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         ret = lttng_metadata_regenerate(session_name);
  79         if (ret == 0) {
  80                 MSG("Metadata successfully regenerated for session %s", session_name);
  81         }
  82         return ret;
  83 }
  84
  85 static int handle_command(const char **argv)
  86 {
  87         struct cmd_struct *cmd;
  88         int ret = CMD_SUCCESS, i = 0, argc, command_ret = CMD_SUCCESS;
  89
  90         if (argv == NULL) {
  91                 SHOW_HELP();
  92                 command_ret = CMD_ERROR;
  93                 goto end;
  94         }
  95
  96         argc = count_arguments(argv);
  97
  98         cmd = &actions[i];
  99         while (cmd->func != NULL) {
 100                 /* Find command */
 101                 if (strcmp(argv[0], cmd->name) == 0) {
 102                         if (lttng_opt_mi) {
 103                                 /* Action element */
 104                                 ret = mi_lttng_writer_open_element(writer,
 105                                                 mi_lttng_element_command_metadata_action);
 106                                 if (ret) {
 107                                         ret = CMD_ERROR;
 108                                         goto end;
 109                                 }
 110
 111                                 /* Name of the action */
 112                                 ret = mi_lttng_writer_write_element_string(writer,
 113                                                 config_element_name, argv[0]);
 114                                 if (ret) {
 115                                         ret = CMD_ERROR;
 116                                         goto end;
 117                                 }
 118                         }
 119                         command_ret = cmd->func(argc, argv);
 120                         if (lttng_opt_mi) {
 121                                 /* Close output and action element */
 122                                 ret = mi_lttng_writer_close_element(writer);
 123                                 if (ret) {
 124                                         ret = CMD_ERROR;
 125                                         goto end;
 126                                 }
 127                         }
 128                         goto end;
 129                 }
 130
 131                 cmd = &actions[i++];
 132         }
 133
 134         ret = CMD_UNDEFINED;
 135
 136 end:
 137         /* Overwrite ret if an error occurred in cmd->func() */
 138         ret = command_ret ? command_ret : ret;
 139         return ret;
 140 }
 141
 142 /*
 143  * Metadata command handling.
 144  */
 145 int cmd_metadata(int argc, const char **argv)
 146 {
 147         int opt, ret = CMD_SUCCESS, command_ret = CMD_SUCCESS, success = 1;
 148         static poptContext pc;
 149
 150         if (argc < 1) {
 151                 SHOW_HELP();
 152                 ret = CMD_ERROR;
 153                 goto end;
 154         }
 155
 156         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 157         poptReadDefaultConfig(pc, 0);
 158
 159         if (lttng_opt_mi) {
 160                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 161                 if (!writer) {
 162                         ret = -LTTNG_ERR_NOMEM;
 163                         goto end;
 164                 }
 165                 /* Open command element */
 166                 ret = mi_lttng_writer_command_open(writer,
 167                                 mi_lttng_element_command_metadata);
 168                 if (ret) {
 169                         ret = CMD_ERROR;
 170                         goto end;
 171                 }
 172
 173                 /* Open output element */
 174                 ret = mi_lttng_writer_open_element(writer,
 175                                 mi_lttng_element_command_output);
 176                 if (ret) {
 177                         ret = CMD_ERROR;
 178                         goto end;
 179                 }
 180         }
 181
 182         while ((opt = poptGetNextOpt(pc)) != -1) {
 183                 switch (opt) {
 184                 case OPT_HELP:
 185                         SHOW_HELP();
 186                         goto end;
 187                 case OPT_LIST_OPTIONS:
 188                         list_cmd_options(stdout, long_options);
 189                         goto end;
 190                 case OPT_LIST_COMMANDS:
 191                         list_commands(actions, stdout);
 192                         goto end;
 193                 default:
 194                         SHOW_HELP();
 195                         ret = CMD_UNDEFINED;
 196                         goto end;
 197                 }
 198         }
 199
 200         if (!opt_session_name) {
 201                 session_name = get_session_name();
 202                 if (session_name == NULL) {
 203                         ret = CMD_ERROR;
 204                         goto end;
 205                 }
 206         } else {
 207                 session_name = opt_session_name;
 208         }
 209
 210         command_ret = handle_command(poptGetArgs(pc));
 211         if (command_ret) {
 212                 switch (-command_ret) {
 213                 default:
 214                         ERR("%s", lttng_strerror(command_ret));
 215                         success = 0;
 216                         break;
 217                 }
 218         }
 219
 220         if (lttng_opt_mi) {
 221                 /* Close output element */
 222                 ret = mi_lttng_writer_close_element(writer);
 223                 if (ret) {
 224                         ret = CMD_ERROR;
 225                         goto end;
 226                 }
 227
 228                 /* Success ? */
 229                 ret = mi_lttng_writer_write_element_bool(writer,
 230                                 mi_lttng_element_command_success, success);
 231                 if (ret) {
 232                         ret = CMD_ERROR;
 233                         goto end;
 234                 }
 235
 236                 /* Command element close */
 237                 ret = mi_lttng_writer_command_close(writer);
 238                 if (ret) {
 239                         ret = CMD_ERROR;
 240                         goto end;
 241                 }
 242         }
 243
 244 end:
 245         /* Mi clean-up */
 246         if (writer && mi_lttng_writer_destroy(writer)) {
 247                 /* Preserve original error code */
 248                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 249         }
 250
 251         if (!opt_session_name) {
 252                 free(session_name);
 253         }
 254
 255         /* Overwrite ret if an error occurred during handle_command() */
 256         ret = command_ret ? command_ret : ret;
 257
 258         poptFreeContext(pc);
 259         return ret;
 260 }