src/bin/lttng/commands/enable_channels.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License, version 2 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <popt.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <sys/stat.h>
  24 #include <sys/types.h>
  25 #include <unistd.h>
  26 #include <inttypes.h>
  27 #include <assert.h>
  28 #include <ctype.h>
  29
  30 #include "../command.h"
  31 #include "../utils.h"
  32
  33 #include <src/common/sessiond-comm/sessiond-comm.h>
  34 #include <src/common/utils.h>
  35
  36 static char *opt_channels;
  37 static int opt_kernel;
  38 static char *opt_session_name;
  39 static int opt_userspace;
  40 static struct lttng_channel chan;
  41 static char *opt_output;
  42 static int opt_buffer_uid;
  43 static int opt_buffer_pid;
  44 static int opt_buffer_global;
  45
  46 enum {
  47         OPT_HELP = 1,
  48         OPT_DISCARD,
  49         OPT_OVERWRITE,
  50         OPT_SUBBUF_SIZE,
  51         OPT_NUM_SUBBUF,
  52         OPT_SWITCH_TIMER,
  53         OPT_READ_TIMER,
  54         OPT_USERSPACE,
  55         OPT_LIST_OPTIONS,
  56         OPT_TRACEFILE_SIZE,
  57         OPT_TRACEFILE_COUNT,
  58 };
  59
  60 static struct lttng_handle *handle;
  61
  62 const char *output_mmap = "mmap";
  63 const char *output_splice = "splice";
  64
  65 static struct poptOption long_options[] = {
  66         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  67         {"help",           'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  68         {"session",        's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  69         {"kernel",         'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
  70         {"userspace",      'u', POPT_ARG_NONE, 0, OPT_USERSPACE, 0, 0},
  71         {"discard",        0,   POPT_ARG_NONE, 0, OPT_DISCARD, 0, 0},
  72         {"overwrite",      0,   POPT_ARG_NONE, 0, OPT_OVERWRITE, 0, 0},
  73         {"subbuf-size",    0,   POPT_ARG_STRING, 0, OPT_SUBBUF_SIZE, 0, 0},
  74         {"num-subbuf",     0,   POPT_ARG_INT, 0, OPT_NUM_SUBBUF, 0, 0},
  75         {"switch-timer",   0,   POPT_ARG_INT, 0, OPT_SWITCH_TIMER, 0, 0},
  76         {"read-timer",     0,   POPT_ARG_INT, 0, OPT_READ_TIMER, 0, 0},
  77         {"list-options",   0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  78         {"output",         0,   POPT_ARG_STRING, &opt_output, 0, 0, 0},
  79         {"buffers-uid",    0,   POPT_ARG_VAL, &opt_buffer_uid, 1, 0, 0},
  80         {"buffers-pid",    0,   POPT_ARG_VAL, &opt_buffer_pid, 1, 0, 0},
  81         {"buffers-global", 0,   POPT_ARG_VAL, &opt_buffer_global, 1, 0, 0},
  82         {"tracefile-size", 'C',   POPT_ARG_INT, 0, OPT_TRACEFILE_SIZE, 0, 0},
  83         {"tracefile-count", 'W',   POPT_ARG_INT, 0, OPT_TRACEFILE_COUNT, 0, 0},
  84         {0, 0, 0, 0, 0, 0, 0}
  85 };
  86
  87 /*
  88  * usage
  89  */
  90 static void usage(FILE *ofp)
  91 {
  92         fprintf(ofp, "usage: lttng enable-channel NAME[,NAME2,...] (-u | -k) [OPTIONS]\n");
  93         fprintf(ofp, "\n");
  94         fprintf(ofp, "Options:\n");
  95         fprintf(ofp, "  -h, --help               Show this help\n");
  96         fprintf(ofp, "      --list-options       Simple listing of options\n");
  97         fprintf(ofp, "  -s, --session NAME       Apply to session name\n");
  98         fprintf(ofp, "  -k, --kernel             Apply to the kernel tracer\n");
  99         fprintf(ofp, "  -u, --userspace          Apply to the user-space tracer\n");
 100         fprintf(ofp, "\n");
 101         fprintf(ofp, "Channel options:\n");
 102         fprintf(ofp, "      --discard            Discard event when buffers are full%s\n",
 103                 DEFAULT_CHANNEL_OVERWRITE ? "" : " (default)");
 104         fprintf(ofp, "      --overwrite          Flight recorder mode%s\n",
 105                 DEFAULT_CHANNEL_OVERWRITE ? " (default)" : "");
 106         fprintf(ofp, "      --subbuf-size SIZE   Subbuffer size in bytes {+k,+M,+G}\n");
