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 (40 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 null 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         static const struct {
 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         } prefilled = {
 293                 "0000000",
 294                 "0000000",
 295                 "0000000",
 296                 "00000000000",
 297                 "00000000000",
 298         };
 299         struct tar_header_t header;
 300         int size;
 301
 302         dir = !!dir; /* normalize: 0/1 */
 303         size = strlen(name) + 1 + dir; /* GNU tar uses strlen+1 */
 304         /* + dir: account for possible '/' */
 305
 306         memset(&header, 0, sizeof(header));
 307         strcpy(header.name, "././@LongLink");
 308         memcpy(header.mode, prefilled.mode, sizeof(prefilled));
 309         PUT_OCTAL(header.size, size);
 310         header.typeflag = type;
 311         chksum_and_xwrite(fd, &header);
 312
 313         /* Write filename[/] and pad the block. */
 314         /* dir=0: writes 'name<NUL>', pads */
 315         /* dir=1: writes 'name', writes '/<NUL>', pads */
 316         dir *= 2;
 317         xwrite(fd, name, size - dir);
 318         xwrite(fd, "/", dir);
 319         size = (-size) & (TAR_BLOCK_SIZE-1);
 320         memset(&header, 0, size);
 321         xwrite(fd, &header, size);
 322 }
 323 # endif
 324
 325 /* Write out a tar header for the specified file/directory/whatever */
 326 static int writeTarHeader(struct TarBallInfo *tbInfo,
 327                 const char *header_name, const char *fileName, struct stat *statbuf)
 328 {
 329         struct tar_header_t header;
 330
 331         memset(&header, 0, sizeof(header));
 332
 333         strncpy(header.name, header_name, sizeof(header.name));
 334
 335         /* POSIX says to mask mode with 07777. */
 336         PUT_OCTAL(header.mode, statbuf->st_mode & 07777);
 337         PUT_OCTAL(header.uid, statbuf->st_uid);
 338         PUT_OCTAL(header.gid, statbuf->st_gid);
 339         memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */
 340         /* users report that files with negative st_mtime cause trouble, so: */
 341         PUT_OCTAL(header.mtime, statbuf->st_mtime >= 0 ? statbuf->st_mtime : 0);
 342
 343         /* Enter the user and group names */
 344         safe_strncpy(header.uname, get_cached_username(statbuf->st_uid), sizeof(header.uname));
 345         safe_strncpy(header.gname, get_cached_groupname(statbuf->st_gid), sizeof(header.gname));
 346
 347         if (tbInfo->hlInfo) {
 348                 /* This is a hard link */
 349                 header.typeflag = LNKTYPE;
 350                 strncpy(header.linkname, tbInfo->hlInfo->name,
 351                                 sizeof(header.linkname));
 352 # if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 353                 /* Write out long linkname if needed */
 354                 if (header.linkname[sizeof(header.linkname)-1])
 355                         writeLongname(tbInfo->tarFd, GNULONGLINK,
 356                                         tbInfo->hlInfo->name, 0);
 357 # endif
 358         } else if (S_ISLNK(statbuf->st_mode)) {
 359                 char *lpath = xmalloc_readlink_or_warn(fileName);
 360                 if (!lpath)
 361                         return FALSE;
 362                 header.typeflag = SYMTYPE;
 363                 strncpy(header.linkname, lpath, sizeof(header.linkname));
 364 # if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 365                 /* Write out long linkname if needed */
 366                 if (header.linkname[sizeof(header.linkname)-1])
 367                         writeLongname(tbInfo->tarFd, GNULONGLINK, lpath, 0);
 368 # else
 369                 /* If it is larger than 100 bytes, bail out */
 370                 if (header.linkname[sizeof(header.linkname)-1]) {
 371                         free(lpath);
 372                         bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
 373                         return FALSE;
 374                 }
 375 # endif
 376                 free(lpath);
 377         } else if (S_ISDIR(statbuf->st_mode)) {
 378                 header.typeflag = DIRTYPE;
 379                 /* Append '/' only if there is a space for it */
 380                 if (!header.name[sizeof(header.name)-1])
 381                         header.name[strlen(header.name)] = '/';
 382         } else if (S_ISCHR(statbuf->st_mode)) {
 383                 header.typeflag = CHRTYPE;
 384                 PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
 385                 PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
 386         } else if (S_ISBLK(statbuf->st_mode)) {
 387                 header.typeflag = BLKTYPE;
 388                 PUT_OCTAL(header.devmajor, major(statbuf->st_rdev));
 389                 PUT_OCTAL(header.devminor, minor(statbuf->st_rdev));
 390         } else if (S_ISFIFO(statbuf->st_mode)) {
 391                 header.typeflag = FIFOTYPE;
 392         } else if (S_ISREG(statbuf->st_mode)) {
 393                 /* header.size field is 12 bytes long */
 394                 /* Does octal-encoded size fit? */
 395                 uoff_t filesize = statbuf->st_size;
 396                 if (sizeof(filesize) <= 4
 397                  || filesize <= (uoff_t)0777777777777LL
 398                 ) {
 399                         PUT_OCTAL(header.size, filesize);
 400                 }
 401                 /* Does base256-encoded size fit?
