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 #undef calloc
  38
  39 /**
  40  * @file
  41  * @brief Misc utility functions
  42  */
  43
  44 /**
  45  Find a suitable temporary directory. The result should be copied immediately
  46  as it may be overwritten by a subsequent call.
  47 **/
  48 _PUBLIC_ const char *tmpdir(void)
  49 {
  50         char *p;
  51         if ((p = getenv("TMPDIR")))
  52                 return p;
  53         return "/tmp";
  54 }
  55
  56
  57 /**
  58  Create a tmp file, open it and immediately unlink it.
  59  If dir is NULL uses tmpdir()
  60  Returns the file descriptor or -1 on error.
  61 **/
  62 int create_unlink_tmp(const char *dir)
  63 {
  64         char *fname;
  65         int fd;
  66         mode_t mask;
  67
  68         if (!dir) {
  69                 dir = tmpdir();
  70         }
  71
  72         fname = talloc_asprintf(talloc_tos(), "%s/listenerlock_XXXXXX", dir);
  73         if (fname == NULL) {
  74                 errno = ENOMEM;
  75                 return -1;
  76         }
  77         mask = umask(S_IRWXO | S_IRWXG);
  78         fd = mkstemp(fname);
  79         umask(mask);
  80         if (fd == -1) {
  81                 TALLOC_FREE(fname);
  82                 return -1;
  83         }
  84         if (unlink(fname) == -1) {
  85                 int sys_errno = errno;
  86                 close(fd);
  87                 TALLOC_FREE(fname);
  88                 errno = sys_errno;
  89                 return -1;
  90         }
  91         TALLOC_FREE(fname);
  92         return fd;
  93 }
  94
  95
  96 /**
  97  Check if a file exists - call vfs_file_exist for samba files.
  98 **/
  99 _PUBLIC_ bool file_exist(const char *fname)
 100 {
 101         struct stat st;
 102
 103         if (stat(fname, &st) != 0) {
 104                 return false;
 105         }
 106
 107         return ((S_ISREG(st.st_mode)) || (S_ISFIFO(st.st_mode)));
 108 }
 109
 110 /**
 111  Check a files mod time.
 112 **/
 113
 114 _PUBLIC_ time_t file_modtime(const char *fname)
 115 {
 116         struct stat st;
 117
 118         if (stat(fname,&st) != 0)
 119                 return(0);
 120
 121         return(st.st_mtime);
 122 }
 123
 124 /**
 125  Check if a directory exists.
 126 **/
 127
 128 _PUBLIC_ bool directory_exist(const char *dname)
 129 {
 130         struct stat st;
 131         bool ret;
 132
 133         if (stat(dname,&st) != 0) {
 134                 return false;
 135         }
 136
 137         ret = S_ISDIR(st.st_mode);
 138         if(!ret)
 139                 errno = ENOTDIR;
 140         return ret;
 141 }
 142
 143 /**
 144  * Try to create the specified directory if it didn't exist.
 145  *
 146  * @retval true if the directory already existed and has the right permissions
 147  * or was successfully created.
 148  */
 149 _PUBLIC_ bool directory_create_or_exist(const char *dname,
 150                                         uid_t uid,
 151                                         mode_t dir_perms)
 152 {
 153         int ret;
 154         struct stat st;
 155
 156         ret = lstat(dname, &st);
 157         if (ret == -1) {
 158                 mode_t old_umask;
 159
 160                 if (errno != ENOENT) {
 161                         DEBUG(0, ("lstat failed on directory %s: %s\n",
 162                                   dname, strerror(errno)));
 163                         return false;
 164                 }
 165
 166                 /* Create directory */
 167                 old_umask = umask(0);
 168                 ret = mkdir(dname, dir_perms);
 169                 if (ret == -1 && errno != EEXIST) {
 170                         DEBUG(0, ("mkdir failed on directory "
 171                                   "%s: %s\n", dname,
 172                                   strerror(errno)));
 173                         umask(old_umask);
 174                         return false;
 175                 }
 176                 umask(old_umask);
 177
 178                 ret = lstat(dname, &st);
 179                 if (ret == -1) {
 180                         DEBUG(0, ("lstat failed on created directory %s: %s\n",
 181                                   dname, strerror(errno)));
 182                         return false;
 183                 }
 184         }
 185
 186         return true;
 187 }
 188
 189 /**
 190  * @brief Try to create a specified directory if it doesn't exist.
 191  *
 192  * The function creates a directory with the given uid and permissions if it
 193  * doesn't exixt. If it exists it makes sure the uid and permissions are
 194  * correct and it will fail if they are different.
 195  *
 196  * @param[in]  dname  The directory to create.
 197  *
 198  * @param[in]  uid    The uid the directory needs to belong too.
 199  *
 200  * @param[in]  dir_perms  The expected permissions of the directory.
 201  *
 202  * @return True on success, false on error.
