| 1 | /* |
| 2 | * component-factory.c |
| 3 | * |
| 4 | * Babeltrace Plugin Component Factory |
| 5 | * |
| 6 | * Copyright 2015 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 7 | * |
| 8 | * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 9 | * |
| 10 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 11 | * of this software and associated documentation files (the "Software"), to deal |
| 12 | * in the Software without restriction, including without limitation the rights |
| 13 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 14 | * copies of the Software, and to permit persons to whom the Software is |
| 15 | * furnished to do so, subject to the following conditions: |
| 16 | * |
| 17 | * The above copyright notice and this permission notice shall be included in |
| 18 | * all copies or substantial portions of the Software. |
| 19 | * |
| 20 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 21 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 22 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 23 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 24 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 25 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 26 | * SOFTWARE. |
| 27 | */ |
| 28 | |
| 29 | #include <babeltrace/plugin/component-factory.h> |
| 30 | #include <babeltrace/plugin/component-factory-internal.h> |
| 31 | #include <babeltrace/plugin/component-class-internal.h> |
| 32 | #include <babeltrace/plugin/source-internal.h> |
| 33 | #include <babeltrace/plugin/sink-internal.h> |
| 34 | #include <babeltrace/babeltrace-internal.h> |
| 35 | #include <babeltrace/compiler.h> |
| 36 | #include <babeltrace/ref.h> |
| 37 | #include <unistd.h> |
| 38 | #include <stdlib.h> |
| 39 | #include <sys/stat.h> |
| 40 | #include <gmodule.h> |
| 41 | #include <stdbool.h> |
| 42 | #include <dirent.h> |
| 43 | |
| 44 | #define NATIVE_PLUGIN_SUFFIX ".so" |
| 45 | #define NATIVE_PLUGIN_SUFFIX_LEN sizeof(NATIVE_PLUGIN_SUFFIX) |
| 46 | #define LIBTOOL_PLUGIN_SUFFIX ".la" |
| 47 | #define LIBTOOL_PLUGIN_SUFFIX_LEN sizeof(LIBTOOL_PLUGIN_SUFFIX) |
| 48 | #define PLUGIN_SUFFIX_LEN max_t(size_t, sizeof(NATIVE_PLUGIN_SUFFIX), \ |
| 49 | sizeof(LIBTOOL_PLUGIN_SUFFIX)) |
| 50 | |
| 51 | /* Allocate dirent as recommended by READDIR(3), NOTES on readdir_r */ |
| 52 | static |
| 53 | struct dirent *alloc_dirent(const char *path) |
| 54 | { |
| 55 | size_t len; |
| 56 | long name_max; |
| 57 | struct dirent *entry; |
| 58 | |
| 59 | name_max = pathconf(path, _PC_NAME_MAX); |
| 60 | if (name_max == -1) { |
| 61 | name_max = PATH_MAX; |
| 62 | } |
| 63 | len = offsetof(struct dirent, d_name) + name_max + 1; |
| 64 | entry = zmalloc(len); |
| 65 | return entry; |
| 66 | } |
| 67 | |
| 68 | static |
| 69 | enum bt_component_factory_status |
| 70 | bt_component_factory_load_file(struct bt_component_factory *factory, |
| 71 | const char *path) |
| 72 | { |
| 73 | enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK; |
| 74 | enum bt_component_status component_status; |
| 75 | size_t path_len; |
| 76 | GModule *module; |
| 77 | struct bt_plugin *plugin; |
| 78 | bool is_libtool_wrapper = false, is_shared_object = false; |
| 79 | |
