| 1 | /* |
| 2 | * Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 3 | * |
| 4 | * SPDX-License-Identifier: LGPL-2.1-only |
| 5 | * |
| 6 | */ |
| 7 | |
| 8 | #include <lttng/destruction-handle.h> |
| 9 | #include <lttng/rotation.h> |
| 10 | |
| 11 | #include <common/optional.hpp> |
| 12 | #include <common/compat/poll.hpp> |
| 13 | #include <common/compat/time.hpp> |
| 14 | #include <common/macros.hpp> |
| 15 | #include <common/compat/poll.hpp> |
| 16 | #include <common/dynamic-buffer.hpp> |
| 17 | #include <common/buffer-view.hpp> |
| 18 | #include <common/sessiond-comm/sessiond-comm.hpp> |
| 19 | #include <lttng/location-internal.hpp> |
| 20 | #include "lttng-ctl-helper.hpp" |
| 21 | |
| 22 | #include <algorithm> |
| 23 | #include <stdbool.h> |
| 24 | |
| 25 | enum communication_state { |
| 26 | COMMUNICATION_STATE_RECEIVE_LTTNG_MSG, |
| 27 | COMMUNICATION_STATE_RECEIVE_COMMAND_HEADER, |
| 28 | COMMUNICATION_STATE_RECEIVE_PAYLOAD, |
| 29 | COMMUNICATION_STATE_END, |
| 30 | COMMUNICATION_STATE_ERROR, |
| 31 | }; |
| 32 | |
| 33 | struct lttng_destruction_handle { |
| 34 | LTTNG_OPTIONAL(enum lttng_error_code) destruction_return_code; |
| 35 | LTTNG_OPTIONAL(enum lttng_rotation_state) rotation_state; |
| 36 | struct lttng_trace_archive_location *location; |
| 37 | struct { |
| 38 | int socket; |
| 39 | struct lttng_poll_event events; |
| 40 | size_t bytes_left_to_receive; |
| 41 | enum communication_state state; |
| 42 | struct lttng_dynamic_buffer buffer; |
| 43 | LTTNG_OPTIONAL(size_t) data_size; |
| 44 | } communication; |
| 45 | }; |
| 46 | |
| 47 | void lttng_destruction_handle_destroy(struct lttng_destruction_handle *handle) |
| 48 | { |
| 49 | int ret; |
| 50 | |
| 51 | if (!handle) { |
| 52 | return; |
| 53 | } |
| 54 | |
| 55 | if (handle->communication.socket >= 0) { |
| 56 | ret = close(handle->communication.socket); |
| 57 | if (ret) { |
| 58 | PERROR("Failed to close lttng-sessiond command socket"); |
| 59 | } |
| 60 | } |
| 61 | lttng_poll_clean(&handle->communication.events); |
| 62 | lttng_dynamic_buffer_reset(&handle->communication.buffer); |
| 63 | lttng_trace_archive_location_put(handle->location); |
| 64 | free(handle); |
| 65 | } |
| 66 | |
| 67 | static |
| 68 | struct lttng_destruction_handle *lttng_destruction_handle_create( |
| 69 | int sessiond_socket) |
| 70 | { |
| 71 | int ret; |
| 72 | struct lttng_destruction_handle *handle = zmalloc<lttng_destruction_handle>(); |
| 73 | |
| 74 | if (!handle) { |
| 75 | goto end; |
| 76 | } |
| 77 | lttng_dynamic_buffer_init(&handle->communication.buffer); |
| 78 | handle->communication.socket = sessiond_socket; |
| 79 | ret = lttng_poll_create(&handle->communication.events, 1, 0); |
| 80 | if (ret) { |
| 81 | goto error; |
| 82 | } |
| 83 | |
| 84 | ret = lttng_poll_add(&handle->communication.events, sessiond_socket, |
| 85 | LPOLLIN | LPOLLHUP | LPOLLRDHUP | LPOLLERR); |
| 86 | if (ret) { |
| 87 | goto error; |
| 88 | } |
| 89 | |
| 90 | handle->communication.bytes_left_to_receive = |
| 91 | sizeof(struct lttcomm_lttng_msg); |
| 92 | handle->communication.state = COMMUNICATION_STATE_RECEIVE_LTTNG_MSG; |
