src/lib/plugin/plugin.c

   1 /*
   2  * Copyright 2017-2018 Philippe Proulx <pproulx@efficios.com>
   3  * Copyright 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   4  *
   5  * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23  * SOFTWARE.
  24  */
  25
  26 #define BT_LOG_TAG "LIB/PLUGIN"
  27 #include "lib/logging.h"
  28
  29 #include "common/assert.h"
  30 #include "lib/assert-pre.h"
  31 #include "common/macros.h"
  32 #include "compat/compiler.h"
  33 #include "common/common.h"
  34 #include <babeltrace2/plugin/plugin-const.h>
  35 #include <babeltrace2/graph/component-class-const.h>
  36 #include <babeltrace2/current-thread.h>
  37 #include "lib/graph/component-class.h"
  38 #include <babeltrace2/types.h>
  39 #include <glib.h>
  40 #include <unistd.h>
  41 #include <stdlib.h>
  42 #include <stdint.h>
  43 #include <inttypes.h>
  44 #include <sys/stat.h>
  45 #include <ftw.h>
  46 #include <pthread.h>
  47
  48 #include "plugin.h"
  49 #include "plugin-so.h"
  50 #include "lib/func-status.h"
  51
  52 #define PYTHON_PLUGIN_PROVIDER_FILENAME "libbabeltrace2-python-plugin-provider." G_MODULE_SUFFIX
  53 #define PYTHON_PLUGIN_PROVIDER_SYM_NAME bt_plugin_python_create_all_from_file
  54 #define PYTHON_PLUGIN_PROVIDER_SYM_NAME_STR     G_STRINGIFY(PYTHON_PLUGIN_PROVIDER_SYM_NAME)
  55
  56 #define APPEND_ALL_FROM_DIR_NFDOPEN_MAX 8
  57
  58 #ifdef BT_BUILT_IN_PYTHON_PLUGIN_SUPPORT
  59 #include <plugin/python-plugin-provider.h>
  60
  61 static
  62 int (*bt_plugin_python_create_all_from_file_sym)(
  63                 const char *path, bool fail_on_load_error,
  64                 struct bt_plugin_set **plugin_set_out) =
  65         bt_plugin_python_create_all_from_file;
  66
  67 static
  68 enum bt_plugin_status init_python_plugin_provider(void)
  69 {
  70 }
  71 #else /* BT_BUILT_IN_PYTHON_PLUGIN_SUPPORT */
  72 static GModule *python_plugin_provider_module;
  73
  74 static
  75 int (*bt_plugin_python_create_all_from_file_sym)(
  76                 const char *path, bool fail_on_load_error,
  77                  struct bt_plugin_set **plugin_set_out);
  78
  79 static
  80 int init_python_plugin_provider(void) {
  81         int status = BT_FUNC_STATUS_OK;
  82
  83         if (bt_plugin_python_create_all_from_file_sym != NULL) {
  84                 goto end;
  85         }
  86
  87         BT_LOGI_STR("Loading Python plugin provider module.");
  88         python_plugin_provider_module =
  89                 g_module_open(PYTHON_PLUGIN_PROVIDER_FILENAME, 0);
  90         if (!python_plugin_provider_module) {
  91                 /*
  92                  * This is not an error. The whole point of having an
  93                  * external Python plugin provider is that it can be
  94                  * missing and the Babeltrace library still works.
  95                  */
  96                 BT_LOGI("Cannot open `%s`: %s: continuing without Python plugin support.",
  97                         PYTHON_PLUGIN_PROVIDER_FILENAME, g_module_error());
  98                 goto end;
  99         }
 100
 101         if (!g_module_symbol(python_plugin_provider_module,
 102                         PYTHON_PLUGIN_PROVIDER_SYM_NAME_STR,
 103                         (gpointer) &bt_plugin_python_create_all_from_file_sym)) {
 104                 /*
 105                  * This is an error because, since we found the Python
 106                  * plugin provider shared object, we expect this symbol
 107                  * to exist.
