archival/tar.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini tar implementation for busybox
   4  *
   5  * Modified to use common extraction code used by ar, cpio, dpkg-deb, dpkg
   6  *  by Glenn McGrath
   7  *
   8  * Note, that as of BusyBox-0.43, tar has been completely rewritten from the
   9  * ground up.  It still has remnants of the old code lying about, but it is
  10  * very different now (i.e., cleaner, less global variables, etc.)
  11  *
  12  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
  13  *
  14  * Based in part in the tar implementation in sash
  15  *  Copyright (c) 1999 by David I. Bell
  16  *  Permission is granted to use, distribute, or modify this source,
  17  *  provided that this copyright notice remains intact.
  18  *  Permission to distribute sash derived code under GPL has been granted.
  19  *
  20  * Based in part on the tar implementation from busybox-0.28
  21  *  Copyright (C) 1995 Bruce Perens
  22  *
  23  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  24  */
  25 //config:config TAR
  26 //config:       bool "tar (39 kb)"
  27 //config:       default y
  28 //config:       help
  29 //config:       tar is an archiving program. It's commonly used with gzip to
  30 //config:       create compressed archives. It's probably the most widely used
  31 //config:       UNIX archive program.
  32 //config:
  33 //config:config FEATURE_TAR_LONG_OPTIONS
  34 //config:       bool "Enable long options"
  35 //config:       default y
  36 //config:       depends on TAR && LONG_OPTS
  37 //config:
  38 //config:config FEATURE_TAR_CREATE
  39 //config:       bool "Enable -c (archive creation)"
  40 //config:       default y
  41 //config:       depends on TAR
  42 //config:
  43 //config:config FEATURE_TAR_AUTODETECT
  44 //config:       bool "Autodetect compressed tarballs"
  45 //config:       default y
  46 //config:       depends on TAR && (FEATURE_SEAMLESS_Z || FEATURE_SEAMLESS_GZ || FEATURE_SEAMLESS_BZ2 || FEATURE_SEAMLESS_LZMA || FEATURE_SEAMLESS_XZ)
  47 //config:       help
  48 //config:       With this option tar can automatically detect compressed
  49 //config:       tarballs. Currently it works only on files (not pipes etc).
  50 //config:
  51 //config:config FEATURE_TAR_FROM
  52 //config:       bool "Enable -X (exclude from) and -T (include from) options"
  53 //config:       default y
  54 //config:       depends on TAR
  55 //config:       help
  56 //config:       If you enable this option you'll be able to specify
  57 //config:       a list of files to include or exclude from an archive.
  58 //config:
  59 //config:config FEATURE_TAR_OLDGNU_COMPATIBILITY
  60 //config:       bool "Support old tar header format"
  61 //config:       default y
  62 //config:       depends on TAR || DPKG
  63 //config:       help
  64 //config:       This option is required to unpack archives created in
  65 //config:       the old GNU format; help to kill this old format by
  66 //config:       repacking your ancient archives with the new format.
  67 //config:
  68 //config:config FEATURE_TAR_OLDSUN_COMPATIBILITY
  69 //config:       bool "Enable untarring of tarballs with checksums produced by buggy Sun tar"
  70 //config:       default y
  71 //config:       depends on TAR || DPKG
  72 //config:       help
  73 //config:       This option is required to unpack archives created by some old
  74 //config:       version of Sun's tar (it was calculating checksum using signed
  75 //config:       arithmetic). It is said to be fixed in newer Sun tar, but "old"
  76 //config:       tarballs still exist.
  77 //config:
  78 //config:config FEATURE_TAR_GNU_EXTENSIONS
  79 //config:       bool "Support GNU tar extensions (long filenames)"
  80 //config:       default y
  81 //config:       depends on TAR || DPKG
  82 //config:
  83 //config:config FEATURE_TAR_TO_COMMAND
  84 //config:       bool "Support writing to an external program (--to-command)"
  85 //config:       default y
  86 //config:       depends on TAR && FEATURE_TAR_LONG_OPTIONS
  87 //config:       help
  88 //config:       If you enable this option you'll be able to instruct tar to send
  89 //config:       the contents of each extracted file to the standard input of an
  90 //config:       external program.
  91 //config:
  92 //config:config FEATURE_TAR_UNAME_GNAME
  93 //config:       bool "Enable use of user and group names"
  94 //config:       default y
  95 //config:       depends on TAR
  96 //config:       help
  97 //config:       Enable use of user and group names in tar. This affects contents
  98 //config:       listings (-t) and preserving permissions when unpacking (-p).
  99 //config:       +200 bytes.
 100 //config:
 101 //config:config FEATURE_TAR_NOPRESERVE_TIME
 102 //config:       bool "Enable -m (do not preserve time) GNU option"
 103 //config:       default y
 104 //config:       depends on TAR
 105 //config:
 106 //config:config FEATURE_TAR_SELINUX
 107 //config:       bool "Support extracting SELinux labels"
 108 //config:       default n
 109 //config:       depends on TAR && SELINUX
 110 //config:       help
 111 //config:       With this option busybox supports restoring SELinux labels
 112 //config:       when extracting files from tar archives.
 113
 114 //applet:IF_TAR(APPLET(tar, BB_DIR_BIN, BB_SUID_DROP))
 115
 116 //kbuild:lib-$(CONFIG_TAR) += tar.o
 117
 118 #include <fnmatch.h>
 119 #include "libbb.h"
 120 #include "common_bufsiz.h"
 121 #include "bb_archive.h"
 122 /* FIXME: Stop using this non-standard feature */
 123 #ifndef FNM_LEADING_DIR
 124 # define FNM_LEADING_DIR 0
 125 #endif
 126
 127 #if 0
 128 # define DBG(fmt, ...) bb_error_msg("%s: " fmt, __func__, ## __VA_ARGS__)
 129 #else
 130 # define DBG(...) ((void)0)
 131 #endif
 132 #define DBG_OPTION_PARSING 0
 133
 134
 135 #define block_buf bb_common_bufsiz1
 136 #define INIT_G() do { setup_common_bufsiz(); } while (0)
 137
 138
 139 #if ENABLE_FEATURE_TAR_CREATE
 140
 141 /*
 142 ** writeTarFile(), writeFileToTarball(), and writeTarHeader() are
 143 ** the only functions that deal with the HardLinkInfo structure.
 144 ** Even these functions use the xxxHardLinkInfo() functions.
