formats/lttng-live/lttng-live-comm.c

   1 /*
   2  * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
   3  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy
   6  * of this software and associated documentation files (the "Software"), to deal
   7  * in the Software without restriction, including without limitation the rights
   8  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   9  * copies of the Software, and to permit persons to whom the Software is
  10  * furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in
  13  * all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  */
  23
  24 #include <sys/socket.h>
  25 #include <sys/types.h>
  26 #include <netinet/in.h>
  27 #include <netdb.h>
  28 #include <stdio.h>
  29 #include <string.h>
  30 #include <stdlib.h>
  31 #include <unistd.h>
  32 #include <errno.h>
  33 #include <inttypes.h>
  34 #include <fcntl.h>
  35 #include <sys/mman.h>
  36
  37 #include <babeltrace/ctf/ctf-index.h>
  38
  39 #include <babeltrace/babeltrace.h>
  40 #include <babeltrace/ctf/events.h>
  41 #include <babeltrace/ctf/callbacks.h>
  42 #include <babeltrace/ctf/iterator.h>
  43
  44 /* for packet_index */
  45 #include <babeltrace/ctf/types.h>
  46
  47 #include <babeltrace/ctf/metadata.h>
  48 #include <babeltrace/ctf-text/types.h>
  49 #include <babeltrace/ctf/events-internal.h>
  50 #include <formats/ctf/events-private.h>
  51
  52 #include "lttng-live.h"
  53 #include "lttng-viewer-abi.h"
  54
  55 /*
  56  * Memory allocation zeroed
  57  */
  58 #define zmalloc(x) calloc(1, x)
  59
  60 #ifndef max_t
  61 #define max_t(type, a, b)       \
  62         ((type) (a) > (type) (b) ? (type) (a) : (type) (b))
  63 #endif
  64
  65 static void ctf_live_packet_seek(struct bt_stream_pos *stream_pos,
  66                 size_t index, int whence);
  67 static void add_traces(gpointer key, gpointer value, gpointer user_data);
  68 static int del_traces(gpointer key, gpointer value, gpointer user_data);
  69 static int get_new_metadata(struct lttng_live_ctx *ctx,
  70                 struct lttng_live_viewer_stream *viewer_stream);
  71
  72 int lttng_live_connect_viewer(struct lttng_live_ctx *ctx)
  73 {
  74         struct hostent *host;
  75         struct sockaddr_in server_addr;
  76         int ret;
  77
  78         host = gethostbyname(ctx->relay_hostname);
  79         if (!host) {
  80                 ret = -1;
  81                 goto end;
  82         }
  83
  84         if ((ctx->control_sock = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
  85                 perror("Socket");
  86                 ret = -1;
  87                 goto end;
  88         }
  89
  90         server_addr.sin_family = AF_INET;
  91         server_addr.sin_port = htons(ctx->port);
  92         server_addr.sin_addr = *((struct in_addr *) host->h_addr);
  93         bzero(&(server_addr.sin_zero), 8);
  94
  95         if (connect(ctx->control_sock, (struct sockaddr *) &server_addr,
  96                                 sizeof(struct sockaddr)) == -1) {
  97                 perror("Connect");
  98                 ret = -1;
  99                 goto end;
 100         }
 101
 102         ret = 0;
 103
 104 end:
 105         return ret;
 106 }
 107
 108 int lttng_live_establish_connection(struct lttng_live_ctx *ctx)
 109 {
 110         struct lttng_viewer_cmd cmd;
 111         struct lttng_viewer_connect connect;
 112         int ret;
 113         ssize_t ret_len;
 114
 115         cmd.cmd = htobe32(LTTNG_VIEWER_CONNECT);
 116         cmd.data_size = sizeof(connect);
 117         cmd.cmd_version = 0;
 118
 119         connect.viewer_session_id = -1ULL;      /* will be set on recv */
 120         connect.major = htobe32(LTTNG_LIVE_MAJOR);
 121         connect.minor = htobe32(LTTNG_LIVE_MINOR);
 122         connect.type = htobe32(LTTNG_VIEWER_CLIENT_COMMAND);
 123
 124         do {
 125                 ret_len = send(ctx->control_sock, &cmd, sizeof(cmd), 0);
 126         } while (ret_len < 0 && errno == EINTR);
 127         if (ret_len < 0) {
 128                 perror("[error] Error sending cmd");
 129                 ret = ret_len;
 130                 goto error;
 131         }
 132         assert(ret_len == sizeof(cmd));
 133
 134         do {
 135                 ret_len = send(ctx->control_sock, &connect, sizeof(connect), 0);
 136         } while (ret_len < 0 && errno == EINTR);
 137         if (ret_len < 0) {
 138                 perror("[error] Error sending version");
 139                 ret = ret_len;
 140                 goto error;
 141         }
 142         assert(ret_len == sizeof(connect));
 143
 144         do {
 145                 ret_len = recv(ctx->control_sock, &connect, sizeof(connect), 0);
 146         } while (ret_len < 0 && errno == EINTR);
 147         if (ret_len == 0) {
 148                 fprintf(stderr, "[error] Remote side has closed connection\n");
 149                 ret = -1;
 150                 goto error;
 151         }
 152         if (ret_len < 0) {
 153                 perror("[error] Error receiving version");
 154                 ret = ret_len;
 155                 goto error;
 156         }
 157         assert(ret_len == sizeof(connect));
 158
 159         printf_verbose("Received viewer session ID : %" PRIu64 "\n",
 160                         be64toh(connect.viewer_session_id));
 161         printf_verbose("Relayd version : %u.%u\n", be32toh(connect.major),
 162                         be32toh(connect.minor));
 163
 164         ret = 0;
 165
 166 error:
 167         return ret;
 168 }
 169
 170 static
 171 void free_session_list(GPtrArray *session_list)
 172 {
 173         int i;
 174         struct lttng_live_relay_session *relay_session;
 175
 176         for (i = 0; i < session_list->len; i++) {
 177                 relay_session = g_ptr_array_index(session_list, i);
 178                 free(relay_session->name);
 179                 free(relay_session->hostname);
 180         }
 181         g_ptr_array_free(session_list, TRUE);
 182 }
 183
 184 static
 185 void print_session_list(GPtrArray *session_list, const char *path)
 186 {
 187         int i;
 188         struct lttng_live_relay_session *relay_session;
 189
 190         for (i = 0; i < session_list->len; i++) {
 191                 relay_session = g_ptr_array_index(session_list, i);
 192                 fprintf(stdout, "%s/host/%s/%s (timer = %u, "
 193                                 "%u stream(s), %u client(s) connected)\n",
 194                                 path, relay_session->hostname,
 195                                 relay_session->name, relay_session->timer,
 196                                 relay_session->streams, relay_session->clients);
 197         }
 198 }
 199
 200 static
 201 void update_session_list(GPtrArray *session_list, char *hostname,
 202                 char *session_name, uint32_t streams, uint32_t clients,
 203                 uint32_t timer)
 204 {
 205         int i, found = 0;
 206         struct lttng_live_relay_session *relay_session;
 207
 208         for (i = 0; i < session_list->len; i++) {
 209                 relay_session = g_ptr_array_index(session_list, i);
 210                 if ((strncmp(relay_session->hostname, hostname, NAME_MAX) == 0) &&
 211                                 strncmp(relay_session->name,
 212                                         session_name, NAME_MAX) == 0) {
 213                         relay_session->streams += streams;
 214                         if (relay_session->clients < clients)
 215                                 relay_session->clients = clients;
 216                         found = 1;
 217                         break;
 218                 }
 219         }
 220         if (found)
 221                 return;
 222
 223         relay_session = g_new0(struct lttng_live_relay_session, 1);
 224         relay_session->hostname = strndup(hostname, NAME_MAX);
 225         relay_session->name = strndup(session_name, NAME_MAX);
 226         relay_session->clients = clients;
 227         relay_session->streams = streams;
 228         relay_session->timer = timer;
 229         g_ptr_array_add(session_list, relay_session);
 230 }
 231
 232 int lttng_live_list_sessions(struct lttng_live_ctx *ctx, const char *path)
 233 {
 234         struct lttng_viewer_cmd cmd;
 235         struct lttng_viewer_list_sessions list;
