ctdb/common/cmdline.c

   1 /*
   2    Command line processing
   3
   4    Copyright (C) Amitay Isaacs  2018
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "replace.h"
  21
  22 #include <popt.h>
  23 #include <talloc.h>
  24 #include <tevent.h>
  25
  26 #include "lib/util/debug.h"
  27
  28 #include "common/cmdline.h"
  29
  30 #define CMDLINE_MAX_LEN         80
  31
  32 struct cmdline_context {
  33         const char *prog;
  34         struct poptOption *options;
  35         struct cmdline_command *commands;
  36         int max_len;
  37         poptContext pc;
  38         int argc, arg0;
  39         const char **argv;
  40         struct cmdline_command *match_cmd;
  41 };
  42
  43 static bool cmdline_show_help = false;
  44
  45 static void cmdline_popt_help(poptContext pc,
  46                               enum poptCallbackReason reason,
  47                               struct poptOption *key,
  48                               const char *arg,
  49                               void *data)
  50 {
  51         if (key->shortName == 'h') {
  52                 cmdline_show_help = true;
  53         }
  54 }
  55
  56 struct poptOption cmdline_help_options[] = {
  57         { NULL, '\0', POPT_ARG_CALLBACK, cmdline_popt_help, 0, NULL, NULL },
  58         { "help", 'h', 0, NULL, 'h', "Show this help message", NULL },
  59         POPT_TABLEEND
  60 };
  61
  62 #define CMDLINE_HELP_OPTIONS \
  63         { NULL, '\0', POPT_ARG_INCLUDE_TABLE, cmdline_help_options, \
  64           0, "Help Options:", NULL }
  65
  66 static bool cmdline_option_check(struct poptOption *option)
  67 {
  68         if (option->longName == NULL) {
  69                 D_ERR("Option has no long name\n");
  70                 return false;
  71         }
  72
  73         if (option->argInfo != POPT_ARG_STRING &&
  74             option->argInfo != POPT_ARG_INT &&
  75             option->argInfo != POPT_ARG_LONG &&
  76             option->argInfo != POPT_ARG_VAL &&
  77             option->argInfo != POPT_ARG_FLOAT &&
  78             option->argInfo != POPT_ARG_DOUBLE) {
  79                 D_ERR("Option '%s' has unsupported type\n", option->longName);
  80                 return false;
  81         }
  82
  83         if (option->arg == NULL) {
  84                 D_ERR("Option '%s' has invalid arg\n", option->longName);
  85                 return false;
  86         }
  87
  88         if (option->descrip == NULL) {
  89                 D_ERR("Option '%s' has no help msg\n", option->longName);
  90                 return false;
  91         }
  92
  93         return true;
  94 }
  95
  96 static bool cmdline_options_check(struct poptOption *options)
  97 {
  98         int i;
  99         bool ok;
 100
 101         if (options == NULL) {
 102                 return true;
 103         }
 104
 105         i = 0;
 106         while (options[i].longName != NULL || options[i].shortName != '\0') {
 107                 ok = cmdline_option_check(&options[i]);
 108                 if (!ok) {
 109                         return false;
 110                 }
 111                 i++;
 112         }
 113
 114         return true;
 115 }
 116
 117 static int cmdline_options_define(TALLOC_CTX *mem_ctx,
 118                                   struct poptOption *user_options,
 119                                   struct poptOption **result)
 120 {
 121         struct poptOption *options;
 122         int count, i;
 123
 124         count = (user_options == NULL ? 2 : 3);
 125
 126         options = talloc_array(mem_ctx, struct poptOption, count);
 127         if (options == NULL) {
 128                 return ENOMEM;
 129         }
 130
 131         i = 0;
 132         options[i++] = (struct poptOption) CMDLINE_HELP_OPTIONS;
 133         if (user_options != NULL) {
 134                 options[i++] = (struct poptOption) {
 135                         .argInfo = POPT_ARG_INCLUDE_TABLE,
 136                         .arg = user_options,
 137                         .descrip = "Options:",
 138                 };