 107         fprintf(ofp, "                               (default UST uid: %zu, UST pid: %zu, kernel: %zu, metadata: %zu)\n",
 108                 default_get_ust_uid_channel_subbuf_size(),
 109                 default_get_ust_pid_channel_subbuf_size(),
 110                 default_get_kernel_channel_subbuf_size(),
 111                 default_get_metadata_subbuf_size());
 112         fprintf(ofp, "                               Rounded up to the next power of 2.\n");
 113         fprintf(ofp, "      --num-subbuf NUM     Number of subbufers\n");
 114         fprintf(ofp, "                               (default UST uid: %u, UST pid: %u, kernel: %u, metadata: %u)\n",
 115                 DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM, DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM,
 116                 DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM, DEFAULT_METADATA_SUBBUF_NUM);
 117         fprintf(ofp, "                               Rounded up to the next power of 2.\n");
 118         fprintf(ofp, "      --switch-timer USEC  Switch timer interval in usec\n");
 119         fprintf(ofp, "                               (default UST uid: %u, UST pid: %u, kernel: %u, metadata: %u)\n",
 120                 DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER, DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER,
 121                 DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER, DEFAULT_METADATA_SWITCH_TIMER);
 122         fprintf(ofp, "      --read-timer USEC    Read timer interval in usec.\n");
 123         fprintf(ofp, "                               (default UST uid: %u, UST pid: %u, kernel: %u, metadata: %u)\n",
 124                 DEFAULT_UST_UID_CHANNEL_READ_TIMER, DEFAULT_UST_UID_CHANNEL_READ_TIMER,
 125                 DEFAULT_KERNEL_CHANNEL_READ_TIMER, DEFAULT_METADATA_READ_TIMER);
 126         fprintf(ofp, "      --output TYPE        Channel output type (Values: %s, %s)\n",
 127                         output_mmap, output_splice);
 128         fprintf(ofp, "                               (default UST uid: %s, UST pid: %s, kernel: %s, metadata: %s)\n",
 129                         DEFAULT_UST_UID_CHANNEL_OUTPUT == LTTNG_EVENT_MMAP ? output_mmap : output_splice,
 130                         DEFAULT_UST_PID_CHANNEL_OUTPUT == LTTNG_EVENT_MMAP ? output_mmap : output_splice,
 131                         DEFAULT_KERNEL_CHANNEL_OUTPUT == LTTNG_EVENT_MMAP ? output_mmap : output_splice,
 132                         DEFAULT_METADATA_OUTPUT == LTTNG_EVENT_MMAP ? output_mmap : output_splice);
 133         fprintf(ofp, "      --buffers-uid        Use per UID buffer (-u only)\n");
 134         fprintf(ofp, "      --buffers-pid        Use per PID buffer (-u only)\n");
 135         fprintf(ofp, "      --buffers-global     Use shared buffer for the whole system (-k only)\n");
 136         fprintf(ofp, "  -C, --tracefile-size SIZE\n");
 137         fprintf(ofp, "                           Maximum size of each tracefile within a stream (in bytes). 0 means unlimited.\n");
 138         fprintf(ofp, "                               (default: %u)\n", DEFAULT_CHANNEL_TRACEFILE_SIZE);
 139         fprintf(ofp, "                           Note: traces generated with this option may inaccurately report\n");
 140         fprintf(ofp, "                           discarded events as per CTF 1.8.\n");
 141         fprintf(ofp, "  -W, --tracefile-count COUNT\n");
 142         fprintf(ofp, "                           Used in conjunction with -C option, this will limit the number\n");
 143         fprintf(ofp, "                           of files created to the specified count. 0 means unlimited.\n");
 144         fprintf(ofp, "                               (default: %u)\n", DEFAULT_CHANNEL_TRACEFILE_COUNT);
 145         fprintf(ofp, "\n");
 146 }
 147
 148 /*
 149  * Set default attributes depending on those already defined from the command
 150  * line.