| 80 | if (!factory || !path) { |
| 81 | ret = BT_COMPONENT_FACTORY_STATUS_INVAL; |
| 82 | goto end; |
| 83 | } |
| 84 | |
| 85 | path_len = strlen(path); |
| 86 | if (path_len <= PLUGIN_SUFFIX_LEN) { |
| 87 | ret = BT_COMPONENT_FACTORY_STATUS_INVAL; |
| 88 | goto end; |
| 89 | } |
| 90 | |
| 91 | path_len++; |
| 92 | /* |
| 93 | * Check if the file ends with a known plugin file type suffix (i.e. .so |
| 94 | * or .la on Linux). |
| 95 | */ |
| 96 | is_libtool_wrapper = !strncmp(LIBTOOL_PLUGIN_SUFFIX, |
| 97 | path + path_len - LIBTOOL_PLUGIN_SUFFIX_LEN, |
| 98 | LIBTOOL_PLUGIN_SUFFIX_LEN); |
| 99 | is_shared_object = !strncmp(NATIVE_PLUGIN_SUFFIX, |
| 100 | path + path_len - NATIVE_PLUGIN_SUFFIX_LEN, |
| 101 | NATIVE_PLUGIN_SUFFIX_LEN); |
| 102 | if (!is_shared_object && !is_libtool_wrapper) { |
| 103 | /* Name indicates that this is not a plugin file. */ |
| 104 | ret = BT_COMPONENT_FACTORY_STATUS_INVAL; |
| 105 | goto end; |
| 106 | } |
| 107 | |
| 108 | module = g_module_open(path, 0); |
| 109 | if (!module) { |
| 110 | printf_verbose("Module open error: %s\n", g_module_error()); |
| 111 | ret = BT_COMPONENT_FACTORY_STATUS_ERROR; |
| 112 | goto end; |
| 113 | } |
| 114 | |
| 115 | /* Load plugin and make sure it defines the required entry points */ |
| 116 | plugin = bt_plugin_create(module, path); |
| 117 | if (!plugin) { |
| 118 | ret = BT_COMPONENT_FACTORY_STATUS_INVAL_PLUGIN; |
| 119 | if (!g_module_close(module)) { |
| 120 | printf_error("Module close error: %s", |
| 121 | g_module_error()); |
| 122 | } |
| 123 | goto end; |
| 124 | } |
| 125 | |
| 126 | BT_MOVE(factory->current_plugin, plugin); |
| 127 | component_status = bt_plugin_register_component_classes( |
| 128 | factory->current_plugin, factory); |
| 129 | BT_PUT(factory->current_plugin); |
| 130 | if (component_status != BT_COMPONENT_STATUS_OK) { |
| 131 | switch (component_status) { |
| 132 | case BT_COMPONENT_STATUS_NOMEM: |
| 133 | ret = BT_COMPONENT_FACTORY_STATUS_NOMEM; |
| 134 | break; |
| 135 | default: |
| 136 | ret = BT_COMPONENT_FACTORY_STATUS_ERROR; |
| 137 | break; |
| 138 | } |
| 139 | |
| 140 | goto end; |
| 141 | } |
| 142 | end: |
| 143 | return ret; |
| 144 | } |
| 145 | |
| 146 | static |
| 147 | enum bt_component_factory_status |
| 148 | bt_component_factory_load_dir(struct bt_component_factory *factory, |
| 149 | const char *path, bool recurse) |
| 150 | { |
| 151 | DIR *directory = NULL; |
| 152 | struct dirent *entry = NULL, *result = NULL; |
| 153 | char *file_path = NULL; |
| 154 | size_t path_len = strlen(path); |
| 155 | enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK; |
| 156 | |
| 157 | if (path_len >= PATH_MAX) { |
| 158 | ret = BT_COMPONENT_FACTORY_STATUS_INVAL; |
| 159 | goto end; |
| 160 | } |
| 161 | |
| 162 | entry = alloc_dirent(path); |
| 163 | if (!entry) { |
| 164 | ret = BT_COMPONENT_FACTORY_STATUS_NOMEM; |
| 165 | goto end; |
| 166 | } |
| 167 | |
| 168 | file_path = zmalloc(PATH_MAX); |
| 169 | if (!file_path) { |
| 170 | ret = BT_COMPONENT_FACTORY_STATUS_NOMEM; |
| 171 | goto end; |
| 172 | } |
| 173 | |
| 174 | strncpy(file_path, path, path_len); |
| 175 | /* Append a trailing '/' to the path */ |
| 176 | if (file_path[path_len - 1] != '/') { |