 203  */
 204 _PUBLIC_ bool directory_create_or_exist_strict(const char *dname,
 205                                                uid_t uid,
 206                                                mode_t dir_perms)
 207 {
 208         struct stat st;
 209         bool ok;
 210         int rc;
 211
 212         ok = directory_create_or_exist(dname, uid, dir_perms);
 213         if (!ok) {
 214                 return false;
 215         }
 216
 217         rc = lstat(dname, &st);
 218         if (rc == -1) {
 219                 DEBUG(0, ("lstat failed on created directory %s: %s\n",
 220                           dname, strerror(errno)));
 221                 return false;
 222         }
 223
 224         /* Check ownership and permission on existing directory */
 225         if (!S_ISDIR(st.st_mode)) {
 226                 DEBUG(0, ("directory %s isn't a directory\n",
 227                         dname));
 228                 return false;
 229         }
 230         if (st.st_uid != uid && !uwrap_enabled()) {
 231                 DEBUG(0, ("invalid ownership on directory "
 232                           "%s\n", dname));
 233                 return false;
 234         }
 235         if ((st.st_mode & 0777) != dir_perms) {
 236                 DEBUG(0, ("invalid permissions on directory "
 237                           "'%s': has 0%o should be 0%o\n", dname,
 238                           (unsigned int)(st.st_mode & 0777), (unsigned int)dir_perms));
 239                 return false;
 240         }
 241
 242         return true;
 243 }
 244
 245
 246 /**
 247  Sleep for a specified number of milliseconds.
 248 **/
 249
 250 _PUBLIC_ void smb_msleep(unsigned int t)
 251 {
 252 #if defined(HAVE_NANOSLEEP)
 253         struct timespec ts;
 254         int ret;
 255
 256         ts.tv_sec = t/1000;
 257         ts.tv_nsec = 1000000*(t%1000);
 258
 259         do {
 260                 errno = 0;
 261                 ret = nanosleep(&ts, &ts);
 262         } while (ret < 0 && errno == EINTR && (ts.tv_sec > 0 || ts.tv_nsec > 0));
 263 #else
 264         unsigned int tdiff=0;
 265         struct timeval tval,t1,t2;
 266         fd_set fds;
 267
 268         GetTimeOfDay(&t1);
 269         t2 = t1;
 270
 271         while (tdiff < t) {
 272                 tval.tv_sec = (t-tdiff)/1000;
 273                 tval.tv_usec = 1000*((t-tdiff)%1000);
 274
 275                 /* Never wait for more than 1 sec. */
 276                 if (tval.tv_sec > 1) {
 277                         tval.tv_sec = 1;
 278                         tval.tv_usec = 0;
 279                 }
 280
 281                 FD_ZERO(&fds);
 282                 errno = 0;
 283                 select(0,&fds,NULL,NULL,&tval);
 284
 285                 GetTimeOfDay(&t2);
 286                 if (t2.tv_sec < t1.tv_sec) {
 287                         /* Someone adjusted time... */
 288                         t1 = t2;
 289                 }
 290
 291                 tdiff = usec_time_diff(&t2,&t1)/1000;
 292         }
 293 #endif
 294 }
 295
 296 /**
 297  Get my own name, return in talloc'ed storage.
 298 **/
 299
 300 _PUBLIC_ char *get_myname(TALLOC_CTX *ctx)
 301 {
 302         char *p;
 303         char hostname[HOST_NAME_MAX];
 304
 305         /* get my host name */
 306         if (gethostname(hostname, sizeof(hostname)) == -1) {
 307                 DEBUG(0,("gethostname failed\n"));
 308                 return NULL;
 309         }
 310
 311         /* Ensure null termination. */
 312         hostname[sizeof(hostname)-1] = '\0';
 313
 314         /* split off any parts after an initial . */
 315         p = strchr_m(hostname, '.');
 316         if (p) {
 317                 *p = 0;
 318         }
 319
 320         return talloc_strdup(ctx, hostname);
