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 #include "time_support.h"
  33
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <ctype.h>
  37 #include <stdarg.h>
  38 #include <stdio.h>
  39 #include <unistd.h>
  40
  41 void command_print_help_line(command_context_t* context, struct command_s *command, int indent);
  42
  43 int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  44 int handle_time_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  45
  46 int build_unique_lengths(command_context_t *context, command_t *commands)
  47 {
  48         command_t *c, *p;
  49
  50         /* iterate through all commands */
  51         for (c = commands; c; c = c->next)
  52         {
  53                 /* find out how many characters are required to uniquely identify a command */
  54                 for (c->unique_len = 1; c->unique_len <= strlen(c->name); c->unique_len++)
  55                 {
  56                         int foundmatch = 0;
  57
  58                         /* for every command, see if the current length is enough */
  59                         for (p = commands; p; p = p->next)
  60                         {
  61                                 /* ignore the command itself */
  62                                 if (c == p)
  63                                         continue;
  64
  65                                 /* compare commands up to the current length */
  66                                 if (strncmp(p->name, c->name, c->unique_len) == 0)
  67                                         foundmatch++;
  68                         }
  69
  70                         /* when none of the commands matched, we've found the minimum length required */
  71                         if (!foundmatch)
  72                                 break;
  73                 }
  74
  75                 /* if the current command has children, build the unique lengths for them */
  76                 if (c->children)
  77                         build_unique_lengths(context, c->children);
  78         }
  79
  80         return ERROR_OK;
  81 }
  82
  83 /* Avoid evaluating this each time we add a command. Reduces overhead from O(n^2) to O(n).
  84  * Makes a difference on ARM7 types machines and is not observable on GHz machines.
  85  */
  86 static int unique_length_dirty = 1;
  87
  88 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)
  89 {
  90         command_t *c, *p;
  91         unique_length_dirty = 1;
  92
  93         if (!context || !name)
  94                 return NULL;
  95
  96         c = malloc(sizeof(command_t));
  97
  98         c->name = strdup(name);
  99         c->parent = parent;
 100         c->children = NULL;
 101         c->handler = handler;
 102         c->mode = mode;
 103         if (help)
 104                 c->help = strdup(help);
 105         else
 106                 c->help = NULL;
 107         c->unique_len = 0;
 108         c->next = NULL;
 109
 110         /* place command in tree */
 111         if (parent)
 112         {
 113                 if (parent->children)
 114                 {
 115                         /* find last child */
 116                         for (p = parent->children; p && p->next; p = p->next);
 117                         if (p)
 118                                 p->next = c;
 119                 }
 120                 else
 121                 {
 122                         parent->children = c;
 123                 }
 124         }
 125         else
 126         {
 127                 if (context->commands)
 128                 {
 129                         /* find last command */
 130                         for (p = context->commands; p && p->next; p = p->next);
 131                         if (p)
 132                                 p->next = c;
 133                 }
 134                 else
 135                 {
 136                         context->commands = c;
 137                 }
 138         }
 139
 140         return c;
 141 }
 142
 143 int unregister_command(command_context_t *context, char *name)
 144 {
 145         unique_length_dirty = 1;
 146
 147         command_t *c, *p = NULL, *c2;
 148
 149         if ((!context) || (!name))
 150                 return ERROR_INVALID_ARGUMENTS;
 151
 152         /* find command */
 153         for (c = context->commands; c; c = c->next)
 154         {
 155                 if (strcmp(name, c->name) == 0)
 156                 {
 157                         /* unlink command */
 158                         if (p)
 159                         {
 160                                 p->next = c->next;
 161                         }
 162                         else
 163                         {
 164                                 context->commands = c->next;
 165                         }
 166
 167                         /* unregister children */
 168                         if (c->children)
 169                         {
 170                                 for (c2 = c->children; c2; c2 = c2->next)
 171                                 {
 172                                         free(c2->name);
 173                                         if (c2->help)
 174                                                 free(c2->help);
 175                                         free(c2);
