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 = p - word_start;
 204
 205                                 /* copy the word */
 206                                 memcpy(words[nwords] = malloc(len + 1), word_start, len);
 207                                 /* add terminating NUL */
 208                                 words[nwords++][len] = 0;
 209                         }
 210
 211                         /* we're done parsing the line */
 212                         if (!*p)
 213                                 break;
 214
 215                         /* skip over trailing quote or whitespace*/
 216                         if (inquote || isspace(*p))
 217                                 p++;
 218
 219                         inquote = 0;
 220                         word_start = 0;
 221                 }
 222                 else if (*p == '"' || *p == '\'')
 223                 {
 224                         /* we've reached the beginning of a quote */
 225                         inquote = *p++;
 226                         word_start = p;
 227                 }
 228                 else
 229                 {
 230                         /* we've reached the beginning of a new word */
 231                         if (!word_start)
 232                                 word_start = p;
 233
 234                         /* normal character, skip */
 235                         p++;
 236                 }
 237         }
 238
 239         return nwords;
 240 }
 241
 242 void command_print(command_context_t *context, char *format, ...)
 243 {
 244         va_list ap;
 245         char *buffer = NULL;
 246         int n, size = 0;
 247         char *p;
 248
 249         va_start(ap, format);
 250
 251         /* process format string */
 252         /* TODO: possible bug. va_list is undefined after the first call to vsnprintf */
 253         while (!buffer || (n = vsnprintf(buffer, size, format, ap)) >= size)
 254         {
 255                 /* increase buffer until it fits the whole string */
 256                 if (!(p = realloc(buffer, size += 4096)))
 257                         return;
 258
 259                 buffer = p;
 260         }
 261
 262         /* vsnprintf failed */
 263         if (n < 0)
 264                 return;
 265
 266         p = buffer;
 267
 268         /* process lines in buffer */
 269         do {
 270                 char *next = strchr(p, '\n');
 271
 272                 if (next)
 273                         *next++ = 0;
 274
 275                 if (context->output_handler)
 276                         context->output_handler(context, p);
 277
 278                 p = next;
 279         } while (p);
 280
 281         if (buffer)
 282                 free(buffer);
 283
 284         va_end(ap);
 285 }
 286
 287 int find_and_run_command(command_context_t *context, command_t *commands, char *words[], int num_words, int start_word)
 288 {
 289         command_t *c;
 290
 291         for (c = commands; c; c = c->next)
 292         {
 293                 if (strncasecmp(c->name, words[start_word], c->unique_len))
 294                         continue;
 295
 296                 if (strncasecmp(c->name, words[start_word], strlen(words[start_word])))
 297                         continue;
 298
 299                 if ((c->mode == context->mode) || (c->mode == COMMAND_ANY))
 300                 {
 301                         if (!c->children)
 302                         {
 303                                 if (!c->handler)
 304                                 {
 305                                         command_print(context, "No handler for command");
 306                                         break;
 307                                 }
 308                                 else
 309                                 {
 310                                         return c->handler(context, c->name, words + start_word + 1, num_words - start_word - 1);
 311                                 }
 312                         }
 313                         else
 314                         {
 315                                 if (start_word == num_words - 1)
 316                                 {
 317                                         command_print(context, "Incomplete command");
 318                                         break;
 319                                 }
 320                                 return find_and_run_command(context, c->children, words, num_words, start_word + 1);
 321                         }
 322                 }
 323         }
 324
 325         command_print(context, "Command %s not found", words[start_word]);
 326         return ERROR_OK;
 327 }
 328
 329 int command_run_line(command_context_t *context, char *line)
 330 {
 331         int nwords;
 332         char *words[128] = {0};
 333         int retval;
 334         int i;
 335
 336         if ((!context) || (!line))
 337                 return ERROR_INVALID_ARGUMENTS;
 338
 339         /* skip preceding whitespace */
 340         while (isspace(*line))
 341                 line++;
 342
 343         /* empty line, ignore */
 344         if (!*line)
 345                 return ERROR_OK;
 346
 347         if (context->echo)
 348         {
 349                 command_print(context, "%s", line);
 350         }
 351
 352         nwords = parse_line(line, words, sizeof(words) / sizeof(words[0]));
 353
 354         if (nwords > 0)
 355                 retval = find_and_run_command(context, context->commands, words, nwords, 0);
