src/helper/command.c

   1 /***************************************************************************
   2  *   Copyright (C) 2005 by Dominic Rath                                    *
   3  *   Dominic.Rath@gmx.de                                                   *
   4  *                                                                         *
   5  *   part of this file is taken from libcli (libcli.sourceforge.net)       *
   6  *   Copyright (C) David Parrish (david@dparrish.com)                      *
   7  *                                                                         *
   8  *   This program is free software; you can redistribute it and/or modify  *
   9  *   it under the terms of the GNU General Public License as published by  *
  10  *   the Free Software Foundation; either version 2 of the License, or     *
  11  *   (at your option) any later version.                                   *
  12  *                                                                         *
  13  *   This program is distributed in the hope that it will be useful,       *
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  16  *   GNU General Public License for more details.                          *
  17  *                                                                         *
  18  *   You should have received a copy of the GNU General Public License     *
  19  *   along with this program; if not, write to the                         *
  20  *   Free Software Foundation, Inc.,                                       *
  21  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  22  ***************************************************************************/
  23 #include "command.h"
  24
  25 #include "log.h"
  26
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <ctype.h>
  30 #include <stdarg.h>
  31 #include <stdio.h>
  32 #include <unistd.h>
  33
  34 int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  35
  36 int build_unique_lengths(command_context_t *context, command_t *commands)
  37 {
  38         command_t *c, *p;
  39
  40         /* iterate through all commands */
  41         for (c = commands; c; c = c->next)
  42         {
  43                 /* find out how many characters are required to uniquely identify a command */
  44                 for (c->unique_len = 1; c->unique_len <= strlen(c->name); c->unique_len++)
  45                 {
  46                         int foundmatch = 0;
  47
  48                         /* for every command, see if the current length is enough */
  49                         for (p = commands; p; p = p->next)
  50                         {
  51                                 /* ignore the command itself */
  52                                 if (c == p)
  53                                         continue;
  54
  55                                 /* compare commands up to the current length */
  56                                 if (strncmp(p->name, c->name, c->unique_len) == 0)
  57                                         foundmatch++;
  58                         }
  59
  60                         /* when none of the commands matched, we've found the minimum length required */
  61                         if (!foundmatch)
  62                                 break;
  63                 }
  64
  65                 /* if the current command has children, build the unique lengths for them */
  66                 if (c->children)
  67                         build_unique_lengths(context, c->children);
  68         }
  69
  70         return ERROR_OK;
  71 }
  72
  73 command_t* register_command(command_context_t *context, command_t *parent, char *name, int (*handler)(struct command_context_s *context, char* name, char** args, int argc), enum command_mode mode, char *help)
  74 {
  75         command_t *c, *p;
  76
  77         if (!context || !name)
  78                 return NULL;
  79
  80         c = malloc(sizeof(command_t));
  81
  82         c->name = strdup(name);
  83         c->parent = parent;
  84         c->children = NULL;
  85         c->handler = handler;
  86         c->mode = mode;
  87         if (help)
  88                 c->help = strdup(help);
  89         else
  90                 c->help = NULL;
  91         c->unique_len = 0;
  92         c->next = NULL;
  93
  94         /* place command in tree */
  95         if (parent)
  96         {
  97                 if (parent->children)
  98                 {
  99                         /* find last child */
 100                         for (p = parent->children; p && p->next; p = p->next);
 101                         if (p)
 102                                 p->next = c;
 103                 }
 104                 else
 105                 {
 106                         parent->children = c;
 107                 }
 108         }
 109         else
 110         {
 111                 if (context->commands)
 112                 {
 113                         /* find last command */
 114                         for (p = context->commands; p && p->next; p = p->next);
 115                         if (p)
 116                                 p->next = c;
 117                 }
 118                 else
 119                 {
 120                         context->commands = c;
 121                 }
 122         }
 123
 124         /* update unique lengths */
 125         build_unique_lengths(context, (parent) ? parent : context->commands);
 126
 127         return c;
 128 }
 129
 130 int unregister_command(command_context_t *context, char *name)
 131 {
 132         command_t *c, *p = NULL, *c2;
 133
 134         if ((!context) || (!name))
 135                 return ERROR_INVALID_ARGUMENTS;
 136
 137         /* find command */
 138         for (c = context->commands; c; c = c->next)
 139         {
 140                 if (strcmp(name, c->name) == 0)
 141                 {
 142                         /* unlink command */
 143                         if (p)
 144                         {
 145                                 p->next = c->next;
 146                         }
 147                         else
 148                         {
 149                                 context->commands = c->next;
 150                         }
 151
 152                         /* unregister children */
