src/lib/plugin/plugin.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright 2017-2018 Philippe Proulx <pproulx@efficios.com>
   5  * Copyright 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   6  */
   7
   8 #define BT_LOG_TAG "LIB/PLUGIN"
   9 #include "lib/logging.h"
  10
  11 #include "common/assert.h"
  12 #include "lib/assert-cond.h"
  13 #include "common/macros.h"
  14 #include "compat/compiler.h"
  15 #include "compat/limits.h"
  16 #include "common/common.h"
  17 #include <babeltrace2/plugin/plugin-loading.h>
  18 #include <babeltrace2/graph/component-class.h>
  19 #include <babeltrace2/error-reporting.h>
  20 #include "lib/graph/component-class.h"
  21 #include <babeltrace2/types.h>
  22 #include <glib.h>
  23 #include <unistd.h>
  24 #include <stdbool.h>
  25 #include <stdlib.h>
  26 #include <stdint.h>
  27 #include <inttypes.h>
  28 #include <sys/stat.h>
  29 #include <ftw.h>
  30 #include <pthread.h>
  31
  32 #include "plugin.h"
  33 #include "plugin-so.h"
  34 #include "lib/func-status.h"
  35
  36 #define PYTHON_PLUGIN_PROVIDER_FILENAME "babeltrace2-python-plugin-provider." G_MODULE_SUFFIX
  37 #define PYTHON_PLUGIN_PROVIDER_DIR      BABELTRACE_PLUGIN_PROVIDERS_DIR
  38 #define PYTHON_PLUGIN_PROVIDER_SYM_NAME bt_plugin_python_create_all_from_file
  39 #define PYTHON_PLUGIN_PROVIDER_SYM_NAME_STR     G_STRINGIFY(PYTHON_PLUGIN_PROVIDER_SYM_NAME)
  40
  41 #define APPEND_ALL_FROM_DIR_NFDOPEN_MAX 8
  42
  43 /* Declare here to make sure definition in both ifdef branches are in sync. */
  44 static
  45 int init_python_plugin_provider(void);
  46 typedef int (*create_all_from_file_sym_type)(
  47                 const char *path,
  48                 bool fail_on_load_error,
  49                 struct bt_plugin_set **plugin_set_out);
  50
  51 #ifdef BT_BUILT_IN_PYTHON_PLUGIN_SUPPORT
  52 #include <plugin/python-plugin-provider.h>
  53
  54 static
  55 create_all_from_file_sym_type
  56         bt_plugin_python_create_all_from_file_sym =
  57                         bt_plugin_python_create_all_from_file;
  58
  59 static
  60 int init_python_plugin_provider(void)
  61 {
  62 }
  63 #else /* BT_BUILT_IN_PYTHON_PLUGIN_SUPPORT */
  64 static GModule *python_plugin_provider_module;
  65
  66 static
  67 create_all_from_file_sym_type bt_plugin_python_create_all_from_file_sym;
  68
  69 static
  70 int init_python_plugin_provider(void) {
  71         int status = BT_FUNC_STATUS_OK;
  72         const char *provider_dir_envvar;
  73         static const char * const provider_dir_envvar_name = "LIBBABELTRACE2_PLUGIN_PROVIDER_DIR";
  74         char *provider_path = NULL;
  75
  76         if (bt_plugin_python_create_all_from_file_sym) {
  77                 goto end;
  78         }
  79
  80         BT_LOGI_STR("Loading Python plugin provider module.");
  81
  82         provider_dir_envvar = getenv(provider_dir_envvar_name);
  83         if (provider_dir_envvar) {
  84                 provider_path = g_build_filename(provider_dir_envvar,
  85                         PYTHON_PLUGIN_PROVIDER_FILENAME, NULL);
  86                 BT_LOGI("Using `%s` environment variable to find the Python "
  87                         "plugin provider: path=\"%s\"", provider_dir_envvar_name,
  88                         provider_path);
  89         } else {
  90                 provider_path = g_build_filename(PYTHON_PLUGIN_PROVIDER_DIR,
  91                         PYTHON_PLUGIN_PROVIDER_FILENAME, NULL);
  92                 BT_LOGI("Using default path (`%s` environment variable is not "
  93                         "set) to find the Python plugin provider: path=\"%s\"",
  94                         provider_dir_envvar_name, provider_path);
  95         }
  96
  97         python_plugin_provider_module = g_module_open(provider_path, 0);
  98         if (!python_plugin_provider_module) {
  99                 /*
 100                  * This is not an error. The whole point of having an
 101                  * external Python plugin provider is that it can be
 102                  * missing and the Babeltrace library still works.