 356         else
 357                 return ERROR_INVALID_ARGUMENTS;
 358
 359         for (i = 0; i < nwords; i++)
 360                 free(words[i]);
 361
 362         return retval;
 363 }
 364
 365 int command_run_file(command_context_t *context, FILE *file, enum command_mode mode)
 366 {
 367         int retval;
 368         int old_command_mode;
 369         char buffer[4096];
 370
 371         old_command_mode = context->mode;
 372         context->mode = mode;
 373
 374         while (fgets(buffer, 4096, file))
 375         {
 376                 char *p;
 377                 char *cmd, *end;
 378
 379                 /* stop processing line after a comment (#, !) or a LF, CR were encountered */
 380                 if ((p = strpbrk(buffer, "#!\r\n")))
 381                         *p = 0;
 382
 383                 /* skip over leading whitespace */
 384                 cmd = buffer;
 385                 while (isspace(*cmd))
 386                         cmd++;
 387
 388                 /* empty (all whitespace) line? */
 389                 if (!*cmd)
 390                         continue;
 391
 392                 /* search the end of the current line, ignore trailing whitespace */
 393                 for (p = end = cmd; *p; p++)
 394                         if (!isspace(*p))
 395                                 end = p;
 396
 397                 /* terminate end */
 398                 *++end = 0;
 399                 if (strcasecmp(cmd, "quit") == 0)
 400                         break;
 401
 402                 /* run line */
 403                 if (command_run_line(context, cmd) == ERROR_COMMAND_CLOSE_CONNECTION)
 404                         break;
 405         }
 406
 407         context->mode = old_command_mode;
 408
 409         return retval;
 410 }
 411
 412 void command_print_help_line(command_context_t* context, struct command_s *command, int indent)
 413 {
 414         command_t *c;
 415         char indents[32] = {0};
 416         char *help = "no help available";
 417         char name_buf[64];
 418         int i;
 419
 420         for (i = 0; i < indent; i+=2)
 421         {
 422                 indents[i*2] = ' ';
 423                 indents[i*2+1] = '-';
 424         }
 425         indents[i*2] = 0;
 426
 427         if ((command->mode == COMMAND_EXEC) || (command->mode == COMMAND_ANY))
 428         {
 429                 if (command->help)
 430                         help = command->help;
 431
 432                 snprintf(name_buf, 64, command->name);
 433                 strncat(name_buf, indents, 64);
 434                 command_print(context, "%20s\t%s", name_buf, help);
 435         }
 436
 437         if (command->children)
 438         {
 439                 for (c = command->children; c; c = c->next)
 440                 {
 441                         command_print_help_line(context, c, indent + 1);
 442                 }
 443         }
 444 }
 445
 446 int command_print_help(command_context_t* context, char* name, char** args, int argc)
 447 {
 448         command_t *c;
 449
 450         for (c = context->commands; c; c = c->next)
 451         {
 452                 if (argc == 1)
 453                 {
 454                          if (strncasecmp(c->name, args[0], c->unique_len))
 455                                  continue;
 456
 457                          if (strncasecmp(c->name, args[0], strlen(args[0])))
 458                                  continue;
 459                 }
 460
 461                 command_print_help_line(context, c, 0);
 462         }
 463
 464         return ERROR_OK;
 465 }
 466
 467 void command_set_output_handler(command_context_t* context, int (*output_handler)(struct command_context_s *context, char* line), void *priv)
 468 {
 469         context->output_handler = output_handler;
 470         context->output_handler_priv = priv;
 471 }
 472
 473 command_context_t* copy_command_context(command_context_t* context)
 474 {
 475         command_context_t* copy_context = malloc(sizeof(command_context_t));
 476
 477         *copy_context = *context;
 478
 479         return copy_context;
 480 }
 481
 482 int command_done(command_context_t *context)
 483 {
 484         free(context);
 485
 486         return ERROR_OK;
 487 }
 488
 489 command_context_t* command_init()
 490 {
 491         command_context_t* context = malloc(sizeof(command_context_t));
 492
 493         context->mode = COMMAND_EXEC;
 494         context->commands = NULL;
 495         context->current_target = 0;
 496         context->echo = 0;
 497         context->output_handler = NULL;
 498         context->output_handler_priv = NULL;
 499
 500         register_command(context, NULL, "help", command_print_help,
 501                                          COMMAND_EXEC, "display this help");
 502
 503         register_command(context, NULL, "sleep", handle_sleep_command,
 504                                          COMMAND_ANY, "sleep for <n> milliseconds");
 505
 506         return context;
 507 }
 508
 509 /* sleep command sleeps for <n> miliseconds
 510  * this is useful in target startup scripts
 511  */
 512 int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 513 {
 514         unsigned long duration = 0;
 515
 516         if (argc == 1)
 517         {
 518                 duration = strtoul(args[0], NULL, 0);
 519                 usleep(duration * 1000);
 520         }
 521
 522         return ERROR_OK;
 523 }