 108                  */
 109                 BT_LIB_LOGE_APPEND_CAUSE(
 110                         "Cannot find the Python plugin provider loading symbol: "
 111                         "%s: continuing without Python plugin support: "
 112                         "file=\"%s\", symbol=\"%s\"",
 113                         g_module_error(),
 114                         PYTHON_PLUGIN_PROVIDER_FILENAME,
 115                         PYTHON_PLUGIN_PROVIDER_SYM_NAME_STR);
 116                 status = BT_FUNC_STATUS_ERROR;
 117                 goto end;
 118         }
 119
 120         BT_LOGI("Loaded Python plugin provider module: addr=%p",
 121                 python_plugin_provider_module);
 122
 123 end:
 124         return status;
 125 }
 126
 127 __attribute__((destructor)) static
 128 void fini_python_plugin_provider(void) {
 129         if (python_plugin_provider_module) {
 130                 BT_LOGI("Unloading Python plugin provider module.");
 131
 132                 if (!g_module_close(python_plugin_provider_module)) {
 133                         /*
 134                          * This occurs when the library is finalized: do
 135                          * NOT append an error cause.
 136                          */
 137                         BT_LOGE("Failed to close the Python plugin provider module: %s.",
 138                                 g_module_error());
 139                 }
 140
 141                 python_plugin_provider_module = NULL;
 142         }
 143 }
 144 #endif
 145
 146 uint64_t bt_plugin_set_get_plugin_count(struct bt_plugin_set *plugin_set)
 147 {
 148         BT_ASSERT_PRE_NON_NULL(plugin_set, "Plugin set");
 149         return (uint64_t) plugin_set->plugins->len;
 150 }
 151
 152 const struct bt_plugin *bt_plugin_set_borrow_plugin_by_index_const(
 153                 const struct bt_plugin_set *plugin_set, uint64_t index)
 154 {
 155         BT_ASSERT_PRE_NON_NULL(plugin_set, "Plugin set");
 156         BT_ASSERT_PRE_VALID_INDEX(index, plugin_set->plugins->len);
 157         return g_ptr_array_index(plugin_set->plugins, index);
 158 }
 159
 160 enum bt_plugin_find_all_from_static_status bt_plugin_find_all_from_static(
 161                 bt_bool fail_on_load_error,
 162                 const struct bt_plugin_set **plugin_set_out)
 163 {
 164         /* bt_plugin_so_create_all_from_static() logs errors */
 165         return bt_plugin_so_create_all_from_static(fail_on_load_error,
 166                 (void *) plugin_set_out);
 167 }
 168
 169 enum bt_plugin_find_all_from_file_status bt_plugin_find_all_from_file(
 170                 const char *path, bt_bool fail_on_load_error,
 171                 const struct bt_plugin_set **plugin_set_out)
 172 {
 173         enum bt_plugin_find_all_from_file_status status;
 174
 175         BT_ASSERT_PRE_NON_NULL(path, "Path");
 176         BT_ASSERT_PRE_NON_NULL(path, "Plugin set (output)");
 177         BT_LOGI("Creating plugins from file: path=\"%s\"", path);
 178
 179         /* Try shared object plugins */
 180         status = bt_plugin_so_create_all_from_file(path, fail_on_load_error,
 181                 (void *) plugin_set_out);
 182         if (status == BT_FUNC_STATUS_OK) {
 183                 BT_ASSERT(*plugin_set_out);
 184                 BT_ASSERT((*plugin_set_out)->plugins->len > 0);
 185                 goto end;
 186         } else if (status < 0) {
 187                 BT_ASSERT(!*plugin_set_out);
 188                 goto end;
 189         }
 190
 191         BT_ASSERT(status == BT_FUNC_STATUS_NOT_FOUND);
 192         BT_ASSERT(!*plugin_set_out);
 193
 194         /* Try Python plugins if support is available */
 195         status = init_python_plugin_provider();
 196         if (status < 0) {
 197                 /* init_python_plugin_provider() logs errors */
 198                 goto end;
 199         }
 200
 201         BT_ASSERT(status == BT_FUNC_STATUS_OK);
 202         status = BT_FUNC_STATUS_NOT_FOUND;
 203
 204         if (bt_plugin_python_create_all_from_file_sym) {
 205                 /* Python plugin provider exists */
 206                 status = bt_plugin_python_create_all_from_file_sym(path,
 207                         fail_on_load_error, (void *) plugin_set_out);
 208                 if (status == BT_FUNC_STATUS_OK) {
 209                         BT_ASSERT(*plugin_set_out);
 210                         BT_ASSERT((*plugin_set_out)->plugins->len > 0);
 211                         goto end;
 212                 } else if (status < 0) {
 213                         /*
 214                          * bt_plugin_python_create_all_from_file_sym()
 215                          * handles `fail_on_load_error` itself, so this
 216                          * is a "real" error.
