gcc/diagnostic-format-json.cc

   1 /* JSON output for diagnostics
   2    Copyright (C) 2018-2024 Free Software Foundation, Inc.
   3    Contributed by David Malcolm <dmalcolm@redhat.com>.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "diagnostic.h"
  26 #include "selftest-diagnostic.h"
  27 #include "diagnostic-metadata.h"
  28 #include "json.h"
  29 #include "selftest.h"
  30
  31 /* Subclass of diagnostic_output_format for JSON output.  */
  32
  33 class json_output_format : public diagnostic_output_format
  34 {
  35 public:
  36   void on_begin_group () final override
  37   {
  38     /* No-op.  */
  39   }
  40   void on_end_group () final override
  41   {
  42     m_cur_group = nullptr;
  43     m_cur_children_array = nullptr;
  44   }
  45   void
  46   on_begin_diagnostic (const diagnostic_info &) final override
  47   {
  48     /* No-op.  */
  49   }
  50   void
  51   on_end_diagnostic (const diagnostic_info &diagnostic,
  52                      diagnostic_t orig_diag_kind) final override;
  53   void on_diagram (const diagnostic_diagram &) final override
  54   {
  55     /* No-op.  */
  56   }
  57
  58 protected:
  59   json_output_format (diagnostic_context &context,
  60                       bool formatted)
  61   : diagnostic_output_format (context),
  62     m_toplevel_array (new json::array ()),
  63     m_cur_group (nullptr),
  64     m_cur_children_array (nullptr),
  65     m_formatted (formatted)
  66   {
  67   }
  68
  69   /* Flush the top-level array to OUTF.  */
  70   void
  71   flush_to_file (FILE *outf)
  72   {
  73     m_toplevel_array->dump (outf, m_formatted);
  74     fprintf (outf, "\n");
  75     delete m_toplevel_array;
  76     m_toplevel_array = nullptr;
  77   }
  78
  79 private:
  80   /* The top-level JSON array of pending diagnostics.  */
  81   json::array *m_toplevel_array;
  82
  83   /* The JSON object for the current diagnostic group.  */
  84   json::object *m_cur_group;
  85
  86   /* The JSON array for the "children" array within the current diagnostic
  87      group.  */
  88   json::array *m_cur_children_array;
  89
  90   bool m_formatted;
  91 };
  92
  93 /* Generate a JSON object for LOC.  */
  94
  95 json::value *
  96 json_from_expanded_location (diagnostic_context *context, location_t loc)
  97 {
  98   expanded_location exploc = expand_location (loc);
  99   json::object *result = new json::object ();
 100   if (exploc.file)
 101     result->set_string ("file", exploc.file);
 102   result->set_integer ("line", exploc.line);
 103
 104   const enum diagnostics_column_unit orig_unit = context->m_column_unit;
 105   struct
 106   {
 107     const char *name;
 108     enum diagnostics_column_unit unit;
 109   } column_fields[] = {
 110     {"display-column", DIAGNOSTICS_COLUMN_UNIT_DISPLAY},
 111     {"byte-column", DIAGNOSTICS_COLUMN_UNIT_BYTE}
 112   };
 113   int the_column = INT_MIN;
 114   for (int i = 0; i != ARRAY_SIZE (column_fields); ++i)
 115     {
 116       context->m_column_unit = column_fields[i].unit;
 117       const int col = context->converted_column (exploc);
 118       result->set_integer (column_fields[i].name, col);
 119       if (column_fields[i].unit == orig_unit)
 120         the_column = col;
 121     }
 122   gcc_assert (the_column != INT_MIN);
 123   result->set_integer ("column", the_column);
 124   context->m_column_unit = orig_unit;
 125   return result;
 126 }
 127
 128 /* Generate a JSON object for LOC_RANGE.  */
 129
 130 static json::object *
 131 json_from_location_range (diagnostic_context *context,
 132                           const location_range *loc_range, unsigned range_idx)
 133 {
 134   location_t caret_loc = get_pure_location (loc_range->m_loc);
 135
 136   if (caret_loc == UNKNOWN_LOCATION)
 137     return NULL;
 138
 139   location_t start_loc = get_start (loc_range->m_loc);
 140   location_t finish_loc = get_finish (loc_range->m_loc);
 141
 142   json::object *result = new json::object ();
 143   result->set ("caret", json_from_expanded_location (context, caret_loc));
 144   if (start_loc != caret_loc
 145       && start_loc != UNKNOWN_LOCATION)
 146     result->set ("start", json_from_expanded_location (context, start_loc));
 147   if (finish_loc != caret_loc
 148       && finish_loc != UNKNOWN_LOCATION)
 149     result->set ("finish", json_from_expanded_location (context, finish_loc));
 150
 151   if (loc_range->m_label)
 152     {
 153       label_text text (loc_range->m_label->get_text (range_idx));
 154       if (text.get ())
 155         result->set_string ("label", text.get ());
 156     }
 157
 158   return result;
 159 }
 160
 161 /* Generate a JSON object for HINT.  */
 162
 163 static json::object *
 164 json_from_fixit_hint (diagnostic_context *context, const fixit_hint *hint)
 165 {
 166   json::object *fixit_obj = new json::object ();
 167
 168   location_t start_loc = hint->get_start_loc ();
 169   fixit_obj->set ("start", json_from_expanded_location (context, start_loc));
 170   location_t next_loc = hint->get_next_loc ();
 171   fixit_obj->set ("next", json_from_expanded_location (context, next_loc));
 172   fixit_obj->set_string ("string", hint->get_string ());
 173
 174   return fixit_obj;
 175 }
 176
 177 /* Generate a JSON object for METADATA.  */
 178
 179 static json::object *
 180 json_from_metadata (const diagnostic_metadata *metadata)
 181 {
 182   json::object *metadata_obj = new json::object ();
 183
 184   if (metadata->get_cwe ())
 185     metadata_obj->set_integer ("cwe", metadata->get_cwe ());
 186
 187   return metadata_obj;
 188 }
 189
 190 /* Implementation of "on_end_diagnostic" vfunc for JSON output.