 103                  */
 104                 BT_LOGI("Cannot open `%s`: %s: continuing without Python plugin support.",
 105                         provider_path, g_module_error());
 106                 goto end;
 107         }
 108
 109         if (!g_module_symbol(python_plugin_provider_module,
 110                         PYTHON_PLUGIN_PROVIDER_SYM_NAME_STR,
 111                         (gpointer) &bt_plugin_python_create_all_from_file_sym)) {
 112                 /*
 113                  * This is an error because, since we found the Python
 114                  * plugin provider shared object, we expect this symbol
 115                  * to exist.
 116                  */
 117                 BT_LIB_LOGE_APPEND_CAUSE(
 118                         "Cannot find the Python plugin provider loading symbol: "
 119                         "%s: continuing without Python plugin support: "
 120                         "file=\"%s\", symbol=\"%s\"",
 121                         g_module_error(),
 122                         provider_path,
 123                         PYTHON_PLUGIN_PROVIDER_SYM_NAME_STR);
 124                 status = BT_FUNC_STATUS_ERROR;
 125                 goto end;
 126         }
 127
 128         BT_LOGI("Loaded Python plugin provider module: addr=%p",
 129                 python_plugin_provider_module);
 130
 131 end:
 132         g_free(provider_path);
 133
 134         return status;
 135 }
 136
 137 __attribute__((destructor)) static
 138 void fini_python_plugin_provider(void) {
 139         if (python_plugin_provider_module) {
 140                 BT_LOGI("Unloading Python plugin provider module.");
 141
 142                 if (!g_module_close(python_plugin_provider_module)) {
 143                         /*
 144                          * This occurs when the library is finalized: do
 145                          * NOT append an error cause.
 146                          */
 147                         BT_LOGE("Failed to close the Python plugin provider module: %s.",
 148                                 g_module_error());
 149                 }
 150
 151                 python_plugin_provider_module = NULL;
 152         }
 153 }
 154 #endif
 155
 156 BT_EXPORT
 157 uint64_t bt_plugin_set_get_plugin_count(const struct bt_plugin_set *plugin_set)
 158 {
 159         BT_ASSERT_PRE_DEV_PLUGIN_SET_NON_NULL(plugin_set);
 160         return (uint64_t) plugin_set->plugins->len;
 161 }
 162
 163 BT_EXPORT
 164 const struct bt_plugin *bt_plugin_set_borrow_plugin_by_index_const(
 165                 const struct bt_plugin_set *plugin_set, uint64_t index)
 166 {
 167         BT_ASSERT_PRE_DEV_PLUGIN_SET_NON_NULL(plugin_set);
 168         BT_ASSERT_PRE_DEV_VALID_INDEX(index, plugin_set->plugins->len);
 169         return g_ptr_array_index(plugin_set->plugins, index);
 170 }
 171
 172 BT_EXPORT
 173 enum bt_plugin_find_all_from_static_status bt_plugin_find_all_from_static(
 174                 bt_bool fail_on_load_error,
 175                 const struct bt_plugin_set **plugin_set_out)
 176 {
 177         BT_ASSERT_PRE_NO_ERROR();
 178
 179         /* bt_plugin_so_create_all_from_static() logs errors */
 180         return bt_plugin_so_create_all_from_static(fail_on_load_error,
 181                 (void *) plugin_set_out);
 182 }
 183
 184 BT_EXPORT
 185 enum bt_plugin_find_all_from_file_status bt_plugin_find_all_from_file(
 186                 const char *path, bt_bool fail_on_load_error,
 187                 const struct bt_plugin_set **plugin_set_out)
 188 {
 189         enum bt_plugin_find_all_from_file_status status;
 190
 191         BT_ASSERT_PRE_NO_ERROR();
 192         BT_ASSERT_PRE_NON_NULL("path", path, "Path");
 193         BT_ASSERT_PRE_PLUGIN_SET_OUT_NON_NULL(path);
 194         BT_LOGI("Creating plugins from file: path=\"%s\"", path);
 195
 196         /* Try shared object plugins */
 197         status = bt_plugin_so_create_all_from_file(path, fail_on_load_error,
 198                 (void *) plugin_set_out);
 199         if (status == BT_FUNC_STATUS_OK) {
 200                 BT_ASSERT(*plugin_set_out);
 201                 BT_ASSERT((*plugin_set_out)->plugins->len > 0);
 202                 goto end;
 203         } else if (status < 0) {
 204                 BT_ASSERT(!*plugin_set_out);
 205                 goto end;
 206         }
 207
 208         BT_ASSERT(status == BT_FUNC_STATUS_NOT_FOUND);
 209         BT_ASSERT(!*plugin_set_out);
 210
 211         /* Try Python plugins if support is available */
 212         status = init_python_plugin_provider();
 213         if (status < 0) {
 214                 /* init_python_plugin_provider() logs errors */
 215                 goto end;
 216         }
 217
 218         BT_ASSERT(status == BT_FUNC_STATUS_OK);
 219         status = BT_FUNC_STATUS_NOT_FOUND;
 220
 221         if (bt_plugin_python_create_all_from_file_sym) {
 222                 /* Python plugin provider exists */
 223                 status = bt_plugin_python_create_all_from_file_sym(path,
 224                         fail_on_load_error, (void *) plugin_set_out);
 225                 if (status == BT_FUNC_STATUS_OK) {
 226                         BT_ASSERT(*plugin_set_out);
 227                         BT_ASSERT((*plugin_set_out)->plugins->len > 0);
 228                         goto end;
 229                 } else if (status < 0) {
 230                         /*
 231                          * bt_plugin_python_create_all_from_file_sym()
 232                          * handles `fail_on_load_error` itself, so this
 233                          * is a "real" error.
