lib/util/util.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Samba utility functions
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Jeremy Allison 2001-2002
   6    Copyright (C) Simo Sorce 2001
   7    Copyright (C) Jim McDonough (jmcd@us.ibm.com)  2003.
   8    Copyright (C) James J Myers 2003
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "system/network.h"
  26 #include "system/filesys.h"
  27 #include "system/locale.h"
  28 #undef malloc
  29 #undef strcasecmp
  30 #undef strncasecmp
  31 #undef strdup
  32 #undef realloc
  33
  34 /**
  35  * @file
  36  * @brief Misc utility functions
  37  */
  38
  39 /**
  40  Find a suitable temporary directory. The result should be copied immediately
  41  as it may be overwritten by a subsequent call.
  42 **/
  43 _PUBLIC_ const char *tmpdir(void)
  44 {
  45         char *p;
  46         if ((p = getenv("TMPDIR")))
  47                 return p;
  48         return "/tmp";
  49 }
  50
  51
  52 /**
  53  Check if a file exists - call vfs_file_exist for samba files.
  54 **/
  55 _PUBLIC_ bool file_exist(const char *fname)
  56 {
  57         struct stat st;
  58
  59         if (stat(fname, &st) != 0) {
  60                 return false;
  61         }
  62
  63         return ((S_ISREG(st.st_mode)) || (S_ISFIFO(st.st_mode)));
  64 }
  65
  66 /**
  67  Check a files mod time.
  68 **/
  69
  70 _PUBLIC_ time_t file_modtime(const char *fname)
  71 {
  72         struct stat st;
  73
  74         if (stat(fname,&st) != 0)
  75                 return(0);
  76
  77         return(st.st_mtime);
  78 }
  79
  80 /**
  81  Check if a directory exists.
  82 **/
  83
  84 _PUBLIC_ bool directory_exist(const char *dname)
  85 {
  86         struct stat st;
  87         bool ret;
  88
  89         if (stat(dname,&st) != 0) {
  90                 return false;
  91         }
  92
  93         ret = S_ISDIR(st.st_mode);
  94         if(!ret)
  95                 errno = ENOTDIR;
  96         return ret;
  97 }
  98
  99 /**
 100  * Try to create the specified directory if it didn't exist.
 101  *
 102  * @retval true if the directory already existed and has the right permissions
 103  * or was successfully created.
 104  */
 105 _PUBLIC_ bool directory_create_or_exist(const char *dname, uid_t uid,
 106                                mode_t dir_perms)
 107 {
 108         mode_t old_umask;
 109         struct stat st;
 110
 111         old_umask = umask(0);
 112         if (lstat(dname, &st) == -1) {
 113                 if (errno == ENOENT) {
 114                         /* Create directory */
 115                         if (mkdir(dname, dir_perms) == -1) {
 116                                 DEBUG(0, ("error creating directory "
 117                                           "%s: %s\n", dname,
 118                                           strerror(errno)));
 119                                 umask(old_umask);
 120                                 return false;
 121                         }
 122                 } else {
 123                         DEBUG(0, ("lstat failed on directory %s: %s\n",
 124                                   dname, strerror(errno)));
 125                         umask(old_umask);
 126                         return false;
 127                 }
 128         } else {
 129                 /* Check ownership and permission on existing directory */
 130                 if (!S_ISDIR(st.st_mode)) {
 131                         DEBUG(0, ("directory %s isn't a directory\n",
 132                                 dname));
 133                         umask(old_umask);
 134                         return false;
 135                 }
 136                 if ((st.st_uid != uid) ||
 137                     ((st.st_mode & 0777) != dir_perms)) {
 138                         DEBUG(0, ("invalid permissions on directory "
 139                                   "%s\n", dname));
 140                         umask(old_umask);
 141                         return false;
 142                 }
 143         }
 144         return true;
 145 }
 146
 147
 148 /**
 149  Set a fd into blocking/nonblocking mode. Uses POSIX O_NONBLOCK if available,
 150  else
 151   if SYSV use O_NDELAY
 152   if BSD use FNDELAY
 153 **/
 154
 155 _PUBLIC_ int set_blocking(int fd, bool set)
 156 {
 157         int val;
 158 #ifdef O_NONBLOCK
 159 #define FLAG_TO_SET O_NONBLOCK
 160 #else
 161 #ifdef SYSV
 162 #define FLAG_TO_SET O_NDELAY
 163 #else /* BSD */
 164 #define FLAG_TO_SET FNDELAY
 165 #endif
 166 #endif
 167
 168         if((val = fcntl(fd, F_GETFL, 0)) == -1)
 169                 return -1;
 170         if(set) /* Turn blocking on - ie. clear nonblock flag */
 171                 val &= ~FLAG_TO_SET;
 172         else
 173                 val |= FLAG_TO_SET;
 174         return fcntl( fd, F_SETFL, val);