 191    Generate a JSON object for DIAGNOSTIC, and store for output
 192    within current diagnostic group.  */
 193
 194 void
 195 json_output_format::on_end_diagnostic (const diagnostic_info &diagnostic,
 196                                        diagnostic_t orig_diag_kind)
 197 {
 198   json::object *diag_obj = new json::object ();
 199
 200   /* Get "kind" of diagnostic.  */
 201   {
 202     static const char *const diagnostic_kind_text[] = {
 203 #define DEFINE_DIAGNOSTIC_KIND(K, T, C) (T),
 204 #include "diagnostic.def"
 205 #undef DEFINE_DIAGNOSTIC_KIND
 206       "must-not-happen"
 207     };
 208     /* Lose the trailing ": ".  */
 209     const char *kind_text = diagnostic_kind_text[diagnostic.kind];
 210     size_t len = strlen (kind_text);
 211     gcc_assert (len > 2);
 212     gcc_assert (kind_text[len - 2] == ':');
 213     gcc_assert (kind_text[len - 1] == ' ');
 214     char *rstrip = xstrdup (kind_text);
 215     rstrip[len - 2] = '\0';
 216     diag_obj->set_string ("kind", rstrip);
 217     free (rstrip);
 218   }
 219
 220   // FIXME: encoding of the message (json::string requires UTF-8)
 221   diag_obj->set_string ("message", pp_formatted_text (m_context.printer));
 222   pp_clear_output_area (m_context.printer);
 223
 224   if (char *option_text = m_context.make_option_name (diagnostic.option_index,
 225                                                       orig_diag_kind,
 226                                                       diagnostic.kind))
 227     {
 228       diag_obj->set_string ("option", option_text);
 229       free (option_text);
 230     }
 231
 232   if (char *option_url = m_context.make_option_url (diagnostic.option_index))
 233     {
 234       diag_obj->set_string ("option_url", option_url);
 235       free (option_url);
 236     }
 237
 238   /* If we've already emitted a diagnostic within this auto_diagnostic_group,
 239      then add diag_obj to its "children" array.  */
 240   if (m_cur_group)
 241     {
 242       gcc_assert (m_cur_children_array);
 243       m_cur_children_array->append (diag_obj);
 244     }
 245   else
 246     {
 247       /* Otherwise, make diag_obj be the top-level object within the group;
 248          add a "children" array and record the column origin.  */
 249       m_toplevel_array->append (diag_obj);
 250       m_cur_group = diag_obj;
 251       m_cur_children_array = new json::array ();
 252       diag_obj->set ("children", m_cur_children_array);
 253       diag_obj->set_integer ("column-origin", m_context.m_column_origin);
 254     }
 255
 256   const rich_location *richloc = diagnostic.richloc;
 257
 258   json::array *loc_array = new json::array ();
 259   diag_obj->set ("locations", loc_array);
 260
 261   for (unsigned int i = 0; i < richloc->get_num_locations (); i++)
 262     {
 263       const location_range *loc_range = richloc->get_range (i);
 264       json::object *loc_obj
 265         = json_from_location_range (&m_context, loc_range, i);
 266       if (loc_obj)
 267         loc_array->append (loc_obj);
 268     }
 269
 270   if (richloc->get_num_fixit_hints ())
 271     {
 272       json::array *fixit_array = new json::array ();
 273       diag_obj->set ("fixits", fixit_array);
 274       for (unsigned int i = 0; i < richloc->get_num_fixit_hints (); i++)
 275         {
 276           const fixit_hint *hint = richloc->get_fixit_hint (i);
 277           json::object *fixit_obj = json_from_fixit_hint (&m_context, hint);
 278           fixit_array->append (fixit_obj);
 279         }
 280     }
 281
 282   /* TODO: tree-ish things:
 283      TODO: functions
 284      TODO: inlining information
 285      TODO: macro expansion information.  */
 286
 287   if (diagnostic.metadata)
 288     {
 289       json::object *metadata_obj = json_from_metadata (diagnostic.metadata);
 290       diag_obj->set ("metadata", metadata_obj);
 291     }
 292
 293   const diagnostic_path *path = richloc->get_path ();
 294   if (path && m_context.m_make_json_for_path)
 295     {
 296       json::value *path_value
 297         = m_context.m_make_json_for_path (&m_context, path);
 298       diag_obj->set ("path", path_value);
 299     }
 300
 301   diag_obj->set ("escape-source",
 302                  new json::literal (richloc->escape_on_output_p ()));
 303 }
 304
 305 class json_stderr_output_format : public json_output_format
 306 {
 307 public:
 308   json_stderr_output_format (diagnostic_context &context,
 309                              bool formatted)