 217                          */
 218                         BT_ASSERT(!*plugin_set_out);
 219                         goto end;
 220                 }
 221
 222                 BT_ASSERT(status == BT_FUNC_STATUS_NOT_FOUND);
 223                 BT_ASSERT(!*plugin_set_out);
 224         }
 225
 226 end:
 227         if (status == BT_FUNC_STATUS_OK) {
 228                 BT_LOGI("Created %u plugins from file: "
 229                         "path=\"%s\", count=%u, plugin-set-addr=%p",
 230                         (*plugin_set_out)->plugins->len, path,
 231                         (*plugin_set_out)->plugins->len,
 232                         *plugin_set_out);
 233         } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 234                 BT_LOGI("Found no plugins in file: path=\"%s\"", path);
 235         }
 236
 237         return status;
 238 }
 239
 240 static void destroy_gstring(void *data)
 241 {
 242         g_string_free(data, TRUE);
 243 }
 244
 245 enum bt_plugin_find_status bt_plugin_find(const char *plugin_name,
 246                 bt_bool fail_on_load_error, const struct bt_plugin **plugin_out)
 247 {
 248         const char *system_plugin_dir;
 249         char *home_plugin_dir = NULL;
 250         const char *envvar;
 251         const struct bt_plugin *plugin = NULL;
 252         const struct bt_plugin_set *plugin_set = NULL;
 253         GPtrArray *dirs = NULL;
 254         int ret;
 255         int status = BT_FUNC_STATUS_OK;
 256         size_t i, j;
 257
 258         BT_ASSERT_PRE_NON_NULL(plugin_name, "Name");
 259         BT_ASSERT_PRE_NON_NULL(plugin_out, "Plugin (output)");
 260         BT_LOGI("Finding named plugin in standard directories and built-in plugins: "
 261                 "name=\"%s\"", plugin_name);
 262         dirs = g_ptr_array_new_with_free_func((GDestroyNotify) destroy_gstring);
 263         if (!dirs) {
 264                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GPtrArray.");
 265                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 266                 goto end;
 267         }
 268
 269         /*
 270          * Search order is:
 271          *
 272          * 1. BABELTRACE_PLUGIN_PATH environment variable
 273          *    (colon-separated list of directories)
 274          * 2. ~/.local/lib/babeltrace2/plugins
 275          * 3. Default system directory for Babeltrace plugins, usually
 276          *    /usr/lib/babeltrace2/plugins or
 277          *    /usr/local/lib/babeltrace2/plugins if installed
 278          *    locally
 279          * 4. Built-in plugins (static)
 280          *
 281          * Directories are searched non-recursively.