 402                  * It always does unless off_t is wider than 64 bits.
 403                  */
 404                 else if (ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 405 # if ULLONG_MAX > 0xffffffffffffffffLL /* 2^64-1 */
 406                  && (filesize <= 0x3fffffffffffffffffffffffLL)
 407 # endif
 408                 ) {
 409                         /* GNU tar uses "base-256 encoding" for very large numbers.
 410                          * Encoding is binary, with highest bit always set as a marker
 411                          * and sign in next-highest bit:
 412                          * 80 00 .. 00 - zero
 413                          * bf ff .. ff - largest positive number
 414                          * ff ff .. ff - minus 1
 415                          * c0 00 .. 00 - smallest negative number
 416                          */
 417                         char *p8 = header.size + sizeof(header.size);
 418                         do {
 419                                 *--p8 = (uint8_t)filesize;
 420                                 filesize >>= 8;
 421                         } while (p8 != header.size);
 422                         *p8 |= 0x80;
 423                 } else {
 424                         bb_error_msg_and_die("can't store file '%s' "
 425                                 "of size %"OFF_FMT"u, aborting",
 426                                 fileName, statbuf->st_size);
 427                 }
 428                 header.typeflag = REGTYPE;
 429         } else {
 430                 bb_error_msg("%s: unknown file type", fileName);
 431                 return FALSE;
 432         }
 433
 434 # if ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 435         /* Write out long name if needed */
 436         /* (we, like GNU tar, output long linkname *before* long name) */
 437         if (header.name[sizeof(header.name)-1])
 438                 writeLongname(tbInfo->tarFd, GNULONGNAME,
 439                                 header_name, S_ISDIR(statbuf->st_mode));
 440 # endif
 441
 442         /* Now write the header out to disk */
 443         chksum_and_xwrite(tbInfo->tarFd, &header);
 444
 445         /* Now do the verbose thing (or not) */
 446         if (tbInfo->verboseFlag) {
 447                 FILE *vbFd = stdout;
 448
 449                 /* If archive goes to stdout, verbose goes to stderr */
 450                 if (tbInfo->tarFd == STDOUT_FILENO)
 451                         vbFd = stderr;
 452                 /* GNU "tar cvvf" prints "extended" listing a-la "ls -l" */
 453                 /* We don't have such excesses here: for us "v" == "vv" */
 454                 /* '/' is probably a GNUism */
 455                 fprintf(vbFd, "%s%s\n", header_name,
 456                                 S_ISDIR(statbuf->st_mode) ? "/" : "");
 457         }
 458
 459         return TRUE;
 460 }
 461
 462 # if ENABLE_FEATURE_TAR_FROM
 463 static int exclude_file(const llist_t *excluded_files, const char *file)
 464 {
 465         while (excluded_files) {
 466                 if (excluded_files->data[0] == '/') {
 467                         if (fnmatch(excluded_files->data, file,
 468                                         FNM_PATHNAME | FNM_LEADING_DIR) == 0)
 469                                 return 1;
 470                 } else {
 471                         const char *p;
 472
 473                         for (p = file; p[0] != '\0'; p++) {
 474                                 if ((p == file || p[-1] == '/')
 475                                  && p[0] != '/'
 476                                  && fnmatch(excluded_files->data, p,
 477                                                 FNM_PATHNAME | FNM_LEADING_DIR) == 0
 478                                 ) {
 479                                         return 1;
 480                                 }
 481                         }
 482                 }
 483                 excluded_files = excluded_files->link;
 484         }
 485
 486         return 0;
 487 }
 488 # else
 489 #  define exclude_file(excluded_files, file) 0
 490 # endif
 491
 492 static int FAST_FUNC writeFileToTarball(const char *fileName, struct stat *statbuf,
 493                         void *userData, int depth UNUSED_PARAM)
 494 {
 495         struct TarBallInfo *tbInfo = (struct TarBallInfo *) userData;
 496         const char *header_name;
 497         int inputFileFd = -1;
 498
 499         DBG("writeFileToTarball('%s')", fileName);
 500
 501         /* Strip leading '/' and such (must be before memorizing hardlink's name) */
 502         header_name = strip_unsafe_prefix(fileName);
 503
 504         if (header_name[0] == '\0')
 505                 return TRUE;
 506
 507         /* It is against the rules to archive a socket */
 508         if (S_ISSOCK(statbuf->st_mode)) {
 509                 bb_error_msg("%s: socket ignored", fileName);
 510                 return TRUE;
 511         }
 512
 513         /*
 514          * Check to see if we are dealing with a hard link.
