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 /* TODO: security with -C DESTDIR option can be enhanced.
  26  * Consider tar file created via:
  27  * $ tar cvf bug.tar anything.txt
  28  * $ ln -s /tmp symlink
  29  * $ tar --append -f bug.tar symlink
  30  * $ rm symlink
  31  * $ mkdir symlink
  32  * $ tar --append -f bug.tar symlink/evil.py
  33  *
  34  * This will result in an archive which contains:
  35  * $ tar --list -f bug.tar
  36  * anything.txt
  37  * symlink
  38  * symlink/evil.py
  39  *
  40  * Untarring it puts evil.py in '/tmp' even if the -C DESTDIR is given.
  41  * This doesn't feel right, and IIRC GNU tar doesn't do that.
  42  */
  43
  44 //config:config TAR
  45 //config:       bool "tar"
  46 //config:       default y
  47 //config:       help
  48 //config:         tar is an archiving program. It's commonly used with gzip to
  49 //config:         create compressed archives. It's probably the most widely used
  50 //config:         UNIX archive program.
  51 //config:
  52 //config:config FEATURE_TAR_CREATE
  53 //config:       bool "Enable archive creation"
  54 //config:       default y
  55 //config:       depends on TAR
  56 //config:       help
  57 //config:         If you enable this option you'll be able to create
  58 //config:         tar archives using the `-c' option.
  59 //config:
  60 //config:config FEATURE_TAR_AUTODETECT
  61 //config:       bool "Autodetect compressed tarballs"
  62 //config:       default y
  63 //config:       depends on TAR && (FEATURE_SEAMLESS_Z || FEATURE_SEAMLESS_GZ || FEATURE_SEAMLESS_BZ2 || FEATURE_SEAMLESS_LZMA || FEATURE_SEAMLESS_XZ)
  64 //config:       help
  65 //config:         With this option tar can automatically detect compressed
  66 //config:         tarballs. Currently it works only on files (not pipes etc).
  67 //config:
  68 //config:config FEATURE_TAR_FROM
  69 //config:       bool "Enable -X (exclude from) and -T (include from) options)"
  70 //config:       default y
  71 //config:       depends on TAR
  72 //config:       help
  73 //config:         If you enable this option you'll be able to specify
  74 //config:         a list of files to include or exclude from an archive.
  75 //config:
  76 //config:config FEATURE_TAR_OLDGNU_COMPATIBILITY
  77 //config:       bool "Support for old tar header format"
  78 //config:       default y
  79 //config:       depends on TAR || DPKG
  80 //config:       help
  81 //config:         This option is required to unpack archives created in
  82 //config:         the old GNU format; help to kill this old format by
  83 //config:         repacking your ancient archives with the new format.
  84 //config:
  85 //config:config FEATURE_TAR_OLDSUN_COMPATIBILITY
  86 //config:       bool "Enable untarring of tarballs with checksums produced by buggy Sun tar"
  87 //config:       default y
  88 //config:       depends on TAR || DPKG
  89 //config:       help
  90 //config:         This option is required to unpack archives created by some old
  91 //config:         version of Sun's tar (it was calculating checksum using signed
  92 //config:         arithmetic). It is said to be fixed in newer Sun tar, but "old"
  93 //config:         tarballs still exist.
  94 //config:
  95 //config:config FEATURE_TAR_GNU_EXTENSIONS
  96 //config:       bool "Support for GNU tar extensions (long filenames)"
  97 //config:       default y
  98 //config:       depends on TAR || DPKG
  99 //config:       help
 100 //config:         With this option busybox supports GNU long filenames and
 101 //config:         linknames.
 102 //config:
 103 //config:config FEATURE_TAR_LONG_OPTIONS
 104 //config:       bool "Enable long options"
 105 //config:       default y
 106 //config:       depends on TAR && LONG_OPTS
 107 //config:       help
 108 //config:         Enable use of long options, increases size by about 400 Bytes
 109 //config:
 110 //config:config FEATURE_TAR_TO_COMMAND
 111 //config:       bool "Support for writing to an external program"
 112 //config:       default y
 113 //config:       depends on TAR && FEATURE_TAR_LONG_OPTIONS
 114 //config:       help
 115 //config:         If you enable this option you'll be able to instruct tar to send
 116 //config:         the contents of each extracted file to the standard input of an
 117 //config:         external program.
 118 //config:
 119 //config:config FEATURE_TAR_UNAME_GNAME
 120 //config:       bool "Enable use of user and group names"
 121 //config:       default y
 122 //config:       depends on TAR
 123 //config:       help
 124 //config:         Enables use of user and group names in tar. This affects contents
 125 //config:         listings (-t) and preserving permissions when unpacking (-p).
 126 //config:         +200 bytes.
 127 //config:
 128 //config:config FEATURE_TAR_NOPRESERVE_TIME
 129 //config:       bool "Enable -m (do not preserve time) option"
 130 //config:       default y
 131 //config:       depends on TAR
 132 //config:       help
 133 //config:         With this option busybox supports GNU tar -m
 134 //config:         (do not preserve time) option.
 135 //config:
 136 //config:config FEATURE_TAR_SELINUX
 137 //config:       bool "Support for extracting SELinux labels"
 138 //config:       default n
 139 //config:       depends on TAR && SELINUX
 140 //config:       help
 141 //config:         With this option busybox supports restoring SELinux labels
 142 //config:         when extracting files from tar archives.
 143
 144 //applet:IF_TAR(APPLET(tar, BB_DIR_BIN, BB_SUID_DROP))
 145 //kbuild:lib-$(CONFIG_TAR) += tar.o
 146
 147 #include <fnmatch.h>
 148 #include "libbb.h"
 149 #include "common_bufsiz.h"
 150 #include "bb_archive.h"
 151 /* FIXME: Stop using this non-standard feature */
 152 #ifndef FNM_LEADING_DIR
 153 # define FNM_LEADING_DIR 0
 154 #endif
 155
 156 #if 0
 157 # define DBG(fmt, ...) bb_error_msg("%s: " fmt, __func__, ## __VA_ARGS__)
 158 #else
 159 # define DBG(...) ((void)0)
 160 #endif
 161 #define DBG_OPTION_PARSING 0
 162
 163
 164 #define block_buf bb_common_bufsiz1
 165 #define INIT_G() do { setup_common_bufsiz(); } while (0)
 166
 167
 168 #if ENABLE_FEATURE_TAR_CREATE
 169
 170 /*
 171 ** writeTarFile(), writeFileToTarball(), and writeTarHeader() are
 172 ** the only functions that deal with the HardLinkInfo structure.
 173 ** Even these functions use the xxxHardLinkInfo() functions.
