lib/replace/replace.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    replacement routines for broken systems
   4    Copyright (C) Andrew Tridgell 1992-1998
   5    Copyright (C) Jelmer Vernooij 2005-2008
   6
   7      ** NOTE! The following LGPL license applies to the replace
   8      ** library. This does NOT imply that all of Samba is released
   9      ** under the LGPL
  10
  11    This library is free software; you can redistribute it and/or
  12    modify it under the terms of the GNU Lesser General Public
  13    License as published by the Free Software Foundation; either
  14    version 3 of the License, or (at your option) any later version.
  15
  16    This library 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 GNU
  19    Lesser General Public License for more details.
  20
  21    You should have received a copy of the GNU Lesser General Public
  22    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "replace.h"
  26
  27 #include "system/filesys.h"
  28 #include "system/time.h"
  29 #include "system/passwd.h"
  30 #include "system/syslog.h"
  31 #include "system/locale.h"
  32 #include "system/wait.h"
  33
  34 #ifdef _WIN32
  35 #define mkdir(d,m) _mkdir(d)
  36 #endif
  37
  38 void replace_dummy(void);
  39 void replace_dummy(void) {}
  40
  41 #ifndef HAVE_FTRUNCATE
  42  /*******************************************************************
  43 ftruncate for operating systems that don't have it
  44 ********************************************************************/
  45 int rep_ftruncate(int f, off_t l)
  46 {
  47 #ifdef HAVE_CHSIZE
  48       return chsize(f,l);
  49 #elif defined(F_FREESP)
  50       struct  flock   fl;
  51
  52       fl.l_whence = 0;
  53       fl.l_len = 0;
  54       fl.l_start = l;
  55       fl.l_type = F_WRLCK;
  56       return fcntl(f, F_FREESP, &fl);
  57 #else
  58 #error "you must have a ftruncate function"
  59 #endif
  60 }
  61 #endif /* HAVE_FTRUNCATE */
  62
  63
  64 #ifndef HAVE_STRLCPY
  65 /* like strncpy but does not 0 fill the buffer and always null
  66    terminates. bufsize is the size of the destination buffer */
  67 size_t rep_strlcpy(char *d, const char *s, size_t bufsize)
  68 {
  69         size_t len = strlen(s);
  70         size_t ret = len;
  71         if (bufsize <= 0) return 0;
  72         if (len >= bufsize) len = bufsize-1;
  73         memcpy(d, s, len);
  74         d[len] = 0;
  75         return ret;
  76 }
  77 #endif
  78
  79 #ifndef HAVE_STRLCAT
  80 /* like strncat but does not 0 fill the buffer and always null
  81    terminates. bufsize is the length of the buffer, which should
  82    be one more than the maximum resulting string length */
  83 size_t rep_strlcat(char *d, const char *s, size_t bufsize)
  84 {
  85         size_t len1 = strlen(d);
  86         size_t len2 = strlen(s);
  87         size_t ret = len1 + len2;
  88
  89         if (len1+len2 >= bufsize) {
  90                 if (bufsize < (len1+1)) {
  91                         return ret;
  92                 }
  93                 len2 = bufsize - (len1+1);
  94         }
  95         if (len2 > 0) {
  96                 memcpy(d+len1, s, len2);
  97                 d[len1+len2] = 0;
  98         }
  99         return ret;
 100 }
 101 #endif
 102
 103 #ifndef HAVE_MKTIME
 104 /*******************************************************************
 105 a mktime() replacement for those who don't have it - contributed by
 106 C.A. Lademann <cal@zls.com>
 107 Corrections by richard.kettlewell@kewill.com
 108 ********************************************************************/
 109
 110 #define  MINUTE  60
 111 #define  HOUR    60*MINUTE
 112 #define  DAY             24*HOUR
 113 #define  YEAR    365*DAY