 515          * If so -
 516          * Treat the first occurrence of a given dev/inode as a file while
 517          * treating any additional occurrences as hard links.  This is done
 518          * by adding the file information to the HardLinkInfo linked list.
 519          */
 520         tbInfo->hlInfo = NULL;
 521         if (!S_ISDIR(statbuf->st_mode) && statbuf->st_nlink > 1) {
 522                 DBG("'%s': st_nlink > 1", header_name);
 523                 tbInfo->hlInfo = findHardLinkInfo(tbInfo->hlInfoHead, statbuf);
 524                 if (tbInfo->hlInfo == NULL) {
 525                         DBG("'%s': addHardLinkInfo", header_name);
 526                         addHardLinkInfo(&tbInfo->hlInfoHead, statbuf, header_name);
 527                 }
 528         }
 529
 530         /* It is a bad idea to store the archive we are in the process of creating,
 531          * so check the device and inode to be sure that this particular file isn't
 532          * the new tarball */
 533         if (tbInfo->tarFileStatBuf.st_dev == statbuf->st_dev
 534          && tbInfo->tarFileStatBuf.st_ino == statbuf->st_ino
 535         ) {
 536                 bb_error_msg("%s: file is the archive; skipping", fileName);
 537                 return TRUE;
 538         }
 539
 540         if (exclude_file(tbInfo->excludeList, header_name))
 541                 return SKIP;
 542
 543 # if !ENABLE_FEATURE_TAR_GNU_EXTENSIONS
 544         if (strlen(header_name) >= NAME_SIZE) {
 545                 bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
 546                 return TRUE;
 547         }
 548 # endif
 549
 550         /* Is this a regular file? */
 551         if (tbInfo->hlInfo == NULL && S_ISREG(statbuf->st_mode)) {
 552                 /* open the file we want to archive, and make sure all is well */
 553                 inputFileFd = open_or_warn(fileName, O_RDONLY);
 554                 if (inputFileFd < 0) {
 555                         return FALSE;
 556                 }
 557         }
 558
 559         /* Add an entry to the tarball */
 560         if (writeTarHeader(tbInfo, header_name, fileName, statbuf) == FALSE) {
 561                 return FALSE;
 562         }
 563
 564         /* If it was a regular file, write out the body */
 565         if (inputFileFd >= 0) {
 566                 size_t readSize;
 567                 /* Write the file to the archive. */
 568                 /* We record size into header first, */
 569                 /* and then write out file. If file shrinks in between, */
 570                 /* tar will be corrupted. So we don't allow for that. */
 571                 /* NB: GNU tar 1.16 warns and pads with zeroes */
 572                 /* or even seeks back and updates header */
 573                 bb_copyfd_exact_size(inputFileFd, tbInfo->tarFd, statbuf->st_size);
 574                 ////off_t readSize;
 575                 ////readSize = bb_copyfd_size(inputFileFd, tbInfo->tarFd, statbuf->st_size);
 576                 ////if (readSize != statbuf->st_size && readSize >= 0) {
 577                 ////    bb_error_msg_and_die("short read from %s, aborting", fileName);
 578                 ////}
 579
 580                 /* Check that file did not grow in between? */
 581                 /* if (safe_read(inputFileFd, 1) == 1) warn but continue? */
 582
 583                 close(inputFileFd);
 584
 585                 /* Pad the file up to the tar block size */
 586                 /* (a few tricks here in the name of code size) */
 587                 readSize = (-(int)statbuf->st_size) & (TAR_BLOCK_SIZE-1);
 588                 memset(block_buf, 0, readSize);
 589                 xwrite(tbInfo->tarFd, block_buf, readSize);
 590         }
 591
 592         return TRUE;
 593 }
 594
 595 # if SEAMLESS_COMPRESSION
 596 /* Don't inline: vfork scares gcc and pessimizes code */
 597 static void NOINLINE vfork_compressor(int tar_fd, const char *gzip)
 598 {
 599         pid_t gzipPid;
 600
 601         // On Linux, vfork never unpauses parent early, although standard
 602         // allows for that. Do we want to waste bytes checking for it?
