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 #include <poll.h>
  37
  38 #include <babeltrace/ctf/ctf-index.h>
  39
  40 #include <babeltrace/babeltrace.h>
  41 #include <babeltrace/ctf/events.h>
  42 #include <babeltrace/ctf/callbacks.h>
  43 #include <babeltrace/ctf/iterator.h>
  44
  45 /* for packet_index */
  46 #include <babeltrace/ctf/types.h>
  47
  48 #include <babeltrace/ctf/metadata.h>
  49 #include <babeltrace/ctf-text/types.h>
  50 #include <babeltrace/ctf/events-internal.h>
  51 #include <formats/ctf/events-private.h>
  52
  53 #include <babeltrace/compat/memstream.h>
  54
  55 #include "lttng-live.h"
  56 #include "lttng-viewer-abi.h"
  57
  58 #define ACTIVE_POLL_DELAY       100     /* ms */
  59
  60 /*
  61  * Memory allocation zeroed
  62  */
  63 #define zmalloc(x) calloc(1, x)
  64
  65 #ifndef max_t
  66 #define max_t(type, a, b)       \
  67         ((type) (a) > (type) (b) ? (type) (a) : (type) (b))
  68 #endif
  69
  70 static void ctf_live_packet_seek(struct bt_stream_pos *stream_pos,
  71                 size_t index, int whence);
  72 static void add_traces(gpointer key, gpointer value, gpointer user_data);
  73 static int del_traces(gpointer key, gpointer value, gpointer user_data);
  74 static int get_new_metadata(struct lttng_live_ctx *ctx,
  75                 struct lttng_live_viewer_stream *viewer_stream,
  76                 char **metadata_buf);
  77
  78 static
  79 ssize_t lttng_live_recv(int fd, void *buf, size_t len)
  80 {
  81         ssize_t ret;
  82         size_t copied = 0, to_copy = len;
  83
  84         do {
  85                 ret = recv(fd, buf + copied, to_copy, 0);
  86                 if (ret > 0) {
  87                         assert(ret <= to_copy);
  88                         copied += ret;
  89                         to_copy -= ret;
  90                 }
  91         } while ((ret > 0 && to_copy > 0)
  92                 || (ret < 0 && errno == EINTR));
  93         if (ret > 0)
  94                 ret = copied;
  95         /* ret = 0 means orderly shutdown, ret < 0 is error. */
  96         return ret;
  97 }
  98
  99 static
 100 ssize_t lttng_live_send(int fd, const void *buf, size_t len)
 101 {
 102         ssize_t ret;
 103
 104         do {
 105                 ret = send(fd, buf, len, MSG_NOSIGNAL);
 106         } while (ret < 0 && errno == EINTR);
 107         return ret;
 108 }
 109
 110 int lttng_live_connect_viewer(struct lttng_live_ctx *ctx)
 111 {
 112         struct hostent *host;
 113         struct sockaddr_in server_addr;
 114         int ret;
 115
 116         if (lttng_live_should_quit()) {
 117                 ret = -1;
 118                 goto end;
 119         }
 120
 121         host = gethostbyname(ctx->relay_hostname);
 122         if (!host) {
 123                 fprintf(stderr, "[error] Cannot lookup hostname %s\n",
 124                         ctx->relay_hostname);
 125                 goto error;
 126         }
 127
 128         if ((ctx->control_sock = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
 129                 perror("Socket");
 130                 goto error;
 131         }
 132
 133         server_addr.sin_family = AF_INET;
 134         server_addr.sin_port = htons(ctx->port);
 135         server_addr.sin_addr = *((struct in_addr *) host->h_addr);
 136         bzero(&(server_addr.sin_zero), 8);
 137
 138         if (connect(ctx->control_sock, (struct sockaddr *) &server_addr,
 139                                 sizeof(struct sockaddr)) == -1) {
 140                 perror("Connect");
 141                 goto error;
 142         }
 143
 144         ret = 0;
 145
 146 end:
 147         return ret;
 148
 149 error:
 150         fprintf(stderr, "[error] Connection failed\n");
 151         return -1;
 152 }
 153
 154 int lttng_live_establish_connection(struct lttng_live_ctx *ctx)
 155 {
 156         struct lttng_viewer_cmd cmd;
 157         struct lttng_viewer_connect connect;
 158         int ret;
 159         ssize_t ret_len;
 160
 161         if (lttng_live_should_quit()) {
 162                 ret = -1;
 163                 goto end;
 164         }
 165
 166         cmd.cmd = htobe32(LTTNG_VIEWER_CONNECT);
 167         cmd.data_size = sizeof(connect);
 168         cmd.cmd_version = 0;
 169
 170         connect.viewer_session_id = -1ULL;      /* will be set on recv */
 171         connect.major = htobe32(LTTNG_LIVE_MAJOR);
 172         connect.minor = htobe32(LTTNG_LIVE_MINOR);
 173         connect.type = htobe32(LTTNG_VIEWER_CLIENT_COMMAND);
 174
 175         ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
 176         if (ret_len < 0) {
 177                 perror("[error] Error sending cmd");
 178                 goto error;
 179         }
 180         assert(ret_len == sizeof(cmd));
 181
 182         ret_len = lttng_live_send(ctx->control_sock, &connect, sizeof(connect));
 183         if (ret_len < 0) {
 184                 perror("[error] Error sending version");
 185                 goto error;
 186         }
 187         assert(ret_len == sizeof(connect));
 188
 189         ret_len = lttng_live_recv(ctx->control_sock, &connect, sizeof(connect));
 190         if (ret_len == 0) {
 191                 fprintf(stderr, "[error] Remote side has closed connection\n");
 192                 goto error;
 193         }
 194         if (ret_len < 0) {
 195                 perror("[error] Error receiving version");
 196                 goto error;
 197         }
 198         assert(ret_len == sizeof(connect));
 199
 200         printf_verbose("Received viewer session ID : %" PRIu64 "\n",
 201                         be64toh(connect.viewer_session_id));
 202         printf_verbose("Relayd version : %u.%u\n", be32toh(connect.major),
 203                         be32toh(connect.minor));
 204
 205         if (LTTNG_LIVE_MAJOR != be32toh(connect.major)) {
 206                 fprintf(stderr, "[error] Incompatible lttng-relayd protocol\n");
 207                 goto error;
 208         }
 209         /* Use the smallest protocol version implemented. */
 210         if (LTTNG_LIVE_MINOR > be32toh(connect.minor)) {
 211                 ctx->minor =  be32toh(connect.minor);
 212         } else {
 213                 ctx->minor =  LTTNG_LIVE_MINOR;
 214         }
 215         ctx->major = LTTNG_LIVE_MAJOR;
 216         ret = 0;
 217 end:
 218         return ret;
 219
 220 error:
 221         fprintf(stderr, "[error] Unable to establish connection\n");
 222         return -1;
 223 }
 224
 225 static
 226 void free_session_list(GPtrArray *session_list)
 227 {
 228         int i;
 229         struct lttng_live_relay_session *relay_session;
 230
 231         for (i = 0; i < session_list->len; i++) {
 232                 relay_session = g_ptr_array_index(session_list, i);
 233                 free(relay_session->name);
 234                 free(relay_session->hostname);
 235         }
 236         g_ptr_array_free(session_list, TRUE);
 237 }
 238
 239 static
 240 void print_session_list(GPtrArray *session_list, const char *path)
 241 {
 242         int i;
 243         struct lttng_live_relay_session *relay_session;
 244
 245         for (i = 0; i < session_list->len; i++) {
 246                 relay_session = g_ptr_array_index(session_list, i);
 247                 fprintf(stdout, "%s/host/%s/%s (timer = %u, "
 248                                 "%u stream(s), %u client(s) connected)\n",
 249                                 path, relay_session->hostname,
 250                                 relay_session->name, relay_session->timer,
 251                                 relay_session->streams, relay_session->clients);
 252         }
 253 }
 254
 255 static
 256 void update_session_list(GPtrArray *session_list, char *hostname,
 257                 char *session_name, uint32_t streams, uint32_t clients,
 258                 uint32_t timer)
 259 {
 260         int i, found = 0;
 261         struct lttng_live_relay_session *relay_session;
 262
 263         for (i = 0; i < session_list->len; i++) {
 264                 relay_session = g_ptr_array_index(session_list, i);
 265                 if ((strncmp(relay_session->hostname, hostname, NAME_MAX) == 0) &&
 266                                 strncmp(relay_session->name,
 267                                         session_name, NAME_MAX) == 0) {
 268                         relay_session->streams += streams;
 269                         if (relay_session->clients < clients)
 270                                 relay_session->clients = clients;
 271                         found = 1;
 272                         break;
 273                 }
 274         }
 275         if (found)
 276                 return;
 277
 278         relay_session = g_new0(struct lttng_live_relay_session, 1);