 321 }
 322
 323 /**
 324  Check if a process exists. Does this work on all unixes?
 325 **/
 326
 327 _PUBLIC_ bool process_exists_by_pid(pid_t pid)
 328 {
 329         /* Doing kill with a non-positive pid causes messages to be
 330          * sent to places we don't want. */
 331         if (pid <= 0) {
 332                 return false;
 333         }
 334         return(kill(pid,0) == 0 || errno != ESRCH);
 335 }
 336
 337 /**
 338  Simple routine to do POSIX file locking. Cruft in NFS and 64->32 bit mapping
 339  is dealt with in posix.c
 340 **/
 341
 342 _PUBLIC_ bool fcntl_lock(int fd, int op, off_t offset, off_t count, int type)
 343 {
 344         struct flock lock;
 345         int ret;
 346
 347         DEBUG(8,("fcntl_lock %d %d %.0f %.0f %d\n",fd,op,(double)offset,(double)count,type));
 348
 349         lock.l_type = type;
 350         lock.l_whence = SEEK_SET;
 351         lock.l_start = offset;
 352         lock.l_len = count;
 353         lock.l_pid = 0;
 354
 355         ret = fcntl(fd,op,&lock);
 356
 357         if (ret == -1 && errno != 0)
 358                 DEBUG(3,("fcntl_lock: fcntl lock gave errno %d (%s)\n",errno,strerror(errno)));
 359
 360         /* a lock query */
 361         if (op == F_GETLK) {
 362                 if ((ret != -1) &&
 363                                 (lock.l_type != F_UNLCK) &&
 364                                 (lock.l_pid != 0) &&
 365                                 (lock.l_pid != getpid())) {
 366                         DEBUG(3,("fcntl_lock: fd %d is locked by pid %d\n",fd,(int)lock.l_pid));
 367                         return true;
 368                 }
 369
 370                 /* it must be not locked or locked by me */
 371                 return false;
 372         }
 373
 374         /* a lock set or unset */
 375         if (ret == -1) {
 376                 DEBUG(3,("fcntl_lock: lock failed at offset %.0f count %.0f op %d type %d (%s)\n",
 377                         (double)offset,(double)count,op,type,strerror(errno)));
 378                 return false;
 379         }
 380
 381         /* everything went OK */
 382         DEBUG(8,("fcntl_lock: Lock call successful\n"));
 383
 384         return true;
 385 }
 386
 387 struct debug_channel_level {
 388         int channel;
 389         int level;
 390 };
 391
 392 static void debugadd_channel_cb(const char *buf, void *private_data)
 393 {
 394         struct debug_channel_level *dcl =
 395                 (struct debug_channel_level *)private_data;
 396
 397         DEBUGADDC(dcl->channel, dcl->level,("%s", buf));
 398 }
 399
 400 static void debugadd_cb(const char *buf, void *private_data)
 401 {
 402         int *plevel = (int *)private_data;
 403         DEBUGADD(*plevel, ("%s", buf));
 404 }
 405
 406 void print_asc_cb(const uint8_t *buf, int len,
 407                   void (*cb)(const char *buf, void *private_data),
 408                   void *private_data)
 409 {
 410         int i;
 411         char s[2];
 412         s[1] = 0;
 413
 414         for (i=0; i<len; i++) {
 415                 s[0] = isprint(buf[i]) ? buf[i] : '.';
 416                 cb(s, private_data);
 417         }
 418 }
 419
 420 void print_asc(int level, const uint8_t *buf,int len)
 421 {
 422         print_asc_cb(buf, len, debugadd_cb, &level);
 423 }
 424
 425 /**
 426  * Write dump of binary data to a callback
 427  */
 428 void dump_data_cb(const uint8_t *buf, int len,
 429                   bool omit_zero_bytes,
 430                   void (*cb)(const char *buf, void *private_data),
 431                   void *private_data)
 432 {
 433         int i=0;
 434         static const uint8_t empty[16] = { 0, };
 435         bool skipped = false;
 436         char tmp[16];
 437
 438         if (len<=0) return;
 439
 440         for (i=0;i<len;) {
 441
 442                 if (i%16 == 0) {
 443                         if ((omit_zero_bytes == true) &&
 444                             (i > 0) &&
 445                             (len > i+16) &&
 446                             (memcmp(&buf[i], &empty, 16) == 0))
 447                         {
 448                                 i +=16;
 449                                 continue;
 450                         }
 451
 452                         if (i<len)  {
 453                                 snprintf(tmp, sizeof(tmp), "[%04X] ", i);
 454                                 cb(tmp, private_data);
 455                         }
 456                 }
 457
 458                 snprintf(tmp, sizeof(tmp), "%02X ", (int)buf[i]);
 459                 cb(tmp, private_data);
 460                 i++;
 461                 if (i%8 == 0) {
 462                         cb("  ", private_data);
 463                 }
 464                 if (i%16 == 0) {
 465
 466                         print_asc_cb(&buf[i-16], 8, cb, private_data);
 467                         cb(" ", private_data);
 468                         print_asc_cb(&buf[i-8], 8, cb, private_data);
 469                         cb("\n", private_data);
 470
 471                         if ((omit_zero_bytes == true) &&
 472                             (len > i+16) &&
 473                             (memcmp(&buf[i], &empty, 16) == 0)) {
 474                                 if (!skipped) {
 475                                         cb("skipping zero buffer bytes\n",
 476                                            private_data);
 477                                         skipped = true;
 478                                 }
 479                         }
 480                 }
 481         }
 482
 483         if (i%16) {
 484                 int n;
 485                 n = 16 - (i%16);
 486                 cb(" ", private_data);
 487                 if (n>8) {
 488                         cb(" ", private_data);
 489                 }
 490                 while (n--) {
 491                         cb("   ", private_data);
 492                 }
 493                 n = MIN(8,i%16);
 494                 print_asc_cb(&buf[i-(i%16)], n, cb, private_data);
 495                 cb(" ", private_data);
 496                 n = (i%16) - n;
 497                 if (n>0) {
 498                         print_asc_cb(&buf[i-n], n, cb, private_data);
 499                 }
 500                 cb("\n", private_data);
 501         }
 502
 503 }
 504
 505 /**
 506  * Write dump of binary data to the log file.
 507  *
 508  * The data is only written if the log level is at least level.
