lib/plugin/plugin.c

   1 /*
   2  * plugin.c
   3  *
   4  * Babeltrace Plugin (generic)
   5  *
   6  * Copyright 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   7  * Copyright 2017 Philippe Proulx <pproulx@efficios.com>
   8  *
   9  * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  22  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  24  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  25  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  26  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  27  * SOFTWARE.
  28  */
  29
  30 #define BT_LOG_TAG "PLUGIN"
  31 #include <babeltrace/lib-logging-internal.h>
  32
  33 #include <babeltrace/babeltrace-internal.h>
  34 #include <babeltrace/compiler-internal.h>
  35 #include <babeltrace/ref.h>
  36 #include <babeltrace/common-internal.h>
  37 #include <babeltrace/plugin/plugin-internal.h>
  38 #include <babeltrace/plugin/plugin-so-internal.h>
  39 #include <babeltrace/graph/component-class.h>
  40 #include <babeltrace/graph/component-class-internal.h>
  41 #include <babeltrace/types.h>
  42 #include <glib.h>
  43 #include <unistd.h>
  44 #include <stdlib.h>
  45 #include <stdint.h>
  46 #include <inttypes.h>
  47 #include <sys/stat.h>
  48 #include <ftw.h>
  49 #include <pthread.h>
  50
  51 #define PYTHON_PLUGIN_PROVIDER_FILENAME "libbabeltrace-python-plugin-provider." G_MODULE_SUFFIX
  52 #define PYTHON_PLUGIN_PROVIDER_SYM_NAME bt_plugin_python_create_all_from_file
  53 #define PYTHON_PLUGIN_PROVIDER_SYM_NAME_STR     TOSTRING(PYTHON_PLUGIN_PROVIDER_SYM_NAME)
  54
  55 #define APPEND_ALL_FROM_DIR_NFDOPEN_MAX 8
  56
  57 #ifdef BT_BUILT_IN_PYTHON_PLUGIN_SUPPORT
  58 #include <babeltrace/plugin/python-plugin-provider-internal.h>
  59
  60 static
  61 struct bt_plugin_set *(*bt_plugin_python_create_all_from_file_sym)(const char *path) =
  62         bt_plugin_python_create_all_from_file;
  63 #else /* BT_BUILT_IN_PYTHON_PLUGIN_SUPPORT */
  64 static GModule *python_plugin_provider_module;
  65 static
  66 struct bt_plugin_set *(*bt_plugin_python_create_all_from_file_sym)(const char *path);
  67
  68 __attribute__((constructor)) static
  69 void init_python_plugin_provider(void) {
  70         BT_LOGD_STR("Loading Python plugin provider module.");
  71         python_plugin_provider_module =
  72                 g_module_open(PYTHON_PLUGIN_PROVIDER_FILENAME, 0);
  73         if (!python_plugin_provider_module) {
  74                 BT_LOGI("Cannot open `%s`: %s: continuing without Python plugin support.",
  75                         PYTHON_PLUGIN_PROVIDER_FILENAME, g_module_error());
  76                 return;
  77         }
  78
  79         if (!g_module_symbol(python_plugin_provider_module,
  80                         PYTHON_PLUGIN_PROVIDER_SYM_NAME_STR,
  81                         (gpointer) &bt_plugin_python_create_all_from_file_sym)) {
  82                 BT_LOGI("Cannot find the Python plugin provider loading symbol: continuing without Python plugin support: "
  83                         "file=\"%s\", symbol=\"%s\"",
  84                         PYTHON_PLUGIN_PROVIDER_FILENAME,
  85                         PYTHON_PLUGIN_PROVIDER_SYM_NAME_STR);
  86                 return;
  87         }
  88
  89         BT_LOGI("Loaded Python plugin provider module: addr=%p",
  90                 python_plugin_provider_module);
  91 }
  92
  93 __attribute__((destructor)) static
  94 void fini_python_plugin_provider(void) {
  95         if (python_plugin_provider_module) {
  96                 BT_LOGD("Unloading Python plugin provider module.");
  97
  98                 if (!g_module_close(python_plugin_provider_module)) {
  99                         BT_LOGE("Failed to close the Python plugin provider module: %s.",
 100                                 g_module_error());
 101                 }
 102
 103                 python_plugin_provider_module = NULL;
 104         }
 105 }
 106 #endif
 107
 108 extern
 109 int64_t bt_plugin_set_get_plugin_count(struct bt_plugin_set *plugin_set)
 110 {
 111         int64_t count = -1;
 112
 113         if (!plugin_set) {
 114                 BT_LOGW_STR("Invalid parameter: plugin set is NULL.");
