src/bin/lttng/commands/metadata.c

   1 /*
   2  * Copyright (C) 2015 - Julien Desfossez <jdesfossez@efficios.com>
   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 _LGPL_SOURCE
  19 #include <assert.h>
  20 #include <ctype.h>
  21 #include <popt.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26
  27 #include <common/mi-lttng.h>
  28
  29 #include "../command.h"
  30
  31 static char *opt_session_name;
  32 static char *session_name = NULL;
  33
  34 static int metadata_regenerate(int argc, const char **argv);
  35
  36 enum {
  37         OPT_HELP = 1,
  38         OPT_LIST_OPTIONS,
  39         OPT_LIST_COMMANDS,
  40 };
  41
  42 static struct mi_writer *writer;
  43
  44 static struct poptOption long_options[] = {
  45         /* { longName, shortName, argInfo, argPtr, value, descrip, argDesc, } */
  46         { "help",               'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0, },
  47         { "session",            's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  48         { "list-options",       0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, 0, 0, },
  49         { "list-commands",      0, POPT_ARG_NONE, NULL, OPT_LIST_COMMANDS},
  50         { 0, 0, 0, 0, 0, 0, 0, },
  51 };
  52
  53 static struct cmd_struct actions[] = {
  54         { "regenerate", metadata_regenerate },
  55         { NULL, NULL }  /* Array closure */
  56 };
  57
  58 /*
  59  * Count and return the number of arguments in argv.
  60  */
  61 static int count_arguments(const char **argv)
  62 {
  63         int i = 0;
  64
  65         assert(argv);
  66
  67         while (argv[i] != NULL) {
  68                 i++;
  69         }
  70
  71         return i;
  72 }
  73
  74 static int metadata_regenerate(int argc, const char **argv)
  75 {
  76         int ret;
  77
  78         if (argc > 1) {
  79                 ret = -LTTNG_ERR_INVALID;
  80                 goto end;
  81         }
  82         ret = lttng_metadata_regenerate(session_name);
  83         if (ret == 0) {
  84                 MSG("Metadata successfully regenerated for session %s", session_name);
  85         }
  86
  87 end:
  88         return ret;
  89 }
  90
  91 static int handle_command(const char **argv)
  92 {
  93         struct cmd_struct *cmd;
  94         int ret = CMD_SUCCESS, i = 0, argc, command_ret = CMD_SUCCESS;
  95
  96         if (argv == NULL) {
  97                 ERR("argv is null");
  98                 command_ret = CMD_ERROR;
  99                 goto end;
 100         }
 101
 102         argc = count_arguments(argv);
 103
 104         cmd = &actions[i];
 105         while (cmd->func != NULL) {
 106                 /* Find command */
 107                 if (strcmp(argv[0], cmd->name) == 0) {
 108                         if (lttng_opt_mi) {
 109                                 /* Action element */
 110                                 ret = mi_lttng_writer_open_element(writer,
 111                                                 mi_lttng_element_command_metadata_action);
 112                                 if (ret) {
 113                                         ret = CMD_ERROR;
 114                                         goto end;
 115                                 }
 116
 117                                 /* Name of the action */
 118                                 ret = mi_lttng_writer_write_element_string(writer,
 119                                                 config_element_name, argv[0]);
 120                                 if (ret) {
 121                                         ret = CMD_ERROR;
 122                                         goto end;
 123                                 }
 124                         }
 125                         command_ret = cmd->func(argc, argv);
 126                         if (lttng_opt_mi) {
 127                                 /* Close output and action element */
 128                                 ret = mi_lttng_writer_close_element(writer);
 129                                 if (ret) {
 130                                         ret = CMD_ERROR;
 131                                         goto end;
 132                                 }
 133                         }
 134                         goto end;
 135                 }
 136
 137                 cmd = &actions[i++];
 138         }
 139
 140         ret = CMD_UNDEFINED;
 141
 142 end:
 143         /* Overwrite ret if an error occurred in cmd->func() */
 144         ret = command_ret ? command_ret : ret;
 145         return ret;
 146 }
 147
 148 /*
 149  * Metadata command handling.
 150  */
 151 int cmd_metadata(int argc, const char **argv)
 152 {
 153         int opt, ret = CMD_SUCCESS, command_ret = CMD_SUCCESS, success = 1;
 154         static poptContext pc;
 155
 156         if (argc < 1) {
 157                 SHOW_HELP();
 158                 ret = CMD_ERROR;
 159                 goto end;
 160         }
 161
 162         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 163         poptReadDefaultConfig(pc, 0);
 164
 165         if (lttng_opt_mi) {
 166                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 167                 if (!writer) {
 168                         ret = -LTTNG_ERR_NOMEM;
 169                         goto end;
 170                 }
 171                 /* Open command element */
 172                 ret = mi_lttng_writer_command_open(writer,
 173                                 mi_lttng_element_command_metadata);
 174                 if (ret) {
 175                         ret = CMD_ERROR;
 176                         goto end;
 177                 }
 178
 179                 /* Open output element */
 180                 ret = mi_lttng_writer_open_element(writer,
 181                                 mi_lttng_element_command_output);
 182                 if (ret) {
 183                         ret = CMD_ERROR;
 184                         goto end;
 185                 }
 186         }
 187
 188         while ((opt = poptGetNextOpt(pc)) != -1) {
 189                 switch (opt) {
 190                 case OPT_HELP:
 191                         SHOW_HELP();
 192                         goto end;
 193                 case OPT_LIST_OPTIONS:
 194                         list_cmd_options(stdout, long_options);
 195                         goto end;
 196                 case OPT_LIST_COMMANDS:
 197                         list_commands(actions, stdout);
 198                         goto end;
 199                 default:
 200                         SHOW_HELP();
 201                         ret = CMD_UNDEFINED;
 202                         goto end;
 203                 }
 204         }
 205
 206         if (!opt_session_name) {
 207                 session_name = get_session_name();
 208                 if (session_name == NULL) {
 209                         ret = CMD_ERROR;
 210                         goto end;
 211                 }
 212         } else {
 213                 session_name = opt_session_name;
 214         }
 215
 216         command_ret = handle_command(poptGetArgs(pc));
 217         if (command_ret) {
 218                 switch (-command_ret) {
 219                 default:
 220                         ERR("%s", lttng_strerror(command_ret));
 221                         success = 0;
 222                         break;
 223                 }
 224         }
 225
 226         if (lttng_opt_mi) {
 227                 /* Close output element */
 228                 ret = mi_lttng_writer_close_element(writer);
 229                 if (ret) {
 230                         ret = CMD_ERROR;
 231                         goto end;
 232                 }
 233
 234                 /* Success ? */
 235                 ret = mi_lttng_writer_write_element_bool(writer,
 236                                 mi_lttng_element_command_success, success);
 237                 if (ret) {
 238                         ret = CMD_ERROR;
 239                         goto end;
 240                 }
 241
 242                 /* Command element close */
 243                 ret = mi_lttng_writer_command_close(writer);
 244                 if (ret) {
 245                         ret = CMD_ERROR;
 246                         goto end;
 247                 }
 248         }
 249
 250 end:
 251         /* Mi clean-up */
 252         if (writer && mi_lttng_writer_destroy(writer)) {
 253                 /* Preserve original error code */
 254                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 255         }
 256
 257         if (!opt_session_name) {
 258                 free(session_name);
 259         }
 260
 261         /* Overwrite ret if an error occurred during handle_command() */
 262         ret = command_ret ? command_ret : ret;
 263
 264         poptFreeContext(pc);
 265         return ret;
 266 }