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 2001-2011
   7    Copyright (C) Jim McDonough (jmcd@us.ibm.com)  2003.
   8    Copyright (C) James J Myers 2003
   9    Copyright (C) Volker Lendecke 2010
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "includes.h"
  26 #include "system/network.h"
  27 #include "system/filesys.h"
  28 #include "system/locale.h"
  29 #include "system/shmem.h"
  30 #include "system/passwd.h"
  31
  32 #undef malloc
  33 #undef strcasecmp
  34 #undef strncasecmp
  35 #undef strdup
  36 #undef realloc
  37
  38 /**
  39  * @file
  40  * @brief Misc utility functions
  41  */
  42
  43 /**
  44  Find a suitable temporary directory. The result should be copied immediately
  45  as it may be overwritten by a subsequent call.
  46 **/
  47 _PUBLIC_ const char *tmpdir(void)
  48 {
  49         char *p;
  50         if ((p = getenv("TMPDIR")))
  51                 return p;
  52         return "/tmp";
  53 }
  54
  55
  56 /**
  57  Create a tmp file, open it and immediately unlink it.
  58  If dir is NULL uses tmpdir()
  59  Returns the file descriptor or -1 on error.
  60 **/
  61 int create_unlink_tmp(const char *dir)
  62 {
  63         char *fname;
  64         int fd;
  65
  66         if (!dir) {
  67                 dir = tmpdir();
  68         }
  69
  70         fname = talloc_asprintf(talloc_tos(), "%s/listenerlock_XXXXXX", dir);
  71         if (fname == NULL) {
  72                 errno = ENOMEM;
  73                 return -1;
  74         }
  75         fd = mkstemp(fname);
  76         if (fd == -1) {
  77                 TALLOC_FREE(fname);
  78                 return -1;
  79         }
  80         if (unlink(fname) == -1) {
  81                 int sys_errno = errno;
  82                 close(fd);
  83                 TALLOC_FREE(fname);
  84                 errno = sys_errno;
  85                 return -1;
  86         }
  87         TALLOC_FREE(fname);
  88         return fd;
  89 }
  90
  91
  92 /**
  93  Check if a file exists - call vfs_file_exist for samba files.
  94 **/
  95 _PUBLIC_ bool file_exist(const char *fname)
  96 {
  97         struct stat st;
  98
  99         if (stat(fname, &st) != 0) {
 100                 return false;
 101         }
 102
 103         return ((S_ISREG(st.st_mode)) || (S_ISFIFO(st.st_mode)));
 104 }
 105
 106 /**
 107  Check a files mod time.
 108 **/
 109
 110 _PUBLIC_ time_t file_modtime(const char *fname)
 111 {
 112         struct stat st;
 113
 114         if (stat(fname,&st) != 0)
 115                 return(0);
 116
 117         return(st.st_mtime);
 118 }
 119
 120 /**
 121  Check if a directory exists.
 122 **/
 123
 124 _PUBLIC_ bool directory_exist(const char *dname)
 125 {
 126         struct stat st;
 127         bool ret;
 128
 129         if (stat(dname,&st) != 0) {
 130                 return false;
 131         }
 132
 133         ret = S_ISDIR(st.st_mode);
 134         if(!ret)
 135                 errno = ENOTDIR;
 136         return ret;
 137 }
 138
 139 /**
 140  * Try to create the specified directory if it didn't exist.
 141  *
 142  * @retval true if the directory already existed and has the right permissions
 143  * or was successfully created.
 144  */
 145 _PUBLIC_ bool directory_create_or_exist(const char *dname, uid_t uid,
 146                                mode_t dir_perms)
 147 {
 148         mode_t old_umask;
 149         struct stat st;
 150
 151         old_umask = umask(0);
 152         if (lstat(dname, &st) == -1) {
 153                 if (errno == ENOENT) {
 154                         /* Create directory */
 155                         if (mkdir(dname, dir_perms) == -1) {
 156                                 DEBUG(0, ("error creating directory "
 157                                           "%s: %s\n", dname,
 158                                           strerror(errno)));
 159                                 umask(old_umask);
 160                                 return false;
 161                         }
 162                 } else {
 163                         DEBUG(0, ("lstat failed on directory %s: %s\n",
 164                                   dname, strerror(errno)));
 165                         umask(old_umask);
 166                         return false;
 167                 }
 168         } else {
 169                 /* Check ownership and permission on existing directory */
 170                 if (!S_ISDIR(st.st_mode)) {
 171                         DEBUG(0, ("directory %s isn't a directory\n",
 172                                 dname));
 173                         umask(old_umask);
 174                         return false;
 175                 }
 176                 if (st.st_uid != uid && !uwrap_enabled()) {
 177                         DEBUG(0, ("invalid ownership on directory "
 178                                   "%s\n", dname));
 179                         umask(old_umask);
 180                         return false;
 181                 }
 182                 if ((st.st_mode & 0777) != dir_perms) {
 183                         DEBUG(0, ("invalid permissions on directory "
 184                                   "'%s': has 0%o should be 0%o\n", dname,
 185                                   (st.st_mode & 0777), dir_perms));
 186                         umask(old_umask);
 187                         return false;
 188                 }
 189         }
 190         return true;