 174 */
 175 typedef struct HardLinkInfo {
 176         struct HardLinkInfo *next; /* Next entry in list */
 177         dev_t dev;                 /* Device number */
 178         ino_t ino;                 /* Inode number */
 179 //      short linkCount;           /* (Hard) Link Count */
 180         char name[1];              /* Start of filename (must be last) */
 181 } HardLinkInfo;
 182
 183 /* Some info to be carried along when creating a new tarball */
 184 typedef struct TarBallInfo {
 185         int tarFd;                      /* Open-for-write file descriptor
 186                                          * for the tarball */
 187         int verboseFlag;                /* Whether to print extra stuff or not */
 188         const llist_t *excludeList;     /* List of files to not include */
 189         HardLinkInfo *hlInfoHead;       /* Hard Link Tracking Information */
 190         HardLinkInfo *hlInfo;           /* Hard Link Info for the current file */
 191 //TODO: save only st_dev + st_ino
 192         struct stat tarFileStatBuf;     /* Stat info for the tarball, letting
 193                                          * us know the inode and device that the
 194                                          * tarball lives, so we can avoid trying
 195                                          * to include the tarball into itself */
 196 } TarBallInfo;
 197
 198 /* A nice enum with all the possible tar file content types */
 199 enum {
 200         REGTYPE = '0',          /* regular file */
 201         REGTYPE0 = '\0',        /* regular file (ancient bug compat) */
 202         LNKTYPE = '1',          /* hard link */
 203         SYMTYPE = '2',          /* symbolic link */
 204         CHRTYPE = '3',          /* character special */
 205         BLKTYPE = '4',          /* block special */
 206         DIRTYPE = '5',          /* directory */
 207         FIFOTYPE = '6',         /* FIFO special */
 208         CONTTYPE = '7',         /* reserved */
 209         GNULONGLINK = 'K',      /* GNU long (>100 chars) link name */
 210         GNULONGNAME = 'L',      /* GNU long (>100 chars) file name */
 211 };
 212
 213 /* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */
 214 static void addHardLinkInfo(HardLinkInfo **hlInfoHeadPtr,
 215                                         struct stat *statbuf,
 216                                         const char *fileName)
 217 {
 218         /* Note: hlInfoHeadPtr can never be NULL! */
 219         HardLinkInfo *hlInfo;
 220
 221         hlInfo = xmalloc(sizeof(HardLinkInfo) + strlen(fileName));
 222         hlInfo->next = *hlInfoHeadPtr;
 223         *hlInfoHeadPtr = hlInfo;
 224         hlInfo->dev = statbuf->st_dev;
 225         hlInfo->ino = statbuf->st_ino;
 226 //      hlInfo->linkCount = statbuf->st_nlink;
 227         strcpy(hlInfo->name, fileName);
 228 }
 229
 230 static void freeHardLinkInfo(HardLinkInfo **hlInfoHeadPtr)
 231 {
 232         HardLinkInfo *hlInfo;
 233         HardLinkInfo *hlInfoNext;
 234
 235         if (hlInfoHeadPtr) {
 236                 hlInfo = *hlInfoHeadPtr;
 237                 while (hlInfo) {
 238                         hlInfoNext = hlInfo->next;
 239                         free(hlInfo);
 240                         hlInfo = hlInfoNext;
 241                 }
 242                 *hlInfoHeadPtr = NULL;
 243         }
 244 }
 245
 246 /* Might be faster (and bigger) if the dev/ino were stored in numeric order ;) */
 247 static HardLinkInfo *findHardLinkInfo(HardLinkInfo *hlInfo, struct stat *statbuf)
 248 {
 249         while (hlInfo) {
 250                 if (statbuf->st_ino == hlInfo->ino
 251                  && statbuf->st_dev == hlInfo->dev
 252                 ) {
 253                         DBG("found hardlink:'%s'", hlInfo->name);
 254                         break;
 255                 }
 256                 hlInfo = hlInfo->next;
 257         }
 258         return hlInfo;
 259 }
 260
 261 /* Put an octal string into the specified buffer.
 262  * The number is zero padded and possibly null terminated.
 263  * Stores low-order bits only if whole value does not fit. */
 264 static void putOctal(char *cp, int len, off_t value)
 265 {
 266         char tempBuffer[sizeof(off_t)*3 + 1];
 267         char *tempString = tempBuffer;
 268         int width;
 269
 270         width = sprintf(tempBuffer, "%0*"OFF_FMT"o", len, value);
 271         tempString += (width - len);
 272
 273         /* If string has leading zeroes, we can drop one */
 274         /* and field will have trailing '\0' */
 275         /* (increases chances of compat with other tars) */
 276         if (tempString[0] == '0')
 277                 tempString++;
 278
 279         /* Copy the string to the field */
 280         memcpy(cp, tempString, len);
 281 }
 282 #define PUT_OCTAL(a, b) putOctal((a), sizeof(a), (b))
 283
 284 static void chksum_and_xwrite(int fd, struct tar_header_t* hp)
 285 {
 286         /* POSIX says that checksum is done on unsigned bytes
 287          * (Sun and HP-UX gets it wrong... more details in
 288          * GNU tar source) */
 289         const unsigned char *cp;
 290         int chksum, size;
 291
 292         strcpy(hp->magic, "ustar  ");
 293
 294         /* Calculate and store the checksum (i.e., the sum of all of the bytes of
 295          * the header).  The checksum field must be filled with blanks for the
 296          * calculation.  The checksum field is formatted differently from the
 297          * other fields: it has 6 digits, a null, then a space -- rather than
 298          * digits, followed by a null like the other fields... */
 299         memset(hp->chksum, ' ', sizeof(hp->chksum));
 300         cp = (const unsigned char *) hp;
 301         chksum = 0;
 302         size = sizeof(*hp);
 303         do { chksum += *cp++; } while (--size);
 304         putOctal(hp->chksum, sizeof(hp->chksum)-1, chksum);
 305
 306         /* Now write the header out to disk */
 307         xwrite(fd, hp, sizeof(*hp));
 308 }
 309
 310 #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 311 static void writeLongname(int fd, int type, const char *name, int dir)
 312 {
 313         static const struct {
 314                 char mode[8];             /* 100-107 */
 315                 char uid[8];              /* 108-115 */
 316                 char gid[8];              /* 116-123 */
 317                 char size[12];            /* 124-135 */
 318                 char mtime[12];           /* 136-147 */
 319         } prefilled = {
 320                 "0000000",
 321                 "0000000",
 322                 "0000000",
 323                 "00000000000",
 324                 "00000000000",
 325         };
 326         struct tar_header_t header;
 327         int size;
 328
 329         dir = !!dir; /* normalize: 0/1 */
 330         size = strlen(name) + 1 + dir; /* GNU tar uses strlen+1 */
 331         /* + dir: account for possible '/' */
 332
 333         memset(&header, 0, sizeof(header));
 334         strcpy(header.name, "././@LongLink");
 335         memcpy(header.mode, prefilled.mode, sizeof(prefilled));
 336         PUT_OCTAL(header.size, size);
 337         header.typeflag = type;
 338         chksum_and_xwrite(fd, &header);
 339
 340         /* Write filename[/] and pad the block. */
 341         /* dir=0: writes 'name<NUL>', pads */
 342         /* dir=1: writes 'name', writes '/<NUL>', pads */
 343         dir *= 2;
 344         xwrite(fd, name, size - dir);
 345         xwrite(fd, "/", dir);
 346         size = (-size) & (TAR_BLOCK_SIZE-1);
 347         memset(&header, 0, size);
 348         xwrite(fd, &header, size);
 349 }
 350 #endif
 351
 352 /* Write out a tar header for the specified file/directory/whatever */
 353 static int writeTarHeader(struct TarBallInfo *tbInfo,
 354                 const char *header_name, const char *fileName, struct stat *statbuf)
 355 {
 356         struct tar_header_t header;
 357
 358         memset(&header, 0, sizeof(header));
 359
 360         strncpy(header.name, header_name, sizeof(header.name));
 361
 362         /* POSIX says to mask mode with 07777. */
 363         PUT_OCTAL(header.mode, statbuf->st_mode & 07777);
 364         PUT_OCTAL(header.uid, statbuf->st_uid);
 365         PUT_OCTAL(header.gid, statbuf->st_gid);
 366         memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */
 367         /* users report that files with negative st_mtime cause trouble, so: */
 368         PUT_OCTAL(header.mtime, statbuf->st_mtime >= 0 ? statbuf->st_mtime : 0);
 369
 370         /* Enter the user and group names */
 371         safe_strncpy(header.uname, get_cached_username(statbuf->st_uid), sizeof(header.uname));
 372         safe_strncpy(header.gname, get_cached_groupname(statbuf->st_gid), sizeof(header.gname));
 373
 374         if (tbInfo->hlInfo) {
 375                 /* This is a hard link */
 376                 header.typeflag = LNKTYPE;
 377                 strncpy(header.linkname, tbInfo->hlInfo->name,
 378                                 sizeof(header.linkname));
 379 #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 380                 /* Write out long linkname if needed */
 381                 if (header.linkname[sizeof(header.linkname)-1])
 382                         writeLongname(tbInfo->tarFd, GNULONGLINK,
 383                                         tbInfo->hlInfo->name, 0);
 384 #endif
 385         } else if (S_ISLNK(statbuf->st_mode)) {
 386                 char *lpath = xmalloc_readlink_or_warn(fileName);
 387                 if (!lpath)
 388                         return FALSE;
 389                 header.typeflag = SYMTYPE;
 390                 strncpy(header.linkname, lpath, sizeof(header.linkname));
 391 #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 392                 /* Write out long linkname if needed */
 393                 if (header.linkname[sizeof(header.linkname)-1])
 394                         writeLongname(tbInfo->tarFd, GNULONGLINK, lpath, 0);
 395 #else
 396                 /* If it is larger than 100 bytes, bail out */
 397                 if (header.linkname[sizeof(header.linkname)-1]) {
 398                         free(lpath);
 399                         bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
 400                         return FALSE;
 401                 }
 402 #endif
 403                 free(lpath);
 404         } else if (S_ISDIR(statbuf->st_mode)) {
 405                 header.typeflag = DIRTYPE;
 406                 /* Append '/' only if there is a space for it */
 407                 if (!header.name[sizeof(header.name)-1])
 408                         header.name[strlen(header.name)] = '/';
 409         } else if (S_ISCHR(statbuf->st_mode)) {
 410                 header.typeflag = CHRTYPE;
 411                 PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
 412                 PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
 413         } else if (S_ISBLK(statbuf->st_mode)) {
 414                 header.typeflag = BLKTYPE;
 415                 PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
 416                 PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
 417         } else if (S_ISFIFO(statbuf->st_mode)) {
 418                 header.typeflag = FIFOTYPE;
 419         } else if (S_ISREG(statbuf->st_mode)) {
 420                 /* header.size field is 12 bytes long */
 421                 /* Does octal-encoded size fit? */
 422                 uoff_t filesize = statbuf->st_size;
 423                 if (sizeof(filesize) <= 4
 424                  || filesize <= (uoff_t)0777777777777LL
 425                 ) {
 426                         PUT_OCTAL(header.size, filesize);
 427                 }
 428                 /* Does base256-encoded size fit?
 429                  * It always does unless off_t is wider than 64 bits.
 430                  */
 431                 else if (ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 432 #if ULLONG_MAX > 0xffffffffffffffffLL /* 2^64-1 */
 433                  && (filesize <= 0x3fffffffffffffffffffffffLL)
 434 #endif
 435                 ) {
 436                         /* GNU tar uses "base-256 encoding" for very large numbers.
 437                          * Encoding is binary, with highest bit always set as a marker
 438                          * and sign in next-highest bit:
 439                          * 80 00 .. 00 - zero
 440                          * bf ff .. ff - largest positive number
 441                          * ff ff .. ff - minus 1
 442                          * c0 00 .. 00 - smallest negative number
 443                          */
 444                         char *p8 = header.size + sizeof(header.size);
 445                         do {
 446                                 *--p8 = (uint8_t)filesize;
 447                                 filesize >>= 8;
 448                         } while (p8 != header.size);
 449                         *p8 |= 0x80;
 450                 } else {
 451                         bb_error_msg_and_die("can't store file '%s' "
 452                                 "of size %"OFF_FMT"u, aborting",
 453                                 fileName, statbuf->st_size);
 454                 }
 455                 header.typeflag = REGTYPE;
 456         } else {
 457                 bb_error_msg("%s: unknown file type", fileName);
 458                 return FALSE;
 459         }
 460
 461 #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 462         /* Write out long name if needed */
 463         /* (we, like GNU tar, output long linkname *before* long name) */
 464         if (header.name[sizeof(header.name)-1])
 465                 writeLongname(tbInfo->tarFd, GNULONGNAME,
 466                                 header_name, S_ISDIR(statbuf->st_mode));
 467 #endif
 468
 469         /* Now write the header out to disk */
 470         chksum_and_xwrite(tbInfo->tarFd, &header);
 471
 472         /* Now do the verbose thing (or not) */
 473         if (tbInfo->verboseFlag) {
 474                 FILE *vbFd = stdout;
 475
 476                 /* If archive goes to stdout, verbose goes to stderr */
 477                 if (tbInfo->tarFd == STDOUT_FILENO)
 478                         vbFd = stderr;
 479                 /* GNU "tar cvvf" prints "extended" listing a-la "ls -l" */
 480                 /* We don't have such excesses here: for us "v" == "vv" */
 481                 /* '/' is probably a GNUism */
 482                 fprintf(vbFd, "%s%s\n", header_name,
 483                                 S_ISDIR(statbuf->st_mode) ? "/" : "");
 484         }
 485
 486         return TRUE;
 487 }
 488
 489 #if ENABLE_FEATURE_TAR_FROM
 490 static int exclude_file(const llist_t *excluded_files, const char *file)
 491 {
 492         while (excluded_files) {
 493                 if (excluded_files->data[0] == '/') {
 494                         if (fnmatch(excluded_files->data, file,
 495                                         FNM_PATHNAME | FNM_LEADING_DIR) == 0)
 496                                 return 1;
 497                 } else {
 498                         const char *p;
 499
 500                         for (p = file; p[0] != '\0'; p++) {
 501                                 if ((p == file || p[-1] == '/')
 502                                  && p[0] != '/'
 503                                  && fnmatch(excluded_files->data, p,
 504                                                 FNM_PATHNAME | FNM_LEADING_DIR) == 0
 505                                 ) {
 506                                         return 1;
 507                                 }
 508                         }
 509                 }
 510                 excluded_files = excluded_files->link;
 511         }
 512
 513         return 0;
 514 }
 515 #else
 516 # define exclude_file(excluded_files, file) 0
 517 #endif
 518
 519 static int FAST_FUNC writeFileToTarball(const char *fileName, struct stat *statbuf,
 520                         void *userData, int depth UNUSED_PARAM)
 521 {
 522         struct TarBallInfo *tbInfo = (struct TarBallInfo *) userData;
 523         const char *header_name;
 524         int inputFileFd = -1;
 525
 526         DBG("writeFileToTarball('%s')", fileName);
 527
 528         /* Strip leading '/' and such (must be before memorizing hardlink's name) */
 529         header_name = strip_unsafe_prefix(fileName);
 530
 531         if (header_name[0] == '\0')
 532                 return TRUE;
 533
 534         /* It is against the rules to archive a socket */
 535         if (S_ISSOCK(statbuf->st_mode)) {
 536                 bb_error_msg("%s: socket ignored", fileName);
 537                 return TRUE;
 538         }
 539
 540         /*
 541          * Check to see if we are dealing with a hard link.