 310     : json_output_format (context, formatted)
 311   {
 312   }
 313   ~json_stderr_output_format ()
 314   {
 315     flush_to_file (stderr);
 316   }
 317 };
 318
 319 class json_file_output_format : public json_output_format
 320 {
 321 public:
 322   json_file_output_format (diagnostic_context &context,
 323                            bool formatted,
 324                            const char *base_file_name)
 325   : json_output_format (context, formatted),
 326     m_base_file_name (xstrdup (base_file_name))
 327   {
 328   }
 329
 330   ~json_file_output_format ()
 331   {
 332     char *filename = concat (m_base_file_name, ".gcc.json", NULL);
 333     free (m_base_file_name);
 334     m_base_file_name = nullptr;
 335     FILE *outf = fopen (filename, "w");
 336     if (!outf)
 337       {
 338         const char *errstr = xstrerror (errno);
 339         fnotice (stderr, "error: unable to open '%s' for writing: %s\n",
 340                  filename, errstr);
 341         free (filename);
 342         return;
 343       }
 344     flush_to_file (outf);
 345     fclose (outf);
 346     free (filename);
 347   }
 348
 349 private:
 350   char *m_base_file_name;
 351 };
 352
 353 /* Populate CONTEXT in preparation for JSON output (either to stderr, or
 354    to a file).  */
 355
 356 static void
 357 diagnostic_output_format_init_json (diagnostic_context *context)
 358 {
 359   /* Override callbacks.  */
 360   context->m_print_path = nullptr; /* handled in json_end_diagnostic.  */
 361
 362   /* The metadata is handled in JSON format, rather than as text.  */
 363   context->set_show_cwe (false);
 364   context->set_show_rules (false);
 365
 366   /* The option is handled in JSON format, rather than as text.  */
 367   context->set_show_option_requested (false);
 368
 369   /* Don't colorize the text.  */
 370   pp_show_color (context->printer) = false;
 371 }
 372
 373 /* Populate CONTEXT in preparation for JSON output to stderr.  */
 374
 375 void
 376 diagnostic_output_format_init_json_stderr (diagnostic_context *context,
 377                                            bool formatted)
 378 {
 379   diagnostic_output_format_init_json (context);
 380   context->set_output_format (new json_stderr_output_format (*context,
 381                                                              formatted));
 382 }
 383
 384 /* Populate CONTEXT in preparation for JSON output to a file named
 385    BASE_FILE_NAME.gcc.json.  */
 386
 387 void
 388 diagnostic_output_format_init_json_file (diagnostic_context *context,
 389                                          bool formatted,
 390                                          const char *base_file_name)
 391 {
 392   diagnostic_output_format_init_json (context);
 393   context->set_output_format (new json_file_output_format (*context,
 394                                                            formatted,
 395                                                            base_file_name));
 396 }
 397
 398 #if CHECKING_P
 399
 400 namespace selftest {
 401
 402 /* We shouldn't call json_from_expanded_location on UNKNOWN_LOCATION,
 403    but verify that we handle this gracefully.  */
 404
 405 static void
 406 test_unknown_location ()
 407 {
 408   test_diagnostic_context dc;
 409   delete json_from_expanded_location (&dc, UNKNOWN_LOCATION);
 410 }
 411
 412 /* Verify that we gracefully handle attempts to serialize bad
 413    compound locations.  */
 414
 415 static void
 416 test_bad_endpoints ()
 417 {
 418   location_t bad_endpoints
 419     = make_location (BUILTINS_LOCATION,
 420                      UNKNOWN_LOCATION, UNKNOWN_LOCATION);
 421
 422   location_range loc_range;
 423   loc_range.m_loc = bad_endpoints;
 424   loc_range.m_range_display_kind = SHOW_RANGE_WITH_CARET;
 425   loc_range.m_label = NULL;
 426
 427   test_diagnostic_context dc;
 428   json::object *obj = json_from_location_range (&dc, &loc_range, 0);
 429   /* We should have a "caret" value, but no "start" or "finish" values.  */
 430   ASSERT_TRUE (obj != NULL);
 431   ASSERT_TRUE (obj->get ("caret") != NULL);
 432   ASSERT_TRUE (obj->get ("start") == NULL);
 433   ASSERT_TRUE (obj->get ("finish") == NULL);
 434   delete obj;
 435 }
 436
 437 /* Run all of the selftests within this file.  */
 438
 439 void
 440 diagnostic_format_json_cc_tests ()
 441 {
 442   test_unknown_location ();
 443   test_bad_endpoints ();
 444 }
 445
 446 } // namespace selftest
 447
 448 #endif /* #if CHECKING_P */