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 #ifdef LTTNG_EMBED_HELP
  37 static const char help_msg[] =
  38 #include <lttng-metadata.1.h>
  39 ;
  40 #endif
  41
  42 enum {
  43         OPT_HELP = 1,
  44         OPT_LIST_OPTIONS,
  45         OPT_LIST_COMMANDS,
  46 };
  47
  48 static struct mi_writer *writer;
  49
  50 static struct poptOption long_options[] = {
  51         /* { longName, shortName, argInfo, argPtr, value, descrip, argDesc, } */
  52         { "help",               'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0, },
  53         { "session",            's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  54         { "list-options",       0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, 0, 0, },
  55         { "list-commands",      0, POPT_ARG_NONE, NULL, OPT_LIST_COMMANDS},
  56         { 0, 0, 0, 0, 0, 0, 0, },
  57 };
  58
  59 static struct cmd_struct actions[] = {
  60         { "regenerate", metadata_regenerate },
  61         { NULL, NULL }  /* Array closure */
  62 };
  63
  64 /*
  65  * Count and return the number of arguments in argv.
  66  */
  67 static int count_arguments(const char **argv)
  68 {
  69         int i = 0;
  70
  71         assert(argv);
  72
  73         while (argv[i] != NULL) {
  74                 i++;
  75         }
  76
  77         return i;
  78 }
  79
  80 static int metadata_regenerate(int argc, const char **argv)
  81 {
  82         int ret;
  83
  84         if (argc > 1) {
  85                 ret = -LTTNG_ERR_INVALID;
  86                 goto end;
  87         }
  88         ret = lttng_regenerate_metadata(session_name);
  89         if (ret == 0) {
  90                 MSG("Metadata successfully regenerated for session %s", session_name);
  91         }
  92
  93 end:
  94         return ret;
  95 }
  96
  97 static int handle_command(const char **argv)
  98 {
  99         struct cmd_struct *cmd;
 100         int ret = CMD_SUCCESS, i = 0, argc, command_ret = CMD_SUCCESS;
 101
 102         if (argv == NULL) {
 103                 ERR("argv is null");
 104                 command_ret = CMD_ERROR;
 105                 goto end;
 106         }
 107
 108         argc = count_arguments(argv);
 109
 110         cmd = &actions[i];
 111         while (cmd->func != NULL) {
 112                 /* Find command */
 113                 if (strcmp(argv[0], cmd->name) == 0) {
 114                         if (lttng_opt_mi) {
 115                                 /* Action element */
 116                                 ret = mi_lttng_writer_open_element(writer,
 117                                                 mi_lttng_element_command_metadata_action);
 118                                 if (ret) {
 119                                         ret = CMD_ERROR;
 120                                         goto end;
 121                                 }
 122
 123                                 /* Name of the action */
 124                                 ret = mi_lttng_writer_write_element_string(writer,
 125                                                 config_element_name, argv[0]);
 126                                 if (ret) {
 127                                         ret = CMD_ERROR;
 128                                         goto end;
 129                                 }
 130                         }
 131                         command_ret = cmd->func(argc, argv);
 132                         if (lttng_opt_mi) {
 133                                 /* Close output and action element */
 134                                 ret = mi_lttng_writer_close_element(writer);
 135                                 if (ret) {
 136                                         ret = CMD_ERROR;
 137                                         goto end;
 138                                 }
 139                         }
 140                         goto end;
 141                 }
 142
 143                 cmd = &actions[i++];
 144         }
 145
 146         ret = CMD_UNDEFINED;
 147
 148 end:
 149         /* Overwrite ret if an error occurred in cmd->func() */
 150         ret = command_ret ? command_ret : ret;
 151         return ret;
 152 }
 153
 154 /*
 155  * Metadata command handling.
 156  */
 157 int cmd_metadata(int argc, const char **argv)
 158 {
 159         int opt, ret = CMD_SUCCESS, command_ret = CMD_SUCCESS, success = 1;
 160         static poptContext pc;
 161
 162         if (argc < 1) {
 163                 SHOW_HELP();
 164                 ret = CMD_ERROR;
 165                 goto end;
 166         }
 167
 168         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 169         poptReadDefaultConfig(pc, 0);
 170
 171         if (lttng_opt_mi) {
 172                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 173                 if (!writer) {
 174                         ret = -LTTNG_ERR_NOMEM;
 175                         goto end;
 176                 }
 177                 /* Open command element */
 178                 ret = mi_lttng_writer_command_open(writer,
 179                                 mi_lttng_element_command_metadata);
 180                 if (ret) {
 181                         ret = CMD_ERROR;
 182                         goto end;
 183                 }
 184
 185                 /* Open output element */
 186                 ret = mi_lttng_writer_open_element(writer,
 187                                 mi_lttng_element_command_output);
 188                 if (ret) {
 189                         ret = CMD_ERROR;
 190                         goto end;
 191                 }
 192         }
 193
 194         while ((opt = poptGetNextOpt(pc)) != -1) {
 195                 switch (opt) {
 196                 case OPT_HELP:
 197                         SHOW_HELP();
 198                         goto end;
 199                 case OPT_LIST_OPTIONS:
 200                         list_cmd_options(stdout, long_options);
 201                         goto end;
 202                 case OPT_LIST_COMMANDS:
 203                         list_commands(actions, stdout);
 204                         goto end;
 205                 default:
 206                         SHOW_HELP();
 207                         ret = CMD_UNDEFINED;
 208                         goto end;
 209                 }
 210         }
 211
 212         if (!opt_session_name) {
 213                 session_name = get_session_name();
 214                 if (session_name == NULL) {
 215                         ret = CMD_ERROR;
 216                         goto end;
 217                 }
 218         } else {
 219                 session_name = opt_session_name;
 220         }
 221
 222         command_ret = handle_command(poptGetArgs(pc));
 223         if (command_ret) {
 224                 switch (-command_ret) {
 225                 default:
 226                         ERR("%s", lttng_strerror(command_ret));
 227                         success = 0;
 228                         break;
 229                 }
 230         }
 231
 232         if (lttng_opt_mi) {
 233                 /* Close output element */
 234                 ret = mi_lttng_writer_close_element(writer);
 235                 if (ret) {
 236                         ret = CMD_ERROR;
 237                         goto end;
 238                 }
 239
 240                 /* Success ? */
 241                 ret = mi_lttng_writer_write_element_bool(writer,
 242                                 mi_lttng_element_command_success, success);
 243                 if (ret) {
 244                         ret = CMD_ERROR;
 245                         goto end;
 246                 }
 247
 248                 /* Command element close */
 249                 ret = mi_lttng_writer_command_close(writer);
 250                 if (ret) {
 251                         ret = CMD_ERROR;
 252                         goto end;
 253                 }
 254         }
 255
 256 end:
 257         /* Mi clean-up */
 258         if (writer && mi_lttng_writer_destroy(writer)) {
 259                 /* Preserve original error code */
 260                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 261         }
 262
 263         if (!opt_session_name) {
 264                 free(session_name);
 265         }
 266
 267         /* Overwrite ret if an error occurred during handle_command() */
 268         ret = command_ret ? command_ret : ret;
 269
 270         poptFreeContext(pc);
 271         return ret;
 272 }