 153                         if (c->children)
 154                         {
 155                                 for (c2 = c->children; c2; c2 = c2->next)
 156                                 {
 157                                         free(c2->name);
 158                                         if (c2->help)
 159                                                 free(c2->help);
 160                                         free(c2);
 161                                 }
 162                         }
 163
 164                         /* delete command */
 165                         free(c->name);
 166                         if (c->help)
 167                                 free(c->help);
 168                         free(c);
 169                 }
 170
 171                 /* remember the last command for unlinking */
 172                 p = c;
 173         }
 174
 175         return ERROR_OK;
 176 }
 177
 178 int parse_line(char *line, char *words[], int max_words)
 179 {
 180         int nwords = 0;
 181         char *p = line;
 182         char *word_start = line;
 183         int inquote = 0;
 184
 185         while (nwords < max_words - 1)
 186         {
 187                 /* check if we reached
 188                  * a terminating NUL
 189                  * a matching closing quote character " or '
 190                  * we're inside a word but not a quote, and the current character is whitespace
 191                  */
 192                 if (!*p || *p == inquote || (word_start && !inquote && isspace(*p)))
 193                 {
 194                         /* we're inside a word or quote, and reached its end*/
 195                         if (word_start)
 196                         {
 197                                 int len = p - word_start;
 198
 199                                 /* copy the word */
 200                                 memcpy(words[nwords] = malloc(len + 1), word_start, len);
 201                                 /* add terminating NUL */
 202                                 words[nwords++][len] = 0;
 203                         }
 204
 205                         /* we're done parsing the line */
 206                         if (!*p)
 207                                 break;
 208
 209                         /* skip over trailing quote or whitespace*/
 210                         if (inquote || isspace(*p))
 211                                 p++;
 212
 213                         inquote = 0;
 214                         word_start = 0;
 215                 }
 216                 else if (*p == '"' || *p == '\'')
 217                 {
 218                         /* we've reached the beginning of a quote */
 219                         inquote = *p++;
 220                         word_start = p;
 221                 }
 222                 else
 223                 {
 224                         /* we've reached the beginning of a new word */
 225                         if (!word_start)
 226                                 word_start = p;
 227
 228                         /* normal character, skip */
 229                         p++;
 230                 }
 231         }
 232
 233         return nwords;
 234 }
 235
 236 void command_print(command_context_t *context, char *format, ...)
 237 {
 238         va_list ap;
 239         char *buffer = NULL;
 240         int n, size = 0;
 241         char *p;
 242
 243         va_start(ap, format);
 244
 245         /* process format string */
 246         /* TODO: possible bug. va_list is undefined after the first call to vsnprintf */
 247         while (!buffer || (n = vsnprintf(buffer, size, format, ap)) >= size)
 248         {
 249                 /* increase buffer until it fits the whole string */
 250                 if (!(p = realloc(buffer, size += 4096)))
 251                         return;
 252
 253                 buffer = p;
 254         }
 255
 256         /* vsnprintf failed */
 257         if (n < 0)
 258                 return;
 259
 260         p = buffer;
 261
 262         /* process lines in buffer */
 263         do {
 264                 char *next = strchr(p, '\n');
 265
 266                 if (next)
 267                         *next++ = 0;
 268
 269                 if (context->output_handler)
 270                         context->output_handler(context, p);
 271
 272                 p = next;
 273         } while (p);
 274
 275         if (buffer)
 276                 free(buffer);
 277
 278         va_end(ap);
 279 }
 280
 281 int find_and_run_command(command_context_t *context, command_t *commands, char *words[], int num_words, int start_word)
 282 {
 283         command_t *c;
 284
 285         for (c = commands; c; c = c->next)
 286         {
 287                 if (strncasecmp(c->name, words[start_word], c->unique_len))
 288                         continue;
 289
 290                 if (strncasecmp(c->name, words[start_word], strlen(words[start_word])))
 291                         continue;
 292
 293                 if ((c->mode == context->mode) || (c->mode == COMMAND_ANY))
 294                 {
 295                         if (!c->children)
 296                         {
 297                                 if (!c->handler)
 298                                 {
 299                                         command_print(context, "No handler for command");
 300                                         break;
 301                                 }
 302                                 else
 303                                 {
 304                                         return c->handler(context, c->name, words + start_word + 1, num_words - start_word - 1);
 305                                 }
 306                         }
 307                         else
 308                         {
 309                                 if (start_word == num_words - 1)
 310                                 {
 311                                         command_print(context, "Incomplete command");
 312                                         break;
 313                                 }
 314                                 return find_and_run_command(context, c->children, words, num_words, start_word + 1);
 315                         }
 316                 }
 317         }
 318
 319         command_print(context, "Command %s not found", words[start_word]);