 282          */
 283         envvar = getenv("BABELTRACE_PLUGIN_PATH");
 284         if (envvar) {
 285                 ret = bt_common_append_plugin_path_dirs(envvar, dirs);
 286                 if (ret) {
 287                         BT_LIB_LOGE_APPEND_CAUSE(
 288                                 "Failed to append plugin path to array of directories.");
 289                         status = BT_FUNC_STATUS_MEMORY_ERROR;
 290                         goto end;
 291                 }
 292         }
 293
 294         home_plugin_dir = bt_common_get_home_plugin_path(BT_LOG_OUTPUT_LEVEL);
 295         if (home_plugin_dir) {
 296                 GString *home_plugin_dir_str = g_string_new(home_plugin_dir);
 297
 298                 if (!home_plugin_dir_str) {
 299                         BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GString.");
 300                         status = BT_FUNC_STATUS_MEMORY_ERROR;
 301                         goto end;
 302                 }
 303
 304                 g_ptr_array_add(dirs, home_plugin_dir_str);
 305         }
 306
 307         system_plugin_dir = bt_common_get_system_plugin_path();
 308         if (system_plugin_dir) {
 309                 GString *system_plugin_dir_str =
 310                         g_string_new(system_plugin_dir);
 311
 312                 if (!system_plugin_dir_str) {
 313                         BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GString.");
 314                         status = BT_FUNC_STATUS_MEMORY_ERROR;
 315                         goto end;
 316                 }
 317
 318                 g_ptr_array_add(dirs, system_plugin_dir_str);
 319         }
 320
 321         for (i = 0; i < dirs->len; i++) {
 322                 GString *dir = g_ptr_array_index(dirs, i);
 323
 324                 BT_OBJECT_PUT_REF_AND_RESET(plugin_set);
 325
 326                 /*
 327                  * Skip this if the directory does not exist because
 328                  * bt_plugin_find_all_from_dir() would log a warning.
 329                  */
 330                 if (!g_file_test(dir->str, G_FILE_TEST_IS_DIR)) {
 331                         BT_LOGI("Skipping nonexistent directory path: "
 332                                 "path=\"%s\"", dir->str);
 333                         continue;
 334                 }
 335
 336                 /* bt_plugin_find_all_from_dir() logs details/errors */
 337                 status = bt_plugin_find_all_from_dir(dir->str, BT_FALSE,
 338                         fail_on_load_error, &plugin_set);
 339                 if (status < 0) {
 340                         BT_ASSERT(!plugin_set);
 341                         goto end;
 342                 } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 343                         BT_ASSERT(!plugin_set);
 344                         BT_LOGI("No plugins found in directory: path=\"%s\"",
 345                                 dir->str);
 346                         continue;
 347                 }
 348
 349                 BT_ASSERT(status == BT_FUNC_STATUS_OK);
 350                 BT_ASSERT(plugin_set);
 351
 352                 for (j = 0; j < plugin_set->plugins->len; j++) {
 353                         const struct bt_plugin *candidate_plugin =
 354                                 g_ptr_array_index(plugin_set->plugins, j);
 355
 356                         if (strcmp(bt_plugin_get_name(candidate_plugin),
 357                                         plugin_name) == 0) {
 358                                 BT_LOGI("Plugin found in directory: name=\"%s\", path=\"%s\"",
 359                                         plugin_name, dir->str);
 360                                 *plugin_out = candidate_plugin;
 361                                 bt_object_get_no_null_check(*plugin_out);
 362                                 goto end;
 363                         }
 364                 }
 365
 366                 BT_LOGI("Plugin not found in directory: name=\"%s\", path=\"%s\"",
 367                         plugin_name, dir->str);
 368         }
 369
 370         BT_OBJECT_PUT_REF_AND_RESET(plugin_set);
 371         status = bt_plugin_find_all_from_static(fail_on_load_error,
 372                 &plugin_set);
 373         if (status < 0) {
 374                 BT_ASSERT(!plugin_set);
 375                 goto end;
 376         } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 377                 BT_ASSERT(!plugin_set);