 234                          */
 235                         BT_ASSERT(!*plugin_set_out);
 236                         goto end;
 237                 }
 238
 239                 BT_ASSERT(status == BT_FUNC_STATUS_NOT_FOUND);
 240                 BT_ASSERT(!*plugin_set_out);
 241         }
 242
 243 end:
 244         if (status == BT_FUNC_STATUS_OK) {
 245                 BT_LOGI("Created %u plugins from file: "
 246                         "path=\"%s\", count=%u, plugin-set-addr=%p",
 247                         (*plugin_set_out)->plugins->len, path,
 248                         (*plugin_set_out)->plugins->len,
 249                         *plugin_set_out);
 250         } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 251                 BT_LOGI("Found no plugins in file: path=\"%s\"", path);
 252         }
 253
 254         return status;
 255 }
 256
 257 static
 258 void destroy_gstring(void *data)
 259 {
 260         g_string_free(data, TRUE);
 261 }
 262
 263 BT_EXPORT
 264 enum bt_plugin_find_all_status bt_plugin_find_all(bt_bool find_in_std_env_var,
 265                 bt_bool find_in_user_dir, bt_bool find_in_sys_dir,
 266                 bt_bool find_in_static, bt_bool fail_on_load_error,
 267                 const struct bt_plugin_set **plugin_set_out)
 268 {
 269         char *home_plugin_dir = NULL;
 270         const struct bt_plugin_set *plugin_set = NULL;
 271         GPtrArray *dirs = NULL;
 272         int ret;
 273         int status = BT_FUNC_STATUS_OK;
 274         uint64_t dir_i, plugin_i;
 275
 276         BT_ASSERT_PRE_NO_ERROR();
 277         BT_ASSERT_PRE_PLUGIN_SET_OUT_NON_NULL(plugin_set_out);
 278         BT_LOGI("Finding all plugins in standard directories and built-in plugins: "
 279                 "find-in-std-env-var=%d, find-in-user-dir=%d, "
 280                 "find-in-sys-dir=%d, find-in-static=%d",
 281                 find_in_std_env_var, find_in_user_dir, find_in_sys_dir,
 282                 find_in_static);
 283         dirs = g_ptr_array_new_with_free_func((GDestroyNotify) destroy_gstring);
 284         if (!dirs) {
 285                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GPtrArray.");
 286                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 287                 goto end;
 288         }
 289
 290         *plugin_set_out = bt_plugin_set_create();
 291         if (!*plugin_set_out) {
 292                 BT_LIB_LOGE_APPEND_CAUSE("Cannot create empty plugin set.");
 293                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 294                 goto end;
 295         }
 296
 297         /*
 298          * Search order is:
 299          *
 300          * 1. `BABELTRACE_PLUGIN_PATH` environment variable
 301          *    (colon-separated list of directories)
 302          * 2. `~/.local/lib/babeltrace2/plugins`
 303          * 3. Default system directory for Babeltrace plugins, usually
 304          *    `/usr/lib/babeltrace2/plugins` or
 305          *    `/usr/local/lib/babeltrace2/plugins` if installed locally
 306          * 4. Built-in plugins (static)
 307          *
 308          * Directories are searched non-recursively.