 603 #  define WAIT_FOR_CHILD 0
 604         volatile int vfork_exec_errno = 0;
 605         struct fd_pair gzipDataPipe;
 606 #  if WAIT_FOR_CHILD
 607         struct fd_pair gzipStatusPipe;
 608         xpiped_pair(gzipStatusPipe);
 609 #  endif
 610         xpiped_pair(gzipDataPipe);
 611
 612         signal(SIGPIPE, SIG_IGN); /* we only want EPIPE on errors */
 613
 614         gzipPid = xvfork();
 615
 616         if (gzipPid == 0) {
 617                 /* child */
 618                 /* NB: close _first_, then move fds! */
 619                 close(gzipDataPipe.wr);
 620 #  if WAIT_FOR_CHILD
 621                 close(gzipStatusPipe.rd);
 622                 /* gzipStatusPipe.wr will close only on exec -
 623                  * parent waits for this close to happen */
 624                 fcntl(gzipStatusPipe.wr, F_SETFD, FD_CLOEXEC);
 625 #  endif
 626                 xmove_fd(gzipDataPipe.rd, 0);
 627                 xmove_fd(tar_fd, 1);
 628                 /* exec gzip/bzip2 program/applet */
 629                 BB_EXECLP(gzip, gzip, "-f", (char *)0);
 630                 vfork_exec_errno = errno;
 631                 _exit(EXIT_FAILURE);
 632         }
 633
 634         /* parent */
 635         xmove_fd(gzipDataPipe.wr, tar_fd);
 636         close(gzipDataPipe.rd);
 637 #  if WAIT_FOR_CHILD
 638         close(gzipStatusPipe.wr);
 639         while (1) {
 640                 char buf;
 641                 int n;
 642
 643                 /* Wait until child execs (or fails to) */
 644                 n = full_read(gzipStatusPipe.rd, &buf, 1);
 645                 if (n < 0 /* && errno == EAGAIN */)
 646                         continue;       /* try it again */
 647         }
 648         close(gzipStatusPipe.rd);
 649 #  endif
 650         if (vfork_exec_errno) {
 651                 errno = vfork_exec_errno;
 652                 bb_perror_msg_and_die("can't execute '%s'", gzip);
 653         }
 654 }
 655 # endif /* SEAMLESS_COMPRESSION */
 656
 657
 658 # if !SEAMLESS_COMPRESSION
 659 /* Do not pass gzip flag to writeTarFile() */
 660 #define writeTarFile(tbInfo, recurseFlags, filelist, gzip) \
 661         writeTarFile(tbInfo, recurseFlags, filelist)
 662 # endif
 663 /* gcc 4.2.1 inlines it, making code bigger */
 664 static NOINLINE int writeTarFile(
 665         struct TarBallInfo *tbInfo,
 666         int recurseFlags,
 667         const llist_t *filelist,
 668         const char *gzip)
 669 {
 670         int errorFlag = FALSE;
 671
 672         /*tbInfo->hlInfoHead = NULL; - already is */
 673
 674         /* Store the stat info for the tarball's file, so
 675          * can avoid including the tarball into itself....  */
 676         xfstat(tbInfo->tarFd, &tbInfo->tarFileStatBuf, "can't stat tar file");
 677
 678 # if SEAMLESS_COMPRESSION
 679         if (gzip)
 680                 vfork_compressor(tbInfo->tarFd, gzip);
 681 # endif
 682
 683         /* Read the directory/files and iterate over them one at a time */
 684         while (filelist) {
 685                 if (!recursive_action(filelist->data, recurseFlags,