 509  */
 510 _PUBLIC_ void dump_data(int level, const uint8_t *buf, int len)
 511 {
 512         if (!DEBUGLVL(level)) {
 513                 return;
 514         }
 515         dump_data_cb(buf, len, false, debugadd_cb, &level);
 516 }
 517
 518 /**
 519  * Write dump of binary data to the log file.
 520  *
 521  * The data is only written if the log level is at least level for
 522  * debug class dbgc_class.
 523  */
 524 _PUBLIC_ void dump_data_dbgc(int dbgc_class, int level, const uint8_t *buf, int len)
 525 {
 526         struct debug_channel_level dcl = { dbgc_class, level };
 527
 528         if (!DEBUGLVLC(dbgc_class, level)) {
 529                 DEBUG(0, ("dbgc_class is %d\n", dbgc_class));
 530                 return;
 531         }
 532         dump_data_cb(buf, len, false, debugadd_channel_cb, &dcl);
 533 }
 534
 535 /**
 536  * Write dump of binary data to the log file.
 537  *
 538  * The data is only written if the log level is at least level.
 539  * 16 zero bytes in a row are omitted
 540  */
 541 _PUBLIC_ void dump_data_skip_zeros(int level, const uint8_t *buf, int len)
 542 {
 543         if (!DEBUGLVL(level)) {
 544                 return;
 545         }
 546         dump_data_cb(buf, len, true, debugadd_cb, &level);
 547 }
 548
 549 static void fprintf_cb(const char *buf, void *private_data)
 550 {
 551         FILE *f = (FILE *)private_data;
 552         fprintf(f, "%s", buf);
 553 }
 554
 555 void dump_data_file(const uint8_t *buf, int len, bool omit_zero_bytes,
 556                     FILE *f)
 557 {
 558         dump_data_cb(buf, len, omit_zero_bytes, fprintf_cb, f);
 559 }
 560
 561 /**
 562  malloc that aborts with smb_panic on fail or zero size.
 563 **/
 564
 565 _PUBLIC_ void *smb_xmalloc(size_t size)
 566 {
 567         void *p;
 568         if (size == 0)
 569                 smb_panic("smb_xmalloc: called with zero size.\n");
 570         if ((p = malloc(size)) == NULL)
 571                 smb_panic("smb_xmalloc: malloc fail.\n");
 572         return p;
 573 }
 574
 575 /**
 576  Memdup with smb_panic on fail.
 577 **/
 578
 579 _PUBLIC_ void *smb_xmemdup(const void *p, size_t size)
 580 {
 581         void *p2;
 582         p2 = smb_xmalloc(size);
 583         memcpy(p2, p, size);
 584         return p2;
 585 }
 586
 587 /**
 588  strdup that aborts on malloc fail.
 589 **/
 590
 591 char *smb_xstrdup(const char *s)
 592 {
 593 #if defined(PARANOID_MALLOC_CHECKER)
 594 #ifdef strdup
 595 #undef strdup
 596 #endif
 597 #endif
 598
 599 #ifndef HAVE_STRDUP
 600 #define strdup rep_strdup
 601 #endif
 602
 603         char *s1 = strdup(s);
 604 #if defined(PARANOID_MALLOC_CHECKER)
 605 #ifdef strdup
 606 #undef strdup
 607 #endif
 608 #define strdup(s) __ERROR_DONT_USE_STRDUP_DIRECTLY
 609 #endif
 610         if (!s1) {
 611                 smb_panic("smb_xstrdup: malloc failed");
 612         }
 613         return s1;
 614
 615 }
 616
 617 /**
 618  strndup that aborts on malloc fail.
 619 **/
 620
 621 char *smb_xstrndup(const char *s, size_t n)
 622 {
 623 #if defined(PARANOID_MALLOC_CHECKER)
 624 #ifdef strndup
 625 #undef strndup
 626 #endif
 627 #endif
 628
 629 #if (defined(BROKEN_STRNDUP) || !defined(HAVE_STRNDUP))
 630 #undef HAVE_STRNDUP
 631 #define strndup rep_strndup
 632 #endif
 633
 634         char *s1 = strndup(s, n);
 635 #if defined(PARANOID_MALLOC_CHECKER)
 636 #ifdef strndup
 637 #undef strndup
 638 #endif
 639 #define strndup(s,n) __ERROR_DONT_USE_STRNDUP_DIRECTLY
 640 #endif
 641         if (!s1) {
 642                 smb_panic("smb_xstrndup: malloc failed");
 643         }
 644         return s1;
 645 }
 646
 647
 648
 649 /**
 650  Like strdup but for memory.
 651 **/
 652
 653 _PUBLIC_ void *memdup(const void *p, size_t size)
 654 {
 655         void *p2;
 656         if (size == 0)
 657                 return NULL;
 658         p2 = malloc(size);
 659         if (!p2)
 660                 return NULL;
 661         memcpy(p2, p, size);
 662         return p2;
 663 }
 664
 665 /**
 666  * Write a password to the log file.
 667  *
 668  * @note Only actually does something if DEBUG_PASSWORD was defined during
 669  * compile-time.