 279         relay_session->hostname = strndup(hostname, NAME_MAX);
 280         relay_session->name = strndup(session_name, NAME_MAX);
 281         relay_session->clients = clients;
 282         relay_session->streams = streams;
 283         relay_session->timer = timer;
 284         g_ptr_array_add(session_list, relay_session);
 285 }
 286
 287 int lttng_live_list_sessions(struct lttng_live_ctx *ctx, const char *path)
 288 {
 289         struct lttng_viewer_cmd cmd;
 290         struct lttng_viewer_list_sessions list;
 291         struct lttng_viewer_session lsession;
 292         int i, ret, sessions_count, print_list = 0;
 293         ssize_t ret_len;
 294         uint64_t session_id;
 295         GPtrArray *session_list = NULL;
 296
 297         if (lttng_live_should_quit()) {
 298                 ret = -1;
 299                 goto end;
 300         }
 301
 302         if (strlen(ctx->session_name) == 0) {
 303                 print_list = 1;
 304                 session_list = g_ptr_array_new();
 305         }
 306
 307         cmd.cmd = htobe32(LTTNG_VIEWER_LIST_SESSIONS);
 308         cmd.data_size = 0;
 309         cmd.cmd_version = 0;
 310
 311         ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
 312         if (ret_len < 0) {
 313                 perror("[error] Error sending cmd");
 314                 goto error;
 315         }
 316         assert(ret_len == sizeof(cmd));
 317
 318         ret_len = lttng_live_recv(ctx->control_sock, &list, sizeof(list));
 319         if (ret_len == 0) {
 320                 fprintf(stderr, "[error] Remote side has closed connection\n");
 321                 goto error;
 322         }
 323         if (ret_len < 0) {
 324                 perror("[error] Error receiving session list");
 325                 goto error;
 326         }
 327         assert(ret_len == sizeof(list));
 328
 329         sessions_count = be32toh(list.sessions_count);
 330         for (i = 0; i < sessions_count; i++) {
 331                 ret_len = lttng_live_recv(ctx->control_sock, &lsession, sizeof(lsession));
 332                 if (ret_len == 0) {
 333                         fprintf(stderr, "[error] Remote side has closed connection\n");
 334                         goto error;
 335                 }
 336                 if (ret_len < 0) {
 337                         perror("[error] Error receiving session");
 338                         goto error;
 339                 }
 340                 assert(ret_len == sizeof(lsession));
 341                 lsession.hostname[LTTNG_VIEWER_HOST_NAME_MAX - 1] = '\0';
 342                 lsession.session_name[LTTNG_VIEWER_NAME_MAX - 1] = '\0';
 343                 session_id = be64toh(lsession.id);
 344
 345                 if (print_list) {
 346                         update_session_list(session_list,
 347                                         lsession.hostname,
 348                                         lsession.session_name,
 349                                         be32toh(lsession.streams),
 350                                         be32toh(lsession.clients),
 351                                         be32toh(lsession.live_timer));
 352                 } else {
 353                         if ((strncmp(lsession.session_name, ctx->session_name,
 354                                 NAME_MAX) == 0) && (strncmp(lsession.hostname,
 355                                         ctx->traced_hostname, NAME_MAX) == 0)) {
 356                                 printf_verbose("Reading from session %" PRIu64 "\n",
 357                                                 session_id);
 358                                 g_array_append_val(ctx->session_ids,
 359                                                 session_id);
 360                         }
 361                 }
 362         }
 363
 364         if (print_list) {
 365                 print_session_list(session_list, path);
 366                 free_session_list(session_list);
 367         }
 368         ret = 0;
 369 end:
 370         return ret;
 371
 372 error:
 373         fprintf(stderr, "[error] Unable to list sessions\n");
 374         return -1;
 375 }
 376
 377 int lttng_live_ctf_trace_assign(struct lttng_live_viewer_stream *stream,
 378                 uint64_t ctf_trace_id)
 379 {
 380         struct lttng_live_ctf_trace *trace;
 381         int ret = 0;
 382
 383         trace = g_hash_table_lookup(stream->session->ctf_traces,
 384                         (gpointer) ctf_trace_id);
 385         if (!trace) {
 386                 trace = g_new0(struct lttng_live_ctf_trace, 1);
 387                 trace->ctf_trace_id = ctf_trace_id;
 388                 trace->streams = g_ptr_array_new();
 389                 g_hash_table_insert(stream->session->ctf_traces,
 390                                 (gpointer) ctf_trace_id,
 391                                 trace);
 392         }
 393         if (stream->metadata_flag)
 394                 trace->metadata_stream = stream;
 395
 396         stream->ctf_trace = trace;
 397         g_ptr_array_add(trace->streams, stream);
 398
 399         return ret;
 400 }
 401
 402 static
 403 int open_metadata_fp_write(struct lttng_live_viewer_stream *stream,
 404                 char **metadata_buf, size_t *size)
 405 {
 406         int ret = 0;
 407
 408         stream->metadata_fp_write =
 409                 babeltrace_open_memstream(metadata_buf, size);
 410         if (!stream->metadata_fp_write) {
 411                 perror("Metadata open_memstream");
 412                 ret = -1;
 413         }
 414
 415         return ret;
 416 }
 417
 418 int lttng_live_attach_session(struct lttng_live_ctx *ctx, uint64_t id)
 419 {
 420         struct lttng_viewer_cmd cmd;
 421         struct lttng_viewer_attach_session_request rq;
 422         struct lttng_viewer_attach_session_response rp;
 423         struct lttng_viewer_stream stream;
 424         int ret, i;
 425         ssize_t ret_len;
 426
 427         if (lttng_live_should_quit()) {
 428                 ret = -1;
 429                 goto end;
 430         }
 431
 432         cmd.cmd = htobe32(LTTNG_VIEWER_ATTACH_SESSION);
 433         cmd.data_size = sizeof(rq);
 434         cmd.cmd_version = 0;
 435
 436         memset(&rq, 0, sizeof(rq));
 437         rq.session_id = htobe64(id);
 438         // TODO: add cmd line parameter to select seek beginning
 439         // rq.seek = htobe32(LTTNG_VIEWER_SEEK_BEGINNING);
 440         rq.seek = htobe32(LTTNG_VIEWER_SEEK_LAST);
 441
 442         ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
 443         if (ret_len < 0) {
 444                 perror("[error] Error sending cmd");
 445                 goto error;
 446         }
 447         assert(ret_len == sizeof(cmd));
 448
 449         ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
 450         if (ret_len < 0) {
 451                 perror("[error] Error sending attach request");
 452                 goto error;
 453         }
 454         assert(ret_len == sizeof(rq));
 455
 456         ret_len = lttng_live_recv(ctx->control_sock, &rp, sizeof(rp));
 457         if (ret_len == 0) {
 458                 fprintf(stderr, "[error] Remote side has closed connection\n");
 459                 goto error;
 460         }
 461         if (ret_len < 0) {
 462                 perror("[error] Error receiving attach response");
 463                 goto error;
 464         }
 465         assert(ret_len == sizeof(rp));
 466
 467         switch(be32toh(rp.status)) {
 468         case LTTNG_VIEWER_ATTACH_OK:
 469                 break;
 470         case LTTNG_VIEWER_ATTACH_UNK:
 471                 ret = -LTTNG_VIEWER_ATTACH_UNK;
 472                 goto end;
 473         case LTTNG_VIEWER_ATTACH_ALREADY:
 474                 fprintf(stderr, "[error] There is already a viewer attached to this session\n");
 475                 goto error;
 476         case LTTNG_VIEWER_ATTACH_NOT_LIVE:
 477                 fprintf(stderr, "[error] Not a live session\n");
 478                 goto error;
 479         case LTTNG_VIEWER_ATTACH_SEEK_ERR:
 480                 fprintf(stderr, "[error] Wrong seek parameter\n");
 481                 goto error;
 482         default:
 483                 fprintf(stderr, "[error] Unknown attach return code %u\n",
 484                                 be32toh(rp.status));
 485                 goto error;
 486         }
 487         if (be32toh(rp.status) != LTTNG_VIEWER_ATTACH_OK) {
 488                 goto error;
 489         }
 490
 491         ctx->session->stream_count += be32toh(rp.streams_count);
 492         /*
 493          * When the session is created but not started, we do an active wait
 494          * until it starts. It allows the viewer to start processing the trace
 495          * as soon as the session starts.