 176                                 }
 177                         }
 178
 179                         /* delete command */
 180                         free(c->name);
 181                         if (c->help)
 182                                 free(c->help);
 183                         free(c);
 184                 }
 185
 186                 /* remember the last command for unlinking */
 187                 p = c;
 188         }
 189
 190         return ERROR_OK;
 191 }
 192
 193 int parse_line(char *line, char *words[], int max_words)
 194 {
 195         int nwords = 0;
 196         char *p = line;
 197         char *word_start = line;
 198         int inquote = 0;
 199
 200         while (nwords < max_words - 1)
 201         {
 202                 /* check if we reached
 203                  * a terminating NUL
 204                  * a matching closing quote character " or '
 205                  * we're inside a word but not a quote, and the current character is whitespace
 206                  */
 207                 if (!*p || *p == inquote || (word_start && !inquote && isspace(*p)))
 208                 {
 209                         /* we're inside a word or quote, and reached its end*/
 210                         if (word_start)
 211                         {
 212                                 int len;
 213                                 char *word_end=p;
 214
 215                                 /* This will handle extra whitespace within quotes */
 216                                 while (isspace(*word_start)&&(word_start<word_end))
 217                                         word_start++;
 218                                 while (isspace(*(word_end-1))&&(word_start<word_end))
 219                                         word_end--;
 220                                 len = word_end - word_start;
 221
 222                                 if (len>0)
 223                                 {
 224                                         /* copy the word */
 225                                         memcpy(words[nwords] = malloc(len + 1), word_start, len);
 226                                         /* add terminating NUL */
 227                                         words[nwords++][len] = 0;
 228                                 }
 229                         }
 230                         /* we're done parsing the line */
 231                         if (!*p)
 232                                 break;
 233
 234                         /* skip over trailing quote or whitespace*/
 235                         if (inquote || isspace(*p))
 236                                 p++;
 237                         while (isspace(*p))
 238                                 p++;
 239
 240                         inquote = 0;
 241                         word_start = 0;
 242                 }
 243                 else if (*p == '"' || *p == '\'')
 244                 {
 245                         /* we've reached the beginning of a quote */
 246                         inquote = *p++;
 247                         word_start = p;
 248                 }
 249                 else
 250                 {
 251                         /* we've reached the beginning of a new word */
 252                         if (!word_start)
 253                                 word_start = p;
 254
 255                         /* normal character, skip */
 256                         p++;
 257                 }
 258         }
 259
 260         return nwords;
 261 }
 262
 263 void command_print(command_context_t *context, char *format, ...)
 264 {
 265         char *buffer = NULL;
 266         int n, size = 0;
 267         char *p;
 268
 269         /* process format string */
 270         for (;;)
 271         {
 272                 va_list ap;
 273                 va_start(ap, format);
 274                 if (!buffer || (n = vsnprintf(buffer, size, format, ap)) >= size)
 275                 {
 276                         /* increase buffer until it fits the whole string */
 277                         if (!(p = realloc(buffer, size += 4096)))
 278                         {
 279                                 /* gotta free up */
 280                                 if (buffer)
 281                                         free(buffer);
 282                                 va_end(ap);
 283                                 return;
 284                         }
 285
 286                         buffer = p;
 287
 288                         va_end(ap);
 289                         continue;
 290                 }
 291                 va_end(ap);
 292                 break;
 293         }
 294
 295         /* vsnprintf failed */
 296         if (n < 0)
 297         {
 298                 if (buffer)
 299                         free(buffer);
 300                 return;
 301         }
 302
 303         p = buffer;
 304
 305         /* process lines in buffer */
 306         do {
 307                 char *next = strchr(p, '\n');
 308
 309                 if (next)
 310                         *next++ = 0;
 311
 312                 if (context->output_handler)
 313                         context->output_handler(context, p);
 314
 315                 p = next;
 316         } while (p);
 317