 175 #undef FLAG_TO_SET
 176 }
 177
 178
 179 /**
 180  Sleep for a specified number of milliseconds.
 181 **/
 182
 183 _PUBLIC_ void msleep(unsigned int t)
 184 {
 185         struct timeval tval;
 186
 187         tval.tv_sec = t/1000;
 188         tval.tv_usec = 1000*(t%1000);
 189         /* this should be the real select - do NOT replace
 190            with sys_select() */
 191         select(0,NULL,NULL,NULL,&tval);
 192 }
 193
 194 /**
 195  Get my own name, return in malloc'ed storage.
 196 **/
 197
 198 _PUBLIC_ char *get_myname(void)
 199 {
 200         char *hostname;
 201         char *p;
 202
 203         hostname = (char *)malloc(MAXHOSTNAMELEN+1);
 204         *hostname = 0;
 205
 206         /* get my host name */
 207         if (gethostname(hostname, MAXHOSTNAMELEN+1) == -1) {
 208                 DEBUG(0,("gethostname failed\n"));
 209                 return NULL;
 210         }
 211
 212         /* Ensure null termination. */
 213         hostname[MAXHOSTNAMELEN] = '\0';
 214
 215         /* split off any parts after an initial . */
 216         p = strchr(hostname, '.');
 217
 218         if (p != NULL)
 219                 *p = 0;
 220
 221         return hostname;
 222 }
 223
 224 /**
 225  Check if a process exists. Does this work on all unixes?
 226 **/
 227
 228 _PUBLIC_ bool process_exists_by_pid(pid_t pid)
 229 {
 230         /* Doing kill with a non-positive pid causes messages to be
 231          * sent to places we don't want. */
 232         SMB_ASSERT(pid > 0);
 233         return(kill(pid,0) == 0 || errno != ESRCH);
 234 }
 235
 236 /**
 237  Simple routine to do POSIX file locking. Cruft in NFS and 64->32 bit mapping
 238  is dealt with in posix.c
 239 **/
 240
 241 _PUBLIC_ bool fcntl_lock(int fd, int op, off_t offset, off_t count, int type)
 242 {
 243         struct flock lock;
 244         int ret;
 245
 246         DEBUG(8,("fcntl_lock %d %d %.0f %.0f %d\n",fd,op,(double)offset,(double)count,type));
 247
 248         lock.l_type = type;
 249         lock.l_whence = SEEK_SET;
 250         lock.l_start = offset;
 251         lock.l_len = count;
 252         lock.l_pid = 0;
 253
 254         ret = fcntl(fd,op,&lock);
 255
 256         if (ret == -1 && errno != 0)
 257                 DEBUG(3,("fcntl_lock: fcntl lock gave errno %d (%s)\n",errno,strerror(errno)));
 258
 259         /* a lock query */
 260         if (op == F_GETLK) {
 261                 if ((ret != -1) &&
 262                                 (lock.l_type != F_UNLCK) &&
 263                                 (lock.l_pid != 0) &&
 264                                 (lock.l_pid != getpid())) {
 265                         DEBUG(3,("fcntl_lock: fd %d is locked by pid %d\n",fd,(int)lock.l_pid));
 266                         return true;
 267                 }
 268
 269                 /* it must be not locked or locked by me */
 270                 return false;
 271         }
 272
 273         /* a lock set or unset */
 274         if (ret == -1) {
 275                 DEBUG(3,("fcntl_lock: lock failed at offset %.0f count %.0f op %d type %d (%s)\n",
 276                         (double)offset,(double)count,op,type,strerror(errno)));
 277                 return false;
 278         }
 279
 280         /* everything went OK */
 281         DEBUG(8,("fcntl_lock: Lock call successful\n"));
 282
 283         return true;
 284 }
 285
 286 void print_asc(int level, const uint8_t *buf,int len)
 287 {
 288         int i;
 289         for (i=0;i<len;i++)
 290                 DEBUGADD(level,("%c", isprint(buf[i])?buf[i]:'.'));
 291 }
 292
 293 /**
 294  * Write dump of binary data to the log file.