 670  */
 671 _PUBLIC_ void dump_data_pw(const char *msg, const uint8_t * data, size_t len)
 672 {
 673 #ifdef DEBUG_PASSWORD
 674         DEBUG(11, ("%s", msg));
 675         if (data != NULL && len > 0)
 676         {
 677                 dump_data(11, data, len);
 678         }
 679 #endif
 680 }
 681
 682
 683 /**
 684  * see if a range of memory is all zero. A NULL pointer is considered
 685  * to be all zero
 686  */
 687 _PUBLIC_ bool all_zero(const uint8_t *ptr, size_t size)
 688 {
 689         int i;
 690         if (!ptr) return true;
 691         for (i=0;i<size;i++) {
 692                 if (ptr[i]) return false;
 693         }
 694         return true;
 695 }
 696
 697 /**
 698   realloc an array, checking for integer overflow in the array size
 699 */
 700 _PUBLIC_ void *realloc_array(void *ptr, size_t el_size, unsigned count, bool free_on_fail)
 701 {
 702 #define MAX_MALLOC_SIZE 0x7fffffff
 703         if (count == 0 ||
 704             count >= MAX_MALLOC_SIZE/el_size) {
 705                 if (free_on_fail)
 706                         SAFE_FREE(ptr);
 707                 return NULL;
 708         }
 709         if (!ptr) {
 710                 return malloc(el_size * count);
 711         }
 712         return realloc(ptr, el_size * count);
 713 }
 714
 715 /****************************************************************************
 716  Type-safe malloc.
 717 ****************************************************************************/
 718
 719 void *malloc_array(size_t el_size, unsigned int count)
 720 {
 721         return realloc_array(NULL, el_size, count, false);
 722 }
 723
 724 /****************************************************************************
 725  Type-safe memalign
 726 ****************************************************************************/
 727
 728 void *memalign_array(size_t el_size, size_t align, unsigned int count)
 729 {
 730         if (count*el_size >= MAX_MALLOC_SIZE) {
 731                 return NULL;
 732         }
 733
 734         return memalign(align, el_size*count);
 735 }
 736
 737 /****************************************************************************
 738  Type-safe calloc.
 739 ****************************************************************************/
 740
 741 void *calloc_array(size_t size, size_t nmemb)
 742 {
 743         if (nmemb >= MAX_MALLOC_SIZE/size) {
 744                 return NULL;
 745         }
 746         if (size == 0 || nmemb == 0) {
 747                 return NULL;
 748         }
 749         return calloc(nmemb, size);
 750 }
 751
 752 /**
 753  Trim the specified elements off the front and back of a string.
 754 **/
 755 _PUBLIC_ bool trim_string(char *s, const char *front, const char *back)
 756 {
 757         bool ret = false;
 758         size_t front_len;
 759         size_t back_len;
 760         size_t len;
 761
 762         /* Ignore null or empty strings. */
 763         if (!s || (s[0] == '\0'))
 764                 return false;
 765
 766         front_len       = front? strlen(front) : 0;
 767         back_len        = back? strlen(back) : 0;
 768
 769         len = strlen(s);
 770
 771         if (front_len) {
 772                 while (len && strncmp(s, front, front_len)==0) {
 773                         /* Must use memmove here as src & dest can
 774                          * easily overlap. Found by valgrind. JRA. */
 775                         memmove(s, s+front_len, (len-front_len)+1);
 776                         len -= front_len;
 777                         ret=true;
 778                 }
 779         }
 780
 781         if (back_len) {
 782                 while ((len >= back_len) && strncmp(s+len-back_len,back,back_len)==0) {
 783                         s[len-back_len]='\0';
 784                         len -= back_len;
 785                         ret=true;
 786                 }
 787         }
 788         return ret;
 789 }
 790
 791 /**
 792  Find the number of 'c' chars in a string
 793 **/
 794 _PUBLIC_ _PURE_ size_t count_chars(const char *s, char c)
 795 {
 796         size_t count = 0;
 797
 798         while (*s) {
 799                 if (*s == c) count++;
 800                 s ++;
 801         }
 802
 803         return count;
 804 }
 805
 806 /**
 807  * Routine to get hex characters and turn them into a byte array.
 808  * the array can be variable length.
 809  * -  "0xnn" or "0Xnn" is specially catered for.
 810  * - The first non-hex-digit character (apart from possibly leading "0x"
 811  *   finishes the conversion and skips the rest of the input.
 812  * - A single hex-digit character at the end of the string is skipped.