 542          * If so -
 543          * Treat the first occurance of a given dev/inode as a file while
 544          * treating any additional occurances as hard links.  This is done
 545          * by adding the file information to the HardLinkInfo linked list.
 546          */
 547         tbInfo->hlInfo = NULL;
 548         if (!S_ISDIR(statbuf->st_mode) && statbuf->st_nlink > 1) {
 549                 DBG("'%s': st_nlink > 1", header_name);
 550                 tbInfo->hlInfo = findHardLinkInfo(tbInfo->hlInfoHead, statbuf);
 551                 if (tbInfo->hlInfo == NULL) {
 552                         DBG("'%s': addHardLinkInfo", header_name);
 553                         addHardLinkInfo(&tbInfo->hlInfoHead, statbuf, header_name);
 554                 }
 555         }
 556
 557         /* It is a bad idea to store the archive we are in the process of creating,
 558          * so check the device and inode to be sure that this particular file isn't
 559          * the new tarball */
 560         if (tbInfo->tarFileStatBuf.st_dev == statbuf->st_dev
 561          && tbInfo->tarFileStatBuf.st_ino == statbuf->st_ino
 562         ) {
 563                 bb_error_msg("%s: file is the archive; skipping", fileName);
 564                 return TRUE;
 565         }
 566
 567         if (exclude_file(tbInfo->excludeList, header_name))
 568                 return SKIP;
 569
 570 #if !ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 571         if (strlen(header_name) >= NAME_SIZE) {
 572                 bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
 573                 return TRUE;
 574         }
 575 #endif
 576
 577         /* Is this a regular file? */
 578         if (tbInfo->hlInfo == NULL && S_ISREG(statbuf->st_mode)) {
 579                 /* open the file we want to archive, and make sure all is well */
 580                 inputFileFd = open_or_warn(fileName, O_RDONLY);
 581                 if (inputFileFd < 0) {
 582                         return FALSE;
 583                 }
 584         }
 585
 586         /* Add an entry to the tarball */
 587         if (writeTarHeader(tbInfo, header_name, fileName, statbuf) == FALSE) {
 588                 return FALSE;
 589         }
 590
 591         /* If it was a regular file, write out the body */
 592         if (inputFileFd >= 0) {
 593                 size_t readSize;
 594                 /* Write the file to the archive. */
 595                 /* We record size into header first, */
 596                 /* and then write out file. If file shrinks in between, */
 597                 /* tar will be corrupted. So we don't allow for that. */
 598                 /* NB: GNU tar 1.16 warns and pads with zeroes */
 599                 /* or even seeks back and updates header */
 600                 bb_copyfd_exact_size(inputFileFd, tbInfo->tarFd, statbuf->st_size);
 601                 ////off_t readSize;
 602                 ////readSize = bb_copyfd_size(inputFileFd, tbInfo->tarFd, statbuf->st_size);
 603                 ////if (readSize != statbuf->st_size && readSize >= 0) {
 604                 ////    bb_error_msg_and_die("short read from %s, aborting", fileName);
 605                 ////}
 606
 607                 /* Check that file did not grow in between? */
 608                 /* if (safe_read(inputFileFd, 1) == 1) warn but continue? */
 609
 610                 close(inputFileFd);
 611
 612                 /* Pad the file up to the tar block size */
 613                 /* (a few tricks here in the name of code size) */
 614                 readSize = (-(int)statbuf->st_size) & (TAR_BLOCK_SIZE-1);
 615                 memset(block_buf, 0, readSize);
 616                 xwrite(tbInfo->tarFd, block_buf, readSize);
 617         }
 618
 619         return TRUE;
 620 }
 621
 622 #if SEAMLESS_COMPRESSION
 623 /* Don't inline: vfork scares gcc and pessimizes code */
 624 static void NOINLINE vfork_compressor(int tar_fd, const char *gzip)
 625 {
 626         pid_t gzipPid;
 627
 628         // On Linux, vfork never unpauses parent early, although standard
 629         // allows for that. Do we want to waste bytes checking for it?
 630 # define WAIT_FOR_CHILD 0
 631         volatile int vfork_exec_errno = 0;
 632         struct fd_pair gzipDataPipe;
 633 # if WAIT_FOR_CHILD
 634         struct fd_pair gzipStatusPipe;
 635         xpiped_pair(gzipStatusPipe);
 636 # endif
 637         xpiped_pair(gzipDataPipe);
 638
 639         signal(SIGPIPE, SIG_IGN); /* we only want EPIPE on errors */
 640
 641         gzipPid = xvfork();
 642
 643         if (gzipPid == 0) {
 644                 /* child */
 645                 /* NB: close _first_, then move fds! */
 646                 close(gzipDataPipe.wr);
 647 # if WAIT_FOR_CHILD
 648                 close(gzipStatusPipe.rd);
 649                 /* gzipStatusPipe.wr will close only on exec -
 650                  * parent waits for this close to happen */
 651                 fcntl(gzipStatusPipe.wr, F_SETFD, FD_CLOEXEC);
 652 # endif
 653                 xmove_fd(gzipDataPipe.rd, 0);
 654                 xmove_fd(tar_fd, 1);
 655                 /* exec gzip/bzip2 program/applet */
 656                 BB_EXECLP(gzip, gzip, "-f", (char *)0);
 657                 vfork_exec_errno = errno;
 658                 _exit(EXIT_FAILURE);
 659         }
 660
 661         /* parent */
 662         xmove_fd(gzipDataPipe.wr, tar_fd);
 663         close(gzipDataPipe.rd);
 664 # if WAIT_FOR_CHILD
 665         close(gzipStatusPipe.wr);
 666         while (1) {
 667                 char buf;
 668                 int n;
 669
 670                 /* Wait until child execs (or fails to) */
 671                 n = full_read(gzipStatusPipe.rd, &buf, 1);
 672                 if (n < 0 /* && errno == EAGAIN */)
 673                         continue;       /* try it again */
 674         }
 675         close(gzipStatusPipe.rd);
 676 # endif
 677         if (vfork_exec_errno) {
 678                 errno = vfork_exec_errno;
 679                 bb_perror_msg_and_die("can't execute '%s'", gzip);
 680         }
 681 }
 682 #endif /* SEAMLESS_COMPRESSION */
 683
 684
 685 #if !SEAMLESS_COMPRESSION
 686 /* Do not pass gzip flag to writeTarFile() */
 687 #define writeTarFile(tar_fd, verboseFlag, recurseFlags, include, exclude, gzip) \
 688         writeTarFile(tar_fd, verboseFlag, recurseFlags, include, exclude)
 689 #endif
 690 /* gcc 4.2.1 inlines it, making code bigger */
 691 static NOINLINE int writeTarFile(int tar_fd, int verboseFlag,
 692         int recurseFlags, const llist_t *include,
 693         const llist_t *exclude, const char *gzip)
 694 {
 695         int errorFlag = FALSE;
 696         struct TarBallInfo tbInfo;
 697
 698         tbInfo.hlInfoHead = NULL;
 699         tbInfo.tarFd = tar_fd;
 700         tbInfo.verboseFlag = verboseFlag;
 701
 702         /* Store the stat info for the tarball's file, so
 703          * can avoid including the tarball into itself....  */
 704         xfstat(tbInfo.tarFd, &tbInfo.tarFileStatBuf, "can't stat tar file");
 705
 706 #if SEAMLESS_COMPRESSION
 707         if (gzip)
 708                 vfork_compressor(tbInfo.tarFd, gzip);
 709 #endif
 710
 711         tbInfo.excludeList = exclude;