| 177 | file_path[path_len++] = '/'; |
| 178 | } |
| 179 | |
| 180 | directory = opendir(file_path); |
| 181 | if (!directory) { |
| 182 | perror("Failed to open plug-in directory"); |
| 183 | ret = BT_COMPONENT_FACTORY_STATUS_ERROR; |
| 184 | goto end; |
| 185 | } |
| 186 | |
| 187 | /* Recursively walk directory */ |
| 188 | while (!readdir_r(directory, entry, &result) && result) { |
| 189 | struct stat st; |
| 190 | int stat_ret; |
| 191 | size_t file_name_len; |
| 192 | |
| 193 | if (result->d_name[0] == '.') { |
| 194 | /* Skip hidden files, . and .. */ |
| 195 | continue; |
| 196 | } |
| 197 | |
| 198 | file_name_len = strlen(result->d_name); |
| 199 | |
| 200 | if (path_len + file_name_len >= PATH_MAX) { |
| 201 | continue; |
| 202 | } |
| 203 | |
| 204 | strncpy(file_path + path_len, result->d_name, file_name_len); |
| 205 | file_path[path_len + file_name_len] = '\0'; |
| 206 | |
| 207 | stat_ret = stat(file_path, &st); |
| 208 | if (stat_ret < 0) { |
| 209 | /* Continue to next file / directory. */ |
| 210 | printf_perror("Failed to stat() plugin file"); |
| 211 | continue; |
| 212 | } |
| 213 | |
| 214 | if (S_ISDIR(st.st_mode) && recurse) { |
| 215 | ret = bt_component_factory_load_dir(factory, |
| 216 | file_path, true); |
| 217 | if (ret != BT_COMPONENT_FACTORY_STATUS_OK) { |
| 218 | goto end; |
| 219 | } |
| 220 | } else if (S_ISREG(st.st_mode)) { |
| 221 | bt_component_factory_load_file(factory, file_path); |
| 222 | } |
| 223 | } |
| 224 | end: |
| 225 | if (directory) { |
| 226 | if (closedir(directory)) { |
| 227 | /* |
| 228 | * We don't want to override the error since there is |
| 229 | * nothing could do. |
| 230 | */ |
| 231 | perror("Failed to close plug-in directory"); |
| 232 | } |
| 233 | } |
| 234 | free(entry); |
| 235 | free(file_path); |
| 236 | return ret; |
| 237 | } |
| 238 | |
| 239 | static |
| 240 | void bt_component_factory_destroy(struct bt_object *obj) |
| 241 | { |
| 242 | struct bt_component_factory *factory = NULL; |
| 243 | |
| 244 | assert(obj); |
| 245 | factory = container_of(obj, struct bt_component_factory, base); |
| 246 | |
| 247 | if (factory->component_classes) { |
| 248 | g_ptr_array_free(factory->component_classes, TRUE); |
| 249 | } |
| 250 | g_free(factory); |
| 251 | } |
| 252 | |
| 253 | struct bt_component_factory *bt_component_factory_create(void) |
| 254 | { |
| 255 | struct bt_component_factory *factory; |
| 256 | |
| 257 | factory = g_new0(struct bt_component_factory, 1); |
| 258 | if (!factory) { |
| 259 | goto end; |
| 260 | } |
| 261 | |
| 262 | bt_object_init(factory, bt_component_factory_destroy); |
| 263 | factory->component_classes = g_ptr_array_new_with_free_func( |
| 264 | (GDestroyNotify) bt_put); |
| 265 | if (!factory->component_classes) { |
| 266 | goto error; |
| 267 | } |
| 268 | end: |
| 269 | return factory; |
| 270 | error: |
| 271 | BT_PUT(factory); |
| 272 | return factory; |
| 273 | } |
| 274 | |
| 275 | int bt_component_factory_get_component_class_count( |
| 276 | struct bt_component_factory *factory) |
| 277 | { |
| 278 | return factory ? factory->component_classes->len : -1; |
| 279 | } |
| 280 | |