 496          */
 497         if (ctx->session->stream_count == 0) {
 498                 ret = 0;
 499                 goto end;
 500         }
 501         printf_verbose("Waiting for %" PRIu64 " streams:\n",
 502                 ctx->session->stream_count);
 503         ctx->session->streams = g_new0(struct lttng_live_viewer_stream,
 504                         ctx->session->stream_count);
 505         for (i = 0; i < be32toh(rp.streams_count); i++) {
 506                 ret_len = lttng_live_recv(ctx->control_sock, &stream, sizeof(stream));
 507                 if (ret_len == 0) {
 508                         fprintf(stderr, "[error] Remote side has closed connection\n");
 509                         goto error;
 510                 }
 511                 if (ret_len < 0) {
 512                         perror("[error] Error receiving stream");
 513                         goto error;
 514                 }
 515                 assert(ret_len == sizeof(stream));
 516                 stream.path_name[LTTNG_VIEWER_PATH_MAX - 1] = '\0';
 517                 stream.channel_name[LTTNG_VIEWER_NAME_MAX - 1] = '\0';
 518
 519                 printf_verbose("    stream %" PRIu64 " : %s/%s\n",
 520                                 be64toh(stream.id), stream.path_name,
 521                                 stream.channel_name);
 522                 ctx->session->streams[i].id = be64toh(stream.id);
 523                 ctx->session->streams[i].session = ctx->session;
 524
 525                 ctx->session->streams[i].mmap_size = 0;
 526                 ctx->session->streams[i].ctf_stream_id = -1ULL;
 527
 528                 if (be32toh(stream.metadata_flag)) {
 529                         ctx->session->streams[i].metadata_flag = 1;
 530                 }
 531                 ret = lttng_live_ctf_trace_assign(&ctx->session->streams[i],
 532                                 be64toh(stream.ctf_trace_id));
 533                 if (ret < 0) {
 534                         goto error;
 535                 }
 536
 537         }
 538         ret = 0;
 539 end:
 540         return ret;
 541
 542 error:
 543         return -1;
 544 }
 545
 546 /*
 547  * Ask the relay for new streams.
 548  *
 549  * Returns the number of new streams received or a negative value on error.
 550  */
 551 static
 552 int ask_new_streams(struct lttng_live_ctx *ctx)
 553 {
 554         int i, ret = 0, nb_streams = 0;
 555         uint64_t id;
 556
 557 restart:
 558         for (i = 0; i < ctx->session_ids->len; i++) {
 559                 id = g_array_index(ctx->session_ids, uint64_t, i);
 560                 ret = lttng_live_get_new_streams(ctx, id);
 561                 printf_verbose("Asking for new streams returns %d\n", ret);
 562                 if (ret < 0) {
 563                         if (lttng_live_should_quit()) {
 564                                 goto end;
 565                         }
 566                         if (ret == -LTTNG_VIEWER_NEW_STREAMS_HUP) {
 567                                 printf_verbose("Session %" PRIu64 " closed\n",
 568                                                 id);
 569                                 /*
 570                                  * The streams have already been closed during
 571                                  * the reading, so we only need to get rid of
 572                                  * the trace in our internal table of sessions.
 573                                  */
 574                                 g_array_remove_index(ctx->session_ids, i);
 575                                 /*
 576                                  * We can't continue iterating on the g_array
 577                                  * after a remove, we have to start again.
 578                                  */
 579                                 goto restart;
 580                         } else {
 581                                 ret = -1;
 582                                 goto end;
 583                         }
 584                 } else {
 585                         nb_streams += ret;
 586                 }
 587         }
 588         ret = nb_streams;
 589
 590 end:
 591         return ret;
 592 }
 593
 594 static
 595 int append_metadata(struct lttng_live_ctx *ctx,
 596                 struct lttng_live_viewer_stream *viewer_stream)
 597 {
 598         int ret;
 599         struct lttng_live_viewer_stream *metadata;
 600         char *metadata_buf = NULL;
 601
 602         printf_verbose("get_next_index: new metadata needed\n");
 603         ret = get_new_metadata(ctx, viewer_stream, &metadata_buf);
 604         if (ret < 0) {
 605                 free(metadata_buf);
 606                 goto error;
 607         }
 608
 609         metadata = viewer_stream->ctf_trace->metadata_stream;
 610         metadata->ctf_trace->metadata_fp =
 611                 babeltrace_fmemopen(metadata_buf,
 612                                 metadata->metadata_len, "rb");
 613         if (!metadata->ctf_trace->metadata_fp) {
 614                 perror("Metadata fmemopen");
 615                 free(metadata_buf);
 616                 ret = -1;
 617                 goto error;
 618         }
 619         ret = ctf_append_trace_metadata(
 620                         viewer_stream->ctf_trace->handle->td,
 621                         metadata->ctf_trace->metadata_fp);
 622         /* We accept empty metadata packets */
 623         if (ret != 0 && ret != -ENOENT) {
 624                 fprintf(stderr, "[error] Appending metadata\n");
 625                 goto error;
 626         }
 627         ret = 0;
 628
 629 error:
 630         return ret;
 631 }
 632
 633 static
 634 int get_data_packet(struct lttng_live_ctx *ctx,
 635                 struct ctf_stream_pos *pos,
 636                 struct lttng_live_viewer_stream *stream, uint64_t offset,
 637                 uint64_t len)
 638 {
 639         struct lttng_viewer_cmd cmd;
 640         struct lttng_viewer_get_packet rq;
 641         struct lttng_viewer_trace_packet rp;
 642         ssize_t ret_len;
 643         int ret;
 644
 645 retry:
 646         if (lttng_live_should_quit()) {
 647                 ret = -1;
 648                 goto end;
 649         }
 650         cmd.cmd = htobe32(LTTNG_VIEWER_GET_PACKET);
 651         cmd.data_size = sizeof(rq);
 652         cmd.cmd_version = 0;
 653
 654         memset(&rq, 0, sizeof(rq));
 655         rq.stream_id = htobe64(stream->id);
 656         rq.offset = htobe64(offset);
 657         rq.len = htobe32(len);
 658
 659         ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
 660         if (ret_len < 0) {
 661                 perror("[error] Error sending cmd");
 662                 goto error;
 663         }
 664         assert(ret_len == sizeof(cmd));
 665
 666         ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
 667         if (ret_len < 0) {
 668                 perror("[error] Error sending get_data_packet request");
 669                 goto error;
 670         }
 671         assert(ret_len == sizeof(rq));
 672
 673         ret_len = lttng_live_recv(ctx->control_sock, &rp, sizeof(rp));
 674         if (ret_len == 0) {
 675                 fprintf(stderr, "[error] Remote side has closed connection\n");
 676                 goto error;
 677         }
 678         if (ret_len < 0) {
 679                 perror("[error] Error receiving data response");
 680                 goto error;
 681         }
 682         if (ret_len != sizeof(rp)) {
 683                 fprintf(stderr, "[error] get_data_packet: expected %" PRId64
 684                                 ", received %" PRId64 "\n", sizeof(rp),
 685                                 ret_len);
 686                 goto error;
 687         }
 688
 689         rp.flags = be32toh(rp.flags);
 690