 318         if (buffer)
 319                 free(buffer);
 320 }
 321
 322 int find_and_run_command(command_context_t *context, command_t *commands, char *words[], int num_words, int start_word)
 323 {
 324         command_t *c;
 325
 326         if (unique_length_dirty)
 327         {
 328                 unique_length_dirty = 0;
 329                 /* update unique lengths */
 330                 build_unique_lengths(context, context->commands);
 331         }
 332
 333         for (c = commands; c; c = c->next)
 334         {
 335                 if (strncasecmp(c->name, words[start_word], c->unique_len))
 336                         continue;
 337
 338                 if (strncasecmp(c->name, words[start_word], strlen(words[start_word])))
 339                         continue;
 340
 341                 if ((context->mode == COMMAND_CONFIG) || (c->mode == COMMAND_ANY) || (c->mode == context->mode) )
 342                 {
 343                         if (!c->children)
 344                         {
 345                                 if (!c->handler)
 346                                 {
 347                                         command_print(context, "No handler for command");
 348                                         break;
 349                                 }
 350                                 else
 351                                 {
 352                                         int retval = c->handler(context, c->name, words + start_word + 1, num_words - start_word - 1);
 353                                         if (retval == ERROR_COMMAND_SYNTAX_ERROR)
 354                                         {
 355                                                 command_print(context, "Syntax error:");
 356                                                 command_print_help_line(context, c, 0);
 357                                         }
 358                                         return retval;
 359                                 }
 360                         }
 361                         else
 362                         {
 363                                 if (start_word == num_words - 1)
 364                                 {
 365                                         command_print(context, "Incomplete command");
 366                                         break;
 367                                 }
 368                                 return find_and_run_command(context, c->children, words, num_words, start_word + 1);
 369                         }
 370                 }
 371         }
 372
 373         command_print(context, "Command %s not found", words[start_word]);
 374         return ERROR_OK;
 375 }
 376
 377 static int command_run_line_inner(command_context_t *context, char *line)
 378 {
 379         int nwords;
 380         char *words[128] = {0};
 381         int retval;
 382         int i;
 383
 384         if ((!context) || (!line))
 385                 return ERROR_INVALID_ARGUMENTS;
 386
 387         /* skip preceding whitespace */
 388         while (isspace(*line))
 389                 line++;
 390
 391         /* empty line, ignore */
 392         if (!*line)
 393                 return ERROR_OK;
 394
 395         /* ignore comments */
 396         if (*line && (line[0] == '#'))
 397                 return ERROR_OK;
 398
 399         if (context->echo)
 400         {
 401                 command_print(context, "%s", line);
 402         }
 403
 404         nwords = parse_line(line, words, sizeof(words) / sizeof(words[0]));
 405
 406         if (nwords > 0)
 407                 retval = find_and_run_command(context, context->commands, words, nwords, 0);
 408         else
 409                 return ERROR_INVALID_ARGUMENTS;
 410
 411         for (i = 0; i < nwords; i++)
 412                 free(words[i]);
 413
 414         return retval;
 415 }
 416
 417 int command_run_line(command_context_t *context, char *line)
 418 {
 419         int retval=command_run_line_inner(context, line);
 420         // we don't want any dangling callbacks!
 421         //
 422         // Capturing output from logging is *very* loosly modeled on C/C++ exceptions.
 423         // the capture must be set up at function entry and
 424         // stops when the function call returns
 425         log_setCallback(NULL, NULL);
 426         return retval;
 427 }
 428 int command_run_file(command_context_t *context, FILE *file, enum command_mode mode)
 429 {
 430         int retval = ERROR_OK;
 431         int old_command_mode;
 432         char *buffer=malloc(4096);
 433         if (buffer==NULL)
 434         {
 435                 return ERROR_INVALID_ARGUMENTS;
 436         }
 437
 438         old_command_mode = context->mode;
 439         context->mode = mode;
 440
 441         while (fgets(buffer, 4096, file))
 442         {
 443                 char *p;
 444                 char *cmd, *end;
 445
 446                 /* stop processing line after a comment (#, !) or a LF, CR were encountered */
 447                 if ((p = strpbrk(buffer, "#!\r\n")))
 448                         *p = 0;
 449
 450                 /* skip over leading whitespace */
 451                 cmd = buffer;
 452                 while (isspace(*cmd))
 453                         cmd++;
 454
 455                 /* empty (all whitespace) line? */