 236         struct lttng_viewer_session lsession;
 237         int i, ret, sessions_count, print_list = 0;
 238         ssize_t ret_len;
 239         uint64_t session_id;
 240         GPtrArray *session_list = NULL;
 241
 242         if (strlen(ctx->session_name) == 0) {
 243                 print_list = 1;
 244                 session_list = g_ptr_array_new();
 245         }
 246
 247         cmd.cmd = htobe32(LTTNG_VIEWER_LIST_SESSIONS);
 248         cmd.data_size = 0;
 249         cmd.cmd_version = 0;
 250
 251         do {
 252                 ret_len = send(ctx->control_sock, &cmd, sizeof(cmd), 0);
 253         } while (ret_len < 0 && errno == EINTR);
 254         if (ret_len < 0) {
 255                 perror("[error] Error sending cmd");
 256                 ret = ret_len;
 257                 goto error;
 258         }
 259         assert(ret_len == sizeof(cmd));
 260
 261         do {
 262                 ret_len = recv(ctx->control_sock, &list, sizeof(list), 0);
 263         } while (ret_len < 0 && errno == EINTR);
 264         if (ret_len == 0) {
 265                 fprintf(stderr, "[error] Remote side has closed connection\n");
 266                 ret = -1;
 267                 goto error;
 268         }
 269         if (ret_len < 0) {
 270                 perror("[error] Error receiving session list");
 271                 ret = ret_len;
 272                 goto error;
 273         }
 274         assert(ret_len == sizeof(list));
 275
 276         sessions_count = be32toh(list.sessions_count);
 277         for (i = 0; i < sessions_count; i++) {
 278                 do {
 279                         ret_len = recv(ctx->control_sock, &lsession, sizeof(lsession), 0);
 280                 } while (ret_len < 0 && errno == EINTR);
 281                 if (ret_len == 0) {
 282                         fprintf(stderr, "[error] Remote side has closed connection\n");
 283                         ret = -1;
 284                         goto error;
 285                 }
 286                 if (ret_len < 0) {
 287                         perror("[error] Error receiving session");
 288                         ret = ret_len;
 289                         goto error;
 290                 }
 291                 assert(ret_len == sizeof(lsession));
 292                 lsession.hostname[LTTNG_VIEWER_HOST_NAME_MAX - 1] = '\0';
 293                 lsession.session_name[LTTNG_VIEWER_NAME_MAX - 1] = '\0';
 294                 session_id = be64toh(lsession.id);
 295
 296                 if (print_list) {
 297                         update_session_list(session_list,
 298                                         lsession.hostname,
 299                                         lsession.session_name,
 300                                         be32toh(lsession.streams),
 301                                         be32toh(lsession.clients),
 302                                         be32toh(lsession.live_timer));
 303                 } else {
 304                         if ((strncmp(lsession.session_name, ctx->session_name,
 305                                 NAME_MAX) == 0) && (strncmp(lsession.hostname,
 306                                         ctx->traced_hostname, NAME_MAX) == 0)) {
 307                                 printf_verbose("Reading from session %" PRIu64 "\n",
 308                                                 session_id);
 309                                 g_array_append_val(ctx->session_ids,
 310                                                 session_id);
 311                         }
 312                 }
 313         }
 314
 315         if (print_list) {
 316                 print_session_list(session_list, path);
 317                 free_session_list(session_list);
 318         }
 319
 320         ret = 0;
 321
 322 error:
 323         return ret;
 324 }
 325
 326 int lttng_live_ctf_trace_assign(struct lttng_live_viewer_stream *stream,
 327                 uint64_t ctf_trace_id)
 328 {
 329         struct lttng_live_ctf_trace *trace;
 330         int ret = 0;
 331
 332         trace = g_hash_table_lookup(stream->session->ctf_traces,
 333                         (gpointer) ctf_trace_id);
 334         if (!trace) {
 335                 trace = g_new0(struct lttng_live_ctf_trace, 1);
 336                 trace->ctf_trace_id = ctf_trace_id;
 337                 trace->streams = g_ptr_array_new();
 338                 g_hash_table_insert(stream->session->ctf_traces,
 339                                 (gpointer) ctf_trace_id,
 340                                 trace);
 341         }
 342         if (stream->metadata_flag)
 343                 trace->metadata_stream = stream;
 344
 345         stream->ctf_trace = trace;
 346         g_ptr_array_add(trace->streams, stream);
 347
 348         return ret;
 349 }
 350
 351 int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id)
 352 {
 353         struct lttng_viewer_cmd cmd;
 354         struct lttng_viewer_attach_session_request rq;
 355         struct lttng_viewer_attach_session_response rp;
 356         struct lttng_viewer_stream stream;
 357         int ret, i;
 358         ssize_t ret_len;
 359
 360         cmd.cmd = htobe32(LTTNG_VIEWER_ATTACH_SESSION);
 361         cmd.data_size = sizeof(rq);
 362         cmd.cmd_version = 0;
 363
 364         memset(&rq, 0, sizeof(rq));
 365         rq.session_id = htobe64(id);
 366         // TODO: add cmd line parameter to select seek beginning
 367         // rq.seek = htobe32(LTTNG_VIEWER_SEEK_BEGINNING);
 368         rq.seek = htobe32(LTTNG_VIEWER_SEEK_LAST);
 369
 370         do {
 371                 ret_len = send(ctx->control_sock, &cmd, sizeof(cmd), 0);
 372         } while (ret_len < 0 && errno == EINTR);
 373         if (ret_len < 0) {
 374                 perror("[error] Error sending cmd");
 375                 ret = ret_len;
 376                 goto error;
 377         }
 378         assert(ret_len == sizeof(cmd));
 379
 380         do {
 381                 ret_len = send(ctx->control_sock, &rq, sizeof(rq), 0);
 382         } while (ret_len < 0 && errno == EINTR);
 383         if (ret_len < 0) {
 384                 perror("[error] Error sending attach request");
 385                 ret = ret_len;
 386                 goto error;
 387         }
 388         assert(ret_len == sizeof(rq));
 389
 390         do {
 391                 ret_len = recv(ctx->control_sock, &rp, sizeof(rp), 0);
 392         } while (ret_len < 0 && errno == EINTR);
 393         if (ret_len == 0) {
 394                 fprintf(stderr, "[error] Remote side has closed connection\n");
 395                 ret = -1;
 396                 goto error;
 397         }
 398         if (ret_len < 0) {
 399                 perror("[error] Error receiving attach response");
 400                 ret = ret_len;
 401                 goto error;
 402         }
 403         assert(ret_len == sizeof(rp));
 404
 405         switch(be32toh(rp.status)) {
 406         case LTTNG_VIEWER_ATTACH_OK:
 407                 break;
 408         case LTTNG_VIEWER_ATTACH_UNK:
 409                 ret = -LTTNG_VIEWER_ATTACH_UNK;
 410                 goto end;
 411         case LTTNG_VIEWER_ATTACH_ALREADY:
 412                 fprintf(stderr, "[error] There is already a viewer attached to this session\n");
 413                 ret = -1;
 414                 goto end;
 415         case LTTNG_VIEWER_ATTACH_NOT_LIVE:
 416                 fprintf(stderr, "[error] Not a live session\n");
 417                 ret = -1;
 418                 goto end;
 419         case LTTNG_VIEWER_ATTACH_SEEK_ERR:
 420                 fprintf(stderr, "[error] Wrong seek parameter\n");
 421                 ret = -1;
 422                 goto end;
 423         default:
 424                 fprintf(stderr, "[error] Unknown attach return code %u\n",
 425                                 be32toh(rp.status));
 426                 ret = -1;
 427                 goto end;
 428         }
 429         if (be32toh(rp.status) != LTTNG_VIEWER_ATTACH_OK) {
 430                 ret = -1;
 431                 goto end;
 432         }
 433
 434         ctx->session->stream_count += be32toh(rp.streams_count);
 435         /*
 436          * When the session is created but not started, we do an active wait
 437          * until it starts. It allows the viewer to start processing the trace
 438          * as soon as the session starts.