 691         switch (be32toh(rp.status)) {
 692         case LTTNG_VIEWER_GET_PACKET_OK:
 693                 len = be32toh(rp.len);
 694                 printf_verbose("get_data_packet: Ok, packet size : %" PRIu64
 695                                 "\n", len);
 696                 break;
 697         case LTTNG_VIEWER_GET_PACKET_RETRY:
 698                 /* Unimplemented by relay daemon */
 699                 printf_verbose("get_data_packet: retry\n");
 700                 goto error;
 701         case LTTNG_VIEWER_GET_PACKET_ERR:
 702                 if (rp.flags & LTTNG_VIEWER_FLAG_NEW_METADATA) {
 703                         printf_verbose("get_data_packet: new metadata needed\n");
 704                         ret = append_metadata(ctx, stream);
 705                         if (ret)
 706                                 goto error;
 707                 }
 708                 if (rp.flags & LTTNG_VIEWER_FLAG_NEW_STREAM) {
 709                         printf_verbose("get_data_packet: new streams needed\n");
 710                         ret = ask_new_streams(ctx);
 711                         if (ret < 0)
 712                                 goto error;
 713                         else if (ret > 0)
 714                                 g_hash_table_foreach(ctx->session->ctf_traces,
 715                                                 add_traces, ctx->bt_ctx);
 716                 }
 717                 if (rp.flags & (LTTNG_VIEWER_FLAG_NEW_METADATA
 718                                 | LTTNG_VIEWER_FLAG_NEW_STREAM)) {
 719                         goto retry;
 720                 }
 721                 fprintf(stderr, "[error] get_data_packet: error\n");
 722                 goto error;
 723         case LTTNG_VIEWER_GET_PACKET_EOF:
 724                 ret = -2;
 725                 goto end;
 726         default:
 727                 printf_verbose("get_data_packet: unknown\n");
 728                 goto error;
 729         }
 730
 731         if (len == 0) {
 732                 goto error;
 733         }
 734
 735         if (len > stream->mmap_size) {
 736                 uint64_t new_size;
 737
 738                 new_size = max_t(uint64_t, len, stream->mmap_size << 1);
 739                 if (pos->base_mma) {
 740                         /* unmap old base */
 741                         ret = munmap_align(pos->base_mma);
 742                         if (ret) {
 743                                 perror("[error] Unable to unmap old base");
 744                                 goto error;
 745                         }
 746                         pos->base_mma = NULL;
 747                 }
 748                 pos->base_mma = mmap_align(new_size,
 749                                 PROT_READ | PROT_WRITE,
 750                                 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 751                 if (pos->base_mma == MAP_FAILED) {
 752                         perror("[error] mmap error");
 753                         pos->base_mma = NULL;
 754                         goto error;
 755                 }
 756
 757                 stream->mmap_size = new_size;
 758                 printf_verbose("Expanding stream mmap size to %" PRIu64 " bytes\n",
 759                                 stream->mmap_size);
 760         }
 761
 762         ret_len = lttng_live_recv(ctx->control_sock,
 763                         mmap_align_addr(pos->base_mma), len);
 764         if (ret_len == 0) {
 765                 fprintf(stderr, "[error] Remote side has closed connection\n");
 766                 goto error;
 767         }
 768         if (ret_len < 0) {
 769                 perror("[error] Error receiving trace packet");
 770                 goto error;
 771         }
 772         assert(ret_len == len);
 773         ret = 0;
 774 end:
 775         return ret;
 776
 777 error:
 778         return -1;
 779 }
 780
 781 static
 782 int get_one_metadata_packet(struct lttng_live_ctx *ctx,
 783                 struct lttng_live_viewer_stream *metadata_stream)
 784 {
 785         uint64_t len = 0;
 786         int ret;
 787         struct lttng_viewer_cmd cmd;
 788         struct lttng_viewer_get_metadata rq;
 789         struct lttng_viewer_metadata_packet rp;
 790         char *data = NULL;
 791         ssize_t ret_len;
 792
 793         if (lttng_live_should_quit()) {
 794                 ret = -1;
 795                 goto end;
 796         }
 797
 798         rq.stream_id = htobe64(metadata_stream->id);
 799         cmd.cmd = htobe32(LTTNG_VIEWER_GET_METADATA);
 800         cmd.data_size = sizeof(rq);
 801         cmd.cmd_version = 0;
 802
 803         ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
 804         if (ret_len < 0) {
 805                 perror("[error] Error sending cmd");
 806                 goto error;
 807         }
 808         assert(ret_len == sizeof(cmd));
 809
 810         ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
 811         if (ret_len < 0) {
 812                 perror("[error] Error sending get_metadata request");
 813                 goto error;
 814         }
 815         assert(ret_len == sizeof(rq));
 816
 817         ret_len = lttng_live_recv(ctx->control_sock, &rp, sizeof(rp));
 818         if (ret_len == 0) {
 819                 fprintf(stderr, "[error] Remote side has closed connection\n");
 820                 goto error;
 821         }
 822         if (ret_len < 0) {
 823                 perror("[error] Error receiving metadata response");
 824                 goto error;
 825         }
 826         assert(ret_len == sizeof(rp));
 827
 828         switch (be32toh(rp.status)) {
 829                 case LTTNG_VIEWER_METADATA_OK:
 830                         printf_verbose("get_metadata : OK\n");
 831                         break;
 832                 case LTTNG_VIEWER_NO_NEW_METADATA:
 833                         printf_verbose("get_metadata : NO NEW\n");
 834                         ret = 0;
 835                         goto end;
 836                 case LTTNG_VIEWER_METADATA_ERR:
 837                         printf_verbose("get_metadata : ERR\n");
 838                         goto error;
 839                 default:
 840                         printf_verbose("get_metadata : UNKNOWN\n");
 841                         goto error;
 842         }
 843
 844         len = be64toh(rp.len);
 845         printf_verbose("Writing %" PRIu64" bytes to metadata\n", len);
 846         if (len <= 0) {
 847                 goto error;
 848         }
 849
 850         data = zmalloc(len);
 851         if (!data) {
 852                 perror("relay data zmalloc");
 853                 goto error;
 854         }
 855         ret_len = lttng_live_recv(ctx->control_sock, data, len);
 856         if (ret_len == 0) {
 857                 fprintf(stderr, "[error] Remote side has closed connection\n");
 858                 goto error_free_data;
 859         }
 860         if (ret_len < 0) {
 861                 perror("[error] Error receiving trace packet");
 862                 goto error_free_data;
 863         }
 864         assert(ret_len == len);
 865
 866         do {
 867                 ret_len = fwrite(data, 1, len,
 868                                 metadata_stream->metadata_fp_write);
 869         } while (ret_len < 0 && errno == EINTR);
 870         if (ret_len < 0) {
 871                 fprintf(stderr, "[error] Writing in the metadata fp\n");
 872                 goto error_free_data;
 873         }
 874         assert(ret_len == len);
 875         metadata_stream->metadata_len += len;
 876         free(data);
 877         ret = len;
 878 end:
 879         return ret;
 880
 881 error_free_data:
 882         free(data);
 883 error:
 884         return -1;
 885 }
 886
 887 /*
 888  * Return 0 on success, a negative value on error.
