Fix: sessiond: unchecked return value
[lttng-tools.git] / src / bin / lttng-relayd / viewer-stream.c
CommitLineData
2f8f53af 1/*
ab5be9fa
MJ
2 * Copyright (C) 2013 Julien Desfossez <jdesfossez@efficios.com>
3 * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
4 * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
2f8f53af 5 *
ab5be9fa 6 * SPDX-License-Identifier: GPL-2.0-only
2f8f53af 7 *
2f8f53af
DG
8 */
9
6c1c0768 10#define _LGPL_SOURCE
2f8f53af
DG
11#include <common/common.h>
12#include <common/index/index.h>
f5436bfc 13#include <common/compat/string.h>
b0d240a2
MD
14#include <common/utils.h>
15#include <sys/types.h>
16#include <sys/stat.h>
17#include <fcntl.h>
2f8f53af
DG
18
19#include "lttng-relayd.h"
20#include "viewer-stream.h"
21
7591bab1 22static void viewer_stream_destroy(struct relay_viewer_stream *vstream)
2f8f53af 23{
7591bab1
MD
24 free(vstream->path_name);
25 free(vstream->channel_name);
26 free(vstream);
2f8f53af
DG
27}
28
7591bab1 29static void viewer_stream_destroy_rcu(struct rcu_head *head)
2f8f53af 30{
7591bab1 31 struct relay_viewer_stream *vstream =
2f8f53af
DG
32 caa_container_of(head, struct relay_viewer_stream, rcu_node);
33
7591bab1 34 viewer_stream_destroy(vstream);
2f8f53af
DG
35}
36
37struct relay_viewer_stream *viewer_stream_create(struct relay_stream *stream,
b66a15d1 38 struct lttng_trace_chunk *viewer_trace_chunk,
7591bab1 39 enum lttng_viewer_seek seek_t)
2f8f53af 40{
ebb29c10
JG
41 struct relay_viewer_stream *vstream = NULL;
42 const bool acquired_reference = lttng_trace_chunk_get(
b66a15d1 43 viewer_trace_chunk);
ebb29c10
JG
44
45 if (!acquired_reference) {
46 goto error;
47 }
2f8f53af 48
2f8f53af
DG
49 vstream = zmalloc(sizeof(*vstream));
50 if (!vstream) {
51 PERROR("relay viewer stream zmalloc");
52 goto error;
53 }
54
b66a15d1
JG
55 vstream->stream_file.trace_chunk = viewer_trace_chunk;
56 viewer_trace_chunk = NULL;
f5436bfc 57 vstream->path_name = lttng_strndup(stream->path_name, LTTNG_VIEWER_PATH_MAX);
b272577e
MD
58 if (vstream->path_name == NULL) {
59 PERROR("relay viewer path_name alloc");
60 goto error;
61 }
f5436bfc 62 vstream->channel_name = lttng_strndup(stream->channel_name,
2f8f53af 63 LTTNG_VIEWER_NAME_MAX);
b272577e
MD
64 if (vstream->channel_name == NULL) {
65 PERROR("relay viewer channel_name alloc");
66 goto error;
67 }
2f8f53af 68
a44ca2ca
MD
69 if (!stream_get(stream)) {
70 ERR("Cannot get stream");
71 goto error;
72 }
73 vstream->stream = stream;
74
75 pthread_mutex_lock(&stream->lock);
76
77 if (stream->is_metadata && stream->trace->viewer_metadata_stream) {
78 ERR("Cannot attach viewer metadata stream to trace (busy).");
79 goto error_unlock;
80 }
81
2f8f53af 82 switch (seek_t) {
c4e361a4 83 case LTTNG_VIEWER_SEEK_BEGINNING:
a44ca2ca
MD
84 {
85 uint64_t seq_tail = tracefile_array_get_seq_tail(stream->tfa);
86
87 if (seq_tail == -1ULL) {
88 /*
89 * Tail may not be initialized yet. Nonetheless, we know
90 * we want to send the first index once it becomes
91 * available.