 439          */
 440         if (ctx->session->stream_count == 0) {
 441                 ret = 0;
 442                 goto end;
 443         }
 444         printf_verbose("Waiting for %" PRIu64 " streams:\n",
 445                 ctx->session->stream_count);
 446         ctx->session->streams = g_new0(struct lttng_live_viewer_stream,
 447                         ctx->session->stream_count);
 448         for (i = 0; i < be32toh(rp.streams_count); i++) {
 449                 do {
 450                         ret_len = recv(ctx->control_sock, &stream, sizeof(stream), 0);
 451                 } while (ret_len < 0 && errno == EINTR);
 452                 if (ret_len == 0) {
 453                         fprintf(stderr, "[error] Remote side has closed connection\n");
 454                         ret = -1;
 455                         goto error;
 456                 }
 457                 if (ret_len < 0) {
 458                         perror("[error] Error receiving stream");
 459                         ret = ret_len;
 460                         goto error;
 461                 }
 462                 assert(ret_len == sizeof(stream));
 463                 stream.path_name[LTTNG_VIEWER_PATH_MAX - 1] = '\0';
 464                 stream.channel_name[LTTNG_VIEWER_NAME_MAX - 1] = '\0';
 465
 466                 printf_verbose("    stream %" PRIu64 " : %s/%s\n",
 467                                 be64toh(stream.id), stream.path_name,
 468                                 stream.channel_name);
 469                 ctx->session->streams[i].id = be64toh(stream.id);
 470                 ctx->session->streams[i].session = ctx->session;
 471
 472                 ctx->session->streams[i].first_read = 1;
 473                 ctx->session->streams[i].mmap_size = 0;
 474
 475                 if (be32toh(stream.metadata_flag)) {
 476                         char *path;
 477
 478                         path = strdup(LTTNG_METADATA_PATH_TEMPLATE);
 479                         if (!path) {
 480                                 perror("strdup");
 481                                 ret = -1;
 482                                 goto error;
 483                         }
 484                         if (!mkdtemp(path)) {
 485                                 perror("mkdtemp");
 486                                 free(path);
 487                                 ret = -1;
 488                                 goto error;
 489                         }
 490                         ctx->session->streams[i].metadata_flag = 1;
 491                         snprintf(ctx->session->streams[i].path,
 492                                         sizeof(ctx->session->streams[i].path),
 493                                         "%s/%s", path,
 494                                         stream.channel_name);
 495                         ret = open(ctx->session->streams[i].path,
 496                                         O_WRONLY | O_CREAT | O_TRUNC,
 497                                         S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
 498                         if (ret < 0) {
 499                                 perror("open");
 500                                 free(path);
 501                                 goto error;
 502                         }
 503                         ctx->session->streams[i].fd = ret;
 504                         free(path);
 505                 }
 506                 ret = lttng_live_ctf_trace_assign(&ctx->session->streams[i],
 507                                 be64toh(stream.ctf_trace_id));
 508                 if (ret < 0) {
 509                         goto error;
 510                 }
 511
 512         }
 513         ret = 0;
 514
 515 end:
 516 error:
 517         return ret;
 518 }
 519
 520 static
 521 int ask_new_streams(struct lttng_live_ctx *ctx)
 522 {
 523         int i, ret = 0;
 524         uint64_t id;
 525
 526 restart:
 527         for (i = 0; i < ctx->session_ids->len; i++) {
 528                 id = g_array_index(ctx->session_ids, uint64_t, i);
 529                 ret = lttng_live_get_new_streams(ctx, id);
 530                 printf_verbose("Asking for new streams returns %d\n",
 531                                 ret);
 532                 if (ret < 0) {
 533                         if (ret == -LTTNG_VIEWER_NEW_STREAMS_HUP) {
 534                                 printf_verbose("Session %" PRIu64 " closed\n",
 535                                                 id);
 536                                 /*
 537                                  * The streams have already been closed during
 538                                  * the reading, so we only need to get rid of
 539                                  * the trace in our internal table of sessions.
 540                                  */
 541                                 g_array_remove_index(ctx->session_ids, i);
 542                                 /*
 543                                  * We can't continue iterating on the g_array
 544                                  * after a remove, we have to start again.
