gdb/python/py-prettyprint.c

   1 /* Python pretty-printing
   2
   3    Copyright (C) 2008-2023 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "objfiles.h"
  22 #include "symtab.h"
  23 #include "language.h"
  24 #include "valprint.h"
  25 #include "extension-priv.h"
  26 #include "python.h"
  27 #include "python-internal.h"
  28 #include "cli/cli-style.h"
  29
  30 /* Return type of print_string_repr.  */
  31
  32 enum gdbpy_string_repr_result
  33   {
  34     /* The string method returned None.  */
  35     string_repr_none,
  36     /* The string method had an error.  */
  37     string_repr_error,
  38     /* Everything ok.  */
  39     string_repr_ok
  40   };
  41
  42 /* If non-null, points to options that are in effect while
  43    printing.  */
  44 const struct value_print_options *gdbpy_current_print_options;
  45
  46 /* Helper function for find_pretty_printer which iterates over a list,
  47    calls each function and inspects output.  This will return a
  48    printer object if one recognizes VALUE.  If no printer is found, it
  49    will return None.  On error, it will set the Python error and
  50    return NULL.  */
  51
  52 static gdbpy_ref<>
  53 search_pp_list (PyObject *list, PyObject *value)
  54 {
  55   Py_ssize_t pp_list_size, list_index;
  56
  57   pp_list_size = PyList_Size (list);
  58   for (list_index = 0; list_index < pp_list_size; list_index++)
  59     {
  60       PyObject *function = PyList_GetItem (list, list_index);
  61       if (! function)
  62         return NULL;
  63
  64       /* Skip if disabled.  */
  65       if (PyObject_HasAttr (function, gdbpy_enabled_cst))
  66         {
  67           gdbpy_ref<> attr (PyObject_GetAttr (function, gdbpy_enabled_cst));
  68           int cmp;
  69
  70           if (attr == NULL)
  71             return NULL;
  72           cmp = PyObject_IsTrue (attr.get ());
  73           if (cmp == -1)
  74             return NULL;
  75
  76           if (!cmp)
  77             continue;
  78         }
  79
  80       gdbpy_ref<> printer (PyObject_CallFunctionObjArgs (function, value,
  81                                                          NULL));
  82       if (printer == NULL)
  83         return NULL;
  84       else if (printer != Py_None)
  85         return printer;
  86     }
  87
  88   return gdbpy_ref<>::new_reference (Py_None);
  89 }
  90
  91 /* Subroutine of find_pretty_printer to simplify it.
  92    Look for a pretty-printer to print VALUE in all objfiles.
  93    The result is NULL if there's an error and the search should be terminated.
  94    The result is Py_None, suitably inc-ref'd, if no pretty-printer was found.
  95    Otherwise the result is the pretty-printer function, suitably inc-ref'd.  */
  96
  97 static PyObject *
  98 find_pretty_printer_from_objfiles (PyObject *value)
  99 {
 100   for (objfile *obj : current_program_space->objfiles ())
 101     {
 102       gdbpy_ref<> objf = objfile_to_objfile_object (obj);
 103       if (objf == NULL)
 104         {
 105           /* Ignore the error and continue.  */
 106           PyErr_Clear ();
 107           continue;
 108         }
 109
 110       gdbpy_ref<> pp_list (objfpy_get_printers (objf.get (), NULL));
 111       gdbpy_ref<> function (search_pp_list (pp_list.get (), value));
 112
 113       /* If there is an error in any objfile list, abort the search and exit.  */
 114       if (function == NULL)
 115         return NULL;
 116
 117       if (function != Py_None)
 118         return function.release ();
 119     }
 120
 121   Py_RETURN_NONE;
 122 }
 123
 124 /* Subroutine of find_pretty_printer to simplify it.