 309          */
 310         if (find_in_std_env_var) {
 311                 const char *envvar = getenv("BABELTRACE_PLUGIN_PATH");
 312
 313                 if (envvar) {
 314                         ret = bt_common_append_plugin_path_dirs(envvar, dirs);
 315                         if (ret) {
 316                                 BT_LIB_LOGE_APPEND_CAUSE(
 317                                         "Failed to append plugin path to array of directories.");
 318                                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 319                                 goto end;
 320                         }
 321                 }
 322         }
 323
 324         if (find_in_user_dir) {
 325                 home_plugin_dir = bt_common_get_home_plugin_path(
 326                         BT_LOG_OUTPUT_LEVEL);
 327                 if (home_plugin_dir) {
 328                         GString *home_plugin_dir_str = g_string_new(
 329                                 home_plugin_dir);
 330
 331                         if (!home_plugin_dir_str) {
 332                                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GString.");
 333                                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 334                                 goto end;
 335                         }
 336
 337                         g_ptr_array_add(dirs, home_plugin_dir_str);
 338                 }
 339         }
 340
 341         if (find_in_sys_dir) {
 342                 const char *system_plugin_dir =
 343                         bt_common_get_system_plugin_path();
 344
 345                 if (system_plugin_dir) {
 346                         GString *system_plugin_dir_str =
 347                                 g_string_new(system_plugin_dir);
 348
 349                         if (!system_plugin_dir_str) {
 350                                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GString.");
 351                                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 352                                 goto end;
 353                         }
 354
 355                         g_ptr_array_add(dirs, system_plugin_dir_str);
 356                 }
 357         }
 358
 359         for (dir_i = 0; dir_i < dirs->len; dir_i++) {
 360                 GString *dir = dirs->pdata[dir_i];
 361
 362                 BT_OBJECT_PUT_REF_AND_RESET(plugin_set);
 363
 364                 /*
 365                  * Skip this if the directory does not exist because
 366                  * bt_plugin_find_all_from_dir() would log a warning.
 367                  */
 368                 if (!g_file_test(dir->str, G_FILE_TEST_IS_DIR)) {
 369                         BT_LOGI("Skipping nonexistent directory path: "
 370                                 "path=\"%s\"", dir->str);
 371                         continue;
 372                 }
 373
 374                 /* bt_plugin_find_all_from_dir() logs details/errors */
 375                 status = bt_plugin_find_all_from_dir(dir->str, BT_FALSE,
 376                         fail_on_load_error, &plugin_set);
 377                 if (status < 0) {
 378                         BT_ASSERT(!plugin_set);
 379                         goto end;
 380                 } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 381                         BT_ASSERT(!plugin_set);
 382                         BT_LOGI("No plugins found in directory: path=\"%s\"",
 383                                 dir->str);
 384                         continue;
 385                 }
 386
 387                 BT_ASSERT(status == BT_FUNC_STATUS_OK);
 388                 BT_ASSERT(plugin_set);
 389                 BT_LOGI("Found plugins in directory: path=\"%s\", count=%u",
 390                         dir->str, plugin_set->plugins->len);
 391
 392                 for (plugin_i = 0; plugin_i < plugin_set->plugins->len;
 393                                 plugin_i++) {
 394                         bt_plugin_set_add_plugin((void *) *plugin_set_out,
 395                                 plugin_set->plugins->pdata[plugin_i]);
 396                 }
 397         }
 398
 399         if (find_in_static) {
 400                 BT_OBJECT_PUT_REF_AND_RESET(plugin_set);
 401                 status = bt_plugin_find_all_from_static(fail_on_load_error,
 402                         &plugin_set);
 403                 if (status < 0) {
 404                         BT_ASSERT(!plugin_set);
 405                         goto end;
 406                 } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 407                         BT_ASSERT(!plugin_set);
 408                         BT_LOGI_STR("No plugins found in built-in plugins.");
 409                         goto end;
 410                 }
 411
 412                 BT_ASSERT(status == BT_FUNC_STATUS_OK);
 413                 BT_ASSERT(plugin_set);
 414                 BT_LOGI("Found built-in plugins: count=%u",
 415                         plugin_set->plugins->len);
 416
 417                 for (plugin_i = 0; plugin_i < plugin_set->plugins->len;
 418                                 plugin_i++) {
 419                         bt_plugin_set_add_plugin((void *) *plugin_set_out,
 420                                 plugin_set->plugins->pdata[plugin_i]);
 421                 }
 422         }
 423
 424 end:
 425         free(home_plugin_dir);
 426         bt_object_put_ref(plugin_set);
 427
 428         if (dirs) {
 429                 g_ptr_array_free(dirs, TRUE);
 430         }
 431
 432         if (status < 0) {
 433                 BT_OBJECT_PUT_REF_AND_RESET(*plugin_set_out);
 434         } else {
 435                 BT_ASSERT(*plugin_set_out);
 436
 437                 if ((*plugin_set_out)->plugins->len > 0) {