 712
 713         /* Read the directory/files and iterate over them one at a time */
 714         while (include) {
 715                 if (!recursive_action(include->data, recurseFlags,
 716                                 writeFileToTarball, writeFileToTarball, &tbInfo, 0)
 717                 ) {
 718                         errorFlag = TRUE;
 719                 }
 720                 include = include->link;
 721         }
 722         /* Write two empty blocks to the end of the archive */
 723         memset(block_buf, 0, 2*TAR_BLOCK_SIZE);
 724         xwrite(tbInfo.tarFd, block_buf, 2*TAR_BLOCK_SIZE);
 725
 726         /* To be pedantically correct, we would check if the tarball
 727          * is smaller than 20 tar blocks, and pad it if it was smaller,
 728          * but that isn't necessary for GNU tar interoperability, and
 729          * so is considered a waste of space */
 730
 731         /* Close so the child process (if any) will exit */
 732         close(tbInfo.tarFd);
 733
 734         /* Hang up the tools, close up shop, head home */
 735         if (ENABLE_FEATURE_CLEAN_UP)
 736                 freeHardLinkInfo(&tbInfo.hlInfoHead);
 737
 738         if (errorFlag)
 739                 bb_error_msg("error exit delayed from previous errors");
 740
 741 #if SEAMLESS_COMPRESSION
 742         if (gzip) {
 743                 int status;
 744                 if (safe_waitpid(-1, &status, 0) == -1)
 745                         bb_perror_msg("waitpid");
 746                 else if (!WIFEXITED(status) || WEXITSTATUS(status))
 747                         /* gzip was killed or has exited with nonzero! */
 748                         errorFlag = TRUE;
 749         }
 750 #endif
 751         return errorFlag;
 752 }
 753 #else /* !FEATURE_TAR_CREATE */
 754 # define writeTarFile(...) 0
 755 #endif
 756
 757 #if ENABLE_FEATURE_TAR_FROM
 758 static llist_t *append_file_list_to_list(llist_t *list)
 759 {
 760         FILE *src_stream;
 761         char *line;
 762         llist_t *newlist = NULL;
 763
 764         while (list) {
 765                 src_stream = xfopen_stdin(llist_pop(&list));
 766                 while ((line = xmalloc_fgetline(src_stream)) != NULL) {
 767                         /* kill trailing '/' unless the string is just "/" */
 768                         char *cp = last_char_is(line, '/');
 769                         if (cp > line)
 770                                 *cp = '\0';
 771                         llist_add_to_end(&newlist, line);
 772                 }
 773                 fclose(src_stream);
 774         }
 775         return newlist;
 776 }
 777 #endif
 778
 779 //usage:#define tar_trivial_usage
 780 //usage:        "-[" IF_FEATURE_TAR_CREATE("c") "xt"
 781 //usage:        IF_FEATURE_SEAMLESS_Z("Z")
 782 //usage:        IF_FEATURE_SEAMLESS_GZ("z")
 783 //usage:        IF_FEATURE_SEAMLESS_XZ("J")
 784 //usage:        IF_FEATURE_SEAMLESS_BZ2("j")
 785 //usage:        IF_FEATURE_SEAMLESS_LZMA("a")
 786 //usage:        IF_FEATURE_TAR_CREATE("h")
 787 //usage:        IF_FEATURE_TAR_NOPRESERVE_TIME("m")
 788 //usage:        "vO] "
 789 //usage:        IF_FEATURE_TAR_FROM("[-X FILE] [-T FILE] ")
 790 //usage:        "[-f TARFILE] [-C DIR] [FILE]..."
 791 //usage:#define tar_full_usage "\n\n"
 792 //usage:        IF_FEATURE_TAR_CREATE("Create, extract, ")
 793 //usage:        IF_NOT_FEATURE_TAR_CREATE("Extract ")
 794 //usage:        "or list files from a tar file\n"
 795 //usage:     "\nOperation:"
 796 //usage:        IF_FEATURE_TAR_CREATE(
 797 //usage:     "\n        c       Create"
 798 //usage:        )
 799 //usage:     "\n        x       Extract"
 800 //usage:     "\n        t       List"
 801 //usage:     "\n        f       Name of TARFILE ('-' for stdin/out)"
 802 //usage:     "\n        C       Change to DIR before operation"
 803 //usage:     "\n        v       Verbose"
 804 //usage:        IF_FEATURE_SEAMLESS_Z(
 805 //usage:     "\n        Z       (De)compress using compress"
 806 //usage:        )
 807 //usage:        IF_FEATURE_SEAMLESS_GZ(
 808 //usage:     "\n        z       (De)compress using gzip"
 809 //usage:        )
 810 //usage:        IF_FEATURE_SEAMLESS_XZ(
 811 //usage:     "\n        J       (De)compress using xz"
 812 //usage:        )
 813 //usage:        IF_FEATURE_SEAMLESS_BZ2(
 814 //usage:     "\n        j       (De)compress using bzip2"
 815 //usage:        )
 816 //usage:        IF_FEATURE_SEAMLESS_LZMA(
 817 //usage:     "\n        a       (De)compress using lzma"
 818 //usage:        )
 819 //usage:     "\n        O       Extract to stdout"
 820 //usage:        IF_FEATURE_TAR_CREATE(
 821 //usage:     "\n        h       Follow symlinks"
 822 //usage:        )
 823 //usage:        IF_FEATURE_TAR_NOPRESERVE_TIME(
 824 //usage:     "\n        m       Don't restore mtime"
 825 //usage:        )
 826 //usage:        IF_FEATURE_TAR_FROM(
 827 //usage:        IF_FEATURE_TAR_LONG_OPTIONS(
 828 //usage:     "\n        exclude File to exclude"
 829 //usage:        )
 830 //usage:     "\n        X       File with names to exclude"
 831 //usage:     "\n        T       File with names to include"
 832 //usage:        )
 833 //usage:
 834 //usage:#define tar_example_usage
 835 //usage:       "$ zcat /tmp/tarball.tar.gz | tar -xf -\n"
 836 //usage:       "$ tar -cf /tmp/tarball.tar /usr/local\n"
 837
 838 // Supported but aren't in --help:
 839 //      o       no-same-owner
 840 //      p       same-permissions
 841 //      k       keep-old
 842 //      no-recursion
 843 //      numeric-owner
 844 //      no-same-permissions
 845 //      overwrite
 846 //IF_FEATURE_TAR_TO_COMMAND(
 847 //      to-command
 848 //)
 849
 850 enum {
 851         OPTBIT_KEEP_OLD = 8,
 852         IF_FEATURE_TAR_CREATE(   OPTBIT_CREATE      ,)
 853         IF_FEATURE_TAR_CREATE(   OPTBIT_DEREFERENCE ,)
 854         IF_FEATURE_SEAMLESS_BZ2( OPTBIT_BZIP2       ,)
 855         IF_FEATURE_SEAMLESS_LZMA(OPTBIT_LZMA        ,)
 856         IF_FEATURE_TAR_FROM(     OPTBIT_INCLUDE_FROM,)
 857         IF_FEATURE_TAR_FROM(     OPTBIT_EXCLUDE_FROM,)
 858         IF_FEATURE_SEAMLESS_GZ(  OPTBIT_GZIP        ,)
 859         IF_FEATURE_SEAMLESS_XZ(  OPTBIT_XZ          ,) // 16th bit
 860         IF_FEATURE_SEAMLESS_Z(   OPTBIT_COMPRESS    ,)
 861         IF_FEATURE_TAR_NOPRESERVE_TIME(OPTBIT_NOPRESERVE_TIME,)
 862 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
 863         OPTBIT_STRIP_COMPONENTS,
 864         OPTBIT_NORECURSION,
 865         IF_FEATURE_TAR_TO_COMMAND(OPTBIT_2COMMAND   ,)
 866         OPTBIT_NUMERIC_OWNER,
 867         OPTBIT_NOPRESERVE_PERM,
 868         OPTBIT_OVERWRITE,
 869 #endif
 870         OPT_TEST         = 1 << 0, // t
 871         OPT_EXTRACT      = 1 << 1, // x
 872         OPT_BASEDIR      = 1 << 2, // C
 873         OPT_TARNAME      = 1 << 3, // f
 874         OPT_2STDOUT      = 1 << 4, // O
 875         OPT_NOPRESERVE_OWNER = 1 << 5, // o == no-same-owner
 876         OPT_P            = 1 << 6, // p
 877         OPT_VERBOSE      = 1 << 7, // v
 878         OPT_KEEP_OLD     = 1 << 8, // k
 879         OPT_CREATE       = IF_FEATURE_TAR_CREATE(   (1 << OPTBIT_CREATE      )) + 0, // c
 880         OPT_DEREFERENCE  = IF_FEATURE_TAR_CREATE(   (1 << OPTBIT_DEREFERENCE )) + 0, // h