 125    Look for a pretty-printer to print VALUE in the current program space.
 126    The result is NULL if there's an error and the search should be terminated.
 127    The result is Py_None, suitably inc-ref'd, if no pretty-printer was found.
 128    Otherwise the result is the pretty-printer function, suitably inc-ref'd.  */
 129
 130 static gdbpy_ref<>
 131 find_pretty_printer_from_progspace (PyObject *value)
 132 {
 133   gdbpy_ref<> obj = pspace_to_pspace_object (current_program_space);
 134
 135   if (obj == NULL)
 136     return NULL;
 137   gdbpy_ref<> pp_list (pspy_get_printers (obj.get (), NULL));
 138   return search_pp_list (pp_list.get (), value);
 139 }
 140
 141 /* Subroutine of find_pretty_printer to simplify it.
 142    Look for a pretty-printer to print VALUE in the gdb module.
 143    The result is NULL if there's an error and the search should be terminated.
 144    The result is Py_None, suitably inc-ref'd, if no pretty-printer was found.
 145    Otherwise the result is the pretty-printer function, suitably inc-ref'd.  */
 146
 147 static gdbpy_ref<>
 148 find_pretty_printer_from_gdb (PyObject *value)
 149 {
 150   /* Fetch the global pretty printer list.  */
 151   if (gdb_python_module == NULL
 152       || ! PyObject_HasAttrString (gdb_python_module, "pretty_printers"))
 153     return gdbpy_ref<>::new_reference (Py_None);
 154   gdbpy_ref<> pp_list (PyObject_GetAttrString (gdb_python_module,
 155                                                "pretty_printers"));
 156   if (pp_list == NULL || ! PyList_Check (pp_list.get ()))
 157     return gdbpy_ref<>::new_reference (Py_None);
 158
 159   return search_pp_list (pp_list.get (), value);
 160 }
 161
 162 /* Find the pretty-printing constructor function for VALUE.  If no
 163    pretty-printer exists, return None.  If one exists, return a new
 164    reference.  On error, set the Python error and return NULL.  */
 165
 166 static gdbpy_ref<>
 167 find_pretty_printer (PyObject *value)
 168 {
 169   /* Look at the pretty-printer list for each objfile
 170      in the current program-space.  */
 171   gdbpy_ref<> function (find_pretty_printer_from_objfiles (value));
 172   if (function == NULL || function != Py_None)
 173     return function;
 174
 175   /* Look at the pretty-printer list for the current program-space.  */
 176   function = find_pretty_printer_from_progspace (value);
 177   if (function == NULL || function != Py_None)
 178     return function;
 179
 180   /* Look at the pretty-printer list in the gdb module.  */
 181   return find_pretty_printer_from_gdb (value);
 182 }
 183
 184 /* Pretty-print a single value, via the printer object PRINTER.
 185    If the function returns a string, a PyObject containing the string
 186    is returned.  If the function returns Py_NONE that means the pretty
 187    printer returned the Python None as a value.  Otherwise, if the
 188    function returns a value,  *OUT_VALUE is set to the value, and NULL
 189    is returned.  On error, *OUT_VALUE is set to NULL, NULL is
 190    returned, with a python exception set.  */
 191
 192 static gdbpy_ref<>
 193 pretty_print_one_value (PyObject *printer, struct value **out_value)
 194 {
 195   gdbpy_ref<> result;
 196
 197   *out_value = NULL;
 198   try
 199     {
 200       if (!PyObject_HasAttr (printer, gdbpy_to_string_cst))
 201         result = gdbpy_ref<>::new_reference (Py_None);
 202       else
 203         {
 204           result.reset (PyObject_CallMethodObjArgs (printer, gdbpy_to_string_cst,
 205                                                     NULL));
 206           if (result != NULL)
 207             {
 208               if (! gdbpy_is_string (result.get ())
 209                   && ! gdbpy_is_lazy_string (result.get ())
 210                   && result != Py_None)
 211                 {
 212                   *out_value = convert_value_from_python (result.get ());
 213                   if (PyErr_Occurred ())
 214                     *out_value = NULL;