 115                 goto end;
 116         }
 117
 118         count = (int64_t) plugin_set->plugins->len;
 119
 120 end:
 121         return count;
 122 }
 123
 124 extern
 125 struct bt_plugin *bt_plugin_set_get_plugin(struct bt_plugin_set *plugin_set,
 126                 uint64_t index)
 127 {
 128         struct bt_plugin *plugin = NULL;
 129
 130         if (!plugin_set) {
 131                 BT_LOGW_STR("Invalid parameter: plugin set is NULL.");
 132                 goto end;
 133         }
 134
 135         if (index >= plugin_set->plugins->len) {
 136                 BT_LOGW("Invalid parameter: index is out of bounds: "
 137                         "addr=%p, index=%" PRIu64 ", count=%u",
 138                         plugin_set, index, plugin_set->plugins->len);
 139                 goto end;
 140         }
 141
 142         plugin = bt_get(g_ptr_array_index(plugin_set->plugins, index));
 143
 144 end:
 145         return plugin;
 146 }
 147
 148 struct bt_plugin_set *bt_plugin_create_all_from_static(void)
 149 {
 150         /* bt_plugin_so_create_all_from_static() logs errors */
 151         return bt_plugin_so_create_all_from_static();
 152 }
 153
 154 struct bt_plugin_set *bt_plugin_create_all_from_file(const char *path)
 155 {
 156         struct bt_plugin_set *plugin_set = NULL;
 157
 158         if (!path) {
 159                 BT_LOGW_STR("Invalid parameter: path is NULL.");
 160                 goto end;
 161         }
 162
 163         BT_LOGD("Creating plugins from file: path=\"%s\"", path);
 164
 165         /* Try shared object plugins */
 166         plugin_set = bt_plugin_so_create_all_from_file(path);
 167         if (plugin_set) {
 168                 goto end;
 169         }
 170
 171         /* Try Python plugins if support is available */
 172         if (bt_plugin_python_create_all_from_file_sym) {
 173                 plugin_set = bt_plugin_python_create_all_from_file_sym(path);
 174                 if (plugin_set) {
 175                         goto end;
 176                 }
 177         }
 178
 179 end:
 180         if (plugin_set) {
 181                 BT_LOGD("Created %u plugins from file: "
 182                         "path=\"%s\", count=%u, plugin-set-addr=%p",
 183                         plugin_set->plugins->len, path,
 184                         plugin_set->plugins->len, plugin_set);
 185         } else {
 186                 BT_LOGD("Found no plugins in file: path=\"%s\"", path);
 187         }
 188
 189         return plugin_set;
 190 }
 191
 192 static void destroy_gstring(void *data)
 193 {
 194         g_string_free(data, TRUE);
 195 }
 196
 197 struct bt_plugin *bt_plugin_find(const char *plugin_name)
 198 {
 199         const char *system_plugin_dir;
 200         char *home_plugin_dir = NULL;
 201         const char *envvar;
 202         struct bt_plugin *plugin = NULL;
 203         struct bt_plugin_set *plugin_set = NULL;
 204         GPtrArray *dirs = NULL;
 205         int ret;
 206         size_t i, j;
 207
 208         if (!plugin_name) {
 209                 BT_LOGW_STR("Invalid parameter: plugin name is NULL.");
 210                 goto end;
 211         }
 212
 213         BT_LOGD("Finding named plugin in standard directories and built-in plugins: "
 214                 "name=\"%s\"", plugin_name);
 215         dirs = g_ptr_array_new_with_free_func((GDestroyNotify) destroy_gstring);
 216         if (!dirs) {
 217                 BT_LOGE_STR("Failed to allocate a GPtrArray.");
 218                 goto end;
 219         }
 220
 221         /*
 222          * Search order is:
 223          *
 224          * 1. BABELTRACE_PLUGIN_PATH environment variable
 225          *    (colon-separated list of directories)
 226          * 2. ~/.local/lib/babeltrace/plugins
 227          * 3. Default system directory for Babeltrace plugins, usually
 228          *    /usr/lib/babeltrace/plugins or
 229          *    /usr/local/lib/babeltrace/plugins if installed
 230          *    locally
 231          * 4. Built-in plugins (static)
 232          *
 233          * Directories are searched non-recursively.