 145 */
 146 typedef struct HardLinkInfo {
 147         struct HardLinkInfo *next; /* Next entry in list */
 148         dev_t dev;                 /* Device number */
 149         ino_t ino;                 /* Inode number */
 150 //      short linkCount;           /* (Hard) Link Count */
 151         char name[1];              /* Start of filename (must be last) */
 152 } HardLinkInfo;
 153
 154 /* Some info to be carried along when creating a new tarball */
 155 typedef struct TarBallInfo {
 156         int tarFd;                      /* Open-for-write file descriptor
 157                                          * for the tarball */
 158         int verboseFlag;                /* Whether to print extra stuff or not */
 159 # if ENABLE_FEATURE_TAR_FROM
 160         const llist_t *excludeList;     /* List of files to not include */
 161 # endif
 162         HardLinkInfo *hlInfoHead;       /* Hard Link Tracking Information */
 163         HardLinkInfo *hlInfo;           /* Hard Link Info for the current file */
 164 //TODO: save only st_dev + st_ino
 165         struct stat tarFileStatBuf;     /* Stat info for the tarball, letting
 166                                          * us know the inode and device that the
 167                                          * tarball lives, so we can avoid trying
 168                                          * to include the tarball into itself */
 169 } TarBallInfo;
 170
 171 /* A nice enum with all the possible tar file content types */
 172 enum {
 173         REGTYPE = '0',          /* regular file */
 174         REGTYPE0 = '\0',        /* regular file (ancient bug compat) */
 175         LNKTYPE = '1',          /* hard link */
 176         SYMTYPE = '2',          /* symbolic link */
 177         CHRTYPE = '3',          /* character special */
 178         BLKTYPE = '4',          /* block special */
 179         DIRTYPE = '5',          /* directory */
 180         FIFOTYPE = '6',         /* FIFO special */
 181         CONTTYPE = '7',         /* reserved */
 182         GNULONGLINK = 'K',      /* GNU long (>100 chars) link name */
 183         GNULONGNAME = 'L',      /* GNU long (>100 chars) file name */
 184 };
 185
 186 /* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */
 187 static void addHardLinkInfo(HardLinkInfo **hlInfoHeadPtr,
 188                                         struct stat *statbuf,
 189                                         const char *fileName)
 190 {
 191         /* Note: hlInfoHeadPtr can never be NULL! */
 192         HardLinkInfo *hlInfo;
 193
 194         hlInfo = xmalloc(sizeof(HardLinkInfo) + strlen(fileName));
 195         hlInfo->next = *hlInfoHeadPtr;
 196         *hlInfoHeadPtr = hlInfo;
 197         hlInfo->dev = statbuf->st_dev;
 198         hlInfo->ino = statbuf->st_ino;
 199 //      hlInfo->linkCount = statbuf->st_nlink;
 200         strcpy(hlInfo->name, fileName);
 201 }
 202
 203 static void freeHardLinkInfo(HardLinkInfo **hlInfoHeadPtr)
 204 {
 205         HardLinkInfo *hlInfo;
 206         HardLinkInfo *hlInfoNext;
 207
 208         if (hlInfoHeadPtr) {
 209                 hlInfo = *hlInfoHeadPtr;
 210                 while (hlInfo) {
 211                         hlInfoNext = hlInfo->next;
 212                         free(hlInfo);
 213                         hlInfo = hlInfoNext;
 214                 }
 215                 *hlInfoHeadPtr = NULL;
 216         }
 217 }
 218
 219 /* Might be faster (and bigger) if the dev/ino were stored in numeric order ;) */
 220 static HardLinkInfo *findHardLinkInfo(HardLinkInfo *hlInfo, struct stat *statbuf)
 221 {
 222         while (hlInfo) {
 223                 if (statbuf->st_ino == hlInfo->ino
 224                  && statbuf->st_dev == hlInfo->dev
 225                 ) {
 226                         DBG("found hardlink:'%s'", hlInfo->name);
 227                         break;
 228                 }
 229                 hlInfo = hlInfo->next;
 230         }
 231         return hlInfo;
 232 }
 233
 234 /* Put an octal string into the specified buffer.
 235  * The number is zero padded and possibly NUL terminated.
 236  * Stores low-order bits only if whole value does not fit. */
 237 static void putOctal(char *cp, int len, off_t value)
 238 {
 239         char tempBuffer[sizeof(off_t)*3 + 1];
 240         char *tempString = tempBuffer;
 241         int width;
 242
 243         width = sprintf(tempBuffer, "%0*"OFF_FMT"o", len, value);
 244         tempString += (width - len);
 245
 246         /* If string has leading zeroes, we can drop one */
 247         /* and field will have trailing '\0' */
 248         /* (increases chances of compat with other tars) */
 249         if (tempString[0] == '0')
 250                 tempString++;
 251
 252         /* Copy the string to the field */
 253         memcpy(cp, tempString, len);
 254 }
 255 #define PUT_OCTAL(a, b) putOctal((a), sizeof(a), (b))
 256
 257 static void chksum_and_xwrite(int fd, struct tar_header_t* hp)
 258 {
 259         /* POSIX says that checksum is done on unsigned bytes
 260          * (Sun and HP-UX gets it wrong... more details in
 261          * GNU tar source) */
 262         const unsigned char *cp;
 263         int chksum, size;
 264
 265         strcpy(hp->magic, "ustar  ");
 266
 267         /* Calculate and store the checksum (i.e., the sum of all of the bytes of
 268          * the header).  The checksum field must be filled with blanks for the
 269          * calculation.  The checksum field is formatted differently from the
 270          * other fields: it has 6 digits, a null, then a space -- rather than
 271          * digits, followed by a null like the other fields... */
 272         memset(hp->chksum, ' ', sizeof(hp->chksum));
 273         cp = (const unsigned char *) hp;
 274         chksum = 0;
 275         size = sizeof(*hp);
 276         do { chksum += *cp++; } while (--size);
 277         putOctal(hp->chksum, sizeof(hp->chksum)-1, chksum);
 278
 279         /* Now write the header out to disk */
 280         xwrite(fd, hp, sizeof(*hp));
 281 }
 282
 283 # if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 284 static void writeLongname(int fd, int type, const char *name, int dir)
 285 {
 286         struct prefilled {
 287                 char mode[8];             /* 100-107 */
 288                 char uid[8];              /* 108-115 */
 289                 char gid[8];              /* 116-123 */
 290                 char size[12];            /* 124-135 */
 291                 char mtime[12];           /* 136-147 */
 292         };
 293         struct tar_header_t header;
 294         int size;
 295
 296         memset(&header, 0, sizeof(header));
 297         header.typeflag = type;
 298         strcpy(header.name, "././@LongLink");
 299         /* This sets mode/uid/gid/mtime to "00...00<NUL>" strings */
 300         memset(header.mode, '0', sizeof(struct prefilled));
 301         header.mode [sizeof(header.mode ) - 1] = '\0';
 302         header.uid  [sizeof(header.uid  ) - 1] = '\0';
 303         header.gid  [sizeof(header.gid  ) - 1] = '\0';
 304         /* header.size is filled by '0' now, will be corrected below */
 305         header.mtime[sizeof(header.mtime) - 1] = '\0';
 306
 307         dir = !!dir; /* normalize: 0/1 */
 308         size = strlen(name) + 1 + dir; /* GNU tar uses strlen+1 */
 309         /* + dir: account for possible '/' */
 310
 311         PUT_OCTAL(header.size, size);
 312         chksum_and_xwrite(fd, &header);
 313
 314         /* Write filename[/] and pad the block. */
 315         /* dir=0: writes 'name<NUL>', pads */
 316         /* dir=1: writes 'name', writes '/<NUL>', pads */
 317         dir *= 2;
 318         xwrite(fd, name, size - dir);
 319         xwrite(fd, "/", dir);
 320         size = (-size) & (TAR_BLOCK_SIZE-1);
 321         memset(&header, 0, size);
 322         xwrite(fd, &header, size);
 323 }
 324 # endif
 325
 326 /* Write out a tar header for the specified file/directory/whatever */
 327 static int writeTarHeader(struct TarBallInfo *tbInfo,
 328                 const char *header_name, const char *fileName, struct stat *statbuf)
 329 {
 330         struct tar_header_t header;
 331
 332         memset(&header, 0, sizeof(header));
 333
 334         strncpy(header.name, header_name, sizeof(header.name));
 335
 336         /* POSIX says to mask mode with 07777. */
 337         PUT_OCTAL(header.mode, statbuf->st_mode & 07777);
 338         PUT_OCTAL(header.uid, statbuf->st_uid);
 339         PUT_OCTAL(header.gid, statbuf->st_gid);
 340         memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */
 341         /* users report that files with negative st_mtime cause trouble, so: */
