src/bin/lttng/commands/metadata.cpp

   1 /*
   2  * Copyright (C) 2015 Julien Desfossez <jdesfossez@efficios.com>
   3  *
   4  * SPDX-License-Identifier: GPL-2.0-only
   5  *
   6  */
   7
   8 #define _LGPL_SOURCE
   9 #include <ctype.h>
  10 #include <popt.h>
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <unistd.h>
  15
  16 #include <common/mi-lttng.h>
  17
  18 #include "../command.h"
  19
  20 static char *opt_session_name;
  21 static char *session_name = NULL;
  22
  23 static int metadata_regenerate(int argc, const char **argv);
  24
  25 #ifdef LTTNG_EMBED_HELP
  26 static const char help_msg[] =
  27 #include <lttng-metadata.1.h>
  28 ;
  29 #endif
  30
  31 enum {
  32         OPT_HELP = 1,
  33         OPT_LIST_OPTIONS,
  34         OPT_LIST_COMMANDS,
  35 };
  36
  37 static struct mi_writer *writer;
  38
  39 static struct poptOption long_options[] = {
  40         /* { longName, shortName, argInfo, argPtr, value, descrip, argDesc, } */
  41         { "help",               'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0, },
  42         { "session",            's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  43         { "list-options",       0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, 0, 0, },
  44         { "list-commands",      0, POPT_ARG_NONE, NULL, OPT_LIST_COMMANDS},
  45         { 0, 0, 0, 0, 0, 0, 0, },
  46 };
  47
  48 static struct cmd_struct actions[] = {
  49         { "regenerate", metadata_regenerate },
  50         { NULL, NULL }  /* Array closure */
  51 };
  52
  53 /*
  54  * Count and return the number of arguments in argv.
  55  */
  56 static int count_arguments(const char **argv)
  57 {
  58         int i = 0;
  59
  60         LTTNG_ASSERT(argv);
  61
  62         while (argv[i] != NULL) {
  63                 i++;
  64         }
  65
  66         return i;
  67 }
  68
  69 static int metadata_regenerate(int argc, const char **argv)
  70 {
  71         int ret;
  72
  73         if (argc > 1) {
  74                 ret = CMD_UNDEFINED;
  75                 goto end;
  76         }
  77         ret = lttng_regenerate_metadata(session_name);
  78         if (ret == 0) {
  79                 MSG("Metadata successfully regenerated for session %s", session_name);
  80         } else {
  81                 ERR("%s", lttng_strerror(ret));
  82         }
  83
  84 end:
  85         return ret;
  86 }
  87
  88 static int handle_command(const char **argv)
  89 {
  90         struct cmd_struct *cmd;
  91         int ret = CMD_SUCCESS, i = 0, argc, command_ret = CMD_SUCCESS;
  92
  93         if (argv == NULL) {
  94                 ERR("No action specified for metadata command.");
  95                 ret = CMD_ERROR;
  96                 goto end;
  97         }
  98
  99         argc = count_arguments(argv);
 100         LTTNG_ASSERT(argc >= 1);
 101
 102         cmd = &actions[i];
 103         while (cmd->func != NULL) {
 104                 /* Find command */
 105                 if (strcmp(argv[0], cmd->name) == 0) {
 106                         if (lttng_opt_mi) {
 107                                 /* Action element */
 108                                 ret = mi_lttng_writer_open_element(writer,
 109                                                 mi_lttng_element_command_metadata_action);
 110                                 if (ret) {
 111                                         ret = CMD_ERROR;
 112                                         goto end;
 113                                 }
 114
 115                                 /* Name of the action */
 116                                 ret = mi_lttng_writer_write_element_string(writer,
 117                                                 config_element_name, argv[0]);
 118                                 if (ret) {
 119                                         ret = CMD_ERROR;
 120                                         goto end;
 121                                 }
 122                         }
 123                         command_ret = cmd->func(argc, argv);
 124                         if (lttng_opt_mi) {
 125                                 /* Close output and action element */
 126                                 ret = mi_lttng_writer_close_element(writer);
 127                                 if (ret) {
 128                                         ret = CMD_ERROR;
 129                                         goto end;
 130                                 }
 131                         }
 132                         goto end;
 133                 }
 134
 135                 cmd = &actions[i++];
 136         }
 137
 138         ret = CMD_UNDEFINED;
 139
 140 end:
 141         /* Overwrite ret if an error occurred in cmd->func() */
 142         ret = command_ret ? command_ret : ret;
 143         return ret;
 144 }
 145
 146 /*
 147  * Metadata command handling.