 234          */
 235         envvar = getenv("BABELTRACE_PLUGIN_PATH");
 236         if (envvar) {
 237                 ret = bt_common_append_plugin_path_dirs(envvar, dirs);
 238                 if (ret) {
 239                         BT_LOGE_STR("Failed to append plugin path to array of directories.");
 240                         goto end;
 241                 }
 242         }
 243
 244         home_plugin_dir = bt_common_get_home_plugin_path();
 245         if (home_plugin_dir) {
 246                 GString *home_plugin_dir_str =
 247                         g_string_new(home_plugin_dir);
 248
 249                 if (!home_plugin_dir_str) {
 250                         BT_LOGE_STR("Failed to allocate a GString.");
 251                         goto end;
 252                 }
 253
 254                 g_ptr_array_add(dirs, home_plugin_dir_str);
 255         }
 256
 257         system_plugin_dir = bt_common_get_system_plugin_path();
 258         if (system_plugin_dir) {
 259                 GString *system_plugin_dir_str =
 260                         g_string_new(system_plugin_dir);
 261
 262                 if (!system_plugin_dir_str) {
 263                         BT_LOGE_STR("Failed to allocate a GString.");
 264                         goto end;
 265                 }
 266
 267                 g_ptr_array_add(dirs, system_plugin_dir_str);
 268         }
 269
 270         for (i = 0; i < dirs->len; i++) {
 271                 GString *dir = g_ptr_array_index(dirs, i);
 272
 273                 BT_PUT(plugin_set);
 274
 275                 /*
 276                  * Skip this if the directory does not exist because
 277                  * bt_plugin_create_all_from_dir() would log a warning.
 278                  */
 279                 if (!g_file_test(dir->str, G_FILE_TEST_IS_DIR)) {
 280                         BT_LOGV("Skipping nonexistent directory path: "
 281                                 "path=\"%s\"", dir->str);
 282                         continue;
 283                 }
 284
 285                 /* bt_plugin_create_all_from_dir() logs details/errors */
 286                 plugin_set = bt_plugin_create_all_from_dir(dir->str, BT_FALSE);
 287                 if (!plugin_set) {
 288                         BT_LOGD("No plugins found in directory: path=\"%s\"",
 289                                 dir->str);
 290                         continue;
 291                 }
 292
 293                 for (j = 0; j < plugin_set->plugins->len; j++) {
 294                         struct bt_plugin *candidate_plugin =
 295                                 g_ptr_array_index(plugin_set->plugins, j);
 296
 297                         if (strcmp(bt_plugin_get_name(candidate_plugin),
 298                                         plugin_name) == 0) {
 299                                 BT_LOGD("Plugin found in directory: name=\"%s\", path=\"%s\"",
 300                                         plugin_name, dir->str);
 301                                 plugin = bt_get(candidate_plugin);
 302                                 goto end;
 303                         }
 304                 }
 305
 306                 BT_LOGD("Plugin not found in directory: name=\"%s\", path=\"%s\"",
 307                         plugin_name, dir->str);
 308         }
 309
 310         bt_put(plugin_set);
 311         plugin_set = bt_plugin_create_all_from_static();
 312         if (plugin_set) {
 313                 for (j = 0; j < plugin_set->plugins->len; j++) {
 314                         struct bt_plugin *candidate_plugin =
 315                                 g_ptr_array_index(plugin_set->plugins, j);
 316
 317                         if (strcmp(bt_plugin_get_name(candidate_plugin),
 318                                         plugin_name) == 0) {
 319                                 BT_LOGD("Plugin found in built-in plugins: "
 320                                         "name=\"%s\"", plugin_name);
 321                                 plugin = bt_get(candidate_plugin);
 322                                 goto end;
 323                         }
 324                 }
 325         }
 326
 327 end:
 328         free(home_plugin_dir);
 329         bt_put(plugin_set);
 330
 331         if (dirs) {
 332                 g_ptr_array_free(dirs, TRUE);
 333         }
 334
 335         if (plugin) {
 336                 BT_LOGD("Found plugin in standard directories and built-in plugins: "
 337                         "addr=%p, name=\"%s\", path=\"%s\"",
 338                         plugin, plugin_name, bt_plugin_get_path(plugin));
 339         } else {
 340                 BT_LOGD("No plugin found in standard directories and built-in plugins: "
 341                         "name=\"%s\"", plugin_name);
 342         }
 343
 344         return plugin;
 345 }
 346
 347 struct bt_component_class *bt_plugin_find_component_class(
 348                 const char *plugin_name, const char *comp_cls_name,
 349                 enum bt_component_class_type comp_cls_type)
 350 {
 351         struct bt_plugin *plugin = NULL;
 352         struct bt_component_class *comp_cls = NULL;
 353
 354         if (!plugin_name) {
 355                 BT_LOGW_STR("Invalid parameter: plugin name is NULL.");
 356                 goto end;
 357         }
 358
 359         if (!comp_cls_name) {
 360                 BT_LOGW_STR("Invalid parameter: component class name is NULL.");
 361                 goto end;
 362         }
 363
 364         BT_LOGD("Finding named plugin and component class in standard directories and built-in plugins: "
 365                 "plugin-name=\"%s\", comp-class-name=\"%s\"",
 366                 plugin_name, comp_cls_name);
 367         plugin = bt_plugin_find(plugin_name);
 368         if (!plugin) {
 369                 BT_LOGD_STR("Plugin not found.");
 370                 goto end;
 371         }
 372
 373         comp_cls = bt_plugin_get_component_class_by_name_and_type(
 374                 plugin, comp_cls_name, comp_cls_type);
 375         if (!comp_cls) {
 376                 BT_LOGD("Component class not found in plugin: "
 377                         "plugin-addr=%p, plugin-path=\"%s\"",
 378                         plugin, bt_plugin_get_path(plugin));
 379         }
 380
 381 end:
 382         bt_put(plugin);
 383         return comp_cls;
 384 }
 385
 386 static struct {
 387         pthread_mutex_t lock;
 388         struct bt_plugin_set *plugin_set;
 389         bt_bool recurse;
 390 } append_all_from_dir_info = {
 391         .lock = PTHREAD_MUTEX_INITIALIZER
 392 };
 393
 394 static
 395 int nftw_append_all_from_dir(const char *file, const struct stat *sb, int flag,
 396                 struct FTW *s)
 397 {
 398         int ret = 0;
 399         const char *name = file + s->base;
 400
 401         /* Check for recursion */
 402         if (!append_all_from_dir_info.recurse && s->level > 1) {
 403                 goto end;
 404         }
 405
 406         switch (flag) {
 407         case FTW_F:
 408         {
 409                 struct bt_plugin_set *plugins_from_file;
 410
 411                 if (name[0] == '.') {
 412                         /* Skip hidden files */
 413                         BT_LOGV("Skipping hidden file: path=\"%s\"", file);
 414                         goto end;
 415                 }
 416
 417                 plugins_from_file = bt_plugin_create_all_from_file(file);
 418
 419                 if (plugins_from_file) {
 420                         size_t j;
 421
 422                         for (j = 0; j < plugins_from_file->plugins->len; j++) {
 423                                 struct bt_plugin *plugin =
 424                                         g_ptr_array_index(plugins_from_file->plugins, j);
 425
 426                                 BT_LOGD("Adding plugin to plugin set: "
 427                                         "plugin-path=\"%s\", plugin-addr=%p, plugin-name=\"%s\"",
 428                                         file, plugin, bt_plugin_get_name(plugin));
 429                                 bt_plugin_set_add_plugin(append_all_from_dir_info.plugin_set, plugin);
 430                         }
 431
 432                         bt_put(plugins_from_file);
 433                 }
 434                 break;
 435         }
 436         case FTW_DNR:
 437                 /* Continue to next file / directory. */
 438                 BT_LOGW("Cannot enter directory: continuing: path=\"%s\"", file);
 439                 break;
 440         case FTW_NS:
 441                 /* Continue to next file / directory. */
 442                 BT_LOGD("Cannot get file information: continuing: path=\"%s\"", file);
 443                 break;
 444         }
 445
 446 end:
 447         return ret;
 448 }
 449
 450 static
 451 enum bt_plugin_status bt_plugin_create_append_all_from_dir(
 452                 struct bt_plugin_set *plugin_set, const char *path,
 453                 bt_bool recurse)
 454 {
 455         int nftw_flags = FTW_PHYS;
 456         size_t path_len;
 457         enum bt_plugin_status ret = BT_PLUGIN_STATUS_OK;
 458
 459         if (!path) {
 460                 BT_LOGW_STR("Invalid parameter: path is NULL.");
 461                 ret = BT_PLUGIN_STATUS_ERROR;
 462                 goto end;
 463         }
 464
 465         path_len = strlen(path);
 466         if (path_len >= PATH_MAX) {
 467                 BT_LOGW("Invalid parameter: path length is too large: "
 468                         "path-length=%zu", path_len);
 469                 ret = BT_PLUGIN_STATUS_ERROR;
 470                 goto end;
 471         }
 472
 473         pthread_mutex_lock(&append_all_from_dir_info.lock);
 474
 475         append_all_from_dir_info.plugin_set = plugin_set;
 476         append_all_from_dir_info.recurse = recurse;
 477         ret = nftw(path, nftw_append_all_from_dir,
 478                 APPEND_ALL_FROM_DIR_NFDOPEN_MAX, nftw_flags);
 479
 480         pthread_mutex_unlock(&append_all_from_dir_info.lock);
 481
 482         if (ret != 0) {
 483                 BT_LOGW("Cannot open directory: %s: path=\"%s\", errno=%d",
 484                         strerror(errno), path, errno);
 485                 ret = BT_PLUGIN_STATUS_ERROR;
 486         }
 487
 488 end:
 489         return ret;
 490 }
 491
 492 struct bt_plugin_set *bt_plugin_create_all_from_dir(const char *path,
 493                 bt_bool recurse)
 494 {
 495         struct bt_plugin_set *plugin_set;
 496         enum bt_plugin_status status;
 497
 498         BT_LOGD("Creating all plugins in directory: path=\"%s\", recurse=%d",
 499                 path, recurse);
 500         plugin_set = bt_plugin_set_create();
 501         if (!plugin_set) {
 502                 BT_LOGE_STR("Cannot create empty plugin set.");
 503                 goto error;
 504         }
 505
 506         /* Append found plugins to array */
 507         status = bt_plugin_create_append_all_from_dir(plugin_set, path,
 508                 recurse);
 509         if (status < 0) {
 510                 BT_LOGW("Cannot append plugins found in directory: "
 511                         "path=\"%s\", status=%s",
 512                         path, bt_plugin_status_string(status));
 513                 goto error;
 514         }
 515
 516         BT_LOGD("Created %u plugins from directory: count=%u, path=\"%s\"",
 517                 plugin_set->plugins->len, plugin_set->plugins->len, path);
 518         goto end;
 519
 520 error:
 521         BT_PUT(plugin_set);
 522
 523 end:
 524         return plugin_set;
 525 }
 526
 527 const char *bt_plugin_get_name(struct bt_plugin *plugin)
 528 {
 529         const char *val = NULL;
 530
 531         if (!plugin) {
 532                 BT_LOGW_STR("Invalid parameter: plugin is NULL.");
 533                 goto end;
 534         }
 535
 536         if (plugin->info.name_set) {
 537                 val = plugin->info.name->str;
 538         }
 539
 540 end:
 541         return val;
 542 }
 543
 544 const char *bt_plugin_get_author(struct bt_plugin *plugin)
 545 {
 546         const char *val = NULL;
 547
 548         if (!plugin) {
 549                 BT_LOGW_STR("Invalid parameter: plugin is NULL.");
 550                 goto end;
 551         }
 552
 553         if (plugin->info.author_set) {
 554                 val = plugin->info.author->str;
 555         }
 556
 557 end:
 558         return val;
 559 }
 560
 561 const char *bt_plugin_get_license(struct bt_plugin *plugin)
 562 {