 881         OPT_BZIP2        = IF_FEATURE_SEAMLESS_BZ2( (1 << OPTBIT_BZIP2       )) + 0, // j
 882         OPT_LZMA         = IF_FEATURE_SEAMLESS_LZMA((1 << OPTBIT_LZMA        )) + 0, // a
 883         OPT_INCLUDE_FROM = IF_FEATURE_TAR_FROM(     (1 << OPTBIT_INCLUDE_FROM)) + 0, // T
 884         OPT_EXCLUDE_FROM = IF_FEATURE_TAR_FROM(     (1 << OPTBIT_EXCLUDE_FROM)) + 0, // X
 885         OPT_GZIP         = IF_FEATURE_SEAMLESS_GZ(  (1 << OPTBIT_GZIP        )) + 0, // z
 886         OPT_XZ           = IF_FEATURE_SEAMLESS_XZ(  (1 << OPTBIT_XZ          )) + 0, // J
 887         OPT_COMPRESS     = IF_FEATURE_SEAMLESS_Z(   (1 << OPTBIT_COMPRESS    )) + 0, // Z
 888         OPT_NOPRESERVE_TIME  = IF_FEATURE_TAR_NOPRESERVE_TIME((1 << OPTBIT_NOPRESERVE_TIME)) + 0, // m
 889         OPT_STRIP_COMPONENTS = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_STRIP_COMPONENTS)) + 0, // strip-components
 890         OPT_NORECURSION      = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NORECURSION    )) + 0, // no-recursion
 891         OPT_2COMMAND         = IF_FEATURE_TAR_TO_COMMAND(  (1 << OPTBIT_2COMMAND       )) + 0, // to-command
 892         OPT_NUMERIC_OWNER    = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NUMERIC_OWNER  )) + 0, // numeric-owner
 893         OPT_NOPRESERVE_PERM  = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NOPRESERVE_PERM)) + 0, // no-same-permissions
 894         OPT_OVERWRITE        = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_OVERWRITE      )) + 0, // overwrite
 895
 896         OPT_ANY_COMPRESS = (OPT_BZIP2 | OPT_LZMA | OPT_GZIP | OPT_XZ | OPT_COMPRESS),
 897 };
 898 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
 899 static const char tar_longopts[] ALIGN1 =
 900         "list\0"                No_argument       "t"
 901         "extract\0"             No_argument       "x"
 902         "directory\0"           Required_argument "C"
 903         "file\0"                Required_argument "f"
 904         "to-stdout\0"           No_argument       "O"
 905         /* do not restore owner */
 906         /* Note: GNU tar handles 'o' as no-same-owner only on extract,
 907          * on create, 'o' is --old-archive. We do not support --old-archive. */
 908         "no-same-owner\0"       No_argument       "o"
 909         "same-permissions\0"    No_argument       "p"
 910         "verbose\0"             No_argument       "v"
 911         "keep-old\0"            No_argument       "k"
 912 # if ENABLE_FEATURE_TAR_CREATE
 913         "create\0"              No_argument       "c"
 914         "dereference\0"         No_argument       "h"
 915 # endif
 916 # if ENABLE_FEATURE_SEAMLESS_BZ2
 917         "bzip2\0"               No_argument       "j"
 918 # endif
 919 # if ENABLE_FEATURE_SEAMLESS_LZMA
 920         "lzma\0"                No_argument       "a"
 921 # endif
 922 # if ENABLE_FEATURE_TAR_FROM
 923         "files-from\0"          Required_argument "T"
 924         "exclude-from\0"        Required_argument "X"
 925 # endif
 926 # if ENABLE_FEATURE_SEAMLESS_GZ
 927         "gzip\0"                No_argument       "z"
 928 # endif
 929 # if ENABLE_FEATURE_SEAMLESS_XZ
 930         "xz\0"                  No_argument       "J"
 931 # endif
 932 # if ENABLE_FEATURE_SEAMLESS_Z
 933         "compress\0"            No_argument       "Z"
 934 # endif
 935 # if ENABLE_FEATURE_TAR_NOPRESERVE_TIME
 936         "touch\0"               No_argument       "m"
 937 # endif
 938         "strip-components\0"    Required_argument "\xf9"
 939         "no-recursion\0"        No_argument       "\xfa"
 940 # if ENABLE_FEATURE_TAR_TO_COMMAND
 941         "to-command\0"          Required_argument "\xfb"
 942 # endif
 943         /* use numeric uid/gid from tar header, not textual */
 944         "numeric-owner\0"       No_argument       "\xfc"
 945         /* do not restore mode */
 946         "no-same-permissions\0" No_argument       "\xfd"
 947         /* on unpack, open with O_TRUNC and !O_EXCL */
 948         "overwrite\0"           No_argument       "\xfe"
 949         /* --exclude takes next bit position in option mask, */
 950         /* therefore we have to put it _after_ --no-same-permissions */
 951 # if ENABLE_FEATURE_TAR_FROM
 952         "exclude\0"             Required_argument "\xff"
 953 # endif
 954         ;
 955 #endif
 956
 957 int tar_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 958 int tar_main(int argc UNUSED_PARAM, char **argv)
 959 {
 960         archive_handle_t *tar_handle;
 961         char *base_dir = NULL;
 962         const char *tar_filename = "-";
 963         unsigned opt;
 964         int verboseFlag = 0;
 965 #if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
 966         llist_t *excludes = NULL;
 967 #endif
 968         INIT_G();
 969
 970         /* Initialise default values */
 971         tar_handle = init_handle();
 972         tar_handle->ah_flags = ARCHIVE_CREATE_LEADING_DIRS
 973                              | ARCHIVE_RESTORE_DATE
 974                              | ARCHIVE_UNLINK_OLD;
 975
 976         /* Apparently only root's tar preserves perms (see bug 3844) */
 977         if (getuid() != 0)
 978                 tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_PERM;
 979
 980         /* Prepend '-' to the first argument if required */
 981         opt_complementary = "--:" // first arg is options
 982                 "tt:vv:" // count -t,-v
 983 #if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
 984                 "\xff::" // --exclude=PATTERN is a list
 985 #endif
 986                 IF_FEATURE_TAR_CREATE("c:") "t:x:" // at least one of these is reqd
 987                 IF_FEATURE_TAR_CREATE("c--tx:t--cx:x--ct") // mutually exclusive
 988                 IF_NOT_FEATURE_TAR_CREATE("t--x:x--t") // mutually exclusive
 989 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
 990                 ":\xf9+" // --strip-components=NUM
 991 #endif
 992         ;
 993 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
 994         applet_long_options = tar_longopts;
 995 #endif
 996 #if ENABLE_DESKTOP
 997         /* Lie to buildroot when it starts asking stupid questions. */
 998         if (argv[1] && strcmp(argv[1], "--version") == 0) {
 999                 // Output of 'tar --version' examples:
1000                 // tar (GNU tar) 1.15.1
1001                 // tar (GNU tar) 1.25
1002                 // bsdtar 2.8.3 - libarchive 2.8.3
1003                 puts("tar (busybox) " BB_VER);
1004                 return 0;
1005         }
1006         if (argv[1] && argv[1][0] != '-') {
1007                 /* Compat:
1008                  * 1st argument without dash handles options with parameters
1009                  * differently from dashed one: it takes *next argv[i]*
1010                  * as paramenter even if there are more chars in 1st argument:
1011                  *  "tar fx TARFILE" - "x" is not taken as f's param
1012                  *  but is interpreted as -x option
1013                  *  "tar -xf TARFILE" - dashed equivalent of the above
1014                  *  "tar -fx ..." - "x" is taken as f's param
1015                  * getopt32 wouldn't handle 1st command correctly.