 342         PUT_OCTAL(header.mtime, statbuf->st_mtime >= 0 ? statbuf->st_mtime : 0);
 343
 344         /* Enter the user and group names */
 345         safe_strncpy(header.uname, get_cached_username(statbuf->st_uid), sizeof(header.uname));
 346         safe_strncpy(header.gname, get_cached_groupname(statbuf->st_gid), sizeof(header.gname));
 347
 348         if (tbInfo->hlInfo) {
 349                 /* This is a hard link */
 350                 header.typeflag = LNKTYPE;
 351                 strncpy(header.linkname, tbInfo->hlInfo->name,
 352                                 sizeof(header.linkname));
 353 # if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 354                 /* Write out long linkname if needed */
 355                 if (header.linkname[sizeof(header.linkname)-1])
 356                         writeLongname(tbInfo->tarFd, GNULONGLINK,
 357                                         tbInfo->hlInfo->name, 0);
 358 # endif
 359         } else if (S_ISLNK(statbuf->st_mode)) {
 360                 char *lpath = xmalloc_readlink_or_warn(fileName);
 361                 if (!lpath)
 362                         return FALSE;
 363                 header.typeflag = SYMTYPE;
 364                 strncpy(header.linkname, lpath, sizeof(header.linkname));
 365 # if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 366                 /* Write out long linkname if needed */
 367                 if (header.linkname[sizeof(header.linkname)-1])
 368                         writeLongname(tbInfo->tarFd, GNULONGLINK, lpath, 0);
 369 # else
 370                 /* If it is larger than 100 bytes, bail out */
 371                 if (header.linkname[sizeof(header.linkname)-1]) {
 372                         free(lpath);
 373                         bb_simple_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
 374                         return FALSE;
 375                 }
 376 # endif
 377                 free(lpath);
 378         } else if (S_ISDIR(statbuf->st_mode)) {
 379                 header.typeflag = DIRTYPE;
 380                 /* Append '/' only if there is a space for it */
 381                 if (!header.name[sizeof(header.name)-1])
 382                         header.name[strlen(header.name)] = '/';
 383         } else if (S_ISCHR(statbuf->st_mode)) {
 384                 header.typeflag = CHRTYPE;
 385                 PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
 386                 PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
 387         } else if (S_ISBLK(statbuf->st_mode)) {
 388                 header.typeflag = BLKTYPE;
 389                 PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
 390                 PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
 391         } else if (S_ISFIFO(statbuf->st_mode)) {
 392                 header.typeflag = FIFOTYPE;
 393         } else if (S_ISREG(statbuf->st_mode)) {
 394                 /* header.size field is 12 bytes long */
 395                 /* Does octal-encoded size fit? */
 396                 uoff_t filesize = statbuf->st_size;
 397                 if (sizeof(filesize) <= 4
 398                  || filesize <= (uoff_t)0777777777777LL
 399                 ) {
 400                         PUT_OCTAL(header.size, filesize);
 401                 }
 402                 /* Does base256-encoded size fit?
 403                  * It always does unless off_t is wider than 64 bits.
 404                  */
 405                 else if (ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 406 # if ULLONG_MAX > 0xffffffffffffffffLL /* 2^64-1 */
 407                  && (filesize <= 0x3fffffffffffffffffffffffLL)
 408 # endif
 409                 ) {
 410                         /* GNU tar uses "base-256 encoding" for very large numbers.
 411                          * Encoding is binary, with highest bit always set as a marker
 412                          * and sign in next-highest bit:
 413                          * 80 00 .. 00 - zero
 414                          * bf ff .. ff - largest positive number
 415                          * ff ff .. ff - minus 1
 416                          * c0 00 .. 00 - smallest negative number
 417                          */
 418                         char *p8 = header.size + sizeof(header.size);
 419                         do {
 420                                 *--p8 = (uint8_t)filesize;
 421                                 filesize >>= 8;
 422                         } while (p8 != header.size);
 423                         *p8 |= 0x80;
 424                 } else {
 425                         bb_error_msg_and_die("can't store file '%s' "
 426                                 "of size %"OFF_FMT"u, aborting",
 427                                 fileName, statbuf->st_size);
 428                 }
 429                 header.typeflag = REGTYPE;
 430         } else {
 431                 bb_error_msg("%s: unknown file type", fileName);
 432                 return FALSE;
 433         }
 434
 435 # if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 436         /* Write out long name if needed */
 437         /* (we, like GNU tar, output long linkname *before* long name) */
 438         if (header.name[sizeof(header.name)-1])
 439                 writeLongname(tbInfo->tarFd, GNULONGNAME,
 440                                 header_name, S_ISDIR(statbuf->st_mode));
 441 # endif
 442
 443         /* Now write the header out to disk */
 444         chksum_and_xwrite(tbInfo->tarFd, &header);
 445
 446         /* Now do the verbose thing (or not) */
 447         if (tbInfo->verboseFlag) {
 448                 FILE *vbFd = stdout;
 449
 450                 /* If archive goes to stdout, verbose goes to stderr */
 451                 if (tbInfo->tarFd == STDOUT_FILENO)
 452                         vbFd = stderr;
 453                 /* GNU "tar cvvf" prints "extended" listing a-la "ls -l" */
 454                 /* We don't have such excesses here: for us "v" == "vv" */
 455                 /* '/' is probably a GNUism */
 456                 fprintf(vbFd, "%s%s\n", header_name,
 457                                 S_ISDIR(statbuf->st_mode) ? "/" : "");
 458         }
 459
 460         return TRUE;
 461 }
 462
 463 # if ENABLE_FEATURE_TAR_FROM
 464 static int exclude_file(const llist_t *excluded_files, const char *file)
 465 {
 466         while (excluded_files) {
 467                 if (excluded_files->data[0] == '/') {
 468                         if (fnmatch(excluded_files->data, file,
 469                                         FNM_PATHNAME | FNM_LEADING_DIR) == 0)
 470                                 return 1;
 471                 } else {
 472                         const char *p;
 473
 474                         for (p = file; p[0] != '\0'; p++) {
 475                                 if ((p == file || p[-1] == '/')
 476                                  && p[0] != '/'
 477                                  && fnmatch(excluded_files->data, p,
 478                                                 FNM_PATHNAME | FNM_LEADING_DIR) == 0
 479                                 ) {
 480                                         return 1;
 481                                 }
 482                         }
 483                 }
 484                 excluded_files = excluded_files->link;
 485         }
 486
 487         return 0;
 488 }
 489 # else
 490 #  define exclude_file(excluded_files, file) 0
 491 # endif
 492
 493 static int FAST_FUNC writeFileToTarball(const char *fileName, struct stat *statbuf,
 494                         void *userData, int depth UNUSED_PARAM)
 495 {
 496         struct TarBallInfo *tbInfo = (struct TarBallInfo *) userData;
 497         const char *header_name;
 498         int inputFileFd = -1;
 499
 500         DBG("writeFileToTarball('%s')", fileName);
 501
 502         /* Strip leading '/' and such (must be before memorizing hardlink's name) */
 503         header_name = strip_unsafe_prefix(fileName);
 504
 505         if (header_name[0] == '\0')
 506                 return TRUE;
 507
 508         /* It is against the rules to archive a socket */
 509         if (S_ISSOCK(statbuf->st_mode)) {
 510                 bb_error_msg("%s: socket ignored", fileName);
 511                 return TRUE;
 512         }
 513
 514         /*
 515          * Check to see if we are dealing with a hard link.
 516          * If so -
 517          * Treat the first occurrence of a given dev/inode as a file while
 518          * treating any additional occurrences as hard links.  This is done
 519          * by adding the file information to the HardLinkInfo linked list.