 151  */
 152 static void set_default_attr(struct lttng_domain *dom)
 153 {
 154         struct lttng_channel_attr default_attr;
 155
 156         /* Set attributes */
 157         lttng_channel_set_default_attr(dom, &default_attr);
 158
 159         if (chan.attr.overwrite == -1) {
 160                 chan.attr.overwrite = default_attr.overwrite;
 161         }
 162         if (chan.attr.subbuf_size == -1) {
 163                 chan.attr.subbuf_size = default_attr.subbuf_size;
 164         }
 165         if (chan.attr.num_subbuf == -1) {
 166                 chan.attr.num_subbuf = default_attr.num_subbuf;
 167         }
 168         if (chan.attr.switch_timer_interval == -1) {
 169                 chan.attr.switch_timer_interval = default_attr.switch_timer_interval;
 170         }
 171         if (chan.attr.read_timer_interval == -1) {
 172                 chan.attr.read_timer_interval = default_attr.read_timer_interval;
 173         }
 174         if ((int) chan.attr.output == -1) {
 175                 chan.attr.output = default_attr.output;
 176         }
 177         if (chan.attr.tracefile_count == -1) {
 178                 chan.attr.tracefile_count = default_attr.tracefile_count;
 179         }
 180         if (chan.attr.tracefile_size == -1) {
 181                 chan.attr.tracefile_size = default_attr.tracefile_size;
 182         }
 183 }
 184
 185 /*
 186  * Adding channel using the lttng API.
 187  */
 188 static int enable_channel(char *session_name)
 189 {
 190         int ret = CMD_SUCCESS, warn = 0;
 191         char *channel_name;
 192         struct lttng_domain dom;
 193
 194         memset(&dom, 0, sizeof(dom));
 195
 196         /* Create lttng domain */
 197         if (opt_kernel) {
 198                 dom.type = LTTNG_DOMAIN_KERNEL;
 199                 dom.buf_type = LTTNG_BUFFER_GLOBAL;
 200                 if (opt_buffer_uid || opt_buffer_pid) {
 201                         ERR("Buffer type not supported for domain -k");
 202                         ret = CMD_ERROR;
 203                         goto error;
 204                 }
 205         } else if (opt_userspace) {
 206                 dom.type = LTTNG_DOMAIN_UST;
 207                 if (opt_buffer_pid) {
 208                         dom.buf_type = LTTNG_BUFFER_PER_PID;
 209                 } else {
 210                         if (opt_buffer_global) {
 211                                 ERR("Buffer type not supported for domain -u");
 212                                 ret = CMD_ERROR;
 213                                 goto error;
 214                         }
 215                         dom.buf_type = LTTNG_BUFFER_PER_UID;
 216                 }
 217         } else {
 218                 print_missing_domain();
 219                 ret = CMD_ERROR;
 220                 goto error;
 221         }
 222
 223         set_default_attr(&dom);
 224
 225         if (chan.attr.tracefile_size == 0 && chan.attr.tracefile_count) {
 226                 ERR("Missing option --tracefile-size. "
 227                                 "A file count without a size won't do anything.");
 228                 ret = CMD_ERROR;
 229                 goto error;
 230         }
 231
 232         if ((chan.attr.tracefile_size > 0) &&
 233                         (chan.attr.tracefile_size < chan.attr.subbuf_size)) {
 234                 WARN("Tracefile size rounded up from (%" PRIu64 ") to subbuffer size (%" PRIu64 ")",
 235                                 chan.attr.tracefile_size, chan.attr.subbuf_size);
 236                 chan.attr.tracefile_size = chan.attr.subbuf_size;
 237         }
 238
 239         /* Setting channel output */
