src/bin/lttng/commands/snapshot.c

   1 /*
   2  * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License, version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 51
  15  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <assert.h>
  20 #include <inttypes.h>
  21 #include <popt.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <sys/stat.h>
  26 #include <sys/types.h>
  27 #include <unistd.h>
  28
  29 #include <lttng/snapshot.h>
  30
  31 #include "../command.h"
  32
  33 static const char *opt_session_name;
  34 static const char *opt_output_name;
  35 static const char *opt_data_url;
  36 static const char *opt_ctrl_url;
  37 static const char *current_session_name;
  38 static uint64_t opt_max_size;
  39
  40 /* Stub for the cmd struct actions. */
  41 static int cmd_add_output(int argc, const char **argv);
  42 static int cmd_del_output(int argc, const char **argv);
  43 static int cmd_list_output(int argc, const char **argv);
  44 static int cmd_record(int argc, const char **argv);
  45
  46 static const char *indent4 = "    ";
  47
  48 enum {
  49         OPT_HELP = 1,
  50         OPT_LIST_OPTIONS,
  51         OPT_MAX_SIZE,
  52 };
  53
  54 static struct poptOption snapshot_opts[] = {
  55         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  56         {"help",      'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  57         {"session",      's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  58         {"ctrl-url",     'C', POPT_ARG_STRING, &opt_ctrl_url, 0, 0, 0},
  59         {"data-url",     'D', POPT_ARG_STRING, &opt_data_url, 0, 0, 0},
  60         {"name",         'n', POPT_ARG_STRING, &opt_output_name, 0, 0, 0},
  61         {"max-size",     'm', POPT_ARG_DOUBLE, 0, OPT_MAX_SIZE, 0, 0},
  62         {"list-options",   0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  63         {0, 0, 0, 0, 0, 0, 0}
  64 };
  65
  66 static struct cmd_struct actions[] = {
  67         { "add-output", cmd_add_output },
  68         { "del-output", cmd_del_output },
  69         { "list-output", cmd_list_output },
  70         { "record", cmd_record },
  71         { NULL, NULL }  /* Array closure */
  72 };
  73
  74 /*
  75  * usage
  76  */
  77 static void usage(FILE *ofp)
  78 {
  79         fprintf(ofp, "usage: lttng snapshot [ACTION]\n");
  80         fprintf(ofp, "\n");
  81         fprintf(ofp, "Actions:\n");
  82         fprintf(ofp, "   add-output [-m <SIZE>] [-s <NAME>] [-n <NAME>] <URL> | -C <URL> -D <URL>\n");
  83         fprintf(ofp, "      Setup and add an snapshot output for a session.\n");
  84         fprintf(ofp, "\n");
  85         fprintf(ofp, "   del-output ID [-s <NAME>]\n");
  86         fprintf(ofp, "      Delete an output for a session using the ID.\n");
  87         fprintf(ofp, "\n");
  88         fprintf(ofp, "   list-output [-s <NAME>]\n");
  89         fprintf(ofp, "      List the output of a session.\n");
  90         fprintf(ofp, "\n");
  91         fprintf(ofp, "   record [-m <SIZE>] [-s <NAME>] [-n <NAME>] [<URL> | -C <URL> -D <URL>]\n");
  92         fprintf(ofp, "      Snapshot a session's buffer(s) for all domains. If an URL is\n");
  93         fprintf(ofp, "      specified, it is used instead of a previously added output.\n");
  94         fprintf(ofp, "      The snapshot is saved in the session directory in snapshot/ with\n");
  95         fprintf(ofp, "      the top directory being NAME or the default: snapshot-ID/\n");
  96         fprintf(ofp, "\n");
  97         fprintf(ofp, "Options:\n");
  98         fprintf(ofp, "  -h, --help           Show this help\n");
  99         fprintf(ofp, "      --list-options   Simple listing of options\n");
 100         fprintf(ofp, "  -s, --session NAME   Apply to session name\n");
 101         fprintf(ofp, "  -n, --name NAME      Name of the output or snapshot\n");
 102         fprintf(ofp, "  -m, --max-size SIZE  Maximum bytes size of the snapshot\n");
 103         fprintf(ofp, "  -C, --ctrl-url URL   Set control path URL. (Must use -D also)\n");
 104         fprintf(ofp, "  -D, --data-url URL   Set data path URL. (Must use -C also)\n");
 105         fprintf(ofp, "\n");
 106 }
 107
 108 /*
 109  * Count and return the number of arguments in argv.