 520          */
 521         tbInfo->hlInfo = NULL;
 522         if (!S_ISDIR(statbuf->st_mode) && statbuf->st_nlink > 1) {
 523                 DBG("'%s': st_nlink > 1", header_name);
 524                 tbInfo->hlInfo = findHardLinkInfo(tbInfo->hlInfoHead, statbuf);
 525                 if (tbInfo->hlInfo == NULL) {
 526                         DBG("'%s': addHardLinkInfo", header_name);
 527                         addHardLinkInfo(&tbInfo->hlInfoHead, statbuf, header_name);
 528                 }
 529         }
 530
 531         /* It is a bad idea to store the archive we are in the process of creating,
 532          * so check the device and inode to be sure that this particular file isn't
 533          * the new tarball */
 534         if (tbInfo->tarFileStatBuf.st_dev == statbuf->st_dev
 535          && tbInfo->tarFileStatBuf.st_ino == statbuf->st_ino
 536         ) {
 537                 bb_error_msg("%s: file is the archive; skipping", fileName);
 538                 return TRUE;
 539         }
 540
 541         if (exclude_file(tbInfo->excludeList, header_name))
 542                 return SKIP;
 543
 544 # if !ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 545         if (strlen(header_name) >= NAME_SIZE) {
 546                 bb_simple_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
 547                 return TRUE;
 548         }
 549 # endif
 550
 551         /* Is this a regular file? */
 552         if (tbInfo->hlInfo == NULL && S_ISREG(statbuf->st_mode)) {
 553                 /* open the file we want to archive, and make sure all is well */
 554                 inputFileFd = open_or_warn(fileName, O_RDONLY);
 555                 if (inputFileFd < 0) {
 556                         return FALSE;
 557                 }
 558         }
 559
 560         /* Add an entry to the tarball */
 561         if (writeTarHeader(tbInfo, header_name, fileName, statbuf) == FALSE) {
 562                 return FALSE;
 563         }
 564
 565         /* If it was a regular file, write out the body */
 566         if (inputFileFd >= 0) {
 567                 size_t readSize;
 568                 /* Write the file to the archive. */
 569                 /* We record size into header first, */
 570                 /* and then write out file. If file shrinks in between, */
 571                 /* tar will be corrupted. So we don't allow for that. */
 572                 /* NB: GNU tar 1.16 warns and pads with zeroes */
 573                 /* or even seeks back and updates header */
 574                 bb_copyfd_exact_size(inputFileFd, tbInfo->tarFd, statbuf->st_size);
 575                 ////off_t readSize;
 576                 ////readSize = bb_copyfd_size(inputFileFd, tbInfo->tarFd, statbuf->st_size);
 577                 ////if (readSize != statbuf->st_size && readSize >= 0) {
 578                 ////    bb_error_msg_and_die("short read from %s, aborting", fileName);
 579                 ////}
 580
 581                 /* Check that file did not grow in between? */
 582                 /* if (safe_read(inputFileFd, 1) == 1) warn but continue? */
 583
 584                 close(inputFileFd);
 585
 586                 /* Pad the file up to the tar block size */
 587                 /* (a few tricks here in the name of code size) */
 588                 readSize = (-(int)statbuf->st_size) & (TAR_BLOCK_SIZE-1);
 589                 memset(block_buf, 0, readSize);
 590                 xwrite(tbInfo->tarFd, block_buf, readSize);
 591         }
 592
 593         return TRUE;
 594 }
 595
 596 # if SEAMLESS_COMPRESSION
 597 /* Don't inline: vfork scares gcc and pessimizes code */
 598 static void NOINLINE vfork_compressor(int tar_fd, const char *gzip)
 599 {
 600         // On Linux, vfork never unpauses parent early, although standard
 601         // allows for that. Do we want to waste bytes checking for it?
 602 #  define WAIT_FOR_CHILD 0
 603         volatile int vfork_exec_errno = 0;
 604         struct fd_pair data;
 605 #  if WAIT_FOR_CHILD
 606         struct fd_pair status;
 607         xpiped_pair(status);
 608 #  endif
 609         xpiped_pair(data);
 610
 611         signal(SIGPIPE, SIG_IGN); /* we only want EPIPE on errors */
 612
 613         if (xvfork() == 0) {
 614                 /* child */
 615                 int tfd;
 616                 /* NB: close _first_, then move fds! */
 617                 close(data.wr);
 618 #  if WAIT_FOR_CHILD
 619                 close(status.rd);
 620                 /* status.wr will close only on exec -
 621                  * parent waits for this close to happen */
 622                 fcntl(status.wr, F_SETFD, FD_CLOEXEC);
 623 #  endif
 624                 /* copy it: parent's tar_fd variable must not change */
 625                 tfd = tar_fd;
 626                 if (tfd == 0) {
 627                         /* Output tar fd may be zero.
 628                          * xmove_fd(data.rd, 0) would destroy it.
 629                          * Reproducer:
 630                          *  exec 0>&-
 631                          *  exec 1>&-
 632                          *  tar czf Z.tar.gz FILE
 633                          * Swapping move_fd's order wouldn't work:
 634                          * data.rd is 1 and _it_ would be destroyed.
 635                          */
 636                         tfd = dup(tfd);
 637                 }
 638                 xmove_fd(data.rd, 0);
 639                 xmove_fd(tfd, 1);
 640
 641                 /* exec gzip/bzip2/... program */
 642                 //BB_EXECLP(gzip, gzip, "-f", (char *)0); - WRONG for "xz",
 643                 // if xz is an enabled applet, it'll be a version which
 644                 // can only decompress. We do need to execute external
 645                 // program, not applet.
 646                 execlp(gzip, gzip, "-f", (char *)0);
 647
 648                 vfork_exec_errno = errno;
 649                 _exit(EXIT_FAILURE);
 650         }
 651
 652         /* parent */
 653         xmove_fd(data.wr, tar_fd);
 654         close(data.rd);
 655 #  if WAIT_FOR_CHILD
 656         close(status.wr);
 657         while (1) {
 658                 /* Wait until child execs (or fails to) */
 659                 char buf;
 660                 int n = full_read(status.rd, &buf, 1);
 661                 if (n < 0 /* && errno == EAGAIN */)
 662                         continue;       /* try it again */
 663         }
 664         close(status.rd);
 665 #  endif
 666         if (vfork_exec_errno) {
 667                 errno = vfork_exec_errno;
 668                 bb_perror_msg_and_die("can't execute '%s'", gzip);
 669         }
 670 }
 671 # endif /* SEAMLESS_COMPRESSION */
 672
 673
 674 # if !SEAMLESS_COMPRESSION
 675 /* Do not pass gzip flag to writeTarFile() */
 676 #define writeTarFile(tbInfo, recurseFlags, filelist, gzip) \
 677         writeTarFile(tbInfo, recurseFlags, filelist)
 678 # endif
 679 /* gcc 4.2.1 inlines it, making code bigger */
 680 static NOINLINE int writeTarFile(
 681         struct TarBallInfo *tbInfo,
 682         int recurseFlags,
 683         const llist_t *filelist,
 684         const char *gzip)
 685 {
 686         int errorFlag = FALSE;
 687
 688         /*tbInfo->hlInfoHead = NULL; - already is */
 689