 438                         BT_LOGI("Found plugins in standard directories and built-in plugins: "
 439                                 "count=%u", (*plugin_set_out)->plugins->len);
 440                         status = BT_FUNC_STATUS_OK;
 441                 } else {
 442                         BT_LOGI_STR("No plugins found in standard directories and built-in plugins.");
 443                         status = BT_FUNC_STATUS_NOT_FOUND;
 444                         BT_OBJECT_PUT_REF_AND_RESET(*plugin_set_out);
 445                 }
 446         }
 447
 448         return status;
 449 }
 450
 451 BT_EXPORT
 452 enum bt_plugin_find_status bt_plugin_find(const char *plugin_name,
 453                 bt_bool find_in_std_env_var, bt_bool find_in_user_dir,
 454                 bt_bool find_in_sys_dir, bt_bool find_in_static,
 455                 bt_bool fail_on_load_error, const struct bt_plugin **plugin_out)
 456 {
 457         enum bt_plugin_find_status status;
 458         const struct bt_plugin_set *plugin_set = NULL;
 459         uint64_t i;
 460
 461         BT_ASSERT_PRE_NO_ERROR();
 462         BT_ASSERT_PRE_NAME_NON_NULL(plugin_name);
 463         BT_ASSERT_PRE_PLUGIN_OUT_NON_NULL(plugin_out);
 464         BT_LOGI("Finding named plugin in standard directories and built-in plugins: "
 465                 "name=\"%s\", find-in-std-env-var=%d, find-in-user-dir=%d, "
 466                 "find-in-sys-dir=%d, find-in-static=%d",
 467                 plugin_name, find_in_std_env_var, find_in_user_dir,
 468                 find_in_sys_dir, find_in_static);
 469         status = (enum bt_plugin_find_status) bt_plugin_find_all(find_in_std_env_var, find_in_user_dir,
 470                 find_in_sys_dir, find_in_static, fail_on_load_error,
 471                 &plugin_set);
 472         if (status != BT_FUNC_STATUS_OK) {
 473                 BT_ASSERT(!plugin_set);
 474                 goto end;
 475         }
 476
 477         BT_ASSERT(plugin_set);
 478
 479         for (i = 0; i < plugin_set->plugins->len; i++) {
 480                 const struct bt_plugin *plugin = plugin_set->plugins->pdata[i];
 481
 482                 if (strcmp(plugin->info.name->str, plugin_name) == 0) {
 483                         *plugin_out = plugin;
 484                         bt_object_get_ref_no_null_check(*plugin_out);
 485                         goto end;
 486                 }
 487         }
 488
 489         status = BT_FUNC_STATUS_NOT_FOUND;
 490
 491 end:
 492         if (status == BT_FUNC_STATUS_OK) {
 493                 BT_ASSERT(*plugin_out);
 494                 BT_LIB_LOGI("Found plugin in standard directories and built-in plugins: "
 495                         "%!+l", *plugin_out);
 496         } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 497                 BT_LOGI("No plugin found in standard directories and built-in plugins: "
 498                         "name=\"%s\"", plugin_name);
 499         }
 500
 501         bt_plugin_set_put_ref(plugin_set);
 502
 503         return status;
 504 }
 505
 506 static struct {
 507         pthread_mutex_t lock;
 508         struct bt_plugin_set *plugin_set;
 509         bool recurse;
 510         bool fail_on_load_error;
 511         int status;
 512 } append_all_from_dir_info = {
 513         .lock = PTHREAD_MUTEX_INITIALIZER
 514 };
 515
 516 static
 517 int nftw_append_all_from_dir(const char *file,
 518                 const struct stat *sb __attribute__((unused)),
 519                 int flag, struct FTW *s)
 520 {
 521         int ret = 0;
 522         const char *name = file + s->base;
 523
 524         /* Check for recursion */
 525         if (!append_all_from_dir_info.recurse && s->level > 1) {
 526                 goto end;
 527         }
 528
 529         switch (flag) {
 530         case FTW_F:
 531         {
 532                 const struct bt_plugin_set *plugins_from_file = NULL;
 533
 534                 if (name[0] == '.') {
 535                         /* Skip hidden files */
 536                         BT_LOGI("Skipping hidden file: path=\"%s\"", file);
 537                         goto end;
 538                 }
 539
 540                 append_all_from_dir_info.status =
 541                         bt_plugin_find_all_from_file(file,
 542                                 append_all_from_dir_info.fail_on_load_error,
 543                                 &plugins_from_file);
 544                 if (append_all_from_dir_info.status == BT_FUNC_STATUS_OK) {
 545                         size_t j;
 546
 547                         BT_ASSERT(plugins_from_file);
 548
 549                         for (j = 0; j < plugins_from_file->plugins->len; j++) {
 550                                 struct bt_plugin *plugin =
 551                                         g_ptr_array_index(plugins_from_file->plugins, j);
 552
 553                                 BT_LIB_LOGI("Adding plugin to plugin set: "
 554                                         "plugin-path=\"%s\", %![plugin-]+l",
 555                                         file, plugin);
 556                                 bt_plugin_set_add_plugin(
 557                                         append_all_from_dir_info.plugin_set,
 558                                         plugin);
 559                         }
 560
 561                         bt_object_put_ref(plugins_from_file);
 562                         goto end;
 563                 } else if (append_all_from_dir_info.status < 0) {
 564                         /* bt_plugin_find_all_from_file() logs errors */
 565                         BT_ASSERT(!plugins_from_file);
 566                         ret = -1;
 567                         goto end;
 568                 }
 569
 570                 /*
 571                  * Not found in this file: this is no an error; continue
 572                  * walking the directories.