 191 }
 192
 193
 194 /**
 195  Sleep for a specified number of milliseconds.
 196 **/
 197
 198 _PUBLIC_ void smb_msleep(unsigned int t)
 199 {
 200 #if defined(HAVE_NANOSLEEP)
 201         struct timespec ts;
 202         int ret;
 203
 204         ts.tv_sec = t/1000;
 205         ts.tv_nsec = 1000000*(t%1000);
 206
 207         do {
 208                 errno = 0;
 209                 ret = nanosleep(&ts, &ts);
 210         } while (ret < 0 && errno == EINTR && (ts.tv_sec > 0 || ts.tv_nsec > 0));
 211 #else
 212         unsigned int tdiff=0;
 213         struct timeval tval,t1,t2;
 214         fd_set fds;
 215
 216         GetTimeOfDay(&t1);
 217         t2 = t1;
 218
 219         while (tdiff < t) {
 220                 tval.tv_sec = (t-tdiff)/1000;
 221                 tval.tv_usec = 1000*((t-tdiff)%1000);
 222
 223                 /* Never wait for more than 1 sec. */
 224                 if (tval.tv_sec > 1) {
 225                         tval.tv_sec = 1;
 226                         tval.tv_usec = 0;
 227                 }
 228
 229                 FD_ZERO(&fds);
 230                 errno = 0;
 231                 select(0,&fds,NULL,NULL,&tval);
 232
 233                 GetTimeOfDay(&t2);
 234                 if (t2.tv_sec < t1.tv_sec) {
 235                         /* Someone adjusted time... */
 236                         t1 = t2;
 237                 }
 238
 239                 tdiff = usec_time_diff(&t2,&t1)/1000;
 240         }
 241 #endif
 242 }
 243
 244 /**
 245  Get my own name, return in talloc'ed storage.
 246 **/
 247
 248 _PUBLIC_ char *get_myname(TALLOC_CTX *ctx)
 249 {
 250         char *p;
 251         char hostname[HOST_NAME_MAX];
 252
 253         /* get my host name */
 254         if (gethostname(hostname, sizeof(hostname)) == -1) {
 255                 DEBUG(0,("gethostname failed\n"));
 256                 return NULL;
 257         }
 258
 259         /* Ensure null termination. */
 260         hostname[sizeof(hostname)-1] = '\0';
 261
 262         /* split off any parts after an initial . */
 263         p = strchr_m(hostname, '.');
 264         if (p) {
 265                 *p = 0;
 266         }
 267
 268         return talloc_strdup(ctx, hostname);