 686                                 writeFileToTarball, writeFileToTarball, tbInfo, 0)
 687                 ) {
 688                         errorFlag = TRUE;
 689                 }
 690                 filelist = filelist->link;
 691         }
 692         /* Write two empty blocks to the end of the archive */
 693         memset(block_buf, 0, 2*TAR_BLOCK_SIZE);
 694         xwrite(tbInfo->tarFd, block_buf, 2*TAR_BLOCK_SIZE);
 695
 696         /* To be pedantically correct, we would check if the tarball
 697          * is smaller than 20 tar blocks, and pad it if it was smaller,
 698          * but that isn't necessary for GNU tar interoperability, and
 699          * so is considered a waste of space */
 700
 701         /* Close so the child process (if any) will exit */
 702         close(tbInfo->tarFd);
 703
 704         /* Hang up the tools, close up shop, head home */
 705         if (ENABLE_FEATURE_CLEAN_UP)
 706                 freeHardLinkInfo(&tbInfo->hlInfoHead);
 707
 708         if (errorFlag)
 709                 bb_error_msg("error exit delayed from previous errors");
 710
 711 # if SEAMLESS_COMPRESSION
 712         if (gzip) {
 713                 int status;
 714                 if (safe_waitpid(-1, &status, 0) == -1)
 715                         bb_perror_msg("waitpid");
 716                 else if (!WIFEXITED(status) || WEXITSTATUS(status))
 717                         /* gzip was killed or has exited with nonzero! */
 718                         errorFlag = TRUE;
 719         }
 720 # endif
 721         return errorFlag;
 722 }
 723
 724 #else /* !FEATURE_TAR_CREATE */
 725
 726 # define writeTarFile(...) 0
 727
 728 #endif
 729
 730 #if ENABLE_FEATURE_TAR_FROM
 731 static llist_t *append_file_list_to_list(llist_t *list)
 732 {
 733         llist_t *newlist = NULL;
 734
 735         while (list) {
 736                 FILE *src_stream;
 737                 char *line;
 738
 739                 src_stream = xfopen_stdin(llist_pop(&list));
 740                 while ((line = xmalloc_fgetline(src_stream)) != NULL) {
 741                         /* kill trailing '/' unless the string is just "/" */
 742                         char *cp = last_char_is(line, '/');
 743                         if (cp > line)
 744                                 *cp = '\0';
 745                         llist_add_to_end(&newlist, line);
 746                 }
 747                 fclose(src_stream);
 748         }
 749         return newlist;
 750 }
 751 #endif
 752
 753 //usage:#define tar_trivial_usage
 754 //usage:        IF_FEATURE_TAR_CREATE("c|") "x|t [-"
 755 //usage:        IF_FEATURE_SEAMLESS_Z("Z")
 756 //usage:        IF_FEATURE_SEAMLESS_GZ("z")
 757 //usage:        IF_FEATURE_SEAMLESS_XZ("J")
 758 //usage:        IF_FEATURE_SEAMLESS_BZ2("j")
 759 //usage:        IF_FEATURE_SEAMLESS_LZMA("a")
 760 //usage:        IF_FEATURE_TAR_CREATE("h")
 761 //usage:        IF_FEATURE_TAR_NOPRESERVE_TIME("m")
 762 //usage:        "vokO] "
 763 //usage:        "[-f TARFILE] [-C DIR] "
 764 //usage:        IF_FEATURE_TAR_FROM("[-T FILE] [-X FILE] "IF_FEATURE_TAR_LONG_OPTIONS("[--exclude PATTERN]... "))
 765 //usage:        "[FILE]..."
