| 1 | /* |
| 2 | * Copyright (C) 2019 - Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU Lesser General Public License, version 2.1 only, |
| 6 | * as published by the Free Software Foundation. |
| 7 | * |
| 8 | * This library is distributed in the hope that it will be useful, but WITHOUT |
| 9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License |
| 11 | * for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU Lesser General Public License |
| 14 | * along with this library; if not, write to the Free Software Foundation, |
| 15 | * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 16 | */ |
| 17 | |
| 18 | #include <lttng/destruction-handle.h> |
| 19 | #include <lttng/rotation.h> |
| 20 | |
| 21 | #include <common/optional.h> |
| 22 | #include <common/compat/poll.h> |
| 23 | #include <common/compat/time.h> |
| 24 | #include <common/macros.h> |
| 25 | #include <common/compat/poll.h> |
| 26 | #include <common/dynamic-buffer.h> |
| 27 | #include <common/buffer-view.h> |
| 28 | #include <common/sessiond-comm/sessiond-comm.h> |
| 29 | #include <lttng/location-internal.h> |
| 30 | #include "lttng-ctl-helper.h" |
| 31 | |
| 32 | #include <stdbool.h> |
| 33 | |
| 34 | enum communication_state { |
| 35 | COMMUNICATION_STATE_RECEIVE_LTTNG_MSG, |
| 36 | COMMUNICATION_STATE_RECEIVE_COMMAND_HEADER, |
| 37 | COMMUNICATION_STATE_RECEIVE_PAYLOAD, |
| 38 | COMMUNICATION_STATE_END, |
| 39 | COMMUNICATION_STATE_ERROR, |
| 40 | }; |
| 41 | |
| 42 | struct lttng_destruction_handle { |
| 43 | LTTNG_OPTIONAL(enum lttng_error_code) destruction_return_code; |
| 44 | LTTNG_OPTIONAL(enum lttng_rotation_state) rotation_state; |
| 45 | struct lttng_trace_archive_location *location; |
| 46 | struct { |
| 47 | int socket; |
| 48 | struct lttng_poll_event events; |
| 49 | size_t bytes_left_to_receive; |
| 50 | enum communication_state state; |
| 51 | struct lttng_dynamic_buffer buffer; |
| 52 | LTTNG_OPTIONAL(size_t) data_size; |
| 53 | } communication; |
| 54 | }; |
| 55 | |
| 56 | void lttng_destruction_handle_destroy(struct lttng_destruction_handle *handle) |
| 57 | { |
| 58 | int ret; |
| 59 | |
| 60 | if (!handle) { |
| 61 | return; |
| 62 | } |
| 63 | |
| 64 | if (handle->communication.socket >= 0) { |
| 65 | ret = close(handle->communication.socket); |
| 66 | if (ret) { |
| 67 | PERROR("Failed to close lttng-sessiond command socket"); |
| 68 | } |
| 69 | } |
| 70 | lttng_poll_clean(&handle->communication.events); |
| 71 | lttng_dynamic_buffer_reset(&handle->communication.buffer); |
| 72 | lttng_trace_archive_location_destroy(handle->location); |
| 73 | free(handle); |
| 74 | } |
| 75 | |
| 76 | static |
| 77 | struct lttng_destruction_handle *lttng_destruction_handle_create( |
| 78 | int sessiond_socket) |
| 79 | { |
| 80 | int ret; |
| 81 | struct lttng_destruction_handle *handle = zmalloc(sizeof(*handle)); |
| 82 | |
| 83 | if (!handle) { |
| 84 | goto end; |
| 85 | } |
| 86 | lttng_dynamic_buffer_init(&handle->communication.buffer); |
| 87 | handle->communication.socket = sessiond_socket; |
| 88 | ret = lttng_poll_create(&handle->communication.events, 1, 0); |
| 89 | if (ret) { |
| 90 | goto error; |
| 91 | } |
| 92 | |
| 93 | ret = lttng_poll_add(&handle->communication.events, sessiond_socket, |
| 94 | LPOLLIN | LPOLLHUP | LPOLLRDHUP | LPOLLERR); |
| 95 | if (ret) { |
| 96 | goto error; |
| 97 | } |
| 98 | |
| 99 | handle->communication.bytes_left_to_receive = |
| 100 | sizeof(struct lttcomm_lttng_msg); |
| 101 | handle->communication.state = COMMUNICATION_STATE_RECEIVE_LTTNG_MSG; |
| 102 | end: |
| 103 | return handle; |
| 104 | error: |
| 105 | lttng_destruction_handle_destroy(handle); |
| 106 | return NULL; |
| 107 | } |
| 108 | |
| 109 | static |
| 110 | int handle_state_transition(struct lttng_destruction_handle *handle) |