 139         }
 140         options[i++] = (struct poptOption) POPT_TABLEEND;
 141
 142         *result = options;
 143         return 0;
 144 }
 145
 146 static bool cmdline_command_check(struct cmdline_command *cmd, int *max_len)
 147 {
 148         size_t len;
 149
 150         if (cmd->name == NULL) {
 151                 return false;
 152         }
 153
 154         if (cmd->fn == NULL) {
 155                 D_ERR("Command '%s' has no implementation function\n",
 156                       cmd->name);
 157                 return false;
 158         }
 159
 160         if (cmd->msg_help == NULL) {
 161                 D_ERR("Command '%s' has no help msg\n", cmd->name);
 162                 return false;
 163         }
 164
 165         len = strlen(cmd->name);
 166         if (cmd->msg_args != NULL) {
 167                 len += strlen(cmd->msg_args);
 168         }
 169         if (len > CMDLINE_MAX_LEN) {
 170                 D_ERR("Command '%s' is too long (%zu)\n", cmd->name, len);
 171                 return false;
 172         }
 173
 174         if (len > *max_len) {
 175                 *max_len = (int)len;
 176         }
 177
 178         len = strlen(cmd->msg_help);
 179         if (len > CMDLINE_MAX_LEN) {
 180                 D_ERR("Command '%s' help too long (%zu)\n", cmd->name, len);
 181                 return false;
 182         }
 183
 184         return true;
 185 }
 186
 187 static bool cmdline_commands_check(struct cmdline_command *commands,
 188                                    int *max_len)
 189 {
 190         int i;
 191         bool ok;
 192
 193         if (commands == NULL) {
 194                 return false;
 195         }
 196
 197         for (i=0; commands[i].name != NULL; i++) {
 198                 ok = cmdline_command_check(&commands[i], max_len);
 199                 if (!ok) {
 200                         return false;
 201                 }
 202         }
 203
 204         return true;
 205 }
 206
 207 static int cmdline_context_destructor(struct cmdline_context *cmdline);
 208
 209 int cmdline_init(TALLOC_CTX *mem_ctx,
 210                  const char *prog,
 211                  struct poptOption *options,
 212                  struct cmdline_command *commands,
 213                  struct cmdline_context **result)
 214 {
 215         struct cmdline_context *cmdline;
 216         int ret, max_len = 0;
 217         bool ok;
 218
 219         if (prog == NULL) {
 220                 return EINVAL;
 221         }
 222
 223         ok = cmdline_options_check(options);
 224         if (!ok) {
 225                 return EINVAL;
 226         }
 227
 228         ok = cmdline_commands_check(commands, &max_len);
 229         if (!ok) {
 230                 return EINVAL;
 231         }
 232
 233         cmdline = talloc_zero(mem_ctx, struct  cmdline_context);
 234         if (cmdline == NULL) {
 235                 return ENOMEM;
 236         }
 237
 238         cmdline->prog = talloc_strdup(cmdline, prog);
 239         if (cmdline->prog == NULL) {
 240                 talloc_free(cmdline);
 241                 return ENOMEM;
 242         }
 243
 244         ret = cmdline_options_define(cmdline, options, &cmdline->options);
 245         if (ret != 0) {
 246                 talloc_free(cmdline);
 247                 return ret;
 248         }
 249         cmdline->commands = commands;
 250         cmdline->max_len = max_len;
 251
 252         cmdline->argc = 1;
 253         cmdline->argv = talloc_array(cmdline, const char *, 2);
 254         if (cmdline->argv == NULL) {
 255                 talloc_free(cmdline);
 256                 return ENOMEM;
 257         }
 258         cmdline->argv[0] = cmdline->prog;
 259         cmdline->argv[1] = NULL;
 260
 261         /* Dummy popt context for generating help */
 262         cmdline->pc = poptGetContext(cmdline->prog,
 263                                      cmdline->argc,
 264                                      cmdline->argv,
 265                                      cmdline->options,