 378                 BT_LOGI_STR("No plugins found in built-in plugins.");
 379                 goto end;
 380         }
 381
 382         BT_ASSERT(status == BT_FUNC_STATUS_OK);
 383         BT_ASSERT(plugin_set);
 384
 385         for (j = 0; j < plugin_set->plugins->len; j++) {
 386                 const struct bt_plugin *candidate_plugin =
 387                         g_ptr_array_index(plugin_set->plugins, j);
 388
 389                 if (strcmp(bt_plugin_get_name(candidate_plugin),
 390                                 plugin_name) == 0) {
 391                         BT_LOGI("Plugin found in built-in plugins: "
 392                                 "name=\"%s\"", plugin_name);
 393                         *plugin_out = candidate_plugin;
 394                         bt_object_get_no_null_check(*plugin_out);
 395                         goto end;
 396                 }
 397         }
 398
 399         status = BT_FUNC_STATUS_NOT_FOUND;
 400
 401 end:
 402         free(home_plugin_dir);
 403         bt_object_put_ref(plugin_set);
 404
 405         if (dirs) {
 406                 g_ptr_array_free(dirs, TRUE);
 407         }
 408
 409         if (status == BT_FUNC_STATUS_OK) {
 410                 BT_LIB_LOGI("Found plugin in standard directories and built-in plugins: "
 411                         "%!+l", plugin);
 412         } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 413                 BT_LOGI("No plugin found in standard directories and built-in plugins: "
 414                         "name=\"%s\"", plugin_name);
 415         }
 416
 417         return status;
 418 }
 419
 420 static struct {
 421         pthread_mutex_t lock;
 422         struct bt_plugin_set *plugin_set;
 423         bool recurse;
 424         bool fail_on_load_error;
 425         int status;
 426 } append_all_from_dir_info = {
 427         .lock = PTHREAD_MUTEX_INITIALIZER
 428 };
 429
 430 static
 431 int nftw_append_all_from_dir(const char *file,
 432                 const struct stat *sb, int flag, struct FTW *s)
 433 {
 434         int ret = 0;
 435         const char *name = file + s->base;
 436
 437         /* Check for recursion */
 438         if (!append_all_from_dir_info.recurse && s->level > 1) {
 439                 goto end;
 440         }
 441
 442         switch (flag) {
 443         case FTW_F:
 444         {
 445                 const struct bt_plugin_set *plugins_from_file = NULL;
 446
 447                 if (name[0] == '.') {
 448                         /* Skip hidden files */
 449                         BT_LOGI("Skipping hidden file: path=\"%s\"", file);
 450                         goto end;
 451                 }
 452
 453                 append_all_from_dir_info.status =
 454                         bt_plugin_find_all_from_file(file,
 455                                 append_all_from_dir_info.fail_on_load_error,
 456                                 &plugins_from_file);
 457                 if (append_all_from_dir_info.status == BT_FUNC_STATUS_OK) {
 458                         size_t j;
 459
 460                         BT_ASSERT(plugins_from_file);
 461
 462                         for (j = 0; j < plugins_from_file->plugins->len; j++) {
 463                                 struct bt_plugin *plugin =
 464                                         g_ptr_array_index(plugins_from_file->plugins, j);
 465
 466                                 BT_LIB_LOGI("Adding plugin to plugin set: "
 467                                         "plugin-path=\"%s\", %![plugin-]+l",
 468                                         file, plugin);
 469                                 bt_plugin_set_add_plugin(
 470                                         append_all_from_dir_info.plugin_set,
 471                                         plugin);
 472                         }
 473
 474                         bt_object_put_ref(plugins_from_file);
 475                         goto end;
 476                 } else if (append_all_from_dir_info.status < 0) {
 477                         /* bt_plugin_find_all_from_file() logs errors */
 478                         BT_ASSERT(!plugins_from_file);
 479                         ret = -1;
 480                         goto end;
 481                 }
 482
 483                 /*
 484                  * Not found in this file: this is no an error; continue
 485                  * walking the directories.
