gcc/diagnostic-format-json.cc

   1 /* JSON output for diagnostics
   2    Copyright (C) 2018-2020 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 /* The top-level JSON array of pending diagnostics.  */
  32
  33 static json::array *toplevel_array;
  34
  35 /* The JSON object for the current diagnostic group.  */
  36
  37 static json::object *cur_group;
  38
  39 /* The JSON array for the "children" array within the current diagnostic
  40    group.  */
  41
  42 static json::array *cur_children_array;
  43
  44 /* Generate a JSON object for LOC.  */
  45
  46 json::value *
  47 json_from_expanded_location (diagnostic_context *context, location_t loc)
  48 {
  49   expanded_location exploc = expand_location (loc);
  50   json::object *result = new json::object ();
  51   if (exploc.file)
  52     result->set ("file", new json::string (exploc.file));
  53   result->set ("line", new json::integer_number (exploc.line));
  54
  55   const enum diagnostics_column_unit orig_unit = context->column_unit;
  56   struct
  57   {
  58     const char *name;
  59     enum diagnostics_column_unit unit;
  60   } column_fields[] = {
  61     {"display-column", DIAGNOSTICS_COLUMN_UNIT_DISPLAY},
  62     {"byte-column", DIAGNOSTICS_COLUMN_UNIT_BYTE}
  63   };
  64   int the_column = INT_MIN;
  65   for (int i = 0; i != sizeof column_fields / sizeof (*column_fields); ++i)
  66     {
  67       context->column_unit = column_fields[i].unit;
  68       const int col = diagnostic_converted_column (context, exploc);
  69       result->set (column_fields[i].name, new json::integer_number (col));
  70       if (column_fields[i].unit == orig_unit)
  71         the_column = col;
  72     }
  73   gcc_assert (the_column != INT_MIN);
  74   result->set ("column", new json::integer_number (the_column));
  75   context->column_unit = orig_unit;
  76   return result;
  77 }
  78
  79 /* Generate a JSON object for LOC_RANGE.  */
  80
  81 static json::object *
  82 json_from_location_range (diagnostic_context *context,
  83                           const location_range *loc_range, unsigned range_idx)
  84 {
  85   location_t caret_loc = get_pure_location (loc_range->m_loc);
  86
  87   if (caret_loc == UNKNOWN_LOCATION)
  88     return NULL;
  89
  90   location_t start_loc = get_start (loc_range->m_loc);
  91   location_t finish_loc = get_finish (loc_range->m_loc);
  92
  93   json::object *result = new json::object ();
  94   result->set ("caret", json_from_expanded_location (context, caret_loc));
  95   if (start_loc != caret_loc
  96       && start_loc != UNKNOWN_LOCATION)
  97     result->set ("start", json_from_expanded_location (context, start_loc));
  98   if (finish_loc != caret_loc
  99       && finish_loc != UNKNOWN_LOCATION)
 100     result->set ("finish", json_from_expanded_location (context, finish_loc));
 101
 102   if (loc_range->m_label)
 103     {
 104       label_text text;
 105       text = loc_range->m_label->get_text (range_idx);
 106       if (text.m_buffer)
 107         result->set ("label", new json::string (text.m_buffer));
 108       text.maybe_free ();
 109     }
 110
 111   return result;
 112 }
 113
 114 /* Generate a JSON object for HINT.  */
 115
 116 static json::object *
 117 json_from_fixit_hint (diagnostic_context *context, const fixit_hint *hint)
 118 {
 119   json::object *fixit_obj = new json::object ();
 120
 121   location_t start_loc = hint->get_start_loc ();
 122   fixit_obj->set ("start", json_from_expanded_location (context, start_loc));
 123   location_t next_loc = hint->get_next_loc ();
 124   fixit_obj->set ("next", json_from_expanded_location (context, next_loc));
 125   fixit_obj->set ("string", new json::string (hint->get_string ()));
 126
 127   return fixit_obj;
 128 }
 129
 130 /* Generate a JSON object for METADATA.  */
 131
 132 static json::object *
 133 json_from_metadata (const diagnostic_metadata *metadata)
 134 {
 135   json::object *metadata_obj = new json::object ();
 136
 137   if (metadata->get_cwe ())
 138     metadata_obj->set ("cwe",
 139                        new json::integer_number (metadata->get_cwe ()));
 140
 141   return metadata_obj;
 142 }
 143
 144 /* No-op implementation of "begin_diagnostic" for JSON output.  */
 145
 146 static void
 147 json_begin_diagnostic (diagnostic_context *, diagnostic_info *)
 148 {
 149 }
 150
 151 /* Implementation of "end_diagnostic" for JSON output.
