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 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include "replacements.h"
  28
  29 #include "command.h"
  30
  31 #include "log.h"
  32
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <ctype.h>
  36 #include <stdarg.h>
  37 #include <stdio.h>
  38 #include <unistd.h>
  39
  40 int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  41
  42 int build_unique_lengths(command_context_t *context, command_t *commands)
  43 {
  44         command_t *c, *p;
  45
  46         /* iterate through all commands */
  47         for (c = commands; c; c = c->next)
  48         {
  49                 /* find out how many characters are required to uniquely identify a command */
  50                 for (c->unique_len = 1; c->unique_len <= strlen(c->name); c->unique_len++)
  51                 {
  52                         int foundmatch = 0;
  53
  54                         /* for every command, see if the current length is enough */
  55                         for (p = commands; p; p = p->next)
  56                         {
  57                                 /* ignore the command itself */
  58                                 if (c == p)
  59                                         continue;
  60
  61                                 /* compare commands up to the current length */
  62                                 if (strncmp(p->name, c->name, c->unique_len) == 0)
  63                                         foundmatch++;
  64                         }
  65
  66                         /* when none of the commands matched, we've found the minimum length required */
  67                         if (!foundmatch)
  68                                 break;
  69                 }
  70
  71                 /* if the current command has children, build the unique lengths for them */
  72                 if (c->children)
  73                         build_unique_lengths(context, c->children);
  74         }
  75
  76         return ERROR_OK;
  77 }
  78
  79 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)
  80 {
  81         command_t *c, *p;
  82
  83         if (!context || !name)
  84                 return NULL;
  85
  86         c = malloc(sizeof(command_t));
  87
  88         c->name = strdup(name);
  89         c->parent = parent;
  90         c->children = NULL;
  91         c->handler = handler;
  92         c->mode = mode;
  93         if (help)
  94                 c->help = strdup(help);
  95         else
  96                 c->help = NULL;
  97         c->unique_len = 0;
  98         c->next = NULL;
  99
 100         /* place command in tree */
 101         if (parent)
 102         {
 103                 if (parent->children)
 104                 {
 105                         /* find last child */
 106                         for (p = parent->children; p && p->next; p = p->next);
 107                         if (p)
 108                                 p->next = c;
 109                 }
 110                 else
 111                 {
 112                         parent->children = c;
 113                 }
 114         }
 115         else
 116         {
 117                 if (context->commands)
 118                 {
 119                         /* find last command */
 120                         for (p = context->commands; p && p->next; p = p->next);
 121                         if (p)
 122                                 p->next = c;
 123                 }
 124                 else
 125                 {
 126                         context->commands = c;
 127                 }
 128         }
 129
 130         /* update unique lengths */
 131         build_unique_lengths(context, (parent) ? parent : context->commands);
 132
 133         return c;
 134 }
 135
 136 int unregister_command(command_context_t *context, char *name)
 137 {
 138         command_t *c, *p = NULL, *c2;
 139
 140         if ((!context) || (!name))
 141                 return ERROR_INVALID_ARGUMENTS;
 142
 143         /* find command */
 144         for (c = context->commands; c; c = c->next)
 145         {
 146                 if (strcmp(name, c->name) == 0)
 147                 {
 148                         /* unlink command */
 149                         if (p)
 150                         {
 151                                 p->next = c->next;
 152                         }
 153                         else
 154                         {
 155                                 context->commands = c->next;
 156                         }
 157
 158                         /* unregister children */
 159                         if (c->children)
 160                         {
 161                                 for (c2 = c->children; c2; c2 = c2->next)
 162                                 {
 163                                         free(c2->name);
 164                                         if (c2->help)
 165                                                 free(c2->help);
 166                                         free(c2);
 167                                 }
 168                         }
 169
 170                         /* delete command */
 171                         free(c->name);
 172                         if (c->help)
 173                                 free(c->help);
 174                         free(c);
 175                 }
 176
 177                 /* remember the last command for unlinking */
 178                 p = c;
 179         }
 180
 181         return ERROR_OK;
 182 }
 183
 184 int parse_line(char *line, char *words[], int max_words)
 185 {
 186         int nwords = 0;
 187         char *p = line;
 188         char *word_start = line;
 189         int inquote = 0;
 190
 191         while (nwords < max_words - 1)
 192         {
 193                 /* check if we reached
 194                  * a terminating NUL
 195                  * a matching closing quote character " or '
 196                  * we're inside a word but not a quote, and the current character is whitespace
 197                  */
 198                 if (!*p || *p == inquote || (word_start && !inquote && isspace(*p)))
 199                 {
 200                         /* we're inside a word or quote, and reached its end*/
 201                         if (word_start)
 202                         {
 203                          int len;
 204                             char *word_end=p;
 205                             /* This will handle extra whitespace within quotes */
 206                          while (isspace(*word_start)&&(word_start<word_end))
 207                                    word_start++;
 208                          while (isspace(*(word_end-1))&&(word_start<word_end))
 209                                    word_end--;
 210
 211                             len = word_end - word_start;
 212
 213                             if (len>0)
 214                             {
 215                                    /* copy the word */
 216                                    memcpy(words[nwords] = malloc(len + 1), word_start, len);
 217                                    /* add terminating NUL */
 218                                    words[nwords++][len] = 0;
 219                             }
 220                         }
 221
 222                         /* we're done parsing the line */
 223                         if (!*p)
 224                                 break;
 225
 226                         /* skip over trailing quote or whitespace*/
 227                         if (inquote || isspace(*p))
 228                                 p++;
 229                      while (isspace(*p))
 230                             p++;
 231
 232                         inquote = 0;
 233                         word_start = 0;
 234                 }
 235                 else if (*p == '"' || *p == '\'')
 236                 {
 237                         /* we've reached the beginning of a quote */
 238                         inquote = *p++;
 239                         word_start = p;
 240                 }
 241                 else
 242                 {
 243                         /* we've reached the beginning of a new word */
 244                         if (!word_start)
 245                                 word_start = p;
 246
 247                         /* normal character, skip */
 248                         p++;
 249                 }
 250         }
 251
 252         return nwords;
 253 }
 254
 255 void command_print(command_context_t *context, char *format, ...)
