view libinterp/corefcn/toplev.h @ 17787:175b392e91fe

Use GNU style coding conventions for code in libinterp/ * libinterp/corefcn/Cell.h, libinterp/corefcn/__contourc__.cc, libinterp/corefcn/__dispatch__.cc, libinterp/corefcn/__lin_interpn__.cc, libinterp/corefcn/__pchip_deriv__.cc, libinterp/corefcn/__qp__.cc, libinterp/corefcn/balance.cc, libinterp/corefcn/besselj.cc, libinterp/corefcn/betainc.cc, libinterp/corefcn/bitfcns.cc, libinterp/corefcn/bsxfun.cc, libinterp/corefcn/c-file-ptr-stream.cc, libinterp/corefcn/c-file-ptr-stream.h, libinterp/corefcn/cellfun.cc, libinterp/corefcn/colloc.cc, libinterp/corefcn/comment-list.h, libinterp/corefcn/conv2.cc, libinterp/corefcn/daspk.cc, libinterp/corefcn/dasrt.cc, libinterp/corefcn/dassl.cc, libinterp/corefcn/data.cc, libinterp/corefcn/debug.cc, libinterp/corefcn/defaults.cc, libinterp/corefcn/defaults.in.h, libinterp/corefcn/defun-int.h, libinterp/corefcn/defun.cc, libinterp/corefcn/det.cc, libinterp/corefcn/dirfns.cc, libinterp/corefcn/display.cc, libinterp/corefcn/dlmread.cc, libinterp/corefcn/dot.cc, libinterp/corefcn/dynamic-ld.cc, libinterp/corefcn/dynamic-ld.h, libinterp/corefcn/eig.cc, libinterp/corefcn/ellipj.cc, libinterp/corefcn/error.cc, libinterp/corefcn/error.h, libinterp/corefcn/event-queue.h, libinterp/corefcn/fft.cc, libinterp/corefcn/fft2.cc, libinterp/corefcn/fftn.cc, libinterp/corefcn/file-io.cc, libinterp/corefcn/filter.cc, libinterp/corefcn/find.cc, libinterp/corefcn/gammainc.cc, libinterp/corefcn/gcd.cc, libinterp/corefcn/getgrent.cc, libinterp/corefcn/getpwent.cc, libinterp/corefcn/getrusage.cc, libinterp/corefcn/givens.cc, libinterp/corefcn/gl-render.cc, libinterp/corefcn/gl2ps-renderer.cc, libinterp/corefcn/gl2ps-renderer.h, libinterp/corefcn/graphics.cc, libinterp/corefcn/graphics.in.h, libinterp/corefcn/gripes.cc, libinterp/corefcn/gripes.h, libinterp/corefcn/help.cc, libinterp/corefcn/hess.cc, libinterp/corefcn/hex2num.cc, libinterp/corefcn/input.cc, libinterp/corefcn/input.h, libinterp/corefcn/inv.cc, libinterp/corefcn/jit-ir.h, libinterp/corefcn/jit-typeinfo.cc, libinterp/corefcn/jit-typeinfo.h, libinterp/corefcn/jit-util.h, libinterp/corefcn/kron.cc, libinterp/corefcn/load-path.cc, libinterp/corefcn/load-path.h, libinterp/corefcn/load-save.cc, libinterp/corefcn/load-save.h, libinterp/corefcn/lookup.cc, libinterp/corefcn/ls-ascii-helper.cc, libinterp/corefcn/ls-hdf5.cc, libinterp/corefcn/ls-hdf5.h, libinterp/corefcn/ls-mat-ascii.cc, libinterp/corefcn/ls-mat-ascii.h, libinterp/corefcn/ls-mat4.cc, libinterp/corefcn/ls-mat5.cc, libinterp/corefcn/ls-mat5.h, libinterp/corefcn/ls-oct-ascii.cc, libinterp/corefcn/lsode.cc, libinterp/corefcn/lu.cc, libinterp/corefcn/luinc.cc, libinterp/corefcn/mappers.cc, libinterp/corefcn/matrix_type.cc, libinterp/corefcn/max.cc, libinterp/corefcn/md5sum.cc, libinterp/corefcn/mex.cc, libinterp/corefcn/mexproto.h, libinterp/corefcn/mgorth.cc, libinterp/corefcn/mxarray.in.h, libinterp/corefcn/nproc.cc, libinterp/corefcn/oct-hist.cc, libinterp/corefcn/oct-lvalue.h, libinterp/corefcn/oct-map.cc, libinterp/corefcn/oct-map.h, libinterp/corefcn/oct-obj.h, libinterp/corefcn/oct-prcstrm.h, libinterp/corefcn/oct-stdstrm.h, libinterp/corefcn/oct-stream.cc, libinterp/corefcn/oct-stream.h, libinterp/corefcn/octave-link.cc, libinterp/corefcn/octave-link.h, libinterp/corefcn/pager.cc, libinterp/corefcn/pinv.cc, libinterp/corefcn/pr-output.cc, libinterp/corefcn/procstream.h, libinterp/corefcn/profiler.cc, libinterp/corefcn/pt-jit.cc, libinterp/corefcn/pt-jit.h, libinterp/corefcn/quad.cc, libinterp/corefcn/quadcc.cc, libinterp/corefcn/qz.cc, libinterp/corefcn/rand.cc, libinterp/corefcn/rcond.cc, libinterp/corefcn/regexp.cc, libinterp/corefcn/schur.cc, libinterp/corefcn/sighandlers.cc, libinterp/corefcn/sighandlers.h, libinterp/corefcn/sparse-xdiv.cc, libinterp/corefcn/sparse-xdiv.h, libinterp/corefcn/sparse-xpow.cc, libinterp/corefcn/sparse.cc, libinterp/corefcn/spparms.cc, libinterp/corefcn/sqrtm.cc, libinterp/corefcn/str2double.cc, libinterp/corefcn/strfind.cc, libinterp/corefcn/strfns.cc, libinterp/corefcn/sub2ind.cc, libinterp/corefcn/svd.cc, libinterp/corefcn/syl.cc, libinterp/corefcn/symtab.cc, libinterp/corefcn/symtab.h, libinterp/corefcn/syscalls.cc, libinterp/corefcn/sysdep.cc, libinterp/corefcn/sysdep.h, libinterp/corefcn/time.cc, libinterp/corefcn/toplev.cc, libinterp/corefcn/toplev.h, libinterp/corefcn/tril.cc, libinterp/corefcn/txt-eng-ft.cc, libinterp/corefcn/txt-eng-ft.h, libinterp/corefcn/txt-eng.h, libinterp/corefcn/typecast.cc, libinterp/corefcn/urlwrite.cc, libinterp/corefcn/utils.cc, libinterp/corefcn/variables.cc, libinterp/corefcn/variables.h, libinterp/corefcn/xdiv.cc, libinterp/corefcn/xdiv.h, libinterp/corefcn/xnorm.h, libinterp/corefcn/xpow.cc, libinterp/corefcn/xpow.h, libinterp/corefcn/zfstream.cc, libinterp/corefcn/zfstream.h, libinterp/dldfcn/__delaunayn__.cc, libinterp/dldfcn/__dsearchn__.cc, libinterp/dldfcn/__eigs__.cc, libinterp/dldfcn/__fltk_uigetfile__.cc, libinterp/dldfcn/__glpk__.cc, libinterp/dldfcn/__init_fltk__.cc, libinterp/dldfcn/__init_gnuplot__.cc, libinterp/dldfcn/__magick_read__.cc, libinterp/dldfcn/__voronoi__.cc, libinterp/dldfcn/amd.cc, libinterp/dldfcn/ccolamd.cc, libinterp/dldfcn/chol.cc, libinterp/dldfcn/colamd.cc, libinterp/dldfcn/convhulln.cc, libinterp/dldfcn/dmperm.cc, libinterp/dldfcn/fftw.cc, libinterp/dldfcn/qr.cc, libinterp/dldfcn/symbfact.cc, libinterp/dldfcn/symrcm.cc, libinterp/dldfcn/tsearch.cc, libinterp/octave-value/ov-base-diag.cc, libinterp/octave-value/ov-base-diag.h, libinterp/octave-value/ov-base-int.cc, libinterp/octave-value/ov-base-int.h, libinterp/octave-value/ov-base-mat.h, libinterp/octave-value/ov-base-scalar.cc, libinterp/octave-value/ov-base-scalar.h, libinterp/octave-value/ov-base-sparse.cc, libinterp/octave-value/ov-base-sparse.h, libinterp/octave-value/ov-base.cc, libinterp/octave-value/ov-base.h, libinterp/octave-value/ov-bool-mat.cc, libinterp/octave-value/ov-bool-mat.h, libinterp/octave-value/ov-bool-sparse.cc, libinterp/octave-value/ov-bool-sparse.h, libinterp/octave-value/ov-bool.cc, libinterp/octave-value/ov-bool.h, libinterp/octave-value/ov-builtin.cc, libinterp/octave-value/ov-builtin.h, libinterp/octave-value