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 uint64_t bt_plugin_set_get_plugin_count(const struct bt_plugin_set *plugin_set)
 157 {
 158         BT_ASSERT_PRE_DEV_PLUGIN_SET_NON_NULL(plugin_set);
 159         return (uint64_t) plugin_set->plugins->len;
 160 }
 161
 162 const struct bt_plugin *bt_plugin_set_borrow_plugin_by_index_const(
 163                 const struct bt_plugin_set *plugin_set, uint64_t index)
 164 {
 165         BT_ASSERT_PRE_DEV_PLUGIN_SET_NON_NULL(plugin_set);
 166         BT_ASSERT_PRE_DEV_VALID_INDEX(index, plugin_set->plugins->len);
 167         return g_ptr_array_index(plugin_set->plugins, index);
 168 }
 169
 170 enum bt_plugin_find_all_from_static_status bt_plugin_find_all_from_static(
 171                 bt_bool fail_on_load_error,
 172                 const struct bt_plugin_set **plugin_set_out)
 173 {
 174         BT_ASSERT_PRE_NO_ERROR();
 175
 176         /* bt_plugin_so_create_all_from_static() logs errors */
 177         return bt_plugin_so_create_all_from_static(fail_on_load_error,
 178                 (void *) plugin_set_out);
 179 }
 180
 181 enum bt_plugin_find_all_from_file_status bt_plugin_find_all_from_file(
 182                 const char *path, bt_bool fail_on_load_error,
 183                 const struct bt_plugin_set **plugin_set_out)
 184 {
 185         enum bt_plugin_find_all_from_file_status status;
 186
 187         BT_ASSERT_PRE_NO_ERROR();
 188         BT_ASSERT_PRE_NON_NULL("path", path, "Path");
 189         BT_ASSERT_PRE_PLUGIN_SET_OUT_NON_NULL(path);
 190         BT_LOGI("Creating plugins from file: path=\"%s\"", path);
 191
 192         /* Try shared object plugins */
 193         status = bt_plugin_so_create_all_from_file(path, fail_on_load_error,
 194                 (void *) plugin_set_out);
 195         if (status == BT_FUNC_STATUS_OK) {
 196                 BT_ASSERT(*plugin_set_out);
 197                 BT_ASSERT((*plugin_set_out)->plugins->len > 0);
 198                 goto end;
 199         } else if (status < 0) {
 200                 BT_ASSERT(!*plugin_set_out);
 201                 goto end;
 202         }
 203
 204         BT_ASSERT(status == BT_FUNC_STATUS_NOT_FOUND);
 205         BT_ASSERT(!*plugin_set_out);
 206
 207         /* Try Python plugins if support is available */
 208         status = init_python_plugin_provider();
 209         if (status < 0) {
 210                 /* init_python_plugin_provider() logs errors */
 211                 goto end;
 212         }
 213
 214         BT_ASSERT(status == BT_FUNC_STATUS_OK);
 215         status = BT_FUNC_STATUS_NOT_FOUND;
 216
 217         if (bt_plugin_python_create_all_from_file_sym) {
 218                 /* Python plugin provider exists */
 219                 status = bt_plugin_python_create_all_from_file_sym(path,
 220                         fail_on_load_error, (void *) plugin_set_out);
 221                 if (status == BT_FUNC_STATUS_OK) {
 222                         BT_ASSERT(*plugin_set_out);
 223                         BT_ASSERT((*plugin_set_out)->plugins->len > 0);
 224                         goto end;
 225                 } else if (status < 0) {
 226                         /*
 227                          * bt_plugin_python_create_all_from_file_sym()
 228                          * handles `fail_on_load_error` itself, so this
 229                          * is a "real" error.