| 93 | end: |
| 94 | return handle; |
| 95 | error: |
| 96 | lttng_destruction_handle_destroy(handle); |
| 97 | return NULL; |
| 98 | } |
| 99 | |
| 100 | static |
| 101 | int handle_state_transition(struct lttng_destruction_handle *handle) |
| 102 | { |
| 103 | int ret = 0; |
| 104 | |
| 105 | LTTNG_ASSERT(handle->communication.bytes_left_to_receive == 0); |
| 106 | |
| 107 | switch (handle->communication.state) { |
| 108 | case COMMUNICATION_STATE_RECEIVE_LTTNG_MSG: |
| 109 | { |
| 110 | const struct lttcomm_lttng_msg *msg = |
| 111 | (typeof(msg)) handle->communication.buffer.data; |
| 112 | |
| 113 | LTTNG_OPTIONAL_SET(&handle->destruction_return_code, |
| 114 | (enum lttng_error_code) msg->ret_code); |
| 115 | if (handle->destruction_return_code.value != LTTNG_OK) { |
| 116 | handle->communication.state = COMMUNICATION_STATE_END; |
| 117 | break; |
| 118 | } else if (msg->cmd_header_size != sizeof(struct lttcomm_session_destroy_command_header) || |
| 119 | msg->data_size > DEFAULT_MAX_TRACE_ARCHIVE_LOCATION_PAYLOAD_SIZE) { |
| 120 | handle->communication.state = COMMUNICATION_STATE_ERROR; |
| 121 | ret = -1; |
| 122 | break; |
| 123 | } |
| 124 | |
| 125 | handle->communication.state = |
| 126 | COMMUNICATION_STATE_RECEIVE_COMMAND_HEADER; |
| 127 | handle->communication.bytes_left_to_receive = |
| 128 | msg->cmd_header_size; |
| 129 | LTTNG_OPTIONAL_SET(&handle->communication.data_size, |
| 130 | msg->data_size); |
| 131 | ret = lttng_dynamic_buffer_set_size( |
| 132 | &handle->communication.buffer, 0); |
| 133 | LTTNG_ASSERT(!ret); |
| 134 | break; |
| 135 | } |
| 136 | case COMMUNICATION_STATE_RECEIVE_COMMAND_HEADER: |
| 137 | { |
| 138 | const struct lttcomm_session_destroy_command_header *hdr = |
| 139 | (typeof(hdr)) handle->communication.buffer.data; |
| 140 | |
| 141 | LTTNG_OPTIONAL_SET(&handle->rotation_state, |
| 142 | (enum lttng_rotation_state) hdr->rotation_state); |
| 143 | switch (handle->rotation_state.value) { |
| 144 | case LTTNG_ROTATION_STATE_COMPLETED: |
| 145 | handle->communication.state = |
| 146 | COMMUNICATION_STATE_RECEIVE_PAYLOAD; |
| 147 | handle->communication.bytes_left_to_receive = |
| 148 | LTTNG_OPTIONAL_GET(handle->communication.data_size); |
| 149 | break; |
| 150 | case LTTNG_ROTATION_STATE_ERROR: |
| 151 | case LTTNG_ROTATION_STATE_NO_ROTATION: |
| 152 | handle->communication.state = COMMUNICATION_STATE_END; |
| 153 | break; |
| 154 | default: |
| 155 | handle->communication.state = COMMUNICATION_STATE_ERROR; |
| 156 | ret = -1; |
| 157 | break; |
| 158 | } |
| 159 | break; |
| 160 | } |
| 161 | case COMMUNICATION_STATE_RECEIVE_PAYLOAD: |
| 162 | { |
| 163 | ssize_t location_ret; |
| 164 | struct lttng_trace_archive_location *location; |
| 165 | const struct lttng_buffer_view view = |
| 166 | lttng_buffer_view_from_dynamic_buffer( |
| 167 | &handle->communication.buffer, 0, -1); |
| 168 | |
| 169 | location_ret = lttng_trace_archive_location_create_from_buffer( |
| 170 | &view, &location); |
| 171 | if (location_ret < 0) { |
| 172 | ERR("Failed to deserialize trace archive location"); |