 215                   result = NULL;
 216                 }
 217             }
 218         }
 219     }
 220   catch (const gdb_exception &except)
 221     {
 222     }
 223
 224   return result;
 225 }
 226
 227 /* Return the display hint for the object printer, PRINTER.  Return
 228    NULL if there is no display_hint method, or if the method did not
 229    return a string.  On error, print stack trace and return NULL.  On
 230    success, return an xmalloc()d string.  */
 231 gdb::unique_xmalloc_ptr<char>
 232 gdbpy_get_display_hint (PyObject *printer)
 233 {
 234   gdb::unique_xmalloc_ptr<char> result;
 235
 236   if (! PyObject_HasAttr (printer, gdbpy_display_hint_cst))
 237     return NULL;
 238
 239   gdbpy_ref<> hint (PyObject_CallMethodObjArgs (printer, gdbpy_display_hint_cst,
 240                                                 NULL));
 241   if (hint != NULL)
 242     {
 243       if (gdbpy_is_string (hint.get ()))
 244         {
 245           result = python_string_to_host_string (hint.get ());
 246           if (result == NULL)
 247             gdbpy_print_stack ();
 248         }
 249     }
 250   else
 251     gdbpy_print_stack ();
 252
 253   return result;
 254 }
 255
 256 /* A wrapper for gdbpy_print_stack that ignores MemoryError.  */
 257
 258 static void
 259 print_stack_unless_memory_error (struct ui_file *stream)
 260 {
 261   if (PyErr_ExceptionMatches (gdbpy_gdb_memory_error))
 262     {
 263       gdbpy_err_fetch fetched_error;
 264       gdb::unique_xmalloc_ptr<char> msg = fetched_error.to_string ();
 265
 266       if (msg == NULL || *msg == '\0')
 267         fprintf_styled (stream, metadata_style.style (),
 268                         _("<error reading variable>"));
 269       else
 270         fprintf_styled (stream, metadata_style.style (),
 271                         _("<error reading variable: %s>"), msg.get ());
 272     }
 273   else
 274     gdbpy_print_stack ();
 275 }
 276
 277 /* Helper for gdbpy_apply_val_pretty_printer which calls to_string and
 278    formats the result.  */
 279
 280 static enum gdbpy_string_repr_result
 281 print_string_repr (PyObject *printer, const char *hint,
 282                    struct ui_file *stream, int recurse,
 283                    const struct value_print_options *options,
 284                    const struct language_defn *language,
 285                    struct gdbarch *gdbarch)
 286 {
 287   struct value *replacement = NULL;
 288   enum gdbpy_string_repr_result result = string_repr_ok;
 289
 290   gdbpy_ref<> py_str = pretty_print_one_value (printer, &replacement);
 291   if (py_str != NULL)
 292     {
 293       if (py_str == Py_None)
 294         result = string_repr_none;
 295       else if (gdbpy_is_lazy_string (py_str.get ()))
 296         {
 297           CORE_ADDR addr;
 298           long length;
 299           struct type *type;
 300           gdb::unique_xmalloc_ptr<char> encoding;
 301           struct value_print_options local_opts = *options;
 302
 303           gdbpy_extract_lazy_string (py_str.get (), &addr, &type,
 304                                      &length, &encoding);
 305
 306           local_opts.addressprint = false;
 307           val_print_string (type, encoding.get (), addr, (int) length,
 308                             stream, &local_opts);
 309         }
 310       else
 311         {
 312           gdbpy_ref<> string
 313             = python_string_to_target_python_string (py_str.get ());
 314           if (string != NULL)
 315             {
 316               char *output;
 317               long length;
 318               struct type *type;
 319
 320               output = PyBytes_AS_STRING (string.get ());
 321               length = PyBytes_GET_SIZE (string.get ());
 322               type = builtin_type (gdbarch)->builtin_char;
 323
 324               if (hint && !strcmp (hint, "string"))
 325                 language->printstr (stream, type, (gdb_byte *) output,
 326                                     length, NULL, 0, options);
