULL in the real copy.  */

struct debug_sym_fns_data
{
  const struct sym_fns *real_sf;
  struct sym_fns debug_sf;
};

/* We need to record a pointer to the real set of functions for each
   objfile.  */
static const struct objfile_data *symfile_debug_objfile_data_key;

/* If non-zero all calls to the symfile functions are logged.  */
static int debug_symfile = 0;

/* Return non-zero if symfile debug logging is installed.  */

static int
symfile_debug_installed (struct objfile *objfile)
{
  return (objfile->sf != NULL
	  && objfile_data (objfile, symfile_debug_objfile_data_key) != NULL);
}

/* Utility to return the name to print for OBJFILE.  */

static const char *
debug_objfile_name (const struct objfile *objfile)
{
  return lbasename (objfile->original_name);
}

/* Utility return the name to print for SYMTAB.  */

static const char *
debug_symtab_name (struct symtab *symtab)
{
  return symtab_to_filename_for_display (symtab);
}

/* Debugging version of struct quick_symbol_functions.  */

static int
debug_qf_has_symbols (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  int retval;

  retval = debug_data->real_sf->qf->has_symbols (objfile);

  fprintf_filtered (gdb_stdlog, "qf->has_symbols (%s) = %d\n",
		    debug_objfile_name (objfile), retval);

  return retval;
}

static struct symtab *
debug_qf_find_last_source_symtab (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  struct symtab *retval;

  fprintf_filtered (gdb_stdlog, "qf->find_last_source_symtab (%s)\n",
		    debug_objfile_name (objfile));

  retval = debug_data->real_sf->qf->find_last_source_symtab (objfile);

  fprintf_filtered (gdb_stdlog, "qf->find_last_source_symtab (...) = %s\n",
		    retval ? debug_symtab_name (retval) : "NULL");

  return retval;
}

static void
debug_qf_forget_cached_source_info (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "qf->forget_cached_source_info (%s)\n",
		    debug_objfile_name (objfile));

  debug_data->real_sf->qf->forget_cached_source_info (objfile);
}

static int
debug_qf_map_symtabs_matching_filename (struct objfile *objfile,
					const char *name,
					const char *real_path,
					int (*callback) (struct symtab *,
							 void *),
					void *data)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  int retval;

  fprintf_filtered (gdb_stdlog,
		    "qf->map_symtabs_matching_filename (%s, \"%s\", \"%s\", %s, %s)\n",
		    debug_objfile_name (objfile), name,
		    real_path ? real_path : NULL,
		    host_address_to_string (callback),
		    host_address_to_string (data));

  retval = debug_data->real_sf->qf->map_symtabs_matching_filename
    (objfile, name, real_path, callback, data);

  fprintf_filtered (gdb_stdlog,
		    "qf->map_symtabs_matching_filename (...) = %d\n",
		    retval);

  return retval;
}

static struct symtab *
debug_qf_lookup_symbol (struct objfile *objfile, int kind, const char *name,
			domain_enum domain)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  struct symtab *retval;

  fprintf_filtered (gdb_stdlog,
		    "qf->lookup_symbol (%s, %d, \"%s\", %s)\n",
		    debug_objfile_name (objfile), kind, name,
		    domain_name (domain));

  retval = debug_data->real_sf->qf->lookup_symbol (objfile, kind, name,
						   domain);

  fprintf_filtered (gdb_stdlog, "qf->lookup_symbol (...) = %s\n",
		    retval ? debug_symtab_name (retval) : "NULL");

  return retval;
}

static void
debug_qf_print_stats (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "qf->print_stats (%s)\n",
		    debug_objfile_name (objfile));

  debug_data->real_sf->qf->print_stats (objfile);
}

static void
debug_qf_dump (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "qf->dump (%s)\n",
		    debug_objfile_name (objfile));

  debug_data->real_sf->qf->dump (objfile);
}

static void
debug_qf_relocate (struct objfile *objfile,
		   const struct section_offsets *new_offsets,
		   const struct section_offsets *delta)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "qf->relocate (%s, %s, %s)\n",
		    debug_objfile_name (objfile),
		    host_address_to_string (new_offsets),
		    host_address_to_string (delta));