 269 }
 270
 271 /**
 272  Check if a process exists. Does this work on all unixes?
 273 **/
 274
 275 _PUBLIC_ bool process_exists_by_pid(pid_t pid)
 276 {
 277         /* Doing kill with a non-positive pid causes messages to be
 278          * sent to places we don't want. */
 279         SMB_ASSERT(pid > 0);
 280         return(kill(pid,0) == 0 || errno != ESRCH);
 281 }
 282
 283 /**
 284  Simple routine to do POSIX file locking. Cruft in NFS and 64->32 bit mapping
 285  is dealt with in posix.c
 286 **/
 287
 288 _PUBLIC_ bool fcntl_lock(int fd, int op, off_t offset, off_t count, int type)
 289 {
 290         struct flock lock;
 291         int ret;
 292
 293         DEBUG(8,("fcntl_lock %d %d %.0f %.0f %d\n",fd,op,(double)offset,(double)count,type));
 294
 295         lock.l_type = type;
 296         lock.l_whence = SEEK_SET;
 297         lock.l_start = offset;
 298         lock.l_len = count;
 299         lock.l_pid = 0;
 300
 301         ret = fcntl(fd,op,&lock);
 302
 303         if (ret == -1 && errno != 0)
 304                 DEBUG(3,("fcntl_lock: fcntl lock gave errno %d (%s)\n",errno,strerror(errno)));
 305
 306         /* a lock query */
 307         if (op == F_GETLK) {
 308                 if ((ret != -1) &&
 309                                 (lock.l_type != F_UNLCK) &&
 310                                 (lock.l_pid != 0) &&
 311                                 (lock.l_pid != getpid())) {
 312                         DEBUG(3,("fcntl_lock: fd %d is locked by pid %d\n",fd,(int)lock.l_pid));
 313                         return true;
 314                 }
 315
 316                 /* it must be not locked or locked by me */
 317                 return false;
 318         }
 319
 320         /* a lock set or unset */
 321         if (ret == -1) {
 322                 DEBUG(3,("fcntl_lock: lock failed at offset %.0f count %.0f op %d type %d (%s)\n",
 323                         (double)offset,(double)count,op,type,strerror(errno)));
 324                 return false;
 325         }
 326
 327         /* everything went OK */
 328         DEBUG(8,("fcntl_lock: Lock call successful\n"));
 329
 330         return true;
 331 }
 332
 333 static void debugadd_cb(const char *buf, void *private_data)
 334 {
 335         int *plevel = (int *)private_data;
 336         DEBUGADD(*plevel, ("%s", buf));
 337 }
 338
 339 void print_asc_cb(const uint8_t *buf, int len,
 340                   void (*cb)(const char *buf, void *private_data),
 341                   void *private_data)
 342 {
 343         int i;
 344         char s[2];
 345         s[1] = 0;
 346
 347         for (i=0; i<len; i++) {
 348                 s[0] = isprint(buf[i]) ? buf[i] : '.';
 349                 cb(s, private_data);
 350         }
 351 }
 352
 353 void print_asc(int level, const uint8_t *buf,int len)
 354 {
 355         print_asc_cb(buf, len, debugadd_cb, &level);
 356 }
 357
 358 /**
 359  * Write dump of binary data to a callback
 360  */
 361 void dump_data_cb(const uint8_t *buf, int len,
 362                   bool omit_zero_bytes,
 363                   void (*cb)(const char *buf, void *private_data),
 364                   void *private_data)
 365 {
 366         int i=0;
 367         static const uint8_t empty[16] = { 0, };
 368         bool skipped = false;
 369         char tmp[16];
 370
 371         if (len<=0) return;
 372
 373         for (i=0;i<len;) {
 374
 375                 if (i%16 == 0) {
 376                         if ((omit_zero_bytes == true) &&
 377                             (i > 0) &&
 378                             (len > i+16) &&
 379                             (memcmp(&buf[i], &empty, 16) == 0))
 380                         {
 381                                 i +=16;
 382                                 continue;
 383                         }
 384
 385                         if (i<len)  {
 386                                 snprintf(tmp, sizeof(tmp), "[%04X] ", i);
 387                                 cb(tmp, private_data);
 388                         }
 389                 }
 390
 391                 snprintf(tmp, sizeof(tmp), "%02X ", (int)buf[i]);
 392                 cb(tmp, private_data);
 393                 i++;
 394                 if (i%8 == 0) {
 395                         cb("  ", private_data);
 396                 }
 397                 if (i%16 == 0) {
 398
 399                         print_asc_cb(&buf[i-16], 8, cb, private_data);
 400                         cb(" ", private_data);
 401                         print_asc_cb(&buf[i-8], 8, cb, private_data);
 402                         cb("\n", private_data);
 403
 404                         if ((omit_zero_bytes == true) &&
 405                             (len > i+16) &&
 406                             (memcmp(&buf[i], &empty, 16) == 0)) {
 407                                 if (!skipped) {
 408                                         cb("skipping zero buffer bytes\n",
 409                                            private_data);
 410                                         skipped = true;
 411                                 }
 412                         }
 413                 }
 414         }
 415
 416         if (i%16) {
 417                 int n;
 418                 n = 16 - (i%16);
 419                 cb(" ", private_data);
 420                 if (n>8) {
 421                         cb(" ", private_data);
 422                 }
 423                 while (n--) {
 424                         cb("   ", private_data);
 425                 }
 426                 n = MIN(8,i%16);
 427                 print_asc_cb(&buf[i-(i%16)], n, cb, private_data);
 428                 cb(" ", private_data);
 429                 n = (i%16) - n;
 430                 if (n>0) {
 431                         print_asc_cb(&buf[i-n], n, cb, private_data);
 432                 }
 433                 cb("\n", private_data);
 434         }
 435
 436 }
 437
 438 /**
 439  * Write dump of binary data to the log file.
 440  *
 441  * The data is only written if the log level is at least level.