 456                 if (!*cmd)
 457                         continue;
 458
 459                 /* search the end of the current line, ignore trailing whitespace */
 460                 for (p = end = cmd; *p; p++)
 461                         if (!isspace(*p))
 462                                 end = p;
 463
 464                 /* terminate end */
 465                 *++end = 0;
 466                 if (strcasecmp(cmd, "quit") == 0)
 467                         break;
 468
 469                 /* run line */
 470                 if ((retval = command_run_line_inner(context, cmd)) == ERROR_COMMAND_CLOSE_CONNECTION)
 471                         break;
 472         }
 473
 474         context->mode = old_command_mode;
 475
 476
 477         free(buffer);
 478
 479         return retval;
 480 }
 481
 482 void command_print_help_line(command_context_t* context, struct command_s *command, int indent)
 483 {
 484         command_t *c;
 485         char indents[32] = {0};
 486         char *help = "no help available";
 487         char name_buf[64];
 488         int i;
 489
 490         for (i = 0; i < indent; i+=2)
 491         {
 492                 indents[i*2] = ' ';
 493                 indents[i*2+1] = '-';
 494         }
 495         indents[i*2] = 0;
 496
 497         if (command->help)
 498                 help = command->help;
 499
 500         snprintf(name_buf, 64, command->name);
 501         strncat(name_buf, indents, 64);
 502         command_print(context, "%20s\t%s", name_buf, help);
 503
 504         if (command->children)
 505         {
 506                 for (c = command->children; c; c = c->next)
 507                 {
 508                         command_print_help_line(context, c, indent + 1);
 509                 }
 510         }
 511 }
 512
 513 int command_print_help(command_context_t* context, char* name, char** args, int argc)
 514 {
 515         command_t *c;
 516
 517         for (c = context->commands; c; c = c->next)
 518         {
 519                 if (argc == 1)
 520                 {
 521                          if (strncasecmp(c->name, args[0], c->unique_len))
 522                                  continue;
 523
 524                          if (strncasecmp(c->name, args[0], strlen(args[0])))
 525                                  continue;
 526                 }
 527
 528                 command_print_help_line(context, c, 0);
 529         }
 530
 531         return ERROR_OK;
 532 }
 533
 534 void command_set_output_handler(command_context_t* context, int (*output_handler)(struct command_context_s *context, char* line), void *priv)
 535 {
 536         context->output_handler = output_handler;
 537         context->output_handler_priv = priv;
 538 }
 539
 540 command_context_t* copy_command_context(command_context_t* context)
 541 {
 542         command_context_t* copy_context = malloc(sizeof(command_context_t));
 543
 544         *copy_context = *context;
 545
 546         return copy_context;
 547 }
 548
 549 int command_done(command_context_t *context)
 550 {
 551         free(context);
 552         context = NULL;
 553
 554         return ERROR_OK;
 555 }
 556
 557 command_context_t* command_init()
 558 {
 559         command_context_t* context = malloc(sizeof(command_context_t));
 560
 561         context->mode = COMMAND_EXEC;
 562         context->commands = NULL;
 563         context->current_target = 0;
 564         context->echo = 0;
 565         context->output_handler = NULL;
 566         context->output_handler_priv = NULL;
 567
 568         register_command(context, NULL, "help", command_print_help,
 569                                          COMMAND_EXEC, "display this help");
 570
 571         register_command(context, NULL, "sleep", handle_sleep_command,
 572                                          COMMAND_ANY, "sleep for <n> milliseconds");
 573
 574         register_command(context, NULL, "time", handle_time_command,
 575                                          COMMAND_ANY, "time <cmd + args> - execute <cmd + args> and print time it took");
 576
 577         return context;
 578 }
 579
 580 /* sleep command sleeps for <n> miliseconds
 581  * this is useful in target startup scripts
 582  */
 583 int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 584 {
 585         unsigned long duration = 0;
 586
 587         if (argc == 1)
 588         {
 589                 duration = strtoul(args[0], NULL, 0);
 590                 usleep(duration * 1000);
 591         }
 592
 593         return ERROR_OK;
 594 }
 595
 596 int handle_time_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 597 {
 598         if (argc<1)
 599                 return ERROR_COMMAND_SYNTAX_ERROR;
 600
 601         duration_t duration;
 602         char *duration_text;
 603         int retval;
 604
 605         duration_start_measure(&duration);
 606
 607         retval = find_and_run_command(cmd_ctx, cmd_ctx->commands, args, argc, 0);
 608
 609         duration_stop_measure(&duration, &duration_text);
 610
 611         float t=duration.duration.tv_sec;
 612         t+=((float)duration.duration.tv_usec / 1000000.0);
 613         command_print(cmd_ctx, "%s took %fs", args[0], t);
 614
 615         free(duration_text);
 616
 617         return retval;
 618 }