 327               else
 328                 gdb_puts (output, stream);
 329             }
 330           else
 331             {
 332               result = string_repr_error;
 333               print_stack_unless_memory_error (stream);
 334             }
 335         }
 336     }
 337   else if (replacement)
 338     {
 339       struct value_print_options opts = *options;
 340
 341       opts.addressprint = false;
 342       common_val_print (replacement, stream, recurse, &opts, language);
 343     }
 344   else
 345     {
 346       result = string_repr_error;
 347       print_stack_unless_memory_error (stream);
 348     }
 349
 350   return result;
 351 }
 352
 353 /* Helper for gdbpy_apply_val_pretty_printer that formats children of the
 354    printer, if any exist.  If is_py_none is true, then nothing has
 355    been printed by to_string, and format output accordingly. */
 356 static void
 357 print_children (PyObject *printer, const char *hint,
 358                 struct ui_file *stream, int recurse,
 359                 const struct value_print_options *options,
 360                 const struct language_defn *language,
 361                 int is_py_none)
 362 {
 363   int is_map, is_array, done_flag, pretty;
 364   unsigned int i;
 365
 366   if (! PyObject_HasAttr (printer, gdbpy_children_cst))
 367     return;
 368
 369   /* If we are printing a map or an array, we want some special
 370      formatting.  */
 371   is_map = hint && ! strcmp (hint, "map");
 372   is_array = hint && ! strcmp (hint, "array");
 373
 374   gdbpy_ref<> children (PyObject_CallMethodObjArgs (printer, gdbpy_children_cst,
 375                                                     NULL));
 376   if (children == NULL)
 377     {
 378       print_stack_unless_memory_error (stream);
 379       return;
 380     }
 381
 382   gdbpy_ref<> iter (PyObject_GetIter (children.get ()));
 383   if (iter == NULL)
 384     {
 385       print_stack_unless_memory_error (stream);
 386       return;
 387     }
 388
 389   /* Use the prettyformat_arrays option if we are printing an array,
 390      and the pretty option otherwise.  */
 391   if (is_array)
 392     pretty = options->prettyformat_arrays;
 393   else
 394     {
 395       if (options->prettyformat == Val_prettyformat)
 396         pretty = 1;
 397       else
 398         pretty = options->prettyformat_structs;
 399     }
 400
 401   done_flag = 0;
 402   for (i = 0; i < options->print_max; ++i)
 403     {
 404       PyObject *py_v;
 405       const char *name;
 406
 407       gdbpy_ref<> item (PyIter_Next (iter.get ()));
 408       if (item == NULL)
 409         {
 410           if (PyErr_Occurred ())
 411             print_stack_unless_memory_error (stream);
 412           /* Set a flag so we can know whether we printed all the
 413              available elements.  */
 414           else
 415             done_flag = 1;
 416           break;
 417         }
 418
 419       if (! PyTuple_Check (item.get ()) || PyTuple_Size (item.get ()) != 2)
 420         {
 421           PyErr_SetString (PyExc_TypeError,
 422                            _("Result of children iterator not a tuple"
 423                              " of two elements."));
 424           gdbpy_print_stack ();
 425           continue;
 426         }
 427       if (! PyArg_ParseTuple (item.get (), "sO", &name, &py_v))
 428         {
 429           /* The user won't necessarily get a stack trace here, so provide
 430              more context.  */
 431           if (gdbpy_print_python_errors_p ())
 432             gdb_printf (gdb_stderr,
 433                         _("Bad result from children iterator.\n"));
 434           gdbpy_print_stack ();
 435           continue;
 436         }
 437
 438       /* Print initial "=" to separate print_string_repr output and
 439          children.  For other elements, there are three cases:
 440          1. Maps.  Print a "," after each value element.
 441          2. Arrays.  Always print a ",".