 148  */
 149 int cmd_metadata(int argc, const char **argv)
 150 {
 151         int opt, ret = CMD_SUCCESS, command_ret = CMD_SUCCESS, success = 1;
 152         static poptContext pc;
 153
 154         if (argc < 1) {
 155                 SHOW_HELP();
 156                 ret = CMD_ERROR;
 157                 goto end;
 158         }
 159
 160         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 161         poptReadDefaultConfig(pc, 0);
 162
 163         if (lttng_opt_mi) {
 164                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 165                 if (!writer) {
 166                         ret = -LTTNG_ERR_NOMEM;
 167                         goto end;
 168                 }
 169                 /* Open command element */
 170                 ret = mi_lttng_writer_command_open(writer,
 171                                 mi_lttng_element_command_metadata);
 172                 if (ret) {
 173                         ret = CMD_ERROR;
 174                         goto end;
 175                 }
 176
 177                 /* Open output element */
 178                 ret = mi_lttng_writer_open_element(writer,
 179                                 mi_lttng_element_command_output);
 180                 if (ret) {
 181                         ret = CMD_ERROR;
 182                         goto end;
 183                 }
 184         }
 185
 186         while ((opt = poptGetNextOpt(pc)) != -1) {
 187                 switch (opt) {
 188                 case OPT_HELP:
 189                         SHOW_HELP();
 190                         goto end;
 191                 case OPT_LIST_OPTIONS:
 192                         list_cmd_options(stdout, long_options);
 193                         goto end;
 194                 case OPT_LIST_COMMANDS:
 195                         list_commands(actions, stdout);
 196                         goto end;
 197                 default:
 198                         SHOW_HELP();
 199                         ret = CMD_UNDEFINED;
 200                         goto end;
 201                 }
 202         }
 203
 204         if (!opt_session_name) {
 205                 session_name = get_session_name();
 206                 if (session_name == NULL) {
 207                         ret = CMD_ERROR;
 208                         goto end;
 209                 }
 210         } else {
 211                 session_name = opt_session_name;
 212         }
 213
 214         command_ret = handle_command(poptGetArgs(pc));
 215         if (command_ret) {
 216                 success = 0;
 217         }
 218
 219         if (lttng_opt_mi) {
 220                 /* Close output element */
 221                 ret = mi_lttng_writer_close_element(writer);
 222                 if (ret) {
 223                         ret = CMD_ERROR;
 224                         goto end;
 225                 }
 226
 227                 /* Success ? */
 228                 ret = mi_lttng_writer_write_element_bool(writer,
 229                                 mi_lttng_element_command_success, success);
 230                 if (ret) {
 231                         ret = CMD_ERROR;
 232                         goto end;
 233                 }
 234
 235                 /* Command element close */
 236                 ret = mi_lttng_writer_command_close(writer);
 237                 if (ret) {
 238                         ret = CMD_ERROR;
 239                         goto end;
 240                 }
 241         }
 242
 243 end:
 244         /* Mi clean-up */
 245         if (writer && mi_lttng_writer_destroy(writer)) {
 246                 /* Preserve original error code */
 247                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 248         }
 249
 250         if (!opt_session_name) {
 251                 free(session_name);
 252         }
 253
 254         /* Overwrite ret if an error occurred during handle_command() */
 255         ret = command_ret ? command_ret : ret;
 256
 257         poptFreeContext(pc);
 258         return ret;
 259 }