1016                  * Unfortunately, people do use such commands.
1017                  * We massage argv[1] to work around it by moving 'f'
1018                  * to the end of the string.
1019                  * More contrived "tar fCx TARFILE DIR" still fails,
1020                  * but such commands are much less likely to be used.
1021                  */
1022                 char *f = strchr(argv[1], 'f');
1023                 if (f) {
1024                         while (f[1] != '\0') {
1025                                 *f = f[1];
1026                                 f++;
1027                         }
1028                         *f = 'f';
1029                 }
1030         }
1031 #endif
1032         opt = getopt32(argv,
1033                 "txC:f:Oopvk"
1034                 IF_FEATURE_TAR_CREATE(   "ch"    )
1035                 IF_FEATURE_SEAMLESS_BZ2( "j"     )
1036                 IF_FEATURE_SEAMLESS_LZMA("a"     )
1037                 IF_FEATURE_TAR_FROM(     "T:*X:*")
1038                 IF_FEATURE_SEAMLESS_GZ(  "z"     )
1039                 IF_FEATURE_SEAMLESS_XZ(  "J"     )
1040                 IF_FEATURE_SEAMLESS_Z(   "Z"     )
1041                 IF_FEATURE_TAR_NOPRESERVE_TIME("m")
1042                 IF_FEATURE_TAR_LONG_OPTIONS("\xf9:") // --strip-components
1043                 , &base_dir // -C dir
1044                 , &tar_filename // -f filename
1045                 IF_FEATURE_TAR_FROM(, &(tar_handle->accept)) // T
1046                 IF_FEATURE_TAR_FROM(, &(tar_handle->reject)) // X
1047 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
1048                 , &tar_handle->tar__strip_components // --strip-components
1049 #endif
1050                 IF_FEATURE_TAR_TO_COMMAND(, &(tar_handle->tar__to_command)) // --to-command
1051 #if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
1052                 , &excludes // --exclude
1053 #endif
1054                 , &verboseFlag // combined count for -t and -v
1055                 , &verboseFlag // combined count for -t and -v
1056                 );
1057 #if DBG_OPTION_PARSING
1058         bb_error_msg("opt: 0x%08x", opt);
1059 # define showopt(o) bb_error_msg("opt & %s(%x): %x", #o, o, opt & o);
1060         showopt(OPT_TEST            );
1061         showopt(OPT_EXTRACT         );
1062         showopt(OPT_BASEDIR         );
1063         showopt(OPT_TARNAME         );
1064         showopt(OPT_2STDOUT         );
1065         showopt(OPT_NOPRESERVE_OWNER);
1066         showopt(OPT_P               );
1067         showopt(OPT_VERBOSE         );
1068         showopt(OPT_KEEP_OLD        );
1069         showopt(OPT_CREATE          );
1070         showopt(OPT_DEREFERENCE     );
1071         showopt(OPT_BZIP2           );
1072         showopt(OPT_LZMA            );
1073         showopt(OPT_INCLUDE_FROM    );
1074         showopt(OPT_EXCLUDE_FROM    );
1075         showopt(OPT_GZIP            );
1076         showopt(OPT_XZ              );
1077         showopt(OPT_COMPRESS        );
1078         showopt(OPT_NOPRESERVE_TIME );
1079         showopt(OPT_STRIP_COMPONENTS);
1080         showopt(OPT_NORECURSION     );
1081         showopt(OPT_2COMMAND        );
1082         showopt(OPT_NUMERIC_OWNER   );
1083         showopt(OPT_NOPRESERVE_PERM );
1084         showopt(OPT_OVERWRITE       );
1085         showopt(OPT_ANY_COMPRESS    );
1086         bb_error_msg("base_dir:'%s'", base_dir);
1087         bb_error_msg("tar_filename:'%s'", tar_filename);
1088         bb_error_msg("verboseFlag:%d", verboseFlag);
1089         bb_error_msg("tar_handle->tar__to_command:'%s'", tar_handle->tar__to_command);
1090         bb_error_msg("tar_handle->tar__strip_components:%u", tar_handle->tar__strip_components);
1091         return 0;
1092 # undef showopt
1093 #endif
1094         argv += optind;
1095
1096         if (verboseFlag)
1097                 tar_handle->action_header = header_verbose_list;
1098         if (verboseFlag == 1)
1099                 tar_handle->action_header = header_list;
1100
1101         if (opt & OPT_EXTRACT)
1102                 tar_handle->action_data = data_extract_all;
1103
1104         if (opt & OPT_2STDOUT)
1105                 tar_handle->action_data = data_extract_to_stdout;
1106
1107         if (opt & OPT_2COMMAND) {
1108                 putenv((char*)"TAR_FILETYPE=f");
1109                 signal(SIGPIPE, SIG_IGN);
1110                 tar_handle->action_data = data_extract_to_command;
1111                 IF_FEATURE_TAR_TO_COMMAND(tar_handle->tar__to_command_shell = xstrdup(get_shell_name());)
1112         }
1113
1114         if (opt & OPT_KEEP_OLD)
1115                 tar_handle->ah_flags &= ~ARCHIVE_UNLINK_OLD;
1116
1117         if (opt & OPT_NUMERIC_OWNER)
1118                 tar_handle->ah_flags |= ARCHIVE_NUMERIC_OWNER;
1119
1120         if (opt & OPT_NOPRESERVE_OWNER)
1121                 tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_OWNER;
1122
1123         if (opt & OPT_NOPRESERVE_PERM)
1124                 tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_PERM;
1125
1126         if (opt & OPT_OVERWRITE) {
1127                 tar_handle->ah_flags &= ~ARCHIVE_UNLINK_OLD;
1128                 tar_handle->ah_flags |= ARCHIVE_O_TRUNC;
1129         }
1130
1131         if (opt & OPT_NOPRESERVE_TIME)
1132                 tar_handle->ah_flags &= ~ARCHIVE_RESTORE_DATE;
1133
1134 #if ENABLE_FEATURE_TAR_FROM
1135         tar_handle->reject = append_file_list_to_list(tar_handle->reject);
1136 # if ENABLE_FEATURE_TAR_LONG_OPTIONS
1137         /* Append excludes to reject */
1138         while (excludes) {
1139                 llist_t *next = excludes->link;
1140                 excludes->link = tar_handle->reject;
1141                 tar_handle->reject = excludes;
1142                 excludes = next;
1143         }
1144 # endif
1145         tar_handle->accept = append_file_list_to_list(tar_handle->accept);
1146 #endif
1147
1148         /* Setup an array of filenames to work with */
1149         /* TODO: This is the same as in ar, make a separate function? */
1150         while (*argv) {