 114 time_t rep_mktime(struct tm *t)
 115 {
 116   struct tm       *u;
 117   time_t  epoch = 0;
 118   int n;
 119   int             mon [] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
 120   y, m, i;
 121
 122   if(t->tm_year < 70)
 123     return((time_t)-1);
 124
 125   n = t->tm_year + 1900 - 1;
 126   epoch = (t->tm_year - 70) * YEAR +
 127     ((n / 4 - n / 100 + n / 400) - (1969 / 4 - 1969 / 100 + 1969 / 400)) * DAY;
 128
 129   y = t->tm_year + 1900;
 130   m = 0;
 131
 132   for(i = 0; i < t->tm_mon; i++) {
 133     epoch += mon [m] * DAY;
 134     if(m == 1 && y % 4 == 0 && (y % 100 != 0 || y % 400 == 0))
 135       epoch += DAY;
 136
 137     if(++m > 11) {
 138       m = 0;
 139       y++;
 140     }
 141   }
 142
 143   epoch += (t->tm_mday - 1) * DAY;
 144   epoch += t->tm_hour * HOUR + t->tm_min * MINUTE + t->tm_sec;
 145
 146   if((u = localtime(&epoch)) != NULL) {
 147     t->tm_sec = u->tm_sec;
 148     t->tm_min = u->tm_min;
 149     t->tm_hour = u->tm_hour;
 150     t->tm_mday = u->tm_mday;
 151     t->tm_mon = u->tm_mon;
 152     t->tm_year = u->tm_year;
 153     t->tm_wday = u->tm_wday;
 154     t->tm_yday = u->tm_yday;
 155     t->tm_isdst = u->tm_isdst;
 156   }
 157
 158   return(epoch);
 159 }
 160 #endif /* !HAVE_MKTIME */
 161
 162
 163 #ifndef HAVE_INITGROUPS
 164 /****************************************************************************
 165  some systems don't have an initgroups call
 166 ****************************************************************************/
 167 int rep_initgroups(char *name, gid_t id)
 168 {
 169 #ifndef HAVE_SETGROUPS
 170         /* yikes! no SETGROUPS or INITGROUPS? how can this work? */
 171         errno = ENOSYS;
 172         return -1;
 173 #else /* HAVE_SETGROUPS */
 174
 175 #include <grp.h>
 176
 177         gid_t *grouplst = NULL;
 178         int max_gr = NGROUPS_MAX;
 179         int ret;
 180         int    i,j;
 181         struct group *g;
 182         char   *gr;
 183
 184         if((grouplst = malloc(sizeof(gid_t) * max_gr)) == NULL) {
 185                 errno = ENOMEM;
 186                 return -1;
 187         }
 188
 189         grouplst[0] = id;
 190         i = 1;
 191         while (i < max_gr && ((g = (struct group *)getgrent()) != (struct group *)NULL)) {
 192                 if (g->gr_gid == id)
 193                         continue;
 194                 j = 0;
 195                 gr = g->gr_mem[0];
 196                 while (gr && (*gr != (char)NULL)) {
 197                         if (strcmp(name,gr) == 0) {
 198                                 grouplst[i] = g->gr_gid;
 199                                 i++;
 200                                 gr = (char *)NULL;
 201                                 break;
 202                         }
 203                         gr = g->gr_mem[++j];
 204                 }
 205         }
 206         endgrent();
 207         ret = setgroups(i, grouplst);
 208         free(grouplst);
 209         return ret;
 210 #endif /* HAVE_SETGROUPS */
 211 }
 212 #endif /* HAVE_INITGROUPS */
 213
 214
 215 #if (defined(SecureWare) && defined(SCO))
 216 /* This is needed due to needing the nap() function but we don't want
 217    to include the Xenix libraries since that will break other things...
 218    BTW: system call # 0x0c28 is the same as calling nap() */
 219 long nap(long milliseconds) {
 220          return syscall(0x0c28, milliseconds);
 221  }
 222 #endif
 223
 224
 225 #ifndef HAVE_MEMMOVE
 226 /*******************************************************************
 227 safely copies memory, ensuring no overlap problems.
 228 this is only used if the machine does not have its own memmove().
 229 this is not the fastest algorithm in town, but it will do for our
 230 needs.