  debug_data->real_sf->qf->relocate (objfile, new_offsets, delta);
}

static void
debug_qf_expand_symtabs_for_function (struct objfile *objfile,
				      const char *func_name)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog,
		    "qf->expand_symtabs_for_function (%s, \"%s\")\n",
		    debug_objfile_name (objfile), func_name);

  debug_data->real_sf->qf->expand_symtabs_for_function (objfile, func_name);
}

static void
debug_qf_expand_all_symtabs (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "qf->expand_all_symtabs (%s)\n",
		    debug_objfile_name (objfile));

  debug_data->real_sf->qf->expand_all_symtabs (objfile);
}

static void
debug_qf_expand_symtabs_with_fullname (struct objfile *objfile,
				       const char *fullname)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog,
		    "qf->expand_symtabs_with_fullname (%s, \"%s\")\n",
		    debug_objfile_name (objfile), fullname);

  debug_data->real_sf->qf->expand_symtabs_with_fullname (objfile, fullname);
}

static void
debug_qf_map_matching_symbols (struct objfile *objfile,
			       const char *name, domain_enum namespace,
			       int global,
			       int (*callback) (struct block *,
						struct symbol *, void *),
			       void *data,
			       symbol_compare_ftype *match,
			       symbol_compare_ftype *ordered_compare)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog,
		    "qf->map_matching_symbols (%s, \"%s\", %s, %d, %s, %s, %s, %s)\n",
		    debug_objfile_name (objfile), name,
		    domain_name (namespace), global,
		    host_address_to_string (callback),
		    host_address_to_string (data),
		    host_address_to_string (match),
		    host_address_to_string (ordered_compare));

  debug_data->real_sf->qf->map_matching_symbols (objfile, name,
						 namespace, global,
						 callback, data,
						 match,
						 ordered_compare);
}

static void
debug_qf_expand_symtabs_matching (struct objfile *objfile,
				  int (*file_matcher) (const char *, void *,
						       int basenames),
				  int (*name_matcher) (const char *, void *),
				  enum search_domain kind,
				  void *data)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog,
		    "qf->expand_symtabs_matching (%s, %s, %s, %s, %s)\n",
		    debug_objfile_name (objfile),
		    host_address_to_string (file_matcher),
		    host_address_to_string (name_matcher),
		    search_domain_name (kind),
		    host_address_to_string (data));

  debug_data->real_sf->qf->expand_symtabs_matching (objfile,
						    file_matcher,
						    name_matcher,
						    kind, data);
}

static struct symtab *
debug_qf_find_pc_sect_symtab (struct objfile *objfile,
			      struct minimal_symbol *msymbol,
			      CORE_ADDR pc,
			      struct obj_section *section,
			      int warn_if_readin)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  struct symtab *retval;

  fprintf_filtered (gdb_stdlog,
		    "qf->find_pc_sect_symtab (%s, %s, %s, %s, %d)\n",
		    debug_objfile_name (objfile),
		    host_address_to_string (msymbol),
		    hex_string (pc),
		    host_address_to_string (section),
		    warn_if_readin);

  retval = debug_data->real_sf->qf->find_pc_sect_symtab (objfile, msymbol,
							 pc, section,
							 warn_if_readin);

  fprintf_filtered (gdb_stdlog, "qf->find_pc_sect_symtab (...) = %s\n",
		    retval ? debug_symtab_name (retval) : "NULL");

  return retval;
}

static void
debug_qf_map_symbol_filenames (struct objfile *objfile,
			       symbol_filename_ftype *fun, void *data,
			       int need_fullname)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  fprintf_filtered (gdb_stdlog,
		    "qf->map_symbol_filenames (%s, %s, %s, %d)\n",
		    debug_objfile_name (objfile),
		    host_address_to_string (fun),
		    host_address_to_string (data),
		    need_fullname);

  debug_data->real_sf->qf->map_symbol_filenames (objfile, fun, data,
						 need_fullname);
}