 766 //usage:#define tar_full_usage "\n\n"
 767 //usage:        IF_FEATURE_TAR_CREATE("Create, extract, ")
 768 //usage:        IF_NOT_FEATURE_TAR_CREATE("Extract ")
 769 //usage:        "or list files from a tar file"
 770 //usage:     "\n"
 771 //usage:        IF_FEATURE_TAR_CREATE(
 772 //usage:     "\n        c       Create"
 773 //usage:        )
 774 //usage:     "\n        x       Extract"
 775 //usage:     "\n        t       List"
 776 //usage:     "\n        -f FILE Name of TARFILE ('-' for stdin/out)"
 777 //usage:     "\n        -C DIR  Change to DIR before operation"
 778 //usage:     "\n        -v      Verbose"
 779 //usage:     "\n        -O      Extract to stdout"
 780 //usage:        IF_FEATURE_TAR_NOPRESERVE_TIME(
 781 //usage:     "\n        -m      Don't restore mtime"
 782 //usage:        )
 783 //usage:     "\n        -o      Don't restore user:group"
 784 ///////:-p - accepted but ignored, restores mode (aliases in GNU tar: --preserve-permissions, --same-permissions)
 785 //usage:     "\n        -k      Don't replace existing files"
 786 //usage:        IF_FEATURE_SEAMLESS_Z(
 787 //usage:     "\n        -Z      (De)compress using compress"
 788 //usage:        )
 789 //usage:        IF_FEATURE_SEAMLESS_GZ(
 790 //usage:     "\n        -z      (De)compress using gzip"
 791 //usage:        )
 792 //usage:        IF_FEATURE_SEAMLESS_XZ(
 793 //usage:     "\n        -J      (De)compress using xz"
 794 //usage:        )
 795 //usage:        IF_FEATURE_SEAMLESS_BZ2(
 796 //usage:     "\n        -j      (De)compress using bzip2"
 797 //usage:        )
 798 //usage:        IF_FEATURE_SEAMLESS_LZMA(
 799 //usage:     "\n        -a      (De)compress using lzma"
 800 //usage:        )
 801 //usage:        IF_FEATURE_TAR_CREATE(
 802 //usage:     "\n        -h      Follow symlinks"
 803 //usage:        )
 804 //usage:        IF_FEATURE_TAR_FROM(
 805 //usage:     "\n        -T FILE File with names to include"
 806 //usage:     "\n        -X FILE File with glob patterns to exclude"
 807 //usage:        IF_FEATURE_TAR_LONG_OPTIONS(
 808 //usage:     "\n        --exclude PATTERN       Glob pattern to exclude"
 809 //usage:        )
 810 //usage:        )
 811 //usage:
 812 //usage:#define tar_example_usage
 813 //usage:       "$ zcat /tmp/tarball.tar.gz | tar -xf -\n"
 814 //usage:       "$ tar -cf /tmp/tarball.tar /usr/local\n"
 815
 816 // Supported but aren't in --help:
 817 //      no-recursion
 818 //      numeric-owner
 819 //      no-same-permissions
 820 //      overwrite
 821 //IF_FEATURE_TAR_TO_COMMAND(
 822 //      to-command
 823 //)
 824
 825 enum {
 826         OPTBIT_KEEP_OLD = 8,
 827         IF_FEATURE_TAR_CREATE(   OPTBIT_CREATE      ,)
 828         IF_FEATURE_TAR_CREATE(   OPTBIT_DEREFERENCE ,)
 829         IF_FEATURE_SEAMLESS_BZ2( OPTBIT_BZIP2       ,)
 830         IF_FEATURE_SEAMLESS_LZMA(OPTBIT_LZMA        ,)
 831         IF_FEATURE_TAR_FROM(     OPTBIT_INCLUDE_FROM,)
 832         IF_FEATURE_TAR_FROM(     OPTBIT_EXCLUDE_FROM,)
 833         IF_FEATURE_SEAMLESS_GZ(  OPTBIT_GZIP        ,)
 834         IF_FEATURE_SEAMLESS_XZ(  OPTBIT_XZ          ,) // 16th bit
 835         IF_FEATURE_SEAMLESS_Z(   OPTBIT_COMPRESS    ,)
 836         IF_FEATURE_TAR_NOPRESERVE_TIME(OPTBIT_NOPRESERVE_TIME,)
 837 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
 838         OPTBIT_STRIP_COMPONENTS,
 839         OPTBIT_NORECURSION,
 840         IF_FEATURE_TAR_TO_COMMAND(OPTBIT_2COMMAND   ,)
 841         OPTBIT_NUMERIC_OWNER,
 842         OPTBIT_NOPRESERVE_PERM,
 843         OPTBIT_OVERWRITE,
 844 #endif
 845         OPT_TEST         = 1 << 0, // t
 846         OPT_EXTRACT      = 1 << 1, // x
 847         OPT_BASEDIR      = 1 << 2, // C
 848         OPT_TARNAME      = 1 << 3, // f
 849         OPT_2STDOUT      = 1 << 4, // O
 850         OPT_NOPRESERVE_OWNER = 1 << 5, // o == no-same-owner
 851         OPT_P            = 1 << 6, // p