 230                          */
 231                         BT_ASSERT(!*plugin_set_out);
 232                         goto end;
 233                 }
 234
 235                 BT_ASSERT(status == BT_FUNC_STATUS_NOT_FOUND);
 236                 BT_ASSERT(!*plugin_set_out);
 237         }
 238
 239 end:
 240         if (status == BT_FUNC_STATUS_OK) {
 241                 BT_LOGI("Created %u plugins from file: "
 242                         "path=\"%s\", count=%u, plugin-set-addr=%p",
 243                         (*plugin_set_out)->plugins->len, path,
 244                         (*plugin_set_out)->plugins->len,
 245                         *plugin_set_out);
 246         } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 247                 BT_LOGI("Found no plugins in file: path=\"%s\"", path);
 248         }
 249
 250         return status;
 251 }
 252
 253 static
 254 void destroy_gstring(void *data)
 255 {
 256         g_string_free(data, TRUE);
 257 }
 258
 259 enum bt_plugin_find_all_status bt_plugin_find_all(bt_bool find_in_std_env_var,
 260                 bt_bool find_in_user_dir, bt_bool find_in_sys_dir,
 261                 bt_bool find_in_static, bt_bool fail_on_load_error,
 262                 const struct bt_plugin_set **plugin_set_out)
 263 {
 264         char *home_plugin_dir = NULL;
 265         const struct bt_plugin_set *plugin_set = NULL;
 266         GPtrArray *dirs = NULL;
 267         int ret;
 268         int status = BT_FUNC_STATUS_OK;
 269         uint64_t dir_i, plugin_i;
 270
 271         BT_ASSERT_PRE_NO_ERROR();
 272         BT_ASSERT_PRE_PLUGIN_SET_OUT_NON_NULL(plugin_set_out);
 273         BT_LOGI("Finding all plugins in standard directories and built-in plugins: "
 274                 "find-in-std-env-var=%d, find-in-user-dir=%d, "
 275                 "find-in-sys-dir=%d, find-in-static=%d",
 276                 find_in_std_env_var, find_in_user_dir, find_in_sys_dir,
 277                 find_in_static);
 278         dirs = g_ptr_array_new_with_free_func((GDestroyNotify) destroy_gstring);
 279         if (!dirs) {
 280                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GPtrArray.");
 281                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 282                 goto end;
 283         }
 284
 285         *plugin_set_out = bt_plugin_set_create();
 286         if (!*plugin_set_out) {
 287                 BT_LIB_LOGE_APPEND_CAUSE("Cannot create empty plugin set.");
 288                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 289                 goto end;
 290         }
 291
 292         /*
 293          * Search order is:
 294          *
 295          * 1. `BABELTRACE_PLUGIN_PATH` environment variable
 296          *    (colon-separated list of directories)
 297          * 2. `~/.local/lib/babeltrace2/plugins`
 298          * 3. Default system directory for Babeltrace plugins, usually
 299          *    `/usr/lib/babeltrace2/plugins` or
 300          *    `/usr/local/lib/babeltrace2/plugins` if installed locally
 301          * 4. Built-in plugins (static)
 302          *
 303          * Directories are searched non-recursively.
 304          */
 305         if (find_in_std_env_var) {
 306                 const char *envvar = getenv("BABELTRACE_PLUGIN_PATH");
 307
 308                 if (envvar) {
 309                         ret = bt_common_append_plugin_path_dirs(envvar, dirs);
 310                         if (ret) {
 311                                 BT_LIB_LOGE_APPEND_CAUSE(
 312                                         "Failed to append plugin path to array of directories.");
 313                                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 314                                 goto end;
 315                         }
 316                 }
 317         }
 318
 319         if (find_in_user_dir) {
 320                 home_plugin_dir = bt_common_get_home_plugin_path(
 321                         BT_LOG_OUTPUT_LEVEL);
 322                 if (home_plugin_dir) {
 323                         GString *home_plugin_dir_str = g_string_new(
 324                                 home_plugin_dir);
 325
 326                         if (!home_plugin_dir_str) {
 327                                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GString.");
 328                                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 329                                 goto end;
 330                         }
 331
 332                         g_ptr_array_add(dirs, home_plugin_dir_str);
 333                 }
 334         }
 335
 336         if (find_in_sys_dir) {
 337                 const char *system_plugin_dir =
 338                         bt_common_get_system_plugin_path();
 339
 340                 if (system_plugin_dir) {
 341                         GString *system_plugin_dir_str =
 342                                 g_string_new(system_plugin_dir);
 343
 344                         if (!system_plugin_dir_str) {
 345                                 BT_LIB_LOGE_APPEND_CAUSE("Failed to allocate a GString.");
 346                                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 347                                 goto end;
 348                         }
 349
 350                         g_ptr_array_add(dirs, system_plugin_dir_str);
 351                 }
 352         }
 353
 354         for (dir_i = 0; dir_i < dirs->len; dir_i++) {
 355                 GString *dir = dirs->pdata[dir_i];
 356
 357                 BT_OBJECT_PUT_REF_AND_RESET(plugin_set);
 358
 359                 /*
 360                  * Skip this if the directory does not exist because
 361                  * bt_plugin_find_all_from_dir() would log a warning.