 813  *
 814  * valid examples: "0A5D15"; "0x123456"
 815  */
 816 _PUBLIC_ size_t strhex_to_str(char *p, size_t p_len, const char *strhex, size_t strhex_len)
 817 {
 818         size_t i = 0;
 819         size_t num_chars = 0;
 820         uint8_t   lonybble, hinybble;
 821         const char     *hexchars = "0123456789ABCDEF";
 822         char           *p1 = NULL, *p2 = NULL;
 823
 824         /* skip leading 0x prefix */
 825         if (strncasecmp(strhex, "0x", 2) == 0) {
 826                 i += 2; /* skip two chars */
 827         }
 828
 829         for (; i+1 < strhex_len && strhex[i] != 0 && strhex[i+1] != 0; i++) {
 830                 p1 = strchr(hexchars, toupper((unsigned char)strhex[i]));
 831                 if (p1 == NULL) {
 832                         break;
 833                 }
 834
 835                 i++; /* next hex digit */
 836
 837                 p2 = strchr(hexchars, toupper((unsigned char)strhex[i]));
 838                 if (p2 == NULL) {
 839                         break;
 840                 }
 841
 842                 /* get the two nybbles */
 843                 hinybble = PTR_DIFF(p1, hexchars);
 844                 lonybble = PTR_DIFF(p2, hexchars);
 845
 846                 if (num_chars >= p_len) {
 847                         break;
 848                 }
 849
 850                 p[num_chars] = (hinybble << 4) | lonybble;
 851                 num_chars++;
 852
 853                 p1 = NULL;
 854                 p2 = NULL;
 855         }
 856         return num_chars;
 857 }
 858
 859 /**
 860  * Parse a hex string and return a data blob.
 861  */
 862 _PUBLIC_ _PURE_ DATA_BLOB strhex_to_data_blob(TALLOC_CTX *mem_ctx, const char *strhex)
 863 {
 864         DATA_BLOB ret_blob = data_blob_talloc(mem_ctx, NULL, strlen(strhex)/2+1);
 865
 866         ret_blob.length = strhex_to_str((char *)ret_blob.data, ret_blob.length,
 867                                         strhex,
 868                                         strlen(strhex));
 869
 870         return ret_blob;
 871 }
 872
 873 /**
 874  * Print a buf in hex. Assumes dst is at least (srclen*2)+1 large.
 875  */
 876 _PUBLIC_ void hex_encode_buf(char *dst, const uint8_t *src, size_t srclen)
 877 {
 878         size_t i;
 879         for (i=0; i<srclen; i++) {
 880                 snprintf(dst + i*2, 3, "%02X", src[i]);
 881         }
 882         /*
 883          * Ensure 0-termination for 0-length buffers
 884          */
 885         dst[srclen*2] = '\0';
 886 }
 887
 888 /**
 889  * Routine to print a buffer as HEX digits, into an allocated string.
 890  */
 891 _PUBLIC_ void hex_encode(const unsigned char *buff_in, size_t len, char **out_hex_buffer)
 892 {
 893         char *hex_buffer;
 894
 895         *out_hex_buffer = malloc_array_p(char, (len*2)+1);
 896         hex_buffer = *out_hex_buffer;
 897         hex_encode_buf(hex_buffer, buff_in, len);
 898 }
 899
 900 /**
 901  * talloc version of hex_encode()
 902  */
 903 _PUBLIC_ char *hex_encode_talloc(TALLOC_CTX *mem_ctx, const unsigned char *buff_in, size_t len)
 904 {
 905         char *hex_buffer;
 906
 907         hex_buffer = talloc_array(mem_ctx, char, (len*2)+1);
 908         if (!hex_buffer) {
 909                 return NULL;
 910         }
 911         hex_encode_buf(hex_buffer, buff_in, len);
 912         talloc_set_name_const(hex_buffer, hex_buffer);
 913         return hex_buffer;
 914 }
 915
 916 /**
 917   varient of strcmp() that handles NULL ptrs
 918 **/
 919 _PUBLIC_ int strcmp_safe(const char *s1, const char *s2)
 920 {
 921         if (s1 == s2) {
 922                 return 0;
 923         }
 924         if (s1 == NULL || s2 == NULL) {
 925                 return s1?-1:1;
 926         }
 927         return strcmp(s1, s2);
 928 }
 929
 930
 931 /**
 932 return the number of bytes occupied by a buffer in ASCII format
 933 the result includes the null termination
 934 limited by 'n' bytes
 935 **/
 936 _PUBLIC_ size_t ascii_len_n(const char *src, size_t n)
 937 {
 938         size_t len;
 939
 940         len = strnlen(src, n);
 941         if (len+1 <= n) {
 942                 len += 1;
 943         }
 944
 945         return len;
 946 }
 947
 948 /**
 949  Set a boolean variable from the text value stored in the passed string.
 950  Returns true in success, false if the passed string does not correctly
 951  represent a boolean.