 852         OPT_VERBOSE      = 1 << 7, // v
 853         OPT_KEEP_OLD     = 1 << 8, // k
 854         OPT_CREATE       = IF_FEATURE_TAR_CREATE(   (1 << OPTBIT_CREATE      )) + 0, // c
 855         OPT_DEREFERENCE  = IF_FEATURE_TAR_CREATE(   (1 << OPTBIT_DEREFERENCE )) + 0, // h
 856         OPT_BZIP2        = IF_FEATURE_SEAMLESS_BZ2( (1 << OPTBIT_BZIP2       )) + 0, // j
 857         OPT_LZMA         = IF_FEATURE_SEAMLESS_LZMA((1 << OPTBIT_LZMA        )) + 0, // a
 858         OPT_INCLUDE_FROM = IF_FEATURE_TAR_FROM(     (1 << OPTBIT_INCLUDE_FROM)) + 0, // T
 859         OPT_EXCLUDE_FROM = IF_FEATURE_TAR_FROM(     (1 << OPTBIT_EXCLUDE_FROM)) + 0, // X
 860         OPT_GZIP         = IF_FEATURE_SEAMLESS_GZ(  (1 << OPTBIT_GZIP        )) + 0, // z
 861         OPT_XZ           = IF_FEATURE_SEAMLESS_XZ(  (1 << OPTBIT_XZ          )) + 0, // J
 862         OPT_COMPRESS     = IF_FEATURE_SEAMLESS_Z(   (1 << OPTBIT_COMPRESS    )) + 0, // Z
 863         OPT_NOPRESERVE_TIME  = IF_FEATURE_TAR_NOPRESERVE_TIME((1 << OPTBIT_NOPRESERVE_TIME)) + 0, // m
 864         OPT_STRIP_COMPONENTS = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_STRIP_COMPONENTS)) + 0, // strip-components
 865         OPT_NORECURSION      = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NORECURSION    )) + 0, // no-recursion
 866         OPT_2COMMAND         = IF_FEATURE_TAR_TO_COMMAND(  (1 << OPTBIT_2COMMAND       )) + 0, // to-command
 867         OPT_NUMERIC_OWNER    = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NUMERIC_OWNER  )) + 0, // numeric-owner
 868         OPT_NOPRESERVE_PERM  = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_NOPRESERVE_PERM)) + 0, // no-same-permissions
 869         OPT_OVERWRITE        = IF_FEATURE_TAR_LONG_OPTIONS((1 << OPTBIT_OVERWRITE      )) + 0, // overwrite
 870
 871         OPT_ANY_COMPRESS = (OPT_BZIP2 | OPT_LZMA | OPT_GZIP | OPT_XZ | OPT_COMPRESS),
 872 };
 873 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
 874 static const char tar_longopts[] ALIGN1 =
 875         "list\0"                No_argument       "t"
 876         "extract\0"             No_argument       "x"
 877         "directory\0"           Required_argument "C"
 878         "file\0"                Required_argument "f"
 879         "to-stdout\0"           No_argument       "O"
 880         /* do not restore owner */
 881         /* Note: GNU tar handles 'o' as no-same-owner only on extract,
 882          * on create, 'o' is --old-archive. We do not support --old-archive. */
 883         "no-same-owner\0"       No_argument       "o"
 884         "same-permissions\0"    No_argument       "p"
 885         "verbose\0"             No_argument       "v"
 886         "keep-old\0"            No_argument       "k"
 887 # if ENABLE_FEATURE_TAR_CREATE
 888         "create\0"              No_argument       "c"
 889         "dereference\0"         No_argument       "h"
 890 # endif
 891 # if ENABLE_FEATURE_SEAMLESS_BZ2
 892         "bzip2\0"               No_argument       "j"
 893 # endif
 894 # if ENABLE_FEATURE_SEAMLESS_LZMA
 895         "lzma\0"                No_argument       "a"
 896 # endif
 897 # if ENABLE_FEATURE_TAR_FROM
 898         "files-from\0"          Required_argument "T"
 899         "exclude-from\0"        Required_argument "X"
 900 # endif
 901 # if ENABLE_FEATURE_SEAMLESS_GZ
 902         "gzip\0"                No_argument       "z"
 903 # endif
 904 # if ENABLE_FEATURE_SEAMLESS_XZ
 905         "xz\0"                  No_argument       "J"
 906 # endif
 907 # if ENABLE_FEATURE_SEAMLESS_Z
 908         "compress\0"            No_argument       "Z"
 909 # endif
 910 # if ENABLE_FEATURE_TAR_NOPRESERVE_TIME
 911         "touch\0"               No_argument       "m"
 912 # endif
 913         "strip-components\0"    Required_argument "\xf9"
 914         "no-recursion\0"        No_argument       "\xfa"
 915 # if ENABLE_FEATURE_TAR_TO_COMMAND