 110  */
 111 static int count_arguments(const char **argv)
 112 {
 113         int i = 0;
 114
 115         assert(argv);
 116
 117         while (argv[i] != NULL) {
 118                 i++;
 119         }
 120
 121         return i;
 122 }
 123
 124 /*
 125  * Create a snapshot output object from arguments using the given URL.
 126  *
 127  * Return a newly allocated object or NULL on error.
 128  */
 129 static struct lttng_snapshot_output *create_output_from_args(const char *url)
 130 {
 131         int ret = 0;
 132         struct lttng_snapshot_output *output = NULL;
 133
 134         output = lttng_snapshot_output_create();
 135         if (!output) {
 136                 goto error_create;
 137         }
 138
 139         if (url) {
 140                 ret = lttng_snapshot_output_set_ctrl_url(url, output);
 141                 if (ret < 0) {
 142                         goto error;
 143                 }
 144         } else if (opt_ctrl_url) {
 145                 ret = lttng_snapshot_output_set_ctrl_url(opt_ctrl_url, output);
 146                 if (ret < 0) {
 147                         goto error;
 148                 }
 149         }
 150
 151         if (opt_data_url) {
 152                 ret = lttng_snapshot_output_set_data_url(opt_data_url, output);
 153                 if (ret < 0) {
 154                         goto error;
 155                 }
 156         }
 157
 158         if (opt_max_size) {
 159                 ret = lttng_snapshot_output_set_size(opt_max_size, output);
 160                 if (ret < 0) {
 161                         goto error;
 162                 }
 163         }
 164
 165         if (opt_output_name) {
 166                 ret = lttng_snapshot_output_set_name(opt_output_name, output);
 167                 if (ret < 0) {
 168                         goto error;
 169                 }
 170         }
 171
 172         return output;
 173
 174 error:
 175         lttng_snapshot_output_destroy(output);
 176 error_create:
 177         return NULL;
 178 }
 179
 180 static int list_output(void)
 181 {
 182         int ret, output_seen = 0;
 183         struct lttng_snapshot_output *s_iter;
 184         struct lttng_snapshot_output_list *list;
 185
 186         ret = lttng_snapshot_list_output(current_session_name, &list);
 187         if (ret < 0) {
 188                 goto error;
 189         }
 190
 191         MSG("Snapshot output list for session %s", current_session_name);
 192
 193         while ((s_iter = lttng_snapshot_output_list_get_next(list)) != NULL) {
 194                 MSG("%s[%" PRIu32 "] %s: %s", indent4,
 195                                 lttng_snapshot_output_get_id(s_iter),
 196                                 lttng_snapshot_output_get_name(s_iter),
 197                                 lttng_snapshot_output_get_ctrl_url(s_iter));
 198                 output_seen = 1;
 199         }
 200
 201         lttng_snapshot_output_list_destroy(list);
 202
 203         if (!output_seen) {
 204                 MSG("%sNone", indent4);
 205         }
 206
 207 error:
 208         return ret;
 209 }
 210
 211 /*
 212  * Delete output by ID.