 889  */
 890 static
 891 int get_new_metadata(struct lttng_live_ctx *ctx,
 892                 struct lttng_live_viewer_stream *viewer_stream,
 893                 char **metadata_buf)
 894 {
 895         int ret = 0;
 896         struct lttng_live_viewer_stream *metadata_stream;
 897         size_t size, len_read = 0;
 898
 899         metadata_stream = viewer_stream->ctf_trace->metadata_stream;
 900         if (!metadata_stream) {
 901                 fprintf(stderr, "[error] No metadata stream\n");
 902                 ret = -1;
 903                 goto error;
 904         }
 905         metadata_stream->metadata_len = 0;
 906         ret = open_metadata_fp_write(metadata_stream, metadata_buf, &size);
 907         if (ret < 0) {
 908                 goto error;
 909         }
 910
 911         do {
 912                 /*
 913                  * get_one_metadata_packet returns the number of bytes
 914                  * received, 0 when we have received everything, a
 915                  * negative value on error.
 916                  */
 917                 ret = get_one_metadata_packet(ctx, metadata_stream);
 918                 if (ret > 0) {
 919                         len_read += ret;
 920                 }
 921                 if (!len_read) {
 922                         (void) poll(NULL, 0, ACTIVE_POLL_DELAY);
 923                 }
 924         } while (ret > 0 || !len_read);
 925
 926         if (fclose(metadata_stream->metadata_fp_write))
 927                 perror("fclose");
 928         metadata_stream->metadata_fp_write = NULL;
 929
 930 error:
 931         return ret;
 932 }
 933
 934 /*
 935  * Assign the fields from a lttng_viewer_index to a packet_index.
 936  */
 937 static
 938 void lttng_index_to_packet_index(struct lttng_viewer_index *lindex,
 939                 struct packet_index *pindex)
 940 {
 941         assert(lindex);
 942         assert(pindex);
 943
 944         pindex->offset = be64toh(lindex->offset);
 945         pindex->packet_size = be64toh(lindex->packet_size);
 946         pindex->content_size = be64toh(lindex->content_size);
 947         pindex->ts_cycles.timestamp_begin = be64toh(lindex->timestamp_begin);
 948         pindex->ts_cycles.timestamp_end = be64toh(lindex->timestamp_end);
 949         pindex->events_discarded = be64toh(lindex->events_discarded);
 950 }
 951
 952 /*
 953  * Get one index for a stream.
 954  *
 955  * Returns 0 on success or a negative value on error.
 956  */
 957 static
 958 int get_next_index(struct lttng_live_ctx *ctx,
 959                 struct lttng_live_viewer_stream *viewer_stream,
 960                 struct packet_index *index, uint64_t *stream_id)
 961 {
 962         struct lttng_viewer_cmd cmd;
 963         struct lttng_viewer_get_next_index rq;
 964         int ret;
 965         ssize_t ret_len;
 966         struct lttng_viewer_index *rp = &viewer_stream->current_index;
 967
 968         cmd.cmd = htobe32(LTTNG_VIEWER_GET_NEXT_INDEX);
 969         cmd.data_size = sizeof(rq);
 970         cmd.cmd_version = 0;
 971
 972         memset(&rq, 0, sizeof(rq));
 973         rq.stream_id = htobe64(viewer_stream->id);
 974
 975 retry:
 976         if (lttng_live_should_quit()) {
 977                 ret = -1;
 978                 goto end;
 979         }
 980         ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
 981         if (ret_len < 0) {
 982                 perror("[error] Error sending cmd");
 983                 goto error;
 984         }
 985         assert(ret_len == sizeof(cmd));
 986
 987         ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
 988         if (ret_len < 0) {
 989                 perror("[error] Error sending get_next_index request");
 990                 goto error;
 991         }
 992         assert(ret_len == sizeof(rq));
 993
 994         ret_len = lttng_live_recv(ctx->control_sock, rp, sizeof(*rp));
 995         if (ret_len == 0) {
 996                 fprintf(stderr, "[error] Remote side has closed connection\n");
 997                 goto error;
 998         }
 999         if (ret_len < 0) {
1000                 perror("[error] Error receiving index response");
1001                 goto error;
1002         }
1003         assert(ret_len == sizeof(*rp));
1004
1005         rp->flags = be32toh(rp->flags);
1006
1007         switch (be32toh(rp->status)) {
1008         case LTTNG_VIEWER_INDEX_INACTIVE:
1009                 printf_verbose("get_next_index: inactive\n");
1010                 memset(index, 0, sizeof(struct packet_index));
1011                 index->ts_cycles.timestamp_end = be64toh(rp->timestamp_end);
1012                 *stream_id = be64toh(rp->stream_id);
1013                 break;
1014         case LTTNG_VIEWER_INDEX_OK:
1015                 printf_verbose("get_next_index: Ok, need metadata update : %u\n",
1016                                 rp->flags & LTTNG_VIEWER_FLAG_NEW_METADATA);
1017                 lttng_index_to_packet_index(rp, index);
1018                 *stream_id = be64toh(rp->stream_id);
1019                 viewer_stream->data_pending = 1;
1020
1021                 if (rp->flags & LTTNG_VIEWER_FLAG_NEW_METADATA) {
1022                         ret = append_metadata(ctx, viewer_stream);
1023                         if (ret)
1024                                 goto error;
1025                 }
1026                 if (rp->flags & LTTNG_VIEWER_FLAG_NEW_STREAM) {
1027                         printf_verbose("get_next_index: need new streams\n");
1028                         ret = ask_new_streams(ctx);
1029                         if (ret < 0)
1030                                 goto error;
1031                         else if (ret > 0)
1032                                 g_hash_table_foreach(ctx->session->ctf_traces,
1033                                                 add_traces, ctx->bt_ctx);
1034                 }
1035                 break;
1036         case LTTNG_VIEWER_INDEX_RETRY:
1037                 printf_verbose("get_next_index: retry\n");
1038                 (void) poll(NULL, 0, ACTIVE_POLL_DELAY);
1039                 goto retry;
1040         case LTTNG_VIEWER_INDEX_HUP:
1041                 printf_verbose("get_next_index: stream hung up\n");
1042                 viewer_stream->id = -1ULL;
1043                 index->offset = EOF;
1044                 ctx->session->stream_count--;
1045                 break;
1046         case LTTNG_VIEWER_INDEX_ERR:
1047                 fprintf(stderr, "[error] get_next_index: error\n");
1048                 goto error;
1049         default:
1050                 fprintf(stderr, "[error] get_next_index: unkwown value\n");
1051                 goto error;
1052         }
1053         ret = 0;
1054 end:
1055         return ret;
1056
1057 error:
1058         return -1;
1059 }
1060
1061 static
1062 void read_packet_header(struct ctf_stream_pos *pos,
1063                 struct ctf_file_stream *file_stream)
1064 {
1065         int ret;
1066
1067         /* update trace_packet_header and stream_packet_context */
1068         if (pos->prot != PROT_WRITE && file_stream->parent.trace_packet_header) {
1069                 /* Read packet header */
1070                 ret = generic_rw(&pos->parent,
1071                                 &file_stream->parent.trace_packet_header->p);
1072                 if (ret) {
1073                         pos->offset = EOF;
1074                         fprintf(stderr, "[error] trace packet "
1075                                         "header read failed\n");
1076                         goto end;
1077                 }
1078         }
1079         if (pos->prot != PROT_WRITE && file_stream->parent.stream_packet_context) {
1080                 /* Read packet context */
1081                 ret = generic_rw(&pos->parent,
1082                                 &file_stream->parent.stream_packet_context->p);
1083                 if (ret) {
1084                         pos->offset = EOF;
1085                         fprintf(stderr, "[error] stream packet "
1086                                         "context read failed\n");
1087                         goto end;
1088                 }
1089         }
1090         pos->data_offset = pos->offset;
1091
1092 end:
1093         return;
1094 }
1095
1096 /*
1097  * Handle the seek parameters.