/ov-cell.cc, libinterp/octave-value/ov-cell.h, libinterp/octave-value/ov-ch-mat.cc, libinterp/octave-value/ov-ch-mat.h, libinterp/octave-value/ov-class.cc, libinterp/octave-value/ov-class.h, libinterp/octave-value/ov-colon.h, libinterp/octave-value/ov-complex.cc, libinterp/octave-value/ov-complex.h, libinterp/octave-value/ov-cx-diag.cc, libinterp/octave-value/ov-cx-diag.h, libinterp/octave-value/ov-cx-mat.cc, libinterp/octave-value/ov-cx-mat.h, libinterp/octave-value/ov-cx-sparse.cc, libinterp/octave-value/ov-cx-sparse.h, libinterp/octave-value/ov-dld-fcn.h, libinterp/octave-value/ov-fcn-handle.cc, libinterp/octave-value/ov-fcn-handle.h, libinterp/octave-value/ov-fcn-inline.cc, libinterp/octave-value/ov-fcn-inline.h, libinterp/octave-value/ov-fcn.h, libinterp/octave-value/ov-float.cc, libinterp/octave-value/ov-float.h, libinterp/octave-value/ov-flt-complex.cc, libinterp/octave-value/ov-flt-complex.h, libinterp/octave-value/ov-flt-cx-diag.cc, libinterp/octave-value/ov-flt-cx-diag.h, libinterp/octave-value/ov-flt-cx-mat.cc, libinterp/octave-value/ov-flt-cx-mat.h, libinterp/octave-value/ov-flt-re-diag.cc, libinterp/octave-value/ov-flt-re-diag.h, libinterp/octave-value/ov-flt-re-mat.cc, libinterp/octave-value/ov-flt-re-mat.h, libinterp/octave-value/ov-int16.cc, libinterp/octave-value/ov-int32.cc, libinterp/octave-value/ov-int64.cc, libinterp/octave-value/ov-int8.cc, libinterp/octave-value/ov-intx.h, libinterp/octave-value/ov-java.cc, libinterp/octave-value/ov-lazy-idx.h, libinterp/octave-value/ov-mex-fcn.cc, libinterp/octave-value/ov-mex-fcn.h, libinterp/octave-value/ov-null-mat.cc, libinterp/octave-value/ov-null-mat.h, libinterp/octave-value/ov-oncleanup.cc, libinterp/octave-value/ov-perm.cc, libinterp/octave-value/ov-perm.h, libinterp/octave-value/ov-range.cc, libinterp/octave-value/ov-range.h, libinterp/octave-value/ov-re-diag.cc, libinterp/octave-value/ov-re-diag.h, libinterp/octave-value/ov-re-mat.cc, libinterp/octave-value/ov-re-mat.h, libinterp/octave-value/ov-re-sparse.cc, libinterp/octave-value/ov-re-sparse.h, libinterp/octave-value/ov-scalar.cc, libinterp/octave-value/ov-scalar.h, libinterp/octave-value/ov-str-mat.cc, libinterp/octave-value/ov-str-mat.h, libinterp/octave-value/ov-struct.cc, libinterp/octave-value/ov-struct.h, libinterp/octave-value/ov-type-conv.h, libinterp/octave-value/ov-typeinfo.cc, libinterp/octave-value/ov-typeinfo.h, libinterp/octave-value/ov-uint16.cc, libinterp/octave-value/ov-uint32.cc, libinterp/octave-value/ov-uint64.cc, libinterp/octave-value/ov-uint8.cc, libinterp/octave-value/ov-usr-fcn.cc, libinterp/octave-value/ov-usr-fcn.h, libinterp/octave-value/ov.cc, libinterp/octave-value/ov.h, libinterp/octave.cc, libinterp/operators/op-b-bm.cc, libinterp/operators/op-b-sbm.cc, libinterp/operators/op-bm-b.cc, libinterp/operators/op-bm-bm.cc, libinterp/operators/op-cdm-cdm.cc, libinterp/operators/op-chm.cc, libinterp/operators/op-class.cc, libinterp/operators/op-cm-cm.cc, libinterp/operators/op-cm-cs.cc, libinterp/operators/op-cm-s.cc, libinterp/operators/op-cm-scm.cc, libinterp/operators/op-cm-sm.cc, libinterp/operators/op-cs-cm.cc, libinterp/operators/op-cs-cs.cc, libinterp/operators/op-cs-scm.cc, libinterp/operators/op-cs-sm.cc, libinterp/operators/op-dm-dm.cc, libinterp/operators/op-dm-scm.cc, libinterp/operators/op-double-conv.cc, libinterp/operators/op-fcdm-fcdm.cc, libinterp/operators/op-fcm-fcm.cc, libinterp/operators/op-fcm-fcs.cc, libinterp/operators/op-fcm-fm.cc, libinterp/operators/op-fcm-fs.cc, libinterp/operators/op-fcs-fcm.cc, libinterp/operators/op-fcs-fcs.cc, libinterp/operators/op-fcs-fm.cc, libinterp/operators/op-fcs-fs.cc, libinterp/operators/op-fdm-fdm.cc, libinterp/operators/op-float-conv.cc, libinterp/operators/op-fm-fcm.cc, libinterp/operators/op-fm-fcs.cc, libinterp/operators/op-fm-fm.cc, libinterp/operators/op-fm-fs.cc, libinterp/operators/op-fs-fcm.cc, libinterp/operators/op-fs-fcs.cc, libinterp/operators/op-fs-fm.cc, libinterp/operators/op-fs-fs.cc, libinterp/operators/op-m-cm.cc, libinterp/operators/op-m-cs.cc, libinterp/operators/op-m-m.cc, libinterp/operators/op-m-s.cc, libinterp/operators/op-m-scm.cc, libinterp/operators/op-m-sm.cc, libinterp/operators/op-pm-scm.cc, libinterp/operators/op-range.cc, libinterp/operators/op-s-cm.cc, libinterp/operators/op-s-cs.cc, libinterp/operators/op-s-scm.cc, libinterp/operators/op-sbm-b.cc, libinterp/operators/op-sbm-bm.cc, libinterp/operators/op-sbm-sbm.cc, libinterp/operators/op-scm-cm.cc, libinterp/operators/op-scm-cs.cc, libinterp/operators/op-scm-m.cc, libinterp/operators/op-scm-s.cc, libinterp/operators/op-scm-scm.cc, libinterp/operators/op-scm-sm.cc, libinterp/operators/op-sm-cm.cc, libinterp/operators/op-sm-m.cc, libinterp/operators/op-sm-s.cc, libinterp/operators/op-sm-scm.cc, libinterp/operators/op-sm-sm.cc, libinterp/operators/op-str-m.cc, libinterp/operators/op-str-s.cc, libinterp/operators/op-str-str.cc, libinterp/operators/ops.h, libinterp/parse-tree/lex.h, libinterp/parse-tree/parse.h, libinterp/parse-tree/pt-arg-list.cc, libinterp/parse-tree/pt-arg-list.h, libinterp/parse-tree/pt-assign.cc, libinterp/parse-tree/pt-assign.h, libinterp/parse-tree/pt-binop.cc, libinterp/parse-tree/pt-binop.h, libinterp/parse-tree/pt-bp.h, libinterp/parse-tree/pt-cbinop.cc, libinterp/parse-tree/pt-check.cc, libinterp/parse-tree/pt-colon.cc, libinterp/parse-tree/pt-colon.h, libinterp/parse-tree/pt-const.cc, libinterp/parse-tree/pt-decl.cc, libinterp/parse-tree/pt-decl.h, libinterp/parse-tree/pt-eval.cc, libinterp/parse-tree/pt-except.h, libinterp/parse-tree/pt-exp.h, libinterp/parse-tree/pt-fcn-handle.cc, libinterp/parse-tree/pt-id.cc, libinterp/parse-tree/pt-id.h, libinterp/parse-tree/pt-idx.cc, libinterp/parse-tree/pt-idx.h, libinterp/parse-tree/pt-loop.h, libinterp/parse-tree/pt-mat.cc, libinterp/parse-tree/pt-misc.cc, libinterp/parse-tree/pt-misc.h, libinterp/parse-tree/pt-pr-code.cc, libinterp/parse-tree/pt-select.h, libinterp/parse-tree/pt-stmt.h, libinterp/parse-tree/token.h, libinterp/version.cc: Use GNU style coding conventions for code in libinterp/
author Rik <rik@octave.org>
date Mon, 28 Oct 2013 19:51:46 -0700
parents d63878346099
children bc139ccccef9
line wrap: on
line source

