Commit | Line | Data |
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f2c1f0d4 | 1 | /* |
ab5be9fa MJ |
2 | * Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
3 | * Copyright (C) 2019 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
f2c1f0d4 | 4 | * |
ab5be9fa | 5 | * SPDX-License-Identifier: LGPL-2.1-only |
f2c1f0d4 | 6 | * |
f2c1f0d4 MD |
7 | */ |
8 | ||
9 | #define _LGPL_SOURCE | |
f2c1f0d4 MD |
10 | #include <string.h> |
11 | ||
12 | #include <lttng/lttng-error.h> | |
13 | #include <lttng/clear.h> | |
14 | #include <lttng/clear-handle.h> | |
15 | #include <common/sessiond-comm/sessiond-comm.h> | |
16 | #include <common/macros.h> | |
17 | #include <common/compat/poll.h> | |
18 | #include <common/dynamic-buffer.h> | |
19 | #include <common/buffer-view.h> | |
20 | #include <common/optional.h> | |
21 | ||
22 | #include "lttng-ctl-helper.h" | |
23 | ||
24 | enum communication_state { | |
25 | COMMUNICATION_STATE_RECEIVE_LTTNG_MSG, | |
26 | COMMUNICATION_STATE_RECEIVE_COMMAND_HEADER, | |
27 | COMMUNICATION_STATE_END, | |
28 | COMMUNICATION_STATE_ERROR, | |
29 | }; | |
30 | ||
31 | struct lttng_clear_handle { | |
32 | LTTNG_OPTIONAL(enum lttng_error_code) clear_return_code; | |
33 | struct { | |
34 | int socket; | |
35 | struct lttng_poll_event events; | |
36 | size_t bytes_left_to_receive; | |
37 | enum communication_state state; | |
38 | struct lttng_dynamic_buffer buffer; | |
39 | LTTNG_OPTIONAL(size_t) data_size; | |
40 | } communication; | |
41 | }; | |
42 | ||
43 | void lttng_clear_handle_destroy(struct lttng_clear_handle *handle) | |
44 | { | |
45 | int ret; | |
46 | ||
47 | if (!handle) { | |
48 | return; | |
49 | } | |
50 | ||
51 | if (handle->communication.socket >= 0) { | |
52 | ret = close(handle->communication.socket); | |
53 | if (ret) { | |
54 | PERROR("Failed to close lttng-sessiond command socket"); | |
55 | } | |
e429da85 JG |
56 | } |
57 | lttng_poll_clean(&handle->communication.events); | |
f2c1f0d4 MD |
58 | lttng_dynamic_buffer_reset(&handle->communication.buffer); |
59 | free(handle); | |
60 | } | |
61 | ||
62 | static | |
63 | struct lttng_clear_handle *lttng_clear_handle_create(int sessiond_socket) | |
64 | { | |
65 | int ret; | |
66 | struct lttng_clear_handle *handle = zmalloc(sizeof(*handle)); | |
67 | ||
68 | if (!handle) { | |
69 | goto end; | |
70 | } | |
71 | lttng_dynamic_buffer_init(&handle->communication.buffer); | |
72 | handle->communication.socket = sessiond_socket; | |
73 | ret = lttng_poll_create(&handle->communication.events, 1, 0); | |
74 | if (ret) { | |
75 | goto error; | |
76 | } | |
77 | ||
78 | ret = lttng_poll_add(&handle->communication.events, sessiond_socket, | |
79 | LPOLLIN | LPOLLHUP | LPOLLRDHUP | LPOLLERR); | |
e429da85 | 80 | if (ret) { |
f2c1f0d4 | 81 | goto error; |
e429da85 | 82 | } |
f2c1f0d4 MD |
83 | |
84 | handle->communication.bytes_left_to_receive = | |
85 | sizeof(struct lttcomm_lttng_msg); | |
86 | handle->communication.state = COMMUNICATION_STATE_RECEIVE_LTTNG_MSG; | |
87 | end: | |
88 | return handle; | |
89 | error: | |
90 | lttng_clear_handle_destroy(handle); | |
91 | return NULL; | |
92 | } | |
93 | ||
94 | static | |
95 | int handle_state_transition(struct lttng_clear_handle *handle) | |
96 | { | |
97 | int ret = 0; | |
98 | ||
a0377dfe | 99 | LTTNG_ASSERT(handle->communication.bytes_left_to_receive == 0); |
f2c1f0d4 MD |
100 | |
101 | switch (handle->communication.state) { | |
102 | case COMMUNICATION_STATE_RECEIVE_LTTNG_MSG: | |
103 | { | |
104 | const struct lttcomm_lttng_msg *msg = | |
105 | (typeof(msg)) handle->communication.buffer.data; | |
106 | ||
107 | LTTNG_OPTIONAL_SET(&handle->clear_return_code, | |
108 | (enum lttng_error_code) msg->ret_code); | |
109 | if (handle->clear_return_code.value != LTTNG_OK) { | |
110 | handle->communication.state = COMMUNICATION_STATE_END; | |
111 | break; | |