| 111 | { |
| 112 | int ret = 0; |
| 113 | |
| 114 | assert(handle->communication.bytes_left_to_receive == 0); |
| 115 | |
| 116 | switch (handle->communication.state) { |
| 117 | case COMMUNICATION_STATE_RECEIVE_LTTNG_MSG: |
| 118 | { |
| 119 | const struct lttcomm_lttng_msg *msg = |
| 120 | (typeof(msg)) handle->communication.buffer.data; |
| 121 | |
| 122 | LTTNG_OPTIONAL_SET(&handle->destruction_return_code, |
| 123 | (enum lttng_error_code) msg->ret_code); |
| 124 | if (handle->destruction_return_code.value != LTTNG_OK) { |
| 125 | handle->communication.state = COMMUNICATION_STATE_END; |
| 126 | break; |
| 127 | } else if (msg->cmd_header_size != sizeof(struct lttcomm_session_destroy_command_header) || |
| 128 | msg->data_size > DEFAULT_MAX_TRACE_ARCHIVE_LOCATION_PAYLOAD_SIZE) { |
| 129 | handle->communication.state = COMMUNICATION_STATE_ERROR; |
| 130 | ret = -1; |
| 131 | break; |
| 132 | } |
| 133 | |
| 134 | handle->communication.state = |
| 135 | COMMUNICATION_STATE_RECEIVE_COMMAND_HEADER; |
| 136 | handle->communication.bytes_left_to_receive = |
| 137 | msg->cmd_header_size; |
| 138 | LTTNG_OPTIONAL_SET(&handle->communication.data_size, |
| 139 | msg->data_size); |
| 140 | ret = lttng_dynamic_buffer_set_size( |
| 141 | &handle->communication.buffer, 0); |
| 142 | assert(!ret); |
| 143 | break; |
| 144 | } |
| 145 | case COMMUNICATION_STATE_RECEIVE_COMMAND_HEADER: |
| 146 | { |
| 147 | const struct lttcomm_session_destroy_command_header *hdr = |
| 148 | (typeof(hdr)) handle->communication.buffer.data; |
| 149 | |
| 150 | LTTNG_OPTIONAL_SET(&handle->rotation_state, |
| 151 | (enum lttng_rotation_state) hdr->rotation_state); |
| 152 | switch (handle->rotation_state.value) { |
| 153 | case LTTNG_ROTATION_STATE_COMPLETED: |
| 154 | handle->communication.state = |
| 155 | COMMUNICATION_STATE_RECEIVE_PAYLOAD; |
| 156 | handle->communication.bytes_left_to_receive = |
| 157 | LTTNG_OPTIONAL_GET(handle->communication.data_size); |
| 158 | break; |
| 159 | case LTTNG_ROTATION_STATE_ERROR: |
| 160 | case LTTNG_ROTATION_STATE_NO_ROTATION: |
| 161 | handle->communication.state = COMMUNICATION_STATE_END; |
| 162 | break; |
| 163 | default: |
| 164 | handle->communication.state = COMMUNICATION_STATE_ERROR; |
| 165 | ret = -1; |
| 166 | break; |
| 167 | } |
| 168 | break; |
| 169 | } |
| 170 | case COMMUNICATION_STATE_RECEIVE_PAYLOAD: |
| 171 | { |
| 172 | ssize_t location_ret; |
| 173 | struct lttng_trace_archive_location *location; |
| 174 | const struct lttng_buffer_view view = |
| 175 | lttng_buffer_view_from_dynamic_buffer( |
| 176 | &handle->communication.buffer, 0, -1); |
| 177 | |
| 178 | location_ret = lttng_trace_archive_location_create_from_buffer( |
| 179 | &view, &location); |
| 180 | if (location_ret < 0) { |
| 181 | ERR("Failed to deserialize trace archive location"); |
| 182 | handle->communication.state = COMMUNICATION_STATE_ERROR; |
| 183 | ret = -1; |
| 184 | break; |
| 185 | } else { |
| 186 | handle->location = location; |
| 187 | handle->communication.state = COMMUNICATION_STATE_END; |
| 188 | } |
| 189 | break; |
| 190 | } |
| 191 | default: |
| 192 | abort(); |
| 193 | } |
| 194 | |
| 195 | /* Clear reception buffer on state transition. */ |
| 196 | if (lttng_dynamic_buffer_set_size(&handle->communication.buffer, 0)) { |
| 197 | abort(); |
| 198 | } |
| 199 | return ret; |
| 200 | } |
| 201 | |
| 202 | static |
| 203 | int handle_incoming_data(struct lttng_destruction_handle *handle) |
| 204 | { |
| 205 | int ret; |
| 206 | ssize_t comm_ret; |
| 207 | const size_t original_buffer_size = handle->communication.buffer.size; |
| 208 | |
| 209 | /* Reserve space for reception. */ |
| 210 | ret = lttng_dynamic_buffer_set_size(&handle->communication.buffer, |