 952 **/
 953
 954 _PUBLIC_ bool set_boolean(const char *boolean_string, bool *boolean)
 955 {
 956         if (strwicmp(boolean_string, "yes") == 0 ||
 957             strwicmp(boolean_string, "true") == 0 ||
 958             strwicmp(boolean_string, "on") == 0 ||
 959             strwicmp(boolean_string, "1") == 0) {
 960                 *boolean = true;
 961                 return true;
 962         } else if (strwicmp(boolean_string, "no") == 0 ||
 963                    strwicmp(boolean_string, "false") == 0 ||
 964                    strwicmp(boolean_string, "off") == 0 ||
 965                    strwicmp(boolean_string, "0") == 0) {
 966                 *boolean = false;
 967                 return true;
 968         }
 969         return false;
 970 }
 971
 972 /**
 973 return the number of bytes occupied by a buffer in CH_UTF16 format
 974 the result includes the null termination
 975 **/
 976 _PUBLIC_ size_t utf16_len(const void *buf)
 977 {
 978         size_t len;
 979
 980         for (len = 0; SVAL(buf,len); len += 2) ;
 981
 982         return len + 2;
 983 }
 984
 985 /**
 986 return the number of bytes occupied by a buffer in CH_UTF16 format
 987 the result includes the null termination
 988 limited by 'n' bytes
 989 **/
 990 _PUBLIC_ size_t utf16_len_n(const void *src, size_t n)
 991 {
 992         size_t len;
 993
 994         for (len = 0; (len+2 < n) && SVAL(src, len); len += 2) ;
 995
 996         if (len+2 <= n) {
 997                 len += 2;
 998         }
 999
1000         return len;
1001 }
1002
1003 /**
1004  * @file
1005  * @brief String utilities.
1006  **/
1007
1008 static bool next_token_internal_talloc(TALLOC_CTX *ctx,
1009                                 const char **ptr,
1010                                 char **pp_buff,
1011                                 const char *sep,
1012                                 bool ltrim)
1013 {
1014         const char *s;
1015         const char *saved_s;
1016         char *pbuf;
1017         bool quoted;
1018         size_t len=1;
1019
1020         *pp_buff = NULL;
1021         if (!ptr) {
1022                 return(false);
1023         }
1024
1025         s = *ptr;
1026
1027         /* default to simple separators */
1028         if (!sep) {
1029                 sep = " \t\n\r";
1030         }
1031
1032         /* find the first non sep char, if left-trimming is requested */
1033         if (ltrim) {
1034                 while (*s && strchr_m(sep,*s)) {
1035                         s++;
1036                 }
1037         }
1038
1039         /* nothing left? */
1040         if (!*s) {
1041                 return false;
1042         }
1043
1044         /* When restarting we need to go from here. */
1045         saved_s = s;
1046
1047         /* Work out the length needed. */
1048         for (quoted = false; *s &&
1049                         (quoted || !strchr_m(sep,*s)); s++) {
1050                 if (*s == '\"') {
1051                         quoted = !quoted;
1052                 } else {
1053                         len++;
1054                 }
1055         }
1056
1057         /* We started with len = 1 so we have space for the nul. */
1058         *pp_buff = talloc_array(ctx, char, len);
1059         if (!*pp_buff) {
1060                 return false;
1061         }
1062
1063         /* copy over the token */
1064         pbuf = *pp_buff;
1065         s = saved_s;
1066         for (quoted = false; *s &&
1067                         (quoted || !strchr_m(sep,*s)); s++) {
1068                 if ( *s == '\"' ) {
1069                         quoted = !quoted;
1070                 } else {
1071                         *pbuf++ = *s;
1072                 }
1073         }
1074
1075         *ptr = (*s) ? s+1 : s;
1076         *pbuf = 0;
1077
1078         return true;
1079 }
1080
1081 bool next_token_talloc(TALLOC_CTX *ctx,
1082                         const char **ptr,
1083                         char **pp_buff,
1084                         const char *sep)
1085 {
1086         return next_token_internal_talloc(ctx, ptr, pp_buff, sep, true);
1087 }
1088
1089 /*
1090  * Get the next token from a string, return false if none found.  Handles
1091  * double-quotes.  This version does not trim leading separator characters
1092  * before looking for a token.
1093  */
1094
1095 bool next_token_no_ltrim_talloc(TALLOC_CTX *ctx,
1096                         const char **ptr,
1097                         char **pp_buff,
1098                         const char *sep)
1099 {
1100         return next_token_internal_talloc(ctx, ptr, pp_buff, sep, false);
1101 }
1102
1103 /**
1104  * Get the next token from a string, return False if none found.
1105  * Handles double-quotes.
1106  *
1107  * Based on a routine by GJC@VILLAGE.COM.