 295  *
 296  * The data is only written if the log level is at least level.
 297  */
 298 static void _dump_data(int level, const uint8_t *buf, int len,
 299                        bool omit_zero_bytes)
 300 {
 301         int i=0;
 302         const uint8_t empty[16];
 303         bool skipped = false;
 304
 305         if (len<=0) return;
 306
 307         if (!DEBUGLVL(level)) return;
 308
 309         memset(&empty, '\0', 16);
 310
 311         for (i=0;i<len;) {
 312
 313                 if (i%16 == 0) {
 314                         if ((omit_zero_bytes == true) &&
 315                             (i > 0) &&
 316                             (len > i+16) &&
 317                             (memcmp(&buf[i], &empty, 16) == 0))
 318                         {
 319                                 i +=16;
 320                                 continue;
 321                         }
 322
 323                         if (i<len)  {
 324                                 DEBUGADD(level,("[%04X] ",i));
 325                         }
 326                 }
 327
 328                 DEBUGADD(level,("%02X ",(int)buf[i]));
 329                 i++;
 330                 if (i%8 == 0) DEBUGADD(level,("  "));
 331                 if (i%16 == 0) {
 332
 333                         print_asc(level,&buf[i-16],8); DEBUGADD(level,(" "));
 334                         print_asc(level,&buf[i-8],8); DEBUGADD(level,("\n"));
 335
 336                         if ((omit_zero_bytes == true) &&
 337                             (len > i+16) &&
 338                             (memcmp(&buf[i], &empty, 16) == 0)) {
 339                                 if (!skipped) {
 340                                         DEBUGADD(level,("skipping zero buffer bytes\n"));
 341                                         skipped = true;
 342                                 }
 343                         }
 344                 }
 345         }
 346
 347         if (i%16) {
 348                 int n;
 349                 n = 16 - (i%16);
 350                 DEBUGADD(level,(" "));
 351                 if (n>8) DEBUGADD(level,(" "));
 352                 while (n--) DEBUGADD(level,("   "));
 353                 n = MIN(8,i%16);
 354                 print_asc(level,&buf[i-(i%16)],n); DEBUGADD(level,( " " ));
 355                 n = (i%16) - n;
 356                 if (n>0) print_asc(level,&buf[i-n],n);
 357                 DEBUGADD(level,("\n"));
 358         }
 359
 360 }
 361
 362 /**
 363  * Write dump of binary data to the log file.
 364  *
 365  * The data is only written if the log level is at least level.
 366  */
 367 _PUBLIC_ void dump_data(int level, const uint8_t *buf, int len)
 368 {
 369         _dump_data(level, buf, len, false);
 370 }
 371
 372 /**
 373  * Write dump of binary data to the log file.
 374  *
 375  * The data is only written if the log level is at least level.
 376  * 16 zero bytes in a row are ommited
 377  */
 378 _PUBLIC_ void dump_data_skip_zeros(int level, const uint8_t *buf, int len)
 379 {
 380         _dump_data(level, buf, len, true);
 381 }
 382
 383
 384 /**
 385  malloc that aborts with smb_panic on fail or zero size.
 386 **/
 387
 388 _PUBLIC_ void *smb_xmalloc(size_t size)
 389 {
 390         void *p;
 391         if (size == 0)
 392                 smb_panic("smb_xmalloc: called with zero size.\n");
 393         if ((p = malloc(size)) == NULL)
 394                 smb_panic("smb_xmalloc: malloc fail.\n");
 395         return p;
 396 }
 397
 398 /**
 399  Memdup with smb_panic on fail.
 400 **/
 401
 402 _PUBLIC_ void *smb_xmemdup(const void *p, size_t size)
 403 {
 404         void *p2;
 405         p2 = smb_xmalloc(size);
 406         memcpy(p2, p, size);
 407         return p2;
 408 }
 409
 410 /**
 411  strdup that aborts on malloc fail.
 412 **/
 413
 414 char *smb_xstrdup(const char *s)
 415 {
 416 #if defined(PARANOID_MALLOC_CHECKER)
 417 #ifdef strdup
 418 #undef strdup
 419 #endif
 420 #endif
 421
 422 #ifndef HAVE_STRDUP
 423 #define strdup rep_strdup
 424 #endif
 425
 426         char *s1 = strdup(s);
 427 #if defined(PARANOID_MALLOC_CHECKER)
 428 #ifdef strdup
 429 #undef strdup
 430 #endif
 431 #define strdup(s) __ERROR_DONT_USE_STRDUP_DIRECTLY
 432 #endif
 433         if (!s1) {
 434                 smb_panic("smb_xstrdup: malloc failed");
 435         }
 436         return s1;
 437
 438 }
 439
 440 /**
 441  strndup that aborts on malloc fail.