| 173 | handle->communication.state = COMMUNICATION_STATE_ERROR; |
| 174 | ret = -1; |
| 175 | break; |
| 176 | } else { |
| 177 | /* Ownership is transferred to the destruction handle. */ |
| 178 | handle->location = location; |
| 179 | handle->communication.state = COMMUNICATION_STATE_END; |
| 180 | } |
| 181 | break; |
| 182 | } |
| 183 | default: |
| 184 | abort(); |
| 185 | } |
| 186 | |
| 187 | /* Clear reception buffer on state transition. */ |
| 188 | if (lttng_dynamic_buffer_set_size(&handle->communication.buffer, 0)) { |
| 189 | abort(); |
| 190 | } |
| 191 | return ret; |
| 192 | } |
| 193 | |
| 194 | static |
| 195 | int handle_incoming_data(struct lttng_destruction_handle *handle) |
| 196 | { |
| 197 | int ret; |
| 198 | ssize_t comm_ret; |
| 199 | const size_t original_buffer_size = handle->communication.buffer.size; |
| 200 | |
| 201 | /* Reserve space for reception. */ |
| 202 | ret = lttng_dynamic_buffer_set_size(&handle->communication.buffer, |
| 203 | original_buffer_size + handle->communication.bytes_left_to_receive); |
| 204 | if (ret) { |
| 205 | goto end; |
| 206 | } |
| 207 | |
| 208 | comm_ret = lttcomm_recv_unix_sock(handle->communication.socket, |
| 209 | handle->communication.buffer.data + original_buffer_size, |
| 210 | handle->communication.bytes_left_to_receive); |
| 211 | if (comm_ret <= 0) { |
| 212 | ret = -1; |
| 213 | goto end; |
| 214 | } |
| 215 | |
| 216 | handle->communication.bytes_left_to_receive -= comm_ret; |
| 217 | if (handle->communication.bytes_left_to_receive == 0) { |
| 218 | ret = handle_state_transition(handle); |
| 219 | } else { |
| 220 | ret = lttng_dynamic_buffer_set_size( |
| 221 | &handle->communication.buffer, |
| 222 | original_buffer_size + comm_ret); |
| 223 | } |
| 224 | end: |
| 225 | return ret; |
| 226 | } |
| 227 | |
| 228 | enum lttng_destruction_handle_status |
| 229 | lttng_destruction_handle_wait_for_completion( |
| 230 | struct lttng_destruction_handle *handle, int timeout_ms) |
| 231 | { |
| 232 | enum lttng_destruction_handle_status status; |
| 233 | unsigned long time_left_ms = 0; |
| 234 | const bool has_timeout = timeout_ms > 0; |
| 235 | struct timespec initial_time; |
| 236 | |
| 237 | if (!handle) { |
| 238 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 239 | goto end; |
| 240 | } |
| 241 | |
| 242 | if (handle->communication.state == COMMUNICATION_STATE_ERROR) { |
| 243 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 244 | goto end; |
| 245 | } else if (handle->communication.state == COMMUNICATION_STATE_END) { |
| 246 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED; |
| 247 | goto end; |
| 248 | } |
| 249 | if (has_timeout) { |
| 250 | int ret = lttng_clock_gettime(CLOCK_MONOTONIC, &initial_time); |
| 251 | if (ret) { |
| 252 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 253 | goto end; |
| 254 | } |
| 255 | time_left_ms = (unsigned long) timeout_ms; |
| 256 | } |
| 257 | |
| 258 | while (handle->communication.state != COMMUNICATION_STATE_END && |
| 259 | (time_left_ms || !has_timeout)) { |
| 260 | int ret; |
| 261 | uint32_t revents; |