 545                                  */
 546                                 goto restart;
 547                         } else {
 548                                 ret = -1;
 549                                 goto end;
 550                         }
 551                 }
 552         }
 553
 554 end:
 555         return ret;
 556 }
 557
 558 static
 559 int get_data_packet(struct lttng_live_ctx *ctx,
 560                 struct ctf_stream_pos *pos,
 561                 struct lttng_live_viewer_stream *stream, uint64_t offset,
 562                 uint64_t len)
 563 {
 564         struct lttng_viewer_cmd cmd;
 565         struct lttng_viewer_get_packet rq;
 566         struct lttng_viewer_trace_packet rp;
 567         ssize_t ret_len;
 568         int ret;
 569
 570         cmd.cmd = htobe32(LTTNG_VIEWER_GET_PACKET);
 571         cmd.data_size = sizeof(rq);
 572         cmd.cmd_version = 0;
 573
 574         memset(&rq, 0, sizeof(rq));
 575         rq.stream_id = htobe64(stream->id);
 576         /* Already in big endian. */
 577         rq.offset = offset;
 578         rq.len = htobe32(len);
 579
 580         do {
 581                 ret_len = send(ctx->control_sock, &cmd, sizeof(cmd), 0);
 582         } while (ret_len < 0 && errno == EINTR);
 583         if (ret_len < 0) {
 584                 perror("[error] Error sending cmd");
 585                 ret = ret_len;
 586                 goto error;
 587         }
 588         assert(ret_len == sizeof(cmd));
 589
 590         do {
 591                 ret_len = send(ctx->control_sock, &rq, sizeof(rq), 0);
 592         } while (ret_len < 0 && errno == EINTR);
 593         if (ret_len < 0) {
 594                 perror("[error] Error sending get_data_packet request");
 595                 ret = ret_len;
 596                 goto error;
 597         }
 598         assert(ret_len == sizeof(rq));
 599
 600         do {
 601                 ret_len = recv(ctx->control_sock, &rp, sizeof(rp), 0);
 602         } while (ret_len < 0 && errno == EINTR);
 603         if (ret_len == 0) {
 604                 fprintf(stderr, "[error] Remote side has closed connection\n");
 605                 ret = -1;
 606                 goto error;
 607         }
 608         if (ret_len < 0) {
 609                 perror("[error] Error receiving data response");
 610                 ret = ret_len;
 611                 goto error;
 612         }
 613         if (ret_len != sizeof(rp)) {
 614                 fprintf(stderr, "[error] get_data_packet: expected %" PRId64
 615                                 ", received %" PRId64 "\n", ret_len,
 616                                 sizeof(rp));
 617                 ret = -1;
 618                 goto error;
 619         }
 620
 621         rp.flags = be32toh(rp.flags);
 622
 623         switch (be32toh(rp.status)) {
 624         case LTTNG_VIEWER_GET_PACKET_OK:
 625                 len = be32toh(rp.len);
 626                 printf_verbose("get_data_packet: Ok, packet size : %" PRIu64
 627                                 "\n", len);
 628                 break;
 629         case LTTNG_VIEWER_GET_PACKET_RETRY:
 630                 printf_verbose("get_data_packet: retry\n");
 631                 ret = -1;
 632                 goto end;
 633         case LTTNG_VIEWER_GET_PACKET_ERR:
 634                 if (rp.flags & LTTNG_VIEWER_FLAG_NEW_METADATA) {
 635                         printf_verbose("get_data_packet: new metadata needed\n");
 636                         ret = 0;
 637                         goto end;
 638                 }
 639                 if (rp.flags & LTTNG_VIEWER_FLAG_NEW_STREAM) {
 640                         ret = ask_new_streams(ctx);
 641                         if (ret < 0)
 642                                 goto error;
 643                         g_hash_table_foreach(ctx->session->ctf_traces, add_traces,
 644                                         ctx->bt_ctx);
 645                 }
 646                 fprintf(stderr, "[error] get_data_packet: error\n");
 647                 ret = -1;
 648                 goto end;
 649         case LTTNG_VIEWER_GET_PACKET_EOF:
 650                 ret = -2;
 651                 goto error;
 652         default:
 653                 printf_verbose("get_data_packet: unknown\n");
 654                 assert(0);
 655                 ret = -1;
 656                 goto end;
 657         }
 658
 659         if (len <= 0) {
 660                 ret = -1;
 661                 goto end;
 662         }
 663
 664         if (len > stream->mmap_size) {
 665                 uint64_t new_size;
 666
 667                 new_size = max_t(uint64_t, len, stream->mmap_size << 1);
 668                 if (pos->base_mma) {
 669                         /* unmap old base */
 670                         ret = munmap_align(pos->base_mma);
 671                         if (ret) {
 672                                 perror("[error] Unable to unmap old base");
 673                                 ret = -1;
 674                                 goto error;
 675                         }
 676                         pos->base_mma = NULL;
 677                 }
 678                 pos->base_mma = mmap_align(new_size,
 679                                 PROT_READ | PROT_WRITE,
 680                                 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 681                 if (pos->base_mma == MAP_FAILED) {
 682                         perror("[error] mmap error");
 683                         pos->base_mma = NULL;
 684                         ret = -1;
 685                         goto error;
 686                 }
 687
 688                 stream->mmap_size = new_size;
 689                 printf_verbose("Expanding stream mmap size to %" PRIu64 " bytes\n",
 690                                 stream->mmap_size);
 691         }
 692
 693         do {
 694                 ret_len = recv(ctx->control_sock,
 695                         mmap_align_addr(pos->base_mma), len,
 696                         MSG_WAITALL);
 697         } while (ret_len < 0 && errno == EINTR);
 698         if (ret_len == 0) {
 699                 fprintf(stderr, "[error] Remote side has closed connection\n");
 700                 ret = -1;
 701                 goto error;
 702         }
 703         if (ret_len < 0) {
 704                 perror("[error] Error receiving trace packet");
 705                 ret = ret_len;
 706                 goto error;
 707         }
 708         assert(ret_len == len);
 709
 710 end:
 711 error:
 712         return ret;
 713 }
 714
 715 static
 716 int get_one_metadata_packet(struct lttng_live_ctx *ctx,
 717                 struct lttng_live_viewer_stream *metadata_stream)
 718 {
 719         uint64_t len = 0;
 720         int ret;
 721         struct lttng_viewer_cmd cmd;
 722         struct lttng_viewer_get_metadata rq;
 723         struct lttng_viewer_metadata_packet rp;
 724         char *data = NULL;
 725         ssize_t ret_len;
 726
 727         rq.stream_id = htobe64(metadata_stream->id);
 728         cmd.cmd = htobe32(LTTNG_VIEWER_GET_METADATA);
 729         cmd.data_size = sizeof(rq);
 730         cmd.cmd_version = 0;
 731
 732         do {
 733                 ret_len = send(ctx->control_sock, &cmd, sizeof(cmd), 0);
 734         } while (ret_len < 0 && errno == EINTR);
 735         if (ret_len < 0) {
 736                 perror("[error] Error sending cmd");
 737                 ret = ret_len;
 738                 goto error;
 739         }
 740         assert(ret_len == sizeof(cmd));
 741
 742         do {
 743                 ret_len = send(ctx->control_sock, &rq, sizeof(rq), 0);
 744         } while (ret_len < 0 && errno == EINTR);
 745         if (ret_len < 0) {
 746                 perror("[error] Error sending get_metadata request");
 747                 ret = ret_len;
 748                 goto error;
 749         }
 750         assert(ret_len == sizeof(rq));
 751
 752         do {
 753                 ret_len = recv(ctx->control_sock, &rp, sizeof(rp), 0);
 754         } while (ret_len < 0 && errno == EINTR);
 755         if (ret_len == 0) {
 756                 fprintf(stderr, "[error] Remote side has closed connection\n");
 757                 ret = -1;
 758                 goto error;
 759         }
 760         if (ret_len < 0) {
 761                 perror("[error] Error receiving metadata response");
 762                 ret = ret_len;
 763                 goto error;
 764         }
 765         assert(ret_len == sizeof(rp));
 766
 767         switch (be32toh(rp.status)) {
 768                 case LTTNG_VIEWER_METADATA_OK:
 769                         printf_verbose("get_metadata : OK\n");
 770                         break;
 771                 case LTTNG_VIEWER_NO_NEW_METADATA:
 772                         printf_verbose("get_metadata : NO NEW\n");
 773                         ret = 0;
 774                         goto end;
 775                 case LTTNG_VIEWER_METADATA_ERR:
 776                         printf_verbose("get_metadata : ERR\n");
 777                         ret = -1;
 778                         goto end;
 779                 default:
 780                         printf_verbose("get_metadata : UNKNOWN\n");
 781                         ret = -1;
 782                         goto end;
 783         }
 784
 785         len = be64toh(rp.len);
 786         printf_verbose("Writing %" PRIu64" bytes to metadata\n", len);
 787         if (len <= 0) {
 788                 ret = -1;
 789                 goto end;
 790         }
 791
 792         data = zmalloc(len);
 793         if (!data) {
 794                 perror("relay data zmalloc");
 795                 ret = -1;
 796                 goto error;
 797         }
 798         do {
 799                 ret_len = recv(ctx->control_sock, data, len, MSG_WAITALL);
 800         } while (ret_len < 0 && errno == EINTR);
 801         if (ret_len == 0) {
 802                 fprintf(stderr, "[error] Remote side has closed connection\n");
 803                 ret = -1;
 804                 free(data);
 805                 goto error;
 806         }
 807         if (ret_len < 0) {
 808                 perror("[error] Error receiving trace packet");
 809                 ret = ret_len;
 810                 free(data);
 811                 goto error;
 812         }
 813         assert(ret_len == len);
 814
 815         do {
 816                 ret_len = write(metadata_stream->fd, data, len);
 817         } while (ret_len < 0 && errno == EINTR);
 818         if (ret_len < 0) {
 819                 free(data);
 820                 ret = ret_len;
 821                 goto error;
 822         }
 823         assert(ret_len == len);
 824         ret = len;
 825
 826         free(data);
 827
 828 end:
 829 error:
 830         return ret;
 831 }
 832
 833 /*
 834  * Return 0 on success, a negative value on error.