 362                  */
 363                 if (!g_file_test(dir->str, G_FILE_TEST_IS_DIR)) {
 364                         BT_LOGI("Skipping nonexistent directory path: "
 365                                 "path=\"%s\"", dir->str);
 366                         continue;
 367                 }
 368
 369                 /* bt_plugin_find_all_from_dir() logs details/errors */
 370                 status = bt_plugin_find_all_from_dir(dir->str, BT_FALSE,
 371                         fail_on_load_error, &plugin_set);
 372                 if (status < 0) {
 373                         BT_ASSERT(!plugin_set);
 374                         goto end;
 375                 } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 376                         BT_ASSERT(!plugin_set);
 377                         BT_LOGI("No plugins found in directory: path=\"%s\"",
 378                                 dir->str);
 379                         continue;
 380                 }
 381
 382                 BT_ASSERT(status == BT_FUNC_STATUS_OK);
 383                 BT_ASSERT(plugin_set);
 384                 BT_LOGI("Found plugins in directory: path=\"%s\", count=%u",
 385                         dir->str, plugin_set->plugins->len);
 386
 387                 for (plugin_i = 0; plugin_i < plugin_set->plugins->len;
 388                                 plugin_i++) {
 389                         bt_plugin_set_add_plugin((void *) *plugin_set_out,
 390                                 plugin_set->plugins->pdata[plugin_i]);
 391                 }
 392         }
 393
 394         if (find_in_static) {
 395                 BT_OBJECT_PUT_REF_AND_RESET(plugin_set);
 396                 status = bt_plugin_find_all_from_static(fail_on_load_error,
 397                         &plugin_set);
 398                 if (status < 0) {
 399                         BT_ASSERT(!plugin_set);
 400                         goto end;
 401                 } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 402                         BT_ASSERT(!plugin_set);
 403                         BT_LOGI_STR("No plugins found in built-in plugins.");
 404                         goto end;
 405                 }
 406
 407                 BT_ASSERT(status == BT_FUNC_STATUS_OK);
 408                 BT_ASSERT(plugin_set);
 409                 BT_LOGI("Found built-in plugins: count=%u",
 410                         plugin_set->plugins->len);
 411
 412                 for (plugin_i = 0; plugin_i < plugin_set->plugins->len;
 413                                 plugin_i++) {
 414                         bt_plugin_set_add_plugin((void *) *plugin_set_out,
 415                                 plugin_set->plugins->pdata[plugin_i]);
 416                 }
 417         }
 418
 419 end:
 420         free(home_plugin_dir);
 421         bt_object_put_ref(plugin_set);
 422
 423         if (dirs) {
 424                 g_ptr_array_free(dirs, TRUE);
 425         }
 426
 427         if (status < 0) {
 428                 BT_OBJECT_PUT_REF_AND_RESET(*plugin_set_out);
 429         } else {
 430                 BT_ASSERT(*plugin_set_out);
 431
 432                 if ((*plugin_set_out)->plugins->len > 0) {
 433                         BT_LOGI("Found plugins in standard directories and built-in plugins: "
 434                                 "count=%u", (*plugin_set_out)->plugins->len);
 435                         status = BT_FUNC_STATUS_OK;
 436                 } else {
 437                         BT_LOGI_STR("No plugins found in standard directories and built-in plugins.");
 438                         status = BT_FUNC_STATUS_NOT_FOUND;
 439                         BT_OBJECT_PUT_REF_AND_RESET(*plugin_set_out);
 440                 }
 441         }
 442
 443         return status;
 444 }
 445
 446 enum bt_plugin_find_status bt_plugin_find(const char *plugin_name,
 447                 bt_bool find_in_std_env_var, bt_bool find_in_user_dir,
 448                 bt_bool find_in_sys_dir, bt_bool find_in_static,
 449                 bt_bool fail_on_load_error, const struct bt_plugin **plugin_out)
 450 {
 451         enum bt_plugin_find_status status;
 452         const struct bt_plugin_set *plugin_set = NULL;
 453         uint64_t i;
 454
 455         BT_ASSERT_PRE_NO_ERROR();
 456         BT_ASSERT_PRE_NAME_NON_NULL(plugin_name);
 457         BT_ASSERT_PRE_PLUGIN_OUT_NON_NULL(plugin_out);
 458         BT_LOGI("Finding named plugin in standard directories and built-in plugins: "