 486                  */
 487                 BT_ASSERT(!plugins_from_file);
 488                 BT_ASSERT(append_all_from_dir_info.status ==
 489                         BT_FUNC_STATUS_NOT_FOUND);
 490                 break;
 491         }
 492         case FTW_DNR:
 493                 /* Continue to next file / directory. */
 494                 BT_LOGI("Cannot enter directory: continuing: path=\"%s\"", file);
 495                 break;
 496         case FTW_NS:
 497                 /* Continue to next file / directory. */
 498                 BT_LOGI("Cannot get file information: continuing: path=\"%s\"", file);
 499                 break;
 500         }
 501
 502 end:
 503         return ret;
 504 }
 505
 506 static
 507 int bt_plugin_create_append_all_from_dir(struct bt_plugin_set *plugin_set,
 508                 const char *path, bt_bool recurse, bt_bool fail_on_load_error)
 509 {
 510         int nftw_flags = FTW_PHYS;
 511         int ret;
 512         int status;
 513         struct stat sb;
 514
 515         BT_ASSERT(plugin_set);
 516         BT_ASSERT(path);
 517         BT_ASSERT(strlen(path) < PATH_MAX);
 518
 519         /*
 520          * Make sure that path exists and is accessible.
 521          * This is necessary since Cygwin implementation of nftw() is not POSIX
 522          * compliant. Cygwin nftw() implementation does not fail on non-existent
 523          * path with ENOENT. Instead, it flags the directory as FTW_NS. FTW_NS during
 524          * nftw_append_all_from_dir is not treated as an error since we are
 525          * traversing the tree for plugin discovery.
 526          */
 527         if (stat(path, &sb)) {
 528                 BT_LOGW_ERRNO("Cannot open directory",
 529                         ": path=\"%s\", recurse=%d",
 530                         path, recurse);
 531                 (void) BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_UNKNOWN(
 532                         "Babeltrace library",
 533                         "Cannot open directory: path=\"%s\", recurse=%d",
 534                         path, recurse);
 535                 status = BT_FUNC_STATUS_ERROR;
 536                 goto end;
 537         }
 538
 539         pthread_mutex_lock(&append_all_from_dir_info.lock);
 540         append_all_from_dir_info.plugin_set = plugin_set;
 541         append_all_from_dir_info.recurse = recurse;
 542         append_all_from_dir_info.status = BT_FUNC_STATUS_OK;
 543         append_all_from_dir_info.fail_on_load_error = fail_on_load_error;
 544         ret = nftw(path, nftw_append_all_from_dir,
 545                 APPEND_ALL_FROM_DIR_NFDOPEN_MAX, nftw_flags);
 546         append_all_from_dir_info.plugin_set = NULL;
 547         status = append_all_from_dir_info.status;
 548         pthread_mutex_unlock(&append_all_from_dir_info.lock);
 549         if (ret) {
 550                 BT_LIB_LOGW_APPEND_CAUSE("Failed to walk directory",
 551                         ": path=\"%s\", recurse=%d",
 552                         path, recurse);
 553                 status = BT_FUNC_STATUS_ERROR;
 554                 goto end;
 555         }
 556
 557         if (status == BT_FUNC_STATUS_NOT_FOUND) {
 558                 /*
 559                  * We're just appending in this function; even if
 560                  * nothing was found, it's still okay from the caller's
 561                  * perspective.
 562                  */
 563                 status = BT_FUNC_STATUS_OK;
 564         }
 565
 566 end:
 567         return status;
 568 }
 569
 570 enum bt_plugin_find_all_from_dir_status bt_plugin_find_all_from_dir(
 571                 const char *path, bt_bool recurse, bt_bool fail_on_load_error,
 572                 const struct bt_plugin_set **plugin_set_out)
 573 {
 574         enum bt_plugin_find_all_from_dir_status status =
 575                 BT_FUNC_STATUS_OK;
 576
 577         BT_ASSERT_PRE_NON_NULL(plugin_set_out, "Plugin set (output)");
 578         BT_LOGI("Creating all plugins in directory: path=\"%s\", recurse=%d",
 579                 path, recurse);
 580         *plugin_set_out = bt_plugin_set_create();
 581         if (!*plugin_set_out) {
 582                 BT_LIB_LOGE_APPEND_CAUSE("Cannot create empty plugin set.");
 583                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 584                 goto error;
 585         }
 586
 587         /*
 588          * Append found plugins to array (never returns
 589          * `BT_FUNC_STATUS_NOT_FOUND`)
 590          */
 591         status = bt_plugin_create_append_all_from_dir((void *) *plugin_set_out,
 592                 path, recurse, fail_on_load_error);
 593         if (status < 0) {
 594                 /*
 595                  * bt_plugin_create_append_all_from_dir() handles
 596                  * `fail_on_load_error`, so this is a "real" error.