 690         /* Store the stat info for the tarball's file, so
 691          * can avoid including the tarball into itself....  */
 692         xfstat(tbInfo->tarFd, &tbInfo->tarFileStatBuf, "can't stat tar file");
 693
 694 # if SEAMLESS_COMPRESSION
 695         if (gzip)
 696                 vfork_compressor(tbInfo->tarFd, gzip);
 697 # endif
 698
 699         /* Read the directory/files and iterate over them one at a time */
 700         while (filelist) {
 701                 if (!recursive_action(filelist->data, recurseFlags,
 702                                 writeFileToTarball, writeFileToTarball, tbInfo, 0)
 703                 ) {
 704                         errorFlag = TRUE;
 705                 }
 706                 filelist = filelist->link;
 707         }
 708         /* Write two empty blocks to the end of the archive */
 709         memset(block_buf, 0, 2*TAR_BLOCK_SIZE);
 710         xwrite(tbInfo->tarFd, block_buf, 2*TAR_BLOCK_SIZE);
 711
 712         /* To be pedantically correct, we would check if the tarball
 713          * is smaller than 20 tar blocks, and pad it if it was smaller,
 714          * but that isn't necessary for GNU tar interoperability, and
 715          * so is considered a waste of space */
 716
 717         /* Close so the child process (if any) will exit */
 718         close(tbInfo->tarFd);
 719
 720         /* Hang up the tools, close up shop, head home */
 721         if (ENABLE_FEATURE_CLEAN_UP)
 722                 freeHardLinkInfo(&tbInfo->hlInfoHead);
 723
 724         if (errorFlag)
 725                 bb_simple_error_msg("error exit delayed from previous errors");
 726
 727 # if SEAMLESS_COMPRESSION
 728         if (gzip) {
 729                 int status;
 730                 if (safe_waitpid(-1, &status, 0) == -1)
 731                         bb_simple_perror_msg("waitpid");
 732                 else if (!WIFEXITED(status) || WEXITSTATUS(status))
 733                         /* gzip was killed or has exited with nonzero! */
 734                         errorFlag = TRUE;
 735         }
 736 # endif
 737         return errorFlag;
 738 }
 739
 740 #endif /* FEATURE_TAR_CREATE */
 741
 742 #if ENABLE_FEATURE_TAR_FROM
 743 static llist_t *append_file_list_to_list(llist_t *list)
 744 {
 745         llist_t *newlist = NULL;
 746
 747         while (list) {
 748                 FILE *src_stream;
 749                 char *line;
 750
 751                 src_stream = xfopen_stdin(llist_pop(&list));
 752                 while ((line = xmalloc_fgetline(src_stream)) != NULL) {
 753                         /* kill trailing '/' unless the string is just "/" */
 754                         char *cp = last_char_is(line, '/');
 755                         if (cp > line)
 756                                 *cp = '\0';
 757                         llist_add_to_end(&newlist, line);
 758                 }
 759                 fclose(src_stream);
 760         }
 761         return newlist;
 762 }
 763 #endif
 764
 765 //usage:#define tar_trivial_usage
 766 //usage:        IF_FEATURE_TAR_CREATE("c|") "x|t [-"
 767 //usage:        IF_FEATURE_SEAMLESS_Z("Z")
 768 //usage:        IF_FEATURE_SEAMLESS_GZ("z")
 769 //usage:        IF_FEATURE_SEAMLESS_XZ("J")
 770 //usage:        IF_FEATURE_SEAMLESS_BZ2("j")
 771 //usage:        "a"
 772 //usage:        IF_FEATURE_TAR_CREATE("h")
 773 //usage:        IF_FEATURE_TAR_NOPRESERVE_TIME("m")
 774 //usage:        "vokO] "
 775 //usage:        "[-f TARFILE] [-C DIR] "
 776 //usage:        IF_FEATURE_TAR_FROM("[-T FILE] [-X FILE] "IF_FEATURE_TAR_LONG_OPTIONS("[--exclude PATTERN]... "))
 777 //usage:        "[FILE]..."
 778 //usage:#define tar_full_usage "\n\n"
 779 //usage:        IF_FEATURE_TAR_CREATE("Create, extract, ")
 780 //usage:        IF_NOT_FEATURE_TAR_CREATE("Extract ")
 781 //usage:        "or list files from a tar file"
 782 //usage:     "\n"
 783 //usage:        IF_FEATURE_TAR_CREATE(
 784 //usage:     "\n        c       Create"
 785 //usage:        )
 786 //usage:     "\n        x       Extract"
 787 //usage:     "\n        t       List"
 788 //usage:     "\n        -f FILE Name of TARFILE ('-' for stdin/out)"
 789 //usage:     "\n        -C DIR  Change to DIR before operation"
 790 //usage:     "\n        -v      Verbose"
 791 //usage:     "\n        -O      Extract to stdout"
 792 //usage:        IF_FEATURE_TAR_NOPRESERVE_TIME(
 793 //usage:     "\n        -m      Don't restore mtime"
 794 //usage:        )
 795 //usage:     "\n        -o      Don't restore user:group"
 796 ///////:-p - accepted but ignored, restores mode (aliases in GNU tar: --preserve-permissions, --same-permissions)
 797 //usage:     "\n        -k      Don't replace existing files"
 798 //usage:        IF_FEATURE_SEAMLESS_Z(
 799 //usage:     "\n        -Z      (De)compress using compress"
 800 //usage:        )
 801 //usage:        IF_FEATURE_SEAMLESS_GZ(
 802 //usage:     "\n        -z      (De)compress using gzip"
 803 //usage:        )
 804 //usage:        IF_FEATURE_SEAMLESS_XZ(
 805 //usage:     "\n        -J      (De)compress using xz"
 806 //usage:        )
 807 //usage:        IF_FEATURE_SEAMLESS_BZ2(
 808 //usage:     "\n        -j      (De)compress using bzip2"
 809 //usage:        )
 810 //usage:     "\n        -a      (De)compress based on extension"
 811 //usage:        IF_FEATURE_TAR_CREATE(
 812 //usage:     "\n        -h      Follow symlinks"
 813 //usage:        )
 814 //usage:        IF_FEATURE_TAR_FROM(
 815 //usage:     "\n        -T FILE File with names to include"
 816 //usage:     "\n        -X FILE File with glob patterns to exclude"
 817 //usage:        IF_FEATURE_TAR_LONG_OPTIONS(
 818 //usage:     "\n        --exclude PATTERN       Glob pattern to exclude"
 819 //usage:        )
 820 //usage:        )
 821 //usage:
 822 //usage:#define tar_example_usage
 823 //usage:       "$ zcat /tmp/tarball.tar.gz | tar -xf -\n"
 824 //usage:       "$ tar -cf /tmp/tarball.tar /usr/local\n"
 825
 826 // Supported but aren't in --help:
 827 //      lzma
 828 //      no-recursion
 829 //      numeric-owner
 830 //      no-same-permissions
 831 //      overwrite
 832 //IF_FEATURE_TAR_TO_COMMAND(
 833 //      to-command
 834 //)
 835
 836 enum {
 837         OPTBIT_KEEP_OLD = 8,
 838         IF_FEATURE_TAR_CREATE(   OPTBIT_CREATE      ,)
 839         IF_FEATURE_TAR_CREATE(   OPTBIT_DEREFERENCE ,)
 840         IF_FEATURE_SEAMLESS_BZ2( OPTBIT_BZIP2       ,)
 841         IF_FEATURE_TAR_FROM(     OPTBIT_INCLUDE_FROM,)
 842         IF_FEATURE_TAR_FROM(     OPTBIT_EXCLUDE_FROM,)
 843         IF_FEATURE_SEAMLESS_GZ(  OPTBIT_GZIP        ,)
 844         IF_FEATURE_SEAMLESS_XZ(  OPTBIT_XZ          ,)
 845         IF_FEATURE_SEAMLESS_Z(   OPTBIT_COMPRESS    ,) // 16th bit
 846         OPTBIT_AUTOCOMPRESS_BY_EXT,
 847         IF_FEATURE_TAR_NOPRESERVE_TIME(OPTBIT_NOPRESERVE_TIME,)
 848 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
 849         OPTBIT_STRIP_COMPONENTS,
 850         IF_FEATURE_SEAMLESS_LZMA(OPTBIT_LZMA        ,)
 851         OPTBIT_NORECURSION,
 852         IF_FEATURE_TAR_TO_COMMAND(OPTBIT_2COMMAND   ,)
 853         OPTBIT_NUMERIC_OWNER,
 854         OPTBIT_NOPRESERVE_PERM,
 855         OPTBIT_OVERWRITE,
 856 #endif
 857         OPT_TEST         = 1 << 0, // t
 858         OPT_EXTRACT      = 1 << 1, // x