 459                 "name=\"%s\", find-in-std-env-var=%d, find-in-user-dir=%d, "
 460                 "find-in-sys-dir=%d, find-in-static=%d",
 461                 plugin_name, find_in_std_env_var, find_in_user_dir,
 462                 find_in_sys_dir, find_in_static);
 463         status = (enum bt_plugin_find_status) bt_plugin_find_all(find_in_std_env_var, find_in_user_dir,
 464                 find_in_sys_dir, find_in_static, fail_on_load_error,
 465                 &plugin_set);
 466         if (status != BT_FUNC_STATUS_OK) {
 467                 BT_ASSERT(!plugin_set);
 468                 goto end;
 469         }
 470
 471         BT_ASSERT(plugin_set);
 472
 473         for (i = 0; i < plugin_set->plugins->len; i++) {
 474                 const struct bt_plugin *plugin = plugin_set->plugins->pdata[i];
 475
 476                 if (strcmp(plugin->info.name->str, plugin_name) == 0) {
 477                         *plugin_out = plugin;
 478                         bt_object_get_ref_no_null_check(*plugin_out);
 479                         goto end;
 480                 }
 481         }
 482
 483         status = BT_FUNC_STATUS_NOT_FOUND;
 484
 485 end:
 486         if (status == BT_FUNC_STATUS_OK) {
 487                 BT_ASSERT(*plugin_out);
 488                 BT_LIB_LOGI("Found plugin in standard directories and built-in plugins: "
 489                         "%!+l", *plugin_out);
 490         } else if (status == BT_FUNC_STATUS_NOT_FOUND) {
 491                 BT_LOGI("No plugin found in standard directories and built-in plugins: "
 492                         "name=\"%s\"", plugin_name);
 493         }
 494
 495         bt_plugin_set_put_ref(plugin_set);
 496
 497         return status;
 498 }
 499
 500 static struct {
 501         pthread_mutex_t lock;
 502         struct bt_plugin_set *plugin_set;
 503         bool recurse;
 504         bool fail_on_load_error;
 505         int status;
 506 } append_all_from_dir_info = {
 507         .lock = PTHREAD_MUTEX_INITIALIZER
 508 };
 509
 510 static
 511 int nftw_append_all_from_dir(const char *file,
 512                 const struct stat *sb, int flag, struct FTW *s)
 513 {
 514         int ret = 0;
 515         const char *name = file + s->base;
 516
 517         /* Check for recursion */
 518         if (!append_all_from_dir_info.recurse && s->level > 1) {
 519                 goto end;
 520         }
 521
 522         switch (flag) {
 523         case FTW_F:
 524         {
 525                 const struct bt_plugin_set *plugins_from_file = NULL;
 526
 527                 if (name[0] == '.') {
 528                         /* Skip hidden files */
 529                         BT_LOGI("Skipping hidden file: path=\"%s\"", file);
 530                         goto end;
 531                 }
 532
 533                 append_all_from_dir_info.status =
 534                         bt_plugin_find_all_from_file(file,
 535                                 append_all_from_dir_info.fail_on_load_error,
 536                                 &plugins_from_file);
 537                 if (append_all_from_dir_info.status == BT_FUNC_STATUS_OK) {
 538                         size_t j;
 539
 540                         BT_ASSERT(plugins_from_file);
 541
 542                         for (j = 0; j < plugins_from_file->plugins->len; j++) {
 543                                 struct bt_plugin *plugin =
 544                                         g_ptr_array_index(plugins_from_file->plugins, j);
 545
 546                                 BT_LIB_LOGI("Adding plugin to plugin set: "
 547                                         "plugin-path=\"%s\", %![plugin-]+l",
 548                                         file, plugin);
 549                                 bt_plugin_set_add_plugin(
 550                                         append_all_from_dir_info.plugin_set,
 551                                         plugin);
 552                         }
 553
 554                         bt_object_put_ref(plugins_from_file);
 555                         goto end;
 556                 } else if (append_all_from_dir_info.status < 0) {
 557                         /* bt_plugin_find_all_from_file() logs errors */
 558                         BT_ASSERT(!plugins_from_file);
 559                         ret = -1;
 560                         goto end;
 561                 }
 562
 563                 /*
 564                  * Not found in this file: this is no an error; continue
 565                  * walking the directories.