 563         const char *val = NULL;
 564
 565         if (!plugin) {
 566                 BT_LOGW_STR("Invalid parameter: plugin is NULL.");
 567                 goto end;
 568         }
 569
 570         if (plugin->info.license_set) {
 571                 val = plugin->info.license->str;
 572         }
 573
 574 end:
 575         return val;
 576 }
 577
 578 const char *bt_plugin_get_path(struct bt_plugin *plugin)
 579 {
 580         const char *val = NULL;
 581
 582         if (!plugin) {
 583                 BT_LOGW_STR("Invalid parameter: plugin is NULL.");
 584                 goto end;
 585         }
 586
 587         if (plugin->info.path_set) {
 588                 val = plugin->info.path->str;
 589         }
 590
 591 end:
 592         return val;
 593 }
 594
 595 const char *bt_plugin_get_description(struct bt_plugin *plugin)
 596 {
 597         const char *val = NULL;
 598
 599         if (!plugin) {
 600                 BT_LOGW_STR("Invalid parameter: plugin is NULL.");
 601                 goto end;
 602         }
 603
 604         if (plugin->info.description_set) {
 605                 val = plugin->info.description->str;
 606         }
 607
 608 end:
 609         return val;
 610 }
 611
 612 enum bt_plugin_status bt_plugin_get_version(struct bt_plugin *plugin,
 613                 unsigned int *major, unsigned int *minor, unsigned int *patch,
 614                 const char **extra)
 615 {
 616         enum bt_plugin_status status = BT_PLUGIN_STATUS_OK;
 617
 618         if (!plugin) {
 619                 BT_LOGW_STR("Invalid parameter: plugin is NULL.");
 620                 status = BT_PLUGIN_STATUS_ERROR;
 621                 goto end;
 622         }
 623
 624         if (!plugin->info.version_set) {
 625                 BT_LOGV("Plugin's version is not set: addr=%p", plugin);
 626                 status = BT_PLUGIN_STATUS_ERROR;
 627                 goto end;
 628         }
 629
 630         if (major) {
 631                 *major = plugin->info.version.major;
 632         }
 633
 634         if (minor) {
 635                 *minor = plugin->info.version.minor;
 636         }
 637
 638         if (patch) {
 639                 *patch = plugin->info.version.patch;
 640         }
 641
 642         if (extra) {
 643                 *extra = plugin->info.version.extra->str;
 644         }
 645
 646 end:
 647         return status;
 648 }
 649
 650 int64_t bt_plugin_get_component_class_count(struct bt_plugin *plugin)
 651 {
 652         return plugin ? plugin->comp_classes->len : (int64_t) -1;
 653 }
 654
 655 struct bt_component_class *bt_plugin_get_component_class_by_index(
 656                 struct bt_plugin *plugin, uint64_t index)
 657 {
 658         struct bt_component_class *comp_class = NULL;
 659
 660         if (!plugin) {
 661                 BT_LOGW_STR("Invalid parameter: plugin is NULL.");
 662                 goto error;
 663         }
 664
 665         if (index >= plugin->comp_classes->len) {
 666                 BT_LOGW("Invalid parameter: index is out of bounds: "
 667                         "addr=%p, index=%" PRIu64 ", count=%u",
 668                         plugin, index, plugin->comp_classes->len);
 669                 goto error;
 670         }
 671
 672         comp_class = g_ptr_array_index(plugin->comp_classes, index);
 673         bt_get(comp_class);
 674         goto end;
 675
 676 error:
 677         BT_PUT(comp_class);
 678
 679 end:
 680         return comp_class;
 681 }
 682
 683 struct bt_component_class *bt_plugin_get_component_class_by_name_and_type(
 684                 struct bt_plugin *plugin, const char *name,
 685                 enum bt_component_class_type type)
 686 {
 687         struct bt_component_class *comp_class = NULL;
 688         size_t i;
 689
 690         if (!plugin) {
 691                 BT_LOGW_STR("Invalid parameter: plugin is NULL.");
 692                 goto error;
 693         }
 694
 695         if (!name) {
 696                 BT_LOGW_STR("Invalid parameter: name is NULL.");
 697                 goto error;
 698         }
 699
 700         for (i = 0; i < plugin->comp_classes->len; i++) {