1098  * Returns 0 if the packet_seek can continue, a positive value to
1099  * cleanly exit the packet_seek, a negative value on error.
1100  */
1101 static
1102 int handle_seek_position(size_t index, int whence,
1103                 struct lttng_live_viewer_stream *viewer_stream,
1104                 struct ctf_stream_pos *pos,
1105                 struct ctf_file_stream *file_stream)
1106 {
1107         int ret;
1108
1109         switch (whence) {
1110         case SEEK_CUR:
1111                 ret = 0;
1112                 goto end;
1113         case SEEK_SET:
1114                 /*
1115                  * We only allow to seek to 0.
1116                  */
1117                 if (index != 0) {
1118                         fprintf(stderr, "[error] Arbitrary seek in lttng-live "
1119                                         "trace not supported\n");
1120                         pos->offset = EOF;
1121                         ret = -1;
1122                         goto end;
1123                 }
1124
1125                 ret = 0;
1126                 goto end;
1127
1128         default:
1129                 fprintf(stderr, "[error] Invalid seek parameter\n");
1130                 assert(0);
1131         }
1132
1133 end:
1134         return ret;
1135 }
1136
1137 static
1138 void ctf_live_packet_seek(struct bt_stream_pos *stream_pos, size_t index,
1139                 int whence)
1140 {
1141         struct ctf_stream_pos *pos;
1142         struct ctf_file_stream *file_stream;
1143         struct packet_index *prev_index = NULL, *cur_index;
1144         struct lttng_live_viewer_stream *viewer_stream;
1145         struct lttng_live_session *session;
1146         uint64_t stream_id = -1ULL;
1147         int ret;
1148
1149         pos = ctf_pos(stream_pos);
1150         file_stream = container_of(pos, struct ctf_file_stream, pos);
1151         viewer_stream = (struct lttng_live_viewer_stream *) pos->priv;
1152         session = viewer_stream->session;
1153
1154         ret = handle_seek_position(index, whence, viewer_stream, pos,
1155                         file_stream);
1156         if (ret != 0) {
1157                 return;
1158         }
1159
1160 retry:
1161         switch (pos->packet_index->len) {
1162         case 0:
1163                 g_array_set_size(pos->packet_index, 1);
1164                 cur_index = &g_array_index(pos->packet_index,
1165                                 struct packet_index, 0);
1166                 break;
1167         case 1:
1168                 g_array_set_size(pos->packet_index, 2);
1169                 prev_index = &g_array_index(pos->packet_index,
1170                                 struct packet_index, 0);
1171                 cur_index = &g_array_index(pos->packet_index,
1172                                 struct packet_index, 1);
1173                 break;
1174         case 2:
1175                 g_array_index(pos->packet_index,
1176                         struct packet_index, 0) =
1177                                 g_array_index(pos->packet_index,
1178                                         struct packet_index, 1);
1179                 prev_index = &g_array_index(pos->packet_index,
1180                                 struct packet_index, 0);
1181                 cur_index = &g_array_index(pos->packet_index,
1182                                 struct packet_index, 1);
1183                 break;
1184         default:
1185                 abort();
1186                 break;
1187         }
1188
1189         if (viewer_stream->data_pending) {
1190                 lttng_index_to_packet_index(&viewer_stream->current_index, cur_index);
1191         } else {
1192                 printf_verbose("get_next_index for stream %" PRIu64 "\n", viewer_stream->id);
1193                 ret = get_next_index(session->ctx, viewer_stream, cur_index, &stream_id);
1194                 if (ret < 0) {
1195                         pos->offset = EOF;
1196                         if (!lttng_live_should_quit()) {
1197                                 fprintf(stderr, "[error] get_next_index failed\n");
1198                         }
1199                         return;
1200                 }
1201                 printf_verbose("Index received : packet_size : %" PRIu64
1202                                 ", offset %" PRIu64 ", content_size %" PRIu64
1203                                 ", timestamp_end : %" PRIu64 "\n",
1204                                 cur_index->packet_size, cur_index->offset,
1205                                 cur_index->content_size,
1206                                 cur_index->ts_cycles.timestamp_end);
1207
1208         }
1209
1210         /*
1211          * On the first time we receive an index, the stream_id needs to
1212          * be set for the stream in order to use it, we don't want any
1213          * data at this stage.
1214          */
1215         if (file_stream->parent.stream_id == -1ULL) {
1216                 /*
1217                  * Warning: with lttng-tools < 2.4.2, the beacon does not
1218                  * contain the real stream ID, it is memset to 0, so this
1219                  * might create a problem when a session has multiple
1220                  * channels. We can't detect it at this stage, lttng-tools
1221                  * has to be upgraded to fix this problem.
1222                  */
1223                 printf_verbose("Assigning stream_id %" PRIu64 "\n",
1224                                 stream_id);
1225                 file_stream->parent.stream_id = stream_id;
1226                 viewer_stream->ctf_stream_id = stream_id;
1227
1228                 return;
1229         }
1230
1231         pos->packet_size = cur_index->packet_size;
1232         pos->content_size = cur_index->content_size;
1233         pos->mmap_base_offset = 0;
1234         if (cur_index->offset == EOF) {
1235                 pos->offset = EOF;
1236         } else {
1237                 pos->offset = 0;
1238         }
1239
1240         if (cur_index->content_size == 0) {
1241                 if (file_stream->parent.stream_class) {
1242                         file_stream->parent.cycles_timestamp =
1243                                 cur_index->ts_cycles.timestamp_end;
1244                         file_stream->parent.real_timestamp = ctf_get_real_timestamp(
1245                                         &file_stream->parent,
1246                                         cur_index->ts_cycles.timestamp_end);
1247                 }
1248         } else {
1249                 if (file_stream->parent.stream_class) {
1250                         /* Convert the timestamps and append to the real_index. */
1251                         cur_index->ts_real.timestamp_begin = ctf_get_real_timestamp(
1252                                         &file_stream->parent,
1253                                         cur_index->ts_cycles.timestamp_begin);
1254                         cur_index->ts_real.timestamp_end = ctf_get_real_timestamp(
1255                                         &file_stream->parent,
1256                                         cur_index->ts_cycles.timestamp_end);
1257                 }
1258
1259                 ctf_update_current_packet_index(&file_stream->parent,
1260                                 prev_index, cur_index);
1261
1262                 file_stream->parent.cycles_timestamp =
1263                                 cur_index->ts_cycles.timestamp_begin;
1264                 file_stream->parent.real_timestamp =
1265                                 cur_index->ts_real.timestamp_begin;
1266         }
1267
1268         if (pos->packet_size == 0 || pos->offset == EOF) {
1269                 goto end;
1270         }
1271
1272         printf_verbose("get_data_packet for stream %" PRIu64 "\n",
1273                         viewer_stream->id);
1274         ret = get_data_packet(session->ctx, pos, viewer_stream,
1275                         cur_index->offset,
1276                         cur_index->packet_size / CHAR_BIT);
1277         if (ret == -2) {
1278                 goto retry;
1279         } else if (ret < 0) {
1280                 pos->offset = EOF;
1281                 if (!lttng_live_should_quit()) {
1282                         fprintf(stderr, "[error] get_data_packet failed\n");
1283                 }
1284                 return;
1285         }
1286         viewer_stream->data_pending = 0;
1287
1288         read_packet_header(pos, file_stream);
1289
1290 end:
1291         return;
1292 }
1293
1294 int lttng_live_create_viewer_session(struct lttng_live_ctx *ctx)
1295 {
1296         struct lttng_viewer_cmd cmd;
1297         struct lttng_viewer_create_session_response resp;
1298         int ret;
1299         ssize_t ret_len;
1300