| 211 | original_buffer_size + handle->communication.bytes_left_to_receive); |
| 212 | if (ret) { |
| 213 | goto end; |
| 214 | } |
| 215 | |
| 216 | comm_ret = lttcomm_recv_unix_sock(handle->communication.socket, |
| 217 | handle->communication.buffer.data + original_buffer_size, |
| 218 | handle->communication.bytes_left_to_receive); |
| 219 | if (comm_ret <= 0) { |
| 220 | ret = -1; |
| 221 | goto end; |
| 222 | } |
| 223 | |
| 224 | handle->communication.bytes_left_to_receive -= comm_ret; |
| 225 | if (handle->communication.bytes_left_to_receive == 0) { |
| 226 | ret = handle_state_transition(handle); |
| 227 | } else { |
| 228 | ret = lttng_dynamic_buffer_set_size( |
| 229 | &handle->communication.buffer, |
| 230 | original_buffer_size + comm_ret); |
| 231 | } |
| 232 | end: |
| 233 | return ret; |
| 234 | } |
| 235 | |
| 236 | enum lttng_destruction_handle_status |
| 237 | lttng_destruction_handle_wait_for_completion( |
| 238 | struct lttng_destruction_handle *handle, int timeout_ms) |
| 239 | { |
| 240 | int ret; |
| 241 | enum lttng_destruction_handle_status status; |
| 242 | unsigned long time_left_ms = 0; |
| 243 | const bool has_timeout = timeout_ms > 0; |
| 244 | struct timespec initial_time; |
| 245 | |
| 246 | if (handle->communication.state == COMMUNICATION_STATE_ERROR) { |
| 247 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 248 | goto end; |
| 249 | } else if (handle->communication.state == COMMUNICATION_STATE_END) { |
| 250 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED; |
| 251 | goto end; |
| 252 | } |
| 253 | if (has_timeout) { |
| 254 | ret = lttng_clock_gettime(CLOCK_MONOTONIC, &initial_time); |
| 255 | if (ret) { |
| 256 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 257 | goto end; |
| 258 | } |
| 259 | time_left_ms = (unsigned long) timeout_ms; |
| 260 | } |
| 261 | |
| 262 | while (handle->communication.state != COMMUNICATION_STATE_END && |
| 263 | (time_left_ms || !has_timeout)) { |
| 264 | int ret; |
| 265 | uint32_t revents; |
| 266 | struct timespec current_time, diff; |
| 267 | unsigned long diff_ms; |
| 268 | |
| 269 | ret = lttng_poll_wait(&handle->communication.events, |
| 270 | has_timeout ? time_left_ms : -1); |
| 271 | if (ret == 0) { |
| 272 | /* timeout */ |
| 273 | break; |
| 274 | } else if (ret < 0) { |
| 275 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 276 | goto end; |
| 277 | } |
| 278 | |
| 279 | /* The sessiond connection socket is the only monitored fd. */ |
| 280 | revents = LTTNG_POLL_GETEV(&handle->communication.events, 0); |
| 281 | if (revents & LPOLLIN) { |
| 282 | ret = handle_incoming_data(handle); |
| 283 | if (ret) { |
| 284 | handle->communication.state = |
| 285 | COMMUNICATION_STATE_ERROR; |
| 286 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 287 | goto end; |
| 288 | } |
| 289 | } else { |
| 290 | handle->communication.state = COMMUNICATION_STATE_ERROR; |
| 291 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 292 | goto end; |
| 293 | } |
| 294 | if (!has_timeout) { |
| 295 | continue; |
| 296 | } |
| 297 | |
| 298 | ret = lttng_clock_gettime(CLOCK_MONOTONIC, ¤t_time); |
| 299 | if (ret) { |
| 300 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 301 | goto end; |
| 302 | } |
| 303 | diff = timespec_abs_diff(initial_time, current_time); |
| 304 | ret = timespec_to_ms(diff, &diff_ms); |
| 305 | if (ret) { |
| 306 | ERR("Failed to compute elapsed time while waiting for completion"); |
| 307 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_ERROR; |
| 308 | goto end; |
| 309 | } |
| 310 | DBG("%lums elapsed while waiting for session destruction completion", |
| 311 | diff_ms); |
| 312 | diff_ms = max_t(unsigned long, diff_ms, 1); |
| 313 | diff_ms = min_t(unsigned long, diff_ms, time_left_ms); |
| 314 | time_left_ms -= diff_ms; |