| 281 | struct bt_component_class *bt_component_factory_get_component_class_index( |
| 282 | struct bt_component_factory *factory, int index) |
| 283 | { |
| 284 | struct bt_component_class *component_class = NULL; |
| 285 | |
| 286 | if (!factory || index < 0 || index >= factory->component_classes->len) { |
| 287 | goto end; |
| 288 | } |
| 289 | |
| 290 | component_class = bt_get(g_ptr_array_index( |
| 291 | factory->component_classes, index)); |
| 292 | end: |
| 293 | return component_class; |
| 294 | } |
| 295 | |
| 296 | struct bt_component_class *bt_component_factory_get_component_class( |
| 297 | struct bt_component_factory *factory, |
| 298 | const char *plugin_name, enum bt_component_type type, |
| 299 | const char *component_name) |
| 300 | { |
| 301 | size_t i; |
| 302 | struct bt_component_class *component_class = NULL; |
| 303 | |
| 304 | if (!factory || (!plugin_name && !component_name && |
| 305 | type == BT_COMPONENT_TYPE_UNKNOWN)) { |
| 306 | /* At least one criterion must be provided. */ |
| 307 | goto no_match; |
| 308 | } |
| 309 | |
| 310 | for (i = 0; i < factory->component_classes->len; i++) { |
| 311 | struct bt_plugin *plugin = NULL; |
| 312 | |
| 313 | component_class = g_ptr_array_index(factory->component_classes, |
| 314 | i); |
| 315 | plugin = bt_component_class_get_plugin(component_class); |
| 316 | assert(plugin); |
| 317 | |
| 318 | if (type != BT_COMPONENT_TYPE_UNKNOWN) { |
| 319 | if (type != bt_component_class_get_type( |
| 320 | component_class)) { |
| 321 | bt_put(plugin); |
| 322 | continue; |
| 323 | } |
| 324 | } |
| 325 | |
| 326 | if (plugin_name) { |
| 327 | const char *cur_plugin_name = bt_plugin_get_name( |
| 328 | plugin); |
| 329 | |
| 330 | assert(cur_plugin_name); |
| 331 | if (strcmp(plugin_name, cur_plugin_name)) { |
| 332 | bt_put(plugin); |
| 333 | continue; |
| 334 | } |
| 335 | } |
| 336 | |
| 337 | if (component_name) { |
| 338 | const char *cur_cc_name = bt_component_class_get_name( |
| 339 | component_class); |
| 340 | |
| 341 | assert(cur_cc_name); |
| 342 | if (strcmp(component_name, cur_cc_name)) { |
| 343 | bt_put(plugin); |
| 344 | continue; |
| 345 | } |
| 346 | } |
| 347 | |
| 348 | bt_put(plugin); |
| 349 | /* All criteria met. */ |
| 350 | goto match; |
| 351 | } |
| 352 | |
| 353 | no_match: |
| 354 | return NULL; |
| 355 | match: |
| 356 | return bt_get(component_class); |
| 357 | } |
| 358 | |
| 359 | static |
| 360 | enum bt_component_factory_status _bt_component_factory_load( |
| 361 | struct bt_component_factory *factory, const char *path, |
| 362 | bool recursive) |
| 363 | { |
| 364 | enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK; |
| 365 | |
| 366 | if (!factory || !path) { |
| 367 | ret = BT_COMPONENT_FACTORY_STATUS_INVAL; |
| 368 | goto end; |
| 369 | } |
| 370 | |
| 371 | if (!g_file_test(path, G_FILE_TEST_EXISTS)) { |
| 372 | ret = BT_COMPONENT_FACTORY_STATUS_NOENT; |
| 373 | goto end; |
| 374 | } |
| 375 | |
| 376 | if (g_file_test(path, G_FILE_TEST_IS_DIR)) { |
| 377 | ret = bt_component_factory_load_dir(factory, path, recursive); |
| 378 | } else if (g_file_test(path, G_FILE_TEST_IS_REGULAR) || |
| 379 | g_file_test(path, G_FILE_TEST_IS_SYMLINK)) { |
| 380 | ret = bt_component_factory_load_file(factory, path); |