 442          3. Other.  Always print a ",".  */
 443       if (i == 0)
 444         {
 445           if (!is_py_none)
 446             gdb_puts (" = ", stream);
 447         }
 448       else if (! is_map || i % 2 == 0)
 449         gdb_puts (pretty ? "," : ", ", stream);
 450
 451       /* Skip printing children if max_depth has been reached.  This check
 452          is performed after print_string_repr and the "=" separator so that
 453          these steps are not skipped if the variable is located within the
 454          permitted depth.  */
 455       if (val_print_check_max_depth (stream, recurse, options, language))
 456         return;
 457       else if (i == 0)
 458         /* Print initial "{" to bookend children.  */
 459         gdb_puts ("{", stream);
 460
 461       /* In summary mode, we just want to print "= {...}" if there is
 462          a value.  */
 463       if (options->summary)
 464         {
 465           /* This increment tricks the post-loop logic to print what
 466              we want.  */
 467           ++i;
 468           /* Likewise.  */
 469           pretty = 0;
 470           break;
 471         }
 472
 473       if (! is_map || i % 2 == 0)
 474         {
 475           if (pretty)
 476             {
 477               gdb_puts ("\n", stream);
 478               print_spaces (2 + 2 * recurse, stream);
 479             }
 480           else
 481             stream->wrap_here (2 + 2 *recurse);
 482         }
 483
 484       if (is_map && i % 2 == 0)
 485         gdb_puts ("[", stream);
 486       else if (is_array)
 487         {
 488           /* We print the index, not whatever the child method
 489              returned as the name.  */
 490           if (options->print_array_indexes)
 491             gdb_printf (stream, "[%d] = ", i);
 492         }
 493       else if (! is_map)
 494         {
 495           gdb_puts (name, stream);
 496           gdb_puts (" = ", stream);
 497         }
 498
 499       if (gdbpy_is_lazy_string (py_v))
 500         {
 501           CORE_ADDR addr;
 502           struct type *type;
 503           long length;
 504           gdb::unique_xmalloc_ptr<char> encoding;
 505           struct value_print_options local_opts = *options;
 506
 507           gdbpy_extract_lazy_string (py_v, &addr, &type, &length, &encoding);
 508
 509           local_opts.addressprint = false;
 510           val_print_string (type, encoding.get (), addr, (int) length, stream,
 511                             &local_opts);
 512         }
 513       else if (gdbpy_is_string (py_v))
 514         {
 515           gdb::unique_xmalloc_ptr<char> output;
 516
 517           output = python_string_to_host_string (py_v);
 518           if (!output)
 519             gdbpy_print_stack ();
 520           else
 521             gdb_puts (output.get (), stream);
 522         }
 523       else
 524         {
 525           struct value *value = convert_value_from_python (py_v);
 526
 527           if (value == NULL)
 528             {
 529               gdbpy_print_stack ();
 530               error (_("Error while executing Python code."));
 531             }
 532           else
 533             {
 534               /* When printing the key of a map we allow one additional
 535                  level of depth.  This means the key will print before the
 536                  value does.  */
 537               struct value_print_options opt = *options;
 538               if (is_map && i % 2 == 0
 539                   && opt.max_depth != -1
 540                   && opt.max_depth < INT_MAX)
 541                 ++opt.max_depth;
 542               common_val_print (value, stream, recurse + 1, &opt, language);
 543             }
 544         }
 545
 546       if (is_map && i % 2 == 0)
 547         gdb_puts ("] = ", stream);
 548     }
 549
 550   if (i)
 551     {
 552       if (!done_flag)
 553         {
 554           if (pretty)
 555             {
 556               gdb_puts ("\n", stream);
 557               print_spaces (2 + 2 * recurse, stream);
 558             }
 559           gdb_puts ("...", stream);
 560         }
 561       if (pretty)
 562         {
 563           gdb_puts ("\n", stream);
 564           print_spaces (2 * recurse, stream);
 565         }