| 315 | } |
| 316 | |
| 317 | status = handle->communication.state == COMMUNICATION_STATE_END ? |
| 318 | LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED : |
| 319 | LTTNG_DESTRUCTION_HANDLE_STATUS_TIMEOUT; |
| 320 | end: |
| 321 | return status; |
| 322 | } |
| 323 | |
| 324 | enum lttng_destruction_handle_status |
| 325 | lttng_destruction_handle_get_rotation_state( |
| 326 | const struct lttng_destruction_handle *handle, |
| 327 | enum lttng_rotation_state *rotation_state) |
| 328 | { |
| 329 | enum lttng_destruction_handle_status status = |
| 330 | LTTNG_DESTRUCTION_HANDLE_STATUS_OK; |
| 331 | |
| 332 | if (!handle->rotation_state.is_set) { |
| 333 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 334 | goto end; |
| 335 | } |
| 336 | *rotation_state = handle->rotation_state.value; |
| 337 | end: |
| 338 | return status; |
| 339 | } |
| 340 | |
| 341 | enum lttng_destruction_handle_status |
| 342 | lttng_destruction_handle_get_archive_location( |
| 343 | const struct lttng_destruction_handle *handle, |
| 344 | const struct lttng_trace_archive_location **location) |
| 345 | { |
| 346 | enum lttng_destruction_handle_status status = |
| 347 | LTTNG_DESTRUCTION_HANDLE_STATUS_OK; |
| 348 | |
| 349 | if (!handle->location) { |
| 350 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 351 | goto end; |
| 352 | } |
| 353 | *location = handle->location; |
| 354 | end: |
| 355 | return status; |
| 356 | } |
| 357 | |
| 358 | enum lttng_destruction_handle_status |
| 359 | lttng_destruction_handle_get_result( |
| 360 | const struct lttng_destruction_handle *handle, |
| 361 | enum lttng_error_code *result) |
| 362 | { |
| 363 | enum lttng_destruction_handle_status status = |
| 364 | LTTNG_DESTRUCTION_HANDLE_STATUS_OK; |
| 365 | |
| 366 | if (!handle->destruction_return_code.is_set) { |
| 367 | status = LTTNG_DESTRUCTION_HANDLE_STATUS_INVALID; |
| 368 | goto end; |
| 369 | } |
| 370 | *result = handle->destruction_return_code.value; |
| 371 | end: |
| 372 | return status; |
| 373 | } |
| 374 | |
| 375 | enum lttng_error_code lttng_destroy_session_ext(const char *session_name, |
| 376 | struct lttng_destruction_handle **_handle) |
| 377 | { |
| 378 | int ret; |
| 379 | ssize_t comm_ret; |
| 380 | enum lttng_error_code ret_code = LTTNG_OK; |
| 381 | struct lttcomm_session_msg lsm = { |
| 382 | .cmd_type = LTTNG_DESTROY_SESSION, |
| 383 | }; |
| 384 | int sessiond_socket = -1; |
| 385 | struct lttng_destruction_handle *handle = NULL; |
| 386 | |
| 387 | ret = lttng_strncpy(lsm.session.name, session_name, |
| 388 | sizeof(lsm.session.name)); |
| 389 | if (ret) { |
| 390 | ret_code = LTTNG_ERR_INVALID; |
| 391 | goto error; |
| 392 | } |
| 393 | |
| 394 | ret = connect_sessiond(); |
| 395 | if (ret < 0) { |
| 396 | ret_code = LTTNG_ERR_NO_SESSIOND; |
| 397 | goto error; |
| 398 | } else { |
| 399 | sessiond_socket = ret; |
| 400 | } |
| 401 | |
| 402 | handle = lttng_destruction_handle_create(sessiond_socket); |
| 403 | if (!handle) { |
| 404 | ret_code = LTTNG_ERR_NOMEM; |
| 405 | goto error; |
| 406 | } |
| 407 | |
| 408 | comm_ret = lttcomm_send_creds_unix_sock(sessiond_socket, &lsm, sizeof(lsm)); |
| 409 | if (comm_ret < 0) { |
| 410 | ret_code = LTTNG_ERR_FATAL; |
| 411 | goto error; |
| 412 | } |
| 413 | sessiond_socket = -1; |
| 414 | |
| 415 | /* Transfer the handle to the caller. */ |
| 416 | if (_handle) { |
| 417 | *_handle = handle; |
| 418 | handle = NULL; |
| 419 | } |
| 420 | error: |
| 421 | if (sessiond_socket >= 0) { |
| 422 | ret = close(sessiond_socket); |
| 423 | PERROR("Failed to close the LTTng session daemon connection socket"); |
| 424 | } |
| 425 | if (handle) { |
| 426 | lttng_destruction_handle_destroy(handle); |
| 427 | } |
| 428 | return ret_code; |
| 429 | } |