 442  */
 443 _PUBLIC_ void dump_data(int level, const uint8_t *buf, int len)
 444 {
 445         if (!DEBUGLVL(level)) {
 446                 return;
 447         }
 448         dump_data_cb(buf, len, false, debugadd_cb, &level);
 449 }
 450
 451 /**
 452  * Write dump of binary data to the log file.
 453  *
 454  * The data is only written if the log level is at least level.
 455  * 16 zero bytes in a row are omitted
 456  */
 457 _PUBLIC_ void dump_data_skip_zeros(int level, const uint8_t *buf, int len)
 458 {
 459         if (!DEBUGLVL(level)) {
 460                 return;
 461         }
 462         dump_data_cb(buf, len, true, debugadd_cb, &level);
 463 }
 464
 465
 466 /**
 467  malloc that aborts with smb_panic on fail or zero size.
 468 **/
 469
 470 _PUBLIC_ void *smb_xmalloc(size_t size)
 471 {
 472         void *p;
 473         if (size == 0)
 474                 smb_panic("smb_xmalloc: called with zero size.\n");
 475         if ((p = malloc(size)) == NULL)
 476                 smb_panic("smb_xmalloc: malloc fail.\n");
 477         return p;
 478 }
 479
 480 /**
 481  Memdup with smb_panic on fail.
 482 **/
 483
 484 _PUBLIC_ void *smb_xmemdup(const void *p, size_t size)
 485 {
 486         void *p2;
 487         p2 = smb_xmalloc(size);
 488         memcpy(p2, p, size);
 489         return p2;
 490 }
 491
 492 /**
 493  strdup that aborts on malloc fail.
 494 **/
 495
 496 char *smb_xstrdup(const char *s)
 497 {
 498 #if defined(PARANOID_MALLOC_CHECKER)
 499 #ifdef strdup
 500 #undef strdup
 501 #endif
 502 #endif
 503
 504 #ifndef HAVE_STRDUP
 505 #define strdup rep_strdup
 506 #endif
 507
 508         char *s1 = strdup(s);
 509 #if defined(PARANOID_MALLOC_CHECKER)
 510 #ifdef strdup
 511 #undef strdup
 512 #endif
 513 #define strdup(s) __ERROR_DONT_USE_STRDUP_DIRECTLY
 514 #endif
 515         if (!s1) {
 516                 smb_panic("smb_xstrdup: malloc failed");
 517         }
 518         return s1;
 519
 520 }
 521
 522 /**
 523  strndup that aborts on malloc fail.
 524 **/
 525
 526 char *smb_xstrndup(const char *s, size_t n)
 527 {
 528 #if defined(PARANOID_MALLOC_CHECKER)
 529 #ifdef strndup
 530 #undef strndup
 531 #endif
 532 #endif
 533
 534 #if (defined(BROKEN_STRNDUP) || !defined(HAVE_STRNDUP))
 535 #undef HAVE_STRNDUP
 536 #define strndup rep_strndup
 537 #endif
 538
 539         char *s1 = strndup(s, n);
 540 #if defined(PARANOID_MALLOC_CHECKER)
 541 #ifdef strndup
 542 #undef strndup
 543 #endif
 544 #define strndup(s,n) __ERROR_DONT_USE_STRNDUP_DIRECTLY
 545 #endif
 546         if (!s1) {
 547                 smb_panic("smb_xstrndup: malloc failed");
 548         }
 549         return s1;
 550 }
 551
 552
 553
 554 /**
 555  Like strdup but for memory.
 556 **/
 557
 558 _PUBLIC_ void *memdup(const void *p, size_t size)
 559 {
 560         void *p2;
 561         if (size == 0)
 562                 return NULL;
 563         p2 = malloc(size);
 564         if (!p2)
 565                 return NULL;
 566         memcpy(p2, p, size);
 567         return p2;
 568 }
 569
 570 /**
 571  * Write a password to the log file.
 572  *
 573  * @note Only actually does something if DEBUG_PASSWORD was defined during
 574  * compile-time.