 240         if (opt_output) {
 241                 if (!strncmp(output_mmap, opt_output, strlen(output_mmap))) {
 242                         chan.attr.output = LTTNG_EVENT_MMAP;
 243                 } else if (!strncmp(output_splice, opt_output, strlen(output_splice))) {
 244                         chan.attr.output = LTTNG_EVENT_SPLICE;
 245                 } else {
 246                         ERR("Unknown output type %s. Possible values are: %s, %s\n",
 247                                         opt_output, output_mmap, output_splice);
 248                         usage(stderr);
 249                         ret = CMD_ERROR;
 250                         goto error;
 251                 }
 252         }
 253
 254         handle = lttng_create_handle(session_name, &dom);
 255         if (handle == NULL) {
 256                 ret = -1;
 257                 goto error;
 258         }
 259
 260         /* Strip channel list (format: chan1,chan2,...) */
 261         channel_name = strtok(opt_channels, ",");
 262         while (channel_name != NULL) {
 263                 /* Validate channel name's length */
 264                 if (strlen(channel_name) >= NAME_MAX) {
 265                         ERR("Channel name is too long (max. %zu characters)",
 266                                         sizeof(chan.name) - 1);
 267                         ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
 268                         goto error;
 269                 }
 270
 271                 /* Copy channel name */
 272                 strcpy(chan.name, channel_name);
 273
 274                 DBG("Enabling channel %s", channel_name);
 275
 276                 ret = lttng_enable_channel(handle, &chan);
 277                 if (ret < 0) {
 278                         switch (-ret) {
 279                         case LTTNG_ERR_KERN_CHAN_EXIST:
 280                         case LTTNG_ERR_UST_CHAN_EXIST:
 281                         case LTTNG_ERR_CHAN_EXIST:
 282                                 WARN("Channel %s: %s (session %s)", channel_name,
 283                                                 lttng_strerror(ret), session_name);
 284                                 goto error;
 285                         case LTTNG_ERR_INVALID_CHANNEL_NAME:
 286                                 ERR("Invalid channel name: \"%s\". "
 287                                     "Channel names may not start with '.', and "
 288                                     "may not contain '/'.", channel_name);
 289                                 goto error;
 290                         default:
 291                                 ERR("Channel %s: %s (session %s)", channel_name,
 292                                                 lttng_strerror(ret), session_name);
 293                                 break;
 294                         }
 295                         warn = 1;
 296                 } else {
 297                         MSG("%s channel %s enabled for session %s",
 298                                         get_domain_str(dom.type), channel_name, session_name);
 299                 }
 300
 301                 channel_name = strtok(NULL, ",");
 302         }
 303
 304         ret = CMD_SUCCESS;
 305
 306 error:
 307         if (warn) {
 308                 ret = CMD_WARNING;
 309         }
 310
 311         lttng_destroy_handle(handle);
 312
 313         return ret;
 314 }
 315
 316 /*
 317  * Default value for channel configuration.
 318  */
 319 static void init_channel_config(void)
 320 {
 321         /*
 322          * Put -1 everywhere so we can identify those set by the command line and
 323          * those needed to be set by the default values.
