gcc/diagnostic-format-json.cc

   1 /* JSON output for diagnostics
   2    Copyright (C) 2018-2023 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 (diagnostic_info *) final override
  47   {
  48     /* No-op.  */
  49   }
  50   void
  51   on_end_diagnostic (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   : diagnostic_output_format (context),
  61     m_toplevel_array (new json::array ()),
  62     m_cur_group (nullptr),
  63     m_cur_children_array (nullptr)
  64   {
  65   }
  66
  67   /* Flush the top-level array to OUTF.  */
  68   void
  69   flush_to_file (FILE *outf)
  70   {
  71     m_toplevel_array->dump (outf);
  72     fprintf (outf, "\n");
  73     delete m_toplevel_array;
  74     m_toplevel_array = nullptr;
  75   }
  76
  77 private:
  78   /* The top-level JSON array of pending diagnostics.  */
  79   json::array *m_toplevel_array;
  80
  81   /* The JSON object for the current diagnostic group.  */
  82   json::object *m_cur_group;
  83
  84   /* The JSON array for the "children" array within the current diagnostic
  85      group.  */
  86   json::array *m_cur_children_array;
  87 };
  88
  89 /* Generate a JSON object for LOC.  */
  90
  91 json::value *
  92 json_from_expanded_location (diagnostic_context *context, location_t loc)
  93 {
  94   expanded_location exploc = expand_location (loc);
  95   json::object *result = new json::object ();
  96   if (exploc.file)
  97     result->set ("file", new json::string (exploc.file));
  98   result->set ("line", new json::integer_number (exploc.line));
  99
 100   const enum diagnostics_column_unit orig_unit = context->m_column_unit;
 101   struct
 102   {
 103     const char *name;
 104     enum diagnostics_column_unit unit;
 105   } column_fields[] = {
 106     {"display-column", DIAGNOSTICS_COLUMN_UNIT_DISPLAY},
 107     {"byte-column", DIAGNOSTICS_COLUMN_UNIT_BYTE}
 108   };
 109   int the_column = INT_MIN;
 110   for (int i = 0; i != ARRAY_SIZE (column_fields); ++i)
 111     {
 112       context->m_column_unit = column_fields[i].unit;
 113       const int col = context->converted_column (exploc);
 114       result->set (column_fields[i].name, new json::integer_number (col));
 115       if (column_fields[i].unit == orig_unit)
 116         the_column = col;
 117     }
 118   gcc_assert (the_column != INT_MIN);
 119   result->set ("column", new json::integer_number (the_column));
 120   context->m_column_unit = orig_unit;
 121   return result;
 122 }
 123
 124 /* Generate a JSON object for LOC_RANGE.  */
 125
 126 static json::object *
 127 json_from_location_range (diagnostic_context *context,
 128                           const location_range *loc_range, unsigned range_idx)
 129 {
 130   location_t caret_loc = get_pure_location (loc_range->m_loc);
 131
 132   if (caret_loc == UNKNOWN_LOCATION)
 133     return NULL;
 134
 135   location_t start_loc = get_start (loc_range->m_loc);
 136   location_t finish_loc = get_finish (loc_range->m_loc);
 137
 138   json::object *result = new json::object ();
 139   result->set ("caret", json_from_expanded_location (context, caret_loc));
 140   if (start_loc != caret_loc
 141       && start_loc != UNKNOWN_LOCATION)
 142     result->set ("start", json_from_expanded_location (context, start_loc));
 143   if (finish_loc != caret_loc
 144       && finish_loc != UNKNOWN_LOCATION)
 145     result->set ("finish", json_from_expanded_location (context, finish_loc));
 146
 147   if (loc_range->m_label)
 148     {
 149       label_text text (loc_range->m_label->get_text (range_idx));
 150       if (text.get ())
 151         result->set ("label", new json::string (text.get ()));
 152     }
 153
 154   return result;
 155 }
 156
 157 /* Generate a JSON object for HINT.  */
 158
 159 static json::object *
 160 json_from_fixit_hint (diagnostic_context *context, const fixit_hint *hint)
 161 {
 162   json::object *fixit_obj = new json::object ();
 163
 164   location_t start_loc = hint->get_start_loc ();
 165   fixit_obj->set ("start", json_from_expanded_location (context, start_loc));
 166   location_t next_loc = hint->get_next_loc ();
 167   fixit_obj->set ("next", json_from_expanded_location (context, next_loc));
 168   fixit_obj->set ("string", new json::string (hint->get_string ()));
 169
 170   return fixit_obj;
 171 }
 172
 173 /* Generate a JSON object for METADATA.  */
 174
 175 static json::object *
 176 json_from_metadata (const diagnostic_metadata *metadata)
 177 {
 178   json::object *metadata_obj = new json::object ();
 179
 180   if (metadata->get_cwe ())
 181     metadata_obj->set ("cwe",
 182                        new json::integer_number (metadata->get_cwe ()));
 183
 184   return metadata_obj;
 185 }
 186
 187 /* Implementation of "on_end_diagnostic" vfunc for JSON output.