 573                  */
 574                 BT_ASSERT(!plugins_from_file);
 575                 BT_ASSERT(append_all_from_dir_info.status ==
 576                         BT_FUNC_STATUS_NOT_FOUND);
 577                 break;
 578         }
 579         case FTW_DNR:
 580                 /* Continue to next file / directory. */
 581                 BT_LOGI("Cannot enter directory: continuing: path=\"%s\"", file);
 582                 break;
 583         case FTW_NS:
 584                 /* Continue to next file / directory. */
 585                 BT_LOGI("Cannot get file information: continuing: path=\"%s\"", file);
 586                 break;
 587         }
 588
 589 end:
 590         return ret;
 591 }
 592
 593 static
 594 int bt_plugin_create_append_all_from_dir(struct bt_plugin_set *plugin_set,
 595                 const char *path, bt_bool recurse, bt_bool fail_on_load_error)
 596 {
 597         int nftw_flags = FTW_PHYS;
 598         int ret;
 599         int status;
 600         struct stat sb;
 601
 602         BT_ASSERT(plugin_set);
 603         BT_ASSERT(path);
 604         BT_ASSERT(strlen(path) < PATH_MAX);
 605
 606         /*
 607          * Make sure that path exists and is accessible.
 608          * This is necessary since Cygwin implementation of nftw() is not POSIX
 609          * compliant. Cygwin nftw() implementation does not fail on non-existent
 610          * path with ENOENT. Instead, it flags the directory as FTW_NS. FTW_NS during
 611          * nftw_append_all_from_dir is not treated as an error since we are
 612          * traversing the tree for plugin discovery.
 613          */
 614         if (stat(path, &sb)) {
 615                 BT_LOGW_ERRNO("Cannot open directory",
 616                         ": path=\"%s\", recurse=%d",
 617                         path, recurse);
 618                 (void) BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_UNKNOWN(
 619                         BT_LIB_LOG_LIBBABELTRACE2_NAME,
 620                         "Cannot open directory: path=\"%s\", recurse=%d",
 621                         path, recurse);
 622                 status = BT_FUNC_STATUS_ERROR;
 623                 goto end;
 624         }
 625
 626         pthread_mutex_lock(&append_all_from_dir_info.lock);
 627         append_all_from_dir_info.plugin_set = plugin_set;
 628         append_all_from_dir_info.recurse = recurse;
 629         append_all_from_dir_info.status = BT_FUNC_STATUS_OK;
 630         append_all_from_dir_info.fail_on_load_error = fail_on_load_error;
 631         ret = nftw(path, nftw_append_all_from_dir,
 632                 APPEND_ALL_FROM_DIR_NFDOPEN_MAX, nftw_flags);
 633         append_all_from_dir_info.plugin_set = NULL;
 634         status = append_all_from_dir_info.status;
 635         pthread_mutex_unlock(&append_all_from_dir_info.lock);
 636         if (ret) {
 637                 BT_LIB_LOGW_APPEND_CAUSE("Failed to walk directory",
 638                         ": path=\"%s\", recurse=%d",
 639                         path, recurse);
 640                 status = BT_FUNC_STATUS_ERROR;
 641                 goto end;
 642         }
 643
 644         if (status == BT_FUNC_STATUS_NOT_FOUND) {
 645                 /*
 646                  * We're just appending in this function; even if
 647                  * nothing was found, it's still okay from the caller's
 648                  * perspective.