1151                 /* kill trailing '/' unless the string is just "/" */
1152                 char *cp = last_char_is(*argv, '/');
1153                 if (cp > *argv)
1154                         *cp = '\0';
1155                 llist_add_to_end(&tar_handle->accept, *argv);
1156                 argv++;
1157         }
1158
1159         if (tar_handle->accept || tar_handle->reject)
1160                 tar_handle->filter = filter_accept_reject_list;
1161
1162         /* Open the tar file */
1163         {
1164                 int tar_fd = STDIN_FILENO;
1165                 int flags = O_RDONLY;
1166
1167                 if (opt & OPT_CREATE) {
1168                         /* Make sure there is at least one file to tar up */
1169                         if (tar_handle->accept == NULL)
1170                                 bb_error_msg_and_die("empty archive");
1171
1172                         tar_fd = STDOUT_FILENO;
1173                         /* Mimicking GNU tar 1.15.1: */
1174                         flags = O_WRONLY | O_CREAT | O_TRUNC;
1175                 }
1176
1177                 if (LONE_DASH(tar_filename)) {
1178                         tar_handle->src_fd = tar_fd;
1179                         tar_handle->seek = seek_by_read;
1180                 } else {
1181                         if (ENABLE_FEATURE_TAR_AUTODETECT
1182                          && flags == O_RDONLY
1183                          && !(opt & OPT_ANY_COMPRESS)
1184                         ) {
1185                                 tar_handle->src_fd = open_zipped(tar_filename, /*fail_if_not_compressed:*/ 0);
1186                                 if (tar_handle->src_fd < 0)
1187                                         bb_perror_msg_and_die("can't open '%s'", tar_filename);
1188                         } else {
1189                                 tar_handle->src_fd = xopen(tar_filename, flags);
1190                         }
1191                 }
1192         }
1193
1194         if (base_dir)
1195                 xchdir(base_dir);
1196
1197         //if (SEAMLESS_COMPRESSION)
1198         //      /* We need to know whether child (gzip/bzip/etc) exits abnormally */
1199         //      signal(SIGCHLD, check_errors_in_children);
1200
1201 #if ENABLE_FEATURE_TAR_CREATE
1202         /* Create an archive */
1203         if (opt & OPT_CREATE) {
1204 # if SEAMLESS_COMPRESSION
1205                 const char *zipMode = NULL;
1206                 if (opt & OPT_COMPRESS)
1207                         zipMode = "compress";
1208                 if (opt & OPT_GZIP)
1209                         zipMode = "gzip";
1210                 if (opt & OPT_BZIP2)
1211                         zipMode = "bzip2";
1212                 if (opt & OPT_LZMA)
1213                         zipMode = "lzma";
1214                 if (opt & OPT_XZ)
1215                         zipMode = "xz";
1216 # endif
1217                 /* NB: writeTarFile() closes tar_handle->src_fd */
1218                 return writeTarFile(tar_handle->src_fd, verboseFlag,
1219                                 (opt & OPT_DEREFERENCE ? ACTION_FOLLOWLINKS : 0)
1220                                 | (opt & OPT_NORECURSION ? 0 : ACTION_RECURSE),
1221                                 tar_handle->accept,
1222                                 tar_handle->reject, zipMode);
1223         }
1224 #endif
1225
1226         if (opt & OPT_ANY_COMPRESS) {
1227                 USE_FOR_MMU(IF_DESKTOP(long long) int FAST_FUNC (*xformer)(transformer_state_t *xstate);)
1228                 USE_FOR_NOMMU(const char *xformer_prog;)
1229
1230                 if (opt & OPT_COMPRESS)
1231                         USE_FOR_MMU(xformer = unpack_Z_stream;)
1232                         USE_FOR_NOMMU(xformer_prog = "uncompress";)
1233                 if (opt & OPT_GZIP)
1234                         USE_FOR_MMU(xformer = unpack_gz_stream;)
1235                         USE_FOR_NOMMU(xformer_prog = "gunzip";)
1236                 if (opt & OPT_BZIP2)
1237                         USE_FOR_MMU(xformer = unpack_bz2_stream;)
1238                         USE_FOR_NOMMU(xformer_prog = "bunzip2";)
1239                 if (opt & OPT_LZMA)
1240                         USE_FOR_MMU(xformer = unpack_lzma_stream;)
1241                         USE_FOR_NOMMU(xformer_prog = "unlzma";)
1242                 if (opt & OPT_XZ)
1243                         USE_FOR_MMU(xformer = unpack_xz_stream;)
1244                         USE_FOR_NOMMU(xformer_prog = "unxz";)
1245
1246                 fork_transformer_with_sig(tar_handle->src_fd, xformer, xformer_prog);
1247                 /* Can't lseek over pipes */
1248                 tar_handle->seek = seek_by_read;
1249                 /*tar_handle->offset = 0; - already is */
1250         }
1251
1252         /* Zero processed headers (== empty file) is not a valid tarball.
1253          * We (ab)use bb_got_signal as exitcode here,
1254          * because check_errors_in_children() uses _it_ as error indicator.
1255          */
1256         bb_got_signal = EXIT_FAILURE;
1257
1258         while (get_header_tar(tar_handle) == EXIT_SUCCESS)
1259                 bb_got_signal = EXIT_SUCCESS; /* saw at least one header, good */
1260
1261         /* Check that every file that should have been extracted was */
1262         while (tar_handle->accept) {
1263                 if (!find_list_entry(tar_handle->reject, tar_handle->accept->data)
1264                  && !find_list_entry(tar_handle->passed, tar_handle->accept->data)
1265                 ) {
1266                         bb_error_msg_and_die("%s: not found in archive",
1267                                 tar_handle->accept->data);
1268                 }
1269                 tar_handle->accept = tar_handle->accept->link;
1270         }
1271         if (ENABLE_FEATURE_CLEAN_UP /* && tar_handle->src_fd != STDIN_FILENO */)
1272                 close(tar_handle->src_fd);
1273
1274         if (SEAMLESS_COMPRESSION || OPT_COMPRESS) {
1275                 /* Set bb_got_signal to 1 if a child died with !0 exitcode */
1276                 check_errors_in_children(0);
1277         }
1278
1279         return bb_got_signal;
1280 }