 442 **/
 443
 444 char *smb_xstrndup(const char *s, size_t n)
 445 {
 446 #if defined(PARANOID_MALLOC_CHECKER)
 447 #ifdef strndup
 448 #undef strndup
 449 #endif
 450 #endif
 451
 452 #if (defined(BROKEN_STRNDUP) || !defined(HAVE_STRNDUP))
 453 #undef HAVE_STRNDUP
 454 #define strndup rep_strndup
 455 #endif
 456
 457         char *s1 = strndup(s, n);
 458 #if defined(PARANOID_MALLOC_CHECKER)
 459 #ifdef strndup
 460 #undef strndup
 461 #endif
 462 #define strndup(s,n) __ERROR_DONT_USE_STRNDUP_DIRECTLY
 463 #endif
 464         if (!s1) {
 465                 smb_panic("smb_xstrndup: malloc failed");
 466         }
 467         return s1;
 468 }
 469
 470
 471
 472 /**
 473  Like strdup but for memory.
 474 **/
 475
 476 _PUBLIC_ void *memdup(const void *p, size_t size)
 477 {
 478         void *p2;
 479         if (size == 0)
 480                 return NULL;
 481         p2 = malloc(size);
 482         if (!p2)
 483                 return NULL;
 484         memcpy(p2, p, size);
 485         return p2;
 486 }
 487
 488 /**
 489  * Write a password to the log file.
 490  *
 491  * @note Only actually does something if DEBUG_PASSWORD was defined during
 492  * compile-time.
 493  */
 494 _PUBLIC_ void dump_data_pw(const char *msg, const uint8_t * data, size_t len)
 495 {
 496 #ifdef DEBUG_PASSWORD
 497         DEBUG(11, ("%s", msg));
 498         if (data != NULL && len > 0)
 499         {
 500                 dump_data(11, data, len);
 501         }
 502 #endif
 503 }
 504
 505
 506 /**
 507  * see if a range of memory is all zero. A NULL pointer is considered
 508  * to be all zero
 509  */
 510 _PUBLIC_ bool all_zero(const uint8_t *ptr, size_t size)
 511 {
 512         int i;
 513         if (!ptr) return true;
 514         for (i=0;i<size;i++) {
 515                 if (ptr[i]) return false;
 516         }
 517         return true;
 518 }
 519
 520 /**
 521   realloc an array, checking for integer overflow in the array size
 522 */
 523 _PUBLIC_ void *realloc_array(void *ptr, size_t el_size, unsigned count, bool free_on_fail)
 524 {
 525 #define MAX_MALLOC_SIZE 0x7fffffff
 526         if (count == 0 ||
 527             count >= MAX_MALLOC_SIZE/el_size) {
 528                 if (free_on_fail)
 529                         SAFE_FREE(ptr);
 530                 return NULL;
 531         }
 532         if (!ptr) {
 533                 return malloc(el_size * count);
 534         }
 535         return realloc(ptr, el_size * count);
 536 }
 537
 538 /****************************************************************************
 539  Type-safe malloc.
 540 ****************************************************************************/
 541
 542 void *malloc_array(size_t el_size, unsigned int count)
 543 {
 544         return realloc_array(NULL, el_size, count, false);
 545 }
 546
 547 _PUBLIC_ void *talloc_check_name_abort(const void *ptr, const char *name)
 548 {
 549         void *result;
 550
 551         result = talloc_check_name(ptr, name);
 552         if (result != NULL)
 553                 return result;
 554
 555         DEBUG(0, ("Talloc type mismatch, expected %s, got %s\n",
 556                   name, talloc_get_name(ptr)));
 557         smb_panic("talloc type mismatch");
 558         /* Keep the compiler happy */
 559         return NULL;