 575  */
 576 _PUBLIC_ void dump_data_pw(const char *msg, const uint8_t * data, size_t len)
 577 {
 578 #ifdef DEBUG_PASSWORD
 579         DEBUG(11, ("%s", msg));
 580         if (data != NULL && len > 0)
 581         {
 582                 dump_data(11, data, len);
 583         }
 584 #endif
 585 }
 586
 587
 588 /**
 589  * see if a range of memory is all zero. A NULL pointer is considered
 590  * to be all zero
 591  */
 592 _PUBLIC_ bool all_zero(const uint8_t *ptr, size_t size)
 593 {
 594         int i;
 595         if (!ptr) return true;
 596         for (i=0;i<size;i++) {
 597                 if (ptr[i]) return false;
 598         }
 599         return true;
 600 }
 601
 602 /**
 603   realloc an array, checking for integer overflow in the array size
 604 */
 605 _PUBLIC_ void *realloc_array(void *ptr, size_t el_size, unsigned count, bool free_on_fail)
 606 {
 607 #define MAX_MALLOC_SIZE 0x7fffffff
 608         if (count == 0 ||
 609             count >= MAX_MALLOC_SIZE/el_size) {
 610                 if (free_on_fail)
 611                         SAFE_FREE(ptr);
 612                 return NULL;
 613         }
 614         if (!ptr) {
 615                 return malloc(el_size * count);
 616         }
 617         return realloc(ptr, el_size * count);
 618 }
 619
 620 /****************************************************************************
 621  Type-safe malloc.
 622 ****************************************************************************/
 623
 624 void *malloc_array(size_t el_size, unsigned int count)
 625 {
 626         return realloc_array(NULL, el_size, count, false);
 627 }
 628
 629 /**
 630  Trim the specified elements off the front and back of a string.
 631 **/
 632 _PUBLIC_ bool trim_string(char *s, const char *front, const char *back)
 633 {
 634         bool ret = false;
 635         size_t front_len;
 636         size_t back_len;
 637         size_t len;
 638
 639         /* Ignore null or empty strings. */
 640         if (!s || (s[0] == '\0'))
 641                 return false;
 642
 643         front_len       = front? strlen(front) : 0;
 644         back_len        = back? strlen(back) : 0;
 645
 646         len = strlen(s);
 647
 648         if (front_len) {
 649                 while (len && strncmp(s, front, front_len)==0) {
 650                         /* Must use memmove here as src & dest can
 651                          * easily overlap. Found by valgrind. JRA. */
 652                         memmove(s, s+front_len, (len-front_len)+1);
 653                         len -= front_len;
 654                         ret=true;
 655                 }
 656         }
 657
 658         if (back_len) {
 659                 while ((len >= back_len) && strncmp(s+len-back_len,back,back_len)==0) {
 660                         s[len-back_len]='\0';
 661                         len -= back_len;
 662                         ret=true;
 663                 }
 664         }
 665         return ret;
 666 }
 667
 668 /**
 669  Find the number of 'c' chars in a string
 670 **/
 671 _PUBLIC_ _PURE_ size_t count_chars(const char *s, char c)
 672 {
 673         size_t count = 0;
 674
 675         while (*s) {
 676                 if (*s == c) count++;
 677                 s ++;
 678         }
 679
 680         return count;
 681 }
 682
 683 /**
 684  * Routine to get hex characters and turn them into a byte array.
 685  * the array can be variable length.
 686  * -  "0xnn" or "0Xnn" is specially catered for.
 687  * - The first non-hex-digit character (apart from possibly leading "0x"
 688  *   finishes the conversion and skips the rest of the input.
 689  * - A single hex-digit character at the end of the string is skipped.
 690  *
 691  * valid examples: "0A5D15"; "0x123456"
 692  */
 693 _PUBLIC_ size_t strhex_to_str(char *p, size_t p_len, const char *strhex, size_t strhex_len)
 694 {
 695         size_t i = 0;
 696         size_t num_chars = 0;
 697         uint8_t   lonybble, hinybble;
 698         const char     *hexchars = "0123456789ABCDEF";
 699         char           *p1 = NULL, *p2 = NULL;
 700
 701         /* skip leading 0x prefix */
 702         if (strncasecmp(strhex, "0x", 2) == 0) {
 703                 i += 2; /* skip two chars */
 704         }
 705
 706         for (; i+1 < strhex_len && strhex[i] != 0 && strhex[i+1] != 0; i++) {
 707                 p1 = strchr(hexchars, toupper((unsigned char)strhex[i]));
 708                 if (p1 == NULL) {
 709                         break;
 710                 }
 711
 712                 i++; /* next hex digit */
 713
 714                 p2 = strchr(hexchars, toupper((unsigned char)strhex[i]));
 715                 if (p2 == NULL) {
 716                         break;
 717                 }
 718
 719                 /* get the two nybbles */
 720                 hinybble = PTR_DIFF(p1, hexchars);
 721                 lonybble = PTR_DIFF(p2, hexchars);
 722
 723                 if (num_chars >= p_len) {
 724                         break;
 725                 }
 726
 727                 p[num_chars] = (hinybble << 4) | lonybble;
 728                 num_chars++;
 729
 730                 p1 = NULL;
 731                 p2 = NULL;
 732         }
 733         return num_chars;
 734 }
 735
 736 /**
 737  * Parse a hex string and return a data blob.