1301         if (lttng_live_should_quit()) {
1302                 ret = -1;
1303                 goto end;
1304         }
1305
1306         cmd.cmd = htobe32(LTTNG_VIEWER_CREATE_SESSION);
1307         cmd.data_size = 0;
1308         cmd.cmd_version = 0;
1309
1310         ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
1311         if (ret_len < 0) {
1312                 perror("[error] Error sending cmd");
1313                 goto error;
1314         }
1315         assert(ret_len == sizeof(cmd));
1316
1317         ret_len = lttng_live_recv(ctx->control_sock, &resp, sizeof(resp));
1318         if (ret_len == 0) {
1319                 fprintf(stderr, "[error] Remote side has closed connection\n");
1320                 goto error;
1321         }
1322         if (ret_len < 0) {
1323                 perror("[error] Error receiving create session reply");
1324                 goto error;
1325         }
1326         assert(ret_len == sizeof(resp));
1327
1328         if (be32toh(resp.status) != LTTNG_VIEWER_CREATE_SESSION_OK) {
1329                 fprintf(stderr, "[error] Error creating viewer session\n");
1330                 goto error;
1331         }
1332         ret = 0;
1333 end:
1334         return ret;
1335
1336 error:
1337         return -1;
1338 }
1339
1340 static
1341 int del_traces(gpointer key, gpointer value, gpointer user_data)
1342 {
1343         struct bt_context *bt_ctx = user_data;
1344         struct lttng_live_ctf_trace *trace = value;
1345         int ret;
1346
1347         ret = bt_context_remove_trace(bt_ctx, trace->trace_id);
1348         if (ret < 0)
1349                 fprintf(stderr, "[error] removing trace from context\n");
1350
1351         /* remove the key/value pair from the HT. */
1352         return 1;
1353 }
1354
1355 static
1356 void add_traces(gpointer key, gpointer value, gpointer user_data)
1357 {
1358         int i, ret;
1359         struct bt_context *bt_ctx = user_data;
1360         struct lttng_live_ctf_trace *trace = value;
1361         struct lttng_live_viewer_stream *stream;
1362         struct bt_mmap_stream *new_mmap_stream;
1363         struct bt_mmap_stream_list mmap_list;
1364         struct lttng_live_ctx *ctx = NULL;
1365         struct bt_trace_descriptor *td;
1366         struct bt_trace_handle *handle;
1367
1368         /*
1369          * We don't know how many streams we will receive for a trace, so
1370          * once we are done receiving the traces, we add all the traces
1371          * received to the bt_context.
1372          * We can receive streams during the attach command or the
1373          * get_new_streams, so we have to make sure not to add multiple
1374          * times the same traces.
1375          * If a trace is already in the context, we just skip this function.
1376          */
1377         if (trace->in_use)
1378                 return;
1379
1380         BT_INIT_LIST_HEAD(&mmap_list.head);
1381
1382         for (i = 0; i < trace->streams->len; i++) {
1383                 stream = g_ptr_array_index(trace->streams, i);
1384                 ctx = stream->session->ctx;
1385
1386                 if (!stream->metadata_flag) {
1387                         new_mmap_stream = zmalloc(sizeof(struct bt_mmap_stream));
1388                         new_mmap_stream->priv = (void *) stream;
1389                         new_mmap_stream->fd = -1;
1390                         bt_list_add(&new_mmap_stream->list, &mmap_list.head);
1391                 } else {
1392                         char *metadata_buf = NULL;
1393
1394                         /* Get all possible metadata before starting */
1395                         ret = get_new_metadata(ctx, stream, &metadata_buf);
1396                         if (ret) {
1397                                 free(metadata_buf);
1398                                 goto end_free;
1399                         }
1400                         if (!stream->metadata_len) {
1401                                 fprintf(stderr, "[error] empty metadata\n");
1402                                 ret = -1;
1403                                 free(metadata_buf);
1404                                 goto end_free;
1405                         }
1406
1407                         trace->metadata_fp = babeltrace_fmemopen(metadata_buf,
1408                                         stream->metadata_len, "rb");
1409                         if (!trace->metadata_fp) {
1410                                 perror("Metadata fmemopen");
1411                                 ret = -1;
1412                                 free(metadata_buf);
1413                                 goto end_free;
1414                         }
1415                 }
1416         }
1417
1418         if (!trace->metadata_fp) {
1419                 fprintf(stderr, "[error] No metadata stream opened\n");
1420                 goto end_free;
1421         }
1422
1423         ret = bt_context_add_trace(bt_ctx, NULL, "ctf",
1424                         ctf_live_packet_seek, &mmap_list, trace->metadata_fp);
1425         if (ret < 0) {
1426                 fprintf(stderr, "[error] Error adding trace\n");
1427                 goto end_free;
1428         }
1429         trace->metadata_stream->metadata_len = 0;
1430
1431         handle = (struct bt_trace_handle *) g_hash_table_lookup(
1432                         bt_ctx->trace_handles,
1433                         (gpointer) (unsigned long) ret);
1434         td = handle->td;
1435         trace->handle = handle;
1436         if (bt_ctx->current_iterator) {
1437                 bt_iter_add_trace(bt_ctx->current_iterator, td);
1438         }
1439
1440         trace->trace_id = ret;
1441         trace->in_use = 1;
1442
1443         goto end;
1444
1445 end_free:
1446         bt_context_put(bt_ctx);
1447 end:
1448         return;
1449 }
1450
1451 /*
1452  * Request new streams for a session.
1453  * Returns the number of streams received or a negative value on error.
1454  */
1455 int lttng_live_get_new_streams(struct lttng_live_ctx *ctx, uint64_t id)
1456 {
1457         struct lttng_viewer_cmd cmd;
1458         struct lttng_viewer_new_streams_request rq;
1459         struct lttng_viewer_new_streams_response rp;
1460         struct lttng_viewer_stream stream;
1461         int ret, i, nb_streams = 0;
1462         ssize_t ret_len;
1463         uint32_t stream_count;
1464
1465         if (lttng_live_should_quit()) {
1466                 ret = -1;
1467                 goto end;
1468         }
1469
1470         cmd.cmd = htobe32(LTTNG_VIEWER_GET_NEW_STREAMS);
1471         cmd.data_size = sizeof(rq);
1472         cmd.cmd_version = 0;
1473
1474         memset(&rq, 0, sizeof(rq));
1475         rq.session_id = htobe64(id);
1476
1477         ret_len = lttng_live_send(ctx->control_sock, &cmd, sizeof(cmd));
1478         if (ret_len < 0) {
1479                 perror("[error] Error sending cmd");
1480                 goto error;
1481         }
1482         assert(ret_len == sizeof(cmd));
1483
1484         ret_len = lttng_live_send(ctx->control_sock, &rq, sizeof(rq));
1485         if (ret_len < 0) {
1486                 perror("[error] Error sending get_new_streams request");
1487                 goto error;
1488         }
1489         assert(ret_len == sizeof(rq));
1490
1491         ret_len = lttng_live_recv(ctx->control_sock, &rp, sizeof(rp));
1492         if (ret_len == 0) {
1493                 fprintf(stderr, "[error] Remote side has closed connection\n");
1494                 goto error;
1495         }
1496         if (ret_len < 0) {
1497                 perror("[error] Error receiving get_new_streams response");
1498                 goto error;
1499         }
1500         assert(ret_len == sizeof(rp));
1501
1502         switch(be32toh(rp.status)) {
1503         case LTTNG_VIEWER_NEW_STREAMS_OK:
1504                 break;
1505         case LTTNG_VIEWER_NEW_STREAMS_NO_NEW:
1506                 ret = 0;
1507                 goto end;
1508         case LTTNG_VIEWER_NEW_STREAMS_HUP:
1509                 ret = -LTTNG_VIEWER_NEW_STREAMS_HUP;
1510                 goto end;
1511         case LTTNG_VIEWER_NEW_STREAMS_ERR:
1512                 fprintf(stderr, "[error] get_new_streams error\n");
1513                 goto error;
1514         default:
1515                 fprintf(stderr, "[error] Unknown return code %u\n",
1516                                 be32toh(rp.status));
1517                 goto error;
1518         }
1519
1520         stream_count = be32toh(rp.streams_count);
1521         ctx->session->stream_count += stream_count;
1522         /*
1523          * When the session is created but not started, we do an active wait
1524          * until it starts. It allows the viewer to start processing the trace
1525          * as soon as the session starts.