static const struct quick_symbol_functions debug_sym_quick_functions =
{
  debug_qf_has_symbols,
  debug_qf_find_last_source_symtab,
  debug_qf_forget_cached_source_info,
  debug_qf_map_symtabs_matching_filename,
  debug_qf_lookup_symbol,
  debug_qf_print_stats,
  debug_qf_dump,
  debug_qf_relocate,
  debug_qf_expand_symtabs_for_function,
  debug_qf_expand_all_symtabs,
  debug_qf_expand_symtabs_with_fullname,
  debug_qf_map_matching_symbols,
  debug_qf_expand_symtabs_matching,
  debug_qf_find_pc_sect_symtab,
  debug_qf_map_symbol_filenames
};

/* Debugging version of struct sym_probe_fns.  */

static VEC (probe_p) *
debug_sym_get_probes (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  VEC (probe_p) *retval;

  retval = debug_data->real_sf->sym_probe_fns->sym_get_probes (objfile);

  fprintf_filtered (gdb_stdlog,
		    "probes->sym_get_probes (%s) = %s\n",
		    debug_objfile_name (objfile),
		    host_address_to_string (retval));

  return retval;
}

static unsigned
debug_sym_get_probe_argument_count (struct probe *probe)
{
  struct objfile *objfile = probe->objfile;
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  unsigned retval;

  retval = debug_data->real_sf->sym_probe_fns->sym_get_probe_argument_count
    (probe);

  fprintf_filtered (gdb_stdlog,
		    "probes->sym_get_probe_argument_count (%s) = %u\n",
		    host_address_to_string (probe), retval);

  return retval;
}

static int
debug_can_evaluate_probe_arguments (struct probe *probe)
{
  struct objfile *objfile = probe->objfile;
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  int retval;

  retval = debug_data->real_sf->sym_probe_fns->can_evaluate_probe_arguments
    (probe);

  fprintf_filtered (gdb_stdlog,
		    "probes->can_evaluate_probe_arguments (%s) = %d\n",
		    host_address_to_string (probe), retval);

  return retval;
}

static struct value *
debug_sym_evaluate_probe_argument (struct probe *probe, unsigned n)
{
  struct objfile *objfile = probe->objfile;
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  struct value *retval;

  fprintf_filtered (gdb_stdlog,
		    "probes->sym_evaluate_probe_argument (%s, %u)\n",
		    host_address_to_string (probe), n);

  retval = debug_data->real_sf->sym_probe_fns->sym_evaluate_probe_argument
    (probe, n);

  fprintf_filtered (gdb_stdlog,
		    "probes->sym_evaluate_probe_argument (...) = %s\n",
		    host_address_to_string (retval));

  return retval;
}

static void
debug_sym_compile_to_ax (struct probe *probe, struct agent_expr *expr,
			 struct axs_value *value, unsigned n)
{
  struct objfile *objfile = probe->objfile;
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog,
		    "probes->sym_compile_to_ax (%s, %s, %s, %u)\n",
		    host_address_to_string (probe),
		    host_address_to_string (expr),
		    host_address_to_string (value), n);

  debug_data->real_sf->sym_probe_fns->sym_compile_to_ax
    (probe, expr, value, n);
}

static void
debug_sym_relocate_probe (struct objfile *objfile,
			  const struct section_offsets *new_offsets,
			  const struct section_offsets *delta)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog,
		    "probes->sym_relocate_probe (%s, %s, %s)\n",
		    debug_objfile_name (objfile),
		    host_address_to_string (new_offsets),
		    host_address_to_string (delta));

  debug_data->real_sf->sym_probe_fns->sym_relocate_probe
    (objfile, new_offsets, delta);
}

static const struct sym_probe_fns debug_sym_probe_fns =
{
  debug_sym_get_probes,
  debug_sym_get_probe_argument_count,
  debug_can_evaluate_probe_arguments,
  debug_sym_evaluate_probe_argument,
  debug_sym_compile_to_ax,
  debug_sym_relocate_probe
};