92 */
93 seq_tail = 0;
94 }
95 vstream->current_tracefile_id =
96 tracefile_array_get_file_index_tail(stream->tfa);
97 vstream->index_sent_seqcount = seq_tail;
2f8f53af 98 break;
a44ca2ca 99 }
c4e361a4 100 case LTTNG_VIEWER_SEEK_LAST:
a44ca2ca 101 vstream->current_tracefile_id =
78118e3b 102 tracefile_array_get_read_file_index_head(stream->tfa);
a44ca2ca
MD
103 /*
104 * We seek at the very end of each stream, awaiting for
105 * a future packet to eventually come in.
106 *
107 * We don't need to check the head position for -1ULL since the
108 * increment will set it to 0.
109 */
110 vstream->index_sent_seqcount =
111 tracefile_array_get_seq_head(stream->tfa) + 1;
2f8f53af
DG
112 break;
113 default:
a44ca2ca 114 goto error_unlock;
2f8f53af 115 }
2f8f53af 116
2f8f53af 117 /*
a44ca2ca
MD
118 * If we never received an index for the current stream, delay
119 * the opening of the index, otherwise open it right now.
2f8f53af 120 */
b0d240a2 121 if (stream->index_file == NULL) {
f8f3885c 122 vstream->index_file = NULL;
2f8f53af 123 } else {
ebb29c10
JG
124 const uint32_t connection_major = stream->trace->session->major;
125 const uint32_t connection_minor = stream->trace->session->minor;
3ff5c5db 126 enum lttng_trace_chunk_status chunk_status;
ebb29c10 127
3ff5c5db 128 chunk_status = lttng_index_file_create_from_trace_chunk_read_only(
b66a15d1
JG
129 vstream->stream_file.trace_chunk,
130 stream->path_name,
ebb29c10
JG
131 stream->channel_name, stream->tracefile_size,
132 vstream->current_tracefile_id,
133 lttng_to_index_major(connection_major,
134 connection_minor),
135 lttng_to_index_minor(connection_major,
3ff5c5db
MD
136 connection_minor),
137 true, &vstream->index_file);
138 if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
139 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_NO_FILE) {
140 vstream->index_file = NULL;
141 } else {
142 goto error_unlock;
143 }
2f8f53af 144 }
2f8f53af
DG
145 }
146
b0d240a2
MD
147 /*
148 * If we never received a data file for the current stream, delay the
149 * opening, otherwise open it right now.
150 */
8bb66c3c
JG
151 if (stream->file) {
152 int ret;
b0d240a2
MD
153 char file_path[LTTNG_PATH_MAX];
154 enum lttng_trace_chunk_status status;
155
156 ret = utils_stream_file_path(stream->path_name,
157 stream->channel_name, stream->tracefile_size,
158 vstream->current_tracefile_id, NULL, file_path,
159 sizeof(file_path));
160 if (ret < 0) {
161 goto error_unlock;
162 }
163
8bb66c3c
JG
164 status = lttng_trace_chunk_open_fs_handle(
165 vstream->stream_file.trace_chunk, file_path,
166 O_RDONLY, 0, &vstream->stream_file.handle,
167 true);
b0d240a2
MD
168 if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
169 goto error_unlock;
170 }
b0d240a2
MD
171 }
172
f8f3885c 173 if (seek_t == LTTNG_VIEWER_SEEK_LAST && vstream->index_file) {
2f8f53af
DG
174 off_t lseek_ret;
175
8bb66c3c
JG
176 lseek_ret = fs_handle_seek(
177 vstream->index_file->file, 0, SEEK_END);
2f8f53af 178 if (lseek_ret < 0) {
7591bab1 179 goto error_unlock;
2f8f53af 180 }
7591bab1 181 }
7591bab1
MD
182 if (stream->is_metadata) {
183 rcu_assign_pointer(stream->trace->viewer_metadata_stream,
184 vstream);
2f8f53af 185 }
a44ca2ca 186 pthread_mutex_unlock(&stream->lock);
2f8f53af 187
7591bab1
MD
188 /* Globally visible after the add unique. */
189 lttng_ht_node_init_u64(&vstream->stream_n, stream->stream_handle);
7591bab1 190 urcu_ref_init(&vstream->ref);
c51b2177 191 lttng_ht_add_unique_u64(viewer_streams_ht, &vstream->stream_n);
7591bab1 192
2f8f53af
DG
193 return vstream;
194
7591bab1
MD
195error_unlock:
196 pthread_mutex_unlock(&stream->lock);
2f8f53af
DG
197error:
198 if (vstream) {
7591bab1 199 viewer_stream_destroy(vstream);
2f8f53af 200 }
e4650a96 201 if (viewer_trace_chunk && acquired_reference) {
b66a15d1
JG
202 lttng_trace_chunk_put(viewer_trace_chunk);
203 }
2f8f53af
DG
204 return NULL;
205}
206
7591bab1 207static void viewer_stream_unpublish(struct relay_viewer_stream *vstream)
2f8f53af
DG
208{
209 int ret;
210 struct lttng_ht_iter iter;
211
7591bab1 212 iter.iter.node = &vstream->stream_n.node;
2f8f53af
DG
213 ret = lttng_ht_del(viewer_streams_ht, &iter);
214 assert(!ret);
215}
216
7591bab1 217static void viewer_stream_release(struct urcu_ref *ref)
2f8f53af 218{
7591bab1
MD
219 struct relay_viewer_stream *vstream = caa_container_of(ref,
220 struct relay_viewer_stream, ref);
2a174661 221
7591bab1
MD
222 if (vstream->stream->is_metadata) {
223 rcu_assign_pointer(vstream->stream->trace->viewer_metadata_stream, NULL);
2a174661 224 }
2f8f53af 225
7591bab1
MD
226 viewer_stream_unpublish(vstream);
227
8bb66c3c
JG
228 if (vstream->stream_file.handle) {
229 fs_handle_close(vstream->stream_file.handle);
230 vstream->stream_file.handle = NULL;
2f8f53af 231 }
f8f3885c
MD
232 if (vstream->index_file) {
233 lttng_index_file_put(vstream->index_file);
234 vstream->index_file = NULL;
7591bab1
MD
235 }
236 if (vstream->stream) {
237 stream_put(vstream->stream);
238 vstream->stream = NULL;
239 }
4c2717fc
JG
240 lttng_trace_chunk_put(vstream->stream_file.trace_chunk);
241 vstream->stream_file.trace_chunk = NULL;
7591bab1
MD
242 call_rcu(&vstream->rcu_node, viewer_stream_destroy_rcu);
243}
244
245/* Must be called with RCU read-side lock held. */
246bool viewer_stream_get(struct relay_viewer_stream *vstream)
247{
ce4d4083 248 return urcu_ref_get_unless_zero(&vstream->ref);
2f8f53af
DG
249}
250
251/*
7591bab1 252 * Get viewer stream by id.
2f8f53af 253 *
7591bab1 254 * Return viewer stream if found else NULL.
2f8f53af 255 */
7591bab1 256struct relay_viewer_stream *viewer_stream_get_by_id(uint64_t id)
2f8f53af
DG
257{
258 struct lttng_ht_node_u64 *node;
259 struct lttng_ht_iter iter;
7591bab1 260 struct relay_viewer_stream *vstream = NULL;
2f8f53af 261
7591bab1 262 rcu_read_lock();
2f8f53af
DG
263 lttng_ht_lookup(viewer_streams_ht, &id, &iter);
264 node = lttng_ht_iter_get_node_u64(&iter);
265 if (!node) {
266 DBG("Relay viewer stream %" PRIu64 " not found", id);
267 goto end;
268 }
7591bab1
MD
269 vstream = caa_container_of(node, struct relay_viewer_stream, stream_n);
270 if (!viewer_stream_get(vstream)) {
271 vstream = NULL;
272 }
2f8f53af 273end:
7591bab1
MD
274 rcu_read_unlock();
275 return vstream;
276}
277
278void viewer_stream_put(struct relay_viewer_stream *vstream)
279{
280 rcu_read_lock();
7591bab1 281 urcu_ref_put(&vstream->ref, viewer_stream_release);
7591bab1
MD
282 rcu_read_unlock();
283}
284
3087b021
MD
285void viewer_stream_close_files(struct relay_viewer_stream *vstream)
286{
287 if (vstream->index_file) {
288 lttng_index_file_put(vstream->index_file);
289 vstream->index_file = NULL;
290 }
8bb66c3c
JG
291 if (vstream->stream_file.handle) {
292 fs_handle_close(vstream->stream_file.handle);
293 vstream->stream_file.handle = NULL;
3087b021
MD
294 }
295}
296
297void viewer_stream_sync_tracefile_array_tail(struct relay_viewer_stream *vstream)
298{
299 const struct relay_stream *stream = vstream->stream;
300 uint64_t seq_tail;
301
302 vstream->current_tracefile_id = tracefile_array_get_file_index_tail(stream->tfa);
303 seq_tail = tracefile_array_get_seq_tail(stream->tfa);
304 if (seq_tail == -1ULL) {
305 seq_tail = 0;
306 }
307 vstream->index_sent_seqcount = seq_tail;
308}
309
2f8f53af
DG
310/*
311 * Rotate a stream to the next tracefile.