 320         return ERROR_OK;
 321 }
 322
 323 int command_run_line(command_context_t *context, char *line)
 324 {
 325         int nwords;
 326         char *words[128] = {0};
 327         int retval;
 328         int i;
 329
 330         if ((!context) || (!line))
 331                 return ERROR_INVALID_ARGUMENTS;
 332
 333         /* skip preceding whitespace */
 334         while (isspace(*line))
 335                 line++;
 336
 337         /* empty line, ignore */
 338         if (!*line)
 339                 return ERROR_OK;
 340
 341         if (context->echo)
 342         {
 343                 command_print(context, "%s", line);
 344         }
 345
 346         nwords = parse_line(line, words, sizeof(words) / sizeof(words[0]));
 347
 348         if (nwords > 0)
 349                 retval = find_and_run_command(context, context->commands, words, nwords, 0);
 350         else
 351                 return ERROR_INVALID_ARGUMENTS;
 352
 353         for (i = 0; i < nwords; i++)
 354                 free(words[i]);
 355
 356         return retval;
 357 }
 358
 359 int command_run_file(command_context_t *context, FILE *file, enum command_mode mode)
 360 {
 361         int retval;
 362         int old_command_mode;
 363         char buffer[4096];
 364
 365         old_command_mode = context->mode;
 366         context->mode = mode;
 367
 368         while (fgets(buffer, 4096, file))
 369         {
 370                 char *p;
 371                 char *cmd, *end;
 372
 373                 /* stop processing line after a comment (#, !) or a LF, CR were encountered */
 374                 if ((p = strpbrk(buffer, "#!\r\n")))
 375                         *p = 0;
 376
 377                 /* skip over leading whitespace */
 378                 cmd = buffer;
 379                 while (isspace(*cmd))
 380                         cmd++;
 381
 382                 /* empty (all whitespace) line? */
 383                 if (!*cmd)
 384                         continue;
 385
 386                 /* search the end of the current line, ignore trailing whitespace */
 387                 for (p = end = cmd; *p; p++)
 388                         if (!isspace(*p))
 389                                 end = p;
 390
 391                 /* terminate end */
 392                 *++end = 0;
 393                 if (strcasecmp(cmd, "quit") == 0)
 394                         break;
 395
 396                 /* run line */
 397                 if (command_run_line(context, cmd) == ERROR_COMMAND_CLOSE_CONNECTION)
 398                         break;
 399         }
 400
 401         context->mode = old_command_mode;
 402
 403         return retval;
 404 }
 405
 406 void command_print_help_line(command_context_t* context, struct command_s *command, int indent)
 407 {
 408         command_t *c;
 409         char indents[32] = {0};
 410         char *help = "no help available";
 411         char name_buf[64];
 412         int i;
 413
 414         for (i = 0; i < indent; i+=2)
 415         {
 416                 indents[i*2] = ' ';
 417                 indents[i*2+1] = '-';
 418         }
 419         indents[i*2] = 0;
 420
 421         if ((command->mode == COMMAND_EXEC) || (command->mode == COMMAND_ANY))
 422         {
 423                 if (command->help)
 424                         help = command->help;
 425
 426                 snprintf(name_buf, 64, command->name);
 427                 strncat(name_buf, indents, 64);
 428                 command_print(context, "%20s\t%s", name_buf, help);
 429         }
 430
 431         if (command->children)
 432         {
 433                 for (c = command->children; c; c = c->next)
 434                 {
 435                         command_print_help_line(context, c, indent + 1);
 436                 }
 437         }
 438 }
 439
 440 int command_print_help(command_context_t* context, char* name, char** args, int argc)
 441 {
 442         command_t *c;
 443
 444         for (c = context->commands; c; c = c->next)
 445         {
 446                 if (argc == 1)
 447                 {
 448                          if (strncasecmp(c->name, args[0], c->unique_len))
 449                                  continue;
 450
 451                          if (strncasecmp(c->name, args[0], strlen(args[0])))
 452                                  continue;
 453                 }
 454
 455                 command_print_help_line(context, c, 0);
 456         }
 457
 458         return ERROR_OK;
 459 }
 460
 461 void command_set_output_handler(command_context_t* context, int (*output_handler)(struct command_context_s *context, char* line), void *priv)
 462 {
 463         context->output_handler = output_handler;
 464         context->output_handler_priv = priv;
 465 }
 466
 467 command_context_t* copy_command_context(command_context_t* context)
 468 {
 469         command_context_t* copy_context = malloc(sizeof(command_context_t));
 470
 471         *copy_context = *context;
 472
 473         return copy_context;
 474 }
 475
 476 int command_done(command_context_t *context)
 477 {
 478         free(context);
 479
 480         return ERROR_OK;
 481 }
 482
 483 command_context_t* command_init()
 484 {
 485         command_context_t* context = malloc(sizeof(command_context_t));
 486
 487         context->mode = COMMAND_EXEC;
 488         context->commands = NULL;
 489         context->current_target = 0;
 490         context->echo = 0;
 491         context->output_handler = NULL;
 492         context->output_handler_priv = NULL;
 493
 494         register_command(context, NULL, "help", command_print_help,
 495                                          COMMAND_EXEC, "display this help");
 496
 497         register_command(context, NULL, "sleep", handle_sleep_command,
 498                                          COMMAND_ANY, "sleep for <n> milliseconds");
 499
 500         return context;
 501 }
 502
 503 /* sleep command sleeps for <n> miliseconds
 504  * this is useful in target startup scripts
 505  */
 506 int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 507 {
 508         unsigned long duration = 0;
 509
 510         if (argc == 1)
 511         {
 512                 duration = strtoul(args[0], NULL, 0);
 513                 usleep(duration * 1000);
 514         }
 515
 516         return ERROR_OK;
 517 }