 231 ********************************************************************/
 232 void *rep_memmove(void *dest,const void *src,int size)
 233 {
 234         unsigned long d,s;
 235         int i;
 236         if (dest==src || !size) return(dest);
 237
 238         d = (unsigned long)dest;
 239         s = (unsigned long)src;
 240
 241         if ((d >= (s+size)) || (s >= (d+size))) {
 242                 /* no overlap */
 243                 memcpy(dest,src,size);
 244                 return(dest);
 245         }
 246
 247         if (d < s) {
 248                 /* we can forward copy */
 249                 if (s-d >= sizeof(int) &&
 250                     !(s%sizeof(int)) &&
 251                     !(d%sizeof(int)) &&
 252                     !(size%sizeof(int))) {
 253                         /* do it all as words */
 254                         int *idest = (int *)dest;
 255                         int *isrc = (int *)src;
 256                         size /= sizeof(int);
 257                         for (i=0;i<size;i++) idest[i] = isrc[i];
 258                 } else {
 259                         /* simplest */
 260                         char *cdest = (char *)dest;
 261                         char *csrc = (char *)src;
 262                         for (i=0;i<size;i++) cdest[i] = csrc[i];
 263                 }
 264         } else {
 265                 /* must backward copy */
 266                 if (d-s >= sizeof(int) &&
 267                     !(s%sizeof(int)) &&
 268                     !(d%sizeof(int)) &&
 269                     !(size%sizeof(int))) {
 270                         /* do it all as words */
 271                         int *idest = (int *)dest;
 272                         int *isrc = (int *)src;
 273                         size /= sizeof(int);
 274                         for (i=size-1;i>=0;i--) idest[i] = isrc[i];
 275                 } else {
 276                         /* simplest */
 277                         char *cdest = (char *)dest;
 278                         char *csrc = (char *)src;
 279                         for (i=size-1;i>=0;i--) cdest[i] = csrc[i];
 280                 }
 281         }
 282         return(dest);
 283 }
 284 #endif /* HAVE_MEMMOVE */
 285
 286 #ifndef HAVE_STRDUP
 287 /****************************************************************************
 288 duplicate a string
 289 ****************************************************************************/
 290 char *rep_strdup(const char *s)
 291 {
 292         size_t len;
 293         char *ret;
 294
 295         if (!s) return(NULL);
 296
 297         len = strlen(s)+1;
 298         ret = (char *)malloc(len);
 299         if (!ret) return(NULL);
 300         memcpy(ret,s,len);
 301         return(ret);
 302 }
 303 #endif /* HAVE_STRDUP */
 304
 305 #ifndef HAVE_SETLINEBUF
 306 void rep_setlinebuf(FILE *stream)
 307 {
 308         setvbuf(stream, (char *)NULL, _IOLBF, 0);
 309 }
 310 #endif /* HAVE_SETLINEBUF */
 311
 312 #ifndef HAVE_VSYSLOG
 313 #ifdef HAVE_SYSLOG
 314 void rep_vsyslog (int facility_priority, const char *format, va_list arglist)
 315 {
 316         char *msg = NULL;
 317         vasprintf(&msg, format, arglist);
 318         if (!msg)
 319                 return;
 320         syslog(facility_priority, "%s", msg);
 321         free(msg);
 322 }
 323 #endif /* HAVE_SYSLOG */
 324 #endif /* HAVE_VSYSLOG */
 325
 326 #ifndef HAVE_STRNLEN
 327 /**
 328  Some platforms don't have strnlen
 329 **/
 330  size_t rep_strnlen(const char *s, size_t max)
 331 {
 332         size_t len;
 333
 334         for (len = 0; len < max; len++) {
 335                 if (s[len] == '\0') {
 336                         break;
 337                 }
 338         }
 339         return len;
 340 }
 341 #endif
 342
 343 #ifndef HAVE_STRNDUP
 344 /**
 345  Some platforms don't have strndup.
 346 **/
 347 char *rep_strndup(const char *s, size_t n)
 348 {
 349         char *ret;
 350
 351         n = strnlen(s, n);
 352         ret = malloc(n+1);
 353         if (!ret)
 354                 return NULL;
 355         memcpy(ret, s, n);
 356         ret[n] = 0;
 357
 358         return ret;
 359 }
 360 #endif
 361
 362 #if !defined(HAVE_WAITPID) && defined(HAVE_WAIT4)
 363 int rep_waitpid(pid_t pid,int *status,int options)
 364 {
 365   return wait4(pid, status, options, NULL);
 366 }
 367 #endif
 368
 369 #ifndef HAVE_SETEUID
 370 int rep_seteuid(uid_t euid)
 371 {
 372 #ifdef HAVE_SETRESUID
 373         return setresuid(-1, euid, -1);
 374 #else
 375         errno = ENOSYS;
 376         return -1;
 377 #endif
 378 }
 379 #endif
 380
 381 #ifndef HAVE_SETEGID
 382 int rep_setegid(gid_t egid)
 383 {
 384 #ifdef HAVE_SETRESGID
 385         return setresgid(-1, egid, -1);
 386 #else
 387         errno = ENOSYS;
 388         return -1;
 389 #endif
 390 }
 391 #endif
 392
 393 /*******************************************************************
 394 os/2 also doesn't have chroot
 395 ********************************************************************/
 396 #ifndef HAVE_CHROOT
 397 int rep_chroot(const char *dname)
 398 {
 399         errno = ENOSYS;
 400         return -1;