 152    Generate a JSON object for DIAGNOSTIC, and store for output
 153    within current diagnostic group.  */
 154
 155 static void
 156 json_end_diagnostic (diagnostic_context *context, diagnostic_info *diagnostic,
 157                      diagnostic_t orig_diag_kind)
 158 {
 159   json::object *diag_obj = new json::object ();
 160
 161   /* Get "kind" of diagnostic.  */
 162   {
 163     static const char *const diagnostic_kind_text[] = {
 164 #define DEFINE_DIAGNOSTIC_KIND(K, T, C) (T),
 165 #include "diagnostic.def"
 166 #undef DEFINE_DIAGNOSTIC_KIND
 167       "must-not-happen"
 168     };
 169     /* Lose the trailing ": ".  */
 170     const char *kind_text = diagnostic_kind_text[diagnostic->kind];
 171     size_t len = strlen (kind_text);
 172     gcc_assert (len > 2);
 173     gcc_assert (kind_text[len - 2] == ':');
 174     gcc_assert (kind_text[len - 1] == ' ');
 175     char *rstrip = xstrdup (kind_text);
 176     rstrip[len - 2] = '\0';
 177     diag_obj->set ("kind", new json::string (rstrip));
 178     free (rstrip);
 179   }
 180
 181   // FIXME: encoding of the message (json::string requires UTF-8)
 182   diag_obj->set ("message",
 183                  new json::string (pp_formatted_text (context->printer)));
 184   pp_clear_output_area (context->printer);
 185
 186   char *option_text;
 187   option_text = context->option_name (context, diagnostic->option_index,
 188                                       orig_diag_kind, diagnostic->kind);
 189   if (option_text)
 190     {
 191       diag_obj->set ("option", new json::string (option_text));
 192       free (option_text);
 193     }
 194
 195   if (context->get_option_url)
 196     {
 197       char *option_url = context->get_option_url (context,
 198                                                   diagnostic->option_index);
 199       if (option_url)
 200         {
 201           diag_obj->set ("option_url", new json::string (option_url));
 202           free (option_url);
 203         }
 204     }
 205
 206   /* If we've already emitted a diagnostic within this auto_diagnostic_group,
 207      then add diag_obj to its "children" array.  */
 208   if (cur_group)
 209     {
 210       gcc_assert (cur_children_array);
 211       cur_children_array->append (diag_obj);
 212     }
 213   else
 214     {
 215       /* Otherwise, make diag_obj be the top-level object within the group;
 216          add a "children" array and record the column origin.  */
 217       toplevel_array->append (diag_obj);
 218       cur_group = diag_obj;
 219       cur_children_array = new json::array ();
 220       diag_obj->set ("children", cur_children_array);
 221       diag_obj->set ("column-origin",
 222                      new json::integer_number (context->column_origin));
 223     }
 224
 225   const rich_location *richloc = diagnostic->richloc;
 226
 227   json::array *loc_array = new json::array ();
 228   diag_obj->set ("locations", loc_array);
 229
 230   for (unsigned int i = 0; i < richloc->get_num_locations (); i++)
 231     {
 232       const location_range *loc_range = richloc->get_range (i);
 233       json::object *loc_obj = json_from_location_range (context, loc_range, i);
 234       if (loc_obj)
 235         loc_array->append (loc_obj);
 236     }
 237
 238   if (richloc->get_num_fixit_hints ())
 239     {
 240       json::array *fixit_array = new json::array ();
 241       diag_obj->set ("fixits", fixit_array);
 242       for (unsigned int i = 0; i < richloc->get_num_fixit_hints (); i++)
 243         {
 244           const fixit_hint *hint = richloc->get_fixit_hint (i);
 245           json::object *fixit_obj = json_from_fixit_hint (context, hint);
 246           fixit_array->append (fixit_obj);
 247         }
 248     }
 249
 250   /* TODO: tree-ish things:
 251      TODO: functions
 252      TODO: inlining information
 253      TODO: macro expansion information.  */
 254
 255   if (diagnostic->metadata)
 256     {