 566       gdb_puts ("}", stream);
 567     }
 568 }
 569
 570 enum ext_lang_rc
 571 gdbpy_apply_val_pretty_printer (const struct extension_language_defn *extlang,
 572                                 struct value *value,
 573                                 struct ui_file *stream, int recurse,
 574                                 const struct value_print_options *options,
 575                                 const struct language_defn *language)
 576 {
 577   struct type *type = value_type (value);
 578   struct gdbarch *gdbarch = type->arch ();
 579   enum gdbpy_string_repr_result print_result;
 580
 581   if (value_lazy (value))
 582     value_fetch_lazy (value);
 583
 584   /* No pretty-printer support for unavailable values.  */
 585   if (!value_bytes_available (value, 0, type->length ()))
 586     return EXT_LANG_RC_NOP;
 587
 588   if (!gdb_python_initialized)
 589     return EXT_LANG_RC_NOP;
 590
 591   gdbpy_enter enter_py (gdbarch, language);
 592
 593   gdbpy_ref<> val_obj (value_to_value_object_no_release (value));
 594   if (val_obj == NULL)
 595     {
 596       print_stack_unless_memory_error (stream);
 597       return EXT_LANG_RC_ERROR;
 598     }
 599
 600   /* Find the constructor.  */
 601   gdbpy_ref<> printer (find_pretty_printer (val_obj.get ()));
 602   if (printer == NULL)
 603     {
 604       print_stack_unless_memory_error (stream);
 605       return EXT_LANG_RC_ERROR;
 606     }
 607
 608   if (printer == Py_None)
 609     return EXT_LANG_RC_NOP;
 610
 611   scoped_restore set_options = make_scoped_restore (&gdbpy_current_print_options,
 612                                                     options);
 613
 614   /* If we are printing a map, we want some special formatting.  */
 615   gdb::unique_xmalloc_ptr<char> hint (gdbpy_get_display_hint (printer.get ()));
 616
 617   /* Print the section */
 618   print_result = print_string_repr (printer.get (), hint.get (), stream,
 619                                     recurse, options, language, gdbarch);
 620   if (print_result != string_repr_error)
 621     print_children (printer.get (), hint.get (), stream, recurse, options,
 622                     language, print_result == string_repr_none);
 623
 624   if (PyErr_Occurred ())
 625     print_stack_unless_memory_error (stream);
 626   return EXT_LANG_RC_OK;
 627 }
 628
 629
 630 /* Apply a pretty-printer for the varobj code.  PRINTER_OBJ is the
 631    print object.  It must have a 'to_string' method (but this is
 632    checked by varobj, not here) which takes no arguments and
 633    returns a string.  The printer will return a value and in the case
 634    of a Python string being returned, this function will return a
 635    PyObject containing the string.  For any other type, *REPLACEMENT is
 636    set to the replacement value and this function returns NULL.  On
 637    error, *REPLACEMENT is set to NULL and this function also returns
 638    NULL.  */
 639 gdbpy_ref<>
 640 apply_varobj_pretty_printer (PyObject *printer_obj,
 641                              struct value **replacement,
 642                              struct ui_file *stream,
 643                              const value_print_options *opts)
 644 {
 645   scoped_restore set_options = make_scoped_restore (&gdbpy_current_print_options,
 646                                                     opts);
 647
 648   *replacement = NULL;
 649   gdbpy_ref<> py_str = pretty_print_one_value (printer_obj, replacement);
 650
 651   if (*replacement == NULL && py_str == NULL)
 652     print_stack_unless_memory_error (stream);
 653
 654   return py_str;
 655 }
 656
 657 /* Find a pretty-printer object for the varobj module.  Returns a new
 658    reference to the object if successful; returns NULL if not.  VALUE
 659    is the value for which a printer tests to determine if it
 660    can pretty-print the value.  */
 661 gdbpy_ref<>
 662 gdbpy_get_varobj_pretty_printer (struct value *value)
 663 {
 664   try
 665     {
 666       value = value_copy (value);
 667     }
 668   catch (const gdb_exception &except)
 669     {
 670       GDB_PY_HANDLE_EXCEPTION (except);
 671     }
 672
 673   gdbpy_ref<> val_obj (value_to_value_object (value));
 674   if (val_obj == NULL)
 675     return NULL;
 676
 677   return find_pretty_printer (val_obj.get ());