 649                  */
 650                 status = BT_FUNC_STATUS_OK;
 651         }
 652
 653 end:
 654         return status;
 655 }
 656
 657 BT_EXPORT
 658 enum bt_plugin_find_all_from_dir_status bt_plugin_find_all_from_dir(
 659                 const char *path, bt_bool recurse, bt_bool fail_on_load_error,
 660                 const struct bt_plugin_set **plugin_set_out)
 661 {
 662         enum bt_plugin_find_all_from_dir_status status =
 663                 BT_FUNC_STATUS_OK;
 664
 665         BT_ASSERT_PRE_NO_ERROR();
 666         BT_ASSERT_PRE_PLUGIN_SET_OUT_NON_NULL(plugin_set_out);
 667         BT_LOGI("Creating all plugins in directory: path=\"%s\", recurse=%d",
 668                 path, recurse);
 669         *plugin_set_out = bt_plugin_set_create();
 670         if (!*plugin_set_out) {
 671                 BT_LIB_LOGE_APPEND_CAUSE("Cannot create empty plugin set.");
 672                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 673                 goto error;
 674         }
 675
 676         /*
 677          * Append found plugins to array (never returns
 678          * `BT_FUNC_STATUS_NOT_FOUND`)
 679          */
 680         status = bt_plugin_create_append_all_from_dir((void *) *plugin_set_out,
 681                 path, recurse, fail_on_load_error);
 682         if (status < 0) {
 683                 /*
 684                  * bt_plugin_create_append_all_from_dir() handles
 685                  * `fail_on_load_error`, so this is a "real" error.
 686                  */
 687                 BT_LIB_LOGE_APPEND_CAUSE(
 688                         "Cannot append plugins found in directory: "
 689                         "path=\"%s\", status=%s",
 690                         path, bt_common_func_status_string(status));
 691                 goto error;
 692         }
 693
 694         BT_ASSERT(status == BT_FUNC_STATUS_OK);
 695
 696         if ((*plugin_set_out)->plugins->len == 0) {
 697                 /* Nothing was appended: not found */
 698                 BT_LOGI("No plugins found in directory: path=\"%s\"", path);
 699                 status = BT_FUNC_STATUS_NOT_FOUND;
 700                 goto error;
 701         }
 702
 703         BT_LOGI("Created %u plugins from directory: count=%u, path=\"%s\"",
 704                 (*plugin_set_out)->plugins->len,
 705                 (*plugin_set_out)->plugins->len, path);
 706         goto end;
 707
 708 error:
 709         BT_ASSERT(status != BT_FUNC_STATUS_OK);
 710         BT_OBJECT_PUT_REF_AND_RESET(*plugin_set_out);
 711
 712 end:
 713         return status;
 714 }
 715
 716 BT_EXPORT
 717 const char *bt_plugin_get_name(const struct bt_plugin *plugin)
 718 {
 719         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 720         return plugin->info.name_set ? plugin->info.name->str : NULL;
 721 }
 722
 723 BT_EXPORT
 724 const char *bt_plugin_get_author(const struct bt_plugin *plugin)
 725 {
 726         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 727         return plugin->info.author_set ? plugin->info.author->str : NULL;
 728 }
 729
 730 BT_EXPORT
 731 const char *bt_plugin_get_license(const struct bt_plugin *plugin)
 732 {
 733         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 734         return plugin->info.license_set ? plugin->info.license->str : NULL;
 735 }
 736
 737 BT_EXPORT
 738 const char *bt_plugin_get_path(const struct bt_plugin *plugin)
 739 {
 740         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 741         return plugin->info.path_set ? plugin->info.path->str : NULL;
 742 }
 743
 744 BT_EXPORT
 745 const char *bt_plugin_get_description(const struct bt_plugin *plugin)
 746 {
 747         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 748         return plugin->info.description_set ?
 749                 plugin->info.description->str : NULL;
 750 }
 751
 752 BT_EXPORT
 753 enum bt_property_availability bt_plugin_get_version(const struct bt_plugin *plugin,
 754                 unsigned int *major, unsigned int *minor, unsigned int *patch,
 755                 const char **extra)
 756 {
 757         enum bt_property_availability avail =
 758                 BT_PROPERTY_AVAILABILITY_AVAILABLE;
 759
 760         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 761
 762         if (!plugin->info.version_set) {
 763                 BT_LIB_LOGD("Plugin's version is not set: %!+l", plugin);
 764                 avail = BT_PROPERTY_AVAILABILITY_NOT_AVAILABLE;
 765                 goto end;
 766         }
 767
 768         if (major) {
 769                 *major = plugin->info.version.major;
 770         }
 771
 772         if (minor) {
 773                 *minor = plugin->info.version.minor;
 774         }
 775
 776         if (patch) {
 777                 *patch = plugin->info.version.patch;
 778         }
 779
 780         if (extra) {
 781                 *extra = plugin->info.version.extra->str;