 835  */
 836 static
 837 int get_new_metadata(struct lttng_live_ctx *ctx,
 838                 struct lttng_live_viewer_stream *viewer_stream)
 839 {
 840         int ret = 0;
 841         struct lttng_live_viewer_stream *metadata_stream;
 842
 843         metadata_stream = viewer_stream->ctf_trace->metadata_stream;
 844
 845         do {
 846                 /*
 847                  * get_one_metadata_packet returns the number of bytes
 848                  * received, 0 when we have received everything, a
 849                  * negative value on error.
 850                  */
 851                 ret = get_one_metadata_packet(ctx, metadata_stream);
 852         } while (ret > 0);
 853
 854         return ret;
 855 }
 856
 857 /*
 858  * Get one index for a stream.
 859  *
 860  * Returns 0 on success or a negative value on error.
 861  */
 862 static
 863 int get_next_index(struct lttng_live_ctx *ctx,
 864                 struct lttng_live_viewer_stream *viewer_stream,
 865                 struct packet_index *index)
 866 {
 867         struct lttng_viewer_cmd cmd;
 868         struct lttng_viewer_get_next_index rq;
 869         struct lttng_viewer_index rp;
 870         int ret;
 871         ssize_t ret_len;
 872
 873         cmd.cmd = htobe32(LTTNG_VIEWER_GET_NEXT_INDEX);
 874         cmd.data_size = sizeof(rq);
 875         cmd.cmd_version = 0;
 876
 877         memset(&rq, 0, sizeof(rq));
 878         rq.stream_id = htobe64(viewer_stream->id);
 879
 880 retry:
 881         do {
 882                 ret_len = send(ctx->control_sock, &cmd, sizeof(cmd), 0);
 883         } while (ret_len < 0 && errno == EINTR);
 884         if (ret_len < 0) {
 885                 perror("[error] Error sending cmd");
 886                 ret = ret_len;
 887                 goto error;
 888         }
 889         assert(ret_len == sizeof(cmd));
 890
 891         do {
 892                 ret_len = send(ctx->control_sock, &rq, sizeof(rq), 0);
 893         } while (ret_len < 0 && errno == EINTR);
 894         if (ret_len < 0) {
 895                 perror("[error] Error sending get_next_index request");
 896                 ret = ret_len;
 897                 goto error;
 898         }
 899         assert(ret_len == sizeof(rq));
 900
 901         do {
 902                 ret_len = recv(ctx->control_sock, &rp, sizeof(rp), 0);
 903         } while (ret_len < 0 && errno == EINTR);
 904         if (ret_len == 0) {
 905                 fprintf(stderr, "[error] Remote side has closed connection\n");
 906                 ret = -1;
 907                 goto error;
 908         }
 909         if (ret_len < 0) {
 910                 perror("[error] Error receiving index response");
 911                 ret = ret_len;
 912                 goto error;
 913         }
 914         assert(ret_len == sizeof(rp));
 915
 916         rp.flags = be32toh(rp.flags);
 917
 918         switch (be32toh(rp.status)) {
 919         case LTTNG_VIEWER_INDEX_INACTIVE:
 920                 printf_verbose("get_next_index: inactive\n");
 921                 memset(index, 0, sizeof(struct packet_index));
 922                 index->ts_cycles.timestamp_end = be64toh(rp.timestamp_end);
 923                 break;
 924         case LTTNG_VIEWER_INDEX_OK:
 925                 printf_verbose("get_next_index: Ok, need metadata update : %u\n",
 926                                 rp.flags & LTTNG_VIEWER_FLAG_NEW_METADATA);
 927                 index->offset = be64toh(rp.offset);
 928                 index->packet_size = be64toh(rp.packet_size);
 929                 index->content_size = be64toh(rp.content_size);
 930                 index->ts_cycles.timestamp_begin = be64toh(rp.timestamp_begin);
 931                 index->ts_cycles.timestamp_end = be64toh(rp.timestamp_end);
 932                 index->events_discarded = be64toh(rp.events_discarded);
 933
 934                 if (rp.flags & LTTNG_VIEWER_FLAG_NEW_METADATA) {
 935                         printf_verbose("get_next_index: new metadata needed\n");
 936                         ret = get_new_metadata(ctx, viewer_stream);
 937                         if (ret < 0) {
 938                                 goto error;
 939                         }
 940                 }
 941                 if (rp.flags & LTTNG_VIEWER_FLAG_NEW_STREAM) {
 942                         ret = ask_new_streams(ctx);
 943                         if (ret < 0)
 944                                 goto error;
 945                         g_hash_table_foreach(ctx->session->ctf_traces, add_traces,
 946                                         ctx->bt_ctx);
 947                 }
 948                 break;
 949         case LTTNG_VIEWER_INDEX_RETRY:
 950                 printf_verbose("get_next_index: retry\n");
 951                 sleep(1);
 952                 goto retry;
 953         case LTTNG_VIEWER_INDEX_HUP:
 954                 printf_verbose("get_next_index: stream hung up\n");
 955                 viewer_stream->id = -1ULL;
 956                 viewer_stream->fd = -1;
 957                 index->offset = EOF;
 958                 ctx->session->stream_count--;
 959                 break;
 960         case LTTNG_VIEWER_INDEX_ERR:
 961                 fprintf(stderr, "[error] get_next_index: error\n");
 962                 ret = -1;
 963                 goto error;
 964         default:
 965                 fprintf(stderr, "[error] get_next_index: unkwown value\n");
 966                 ret = -1;
 967                 goto error;
 968         }
 969
 970         ret = 0;
 971
 972 error:
 973         return ret;
 974 }
 975
 976 static
 977 void ctf_live_packet_seek(struct bt_stream_pos *stream_pos, size_t index,
 978                 int whence)
 979 {
 980         struct ctf_stream_pos *pos;
 981         struct ctf_file_stream *file_stream;
 982         struct packet_index *prev_index = NULL, *cur_index;
 983         struct lttng_live_viewer_stream *viewer_stream;
 984         struct lttng_live_session *session;
 985         int ret;
 986
 987 retry:
 988         pos = ctf_pos(stream_pos);
 989         file_stream = container_of(pos, struct ctf_file_stream, pos);
 990         viewer_stream = (struct lttng_live_viewer_stream *) pos->priv;
 991         session = viewer_stream->session;
 992
 993         switch (pos->packet_index->len) {
 994         case 0:
 995                 g_array_set_size(pos->packet_index, 1);
 996                 cur_index = &g_array_index(pos->packet_index,
 997                                 struct packet_index, 0);
 998                 break;
 999         case 1:
1000                 g_array_set_size(pos->packet_index, 2);
1001                 prev_index = &g_array_index(pos->packet_index,
1002                                 struct packet_index, 0);
1003                 cur_index = &g_array_index(pos->packet_index,
1004                                 struct packet_index, 1);
1005                 break;
1006         case 2:
1007                 g_array_index(pos->packet_index,
1008                         struct packet_index, 0) =
1009                                 g_array_index(pos->packet_index,
1010                                         struct packet_index, 1);
1011                 prev_index = &g_array_index(pos->packet_index,
1012                                 struct packet_index, 0);