 213  */
 214 static int del_output(uint32_t id)
 215 {
 216         int ret;
 217         struct lttng_snapshot_output *output = NULL;
 218
 219         output = lttng_snapshot_output_create();
 220         if (!output) {
 221                 ret = CMD_FATAL;
 222                 goto error;
 223         }
 224
 225         ret = lttng_snapshot_output_set_id(id, output);
 226         if (ret < 0) {
 227                 ret = CMD_FATAL;
 228                 goto error;
 229         }
 230
 231         ret = lttng_snapshot_del_output(current_session_name, output);
 232         if (ret < 0) {
 233                 goto error;
 234         }
 235
 236         MSG("Snapshot output id %" PRIu32 " successfully deleted for session %s",
 237                         id, current_session_name);
 238
 239 error:
 240         lttng_snapshot_output_destroy(output);
 241         return ret;
 242 }
 243
 244 /*
 245  * Add output from the user URL.
 246  */
 247 static int add_output(const char *url)
 248 {
 249         int ret;
 250         struct lttng_snapshot_output *output = NULL;
 251
 252         if (!url && (!opt_data_url || !opt_ctrl_url)) {
 253                 ret = CMD_ERROR;
 254                 goto error;
 255         }
 256
 257         output = create_output_from_args(url);
 258         if (!output) {
 259                 ret = CMD_FATAL;
 260                 goto error;
 261         }
 262
 263         /* This call, if successful, populates the id of the output object. */
 264         ret = lttng_snapshot_add_output(current_session_name, output);
 265         if (ret < 0) {
 266                 goto error;
 267         }
 268
 269         MSG("Snapshot output successfully added for session %s",
 270                         current_session_name);
 271         MSG("  [%" PRIu32 "] %s: %s (max-size: %" PRId64 ")",
 272                         lttng_snapshot_output_get_id(output),
 273                         lttng_snapshot_output_get_name(output),
 274                         lttng_snapshot_output_get_ctrl_url(output),
 275                         lttng_snapshot_output_get_maxsize(output));
 276 error:
 277         lttng_snapshot_output_destroy(output);
 278         return ret;
 279 }
 280
 281 static int cmd_add_output(int argc, const char **argv)
 282 {
 283         int ret = CMD_SUCCESS;
 284
 285         if (argc < 2 && (!opt_data_url || !opt_ctrl_url)) {
 286                 usage(stderr);
 287                 ret = CMD_ERROR;
 288                 goto end;
 289         }
 290
 291         ret = add_output(argv[1]);
 292
 293 end:
 294         return ret;
 295 }
 296
 297 static int cmd_del_output(int argc, const char **argv)
 298 {
 299         int ret = CMD_SUCCESS;
 300
 301         if (argc < 2) {
 302                 usage(stderr);
 303                 ret = CMD_ERROR;
 304                 goto end;
 305         }
 306
 307         ret = del_output(atoi(argv[1]));
 308
 309 end:
 310         return ret;
 311 }
 312
 313 static int cmd_list_output(int argc, const char **argv)
 314 {
 315         return list_output();
 316 }
 317
 318 /*
 319  * Do a snapshot record with the URL if one is given.