 782         }
 783
 784 end:
 785         return avail;
 786 }
 787
 788 BT_EXPORT
 789 uint64_t bt_plugin_get_source_component_class_count(const struct bt_plugin *plugin)
 790 {
 791         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 792         return (uint64_t) plugin->src_comp_classes->len;
 793 }
 794
 795 BT_EXPORT
 796 uint64_t bt_plugin_get_filter_component_class_count(const struct bt_plugin *plugin)
 797 {
 798         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 799         return (uint64_t) plugin->flt_comp_classes->len;
 800 }
 801
 802 BT_EXPORT
 803 uint64_t bt_plugin_get_sink_component_class_count(const struct bt_plugin *plugin)
 804 {
 805         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 806         return (uint64_t) plugin->sink_comp_classes->len;
 807 }
 808
 809 static inline
 810 struct bt_component_class *borrow_component_class_by_index(
 811                 const struct bt_plugin *plugin, GPtrArray *comp_classes,
 812                 uint64_t index)
 813 {
 814         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 815         BT_ASSERT_PRE_DEV_VALID_INDEX(index, comp_classes->len);
 816         return g_ptr_array_index(comp_classes, index);
 817 }
 818
 819 BT_EXPORT
 820 const struct bt_component_class_source *
 821 bt_plugin_borrow_source_component_class_by_index_const(
 822                 const struct bt_plugin *plugin, uint64_t index)
 823 {
 824         return (const void *) borrow_component_class_by_index(plugin,
 825                 plugin->src_comp_classes, index);
 826 }
 827
 828 BT_EXPORT
 829 const struct bt_component_class_filter *
 830 bt_plugin_borrow_filter_component_class_by_index_const(
 831                 const struct bt_plugin *plugin, uint64_t index)
 832 {
 833         return (const void *) borrow_component_class_by_index(plugin,
 834                 plugin->flt_comp_classes, index);
 835 }
 836
 837 BT_EXPORT
 838 const struct bt_component_class_sink *
 839 bt_plugin_borrow_sink_component_class_by_index_const(
 840                 const struct bt_plugin *plugin, uint64_t index)
 841 {
 842         return (const void *) borrow_component_class_by_index(plugin,
 843                 plugin->sink_comp_classes, index);
 844 }
 845
 846 static inline
 847 struct bt_component_class *borrow_component_class_by_name(
 848                 const struct bt_plugin *plugin, GPtrArray *comp_classes,
 849                 const char *name)
 850 {
 851         struct bt_component_class *comp_class = NULL;
 852         size_t i;
 853
 854         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 855         BT_ASSERT_PRE_DEV_NAME_NON_NULL(name);
 856
 857         for (i = 0; i < comp_classes->len; i++) {
 858                 struct bt_component_class *comp_class_candidate =
 859                         g_ptr_array_index(comp_classes, i);
 860                 const char *comp_class_cand_name =
 861                         bt_component_class_get_name(comp_class_candidate);
 862
 863                 BT_ASSERT_DBG(comp_class_cand_name);
 864
 865                 if (strcmp(name, comp_class_cand_name) == 0) {
 866                         comp_class = comp_class_candidate;
 867                         break;
 868                 }
 869         }
 870
 871         return comp_class;
 872 }
 873
 874 BT_EXPORT
 875 const struct bt_component_class_source *
 876 bt_plugin_borrow_source_component_class_by_name_const(
 877                 const struct bt_plugin *plugin, const char *name)
 878 {
 879         return (const void *) borrow_component_class_by_name(plugin,
 880                 plugin->src_comp_classes, name);
 881 }
 882
 883 BT_EXPORT
 884 const struct bt_component_class_filter *
 885 bt_plugin_borrow_filter_component_class_by_name_const(
 886                 const struct bt_plugin *plugin, const char *name)
 887 {
 888         return (const void *) borrow_component_class_by_name(plugin,
 889                 plugin->flt_comp_classes, name);
 890 }
 891
 892 BT_EXPORT
 893 const struct bt_component_class_sink *
 894 bt_plugin_borrow_sink_component_class_by_name_const(
 895                 const struct bt_plugin *plugin, const char *name)
 896 {
 897         return (const void *) borrow_component_class_by_name(plugin,
 898                 plugin->sink_comp_classes, name);
 899 }
 900
 901 BT_EXPORT
 902 void bt_plugin_get_ref(const struct bt_plugin *plugin)
 903 {
 904         bt_object_get_ref(plugin);
 905 }
 906
 907 BT_EXPORT
 908 void bt_plugin_put_ref(const struct bt_plugin *plugin)
 909 {
 910         bt_object_put_ref(plugin);
 911 }
 912
 913 BT_EXPORT
 914 void bt_plugin_set_get_ref(const struct bt_plugin_set *plugin_set)
 915 {
 916         bt_object_get_ref(plugin_set);
 917 }
 918
 919 BT_EXPORT
 920 void bt_plugin_set_put_ref(const struct bt_plugin_set *plugin_set)
 921 {
 922         bt_object_put_ref(plugin_set);
 923 }