 738  */
 739 _PUBLIC_ _PURE_ DATA_BLOB strhex_to_data_blob(TALLOC_CTX *mem_ctx, const char *strhex)
 740 {
 741         DATA_BLOB ret_blob = data_blob_talloc(mem_ctx, NULL, strlen(strhex)/2+1);
 742
 743         ret_blob.length = strhex_to_str((char *)ret_blob.data, ret_blob.length,
 744                                         strhex,
 745                                         strlen(strhex));
 746
 747         return ret_blob;
 748 }
 749
 750
 751 /**
 752  * Routine to print a buffer as HEX digits, into an allocated string.
 753  */
 754 _PUBLIC_ void hex_encode(const unsigned char *buff_in, size_t len, char **out_hex_buffer)
 755 {
 756         int i;
 757         char *hex_buffer;
 758
 759         *out_hex_buffer = malloc_array_p(char, (len*2)+1);
 760         hex_buffer = *out_hex_buffer;
 761
 762         for (i = 0; i < len; i++)
 763                 slprintf(&hex_buffer[i*2], 3, "%02X", buff_in[i]);
 764 }
 765
 766 /**
 767  * talloc version of hex_encode()
 768  */
 769 _PUBLIC_ char *hex_encode_talloc(TALLOC_CTX *mem_ctx, const unsigned char *buff_in, size_t len)
 770 {
 771         int i;
 772         char *hex_buffer;
 773
 774         hex_buffer = talloc_array(mem_ctx, char, (len*2)+1);
 775         if (!hex_buffer) {
 776                 return NULL;
 777         }
 778
 779         for (i = 0; i < len; i++)
 780                 slprintf(&hex_buffer[i*2], 3, "%02X", buff_in[i]);
 781
 782         talloc_set_name_const(hex_buffer, hex_buffer);
 783         return hex_buffer;
 784 }
 785
 786 /**
 787   varient of strcmp() that handles NULL ptrs
 788 **/
 789 _PUBLIC_ int strcmp_safe(const char *s1, const char *s2)
 790 {
 791         if (s1 == s2) {
 792                 return 0;
 793         }
 794         if (s1 == NULL || s2 == NULL) {
 795                 return s1?-1:1;
 796         }
 797         return strcmp(s1, s2);
 798 }
 799
 800
 801 /**
 802 return the number of bytes occupied by a buffer in ASCII format
 803 the result includes the null termination
 804 limited by 'n' bytes
 805 **/
 806 _PUBLIC_ size_t ascii_len_n(const char *src, size_t n)
 807 {
 808         size_t len;
 809
 810         len = strnlen(src, n);
 811         if (len+1 <= n) {
 812                 len += 1;
 813         }
 814
 815         return len;
 816 }
 817
 818 /**
 819  Set a boolean variable from the text value stored in the passed string.
 820  Returns true in success, false if the passed string does not correctly
 821  represent a boolean.
 822 **/
 823
 824 _PUBLIC_ bool set_boolean(const char *boolean_string, bool *boolean)
 825 {
 826         if (strwicmp(boolean_string, "yes") == 0 ||
 827             strwicmp(boolean_string, "true") == 0 ||
 828             strwicmp(boolean_string, "on") == 0 ||
 829             strwicmp(boolean_string, "1") == 0) {
 830                 *boolean = true;
 831                 return true;
 832         } else if (strwicmp(boolean_string, "no") == 0 ||
 833                    strwicmp(boolean_string, "false") == 0 ||
 834                    strwicmp(boolean_string, "off") == 0 ||
 835                    strwicmp(boolean_string, "0") == 0) {
 836                 *boolean = false;
 837                 return true;
 838         }
 839         return false;
 840 }
 841
 842 /**
 843 return the number of bytes occupied by a buffer in CH_UTF16 format
 844 the result includes the null termination
 845 **/
 846 _PUBLIC_ size_t utf16_len(const void *buf)
 847 {
 848         size_t len;
 849
 850         for (len = 0; SVAL(buf,len); len += 2) ;
 851
 852         return len + 2;
 853 }
 854
 855 /**
 856 return the number of bytes occupied by a buffer in CH_UTF16 format
 857 the result includes the null termination
 858 limited by 'n' bytes
 859 **/
 860 _PUBLIC_ size_t utf16_len_n(const void *src, size_t n)
 861 {
 862         size_t len;
 863
 864         for (len = 0; (len+2 < n) && SVAL(src, len); len += 2) ;
 865
 866         if (len+2 <= n) {
 867                 len += 2;
 868         }
 869
 870         return len;
 871 }
 872
 873 /**
 874  * @file
 875  * @brief String utilities.