 320  */
 321 static int record(const char *url)
 322 {
 323         int ret;
 324         struct lttng_snapshot_output *output = NULL;
 325
 326         output = create_output_from_args(url);
 327         if (!output) {
 328                 ret = CMD_FATAL;
 329                 goto error;
 330         }
 331
 332         ret = lttng_snapshot_record(current_session_name, output, 0);
 333         if (ret < 0) {
 334                 goto error;
 335         }
 336
 337         MSG("Snapshot recorded successfully for session %s", current_session_name);
 338
 339         if (url) {
 340                 MSG("Snapshot written at: %s", url);
 341         } else if (opt_ctrl_url) {
 342                 MSG("Snapshot written to ctrl: %s, data: %s", opt_ctrl_url,
 343                                 opt_data_url);
 344         }
 345
 346 error:
 347         lttng_snapshot_output_destroy(output);
 348         return ret;
 349 }
 350
 351 static int cmd_record(int argc, const char **argv)
 352 {
 353         int ret;
 354
 355         if (argc == 2) {
 356                 /* With a given URL */
 357                 ret = record(argv[1]);
 358         } else {
 359                 ret = record(NULL);
 360         }
 361
 362         return ret;
 363 }
 364
 365 static int handle_command(const char **argv)
 366 {
 367         int ret, i = 0, argc;
 368         struct cmd_struct *cmd;
 369
 370         if (argv == NULL || (!opt_ctrl_url && opt_data_url) ||
 371                         (opt_ctrl_url && !opt_data_url)) {
 372                 usage(stderr);
 373                 ret = CMD_ERROR;
 374                 goto end;
 375         }
 376
 377         argc = count_arguments(argv);
 378
 379         cmd = &actions[i];
 380         while (cmd->func != NULL) {
 381                 /* Find command */
 382                 if (strcmp(argv[0], cmd->name) == 0) {
 383                         ret = cmd->func(argc, argv);
 384                         goto end;
 385                 }
 386                 i++;
 387                 cmd = &actions[i];
 388         }
 389
 390         /* Command not found */
 391         ret = CMD_UNDEFINED;
 392
 393 end:
 394         return ret;
 395 }
 396
 397 /*
 398  * The 'snapshot <cmd> <options>' first level command
 399  */
 400 int cmd_snapshot(int argc, const char **argv)
 401 {
 402         int opt, ret = CMD_SUCCESS;
 403         char *session_name = NULL;
 404         static poptContext pc;
 405
 406         pc = poptGetContext(NULL, argc, argv, snapshot_opts, 0);
 407         poptReadDefaultConfig(pc, 0);
 408
 409         while ((opt = poptGetNextOpt(pc)) != -1) {
 410                 switch (opt) {
 411                 case OPT_HELP:
 412                         usage(stdout);
 413                         goto end;
 414                 case OPT_LIST_OPTIONS:
 415                         list_cmd_options(stdout, snapshot_opts);
 416                         goto end;
 417                 case OPT_MAX_SIZE:
 418                 {
 419                         long long int val;
 420                         char *endptr;
 421                         const char *opt = poptGetOptArg(pc);
 422
 423                         /* Documented by the man page of strtoll(3). */
 424                         errno = 0;
 425                         val = strtoll(opt, &endptr, 10);
 426                         if ((errno == ERANGE && (val == LLONG_MAX || val == LONG_MIN))
 427                                         || (errno != 0 && val == 0)) {
 428                                 ERR("Unable to handle max-size value %s", opt);
 429                                 ret = CMD_ERROR;
 430                                 goto end;
 431                         }
 432
 433                         if (endptr == opt) {
 434                                 ERR("No digits were found in %s", opt);
 435                                 ret = CMD_ERROR;
 436                                 goto end;
 437                         }
 438                         opt_max_size = val;
 439
 440                         break;
 441                 }
 442                 default:
 443                         usage(stderr);
 444                         ret = CMD_UNDEFINED;
 445                         goto end;
 446                 }
 447         }
 448
 449         if (!opt_session_name) {
 450                 session_name = get_session_name();
 451                 if (session_name == NULL) {
 452                         ret = CMD_ERROR;
 453                         goto end;
 454                 }
 455                 current_session_name = session_name;
 456         } else {
 457                 current_session_name = opt_session_name;
 458         }
 459
 460         ret = handle_command(poptGetArgs(pc));
 461         if (ret < 0) {
 462                 if (ret == -LTTNG_ERR_EPERM) {
 463                         ERR("The session needs to be set in no output mode (--no-output)");
 464                 }
 465                 ERR("%s", lttng_strerror(ret));
 466                 goto end;
 467         }
 468
 469 end:
 470         if (!opt_session_name) {
 471                 free(session_name);
 472         }
 473         poptFreeContext(pc);
 474         return ret;
 475 }