/* Debugging version of struct sym_fns.  */

static void
debug_sym_new_init (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "sf->sym_new_init (%s)\n",
		    debug_objfile_name (objfile));

  debug_data->real_sf->sym_new_init (objfile);
}

static void
debug_sym_init (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "sf->sym_init (%s)\n",
		    debug_objfile_name (objfile));

  debug_data->real_sf->sym_init (objfile);
}

static void
debug_sym_read (struct objfile *objfile, int symfile_flags)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "sf->sym_read (%s, 0x%x)\n",
		    debug_objfile_name (objfile), symfile_flags);

  debug_data->real_sf->sym_read (objfile, symfile_flags);
}

static void
debug_sym_read_psymbols (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "sf->sym_read_psymbols (%s)\n",
		    debug_objfile_name (objfile));

  debug_data->real_sf->sym_read_psymbols (objfile);
}

static void
debug_sym_finish (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "sf->sym_finish (%s)\n",
		    debug_objfile_name (objfile));

  debug_data->real_sf->sym_finish (objfile);
}

static void
debug_sym_offsets (struct objfile *objfile,
		   const struct section_addr_info *info)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "sf->sym_offsets (%s, %s)\n",
		    debug_objfile_name (objfile),
		    host_address_to_string (info));

  debug_data->real_sf->sym_offsets (objfile, info);
}

static struct symfile_segment_data *
debug_sym_segments (bfd *abfd)
{
  /* This API function is annoying, it doesn't take a "this" pointer.
     Fortunately it is only used in one place where we (re-)lookup the
     sym_fns table to use.  Thus we will never be called.  */
  gdb_assert_not_reached ("debug_sym_segments called");
}

static void
debug_sym_read_linetable (struct objfile *objfile)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);

  fprintf_filtered (gdb_stdlog, "sf->sym_read_linetable (%s)\n",
		    debug_objfile_name (objfile));

  debug_data->real_sf->sym_read_linetable (objfile);
}

static bfd_byte *
debug_sym_relocate (struct objfile *objfile, asection *sectp, bfd_byte *buf)
{
  const struct debug_sym_fns_data *debug_data =
    objfile_data (objfile, symfile_debug_objfile_data_key);
  bfd_byte *retval;

  retval = debug_data->real_sf->sym_relocate (objfile, sectp, buf);

  fprintf_filtered (gdb_stdlog,
		    "sf->sym_relocate (%s, %s, %s) = %s\n",
		    debug_objfile_name (objfile),
		    host_address_to_string (sectp),
		    host_address_to_string (buf),
		    host_address_to_string (retval));

  return retval;
}

/* Template of debugging version of struct sym_fns.
   A copy is made, with sym_flavour updated, and a pointer to the real table
   installed in real_sf, and then a pointer to the copy is installed in the
   objfile.  */

static const struct sym_fns debug_sym_fns =
{
  debug_sym_new_init,
  debug_sym_init,
  debug_sym_read,
  debug_sym_read_psymbols,
  debug_sym_finish,
  debug_sym_offsets,
  debug_sym_segments,
  debug_sym_read_linetable,
  debug_sym_relocate,
  &debug_sym_probe_fns,
  &debug_sym_quick_functions
};

/* Free the copy of sym_fns recorded in the registry.  */

static void
symfile_debug_free_objfile (struct objfile *objfile, void *datum)
{
  xfree (datum);
}

/* Install the debugging versions of the symfile functions for OBJFILE.
   Do not call this if the debug versions are already installed.  */

static void
install_symfile_debug_logging (struct objfile *objfile)
{
  const struct sym_fns *real_sf;
  struct debug_sym_fns_data *debug_data;

  /* The debug versions should not already be installed.  */
  gdb_assert (!symfile_debug_installed (objfile));

  real_sf = objfile->sf;

  /* Alas we have to preserve NULL entries in REAL_SF.  */
  debug_data = XZALLOC (struct debug_sym_fns_data);

#define COPY_SF_PTR(from, to, name, func)	\
  do {						\
    if ((from)->name)				\
      (to)->debug_sf.name = func;		\
  } while (0)