 266                                      0);
 267         if (cmdline->pc == NULL) {
 268                 talloc_free(cmdline);
 269                 return ENOMEM;
 270         }
 271
 272         talloc_set_destructor(cmdline, cmdline_context_destructor);
 273
 274         *result = cmdline;
 275         return 0;
 276 }
 277
 278 static int cmdline_context_destructor(struct cmdline_context *cmdline)
 279 {
 280         if (cmdline->pc != NULL) {
 281                 poptFreeContext(cmdline->pc);
 282         }
 283
 284         return 0;
 285 }
 286
 287 static int cmdline_parse_options(struct cmdline_context *cmdline,
 288                                  int argc,
 289                                  const char **argv)
 290 {
 291         int opt;
 292
 293         if (cmdline->pc != NULL) {
 294                 poptFreeContext(cmdline->pc);
 295         }
 296
 297         cmdline->pc = poptGetContext(cmdline->prog,
 298                                      argc,
 299                                      argv,
 300                                      cmdline->options,
 301                                      0);
 302         if (cmdline->pc == NULL) {
 303                 return ENOMEM;
 304         }
 305
 306         while ((opt = poptGetNextOpt(cmdline->pc)) != -1) {
 307                 D_ERR("Invalid option %s: %s\n",
 308                       poptBadOption(cmdline->pc, 0),
 309                       poptStrerror(opt));
 310                 return EINVAL;
 311         }
 312
 313         /* Set up remaining arguments for commands */
 314         cmdline->argc = 0;
 315         cmdline->argv = poptGetArgs(cmdline->pc);
 316         if (cmdline->argv != NULL) {
 317                 while (cmdline->argv[cmdline->argc] != NULL) {
 318                         cmdline->argc++;
 319                 }
 320         }
 321
 322         return 0;
 323 }
 324
 325 static int cmdline_match(struct cmdline_context *cmdline)
 326 {
 327         int i;
 328
 329         if (cmdline->argc == 0 || cmdline->argv == NULL) {
 330                 cmdline->match_cmd = NULL;
 331                 return EINVAL;
 332         }
 333
 334         for (i=0; cmdline->commands[i].name != NULL; i++) {
 335                 struct cmdline_command *cmd;
 336                 char name[CMDLINE_MAX_LEN+1];
 337                 size_t len;
 338                 char *t, *str;
 339                 int n = 0;
 340                 bool match = false;
 341
 342                 cmd = &cmdline->commands[i];
 343                 len = strlcpy(name, cmd->name, sizeof(name));
 344                 if (len >= sizeof(name)) {
 345                         D_ERR("Skipping long command '%s'\n", cmd->name);
 346                         continue;
 347                 }
 348
 349                 str = name;
 350                 while ((t = strtok(str, " ")) != NULL) {
 351                         if (n >= cmdline->argc) {
 352                                 match = false;
 353                                 break;
 354                         }
 355                         if (cmdline->argv[n] == NULL) {
 356                                 match = false;
 357                                 break;
 358                         }
 359                         if (strcmp(cmdline->argv[n], t) == 0) {
 360                                 match = true;
 361                                 cmdline->arg0 = n+1;
 362                         } else {
 363                                 match = false;
 364                                 break;
 365                         }
 366
 367                         n += 1;
 368                         str = NULL;
 369                 }
 370
 371                 if (match) {
 372                         cmdline->match_cmd = cmd;
 373                         return 0;
 374                 }
 375         }
 376
 377         cmdline->match_cmd = NULL;
 378         return ENOENT;
 379 }
 380
 381 int cmdline_parse(struct cmdline_context *cmdline,
 382                   int argc,
 383                   const char **argv,