 560 }
 561
 562 /**
 563  Trim the specified elements off the front and back of a string.
 564 **/
 565 _PUBLIC_ bool trim_string(char *s, const char *front, const char *back)
 566 {
 567         bool ret = false;
 568         size_t front_len;
 569         size_t back_len;
 570         size_t len;
 571
 572         /* Ignore null or empty strings. */
 573         if (!s || (s[0] == '\0'))
 574                 return false;
 575
 576         front_len       = front? strlen(front) : 0;
 577         back_len        = back? strlen(back) : 0;
 578
 579         len = strlen(s);
 580
 581         if (front_len) {
 582                 while (len && strncmp(s, front, front_len)==0) {
 583                         /* Must use memmove here as src & dest can
 584                          * easily overlap. Found by valgrind. JRA. */
 585                         memmove(s, s+front_len, (len-front_len)+1);
 586                         len -= front_len;
 587                         ret=true;
 588                 }
 589         }
 590
 591         if (back_len) {
 592                 while ((len >= back_len) && strncmp(s+len-back_len,back,back_len)==0) {
 593                         s[len-back_len]='\0';
 594                         len -= back_len;
 595                         ret=true;
 596                 }
 597         }
 598         return ret;
 599 }
 600
 601 /**
 602  Find the number of 'c' chars in a string
 603 **/
 604 _PUBLIC_ _PURE_ size_t count_chars(const char *s, char c)
 605 {
 606         size_t count = 0;
 607
 608         while (*s) {
 609                 if (*s == c) count++;
 610                 s ++;
 611         }
 612
 613         return count;
 614 }
 615
 616 /**
 617  Routine to get hex characters and turn them into a 16 byte array.
 618  the array can be variable length, and any non-hex-numeric
 619  characters are skipped.  "0xnn" or "0Xnn" is specially catered
 620  for.
 621
 622  valid examples: "0A5D15"; "0x15, 0x49, 0xa2"; "59\ta9\te3\n"
 623
 624
 625 **/
 626 _PUBLIC_ size_t strhex_to_str(char *p, size_t p_len, const char *strhex, size_t strhex_len)
 627 {
 628         size_t i;
 629         size_t num_chars = 0;
 630         uint8_t   lonybble, hinybble;
 631         const char     *hexchars = "0123456789ABCDEF";
 632         char           *p1 = NULL, *p2 = NULL;
 633
 634         for (i = 0; i < strhex_len && strhex[i] != 0; i++) {
 635                 if (strncasecmp(hexchars, "0x", 2) == 0) {
 636                         i++; /* skip two chars */
 637                         continue;
 638                 }
 639
 640                 if (!(p1 = strchr(hexchars, toupper((unsigned char)strhex[i]))))
 641                         break;
 642
 643                 i++; /* next hex digit */
 644
 645                 if (!(p2 = strchr(hexchars, toupper((unsigned char)strhex[i]))))
 646                         break;
 647
 648                 /* get the two nybbles */
 649                 hinybble = PTR_DIFF(p1, hexchars);
 650                 lonybble = PTR_DIFF(p2, hexchars);
 651
 652                 if (num_chars >= p_len) {
 653                         break;
 654                 }
 655
 656                 p[num_chars] = (hinybble << 4) | lonybble;
 657                 num_chars++;
 658
 659                 p1 = NULL;
 660                 p2 = NULL;
 661         }
 662         return num_chars;
 663 }
 664
 665 /**
 666  * Parse a hex string and return a data blob.
 667  */
 668 _PUBLIC_ _PURE_ DATA_BLOB strhex_to_data_blob(TALLOC_CTX *mem_ctx, const char *strhex)
 669 {
 670         DATA_BLOB ret_blob = data_blob_talloc(mem_ctx, NULL, strlen(strhex)/2+1);
 671
 672         ret_blob.length = strhex_to_str((char *)ret_blob.data, ret_blob.length,
 673                                         strhex,
 674                                         strlen(strhex));
 675
 676         return ret_blob;
 677 }
 678
 679
 680 /**
 681  * Routine to print a buffer as HEX digits, into an allocated string.
 682  */
 683 _PUBLIC_ void hex_encode(const unsigned char *buff_in, size_t len, char **out_hex_buffer)
 684 {
 685         int i;
 686         char *hex_buffer;
 687
 688         *out_hex_buffer = malloc_array_p(char, (len*2)+1);
 689         hex_buffer = *out_hex_buffer;
 690
 691         for (i = 0; i < len; i++)
 692                 slprintf(&hex_buffer[i*2], 3, "%02X", buff_in[i]);
 693 }
 694
 695 /**
 696  * talloc version of hex_encode()
 697  */
 698 _PUBLIC_ char *hex_encode_talloc(TALLOC_CTX *mem_ctx, const unsigned char *buff_in, size_t len)
 699 {
 700         int i;
 701         char *hex_buffer;
 702
 703         hex_buffer = talloc_array(mem_ctx, char, (len*2)+1);
 704         if (!hex_buffer) {
 705                 return NULL;
 706         }
 707
 708         for (i = 0; i < len; i++)
 709                 slprintf(&hex_buffer[i*2], 3, "%02X", buff_in[i]);
 710
 711         talloc_set_name_const(hex_buffer, hex_buffer);
 712         return hex_buffer;