112 | } else if (msg->cmd_header_size != 0 || msg->data_size != 0) { | |
113 | handle->communication.state = COMMUNICATION_STATE_ERROR; | |
114 | ret = -1; | |
115 | break; | |
116 | } | |
117 | ||
118 | handle->communication.state = COMMUNICATION_STATE_END; | |
119 | handle->communication.bytes_left_to_receive = 0; | |
120 | LTTNG_OPTIONAL_SET(&handle->communication.data_size, 0); | |
121 | ret = lttng_dynamic_buffer_set_size( | |
122 | &handle->communication.buffer, 0); | |
a0377dfe | 123 | LTTNG_ASSERT(!ret); |
f2c1f0d4 MD |
124 | break; |
125 | } | |
126 | default: | |
127 | abort(); | |
128 | } | |
129 | ||
130 | /* Clear reception buffer on state transition. */ | |
131 | if (lttng_dynamic_buffer_set_size(&handle->communication.buffer, 0)) { | |
132 | abort(); | |
133 | } | |
134 | return ret; | |
135 | } | |
136 | ||
137 | static | |
138 | int handle_incoming_data(struct lttng_clear_handle *handle) | |
139 | { | |
140 | int ret; | |
141 | ssize_t comm_ret; | |
142 | const size_t original_buffer_size = handle->communication.buffer.size; | |
143 | ||
144 | /* Reserve space for reception. */ | |
145 | ret = lttng_dynamic_buffer_set_size(&handle->communication.buffer, | |
146 | original_buffer_size + handle->communication.bytes_left_to_receive); | |
147 | if (ret) { | |
148 | goto end; | |
149 | } | |
150 | ||
151 | comm_ret = lttcomm_recv_unix_sock(handle->communication.socket, | |
152 | handle->communication.buffer.data + original_buffer_size, | |
153 | handle->communication.bytes_left_to_receive); | |
154 | if (comm_ret <= 0) { | |
155 | ret = -1; | |
156 | goto end; | |
157 | } | |
158 | ||
159 | handle->communication.bytes_left_to_receive -= comm_ret; | |
160 | if (handle->communication.bytes_left_to_receive == 0) { | |
161 | ret = handle_state_transition(handle); | |
162 | } else { | |
163 | ret = lttng_dynamic_buffer_set_size( | |
164 | &handle->communication.buffer, | |
165 | original_buffer_size + comm_ret); | |
166 | } | |
167 | end: | |
168 | return ret; | |
169 | } | |
170 | ||
171 | extern enum lttng_clear_handle_status | |
172 | lttng_clear_handle_wait_for_completion( | |
173 | struct lttng_clear_handle *handle, int timeout_ms) | |
174 | { | |
f2c1f0d4 MD |
175 | enum lttng_clear_handle_status status; |
176 | unsigned long time_left_ms = 0; | |
177 | const bool has_timeout = timeout_ms > 0; | |
178 | struct timespec initial_time; | |
179 | ||
e429da85 | 180 | if (handle->communication.state == COMMUNICATION_STATE_ERROR) { |
f2c1f0d4 MD |
181 | status = LTTNG_CLEAR_HANDLE_STATUS_ERROR; |
182 | goto end; | |
183 | } else if (handle->communication.state == COMMUNICATION_STATE_END) { | |
184 | status = LTTNG_CLEAR_HANDLE_STATUS_COMPLETED; | |
185 | goto end; | |
186 | } | |
e429da85 | 187 | if (has_timeout) { |
bf3683d0 | 188 | int ret = lttng_clock_gettime(CLOCK_MONOTONIC, &initial_time); |
f2c1f0d4 MD |
189 | if (ret) { |
190 | status = LTTNG_CLEAR_HANDLE_STATUS_ERROR; | |
191 | goto end; | |
192 | } | |
193 | time_left_ms = (unsigned long) timeout_ms; | |
e429da85 | 194 | } |
f2c1f0d4 | 195 | |
e429da85 | 196 | while (handle->communication.state != COMMUNICATION_STATE_END && |
f2c1f0d4 MD |
197 | (time_left_ms || !has_timeout)) { |
198 | int ret; | |
199 | uint32_t revents; | |
e429da85 | 200 | struct timespec current_time, diff; |
f2c1f0d4 MD |
201 | unsigned long diff_ms; |
202 | ||
e429da85 | 203 | ret = lttng_poll_wait(&handle->communication.events, |
f2c1f0d4 | 204 | has_timeout ? time_left_ms : -1); |
e429da85 | 205 | if (ret == 0) { |
f2c1f0d4 MD |
206 | /* timeout */ |
207 | break; | |
208 | } else if (ret < 0) { | |
209 | status = LTTNG_CLEAR_HANDLE_STATUS_ERROR; | |
210 | goto end; | |
211 | } | |
212 | ||
213 | /* The sessiond connection socket is the only monitored fd. */ | |
214 | revents = LTTNG_POLL_GETEV(&handle->communication.events, 0); | |