 876  **/
 877
 878 static bool next_token_internal_talloc(TALLOC_CTX *ctx,
 879                                 const char **ptr,
 880                                 char **pp_buff,
 881                                 const char *sep,
 882                                 bool ltrim)
 883 {
 884         const char *s;
 885         const char *saved_s;
 886         char *pbuf;
 887         bool quoted;
 888         size_t len=1;
 889
 890         *pp_buff = NULL;
 891         if (!ptr) {
 892                 return(false);
 893         }
 894
 895         s = *ptr;
 896
 897         /* default to simple separators */
 898         if (!sep) {
 899                 sep = " \t\n\r";
 900         }
 901
 902         /* find the first non sep char, if left-trimming is requested */
 903         if (ltrim) {
 904                 while (*s && strchr_m(sep,*s)) {
 905                         s++;
 906                 }
 907         }
 908
 909         /* nothing left? */
 910         if (!*s) {
 911                 return false;
 912         }
 913
 914         /* When restarting we need to go from here. */
 915         saved_s = s;
 916
 917         /* Work out the length needed. */
 918         for (quoted = false; *s &&
 919                         (quoted || !strchr_m(sep,*s)); s++) {
 920                 if (*s == '\"') {
 921                         quoted = !quoted;
 922                 } else {
 923                         len++;
 924                 }
 925         }
 926
 927         /* We started with len = 1 so we have space for the nul. */
 928         *pp_buff = talloc_array(ctx, char, len);
 929         if (!*pp_buff) {
 930                 return false;
 931         }
 932
 933         /* copy over the token */
 934         pbuf = *pp_buff;
 935         s = saved_s;
 936         for (quoted = false; *s &&
 937                         (quoted || !strchr_m(sep,*s)); s++) {
 938                 if ( *s == '\"' ) {
 939                         quoted = !quoted;
 940                 } else {
 941                         *pbuf++ = *s;
 942                 }
 943         }
 944
 945         *ptr = (*s) ? s+1 : s;
 946         *pbuf = 0;
 947
 948         return true;
 949 }
 950
 951 bool next_token_talloc(TALLOC_CTX *ctx,
 952                         const char **ptr,
 953                         char **pp_buff,
 954                         const char *sep)
 955 {
 956         return next_token_internal_talloc(ctx, ptr, pp_buff, sep, true);
 957 }
 958
 959 /*
 960  * Get the next token from a string, return false if none found.  Handles
 961  * double-quotes.  This version does not trim leading separator characters
 962  * before looking for a token.
 963  */
 964
 965 bool next_token_no_ltrim_talloc(TALLOC_CTX *ctx,
 966                         const char **ptr,
 967                         char **pp_buff,
 968                         const char *sep)
 969 {
 970         return next_token_internal_talloc(ctx, ptr, pp_buff, sep, false);
 971 }
 972
 973 /**
 974  * Get the next token from a string, return False if none found.
 975  * Handles double-quotes.
 976  *
 977  * Based on a routine by GJC@VILLAGE.COM.