 188    Generate a JSON object for DIAGNOSTIC, and store for output
 189    within current diagnostic group.  */
 190
 191 void
 192 json_output_format::on_end_diagnostic (diagnostic_info *diagnostic,
 193                                        diagnostic_t orig_diag_kind)
 194 {
 195   json::object *diag_obj = new json::object ();
 196
 197   /* Get "kind" of diagnostic.  */
 198   {
 199     static const char *const diagnostic_kind_text[] = {
 200 #define DEFINE_DIAGNOSTIC_KIND(K, T, C) (T),
 201 #include "diagnostic.def"
 202 #undef DEFINE_DIAGNOSTIC_KIND
 203       "must-not-happen"
 204     };
 205     /* Lose the trailing ": ".  */
 206     const char *kind_text = diagnostic_kind_text[diagnostic->kind];
 207     size_t len = strlen (kind_text);
 208     gcc_assert (len > 2);
 209     gcc_assert (kind_text[len - 2] == ':');
 210     gcc_assert (kind_text[len - 1] == ' ');
 211     char *rstrip = xstrdup (kind_text);
 212     rstrip[len - 2] = '\0';
 213     diag_obj->set ("kind", new json::string (rstrip));
 214     free (rstrip);
 215   }
 216
 217   // FIXME: encoding of the message (json::string requires UTF-8)
 218   diag_obj->set ("message",
 219                  new json::string (pp_formatted_text (m_context.printer)));
 220   pp_clear_output_area (m_context.printer);
 221
 222   char *option_text;
 223   option_text = m_context.m_option_name (&m_context, diagnostic->option_index,
 224                                          orig_diag_kind, diagnostic->kind);
 225   if (option_text)
 226     {
 227       diag_obj->set ("option", new json::string (option_text));
 228       free (option_text);
 229     }
 230
 231   if (m_context.m_get_option_url)
 232     {
 233       char *option_url = m_context.m_get_option_url (&m_context,
 234                                                      diagnostic->option_index);
 235       if (option_url)
 236         {
 237           diag_obj->set ("option_url", new json::string (option_url));
 238           free (option_url);
 239         }
 240     }
 241
 242   /* If we've already emitted a diagnostic within this auto_diagnostic_group,
 243      then add diag_obj to its "children" array.  */
 244   if (m_cur_group)
 245     {
 246       gcc_assert (m_cur_children_array);
 247       m_cur_children_array->append (diag_obj);
 248     }
 249   else
 250     {
 251       /* Otherwise, make diag_obj be the top-level object within the group;
 252          add a "children" array and record the column origin.  */
 253       m_toplevel_array->append (diag_obj);
 254       m_cur_group = diag_obj;
 255       m_cur_children_array = new json::array ();
 256       diag_obj->set ("children", m_cur_children_array);
 257       diag_obj->set ("column-origin",
 258                      new json::integer_number (m_context.m_column_origin));
 259     }
 260
 261   const rich_location *richloc = diagnostic->richloc;
 262
 263   json::array *loc_array = new json::array ();
 264   diag_obj->set ("locations", loc_array);
 265
 266   for (unsigned int i = 0; i < richloc->get_num_locations (); i++)
 267     {
 268       const location_range *loc_range = richloc->get_range (i);
 269       json::object *loc_obj
 270         = json_from_location_range (&m_context, loc_range, i);
 271       if (loc_obj)
 272         loc_array->append (loc_obj);
 273     }
 274
 275   if (richloc->get_num_fixit_hints ())
 276     {
 277       json::array *fixit_array = new json::array ();
 278       diag_obj->set ("fixits", fixit_array);
 279       for (unsigned int i = 0; i < richloc->get_num_fixit_hints (); i++)
 280         {
 281           const fixit_hint *hint = richloc->get_fixit_hint (i);
 282           json::object *fixit_obj = json_from_fixit_hint (&m_context, hint);
 283           fixit_array->append (fixit_obj);
 284         }
 285     }
 286
 287   /* TODO: tree-ish things:
 288      TODO: functions
 289      TODO: inlining information
 290      TODO: macro expansion information.  */
 291
 292   if (diagnostic->metadata)
 293     {
 294       json::object *metadata_obj = json_from_metadata (diagnostic->metadata);
 295       diag_obj->set ("metadata", metadata_obj);
 296     }
 297
 298   const diagnostic_path *path = richloc->get_path ();
 299   if (path && m_context.m_make_json_for_path)
 300     {
 301       json::value *path_value