 701                 struct bt_component_class *comp_class_candidate =
 702                         g_ptr_array_index(plugin->comp_classes, i);
 703                 const char *comp_class_cand_name =
 704                         bt_component_class_get_name(comp_class_candidate);
 705                 enum bt_component_class_type comp_class_cand_type =
 706                         bt_component_class_get_type(comp_class_candidate);
 707
 708                 assert(comp_class_cand_name);
 709                 assert(comp_class_cand_type >= 0);
 710
 711                 if (strcmp(name, comp_class_cand_name) == 0 &&
 712                                 comp_class_cand_type == type) {
 713                         comp_class = bt_get(comp_class_candidate);
 714                         break;
 715                 }
 716         }
 717
 718         goto end;
 719
 720 error:
 721         BT_PUT(comp_class);
 722
 723 end:
 724         return comp_class;
 725 }
 726
 727 enum bt_plugin_status bt_plugin_add_component_class(
 728         struct bt_plugin *plugin, struct bt_component_class *comp_class)
 729 {
 730         enum bt_plugin_status status = BT_PLUGIN_STATUS_OK;
 731         struct bt_component_class *comp_class_dup = NULL;
 732         int comp_class_index = -1;
 733
 734         if (!plugin) {
 735                 BT_LOGW_STR("Invalid parameter: plugin is NULL.");
 736                 goto error;
 737         }
 738
 739         if (!comp_class) {
 740                 BT_LOGW_STR("Invalid parameter: component class is NULL.");
 741                 goto error;
 742         }
 743
 744         if (plugin->frozen) {
 745                 BT_LOGW("Invalid parameter: plugin is frozen: "
 746                         "addr=%p, name=\"%s\"", plugin,
 747                         bt_plugin_get_name(plugin));
 748                 goto error;
 749         }
 750
 751         /* Check for duplicate */
 752         comp_class_dup = bt_plugin_get_component_class_by_name_and_type(plugin,
 753                 bt_component_class_get_name(comp_class),
 754                 bt_component_class_get_type(comp_class));
 755         if (comp_class_dup) {
 756                 BT_LOGW("Invalid parameter: a component class with this name and type already exists in the plugin: "
 757                         "plugin-addr=%p, plugin-name=\"%s\", plugin-path=\"%s\", "
 758                         "comp-class-name=\"%s\", comp-class-type=%s",
 759                         plugin, bt_plugin_get_name(plugin),
 760                         bt_plugin_get_path(plugin),
 761                         bt_component_class_get_name(comp_class),
 762                         bt_component_class_type_string(
 763                                 bt_component_class_get_type(comp_class)));
 764                 goto error;
 765         }
 766
 767         /* Add new component class */
 768         comp_class_index = plugin->comp_classes->len;
 769         g_ptr_array_add(plugin->comp_classes, bt_get(comp_class));
 770
 771         /* Special case for a shared object plugin */
 772         if (plugin->type == BT_PLUGIN_TYPE_SO) {
 773                 bt_plugin_so_on_add_component_class(plugin, comp_class);
 774         }
 775
 776         BT_LOGD("Added component class to plugin: "
 777                 "plugin-addr=%p, plugin-name=\"%s\", plugin-path=\"%s\", "
 778                 "comp-class-addr=%p, comp-class-name=\"%s\", comp-class-type=%s",
 779                 plugin, bt_plugin_get_name(plugin),
 780                 bt_plugin_get_path(plugin),
 781                 comp_class,
 782                 bt_component_class_get_name(comp_class),
 783                 bt_component_class_type_string(
 784                         bt_component_class_get_type(comp_class)));
 785         goto end;
 786
 787 error:
 788         /* Remove entry from plugin's component classes (if added) */
 789         if (comp_class_index >= 0) {
 790                 g_ptr_array_remove_index(plugin->comp_classes,
 791                         comp_class_index);
 792         }
 793
 794         status = BT_PLUGIN_STATUS_ERROR;
 795
 796 end:
 797         bt_put(comp_class_dup);
 798         return status;
 799 }