 256 {
 257         va_list ap;
 258         char *buffer = NULL;
 259         int n, size = 0;
 260         char *p;
 261
 262         va_start(ap, format);
 263
 264         /* process format string */
 265         /* TODO: possible bug. va_list is undefined after the first call to vsnprintf */
 266         while (!buffer || (n = vsnprintf(buffer, size, format, ap)) >= size)
 267         {
 268                 /* increase buffer until it fits the whole string */
 269                 if (!(p = realloc(buffer, size += 4096)))
 270                         return;
 271
 272                 buffer = p;
 273         }
 274
 275         /* vsnprintf failed */
 276         if (n < 0)
 277                 return;
 278
 279         p = buffer;
 280
 281         /* process lines in buffer */
 282         do {
 283                 char *next = strchr(p, '\n');
 284
 285                 if (next)
 286                         *next++ = 0;
 287
 288                 if (context->output_handler)
 289                         context->output_handler(context, p);
 290
 291                 p = next;
 292         } while (p);
 293
 294         if (buffer)
 295                 free(buffer);
 296
 297         va_end(ap);
 298 }
 299
 300 int find_and_run_command(command_context_t *context, command_t *commands, char *words[], int num_words, int start_word)
 301 {
 302         command_t *c;
 303
 304         for (c = commands; c; c = c->next)
 305         {
 306                 if (strncasecmp(c->name, words[start_word], c->unique_len))
 307                         continue;
 308
 309                 if (strncasecmp(c->name, words[start_word], strlen(words[start_word])))
 310                         continue;
 311
 312                 if ((c->mode == context->mode) || (c->mode == COMMAND_ANY))
 313                 {
 314                         if (!c->children)
 315                         {
 316                                 if (!c->handler)
 317                                 {
 318                                         command_print(context, "No handler for command");
 319                                         break;
 320                                 }
 321                                 else
 322                                 {
 323                                         return c->handler(context, c->name, words + start_word + 1, num_words - start_word - 1);
 324                                 }
 325                         }
 326                         else
 327                         {
 328                                 if (start_word == num_words - 1)
 329                                 {
 330                                         command_print(context, "Incomplete command");
 331                                         break;
 332                                 }
 333                                 return find_and_run_command(context, c->children, words, num_words, start_word + 1);
 334                         }
 335                 }
 336         }
 337
 338         command_print(context, "Command %s not found", words[start_word]);
 339         return ERROR_OK;
 340 }
 341
 342 int command_run_line(command_context_t *context, char *line)
 343 {
 344         int nwords;
 345         char *words[128] = {0};
 346         int retval;
 347         int i;
 348
 349         if ((!context) || (!line))
 350                 return ERROR_INVALID_ARGUMENTS;
 351
 352         /* skip preceding whitespace */
 353         while (isspace(*line))
 354                 line++;
 355
 356         /* empty line, ignore */
 357         if (!*line)
 358                 return ERROR_OK;
 359
 360         if (context->echo)
 361         {
 362                 command_print(context, "%s", line);
 363         }
 364
 365         nwords = parse_line(line, words, sizeof(words) / sizeof(words[0]));
 366
 367         if (nwords > 0)
 368                 retval = find_and_run_command(context, context->commands, words, nwords, 0);
 369         else
 370                 return ERROR_INVALID_ARGUMENTS;
 371
 372         for (i = 0; i < nwords; i++)
 373                 free(words[i]);
 374
 375         return retval;
 376 }
 377
 378 int command_run_file(command_context_t *context, FILE *file, enum command_mode mode)
 379 {
 380         int retval;
 381         int old_command_mode;
 382         char buffer[4096];
 383
 384         old_command_mode = context->mode;
 385         context->mode = mode;
 386
 387         while (fgets(buffer, 4096, file))
 388         {
 389                 char *p;
 390                 char *cmd, *end;
 391
 392                 /* stop processing line after a comment (#, !) or a LF, CR were encountered */