 978  * Extensively modified by Andrew.Tridgell@anu.edu.au
 979  **/
 980 _PUBLIC_ bool next_token(const char **ptr,char *buff, const char *sep, size_t bufsize)
 981 {
 982         const char *s;
 983         bool quoted;
 984         size_t len=1;
 985
 986         if (!ptr)
 987                 return false;
 988
 989         s = *ptr;
 990
 991         /* default to simple separators */
 992         if (!sep)
 993                 sep = " \t\n\r";
 994
 995         /* find the first non sep char */
 996         while (*s && strchr_m(sep,*s))
 997                 s++;
 998
 999         /* nothing left? */
1000         if (!*s)
1001                 return false;
1002
1003         /* copy over the token */
1004         for (quoted = false; len < bufsize && *s && (quoted || !strchr_m(sep,*s)); s++) {
1005                 if (*s == '\"') {
1006                         quoted = !quoted;
1007                 } else {
1008                         len++;
1009                         *buff++ = *s;
1010                 }
1011         }
1012
1013         *ptr = (*s) ? s+1 : s;
1014         *buff = 0;
1015
1016         return true;
1017 }
1018
1019 struct anonymous_shared_header {
1020         union {
1021                 size_t length;
1022                 uint8_t pad[16];
1023         } u;
1024 };
1025
1026 /* Map a shared memory buffer of at least nelem counters. */
1027 void *anonymous_shared_allocate(size_t orig_bufsz)
1028 {
1029         void *ptr;
1030         void *buf;
1031         size_t pagesz = getpagesize();
1032         size_t pagecnt;
1033         size_t bufsz = orig_bufsz;
1034         struct anonymous_shared_header *hdr;
1035
1036         bufsz += sizeof(*hdr);
1037
1038         /* round up to full pages */
1039         pagecnt = bufsz / pagesz;
1040         if (bufsz % pagesz) {
1041                 pagecnt += 1;
1042         }
1043         bufsz = pagesz * pagecnt;
1044
1045         if (orig_bufsz >= bufsz) {
1046                 /* integer wrap */
1047                 errno = ENOMEM;
1048                 return NULL;
1049         }
1050
1051 #ifdef MAP_ANON
1052         /* BSD */
1053         buf = mmap(NULL, bufsz, PROT_READ|PROT_WRITE, MAP_ANON|MAP_SHARED,
1054                         -1 /* fd */, 0 /* offset */);
1055 #else
1056         buf = mmap(NULL, bufsz, PROT_READ|PROT_WRITE, MAP_FILE|MAP_SHARED,
1057                         open("/dev/zero", O_RDWR), 0 /* offset */);
1058 #endif
1059
1060         if (buf == MAP_FAILED) {
1061                 return NULL;
1062         }
1063
1064         hdr = (struct anonymous_shared_header *)buf;
1065         hdr->u.length = bufsz;
1066
1067         ptr = (void *)(&hdr[1]);
1068
1069         return ptr;
1070 }
1071
1072 void *anonymous_shared_resize(void *ptr, size_t new_size, bool maymove)
1073 {
1074 #ifdef HAVE_MREMAP
1075         void *buf;
1076         size_t pagesz = getpagesize();
1077         size_t pagecnt;
1078         size_t bufsz;
1079         struct anonymous_shared_header *hdr;
1080         int flags = 0;
1081
1082         if (ptr == NULL) {
1083                 errno = EINVAL;
1084                 return NULL;
1085         }
1086
1087         hdr = (struct anonymous_shared_header *)ptr;
1088         hdr--;
1089         if (hdr->u.length > (new_size + sizeof(*hdr))) {
1090                 errno = EINVAL;
1091                 return NULL;
1092         }
1093
1094         bufsz = new_size + sizeof(*hdr);
1095
1096         /* round up to full pages */
1097         pagecnt = bufsz / pagesz;
1098         if (bufsz % pagesz) {
1099                 pagecnt += 1;
1100         }
1101         bufsz = pagesz * pagecnt;
1102
1103         if (new_size >= bufsz) {
1104                 /* integer wrap */
1105                 errno = ENOSPC;
1106                 return NULL;
1107         }
1108
1109         if (bufsz <= hdr->u.length) {
1110                 return ptr;
1111         }
1112
1113         if (maymove) {
1114                 flags = MREMAP_MAYMOVE;
1115         }
1116
1117         buf = mremap(hdr, hdr->u.length, bufsz, flags);
1118
1119         if (buf == MAP_FAILED) {
1120                 errno = ENOSPC;
1121                 return NULL;
1122         }
1123
1124         hdr = (struct anonymous_shared_header *)buf;
1125         hdr->u.length = bufsz;
1126
1127         ptr = (void *)(&hdr[1]);
1128
1129         return ptr;
1130 #else
1131         errno = ENOSPC;
1132         return NULL;
1133 #endif
1134 }
1135
1136 void anonymous_shared_free(void *ptr)
1137 {
1138         struct anonymous_shared_header *hdr;
1139
1140         if (ptr == NULL) {
1141                 return;
1142         }
1143
1144         hdr = (struct anonymous_shared_header *)ptr;
1145
1146         hdr--;
1147
1148         munmap(hdr, hdr->u.length);
1149 }
1150
1151 #ifdef DEVELOPER
1152 /* used when you want a debugger started at a particular point in the
1153    code. Mostly useful in code that runs as a child process, where
1154    normal gdb attach is harder to organise.
1155 */
1156 void samba_start_debugger(void)
1157 {
1158         char *cmd = NULL;
1159         if (asprintf(&cmd, "xterm -e \"gdb --pid %u\"&", getpid()) == -1) {
1160                 return;
1161         }
1162         if (system(cmd) == -1) {
1163                 free(cmd);
1164                 return;
1165         }
1166         free(cmd);
1167         sleep(2);
1168 }
1169 #endif