 401 }
 402 #endif
 403
 404 /*****************************************************************
 405  Possibly replace mkstemp if it is broken.
 406 *****************************************************************/
 407
 408 #ifndef HAVE_SECURE_MKSTEMP
 409 int rep_mkstemp(char *template)
 410 {
 411         /* have a reasonable go at emulating it. Hope that
 412            the system mktemp() isn't completly hopeless */
 413         char *p = mktemp(template);
 414         if (!p)
 415                 return -1;
 416         return open(p, O_CREAT|O_EXCL|O_RDWR, 0600);
 417 }
 418 #endif
 419
 420 #ifndef HAVE_MKDTEMP
 421 char *rep_mkdtemp(char *template)
 422 {
 423         char *dname;
 424
 425         if ((dname = mktemp(template))) {
 426                 if (mkdir(dname, 0700) >= 0) {
 427                         return dname;
 428                 }
 429         }
 430
 431         return NULL;
 432 }
 433 #endif
 434
 435 /*****************************************************************
 436  Watch out: this is not thread safe.
 437 *****************************************************************/
 438
 439 #ifndef HAVE_PREAD
 440 ssize_t rep_pread(int __fd, void *__buf, size_t __nbytes, off_t __offset)
 441 {
 442         if (lseek(__fd, __offset, SEEK_SET) != __offset) {
 443                 return -1;
 444         }
 445         return read(__fd, __buf, __nbytes);
 446 }
 447 #endif
 448
 449 /*****************************************************************
 450  Watch out: this is not thread safe.
 451 *****************************************************************/
 452
 453 #ifndef HAVE_PWRITE
 454 ssize_t rep_pwrite(int __fd, const void *__buf, size_t __nbytes, off_t __offset)
 455 {
 456         if (lseek(__fd, __offset, SEEK_SET) != __offset) {
 457                 return -1;
 458         }
 459         return write(__fd, __buf, __nbytes);
 460 }
 461 #endif
 462
 463 #ifndef HAVE_STRCASESTR
 464 char *rep_strcasestr(const char *haystack, const char *needle)
 465 {
 466         const char *s;
 467         size_t nlen = strlen(needle);
 468         for (s=haystack;*s;s++) {
 469                 if (toupper(*needle) == toupper(*s) &&
 470                     strncasecmp(s, needle, nlen) == 0) {
 471                         return (char *)((uintptr_t)s);
 472                 }
 473         }
 474         return NULL;
 475 }
 476 #endif
 477
 478 #ifndef HAVE_STRTOK_R
 479 /* based on GLIBC version, copyright Free Software Foundation */
 480 char *rep_strtok_r(char *s, const char *delim, char **save_ptr)
 481 {
 482         char *token;
 483
 484         if (s == NULL) s = *save_ptr;
 485
 486         s += strspn(s, delim);
 487         if (*s == '\0') {
 488                 *save_ptr = s;
 489                 return NULL;
 490         }
 491
 492         token = s;
 493         s = strpbrk(token, delim);
 494         if (s == NULL) {
 495                 *save_ptr = token + strlen(token);
 496         } else {
 497                 *s = '\0';
 498                 *save_ptr = s + 1;
 499         }
 500
 501         return token;
 502 }
 503 #endif
 504
 505 #ifndef HAVE_STRTOLL
 506 long long int rep_strtoll(const char *str, char **endptr, int base)
 507 {
 508 #ifdef HAVE_STRTOQ
 509         return strtoq(str, endptr, base);
 510 #elif defined(HAVE___STRTOLL)
 511         return __strtoll(str, endptr, base);
 512 #elif SIZEOF_LONG == SIZEOF_LONG_LONG
 513         return (long long int) strtol(str, endptr, base);
 514 #else
 515 # error "You need a strtoll function"
 516 #endif
 517 }
 518 #endif
 519
 520
 521 #ifndef HAVE_STRTOULL
 522 unsigned long long int rep_strtoull(const char *str, char **endptr, int base)
 523 {
 524 #ifdef HAVE_STRTOUQ
 525         return strtouq(str, endptr, base);
 526 #elif defined(HAVE___STRTOULL)
 527         return __strtoull(str, endptr, base);
 528 #elif SIZEOF_LONG == SIZEOF_LONG_LONG
 529         return (unsigned long long int) strtoul(str, endptr, base);
 530 #else
 531 # error "You need a strtoull function"
 532 #endif
 533 }
 534 #endif
 535
 536 #ifndef HAVE_SETENV
 537 int rep_setenv(const char *name, const char *value, int overwrite)
 538 {
 539         char *p;
 540         size_t l1, l2;
 541         int ret;
 542