 393                 if ((p = strpbrk(buffer, "#!\r\n")))
 394                         *p = 0;
 395
 396                 /* skip over leading whitespace */
 397                 cmd = buffer;
 398                 while (isspace(*cmd))
 399                         cmd++;
 400
 401                 /* empty (all whitespace) line? */
 402                 if (!*cmd)
 403                         continue;
 404
 405                 /* search the end of the current line, ignore trailing whitespace */
 406                 for (p = end = cmd; *p; p++)
 407                         if (!isspace(*p))
 408                                 end = p;
 409
 410                 /* terminate end */
 411                 *++end = 0;
 412                 if (strcasecmp(cmd, "quit") == 0)
 413                         break;
 414
 415                 /* run line */
 416                 if ((retval = command_run_line(context, cmd)) == ERROR_COMMAND_CLOSE_CONNECTION)
 417                         break;
 418         }
 419
 420         context->mode = old_command_mode;
 421
 422         return retval;
 423 }
 424
 425 void command_print_help_line(command_context_t* context, struct command_s *command, int indent)
 426 {
 427         command_t *c;
 428         char indents[32] = {0};
 429         char *help = "no help available";
 430         char name_buf[64];
 431         int i;
 432
 433         for (i = 0; i < indent; i+=2)
 434         {
 435                 indents[i*2] = ' ';
 436                 indents[i*2+1] = '-';
 437         }
 438         indents[i*2] = 0;
 439
 440         if ((command->mode == COMMAND_EXEC) || (command->mode == COMMAND_ANY))
 441         {
 442                 if (command->help)
 443                         help = command->help;
 444
 445                 snprintf(name_buf, 64, command->name);
 446                 strncat(name_buf, indents, 64);
 447                 command_print(context, "%20s\t%s", name_buf, help);
 448         }
 449
 450         if (command->children)
 451         {
 452                 for (c = command->children; c; c = c->next)
 453                 {
 454                         command_print_help_line(context, c, indent + 1);
 455                 }
 456         }
 457 }
 458
 459 int command_print_help(command_context_t* context, char* name, char** args, int argc)
 460 {
 461         command_t *c;
 462
 463         for (c = context->commands; c; c = c->next)
 464         {
 465                 if (argc == 1)
 466                 {
 467                          if (strncasecmp(c->name, args[0], c->unique_len))
 468                                  continue;
 469
 470                          if (strncasecmp(c->name, args[0], strlen(args[0])))
 471                                  continue;
 472                 }
 473
 474                 command_print_help_line(context, c, 0);
 475         }
 476
 477         return ERROR_OK;
 478 }
 479
 480 void command_set_output_handler(command_context_t* context, int (*output_handler)(struct command_context_s *context, char* line), void *priv)
 481 {
 482         context->output_handler = output_handler;
 483         context->output_handler_priv = priv;
 484 }
 485
 486 command_context_t* copy_command_context(command_context_t* context)
 487 {
 488         command_context_t* copy_context = malloc(sizeof(command_context_t));
 489
 490         *copy_context = *context;
 491
 492         return copy_context;
 493 }
 494
 495 int command_done(command_context_t *context)
 496 {
 497         free(context);
 498
 499         return ERROR_OK;
 500 }
 501
 502 command_context_t* command_init()
 503 {
 504         command_context_t* context = malloc(sizeof(command_context_t));
 505
 506         context->mode = COMMAND_EXEC;
 507         context->commands = NULL;
 508         context->current_target = 0;
 509         context->echo = 0;
 510         context->output_handler = NULL;
 511         context->output_handler_priv = NULL;
 512
 513         register_command(context, NULL, "help", command_print_help,
 514                                          COMMAND_EXEC, "display this help");
 515
 516         register_command(context, NULL, "sleep", handle_sleep_command,
 517                                          COMMAND_ANY, "sleep for <n> milliseconds");
 518
 519         return context;
 520 }
 521
 522 /* sleep command sleeps for <n> miliseconds
 523  * this is useful in target startup scripts
 524  */
 525 int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 526 {
 527         unsigned long duration = 0;
 528
 529         if (argc == 1)
 530         {
 531                 duration = strtoul(args[0], NULL, 0);
 532                 usleep(duration * 1000);
 533         }
 534
 535         return ERROR_OK;
 536 }