 324          */
 325         memset(&chan.attr, -1, sizeof(chan.attr));
 326 }
 327
 328 /*
 329  * Add channel to trace session
 330  */
 331 int cmd_enable_channels(int argc, const char **argv)
 332 {
 333         int opt, ret = CMD_SUCCESS;
 334         static poptContext pc;
 335         char *session_name = NULL;
 336         char *opt_arg = NULL;
 337
 338         init_channel_config();
 339
 340         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 341         poptReadDefaultConfig(pc, 0);
 342
 343         while ((opt = poptGetNextOpt(pc)) != -1) {
 344                 switch (opt) {
 345                 case OPT_HELP:
 346                         usage(stdout);
 347                         goto end;
 348                 case OPT_DISCARD:
 349                         chan.attr.overwrite = 0;
 350                         DBG("Channel set to discard");
 351                         break;
 352                 case OPT_OVERWRITE:
 353                         chan.attr.overwrite = 1;
 354                         DBG("Channel set to overwrite");
 355                         break;
 356                 case OPT_SUBBUF_SIZE:
 357                 {
 358                         uint64_t rounded_size;
 359                         int order;
 360
 361                         /* Parse the size */
 362                         opt_arg = poptGetOptArg(pc);
 363                         if (utils_parse_size_suffix(opt_arg, &chan.attr.subbuf_size) < 0 || !chan.attr.subbuf_size) {
 364                                 ERR("Wrong value in --subbuf-size parameter: %s", opt_arg);
 365                                 ret = CMD_ERROR;
 366                                 goto end;
 367                         }
 368
 369                         order = get_count_order_u64(chan.attr.subbuf_size);
 370                         assert(order >= 0);
 371                         rounded_size = 1ULL << order;
 372                         if (rounded_size < chan.attr.subbuf_size) {
 373                                 ERR("The subbuf size (%" PRIu64 ") is rounded and overflows!",
 374                                                 chan.attr.subbuf_size);
 375                                 ret = CMD_ERROR;
 376                                 goto end;
 377                         }
 378
 379                         if (rounded_size != chan.attr.subbuf_size) {
 380                                 WARN("The subbuf size (%" PRIu64 ") is rounded to the next power of 2 (%" PRIu64 ")",
 381                                                 chan.attr.subbuf_size, rounded_size);
 382                                 chan.attr.subbuf_size = rounded_size;
 383                         }
 384
 385                         /* Should now be power of 2 */
 386                         assert(!((chan.attr.subbuf_size - 1) & chan.attr.subbuf_size));
 387
 388                         DBG("Channel subbuf size set to %" PRIu64, chan.attr.subbuf_size);
 389                         break;
 390                 }
 391                 case OPT_NUM_SUBBUF:
 392                 {
 393                         uint64_t rounded_size;
 394                         int order;
 395
 396                         errno = 0;
 397                         opt_arg = poptGetOptArg(pc);
 398                         chan.attr.num_subbuf = strtoull(opt_arg, NULL, 0);
 399                         if (errno != 0 || !chan.attr.num_subbuf || !isdigit(opt_arg[0])) {
 400                                 ERR("Wrong value in --num-subbuf parameter: %s", opt_arg);
 401                                 ret = CMD_ERROR;
 402                                 goto end;
 403                         }
 404
 405                         order = get_count_order_u64(chan.attr.num_subbuf);
 406                         assert(order >= 0);
 407                         rounded_size = 1ULL << order;
 408                         if (rounded_size < chan.attr.num_subbuf) {
 409                                 ERR("The number of subbuffers (%" PRIu64 ") is rounded and overflows!",
 410                                                 chan.attr.num_subbuf);
 411                                 ret = CMD_ERROR;
 412                                 goto end;
 413                         }
 414
 415                         if (rounded_size != chan.attr.num_subbuf) {
 416                                 WARN("The number of subbuffers (%" PRIu64 ") is rounded to the next power of 2 (%" PRIu64 ")",
 417                                                 chan.attr.num_subbuf, rounded_size);
 418                                 chan.attr.num_subbuf = rounded_size;
 419                         }
 420
 421                         /* Should now be power of 2 */
 422                         assert(!((chan.attr.num_subbuf - 1) & chan.attr.num_subbuf));
 423
 424                         DBG("Channel subbuf num set to %" PRIu64, chan.attr.num_subbuf);
 425                         break;
 426                 }
 427                 case OPT_SWITCH_TIMER:
 428                 {
 429                         unsigned long v;
 430
 431                         errno = 0;