 543         if (!overwrite && getenv(name)) {
 544                 return 0;
 545         }
 546
 547         l1 = strlen(name);
 548         l2 = strlen(value);
 549
 550         p = malloc(l1+l2+2);
 551         if (p == NULL) {
 552                 return -1;
 553         }
 554         memcpy(p, name, l1);
 555         p[l1] = '=';
 556         memcpy(p+l1+1, value, l2);
 557         p[l1+l2+1] = 0;
 558
 559         ret = putenv(p);
 560         if (ret != 0) {
 561                 free(p);
 562         }
 563
 564         return ret;
 565 }
 566 #endif
 567
 568 #ifndef HAVE_UNSETENV
 569 int rep_unsetenv(const char *name)
 570 {
 571         extern char **environ;
 572         size_t len = strlen(name);
 573         size_t i, count;
 574
 575         if (environ == NULL || getenv(name) == NULL) {
 576                 return 0;
 577         }
 578
 579         for (i=0;environ[i];i++) /* noop */ ;
 580
 581         count=i;
 582
 583         for (i=0;i<count;) {
 584                 if (strncmp(environ[i], name, len) == 0 && environ[i][len] == '=') {
 585                         /* note: we do _not_ free the old variable here. It is unsafe to
 586                            do so, as the pointer may not have come from malloc */
 587                         memmove(&environ[i], &environ[i+1], (count-i)*sizeof(char *));
 588                         count--;
 589                 } else {
 590                         i++;
 591                 }
 592         }
 593
 594         return 0;
 595 }
 596 #endif
 597
 598 #ifndef HAVE_UTIME
 599 int rep_utime(const char *filename, const struct utimbuf *buf)
 600 {
 601         errno = ENOSYS;
 602         return -1;
 603 }
 604 #endif
 605
 606 #ifndef HAVE_UTIMES
 607 int rep_utimes(const char *filename, const struct timeval tv[2])
 608 {
 609         struct utimbuf u;
 610
 611         u.actime = tv[0].tv_sec;
 612         if (tv[0].tv_usec > 500000) {
 613                 u.actime += 1;
 614         }
 615
 616         u.modtime = tv[1].tv_sec;
 617         if (tv[1].tv_usec > 500000) {
 618                 u.modtime += 1;
 619         }
 620
 621         return utime(filename, &u);
 622 }
 623 #endif
 624
 625 #ifndef HAVE_DUP2
 626 int rep_dup2(int oldfd, int newfd)
 627 {
 628         errno = ENOSYS;
 629         return -1;
 630 }
 631 #endif
 632
 633 #ifndef HAVE_CHOWN
 634 /**
 635 chown isn't used much but OS/2 doesn't have it
 636 **/
 637 int rep_chown(const char *fname, uid_t uid, gid_t gid)
 638 {
 639         errno = ENOSYS;
 640         return -1;
 641 }
 642 #endif
 643
 644 #ifndef HAVE_LINK
 645 int rep_link(const char *oldpath, const char *newpath)
 646 {
 647         errno = ENOSYS;
 648         return -1;
 649 }
 650 #endif
 651
 652 #ifndef HAVE_READLINK
 653 int rep_readlink(const char *path, char *buf, size_t bufsiz)
 654 {
 655         errno = ENOSYS;
 656         return -1;
 657 }
 658 #endif
 659
 660 #ifndef HAVE_SYMLINK
 661 int rep_symlink(const char *oldpath, const char *newpath)
 662 {
 663         errno = ENOSYS;
 664         return -1;
 665 }
 666 #endif
 667
 668 #ifndef HAVE_LCHOWN
 669 int rep_lchown(const char *fname,uid_t uid,gid_t gid)
 670 {
 671         errno = ENOSYS;
 672         return -1;
 673 }
 674 #endif
 675
 676 #ifndef HAVE_REALPATH
 677 char *rep_realpath(const char *path, char *resolved_path)
 678 {
 679         /* As realpath is not a system call we can't return ENOSYS. */
 680         errno = EINVAL;
 681         return NULL;
 682 }
 683 #endif
 684
 685
 686 #ifndef HAVE_MEMMEM
 687 void *rep_memmem(const void *haystack, size_t haystacklen,
 688                  const void *needle, size_t needlelen)
 689 {
 690         if (needlelen == 0) {
 691                 return discard_const(haystack);
 692         }
 693         while (haystacklen >= needlelen) {
 694                 char *p = memchr(haystack, *(const char *)needle,
 695                                  haystacklen-(needlelen-1));
 696                 if (!p) return NULL;
 697                 if (memcmp(p, needle, needlelen) == 0) {
 698                         return p;
 699                 }
 700                 haystack = p+1;
 701                 haystacklen -= (p - (const char *)haystack) + 1;
 702         }
 703         return NULL;
 704 }
 705 #endif
 706