 566                  */
 567                 BT_ASSERT(!plugins_from_file);
 568                 BT_ASSERT(append_all_from_dir_info.status ==
 569                         BT_FUNC_STATUS_NOT_FOUND);
 570                 break;
 571         }
 572         case FTW_DNR:
 573                 /* Continue to next file / directory. */
 574                 BT_LOGI("Cannot enter directory: continuing: path=\"%s\"", file);
 575                 break;
 576         case FTW_NS:
 577                 /* Continue to next file / directory. */
 578                 BT_LOGI("Cannot get file information: continuing: path=\"%s\"", file);
 579                 break;
 580         }
 581
 582 end:
 583         return ret;
 584 }
 585
 586 static
 587 int bt_plugin_create_append_all_from_dir(struct bt_plugin_set *plugin_set,
 588                 const char *path, bt_bool recurse, bt_bool fail_on_load_error)
 589 {
 590         int nftw_flags = FTW_PHYS;
 591         int ret;
 592         int status;
 593         struct stat sb;
 594
 595         BT_ASSERT(plugin_set);
 596         BT_ASSERT(path);
 597         BT_ASSERT(strlen(path) < PATH_MAX);
 598
 599         /*
 600          * Make sure that path exists and is accessible.
 601          * This is necessary since Cygwin implementation of nftw() is not POSIX
 602          * compliant. Cygwin nftw() implementation does not fail on non-existent
 603          * path with ENOENT. Instead, it flags the directory as FTW_NS. FTW_NS during
 604          * nftw_append_all_from_dir is not treated as an error since we are
 605          * traversing the tree for plugin discovery.
 606          */
 607         if (stat(path, &sb)) {
 608                 BT_LOGW_ERRNO("Cannot open directory",
 609                         ": path=\"%s\", recurse=%d",
 610                         path, recurse);
 611                 (void) BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_UNKNOWN(
 612                         BT_LIB_LOG_LIBBABELTRACE2_NAME,
 613                         "Cannot open directory: path=\"%s\", recurse=%d",
 614                         path, recurse);
 615                 status = BT_FUNC_STATUS_ERROR;
 616                 goto end;
 617         }
 618
 619         pthread_mutex_lock(&append_all_from_dir_info.lock);
 620         append_all_from_dir_info.plugin_set = plugin_set;
 621         append_all_from_dir_info.recurse = recurse;
 622         append_all_from_dir_info.status = BT_FUNC_STATUS_OK;
 623         append_all_from_dir_info.fail_on_load_error = fail_on_load_error;
 624         ret = nftw(path, nftw_append_all_from_dir,
 625                 APPEND_ALL_FROM_DIR_NFDOPEN_MAX, nftw_flags);
 626         append_all_from_dir_info.plugin_set = NULL;
 627         status = append_all_from_dir_info.status;
 628         pthread_mutex_unlock(&append_all_from_dir_info.lock);
 629         if (ret) {
 630                 BT_LIB_LOGW_APPEND_CAUSE("Failed to walk directory",
 631                         ": path=\"%s\", recurse=%d",
 632                         path, recurse);
 633                 status = BT_FUNC_STATUS_ERROR;
 634                 goto end;
 635         }
 636
 637         if (status == BT_FUNC_STATUS_NOT_FOUND) {
 638                 /*
 639                  * We're just appending in this function; even if
 640                  * nothing was found, it's still okay from the caller's
 641                  * perspective.
 642                  */
 643                 status = BT_FUNC_STATUS_OK;
 644         }
 645
 646 end:
 647         return status;
 648 }
 649
 650 enum bt_plugin_find_all_from_dir_status bt_plugin_find_all_from_dir(
 651                 const char *path, bt_bool recurse, bt_bool fail_on_load_error,
 652                 const struct bt_plugin_set **plugin_set_out)
 653 {
 654         enum bt_plugin_find_all_from_dir_status status =
 655                 BT_FUNC_STATUS_OK;
 656
 657         BT_ASSERT_PRE_NO_ERROR();
 658         BT_ASSERT_PRE_PLUGIN_SET_OUT_NON_NULL(plugin_set_out);
 659         BT_LOGI("Creating all plugins in directory: path=\"%s\", recurse=%d",
 660                 path, recurse);
 661         *plugin_set_out = bt_plugin_set_create();
 662         if (!*plugin_set_out) {
 663                 BT_LIB_LOGE_APPEND_CAUSE("Cannot create empty plugin set.");
 664                 status = BT_FUNC_STATUS_MEMORY_ERROR;
 665                 goto error;
 666         }
 667
 668         /*
 669          * Append found plugins to array (never returns
 670          * `BT_FUNC_STATUS_NOT_FOUND`)
 671          */
 672         status = bt_plugin_create_append_all_from_dir((void *) *plugin_set_out,
 673                 path, recurse, fail_on_load_error);
 674         if (status < 0) {
 675                 /*
 676                  * bt_plugin_create_append_all_from_dir() handles
 677                  * `fail_on_load_error`, so this is a "real" error.