215 | if (revents & LPOLLIN) { | |
216 | ret = handle_incoming_data(handle); | |
217 | if (ret) { | |
218 | handle->communication.state = | |
219 | COMMUNICATION_STATE_ERROR; | |
220 | status = LTTNG_CLEAR_HANDLE_STATUS_ERROR; | |
221 | goto end; | |
222 | } | |
223 | } else { | |
224 | handle->communication.state = COMMUNICATION_STATE_ERROR; | |
225 | status = LTTNG_CLEAR_HANDLE_STATUS_ERROR; | |
226 | goto end; | |
227 | } | |
228 | if (!has_timeout) { | |
229 | continue; | |
230 | } | |
231 | ||
232 | ret = lttng_clock_gettime(CLOCK_MONOTONIC, ¤t_time); | |
233 | if (ret) { | |
234 | status = LTTNG_CLEAR_HANDLE_STATUS_ERROR; | |
235 | goto end; | |
236 | } | |
237 | diff = timespec_abs_diff(initial_time, current_time); | |
238 | ret = timespec_to_ms(diff, &diff_ms); | |
239 | if (ret) { | |
240 | ERR("Failed to compute elapsed time while waiting for completion"); | |
241 | status = LTTNG_CLEAR_HANDLE_STATUS_ERROR; | |
242 | goto end; | |
243 | } | |
244 | DBG("%lums elapsed while waiting for session clear completion", | |
245 | diff_ms); | |
246 | diff_ms = max_t(unsigned long, diff_ms, 1); | |
247 | diff_ms = min_t(unsigned long, diff_ms, time_left_ms); | |
248 | time_left_ms -= diff_ms; | |
249 | } | |
250 | ||
251 | status = handle->communication.state == COMMUNICATION_STATE_END ? | |
252 | LTTNG_CLEAR_HANDLE_STATUS_COMPLETED : | |
253 | LTTNG_CLEAR_HANDLE_STATUS_TIMEOUT; | |
254 | end: | |
255 | return status; | |
256 | } | |
257 | ||
258 | extern enum lttng_clear_handle_status | |
259 | lttng_clear_handle_get_result( | |
260 | const struct lttng_clear_handle *handle, | |
261 | enum lttng_error_code *result) | |
262 | { | |
263 | enum lttng_clear_handle_status status = | |
264 | LTTNG_CLEAR_HANDLE_STATUS_OK; | |
265 | ||
266 | if (!handle->clear_return_code.is_set) { | |
267 | status = LTTNG_CLEAR_HANDLE_STATUS_INVALID; | |
268 | goto end; | |
269 | } | |
270 | *result = handle->clear_return_code.value; | |
271 | end: | |
272 | return status; | |
273 | } | |
274 | ||
275 | /* | |
276 | * Clear the session | |
277 | */ | |
278 | enum lttng_error_code lttng_clear_session(const char *session_name, | |
279 | struct lttng_clear_handle **_handle) | |
280 | { | |
281 | enum lttng_error_code ret_code = LTTNG_OK; | |
282 | struct lttng_clear_handle *handle = NULL; | |
283 | struct lttcomm_session_msg lsm = { | |
284 | .cmd_type = LTTNG_CLEAR_SESSION, | |
285 | }; | |
286 | int sessiond_socket = -1; | |
287 | ssize_t comm_ret; | |
288 | int ret; | |
289 | ||
290 | if (session_name == NULL) { | |
291 | ret_code = LTTNG_ERR_INVALID; | |
292 | goto error; | |
293 | } | |
294 | ret = lttng_strncpy(lsm.session.name, session_name, | |
295 | sizeof(lsm.session.name)); | |
296 | if (ret) { | |
297 | ret_code = LTTNG_ERR_INVALID; | |
298 | goto error; | |
299 | } | |
300 | ret = connect_sessiond(); | |
301 | if (ret < 0) { | |
302 | ret_code = LTTNG_ERR_NO_SESSIOND; | |
303 | goto error; | |
304 | } else { | |
305 | sessiond_socket = ret; | |
306 | } | |
307 | handle = lttng_clear_handle_create(sessiond_socket); | |
308 | if (!handle) { | |
309 | ret_code = LTTNG_ERR_NOMEM; | |
310 | goto error; | |
311 | } | |
312 | comm_ret = lttcomm_send_creds_unix_sock(sessiond_socket, &lsm, sizeof(lsm)); | |
313 | if (comm_ret < 0) { | |
314 | ret_code = LTTNG_ERR_FATAL; | |
315 | goto error; | |
316 | } | |
317 | sessiond_socket = -1; | |
318 | ||
319 | error: | |
320 | /* Transfer the handle to the caller. */ | |
321 | if (_handle) { | |
322 | *_handle = handle; | |
323 | handle = NULL; | |
324 | } | |
325 | if (sessiond_socket >= 0) { | |
326 | ret = close(sessiond_socket); | |
327 | if (ret < 0) { | |
328 | PERROR("Failed to close the LTTng session daemon connection socket"); | |
329 | } | |
330 | } | |
331 | if (handle) { | |
332 | lttng_clear_handle_destroy(handle); | |
333 | } | |
334 | return ret_code; | |
335 | } |