 859         OPT_BASEDIR      = 1 << 2, // C
 860         OPT_TARNAME      = 1 << 3, // f
 861         OPT_2STDOUT      = 1 << 4, // O
 862         OPT_NOPRESERVE_OWNER = 1 << 5, // o == no-same-owner
 863         OPT_P            = 1 << 6, // p
 864         OPT_VERBOSE      = 1 << 7, // v
 865         OPT_KEEP_OLD     = 1 << 8, // k
 866         OPT_CREATE       = IF_FEATURE_TAR_CREATE(   (1 << OPTBIT_CREATE      )) + 0, // c
 867         OPT_DEREFERENCE  = IF_FEATURE_TAR_CREATE(   (1 << OPTBIT_DEREFERENCE )) + 0, // h
 868         OPT_BZIP2        = IF_FEATURE_SEAMLESS_BZ2( (1 << OPTBIT_BZIP2       )) + 0, // j
 869         OPT_INCLUDE_FROM = IF_FEATURE_TAR_FROM(     (1 << OPTBIT_INCLUDE_FROM)) + 0, // T
 870         OPT_EXCLUDE_FROM = IF_FEATURE_TAR_FROM(     (1 << OPTBIT_EXCLUDE_FROM)) + 0, // X
 871         OPT_GZIP         = IF_FEATURE_SEAMLESS_GZ(  (1 << OPTBIT_GZIP        )) + 0, // z
 872         OPT_XZ           = IF_FEATURE_SEAMLESS_XZ(  (1 << OPTBIT_XZ          )) + 0, // J
 873         OPT_COMPRESS     = IF_FEATURE_SEAMLESS_Z(   (1 << OPTBIT_COMPRESS    )) + 0, // Z
 874         OPT_AUTOCOMPRESS_BY_EXT = 1 << OPTBIT_AUTOCOMPRESS_BY_EXT,                   // a
 875         OPT_NOPRESERVE_TIME  = IF_FEATURE_TAR_NOPRESERVE_TIME((1 << OPTBIT_NOPRESERVE_TIME)) + 0, // m
 876         OPT_STRIP_COMPONENTS = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_STRIP_COMPONENTS)) + 0, // strip-components
 877         OPT_LZMA             = IF_FEATURE_TAR_LONG_OPTIONS(IF_FEATURE_SEAMLESS_LZMA((1 << OPTBIT_LZMA))) + 0, // lzma
 878         OPT_NORECURSION      = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NORECURSION    )) + 0, // no-recursion
 879         OPT_2COMMAND         = IF_FEATURE_TAR_TO_COMMAND(  (1 << OPTBIT_2COMMAND       )) + 0, // to-command
 880         OPT_NUMERIC_OWNER    = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NUMERIC_OWNER  )) + 0, // numeric-owner
 881         OPT_NOPRESERVE_PERM  = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NOPRESERVE_PERM)) + 0, // no-same-permissions
 882         OPT_OVERWRITE        = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_OVERWRITE      )) + 0, // overwrite
 883
 884         OPT_ANY_COMPRESS = (OPT_BZIP2 | OPT_LZMA | OPT_GZIP | OPT_XZ | OPT_COMPRESS),
 885 };
 886 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
 887 static const char tar_longopts[] ALIGN1 =
 888         "list\0"                No_argument       "t"
 889         "extract\0"             No_argument       "x"
 890         "directory\0"           Required_argument "C"
 891         "file\0"                Required_argument "f"
 892         "to-stdout\0"           No_argument       "O"
 893         /* do not restore owner */
 894         /* Note: GNU tar handles 'o' as no-same-owner only on extract,
 895          * on create, 'o' is --old-archive. We do not support --old-archive. */
 896         "no-same-owner\0"       No_argument       "o"
 897         "same-permissions\0"    No_argument       "p"
 898         "verbose\0"             No_argument       "v"
 899         "keep-old\0"            No_argument       "k"
 900 # if ENABLE_FEATURE_TAR_CREATE
 901         "create\0"              No_argument       "c"
 902         "dereference\0"         No_argument       "h"
 903 # endif
 904 # if ENABLE_FEATURE_SEAMLESS_BZ2
 905         "bzip2\0"               No_argument       "j"
 906 # endif
 907 # if ENABLE_FEATURE_TAR_FROM
 908         "files-from\0"          Required_argument "T"
 909         "exclude-from\0"        Required_argument "X"
 910 # endif
 911 # if ENABLE_FEATURE_SEAMLESS_GZ
 912         "gzip\0"                No_argument       "z"
 913 # endif
 914 # if ENABLE_FEATURE_SEAMLESS_XZ
 915         "xz\0"                  No_argument       "J"
 916 # endif
 917 # if ENABLE_FEATURE_SEAMLESS_Z
 918         "compress\0"            No_argument       "Z"
 919 # endif
 920         "auto-compress\0"       No_argument       "a"
 921 # if ENABLE_FEATURE_TAR_NOPRESERVE_TIME
 922         "touch\0"               No_argument       "m"
 923 # endif
 924         "strip-components\0"    Required_argument "\xf8"
 925 # if ENABLE_FEATURE_SEAMLESS_LZMA
 926         "lzma\0"                No_argument       "\xf9"
 927 # endif
 928         "no-recursion\0"        No_argument       "\xfa"
 929 # if ENABLE_FEATURE_TAR_TO_COMMAND
 930         "to-command\0"          Required_argument "\xfb"
 931 # endif
 932         /* use numeric uid/gid from tar header, not textual */
 933         "numeric-owner\0"       No_argument       "\xfc"
 934         /* do not restore mode */
 935         "no-same-permissions\0" No_argument       "\xfd"
 936         /* on unpack, open with O_TRUNC and !O_EXCL */
 937         "overwrite\0"           No_argument       "\xfe"
 938         /* --exclude takes next bit position in option mask, */
 939         /* therefore we have to put it _after_ --no-same-permissions */
 940 # if ENABLE_FEATURE_TAR_FROM
 941         "exclude\0"             Required_argument "\xff"
 942 # endif
 943         ;
 944 # define GETOPT32 getopt32long
 945 # define LONGOPTS ,tar_longopts
 946 #else
 947 # define GETOPT32 getopt32
 948 # define LONGOPTS
 949 #endif
 950
 951 int tar_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 952 int tar_main(int argc UNUSED_PARAM, char **argv)
 953 {
 954         archive_handle_t *tar_handle;
 955         char *base_dir = NULL;
 956         const char *tar_filename = "-";
 957         unsigned opt;
 958         int verboseFlag = 0;
 959 #if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
 960         llist_t *excludes = NULL;
 961 #endif
 962         INIT_G();
 963
 964         /* Initialise default values */
 965         tar_handle = init_handle();
 966         tar_handle->ah_flags = ARCHIVE_CREATE_LEADING_DIRS
 967                              | ARCHIVE_RESTORE_DATE
 968                              | ARCHIVE_UNLINK_OLD;
 969
 970         /* Apparently only root's tar preserves perms (see bug 3844) */
 971         if (getuid() != 0)
 972                 tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_PERM;
 973
 974 #if ENABLE_DESKTOP
 975         /* Lie to buildroot when it starts asking stupid questions. */
 976         if (argv[1] && strcmp(argv[1], "--version") == 0) {
 977                 // Output of 'tar --version' examples:
 978                 // tar (GNU tar) 1.15.1
 979                 // tar (GNU tar) 1.25
 980                 // bsdtar 2.8.3 - libarchive 2.8.3
 981                 puts("tar (busybox) " BB_VER);
 982                 return 0;
 983         }
 984 #endif
 985         if (argv[1] && argv[1][0] != '-' && argv[1][0] != '\0') {
 986                 /* Compat:
 987                  * 1st argument without dash handles options with parameters
 988                  * differently from dashed one: it takes *next argv[i]*
 989                  * as parameter even if there are more chars in 1st argument:
 990                  *  "tar fx TARFILE" - "x" is not taken as f's param
 991                  *  but is interpreted as -x option
 992                  *  "tar -xf TARFILE" - dashed equivalent of the above
 993                  *  "tar -fx ..." - "x" is taken as f's param
 994                  * getopt32 wouldn't handle 1st command correctly.