| 262 | struct timespec current_time, diff; |
| 263 | unsigned long diff_ms; |
| 264 | |
| 265 | ret = lttng_poll_wait(&handle->communication.events, |
| 266 | has_timeout ? time_left_ms : -1); |
| 267 | if (ret == 0) { |
| 268 | /* timeout */ |
| 269 | break; |
| 270 | } else if (ret < 0) { |
| 271 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 272 | goto end; |
| 273 | } |
| 274 | |
| 275 | /* The sessiond connection socket is the only monitored fd. */ |
| 276 | revents = LTTNG_POLL_GETEV(&handle->communication.events, 0); |
| 277 | if (revents & LPOLLIN) { |
| 278 | ret = handle_incoming_data(handle); |
| 279 | if (ret) { |
| 280 | handle->communication.state = |
| 281 | COMMUNICATION_STATE_ERROR; |
| 282 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 283 | goto end; |
| 284 | } |
| 285 | } else { |
| 286 | handle->communication.state = COMMUNICATION_STATE_ERROR; |
| 287 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 288 | goto end; |
| 289 | } |
| 290 | if (!has_timeout) { |
| 291 | continue; |
| 292 | } |
| 293 | |
| 294 | ret = lttng_clock_gettime(CLOCK_MONOTONIC, ¤t_time); |
| 295 | if (ret) { |
| 296 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 297 | goto end; |
| 298 | } |
| 299 | diff = timespec_abs_diff(initial_time, current_time); |
| 300 | ret = timespec_to_ms(diff, &diff_ms); |
| 301 | if (ret) { |
| 302 | ERR("Failed to compute elapsed time while waiting for completion"); |
| 303 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 304 | goto end; |
| 305 | } |
| 306 | DBG("%lums elapsed while waiting for session destruction completion", |
| 307 | diff_ms); |
| 308 | diff_ms = std::max(diff_ms, 1UL); |
| 309 | diff_ms = std::min(diff_ms, time_left_ms); |
| 310 | time_left_ms -= diff_ms; |
| 311 | } |
| 312 | |
| 313 | status = handle->communication.state == COMMUNICATION_STATE_END ? |
| 314 | LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED : |
| 315 | LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT; |
| 316 | end: |
| 317 | return status; |
| 318 | } |
| 319 | |
| 320 | enum lttng_destruction_handle_status |
| 321 | lttng_destruction_handle_get_rotation_state( |
| 322 | const struct lttng_destruction_handle *handle, |
| 323 | enum lttng_rotation_state *rotation_state) |
| 324 | { |
| 325 | enum lttng_destruction_handle_status status = |
| 326 | LTTNG_DESTRUCTION_HANDLE_STATUS_OK; |
| 327 | |
| 328 | if (!handle || !rotation_state) { |
| 329 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 330 | goto end; |
| 331 | } |
| 332 | |
| 333 | if (!handle->rotation_state.is_set) { |
| 334 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 335 | goto end; |
| 336 | } |
| 337 | *rotation_state = handle->rotation_state.value; |
| 338 | end: |
| 339 | return status; |
| 340 | } |
| 341 | |
| 342 | enum lttng_destruction_handle_status |
| 343 | lttng_destruction_handle_get_archive_location( |
| 344 | const struct lttng_destruction_handle *handle, |
| 345 | const struct lttng_trace_archive_location **location) |
| 346 | { |
| 347 | enum lttng_destruction_handle_status status = |
| 348 | LTTNG_DESTRUCTION_HANDLE_STATUS_OK; |
| 349 | |
| 350 | if (!handle || !location) { |
| 351 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 352 | goto end; |
| 353 | } |
| 354 | |
| 355 | if (!handle->location) { |
| 356 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 357 | goto end; |
| 358 | } |
| 359 | *location = handle->location; |
| 360 | end: |
| 361 | return status; |
| 362 | } |
| 363 | |
| 364 | enum lttng_destruction_handle_status |
| 365 | lttng_destruction_handle_get_result( |
| 366 | const struct lttng_destruction_handle *handle, |
| 367 | enum lttng_error_code *result) |
| 368 | { |
| 369 | enum lttng_destruction_handle_status status = |
| 370 | LTTNG_DESTRUCTION_HANDLE_STATUS_OK; |
| 371 | |
| 372 | if (!handle || !result) { |
| 373 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 374 | goto end; |
| 375 | } |
| 376 | |
| 377 | if (!handle->destruction_return_code.is_set) { |
| 378 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 379 | goto end; |
| 380 | } |
| 381 | *result = handle->destruction_return_code.value; |
| 382 | end: |
| 383 | return status; |
| 384 | } |
| 385 | |
| 386 | enum lttng_error_code lttng_destroy_session_ext(const char *session_name, |
| 387 | struct lttng_destruction_handle **_handle) |
| 388 | { |
| 389 | int ret; |
| 390 | ssize_t comm_ret; |
| 391 | enum lttng_error_code ret_code = LTTNG_OK; |
| 392 | struct lttcomm_session_msg lsm = { |
| 393 | .cmd_type = LTTNG_DESTROY_SESSION, |
| 394 | .session = {}, |
| 395 | .domain = {}, |
| 396 | .u = {}, |
| 397 | .fd_count = 0, |
| 398 | }; |
| 399 | int sessiond_socket = -1; |
| 400 | struct lttng_destruction_handle *handle = NULL; |
| 401 | |
| 402 | if (!session_name) { |
| 403 | ret_code = LTTNG_ERR_INVALID; |
| 404 | goto error; |
| 405 | } |
| 406 | |
| 407 | ret = lttng_strncpy(lsm.session.name, session_name, |
| 408 | sizeof(lsm.session.name)); |
| 409 | if (ret) { |
| 410 | ret_code = LTTNG_ERR_INVALID; |
| 411 | goto error; |
| 412 | } |
| 413 | |
| 414 | ret = connect_sessiond(); |
| 415 | if (ret < 0) { |
| 416 | ret_code = LTTNG_ERR_NO_SESSIOND; |
| 417 | goto error; |
| 418 | } else { |
| 419 | sessiond_socket = ret; |
| 420 | } |
| 421 | |
| 422 | handle = lttng_destruction_handle_create(sessiond_socket); |
| 423 | if (!handle) { |
| 424 | ret_code = LTTNG_ERR_NOMEM; |
| 425 | goto error; |
| 426 | } |
| 427 | |
| 428 | comm_ret = lttcomm_send_creds_unix_sock(sessiond_socket, &lsm, sizeof(lsm)); |
| 429 | if (comm_ret < 0) { |
| 430 | ret_code = LTTNG_ERR_FATAL; |
| 431 | goto error; |
| 432 | } |
| 433 | sessiond_socket = -1; |
| 434 | |
| 435 | /* Transfer the handle to the caller. */ |
| 436 | if (_handle) { |
| 437 | *_handle = handle; |
| 438 | handle = NULL; |
| 439 | } |
| 440 | error: |
| 441 | if (sessiond_socket >= 0) { |
| 442 | ret = close(sessiond_socket); |
| 443 | if (ret < 0) { |
| 444 | PERROR("Failed to close the LTTng session daemon connection socket"); |
| 445 | } |
| 446 | } |
| 447 | if (handle) { |
| 448 | lttng_destruction_handle_destroy(handle); |
| 449 | } |
| 450 | return ret_code; |
| 451 | } |