 302         = m_context.m_make_json_for_path (&m_context, path);
 303       diag_obj->set ("path", path_value);
 304     }
 305
 306   diag_obj->set ("escape-source",
 307                  new json::literal (richloc->escape_on_output_p ()));
 308 }
 309
 310 class json_stderr_output_format : public json_output_format
 311 {
 312 public:
 313   json_stderr_output_format (diagnostic_context &context)
 314   : json_output_format (context)
 315   {
 316   }
 317   ~json_stderr_output_format ()
 318   {
 319     flush_to_file (stderr);
 320   }
 321 };
 322
 323 class json_file_output_format : public json_output_format
 324 {
 325 public:
 326   json_file_output_format (diagnostic_context &context,
 327                            const char *base_file_name)
 328   : json_output_format (context),
 329     m_base_file_name (xstrdup (base_file_name))
 330   {
 331   }
 332
 333   ~json_file_output_format ()
 334   {
 335     char *filename = concat (m_base_file_name, ".gcc.json", NULL);
 336     free (m_base_file_name);
 337     m_base_file_name = nullptr;
 338     FILE *outf = fopen (filename, "w");
 339     if (!outf)
 340       {
 341         const char *errstr = xstrerror (errno);
 342         fnotice (stderr, "error: unable to open '%s' for writing: %s\n",
 343                  filename, errstr);
 344         free (filename);
 345         return;
 346       }
 347     flush_to_file (outf);
 348     fclose (outf);
 349     free (filename);
 350   }
 351
 352 private:
 353   char *m_base_file_name;
 354 };
 355
 356 /* Populate CONTEXT in preparation for JSON output (either to stderr, or
 357    to a file).  */
 358
 359 static void
 360 diagnostic_output_format_init_json (diagnostic_context *context)
 361 {
 362   /* Override callbacks.  */
 363   context->m_print_path = nullptr; /* handled in json_end_diagnostic.  */
 364
 365   /* The metadata is handled in JSON format, rather than as text.  */
 366   context->set_show_cwe (false);
 367   context->set_show_rules (false);
 368
 369   /* The option is handled in JSON format, rather than as text.  */
 370   context->set_show_option_requested (false);
 371
 372   /* Don't colorize the text.  */
 373   pp_show_color (context->printer) = false;
 374 }
 375
 376 /* Populate CONTEXT in preparation for JSON output to stderr.  */
 377
 378 void
 379 diagnostic_output_format_init_json_stderr (diagnostic_context *context)
 380 {
 381   diagnostic_output_format_init_json (context);
 382   context->set_output_format (new json_stderr_output_format (*context));
 383 }
 384
 385 /* Populate CONTEXT in preparation for JSON output to a file named
 386    BASE_FILE_NAME.gcc.json.  */
 387
 388 void
 389 diagnostic_output_format_init_json_file (diagnostic_context *context,
 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                                                            base_file_name));
 395 }
 396
 397 #if CHECKING_P
 398
 399 namespace selftest {
 400
 401 /* We shouldn't call json_from_expanded_location on UNKNOWN_LOCATION,
 402    but verify that we handle this gracefully.  */
 403
 404 static void
 405 test_unknown_location ()
 406 {
 407   test_diagnostic_context dc;
 408   delete json_from_expanded_location (&dc, UNKNOWN_LOCATION);
 409 }
 410
 411 /* Verify that we gracefully handle attempts to serialize bad
 412    compound locations.  */
 413
 414 static void
 415 test_bad_endpoints ()
 416 {
 417   location_t bad_endpoints
 418     = make_location (BUILTINS_LOCATION,
 419                      UNKNOWN_LOCATION, UNKNOWN_LOCATION);
 420
 421   location_range loc_range;
 422   loc_range.m_loc = bad_endpoints;
 423   loc_range.m_range_display_kind = SHOW_RANGE_WITH_CARET;
 424   loc_range.m_label = NULL;
 425
 426   test_diagnostic_context dc;
 427   json::object *obj = json_from_location_range (&dc, &loc_range, 0);
 428   /* We should have a "caret" value, but no "start" or "finish" values.  */
 429   ASSERT_TRUE (obj != NULL);
 430   ASSERT_TRUE (obj->get ("caret") != NULL);
 431   ASSERT_TRUE (obj->get ("start") == NULL);
 432   ASSERT_TRUE (obj->get ("finish") == NULL);
 433   delete obj;
 434 }
 435
 436 /* Run all of the selftests within this file.  */
 437
 438 void
 439 diagnostic_format_json_cc_tests ()
 440 {
 441   test_unknown_location ();
 442   test_bad_endpoints ();
 443 }
 444
 445 } // namespace selftest
 446
 447 #endif /* #if CHECKING_P */