  COPY_SF_PTR (real_sf, debug_data, sym_new_init, debug_sym_new_init);
  COPY_SF_PTR (real_sf, debug_data, sym_init, debug_sym_init);
  COPY_SF_PTR (real_sf, debug_data, sym_read, debug_sym_read);
  COPY_SF_PTR (real_sf, debug_data, sym_read_psymbols,
	       debug_sym_read_psymbols);
  COPY_SF_PTR (real_sf, debug_data, sym_finish, debug_sym_finish);
  COPY_SF_PTR (real_sf, debug_data, sym_offsets, debug_sym_offsets);
  COPY_SF_PTR (real_sf, debug_data, sym_segments, debug_sym_segments);
  COPY_SF_PTR (real_sf, debug_data, sym_read_linetable,
	       debug_sym_read_linetable);
  COPY_SF_PTR (real_sf, debug_data, sym_relocate, debug_sym_relocate);
  if (real_sf->sym_probe_fns)
    debug_data->debug_sf.sym_probe_fns = &debug_sym_probe_fns;
  debug_data->debug_sf.qf = &debug_sym_quick_functions;

#undef COPY_SF_PTR

  debug_data->real_sf = real_sf;
  set_objfile_data (objfile, symfile_debug_objfile_data_key, debug_data);
  objfile->sf = &debug_data->debug_sf;
}

/* Uninstall the debugging versions of the symfile functions for OBJFILE.
   Do not call this if the debug versions are not installed.  */

static void
uninstall_symfile_debug_logging (struct objfile *objfile)
{
  struct debug_sym_fns_data *debug_data;

  /* The debug versions should be currently installed.  */
  gdb_assert (symfile_debug_installed (objfile));

  debug_data = objfile_data (objfile, symfile_debug_objfile_data_key);

  objfile->sf = debug_data->real_sf;
  xfree (debug_data);
  set_objfile_data (objfile, symfile_debug_objfile_data_key, NULL);
}

/* Call this function to set OBJFILE->SF.
   Do not set OBJFILE->SF directly.  */

void
objfile_set_sym_fns (struct objfile *objfile, const struct sym_fns *sf)
{
  if (symfile_debug_installed (objfile))
    {
      gdb_assert (debug_symfile);
      /* Remove the current one, and reinstall a new one later.  */
      uninstall_symfile_debug_logging (objfile);
    }

  /* Assume debug logging is disabled.  */
  objfile->sf = sf;

  /* Turn debug logging on if enabled.  */
  if (debug_symfile)
    install_symfile_debug_logging (objfile);
}

static void
set_debug_symfile (char *args, int from_tty, struct cmd_list_element *c)
{
  struct program_space *pspace;
  struct objfile *objfile;

  ALL_PSPACES (pspace)
    ALL_PSPACE_OBJFILES (pspace, objfile)
    {
      if (debug_symfile)
	{
	  if (!symfile_debug_installed (objfile))
	    install_symfile_debug_logging (objfile);
	}
      else
	{
	  if (symfile_debug_installed (objfile))
	    uninstall_symfile_debug_logging (objfile);
	}
    }
}

static void
show_debug_symfile (struct ui_file *file, int from_tty,
			struct cmd_list_element *c, const char *value)
{
  fprintf_filtered (file, _("Symfile debugging is %s.\n"), value);
}

initialize_file_ftype _initialize_symfile_debug;

void
_initialize_symfile_debug (void)
{
  symfile_debug_objfile_data_key
    = register_objfile_data_with_cleanup (NULL, symfile_debug_free_objfile);

  add_setshow_boolean_cmd ("symfile", no_class, &debug_symfile, _("\
Set debugging of the symfile functions."), _("\
Show debugging of the symfile functions."), _("\
When enabled, all calls to the symfile functions are logged."),
			   set_debug_symfile, show_debug_symfile,
			   &setdebuglist, &showdebuglist);

  /* Note: We don't need a new-objfile observer because debug logging
     will be installed when objfile init'n calls objfile_set_sym_fns.  */
}