1013                 cur_index = &g_array_index(pos->packet_index,
1014                                 struct packet_index, 1);
1015                 break;
1016         default:
1017                 abort();
1018                 break;
1019         }
1020         printf_verbose("get_next_index for stream %" PRIu64 "\n", viewer_stream->id);
1021         ret = get_next_index(session->ctx, viewer_stream, cur_index);
1022         if (ret < 0) {
1023                 pos->offset = EOF;
1024                 fprintf(stderr, "[error] get_next_index failed\n");
1025                 return;
1026         }
1027
1028         pos->packet_size = cur_index->packet_size;
1029         pos->content_size = cur_index->content_size;
1030         pos->mmap_base_offset = 0;
1031         if (cur_index->offset == EOF) {
1032                 pos->offset = EOF;
1033         } else {
1034                 pos->offset = 0;
1035         }
1036
1037         if (cur_index->content_size == 0) {
1038                 file_stream->parent.cycles_timestamp =
1039                                 cur_index->ts_cycles.timestamp_end;
1040                 file_stream->parent.real_timestamp = ctf_get_real_timestamp(
1041                                 &file_stream->parent,
1042                                 cur_index->ts_cycles.timestamp_end);
1043         } else {
1044                 /* Convert the timestamps and append to the real_index. */
1045                 cur_index->ts_real.timestamp_begin = ctf_get_real_timestamp(
1046                                 &file_stream->parent,
1047                                 cur_index->ts_cycles.timestamp_begin);
1048                 cur_index->ts_real.timestamp_end = ctf_get_real_timestamp(
1049                                 &file_stream->parent,
1050                                 cur_index->ts_cycles.timestamp_end);
1051
1052                 ctf_update_current_packet_index(&file_stream->parent,
1053                                 prev_index, cur_index);
1054
1055                 file_stream->parent.cycles_timestamp =
1056                                 cur_index->ts_cycles.timestamp_begin;
1057                 file_stream->parent.real_timestamp =
1058                                 cur_index->ts_real.timestamp_begin;
1059         }
1060
1061         if (pos->packet_size == 0 || pos->offset == EOF) {
1062                 goto end;
1063         }
1064
1065         printf_verbose("get_data_packet for stream %" PRIu64 "\n",
1066                         viewer_stream->id);
1067         ret = get_data_packet(session->ctx, pos, viewer_stream,
1068                         be64toh(cur_index->offset),
1069                         cur_index->packet_size / CHAR_BIT);
1070         if (ret == -2) {
1071                 goto retry;
1072         } else if (ret < 0) {
1073                 pos->offset = EOF;
1074                 fprintf(stderr, "[error] get_data_packet failed\n");
1075                 return;
1076         }
1077
1078         printf_verbose("Index received : packet_size : %" PRIu64
1079                         ", offset %" PRIu64 ", content_size %" PRIu64
1080                         ", timestamp_end : %" PRIu64 "\n",
1081                         cur_index->packet_size, cur_index->offset,
1082                         cur_index->content_size,
1083                         cur_index->ts_cycles.timestamp_end);
1084
1085         /* update trace_packet_header and stream_packet_context */
1086         if (pos->prot != PROT_WRITE && file_stream->parent.trace_packet_header) {
1087                 /* Read packet header */
1088                 ret = generic_rw(&pos->parent, &file_stream->parent.trace_packet_header->p);
1089                 if (ret) {
1090                         pos->offset = EOF;
1091                         fprintf(stderr, "[error] trace packet header read failed\n");
1092                         goto end;
1093                 }
1094         }
1095         if (pos->prot != PROT_WRITE && file_stream->parent.stream_packet_context) {
1096                 /* Read packet context */
1097                 ret = generic_rw(&pos->parent, &file_stream->parent.stream_packet_context->p);
1098                 if (ret) {
1099                         pos->offset = EOF;
1100                         fprintf(stderr, "[error] stream packet context read failed\n");
1101                         goto end;
1102                 }
1103         }
1104         pos->data_offset = pos->offset;
1105
1106 end:
1107         return;
1108 }
1109
1110 int lttng_live_create_viewer_session(struct lttng_live_ctx *ctx)
1111 {
1112         struct lttng_viewer_cmd cmd;
1113         struct lttng_viewer_create_session_response resp;
1114         int ret;
1115         ssize_t ret_len;
1116
1117         cmd.cmd = htobe32(LTTNG_VIEWER_CREATE_SESSION);
1118         cmd.data_size = 0;
1119         cmd.cmd_version = 0;
1120
1121         do {
1122                 ret_len = send(ctx->control_sock, &cmd, sizeof(cmd), 0);
1123         } while (ret_len < 0 && errno == EINTR);
1124         if (ret_len < 0) {
1125                 perror("[error] Error sending cmd");
1126                 ret = ret_len;
1127                 goto error;
1128         }
1129         assert(ret_len == sizeof(cmd));
1130
1131         do {
1132                 ret_len = recv(ctx->control_sock, &resp, sizeof(resp), 0);
1133         } while (ret_len < 0 && errno == EINTR);
1134         if (ret_len == 0) {
1135                 fprintf(stderr, "[error] Remote side has closed connection\n");
1136                 ret = -1;
1137                 goto error;
1138         }
1139         if (ret_len < 0) {
1140                 perror("[error] Error receiving create session reply");
1141                 ret = ret_len;
1142                 goto error;
1143         }
1144         assert(ret_len == sizeof(resp));
1145
1146         if (be32toh(resp.status) != LTTNG_VIEWER_CREATE_SESSION_OK) {
1147                 fprintf(stderr, "[error] Error creating viewer session\n");
1148                 ret = -1;
1149                 goto error;
1150         }
1151         ret = 0;
1152
1153 error:
1154         return ret;
1155 }
1156
1157 static
1158 int del_traces(gpointer key, gpointer value, gpointer user_data)
1159 {
1160         struct bt_context *bt_ctx = user_data;
1161         struct lttng_live_ctf_trace *trace = value;
1162         int ret;
1163
1164         ret = bt_context_remove_trace(bt_ctx, trace->trace_id);
1165         if (ret < 0)
1166                 fprintf(stderr, "[error] removing trace from context\n");
1167
1168         /* remove the key/value pair from the HT. */
1169         return 1;
1170 }
1171
1172 static
1173 void add_traces(gpointer key, gpointer value, gpointer user_data)
1174 {
1175         int i, ret;
1176         struct bt_context *bt_ctx = user_data;
1177         struct lttng_live_ctf_trace *trace = value;
1178         struct lttng_live_viewer_stream *stream;
1179         struct bt_mmap_stream *new_mmap_stream;
1180         struct bt_mmap_stream_list mmap_list;
1181         struct lttng_live_ctx *ctx = NULL;
1182
1183         /*
1184          * We don't know how many streams we will receive for a trace, so
1185          * once we are done receiving the traces, we add all the traces
1186          * received to the bt_context.