 678                  */
 679                 BT_LIB_LOGE_APPEND_CAUSE(
 680                         "Cannot append plugins found in directory: "
 681                         "path=\"%s\", status=%s",
 682                         path, bt_common_func_status_string(status));
 683                 goto error;
 684         }
 685
 686         BT_ASSERT(status == BT_FUNC_STATUS_OK);
 687
 688         if ((*plugin_set_out)->plugins->len == 0) {
 689                 /* Nothing was appended: not found */
 690                 BT_LOGI("No plugins found in directory: path=\"%s\"", path);
 691                 status = BT_FUNC_STATUS_NOT_FOUND;
 692                 goto error;
 693         }
 694
 695         BT_LOGI("Created %u plugins from directory: count=%u, path=\"%s\"",
 696                 (*plugin_set_out)->plugins->len,
 697                 (*plugin_set_out)->plugins->len, path);
 698         goto end;
 699
 700 error:
 701         BT_ASSERT(status != BT_FUNC_STATUS_OK);
 702         BT_OBJECT_PUT_REF_AND_RESET(*plugin_set_out);
 703
 704 end:
 705         return status;
 706 }
 707
 708 const char *bt_plugin_get_name(const struct bt_plugin *plugin)
 709 {
 710         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 711         return plugin->info.name_set ? plugin->info.name->str : NULL;
 712 }
 713
 714 const char *bt_plugin_get_author(const struct bt_plugin *plugin)
 715 {
 716         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 717         return plugin->info.author_set ? plugin->info.author->str : NULL;
 718 }
 719
 720 const char *bt_plugin_get_license(const struct bt_plugin *plugin)
 721 {
 722         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 723         return plugin->info.license_set ? plugin->info.license->str : NULL;
 724 }
 725
 726 const char *bt_plugin_get_path(const struct bt_plugin *plugin)
 727 {
 728         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 729         return plugin->info.path_set ? plugin->info.path->str : NULL;
 730 }
 731
 732 const char *bt_plugin_get_description(const struct bt_plugin *plugin)
 733 {
 734         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 735         return plugin->info.description_set ?
 736                 plugin->info.description->str : NULL;
 737 }
 738
 739 enum bt_property_availability bt_plugin_get_version(const struct bt_plugin *plugin,
 740                 unsigned int *major, unsigned int *minor, unsigned int *patch,
 741                 const char **extra)
 742 {
 743         enum bt_property_availability avail =
 744                 BT_PROPERTY_AVAILABILITY_AVAILABLE;
 745
 746         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 747
 748         if (!plugin->info.version_set) {
 749                 BT_LIB_LOGD("Plugin's version is not set: %!+l", plugin);
 750                 avail = BT_PROPERTY_AVAILABILITY_NOT_AVAILABLE;
 751                 goto end;
 752         }
 753
 754         if (major) {
 755                 *major = plugin->info.version.major;
 756         }
 757
 758         if (minor) {
 759                 *minor = plugin->info.version.minor;
 760         }
 761
 762         if (patch) {
 763                 *patch = plugin->info.version.patch;
 764         }
 765
 766         if (extra) {
 767                 *extra = plugin->info.version.extra->str;
 768         }
 769
 770 end:
 771         return avail;
 772 }
 773
 774 uint64_t bt_plugin_get_source_component_class_count(const struct bt_plugin *plugin)
 775 {
 776         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 777         return (uint64_t) plugin->src_comp_classes->len;
 778 }
 779
 780 uint64_t bt_plugin_get_filter_component_class_count(const struct bt_plugin *plugin)
 781 {
 782         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 783         return (uint64_t) plugin->flt_comp_classes->len;
 784 }
 785
 786 uint64_t bt_plugin_get_sink_component_class_count(const struct bt_plugin *plugin)
 787 {