 432                         opt_arg = poptGetOptArg(pc);
 433                         v = strtoul(opt_arg, NULL, 0);
 434                         if (errno != 0 || !isdigit(opt_arg[0])) {
 435                                 ERR("Wrong value in --switch-timer parameter: %s", opt_arg);
 436                                 ret = CMD_ERROR;
 437                                 goto end;
 438                         }
 439                         if (v != (uint32_t) v) {
 440                                 ERR("32-bit overflow in --switch-timer parameter: %s", opt_arg);
 441                                 ret = CMD_ERROR;
 442                                 goto end;
 443                         }
 444                         chan.attr.switch_timer_interval = (uint32_t) v;
 445                         DBG("Channel switch timer interval set to %d", chan.attr.switch_timer_interval);
 446                         break;
 447                 }
 448                 case OPT_READ_TIMER:
 449                 {
 450                         unsigned long v;
 451
 452                         errno = 0;
 453                         opt_arg = poptGetOptArg(pc);
 454                         v = strtoul(opt_arg, NULL, 0);
 455                         if (errno != 0 || !isdigit(opt_arg[0])) {
 456                                 ERR("Wrong value in --read-timer parameter: %s", opt_arg);
 457                                 ret = CMD_ERROR;
 458                                 goto end;
 459                         }
 460                         if (v != (uint32_t) v) {
 461                                 ERR("32-bit overflow in --read-timer parameter: %s", opt_arg);
 462                                 ret = CMD_ERROR;
 463                                 goto end;
 464                         }
 465                         chan.attr.read_timer_interval = (uint32_t) v;
 466                         DBG("Channel read timer interval set to %d", chan.attr.read_timer_interval);
 467                         break;
 468                 }
 469                 case OPT_USERSPACE:
 470                         opt_userspace = 1;
 471                         break;
 472                 case OPT_TRACEFILE_SIZE:
 473                         opt_arg = poptGetOptArg(pc);
 474                         if (utils_parse_size_suffix(opt_arg, &chan.attr.tracefile_size) < 0) {
 475                                 ERR("Wrong value in --tracefile-size parameter: %s", opt_arg);
 476                                 ret = CMD_ERROR;
 477                                 goto end;
 478                         }
 479                         DBG("Maximum tracefile size set to %" PRIu64,
 480                                         chan.attr.tracefile_size);
 481                         break;
 482                 case OPT_TRACEFILE_COUNT:
 483                 {
 484                         unsigned long v;
 485
 486                         errno = 0;
 487                         opt_arg = poptGetOptArg(pc);
 488                         v = strtoul(opt_arg, NULL, 0);
 489                         if (errno != 0 || !isdigit(opt_arg[0])) {
 490                                 ERR("Wrong value in --tracefile-count parameter: %s", opt_arg);
 491                                 ret = CMD_ERROR;
 492                                 goto end;
 493                         }
 494                         if (v != (uint32_t) v) {
 495                                 ERR("32-bit overflow in --tracefile-count parameter: %s", opt_arg);
 496                                 ret = CMD_ERROR;
 497                                 goto end;
 498                         }
 499                         chan.attr.tracefile_count = (uint32_t) v;
 500                         DBG("Maximum tracefile count set to %" PRIu64,
 501                                         chan.attr.tracefile_count);
 502                         break;
 503                 }
 504                 case OPT_LIST_OPTIONS:
 505                         list_cmd_options(stdout, long_options);
 506                         goto end;
 507                 default:
 508                         usage(stderr);
 509                         ret = CMD_UNDEFINED;
 510                         goto end;
 511                 }
 512         }
 513
 514         opt_channels = (char*) poptGetArg(pc);
 515         if (opt_channels == NULL) {
 516                 ERR("Missing channel name.\n");
 517                 usage(stderr);
 518                 ret = CMD_ERROR;
 519                 goto end;
 520         }
 521
 522         if (!opt_session_name) {
 523                 session_name = get_session_name();
 524                 if (session_name == NULL) {
 525                         ret = CMD_ERROR;
 526                         goto end;
 527                 }
 528         } else {
 529                 session_name = opt_session_name;
 530         }
 531
 532         ret = enable_channel(session_name);
 533
 534 end:
 535         if (!opt_session_name && session_name) {
 536                 free(session_name);
 537         }
 538         poptFreeContext(pc);
 539         return ret;
 540 }