1187          * We can receive streams during the attach command or the
1188          * get_new_streams, so we have to make sure not to add multiple
1189          * times the same traces.
1190          * If a trace is already in the context, we just skip this function.
1191          */
1192         if (trace->in_use)
1193                 return;
1194
1195         BT_INIT_LIST_HEAD(&mmap_list.head);
1196
1197         for (i = 0; i < trace->streams->len; i++) {
1198                 stream = g_ptr_array_index(trace->streams, i);
1199                 ctx = stream->session->ctx;
1200
1201                 if (!stream->metadata_flag) {
1202                         new_mmap_stream = zmalloc(sizeof(struct bt_mmap_stream));
1203                         new_mmap_stream->priv = (void *) stream;
1204                         new_mmap_stream->fd = -1;
1205                         bt_list_add(&new_mmap_stream->list, &mmap_list.head);
1206                 } else {
1207                         /* Get all possible metadata before starting */
1208                         ret = get_new_metadata(ctx, stream);
1209                         if (ret)
1210                                 goto end_free;
1211                         trace->metadata_fp = fopen(stream->path, "r");
1212                 }
1213         }
1214
1215         if (!trace->metadata_fp) {
1216                 fprintf(stderr, "[error] No metadata stream opened\n");
1217                 goto end_free;
1218         }
1219
1220         ret = bt_context_add_trace(bt_ctx, NULL, "ctf",
1221                         ctf_live_packet_seek, &mmap_list, trace->metadata_fp);
1222         if (ret < 0) {
1223                 fprintf(stderr, "[error] Error adding trace\n");
1224                 goto end_free;
1225         }
1226
1227         if (bt_ctx->current_iterator) {
1228                 struct bt_trace_descriptor *td;
1229                 struct bt_trace_handle *handle;
1230
1231                 handle = (struct bt_trace_handle *) g_hash_table_lookup(
1232                                 bt_ctx->trace_handles,
1233                                 (gpointer) (unsigned long) ret);
1234                 td = handle->td;
1235                 bt_iter_add_trace(bt_ctx->current_iterator, td);
1236         }
1237
1238         trace->trace_id = ret;
1239         trace->in_use = 1;
1240
1241         goto end;
1242
1243 end_free:
1244         bt_context_put(bt_ctx);
1245 end:
1246         return;
1247 }
1248
1249 int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
1250 {
1251         struct lttng_viewer_cmd cmd;
1252         struct lttng_viewer_new_streams_request rq;
1253         struct lttng_viewer_new_streams_response rp;
1254         struct lttng_viewer_stream stream;
1255         int ret, i;
1256         ssize_t ret_len;
1257         uint32_t stream_count;
1258
1259         cmd.cmd = htobe32(LTTNG_VIEWER_GET_NEW_STREAMS);
1260         cmd.data_size = sizeof(rq);
1261         cmd.cmd_version = 0;
1262
1263         memset(&rq, 0, sizeof(rq));
1264         rq.session_id = htobe64(id);
1265
1266         do {
1267                 ret_len = send(ctx->control_sock, &cmd, sizeof(cmd), 0);
1268         } while (ret_len < 0 && errno == EINTR);
1269         if (ret_len < 0) {
1270                 perror("[error] Error sending cmd");
1271                 ret = ret_len;
1272                 goto error;
1273         }
1274         assert(ret_len == sizeof(cmd));
1275
1276         do {
1277                 ret_len = send(ctx->control_sock, &rq, sizeof(rq), 0);
1278         } while (ret_len < 0 && errno == EINTR);
1279         if (ret_len < 0) {
1280                 perror("[error] Error sending get_new_streams request");
1281                 ret = ret_len;
1282                 goto error;
1283         }
1284         assert(ret_len == sizeof(rq));
1285
1286         do {
1287                 ret_len = recv(ctx->control_sock, &rp, sizeof(rp), 0);
1288         } while (ret_len < 0 && errno == EINTR);
1289         if (ret_len == 0) {
1290                 fprintf(stderr, "[error] Remote side has closed connection\n");
1291                 ret = -1;
1292                 goto error;
1293         }
1294         if (ret_len < 0) {
1295                 perror("[error] Error receiving get_new_streams response");
1296                 ret = ret_len;
1297                 goto error;
1298         }
1299         assert(ret_len == sizeof(rp));
1300
1301         switch(be32toh(rp.status)) {
1302         case LTTNG_VIEWER_NEW_STREAMS_OK:
1303                 break;
1304         case LTTNG_VIEWER_NEW_STREAMS_NO_NEW:
1305                 ret = 0;
1306                 goto end;
1307         case LTTNG_VIEWER_NEW_STREAMS_HUP:
1308                 ret = -LTTNG_VIEWER_NEW_STREAMS_HUP;
1309                 goto end;
1310         case LTTNG_VIEWER_NEW_STREAMS_ERR:
1311                 fprintf(stderr, "[error] get_new_streams error\n");
1312                 ret = -1;
1313                 goto end;
1314         default:
1315                 fprintf(stderr, "[error] Unknown return code %u\n",
1316                                 be32toh(rp.status));
1317                 ret = -1;
1318                 goto end;
1319         }
1320
1321         stream_count = be32toh(rp.streams_count);
1322         ctx->session->stream_count += stream_count;
1323         /*
1324          * When the session is created but not started, we do an active wait
1325          * until it starts. It allows the viewer to start processing the trace
1326          * as soon as the session starts.
