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