| 381 | } else { |
| 382 | ret = BT_COMPONENT_FACTORY_STATUS_INVAL; |
| 383 | goto end; |
| 384 | } |
| 385 | end: |
| 386 | return ret; |
| 387 | } |
| 388 | |
| 389 | enum bt_component_factory_status bt_component_factory_load_recursive( |
| 390 | struct bt_component_factory *factory, const char *path) |
| 391 | { |
| 392 | return _bt_component_factory_load(factory, path, true); |
| 393 | } |
| 394 | |
| 395 | enum bt_component_factory_status bt_component_factory_load( |
| 396 | struct bt_component_factory *factory, const char *path) |
| 397 | { |
| 398 | return _bt_component_factory_load(factory, path, false); |
| 399 | } |
| 400 | |
| 401 | static |
| 402 | enum bt_component_factory_status |
| 403 | add_component_class(struct bt_component_factory *factory, const char *name, |
| 404 | const char *description, bt_component_init_cb init, |
| 405 | enum bt_component_type type) |
| 406 | { |
| 407 | struct bt_component_class *component_class; |
| 408 | enum bt_component_factory_status ret = BT_COMPONENT_FACTORY_STATUS_OK; |
| 409 | |
| 410 | if (!factory || !name || !init) { |
| 411 | ret = BT_COMPONENT_FACTORY_STATUS_INVAL; |
| 412 | goto end; |
| 413 | } |
| 414 | assert(factory->current_plugin); |
| 415 | |
| 416 | /* |
| 417 | * Ensure this component class does not clash with a currently |
| 418 | * registered class. |
| 419 | */ |
| 420 | component_class = bt_component_factory_get_component_class(factory, |
| 421 | bt_plugin_get_name(factory->current_plugin), type, name); |
| 422 | if (component_class) { |
| 423 | struct bt_plugin *plugin = bt_component_class_get_plugin( |
| 424 | component_class); |
| 425 | |
| 426 | printf_warning("Duplicate component class registration attempted. Component class %s being registered by plugin %s (path: %s) conflicts with one already registered by plugin %s (path: %s)", |
| 427 | name, bt_plugin_get_name(factory->current_plugin), |
| 428 | bt_plugin_get_path(factory->current_plugin), |
| 429 | bt_plugin_get_name(plugin), |
| 430 | bt_plugin_get_path(plugin)); |
| 431 | ret = BT_COMPONENT_FACTORY_STATUS_DUPLICATE; |
| 432 | BT_PUT(component_class); |
| 433 | bt_put(plugin); |
| 434 | goto end; |
| 435 | } |
| 436 | |
| 437 | component_class = bt_component_class_create(type, name, description, |
| 438 | init, factory->current_plugin); |
| 439 | g_ptr_array_add(factory->component_classes, component_class); |
| 440 | end: |
| 441 | return ret; |
| 442 | } |
| 443 | |
| 444 | enum bt_component_factory_status |
| 445 | bt_component_factory_register_source_component_class( |
| 446 | struct bt_component_factory *factory, const char *name, |
| 447 | const char *description, bt_component_init_cb init) |
| 448 | { |
| 449 | return add_component_class(factory, name, description, init, |
| 450 | BT_COMPONENT_TYPE_SOURCE); |
| 451 | } |
| 452 | |
| 453 | enum bt_component_factory_status |
| 454 | bt_component_factory_register_sink_component_class( |
| 455 | struct bt_component_factory *factory, const char *name, |
| 456 | const char *description, bt_component_init_cb init) |
| 457 | { |
| 458 | return add_component_class(factory, name, description, init, |
| 459 | BT_COMPONENT_TYPE_SINK); |
| 460 | } |