1327          */
1328         if (ctx->session->stream_count == 0) {
1329                 ret = 0;
1330                 goto end;
1331         }
1332         printf_verbose("Waiting for %" PRIu64 " streams:\n",
1333                 ctx->session->stream_count);
1334         ctx->session->streams = g_new0(struct lttng_live_viewer_stream,
1335                         ctx->session->stream_count);
1336         for (i = 0; i < stream_count; i++) {
1337                 do {
1338                         ret_len = recv(ctx->control_sock, &stream, sizeof(stream), 0);
1339                 } while (ret_len < 0 && errno == EINTR);
1340                 if (ret_len == 0) {
1341                         fprintf(stderr, "[error] Remote side has closed connection\n");
1342                         ret = -1;
1343                         goto error;
1344                 }
1345                 if (ret_len < 0) {
1346                         perror("[error] Error receiving stream");
1347                         ret = ret_len;
1348                         goto error;
1349                 }
1350                 assert(ret_len == sizeof(stream));
1351                 stream.path_name[LTTNG_VIEWER_PATH_MAX - 1] = '\0';
1352                 stream.channel_name[LTTNG_VIEWER_NAME_MAX - 1] = '\0';
1353
1354                 printf_verbose("    stream %" PRIu64 " : %s/%s\n",
1355                                 be64toh(stream.id), stream.path_name,
1356                                 stream.channel_name);
1357                 ctx->session->streams[i].id = be64toh(stream.id);
1358                 ctx->session->streams[i].session = ctx->session;
1359
1360                 ctx->session->streams[i].first_read = 1;
1361                 ctx->session->streams[i].mmap_size = 0;
1362
1363                 if (be32toh(stream.metadata_flag)) {
1364                         char *path;
1365
1366                         path = strdup(LTTNG_METADATA_PATH_TEMPLATE);
1367                         if (!path) {
1368                                 perror("strdup");
1369                                 ret = -1;
1370                                 goto error;
1371                         }
1372                         if (!mkdtemp(path)) {
1373                                 perror("mkdtemp");
1374                                 free(path);
1375                                 ret = -1;
1376                                 goto error;
1377                         }
1378                         ctx->session->streams[i].metadata_flag = 1;
1379                         snprintf(ctx->session->streams[i].path,
1380                                         sizeof(ctx->session->streams[i].path),
1381                                         "%s/%s", path,
1382                                         stream.channel_name);
1383                         ret = open(ctx->session->streams[i].path,
1384                                         O_WRONLY | O_CREAT | O_TRUNC,
1385                                         S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1386                         if (ret < 0) {
1387                                 perror("open");
1388                                 free(path);
1389                                 goto error;
1390                         }
1391                         ctx->session->streams[i].fd = ret;
1392                         free(path);
1393                 }
1394                 ret = lttng_live_ctf_trace_assign(&ctx->session->streams[i],
1395                                 be64toh(stream.ctf_trace_id));
1396                 if (ret < 0) {
1397                         goto error;
1398                 }
1399
1400         }
1401         ret = 0;
1402
1403 end:
1404 error:
1405         return ret;
1406 }
1407
1408 void lttng_live_read(struct lttng_live_ctx *ctx)
1409 {
1410         int ret, i;
1411         struct bt_ctf_iter *iter;
1412         const struct bt_ctf_event *event;
1413         struct bt_iter_pos begin_pos;
1414         struct bt_trace_descriptor *td_write;
1415         struct bt_format *fmt_write;
1416         struct ctf_text_stream_pos *sout;
1417         uint64_t id;
1418
1419         ctx->bt_ctx = bt_context_create();
1420         if (!ctx->bt_ctx) {
1421                 fprintf(stderr, "[error] bt_context_create allocation\n");
1422                 goto end;
1423         }
1424
1425         fmt_write = bt_lookup_format(g_quark_from_static_string("text"));
1426         if (!fmt_write) {
1427                 fprintf(stderr, "[error] ctf-text error\n");
1428                 goto end;
1429         }
1430
1431         td_write = fmt_write->open_trace(NULL, O_RDWR, NULL, NULL);
1432         if (!td_write) {
1433                 fprintf(stderr, "[error] Error opening output trace\n");
1434                 goto end_free;
1435         }
1436
1437         sout = container_of(td_write, struct ctf_text_stream_pos,
1438                         trace_descriptor);
1439         if (!sout->parent.event_cb)
1440                 goto end_free;
1441
1442         ret = lttng_live_create_viewer_session(ctx);
1443         if (ret < 0) {
1444                 goto end_free;
1445         }
1446
1447         for (i = 0; i < ctx->session_ids->len; i++) {
1448                 id = g_array_index(ctx->session_ids, uint64_t, i);
1449                 printf_verbose("Attaching to session %lu\n", id);
1450                 ret = lttng_live_attach_session(ctx, id);
1451                 printf_verbose("Attaching session returns %d\n", ret);
1452                 if (ret < 0) {
1453                         if (ret == -LTTNG_VIEWER_ATTACH_UNK) {
1454                                 fprintf(stderr, "[error] Unknown session ID\n");
1455                         }
1456                         goto end_free;
1457                 }
1458         }
1459
1460         /*
1461          * As long as the session is active, we try to get new streams.
1462          */
1463         for (;;) {
1464                 int flags;
1465
1466                 while (!ctx->session->stream_count) {
1467                         if (ctx->session_ids->len == 0)
1468                                 goto end_free;
1469                         ret = ask_new_streams(ctx);
1470                         if (ret < 0)
1471                                 goto end_free;
1472                 }
1473
1474                 g_hash_table_foreach(ctx->session->ctf_traces, add_traces,
1475                                 ctx->bt_ctx);
1476
1477                 begin_pos.type = BT_SEEK_BEGIN;
1478                 iter = bt_ctf_iter_create(ctx->bt_ctx, &begin_pos, NULL);
1479                 if (!iter) {
1480                         fprintf(stderr, "[error] Iterator creation error\n");
1481                         goto end;
1482                 }
1483                 for (;;) {
1484                         event = bt_ctf_iter_read_event_flags(iter, &flags);
1485                         if (!(flags & BT_ITER_FLAG_RETRY)) {
1486                                 if (!event) {
1487                                         /* End of trace */
1488                                         break;
1489                                 }
1490                                 ret = sout->parent.event_cb(&sout->parent,
1491                                                 event->parent->stream);
1492                                 if (ret) {
1493                                         fprintf(stderr, "[error] Writing "
1494                                                         "event failed.\n");
1495                                         goto end_free;
1496                                 }
1497                         }
1498                         ret = bt_iter_next(bt_ctf_get_iter(iter));
1499                         if (ret < 0) {
1500                                 goto end_free;
1501                         }
1502                 }
1503                 bt_ctf_iter_destroy(iter);
1504                 g_hash_table_foreach_remove(ctx->session->ctf_traces,
1505                                 del_traces, ctx->bt_ctx);
1506                 ctx->session->stream_count = 0;
1507         }
1508
1509 end_free:
1510         bt_context_put(ctx->bt_ctx);
1511 end:
1512         return;
1513 }