/*

Copyright (C) 1993-2013 John W. Eaton

This file is part of Octave.

Octave 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.

Octave 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 Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

#if !defined (octave_toplev_h)
#define octave_toplev_h 1

#include <cstdio>

#include <deque>
#include <string>

class octave_value;
class octave_value_list;
class octave_function;
class octave_user_script;
class tree_statement;
class tree_statement_list;
class charMatrix;

#include "quit.h"

#include "input.h"
#include "oct-map.h"
#include "symtab.h"


typedef void (*octave_exit_func) (int);
extern OCTINTERP_API octave_exit_func octave_exit;

extern OCTINTERP_API bool quit_allowed;

extern OCTINTERP_API bool quitting_gracefully;

extern OCTINTERP_API int exit_status;

extern OCTINTERP_API void
clean_up_and_exit (int status, bool safe_to_return = false);

extern OCTINTERP_API void recover_from_exception (void);

extern OCTINTERP_API int main_loop (void);

extern OCTINTERP_API void
octave_add_atexit_function (const std::string& fname);

extern OCTINTERP_API bool
octave_remove_atexit_function (const std::string& fname);

// TRUE means we are ready to interpret commands, but not everything
// is ready for interactive use.
extern OCTINTERP_API bool octave_interpreter_ready;

// TRUE means we've processed all the init code and we are good to go.
extern OCTINTERP_API bool octave_initialized;

class
OCTINTERP_API
octave_call_stack
{
private:

  struct call_stack_elt
  {
    call_stack_elt (octave_function *f, symbol_table::scope_id s,
                    symbol_table::context_id c, size_t p = 0)
      : fcn (f), line (-1), column (-1), scope (s), context (c), prev (p)
    { }

    call_stack_elt (const call_stack_elt& elt)
      : fcn (elt.fcn), line (elt.line), column (elt.column),
        scope (elt.scope), context (elt.context), prev (elt.prev)
    { }

    octave_function *fcn;
    int line;
    int column;
    symbol_table::scope_id scope;
    symbol_table::context_id context;
    size_t prev;
  };

protected:

  octave_call_stack (void) : cs (), curr_frame (0) { }

public:

  typedef std::deque<call_stack_elt>::iterator iterator;
  typedef std::deque<call_stack_elt>::const_iterator const_iterator;

  typedef std::deque<call_stack_elt>::reverse_iterator
    reverse_iterator;
  typedef std::deque<call_stack_elt>::const_reverse_iterator
    const_reverse_iterator;

  static void create_instance (void);

  static bool instance_ok (void)
  {
    bool retval = true;

    if (! instance)
      create_instance ();

    if (! instance)
      {
        ::error ("unable to create call stack object!");

        retval = false;
      }

    return retval;
  }

  // Current function (top of stack).
  static octave_function *current (void)
  {
    return instance_ok () ? instance->do_current () : 0;
  }