 678 }
 679
 680 /* A Python function which wraps find_pretty_printer and instantiates
 681    the resulting class.  This accepts a Value argument and returns a
 682    pretty printer instance, or None.  This function is useful as an
 683    argument to the MI command -var-set-visualizer.  */
 684 PyObject *
 685 gdbpy_default_visualizer (PyObject *self, PyObject *args)
 686 {
 687   PyObject *val_obj;
 688   struct value *value;
 689
 690   if (! PyArg_ParseTuple (args, "O", &val_obj))
 691     return NULL;
 692   value = value_object_to_value (val_obj);
 693   if (! value)
 694     {
 695       PyErr_SetString (PyExc_TypeError,
 696                        _("Argument must be a gdb.Value."));
 697       return NULL;
 698     }
 699
 700   return find_pretty_printer (val_obj).release ();
 701 }
 702
 703 /* Helper function to set a boolean in a dictionary.  */
 704 static int
 705 set_boolean (PyObject *dict, const char *name, bool val)
 706 {
 707   gdbpy_ref<> val_obj (PyBool_FromLong (val));
 708   if (val_obj == nullptr)
 709     return -1;
 710   return PyDict_SetItemString (dict, name, val_obj.get ());
 711 }
 712
 713 /* Helper function to set an integer in a dictionary.  */
 714 static int
 715 set_unsigned (PyObject *dict, const char *name, unsigned int val)
 716 {
 717   gdbpy_ref<> val_obj = gdb_py_object_from_ulongest (val);
 718   if (val_obj == nullptr)
 719     return -1;
 720   return PyDict_SetItemString (dict, name, val_obj.get ());
 721 }
 722
 723 /* Implement gdb.print_options.  */
 724 PyObject *
 725 gdbpy_print_options (PyObject *unused1, PyObject *unused2)
 726 {
 727   gdbpy_ref<> result (PyDict_New ());
 728   if (result == nullptr)
 729     return nullptr;
 730
 731   value_print_options opts;
 732   gdbpy_get_print_options (&opts);
 733
 734   if (set_boolean (result.get (), "raw",
 735                    opts.raw) < 0
 736       || set_boolean (result.get (), "pretty_arrays",
 737                       opts.prettyformat_arrays) < 0
 738       || set_boolean (result.get (), "pretty_structs",
 739                       opts.prettyformat_structs) < 0
 740       || set_boolean (result.get (), "array_indexes",
 741                       opts.print_array_indexes) < 0
 742       || set_boolean (result.get (), "symbols",
 743                       opts.symbol_print) < 0
 744       || set_boolean (result.get (), "unions",
 745                       opts.unionprint) < 0
 746       || set_boolean (result.get (), "address",
 747                       opts.addressprint) < 0
 748       || set_boolean (result.get (), "deref_refs",
 749                       opts.deref_ref) < 0
 750       || set_boolean (result.get (), "actual_objects",
 751                       opts.objectprint) < 0
 752       || set_boolean (result.get (), "static_members",
 753                       opts.static_field_print) < 0
 754       || set_boolean (result.get (), "deref_refs",
 755                       opts.deref_ref) < 0
 756       || set_boolean (result.get (), "nibbles",
 757                       opts.nibblesprint) < 0
 758       || set_boolean (result.get (), "summary",
 759                       opts.summary) < 0
 760       || set_unsigned (result.get (), "max_elements",
 761                        opts.print_max) < 0
 762       || set_unsigned (result.get (), "max_depth",
 763                        opts.max_depth) < 0
 764       || set_unsigned (result.get (), "repeat_threshold",
 765                        opts.repeat_count_threshold) < 0)
 766     return nullptr;
 767
 768   if (opts.format != 0)
 769     {
 770       char str[2] = { (char) opts.format, 0 };
 771       gdbpy_ref<> fmtstr = host_string_to_python_string (str);
 772       if (fmtstr == nullptr)
 773         return nullptr;
 774       if (PyDict_SetItemString (result.get (), "format", fmtstr.get ()) < 0)
 775         return nullptr;
 776     }
 777
 778   return result.release ();
 779 }
 780
 781 /* Helper function that either finds the prevailing print options, or
 782    calls get_user_print_options.  */
 783 void
 784 gdbpy_get_print_options (value_print_options *opts)
 785 {
 786   if (gdbpy_current_print_options != nullptr)
 787     *opts = *gdbpy_current_print_options;
 788   else
 789     get_user_print_options (opts);
 790 }