 384                   bool parse_options)
 385 {
 386         int ret;
 387
 388         if (argc < 2) {
 389                 return EINVAL;
 390         }
 391
 392         cmdline_show_help = false;
 393
 394         if (parse_options) {
 395                 ret = cmdline_parse_options(cmdline, argc, argv);
 396                 if (ret != 0) {
 397                         return ret;
 398                 }
 399         } else {
 400                 cmdline->argc = argc;
 401                 cmdline->argv = argv;
 402         }
 403
 404         ret = cmdline_match(cmdline);
 405         if (!cmdline_show_help && ret != 0) {
 406                 return ret;
 407         }
 408
 409         return 0;
 410 }
 411
 412 static void cmdline_usage_command(struct cmdline_context *cmdline,
 413                                   struct cmdline_command *cmd,
 414                                   bool print_all)
 415 {
 416         int len;
 417
 418         len = (int)strlen(cmd->name);
 419
 420         printf("  %s ", cmd->name);
 421         if (print_all) {
 422                 printf("%-*s",
 423                        cmdline->max_len-len,
 424                        cmd->msg_args == NULL ? "" : cmd->msg_args);
 425         } else {
 426                 printf("%s", cmd->msg_args == NULL ? "" : cmd->msg_args);
 427         }
 428         printf("     %s\n", cmd->msg_help);
 429 }
 430
 431 static void cmdline_usage_full(struct cmdline_context *cmdline)
 432 {
 433         int i;
 434
 435         poptSetOtherOptionHelp(cmdline->pc, "[<options>] <command> [<args>]");
 436         poptPrintHelp(cmdline->pc, stdout, 0);
 437
 438         printf("\nCommands:\n");
 439         for (i=0; cmdline->commands[i].name != NULL; i++) {
 440                 cmdline_usage_command(cmdline, &cmdline->commands[i], true);
 441
 442         }
 443 }
 444
 445 void cmdline_usage(struct cmdline_context *cmdline, const char *cmd_name)
 446 {
 447         struct cmdline_command *cmd = NULL;
 448         int i;
 449
 450         if (cmd_name == NULL) {
 451                 cmdline_usage_full(cmdline);
 452                 return;
 453         }
 454
 455         for (i=0; cmdline->commands[i].name != NULL; i++) {
 456                 if (strcmp(cmdline->commands[i].name, cmd_name) == 0) {
 457                         cmd = &cmdline->commands[i];
 458                         break;
 459                 }
 460         }
 461
 462         if (cmd == NULL) {
 463                 cmdline_usage_full(cmdline);
 464                 return;
 465         }
 466
 467         poptSetOtherOptionHelp(cmdline->pc, "<command> [<args>]");
 468         poptPrintUsage(cmdline->pc, stdout, 0);
 469
 470         printf("\n");
 471         cmdline_usage_command(cmdline, cmd, false);
 472 }
 473
 474 int cmdline_run(struct cmdline_context *cmdline,
 475                 void *private_data,
 476                 int *result)
 477 {
 478         struct cmdline_command *cmd = cmdline->match_cmd;
 479         TALLOC_CTX *tmp_ctx;
 480         int ret;
 481
 482         if (cmdline_show_help) {
 483                 const char *name = NULL;
 484
 485                 if (cmd != NULL) {
 486                         name = cmdline->match_cmd->name;
 487                 }
 488
 489                 cmdline_usage(cmdline, name);
 490
 491                 if (result != NULL) {
 492                         *result = 0;
 493                 }
 494                 return EAGAIN;
 495         }
 496
 497         if (cmd == NULL) {
 498                 return ENOENT;
 499         }
 500
 501         tmp_ctx = talloc_new(cmdline);
 502         if (tmp_ctx == NULL) {
 503                 return ENOMEM;
 504         }
 505
 506         ret = cmd->fn(tmp_ctx,
 507                       cmdline->argc - cmdline->arg0,
 508                       &cmdline->argv[cmdline->arg0],
 509                       private_data);
 510
 511         talloc_free(tmp_ctx);
 512
 513         if (result != NULL) {
 514                 *result = ret;
 515         }
 516         return 0;
 517 }