1526          */
1527         if (ctx->session->stream_count == 0) {
1528                 ret = 0;
1529                 goto end;
1530         }
1531         printf_verbose("Waiting for %" PRIu64 " streams:\n",
1532                 ctx->session->stream_count);
1533         ctx->session->streams = g_new0(struct lttng_live_viewer_stream,
1534                         ctx->session->stream_count);
1535         for (i = 0; i < stream_count; i++) {
1536                 ret_len = lttng_live_recv(ctx->control_sock, &stream, sizeof(stream));
1537                 if (ret_len == 0) {
1538                         fprintf(stderr, "[error] Remote side has closed connection\n");
1539                         goto error;
1540                 }
1541                 if (ret_len < 0) {
1542                         perror("[error] Error receiving stream");
1543                         goto error;
1544                 }
1545                 assert(ret_len == sizeof(stream));
1546                 stream.path_name[LTTNG_VIEWER_PATH_MAX - 1] = '\0';
1547                 stream.channel_name[LTTNG_VIEWER_NAME_MAX - 1] = '\0';
1548
1549                 printf_verbose("    stream %" PRIu64 " : %s/%s\n",
1550                                 be64toh(stream.id), stream.path_name,
1551                                 stream.channel_name);
1552                 ctx->session->streams[i].id = be64toh(stream.id);
1553                 ctx->session->streams[i].session = ctx->session;
1554
1555                 ctx->session->streams[i].mmap_size = 0;
1556                 ctx->session->streams[i].ctf_stream_id = -1ULL;
1557
1558                 if (be32toh(stream.metadata_flag)) {
1559                         ctx->session->streams[i].metadata_flag = 1;
1560                 }
1561                 ret = lttng_live_ctf_trace_assign(&ctx->session->streams[i],
1562                                 be64toh(stream.ctf_trace_id));
1563                 if (ret < 0) {
1564                         goto error;
1565                 }
1566                 nb_streams++;
1567
1568         }
1569         ret = nb_streams;
1570 end:
1571         return ret;
1572
1573 error:
1574         return -1;
1575 }
1576
1577 int lttng_live_read(struct lttng_live_ctx *ctx)
1578 {
1579         int ret = -1;
1580         int i;
1581         struct bt_ctf_iter *iter;
1582         const struct bt_ctf_event *event;
1583         struct bt_iter_pos begin_pos;
1584         struct bt_trace_descriptor *td_write;
1585         struct bt_format *fmt_write;
1586         struct ctf_text_stream_pos *sout;
1587         uint64_t id;
1588
1589         ctx->bt_ctx = bt_context_create();
1590         if (!ctx->bt_ctx) {
1591                 fprintf(stderr, "[error] bt_context_create allocation\n");
1592                 goto end;
1593         }
1594
1595         fmt_write = bt_lookup_format(g_quark_from_static_string("text"));
1596         if (!fmt_write) {
1597                 fprintf(stderr, "[error] ctf-text error\n");
1598                 goto end;
1599         }
1600
1601         td_write = fmt_write->open_trace(NULL, O_RDWR, NULL, NULL);
1602         if (!td_write) {
1603                 fprintf(stderr, "[error] Error opening output trace\n");
1604                 goto end_free;
1605         }
1606
1607         sout = container_of(td_write, struct ctf_text_stream_pos,
1608                         trace_descriptor);
1609         if (!sout->parent.event_cb) {
1610                 goto end_free;
1611         }
1612
1613         ret = lttng_live_create_viewer_session(ctx);
1614         if (ret < 0) {
1615                 goto end_free;
1616         }
1617
1618         for (i = 0; i < ctx->session_ids->len; i++) {
1619                 id = g_array_index(ctx->session_ids, uint64_t, i);
1620                 printf_verbose("Attaching to session %lu\n", id);
1621                 ret = lttng_live_attach_session(ctx, id);
1622                 printf_verbose("Attaching session returns %d\n", ret);
1623                 if (ret < 0) {
1624                         if (ret == -LTTNG_VIEWER_ATTACH_UNK) {
1625                                 fprintf(stderr, "[error] Unknown session ID\n");
1626                         }
1627                         goto end_free;
1628                 }
1629         }
1630
1631         /*
1632          * As long as the session is active, we try to get new streams.
1633          */
1634         for (;;) {
1635                 int flags;
1636
1637                 if (lttng_live_should_quit()) {
1638                         ret = 0;
1639                         goto end_free;
1640                 }
1641
1642                 while (!ctx->session->stream_count) {
1643                         if (lttng_live_should_quit()
1644                                         || ctx->session_ids->len == 0) {
1645                                 ret = 0;
1646                                 goto end_free;
1647                         }
1648                         ret = ask_new_streams(ctx);
1649                         if (ret < 0) {
1650                                 goto end_free;
1651                         }
1652                         if (!ctx->session->stream_count) {
1653                                 (void) poll(NULL, 0, ACTIVE_POLL_DELAY);
1654                         }
1655                 }
1656
1657                 g_hash_table_foreach(ctx->session->ctf_traces, add_traces,
1658                                 ctx->bt_ctx);
1659
1660                 begin_pos.type = BT_SEEK_BEGIN;
1661                 iter = bt_ctf_iter_create(ctx->bt_ctx, &begin_pos, NULL);
1662                 if (!iter) {
1663                         if (lttng_live_should_quit()) {
1664                                 ret = 0;
1665                                 goto end;
1666                         }
1667                         fprintf(stderr, "[error] Iterator creation error\n");
1668                         goto end;
1669                 }
1670                 for (;;) {
1671                         if (lttng_live_should_quit()) {
1672                                 ret = 0;
1673                                 goto end_free;
1674                         }
1675                         event = bt_ctf_iter_read_event_flags(iter, &flags);
1676                         if (!(flags & BT_ITER_FLAG_RETRY)) {
1677                                 if (!event) {
1678                                         /* End of trace */
1679                                         break;
1680                                 }
1681                                 ret = sout->parent.event_cb(&sout->parent,
1682                                                 event->parent->stream);
1683                                 if (ret) {
1684                                         fprintf(stderr, "[error] Writing "
1685                                                         "event failed.\n");
1686                                         goto end_free;
1687                                 }
1688                         }
1689                         ret = bt_iter_next(bt_ctf_get_iter(iter));
1690                         if (ret < 0) {
1691                                 goto end_free;
1692                         }
1693                 }
1694                 bt_ctf_iter_destroy(iter);
1695                 g_hash_table_foreach_remove(ctx->session->ctf_traces,
1696                                 del_traces, ctx->bt_ctx);
1697                 ctx->session->stream_count = 0;
1698         }
1699
1700 end_free:
1701         bt_context_put(ctx->bt_ctx);
1702 end:
1703         if (lttng_live_should_quit()) {
1704                 ret = 0;
1705         }
1706         return ret;
1707 }