 597                  */
 598                 BT_LIB_LOGE_APPEND_CAUSE(
 599                         "Cannot append plugins found in directory: "
 600                         "path=\"%s\", status=%s",
 601                         path, bt_common_func_status_string(status));
 602                 goto error;
 603         }
 604
 605         BT_ASSERT(status == BT_FUNC_STATUS_OK);
 606
 607         if ((*plugin_set_out)->plugins->len == 0) {
 608                 /* Nothing was appended: not found */
 609                 BT_LOGI("No plugins found in directory: path=\"%s\"", path);
 610                 status = BT_FUNC_STATUS_NOT_FOUND;
 611                 goto error;
 612         }
 613
 614         BT_LOGI("Created %u plugins from directory: count=%u, path=\"%s\"",
 615                 (*plugin_set_out)->plugins->len,
 616                 (*plugin_set_out)->plugins->len, path);
 617         goto end;
 618
 619 error:
 620         BT_ASSERT(status != BT_FUNC_STATUS_OK);
 621         BT_OBJECT_PUT_REF_AND_RESET(*plugin_set_out);
 622
 623 end:
 624         return status;
 625 }
 626
 627 const char *bt_plugin_get_name(const struct bt_plugin *plugin)
 628 {
 629         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 630         return plugin->info.name_set ? plugin->info.name->str : NULL;
 631 }
 632
 633 const char *bt_plugin_get_author(const struct bt_plugin *plugin)
 634 {
 635         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 636         return plugin->info.author_set ? plugin->info.author->str : NULL;
 637 }
 638
 639 const char *bt_plugin_get_license(const struct bt_plugin *plugin)
 640 {
 641         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 642         return plugin->info.license_set ? plugin->info.license->str : NULL;
 643 }
 644
 645 const char *bt_plugin_get_path(const struct bt_plugin *plugin)
 646 {
 647         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 648         return plugin->info.path_set ? plugin->info.path->str : NULL;
 649 }
 650
 651 const char *bt_plugin_get_description(const struct bt_plugin *plugin)
 652 {
 653         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 654         return plugin->info.description_set ?
 655                 plugin->info.description->str : NULL;
 656 }
 657
 658 enum bt_property_availability bt_plugin_get_version(const struct bt_plugin *plugin,
 659                 unsigned int *major, unsigned int *minor, unsigned int *patch,
 660                 const char **extra)
 661 {
 662         enum bt_property_availability avail =
 663                 BT_PROPERTY_AVAILABILITY_AVAILABLE;
 664
 665         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 666
 667         if (!plugin->info.version_set) {
 668                 BT_LIB_LOGD("Plugin's version is not set: %!+l", plugin);
 669                 avail = BT_PROPERTY_AVAILABILITY_NOT_AVAILABLE;
 670                 goto end;
 671         }
 672
 673         if (major) {
 674                 *major = plugin->info.version.major;
 675         }
 676
 677         if (minor) {
 678                 *minor = plugin->info.version.minor;
 679         }
 680
 681         if (patch) {
 682                 *patch = plugin->info.version.patch;
 683         }
 684
 685         if (extra) {
 686                 *extra = plugin->info.version.extra->str;
 687         }
 688
 689 end:
 690         return avail;
 691 }
 692
 693 uint64_t bt_plugin_get_source_component_class_count(const struct bt_plugin *plugin)
 694 {
 695         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 696         return (uint64_t) plugin->src_comp_classes->len;
 697 }
 698
 699 uint64_t bt_plugin_get_filter_component_class_count(const struct bt_plugin *plugin)
 700 {
 701         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 702         return (uint64_t) plugin->flt_comp_classes->len;
 703 }
 704
 705 uint64_t bt_plugin_get_sink_component_class_count(const struct bt_plugin *plugin)
 706 {