 257       json::object *metadata_obj = json_from_metadata (diagnostic->metadata);
 258       diag_obj->set ("metadata", metadata_obj);
 259     }
 260
 261   const diagnostic_path *path = richloc->get_path ();
 262   if (path && context->make_json_for_path)
 263     {
 264       json::value *path_value = context->make_json_for_path (context, path);
 265       diag_obj->set ("path", path_value);
 266     }
 267 }
 268
 269 /* No-op implementation of "begin_group_cb" for JSON output.  */
 270
 271 static void
 272 json_begin_group (diagnostic_context *)
 273 {
 274 }
 275
 276 /* Implementation of "end_group_cb" for JSON output.  */
 277
 278 static void
 279 json_end_group (diagnostic_context *)
 280 {
 281   cur_group = NULL;
 282   cur_children_array = NULL;
 283 }
 284
 285 /* Callback for final cleanup for JSON output.  */
 286
 287 static void
 288 json_final_cb (diagnostic_context *)
 289 {
 290   /* Flush the top-level array.  */
 291   toplevel_array->dump (stderr);
 292   fprintf (stderr, "\n");
 293   delete toplevel_array;
 294   toplevel_array = NULL;
 295 }
 296
 297 /* Set the output format for CONTEXT to FORMAT.  */
 298
 299 void
 300 diagnostic_output_format_init (diagnostic_context *context,
 301                                enum diagnostics_output_format format)
 302 {
 303   switch (format)
 304     {
 305     default:
 306       gcc_unreachable ();
 307     case DIAGNOSTICS_OUTPUT_FORMAT_TEXT:
 308       /* The default; do nothing.  */
 309       break;
 310
 311     case DIAGNOSTICS_OUTPUT_FORMAT_JSON:
 312       {
 313         /* Set up top-level JSON array.  */
 314         if (toplevel_array == NULL)
 315           toplevel_array = new json::array ();
 316
 317         /* Override callbacks.  */
 318         context->begin_diagnostic = json_begin_diagnostic;
 319         context->end_diagnostic = json_end_diagnostic;
 320         context->begin_group_cb = json_begin_group;
 321         context->end_group_cb =  json_end_group;
 322         context->final_cb =  json_final_cb;
 323         context->print_path = NULL; /* handled in json_end_diagnostic.  */
 324
 325         /* The metadata is handled in JSON format, rather than as text.  */
 326         context->show_cwe = false;
 327
 328         /* The option is handled in JSON format, rather than as text.  */
 329         context->show_option_requested = false;
 330
 331         /* Don't colorize the text.  */
 332         pp_show_color (context->printer) = false;
 333       }
 334       break;
 335     }
 336 }
 337
 338 #if CHECKING_P
 339
 340 namespace selftest {
 341
 342 /* We shouldn't call json_from_expanded_location on UNKNOWN_LOCATION,
 343    but verify that we handle this gracefully.  */
 344
 345 static void
 346 test_unknown_location ()
 347 {
 348   test_diagnostic_context dc;
 349   delete json_from_expanded_location (&dc, UNKNOWN_LOCATION);
 350 }
 351
 352 /* Verify that we gracefully handle attempts to serialize bad
 353    compound locations.  */
 354
 355 static void
 356 test_bad_endpoints ()
 357 {
 358   location_t bad_endpoints
 359     = make_location (BUILTINS_LOCATION,
 360                      UNKNOWN_LOCATION, UNKNOWN_LOCATION);
 361
 362   location_range loc_range;
 363   loc_range.m_loc = bad_endpoints;
 364   loc_range.m_range_display_kind = SHOW_RANGE_WITH_CARET;
 365   loc_range.m_label = NULL;
 366
 367   test_diagnostic_context dc;
 368   json::object *obj = json_from_location_range (&dc, &loc_range, 0);
 369   /* We should have a "caret" value, but no "start" or "finish" values.  */
 370   ASSERT_TRUE (obj != NULL);
 371   ASSERT_TRUE (obj->get ("caret") != NULL);
 372   ASSERT_TRUE (obj->get ("start") == NULL);
 373   ASSERT_TRUE (obj->get ("finish") == NULL);
 374   delete obj;
 375 }
 376
 377 /* Run all of the selftests within this file.  */
 378
 379 void
 380 diagnostic_format_json_cc_tests ()
 381 {
 382   test_unknown_location ();
 383   test_bad_endpoints ();
 384 }
 385
 386 } // namespace selftest
 387
 388 #endif /* #if CHECKING_P */