 788         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 789         return (uint64_t) plugin->sink_comp_classes->len;
 790 }
 791
 792 static inline
 793 struct bt_component_class *borrow_component_class_by_index(
 794                 const struct bt_plugin *plugin, GPtrArray *comp_classes,
 795                 uint64_t index)
 796 {
 797         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 798         BT_ASSERT_PRE_DEV_VALID_INDEX(index, comp_classes->len);
 799         return g_ptr_array_index(comp_classes, index);
 800 }
 801
 802 const struct bt_component_class_source *
 803 bt_plugin_borrow_source_component_class_by_index_const(
 804                 const struct bt_plugin *plugin, uint64_t index)
 805 {
 806         return (const void *) borrow_component_class_by_index(plugin,
 807                 plugin->src_comp_classes, index);
 808 }
 809
 810 const struct bt_component_class_filter *
 811 bt_plugin_borrow_filter_component_class_by_index_const(
 812                 const struct bt_plugin *plugin, uint64_t index)
 813 {
 814         return (const void *) borrow_component_class_by_index(plugin,
 815                 plugin->flt_comp_classes, index);
 816 }
 817
 818 const struct bt_component_class_sink *
 819 bt_plugin_borrow_sink_component_class_by_index_const(
 820                 const struct bt_plugin *plugin, uint64_t index)
 821 {
 822         return (const void *) borrow_component_class_by_index(plugin,
 823                 plugin->sink_comp_classes, index);
 824 }
 825
 826 static inline
 827 struct bt_component_class *borrow_component_class_by_name(
 828                 const struct bt_plugin *plugin, GPtrArray *comp_classes,
 829                 const char *name)
 830 {
 831         struct bt_component_class *comp_class = NULL;
 832         size_t i;
 833
 834         BT_ASSERT_PRE_DEV_PLUGIN_NON_NULL(plugin);
 835         BT_ASSERT_PRE_DEV_NAME_NON_NULL(name);
 836
 837         for (i = 0; i < comp_classes->len; i++) {
 838                 struct bt_component_class *comp_class_candidate =
 839                         g_ptr_array_index(comp_classes, i);
 840                 const char *comp_class_cand_name =
 841                         bt_component_class_get_name(comp_class_candidate);
 842
 843                 BT_ASSERT_DBG(comp_class_cand_name);
 844
 845                 if (strcmp(name, comp_class_cand_name) == 0) {
 846                         comp_class = comp_class_candidate;
 847                         break;
 848                 }
 849         }
 850
 851         return comp_class;
 852 }
 853
 854 const struct bt_component_class_source *
 855 bt_plugin_borrow_source_component_class_by_name_const(
 856                 const struct bt_plugin *plugin, const char *name)
 857 {
 858         return (const void *) borrow_component_class_by_name(plugin,
 859                 plugin->src_comp_classes, name);
 860 }
 861
 862 const struct bt_component_class_filter *
 863 bt_plugin_borrow_filter_component_class_by_name_const(
 864                 const struct bt_plugin *plugin, const char *name)
 865 {
 866         return (const void *) borrow_component_class_by_name(plugin,
 867                 plugin->flt_comp_classes, name);
 868 }
 869
 870 const struct bt_component_class_sink *
 871 bt_plugin_borrow_sink_component_class_by_name_const(
 872                 const struct bt_plugin *plugin, const char *name)
 873 {
 874         return (const void *) borrow_component_class_by_name(plugin,
 875                 plugin->sink_comp_classes, name);
 876 }
 877
 878 void bt_plugin_get_ref(const struct bt_plugin *plugin)
 879 {
 880         bt_object_get_ref(plugin);
 881 }
 882
 883 void bt_plugin_put_ref(const struct bt_plugin *plugin)
 884 {
 885         bt_object_put_ref(plugin);
 886 }
 887
 888 void bt_plugin_set_get_ref(const struct bt_plugin_set *plugin_set)
 889 {
 890         bt_object_get_ref(plugin_set);
 891 }
 892
 893 void bt_plugin_set_put_ref(const struct bt_plugin_set *plugin_set)
 894 {
 895         bt_object_put_ref(plugin_set);
 896 }