312 *
7591bab1 313 * Must be called with the rstream lock held.
b0d240a2 314 * Returns 0 on success, 1 on EOF.
2f8f53af 315 */
7591bab1 316int viewer_stream_rotate(struct relay_viewer_stream *vstream)
2f8f53af
DG
317{
318 int ret;
a44ca2ca 319 uint64_t new_id;
ebb29c10 320 const struct relay_stream *stream = vstream->stream;
2f8f53af 321
7591bab1 322 /* Detect the last tracefile to open. */
a44ca2ca
MD
323 if (stream->index_received_seqcount
324 == vstream->index_sent_seqcount
7591bab1
MD
325 && stream->trace->session->connection_closed) {
326 ret = 1;
2a174661
DG
327 goto end;
328 }
2f8f53af 329
7591bab1
MD
330 if (stream->tracefile_count == 0) {
331 /* Ignore rotation, there is none to do. */
332 ret = 0;
2f8f53af
DG
333 goto end;
334 }
335
a44ca2ca
MD
336 /*
337 * Try to move to the next file.
338 */
339 new_id = (vstream->current_tracefile_id + 1)
340 % stream->tracefile_count;
341 if (tracefile_array_seq_in_file(stream->tfa, new_id,
342 vstream->index_sent_seqcount)) {
343 vstream->current_tracefile_id = new_id;
2f8f53af 344 } else {
a44ca2ca
MD
345 uint64_t seq_tail = tracefile_array_get_seq_tail(stream->tfa);
346
347 /*
348 * This can only be reached on overwrite, which implies there
349 * has been data written at some point, which will have set the
350 * tail.
351 */
352 assert(seq_tail != -1ULL);
353 /*
354 * We need to resync because we lag behind tail.
355 */
7591bab1 356 vstream->current_tracefile_id =
a44ca2ca
MD
357 tracefile_array_get_file_index_tail(stream->tfa);
358 vstream->index_sent_seqcount = seq_tail;
2f8f53af 359 }
b0d240a2
MD
360 viewer_stream_close_files(vstream);
361 ret = 0;
2f8f53af 362end:
2f8f53af
DG
363 return ret;
364}
7591bab1
MD
365
366void print_viewer_streams(void)
367{
368 struct lttng_ht_iter iter;
369 struct relay_viewer_stream *vstream;
370
ce3f3ba3
JG
371 if (!viewer_streams_ht) {
372 return;
373 }
374
7591bab1
MD
375 rcu_read_lock();
376 cds_lfht_for_each_entry(viewer_streams_ht->ht, &iter.iter, vstream,
377 stream_n.node) {
378 if (!viewer_stream_get(vstream)) {
379 continue;
380 }
381 DBG("vstream %p refcount %ld stream %" PRIu64 " trace %" PRIu64
382 " session %" PRIu64,
383 vstream,
384 vstream->ref.refcount,
385 vstream->stream->stream_handle,
386 vstream->stream->trace->id,
387 vstream->stream->trace->session->id);
388 viewer_stream_put(vstream);
389 }
390 rcu_read_unlock();
391}
This page took 0.095091 seconds and 4 git commands to generate.