  // Current line in current function.
  static int current_line (void)
  {
    return instance_ok () ? instance->do_current_line () : -1;
  }

  // Current column in current function.
  static int current_column (void)
  {
    return instance_ok () ? instance->do_current_column () : -1;
  }

  // Line in user code caller.
  static int caller_user_code_line (void)
  {
    return instance_ok () ? instance->do_caller_user_code_line () : -1;
  }

  // Column in user code caller.
  static int caller_user_code_column (void)
  {
    return instance_ok () ? instance->do_caller_user_code_column () : -1;
  }

  // Caller function, may be built-in.
  static octave_function *caller (void)
  {
    return instance_ok () ? instance->do_caller () : 0;
  }

  static size_t current_frame (void)
  {
    return instance_ok () ? instance->do_current_frame () : 0;
  }

  static size_t size (void)
  {
    return instance_ok () ? instance->do_size () : 0;
  }

  static size_t num_user_code_frames (octave_idx_type& curr_user_frame)
  {
    return instance_ok ()
           ? instance->do_num_user_code_frames (curr_user_frame) : 0;
  }

  static symbol_table::scope_id current_scope (void)
  {
    return instance_ok () ? instance->do_current_scope () : 0;
  }

  static symbol_table::context_id current_context (void)
  {
    return instance_ok () ? instance->do_current_context () : 0;
  }

  // Function at location N on the call stack (N == 0 is current), may
  // be built-in.
  static octave_function *element (size_t n)
  {
    return instance_ok () ? instance->do_element (n) : 0;
  }

  // First user-defined function on the stack.
  static octave_user_code *caller_user_code (size_t nskip = 0)
  {
    return instance_ok () ? instance->do_caller_user_code (nskip) : 0;
  }

  static void
  push (octave_function *f,
        symbol_table::scope_id scope = symbol_table::current_scope (),
        symbol_table::context_id context = symbol_table::current_context ())
  {
    if (instance_ok ())
      instance->do_push (f, scope, context);
  }

  static void
  push (symbol_table::scope_id scope = symbol_table::current_scope (),
        symbol_table::context_id context = symbol_table::current_context ())
  {
    if (instance_ok ())
      instance->do_push (0, scope, context);
  }

  static void set_location (int l, int c)
  {
    if (instance_ok ())
      instance->do_set_location (l, c);
  }

  static void set_line (int l)
  {
    if (instance_ok ())
      instance->do_set_line (l);
  }

  static void set_column (int c)
  {
    if (instance_ok ())
      instance->do_set_column (c);
  }

  static bool goto_frame (size_t n = 0, bool verbose = false)
  {
    return instance_ok () ? instance->do_goto_frame (n, verbose) : false;
  }

  static void restore_frame (size_t n)
  {
    goto_frame (n);
  }

  static bool goto_frame_relative (int n, bool verbose = false)
  {
    return instance_ok ()
           ? instance->do_goto_frame_relative (n, verbose) : false;
  }

  static void goto_caller_frame (void)
  {
    if (instance_ok ())
      instance->do_goto_caller_frame ();
  }

  static void goto_base_frame (void)
  {
    if (instance_ok ())
      instance->do_goto_base_frame ();
  }

  static octave_map backtrace (size_t nskip, octave_idx_type& curr_user_frame)
  {
    return instance_ok ()
           ? instance->do_backtrace (nskip, curr_user_frame) : octave_map ();
  }

  static octave_map empty_backtrace (void);

  static void pop (void)
  {
    if (instance_ok ())
      instance->do_pop ();
  }

  static void clear (void)
  {
    if (instance_ok ())
      instance->do_clear ();
  }

  static void backtrace_error_message (void)
  {
    if (instance_ok ())
      instance->do_backtrace_error_message ();
  }

private:

  // The current call stack.
  std::deque<call_stack_elt> cs;

  size_t curr_frame;

  static octave_call_stack *instance;

  static void cleanup_instance (void) { delete instance; instance = 0; }

  int do_current_line (void) const;

  int do_current_column (void) const;

  int do_caller_user_code_line (void) const;

  int do_caller_user_code_column (void) const;

  octave_function *do_caller (void) const
  {
    return curr_frame > 1 ? cs[curr_frame-1].fcn : cs[0].fcn;
  }

  size_t do_current_frame (void) { return curr_frame; }

  size_t do_size (void) { return cs.size (); }

  size_t do_num_user_code_frames (octave_idx_type& curr_user_frame) const;

  symbol_table::scope_id do_current_scope (void) const
  {
    return curr_frame > 0 && curr_frame < cs.size ()
           ? cs[curr_frame].scope : 0;
  }

  symbol_table::context_id do_current_context (void) const
  {
    return curr_frame > 0 && curr_frame < cs.size ()
           ? cs[curr_frame].context : 0;
  }

  octave_function *do_element (size_t n)
  {
    octave_function *retval = 0;

    if (cs.size () > n)
      {
        call_stack_elt& elt = cs[n];
        retval = elt.fcn;
      }

    return retval;
  }

  octave_user_code *do_caller_user_code (size_t nskip) const;

  void do_push (octave_function *f, symbol_table::scope_id scope,
                symbol_table::context_id context)
  {
    size_t prev_frame = curr_frame;
    curr_frame = cs.size ();
    cs.push_back (call_stack_elt (f, scope, context, prev_frame));
    symbol_table::set_scope_and_context (scope, context);
  }

  octave_function *do_current (void) const
  {
    octave_function *retval = 0;

    if (! cs.empty ())
      {
        const call_stack_elt& elt = cs[curr_frame];
        retval = elt.fcn;
      }

    return retval;
  }

  void do_set_location (int l, int c)
  {
    if (! cs.empty ())
      {
        call_stack_elt& elt = cs.back ();

        elt.line = l;
        elt.column = c;
      }
  }

  void do_set_line (int l)
  {
    if (! cs.empty ())
      {
        call_stack_elt& elt = cs.back ();

        elt.line = l;
      }
  }

  void do_set_column (int c)
  {
    if (! cs.empty ())
      {
        call_stack_elt& elt = cs.back ();

        elt.column = c;
      }
  }

  octave_map do_backtrace (size_t nskip,
                           octave_idx_type& curr_user_frame) const;

  bool do_goto_frame (size_t n, bool verbose);

  bool do_goto_frame_relative (int n, bool verbose);

  void do_goto_caller_frame (void);

  void do_goto_base_frame (void);

  void do_pop (void)
  {
    if (cs.size () > 1)
      {
        const call_stack_elt& elt = cs.back ();
        curr_frame = elt.prev;
        cs.pop_back ();
        const call_stack_elt& new_elt = cs[curr_frame];
        symbol_table::set_scope_and_context (new_elt.scope, new_elt.context);
      }
  }

  void do_clear (void) { cs.clear (); }

  void do_backtrace_error_message (void) const;
};

// Call a function with exceptions handled to avoid problems with
// errors while shutting down.

#define OCTAVE_IGNORE_EXCEPTION(E) \
  catch (E) \
    { \
      std::cerr << "error: ignoring " #E " while preparing to exit" << std::endl; \
      recover_from_exception (); \
    }

#define OCTAVE_SAFE_CALL(F, ARGS) \
  do \
    { \
      try \
        { \
          unwind_protect frame; \
 \
          frame.protect_var (Vdebug_on_error); \
          frame.protect_var (Vdebug_on_warning); \
 \
          Vdebug_on_error = false; \
          Vdebug_on_warning = false; \
 \
          F ARGS; \
        } \
      OCTAVE_IGNORE_EXCEPTION (octave_interrupt_exception) \
      OCTAVE_IGNORE_EXCEPTION (octave_execution_exception) \
      OCTAVE_IGNORE_EXCEPTION (std::bad_alloc) \
 \
      if (error_state) \
        error_state = 0; \
    } \
  while (0)

#endif