 995                  * Unfortunately, people do use such commands.
 996                  * We massage argv[1] to work around it by moving 'f'
 997                  * to the end of the string.
 998                  * More contrived "tar fCx TARFILE DIR" still fails,
 999                  * but such commands are much less likely to be used.
1000                  */
1001                 char *f = strchr(argv[1], 'f');
1002                 if (f) {
1003                         while (f[1] != '\0') {
1004                                 *f = f[1];
1005                                 f++;
1006                         }
1007                         *f = 'f';
1008                 }
1009                 /* Prepend '-' to the first argument  */
1010                 argv[1] = xasprintf("-%s", argv[1]);
1011         }
1012         opt = GETOPT32(argv, "^"
1013                 "txC:f:Oopvk"
1014                 IF_FEATURE_TAR_CREATE(   "ch"    )
1015                 IF_FEATURE_SEAMLESS_BZ2( "j"     )
1016                 IF_FEATURE_TAR_FROM(     "T:*X:*")
1017                 IF_FEATURE_SEAMLESS_GZ(  "z"     )
1018                 IF_FEATURE_SEAMLESS_XZ(  "J"     )
1019                 IF_FEATURE_SEAMLESS_Z(   "Z"     )
1020                 "a"
1021                 IF_FEATURE_TAR_NOPRESERVE_TIME("m")
1022                 IF_FEATURE_TAR_LONG_OPTIONS("\xf8:") // --strip-components
1023                 "\0"
1024                 "tt:vv:" // count -t,-v
1025 #if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
1026                 "\xff::" // --exclude=PATTERN is a list
1027 #endif
1028                 IF_FEATURE_TAR_CREATE("c:") "t:x:" // at least one of these is reqd
1029                 IF_FEATURE_TAR_CREATE("c--tx:t--cx:x--ct") // mutually exclusive
1030                 IF_NOT_FEATURE_TAR_CREATE("t--x:x--t") // mutually exclusive
1031 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
1032                 ":\xf8+" // --strip-components=NUM
1033 #endif
1034                 LONGOPTS
1035                 , &base_dir // -C dir
1036                 , &tar_filename // -f filename
1037                 IF_FEATURE_TAR_FROM(, &(tar_handle->accept)) // T
1038                 IF_FEATURE_TAR_FROM(, &(tar_handle->reject)) // X
1039 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
1040                 , &tar_handle->tar__strip_components // --strip-components
1041 #endif
1042                 IF_FEATURE_TAR_TO_COMMAND(, &(tar_handle->tar__to_command)) // --to-command
1043 #if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
1044                 , &excludes // --exclude
1045 #endif
1046                 , &verboseFlag // combined count for -t and -v
1047                 , &verboseFlag // combined count for -t and -v
1048                 );
1049 #if DBG_OPTION_PARSING
1050         bb_error_msg("opt: 0x%08x", opt);
1051 # define showopt(o) bb_error_msg("opt & %s(%x):\t%x", #o, o, opt & o);
1052         showopt(OPT_TEST            );
1053         showopt(OPT_EXTRACT         );
1054         showopt(OPT_BASEDIR         );
1055         showopt(OPT_TARNAME         );
1056         showopt(OPT_2STDOUT         );
1057         showopt(OPT_NOPRESERVE_OWNER);
1058         showopt(OPT_P               );
1059         showopt(OPT_VERBOSE         );
1060         showopt(OPT_KEEP_OLD        );
1061         showopt(OPT_CREATE          );
1062         showopt(OPT_DEREFERENCE     );
1063         showopt(OPT_BZIP2           );
1064         showopt(OPT_INCLUDE_FROM    );
1065         showopt(OPT_EXCLUDE_FROM    );
1066         showopt(OPT_GZIP            );
1067         showopt(OPT_XZ              );
1068         showopt(OPT_COMPRESS        );
1069         showopt(OPT_AUTOCOMPRESS_BY_EXT);
1070         showopt(OPT_NOPRESERVE_TIME );
1071         showopt(OPT_STRIP_COMPONENTS);
1072         showopt(OPT_LZMA            );
1073         showopt(OPT_NORECURSION     );
1074         showopt(OPT_2COMMAND        );
1075         showopt(OPT_NUMERIC_OWNER   );
1076         showopt(OPT_NOPRESERVE_PERM );
1077         showopt(OPT_OVERWRITE       );
1078         showopt(OPT_ANY_COMPRESS    );
1079         bb_error_msg("base_dir:'%s'", base_dir);
1080         bb_error_msg("tar_filename:'%s'", tar_filename);
1081         bb_error_msg("verboseFlag:%d", verboseFlag);
1082         bb_error_msg("tar_handle->tar__to_command:'%s'", tar_handle->tar__to_command);
1083         bb_error_msg("tar_handle->tar__strip_components:%u", tar_handle->tar__strip_components);
1084         return 0;
1085 # undef showopt
1086 #endif
1087         argv += optind;
1088
1089         if (verboseFlag)
1090                 tar_handle->action_header = header_verbose_list;
1091         if (verboseFlag == 1)
1092                 tar_handle->action_header = header_list;
1093
1094         if (opt & OPT_EXTRACT)
1095                 tar_handle->action_data = data_extract_all;
1096
1097         if (opt & OPT_2STDOUT)
1098                 tar_handle->action_data = data_extract_to_stdout;
1099
1100         if (opt & OPT_2COMMAND) {
1101                 putenv((char*)"TAR_FILETYPE=f");
1102                 signal(SIGPIPE, SIG_IGN);
1103                 tar_handle->action_data = data_extract_to_command;
1104                 IF_FEATURE_TAR_TO_COMMAND(tar_handle->tar__to_command_shell = xstrdup(get_shell_name());)
1105         }
1106
1107         if (opt & OPT_KEEP_OLD)
1108                 tar_handle->ah_flags &= ~ARCHIVE_UNLINK_OLD;
1109
1110         if (opt & OPT_NUMERIC_OWNER)
1111                 tar_handle->ah_flags |= ARCHIVE_NUMERIC_OWNER;
1112
1113         if (opt & OPT_NOPRESERVE_OWNER)
1114                 tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_OWNER;
1115
1116         if (opt & OPT_NOPRESERVE_PERM)
1117                 tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_PERM;
1118
1119         if (opt & OPT_OVERWRITE) {
1120                 tar_handle->ah_flags &= ~ARCHIVE_UNLINK_OLD;
1121                 tar_handle->ah_flags |= ARCHIVE_O_TRUNC;
1122         }
1123
1124         if (opt & OPT_NOPRESERVE_TIME)
1125                 tar_handle->ah_flags &= ~ARCHIVE_RESTORE_DATE;
1126
1127 #if ENABLE_FEATURE_TAR_FROM
1128         tar_handle->reject = append_file_list_to_list(tar_handle->reject);
1129 # if ENABLE_FEATURE_TAR_LONG_OPTIONS
1130         /* Append excludes to reject */
1131         while (excludes) {
1132                 llist_t *next = excludes->link;
1133                 excludes->link = tar_handle->reject;
1134                 tar_handle->reject = excludes;
1135                 excludes = next;
1136         }
1137 # endif
1138         tar_handle->accept = append_file_list_to_list(tar_handle->accept);
1139 #endif
1140
1141         /* Setup an array of filenames to work with */
1142         /* TODO: This is the same as in ar, make a separate function? */
1143         while (*argv) {
1144                 /* kill trailing '/' unless the string is just "/" */
1145                 char *cp = last_char_is(*argv, '/');
1146                 if (cp > *argv)
1147                         *cp = '\0';
1148                 llist_add_to_end(&tar_handle->accept, *argv);
1149                 argv++;
1150         }
1151
1152         if (tar_handle->accept || tar_handle->reject)
1153                 tar_handle->filter = filter_accept_reject_list;
1154
1155         /* Open the tar file */
1156         {
1157                 int tar_fd = STDIN_FILENO;
1158                 int flags = O_RDONLY;
1159
1160                 if (opt & OPT_CREATE) {
1161                         /* Make sure there is at least one file to tar up */
1162                         if (tar_handle->accept == NULL)
1163                                 bb_simple_error_msg_and_die("empty archive");
1164
1165                         tar_fd = STDOUT_FILENO;
1166                         /* Mimicking GNU tar 1.15.1: */
1167                         flags = O_WRONLY | O_CREAT | O_TRUNC;
1168                 }
1169
1170                 if (LONE_DASH(tar_filename)) {
1171                         tar_handle->src_fd = tar_fd;
1172                         tar_handle->seek = seek_by_read;
1173                 } else
1174                 if (ENABLE_FEATURE_TAR_AUTODETECT
1175                  && ENABLE_FEATURE_SEAMLESS_LZMA
1176                  && flags == O_RDONLY
1177                  && !(opt & OPT_ANY_COMPRESS)
1178                  && is_suffixed_with(tar_filename, ".lzma")
1179                 /* We do this only for .lzma files, they have no signature.