 707         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 708         return (uint64_t) plugin->sink_comp_classes->len;
 709 }
 710
 711 static inline
 712 struct bt_component_class *borrow_component_class_by_index(
 713                 const struct bt_plugin *plugin, GPtrArray *comp_classes,
 714                 uint64_t index)
 715 {
 716         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 717         BT_ASSERT_PRE_VALID_INDEX(index, comp_classes->len);
 718         return g_ptr_array_index(comp_classes, index);
 719 }
 720
 721 const struct bt_component_class_source *
 722 bt_plugin_borrow_source_component_class_by_index_const(
 723                 const struct bt_plugin *plugin, uint64_t index)
 724 {
 725         return (const void *) borrow_component_class_by_index(plugin,
 726                 plugin->src_comp_classes, index);
 727 }
 728
 729 const struct bt_component_class_filter *
 730 bt_plugin_borrow_filter_component_class_by_index_const(
 731                 const struct bt_plugin *plugin, uint64_t index)
 732 {
 733         return (const void *) borrow_component_class_by_index(plugin,
 734                 plugin->flt_comp_classes, index);
 735 }
 736
 737 const struct bt_component_class_sink *
 738 bt_plugin_borrow_sink_component_class_by_index_const(
 739                 const struct bt_plugin *plugin, uint64_t index)
 740 {
 741         return (const void *) borrow_component_class_by_index(plugin,
 742                 plugin->sink_comp_classes, index);
 743 }
 744
 745 static inline
 746 struct bt_component_class *borrow_component_class_by_name(
 747                 const struct bt_plugin *plugin, GPtrArray *comp_classes,
 748                 const char *name)
 749 {
 750         struct bt_component_class *comp_class = NULL;
 751         size_t i;
 752
 753         BT_ASSERT_PRE_NON_NULL(plugin, "Plugin");
 754         BT_ASSERT_PRE_NON_NULL(name, "Name");
 755
 756         for (i = 0; i < comp_classes->len; i++) {
 757                 struct bt_component_class *comp_class_candidate =
 758                         g_ptr_array_index(comp_classes, i);
 759                 const char *comp_class_cand_name =
 760                         bt_component_class_get_name(comp_class_candidate);
 761
 762                 BT_ASSERT(comp_class_cand_name);
 763
 764                 if (strcmp(name, comp_class_cand_name) == 0) {
 765                         comp_class = comp_class_candidate;
 766                         break;
 767                 }
 768         }
 769
 770         return comp_class;
 771 }
 772
 773 const struct bt_component_class_source *
 774 bt_plugin_borrow_source_component_class_by_name_const(
 775                 const struct bt_plugin *plugin, const char *name)
 776 {
 777         return (const void *) borrow_component_class_by_name(plugin,
 778                 plugin->src_comp_classes, name);
 779 }
 780
 781 const struct bt_component_class_filter *
 782 bt_plugin_borrow_filter_component_class_by_name_const(
 783                 const struct bt_plugin *plugin, const char *name)
 784 {
 785         return (const void *) borrow_component_class_by_name(plugin,
 786                 plugin->flt_comp_classes, name);
 787 }
 788
 789 const struct bt_component_class_sink *
 790 bt_plugin_borrow_sink_component_class_by_name_const(
 791                 const struct bt_plugin *plugin, const char *name)
 792 {
 793         return (const void *) borrow_component_class_by_name(plugin,
 794                 plugin->sink_comp_classes, name);
 795 }
 796
 797 void bt_plugin_get_ref(const struct bt_plugin *plugin)
 798 {
 799         bt_object_get_ref(plugin);
 800 }
 801
 802 void bt_plugin_put_ref(const struct bt_plugin *plugin)
 803 {
 804         bt_object_put_ref(plugin);
 805 }
 806
 807 void bt_plugin_set_get_ref(const struct bt_plugin_set *plugin_set)
 808 {
 809         bt_object_get_ref(plugin_set);
 810 }
 811
 812 void bt_plugin_set_put_ref(const struct bt_plugin_set *plugin_set)
 813 {
 814         bt_object_put_ref(plugin_set);
 815 }