1108  * Extensively modified by Andrew.Tridgell@anu.edu.au
1109  **/
1110 _PUBLIC_ bool next_token(const char **ptr,char *buff, const char *sep, size_t bufsize)
1111 {
1112         const char *s;
1113         bool quoted;
1114         size_t len=1;
1115
1116         if (!ptr)
1117                 return false;
1118
1119         s = *ptr;
1120
1121         /* default to simple separators */
1122         if (!sep)
1123                 sep = " \t\n\r";
1124
1125         /* find the first non sep char */
1126         while (*s && strchr_m(sep,*s))
1127                 s++;
1128
1129         /* nothing left? */
1130         if (!*s)
1131                 return false;
1132
1133         /* copy over the token */
1134         for (quoted = false; len < bufsize && *s && (quoted || !strchr_m(sep,*s)); s++) {
1135                 if (*s == '\"') {
1136                         quoted = !quoted;
1137                 } else {
1138                         len++;
1139                         *buff++ = *s;
1140                 }
1141         }
1142
1143         *ptr = (*s) ? s+1 : s;
1144         *buff = 0;
1145
1146         return true;
1147 }
1148
1149 struct anonymous_shared_header {
1150         union {
1151                 size_t length;
1152                 uint8_t pad[16];
1153         } u;
1154 };
1155
1156 /* Map a shared memory buffer of at least nelem counters. */
1157 void *anonymous_shared_allocate(size_t orig_bufsz)
1158 {
1159         void *ptr;
1160         void *buf;
1161         size_t pagesz = getpagesize();
1162         size_t pagecnt;
1163         size_t bufsz = orig_bufsz;
1164         struct anonymous_shared_header *hdr;
1165
1166         bufsz += sizeof(*hdr);
1167
1168         /* round up to full pages */
1169         pagecnt = bufsz / pagesz;
1170         if (bufsz % pagesz) {
1171                 pagecnt += 1;
1172         }
1173         bufsz = pagesz * pagecnt;
1174
1175         if (orig_bufsz >= bufsz) {
1176                 /* integer wrap */
1177                 errno = ENOMEM;
1178                 return NULL;
1179         }
1180
1181 #ifdef MAP_ANON
1182         /* BSD */
1183         buf = mmap(NULL, bufsz, PROT_READ|PROT_WRITE, MAP_ANON|MAP_SHARED,
1184                         -1 /* fd */, 0 /* offset */);
1185 #else
1186 {
1187         int saved_errno;
1188         int fd;
1189
1190         fd = open("/dev/zero", O_RDWR);
1191         if (fd == -1) {
1192                 return NULL;
1193         }
1194
1195         buf = mmap(NULL, bufsz, PROT_READ|PROT_WRITE, MAP_FILE|MAP_SHARED,
1196                    fd, 0 /* offset */);
1197         saved_errno = errno;
1198         close(fd);
1199         errno = saved_errno;
1200 }
1201 #endif
1202
1203         if (buf == MAP_FAILED) {
1204                 return NULL;
1205         }
1206
1207         hdr = (struct anonymous_shared_header *)buf;
1208         hdr->u.length = bufsz;
1209
1210         ptr = (void *)(&hdr[1]);
1211
1212         return ptr;
1213 }
1214
1215 void *anonymous_shared_resize(void *ptr, size_t new_size, bool maymove)
1216 {
1217 #ifdef HAVE_MREMAP
1218         void *buf;
1219         size_t pagesz = getpagesize();
1220         size_t pagecnt;
1221         size_t bufsz;
1222         struct anonymous_shared_header *hdr;
1223         int flags = 0;
1224
1225         if (ptr == NULL) {
1226                 errno = EINVAL;
1227                 return NULL;
1228         }
1229
1230         hdr = (struct anonymous_shared_header *)ptr;
1231         hdr--;
1232         if (hdr->u.length > (new_size + sizeof(*hdr))) {
1233                 errno = EINVAL;
1234                 return NULL;
1235         }
1236
1237         bufsz = new_size + sizeof(*hdr);
1238
1239         /* round up to full pages */
1240         pagecnt = bufsz / pagesz;
1241         if (bufsz % pagesz) {
1242                 pagecnt += 1;
1243         }
1244         bufsz = pagesz * pagecnt;
1245
1246         if (new_size >= bufsz) {
1247                 /* integer wrap */
1248                 errno = ENOSPC;
1249                 return NULL;
1250         }
1251
1252         if (bufsz <= hdr->u.length) {
1253                 return ptr;
1254         }
1255
1256         if (maymove) {
1257                 flags = MREMAP_MAYMOVE;
1258         }
1259
1260         buf = mremap(hdr, hdr->u.length, bufsz, flags);
1261
1262         if (buf == MAP_FAILED) {
1263                 errno = ENOSPC;
1264                 return NULL;
1265         }
1266
1267         hdr = (struct anonymous_shared_header *)buf;
1268         hdr->u.length = bufsz;
1269
1270         ptr = (void *)(&hdr[1]);
1271
1272         return ptr;
1273 #else
1274         errno = ENOSPC;
1275         return NULL;
1276 #endif
1277 }
1278
1279 void anonymous_shared_free(void *ptr)
1280 {
1281         struct anonymous_shared_header *hdr;
1282
1283         if (ptr == NULL) {
1284                 return;
1285         }
1286
1287         hdr = (struct anonymous_shared_header *)ptr;
1288
1289         hdr--;
1290
1291         munmap(hdr, hdr->u.length);
1292 }
1293
1294 #ifdef DEVELOPER
1295 /* used when you want a debugger started at a particular point in the
1296    code. Mostly useful in code that runs as a child process, where
1297    normal gdb attach is harder to organise.
1298 */
1299 void samba_start_debugger(void)
1300 {
1301         char *cmd = NULL;
1302         if (asprintf(&cmd, "xterm -e \"gdb --pid %u\"&", getpid()) == -1) {
1303                 return;
1304         }
1305         if (system(cmd) == -1) {
1306                 free(cmd);
1307                 return;
1308         }
1309         free(cmd);
1310         sleep(2);
1311 }
1312 #endif