 713 }
 714
 715 /**
 716  Unescape a URL encoded string, in place.
 717 **/
 718
 719 _PUBLIC_ void rfc1738_unescape(char *buf)
 720 {
 721         char *p=buf;
 722
 723         while ((p=strchr(p,'+')))
 724                 *p = ' ';
 725
 726         p = buf;
 727
 728         while (p && *p && (p=strchr(p,'%'))) {
 729                 int c1 = p[1];
 730                 int c2 = p[2];
 731
 732                 if (c1 >= '0' && c1 <= '9')
 733                         c1 = c1 - '0';
 734                 else if (c1 >= 'A' && c1 <= 'F')
 735                         c1 = 10 + c1 - 'A';
 736                 else if (c1 >= 'a' && c1 <= 'f')
 737                         c1 = 10 + c1 - 'a';
 738                 else {p++; continue;}
 739
 740                 if (c2 >= '0' && c2 <= '9')
 741                         c2 = c2 - '0';
 742                 else if (c2 >= 'A' && c2 <= 'F')
 743                         c2 = 10 + c2 - 'A';
 744                 else if (c2 >= 'a' && c2 <= 'f')
 745                         c2 = 10 + c2 - 'a';
 746                 else {p++; continue;}
 747
 748                 *p = (c1<<4) | c2;
 749
 750                 memmove(p+1, p+3, strlen(p+3)+1);
 751                 p++;
 752         }
 753 }
 754
 755 /**
 756   varient of strcmp() that handles NULL ptrs
 757 **/
 758 _PUBLIC_ int strcmp_safe(const char *s1, const char *s2)
 759 {
 760         if (s1 == s2) {
 761                 return 0;
 762         }
 763         if (s1 == NULL || s2 == NULL) {
 764                 return s1?-1:1;
 765         }
 766         return strcmp(s1, s2);
 767 }
 768
 769
 770 /**
 771 return the number of bytes occupied by a buffer in ASCII format
 772 the result includes the null termination
 773 limited by 'n' bytes
 774 **/
 775 _PUBLIC_ size_t ascii_len_n(const char *src, size_t n)
 776 {
 777         size_t len;
 778
 779         len = strnlen(src, n);
 780         if (len+1 <= n) {
 781                 len += 1;
 782         }
 783
 784         return len;
 785 }
 786
 787 /**
 788  Set a boolean variable from the text value stored in the passed string.
 789  Returns true in success, false if the passed string does not correctly
 790  represent a boolean.
 791 **/
 792
 793 _PUBLIC_ bool set_boolean(const char *boolean_string, bool *boolean)
 794 {
 795         if (strwicmp(boolean_string, "yes") == 0 ||
 796             strwicmp(boolean_string, "true") == 0 ||
 797             strwicmp(boolean_string, "on") == 0 ||
 798             strwicmp(boolean_string, "1") == 0) {
 799                 *boolean = true;
 800                 return true;
 801         } else if (strwicmp(boolean_string, "no") == 0 ||
 802                    strwicmp(boolean_string, "false") == 0 ||
 803                    strwicmp(boolean_string, "off") == 0 ||
 804                    strwicmp(boolean_string, "0") == 0) {
 805                 *boolean = false;
 806                 return true;
 807         }
 808         return false;
 809 }
 810
 811 /**
 812 return the number of bytes occupied by a buffer in CH_UTF16 format
 813 the result includes the null termination
 814 **/
 815 _PUBLIC_ size_t utf16_len(const void *buf)
 816 {
 817         size_t len;
 818
 819         for (len = 0; SVAL(buf,len); len += 2) ;
 820
 821         return len + 2;
 822 }
 823
 824 /**
 825 return the number of bytes occupied by a buffer in CH_UTF16 format
 826 the result includes the null termination
 827 limited by 'n' bytes
 828 **/
 829 _PUBLIC_ size_t utf16_len_n(const void *src, size_t n)
 830 {
 831         size_t len;
 832
 833         for (len = 0; (len+2 < n) && SVAL(src, len); len += 2) ;
 834
 835         if (len+2 <= n) {
 836                 len += 2;
 837         }
 838
 839         return len;
 840 }
 841
 842