1180                  * All other compression formats are recognized in
1181                  * get_header_tar() when first tar block has invalid format.
1182                  * Doing it here for all filenames would falsely trigger
1183                  * on e.g. tarball with 1st file named "BZh5".
1184                  */
1185                 ) {
1186                         tar_handle->src_fd = open_zipped(tar_filename, /*fail_if_not_compressed:*/ 0);
1187                         if (tar_handle->src_fd < 0)
1188                                 bb_perror_msg_and_die("can't open '%s'", tar_filename);
1189                 } else {
1190                         tar_handle->src_fd = xopen(tar_filename, flags);
1191 #if ENABLE_FEATURE_TAR_CREATE
1192                         if ((OPT_GZIP | OPT_BZIP2 | OPT_XZ | OPT_LZMA) != 0 /* at least one is config-enabled */
1193                          && (opt & OPT_AUTOCOMPRESS_BY_EXT)
1194                          && flags != O_RDONLY
1195                         ) {
1196                                 if (OPT_GZIP != 0 && is_suffixed_with(tar_filename, "gz"))
1197                                         opt |= OPT_GZIP;
1198                                 if (OPT_BZIP2 != 0 && is_suffixed_with(tar_filename, "bz2"))
1199                                         opt |= OPT_BZIP2;
1200                                 if (OPT_XZ != 0 && is_suffixed_with(tar_filename, "xz"))
1201                                         opt |= OPT_XZ;
1202                                 if (OPT_LZMA != 0 && is_suffixed_with(tar_filename, "lzma"))
1203                                         opt |= OPT_LZMA;
1204                         }
1205 #endif
1206                 }
1207         }
1208
1209         if (base_dir)
1210                 xchdir(base_dir);
1211
1212 #if ENABLE_FEATURE_TAR_CREATE
1213         /* Create an archive */
1214         if (opt & OPT_CREATE) {
1215                 struct TarBallInfo *tbInfo;
1216 # if SEAMLESS_COMPRESSION
1217                 const char *zipMode = NULL;
1218                 if (opt & OPT_COMPRESS)
1219                         zipMode = "compress";
1220                 if (opt & OPT_GZIP)
1221                         zipMode = "gzip";
1222                 if (opt & OPT_BZIP2)
1223                         zipMode = "bzip2";
1224                 if (opt & OPT_LZMA)
1225                         zipMode = "lzma";
1226                 if (opt & OPT_XZ)
1227                         zipMode = "xz";
1228 # endif
1229                 tbInfo = xzalloc(sizeof(*tbInfo));
1230                 tbInfo->tarFd = tar_handle->src_fd;
1231                 tbInfo->verboseFlag = verboseFlag;
1232 # if ENABLE_FEATURE_TAR_FROM
1233                 tbInfo->excludeList = tar_handle->reject;
1234 # endif
1235                 /* NB: writeTarFile() closes tar_handle->src_fd */
1236                 return writeTarFile(tbInfo,
1237                                 (opt & OPT_DEREFERENCE ? ACTION_FOLLOWLINKS : 0)
1238                                 | (opt & OPT_NORECURSION ? 0 : ACTION_RECURSE),
1239                                 tar_handle->accept,
1240                                 zipMode);
1241         }
1242 #endif
1243
1244         if (opt & OPT_ANY_COMPRESS) {
1245                 USE_FOR_MMU(IF_DESKTOP(long long) int FAST_FUNC (*xformer)(transformer_state_t *xstate);)
1246                 USE_FOR_NOMMU(const char *xformer_prog;)
1247
1248                 if (opt & OPT_COMPRESS) {
1249                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_Z(xformer = unpack_Z_stream;))
1250                         USE_FOR_NOMMU(xformer_prog = "uncompress";)
1251                 }
1252                 if (opt & OPT_GZIP) {
1253                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_GZ(xformer = unpack_gz_stream;))
1254                         USE_FOR_NOMMU(xformer_prog = "gunzip";)
1255                 }
1256                 if (opt & OPT_BZIP2) {
1257                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_BZ2(xformer = unpack_bz2_stream;))
1258                         USE_FOR_NOMMU(xformer_prog = "bunzip2";)
1259                 }
1260                 if (opt & OPT_LZMA) {
1261                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_LZMA(xformer = unpack_lzma_stream;))
1262                         USE_FOR_NOMMU(xformer_prog = "unlzma";)
1263                 }
1264                 if (opt & OPT_XZ) {
1265                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_XZ(xformer = unpack_xz_stream;))
1266                         USE_FOR_NOMMU(xformer_prog = "unxz";)
1267                 }
1268
1269                 fork_transformer_with_sig(tar_handle->src_fd, xformer, xformer_prog);
1270                 /* Can't lseek over pipes */
1271                 tar_handle->seek = seek_by_read;
1272                 /*tar_handle->offset = 0; - already is */
1273         }
1274
1275         /* Zero processed headers (== empty file) is not a valid tarball.
1276          * We (ab)use bb_got_signal as exitcode here,
1277          * because check_errors_in_children() uses _it_ as error indicator.
1278          */
1279         bb_got_signal = EXIT_FAILURE;
1280
1281         while (get_header_tar(tar_handle) == EXIT_SUCCESS)
1282                 bb_got_signal = EXIT_SUCCESS; /* saw at least one header, good */
1283
1284         create_links_from_list(tar_handle->link_placeholders);
1285
1286         /* Check that every file that should have been extracted was */
1287         while (tar_handle->accept) {
1288                 if (!find_list_entry(tar_handle->reject, tar_handle->accept->data)
1289                  && !find_list_entry(tar_handle->passed, tar_handle->accept->data)
1290                 ) {
1291                         bb_error_msg_and_die("%s: not found in archive",
1292                                 tar_handle->accept->data);
1293                 }
1294                 tar_handle->accept = tar_handle->accept->link;
1295         }
1296         if (ENABLE_FEATURE_CLEAN_UP /* && tar_handle->src_fd != STDIN_FILENO */)
1297                 close(tar_handle->src_fd);
1298
1299         if (SEAMLESS_COMPRESSION || OPT_COMPRESS) {
1300                 /* Set bb_got_signal to 1 if a child died with !0 exitcode */
1301                 check_errors_in_children(0);
1302         }
1303
1304         return bb_got_signal;
1305 }