 916         "to-command\0"          Required_argument "\xfb"
 917 # endif
 918         /* use numeric uid/gid from tar header, not textual */
 919         "numeric-owner\0"       No_argument       "\xfc"
 920         /* do not restore mode */
 921         "no-same-permissions\0" No_argument       "\xfd"
 922         /* on unpack, open with O_TRUNC and !O_EXCL */
 923         "overwrite\0"           No_argument       "\xfe"
 924         /* --exclude takes next bit position in option mask, */
 925         /* therefore we have to put it _after_ --no-same-permissions */
 926 # if ENABLE_FEATURE_TAR_FROM
 927         "exclude\0"             Required_argument "\xff"
 928 # endif
 929         ;
 930 # define GETOPT32 getopt32long
 931 # define LONGOPTS ,tar_longopts
 932 #else
 933 # define GETOPT32 getopt32
 934 # define LONGOPTS
 935 #endif
 936
 937 int tar_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 938 int tar_main(int argc UNUSED_PARAM, char **argv)
 939 {
 940         archive_handle_t *tar_handle;
 941         char *base_dir = NULL;
 942         const char *tar_filename = "-";
 943         unsigned opt;
 944         int verboseFlag = 0;
 945 #if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
 946         llist_t *excludes = NULL;
 947 #endif
 948         INIT_G();
 949
 950         /* Initialise default values */
 951         tar_handle = init_handle();
 952         tar_handle->ah_flags = ARCHIVE_CREATE_LEADING_DIRS
 953                              | ARCHIVE_RESTORE_DATE
 954                              | ARCHIVE_UNLINK_OLD;
 955
 956         /* Apparently only root's tar preserves perms (see bug 3844) */
 957         if (getuid() != 0)
 958                 tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_PERM;
 959
 960 #if ENABLE_DESKTOP
 961         /* Lie to buildroot when it starts asking stupid questions. */
 962         if (argv[1] && strcmp(argv[1], "--version") == 0) {
 963                 // Output of 'tar --version' examples:
 964                 // tar (GNU tar) 1.15.1
 965                 // tar (GNU tar) 1.25
 966                 // bsdtar 2.8.3 - libarchive 2.8.3
 967                 puts("tar (busybox) " BB_VER);
 968                 return 0;
 969         }
 970 #endif
 971         if (argv[1] && argv[1][0] != '-' && argv[1][0] != '\0') {
 972                 /* Compat:
 973                  * 1st argument without dash handles options with parameters
 974                  * differently from dashed one: it takes *next argv[i]*
 975                  * as parameter even if there are more chars in 1st argument:
 976                  *  "tar fx TARFILE" - "x" is not taken as f's param
 977                  *  but is interpreted as -x option
 978                  *  "tar -xf TARFILE" - dashed equivalent of the above
 979                  *  "tar -fx ..." - "x" is taken as f's param
 980                  * getopt32 wouldn't handle 1st command correctly.
 981                  * Unfortunately, people do use such commands.
 982                  * We massage argv[1] to work around it by moving 'f'
 983                  * to the end of the string.
 984                  * More contrived "tar fCx TARFILE DIR" still fails,
 985                  * but such commands are much less likely to be used.
 986                  */
 987                 char *f = strchr(argv[1], 'f');
 988                 if (f) {
 989                         while (f[1] != '\0') {
 990                                 *f = f[1];
 991                                 f++;
 992                         }
 993                         *f = 'f';
 994                 }
 995                 /* Prepend '-' to the first argument  */
 996                 argv[1] = xasprintf("-%s", argv[1]);
 997         }
 998         opt = GETOPT32(argv, "^"
 999                 "txC:f:Oopvk"
1000                 IF_FEATURE_TAR_CREATE(   "ch"    )
1001                 IF_FEATURE_SEAMLESS_BZ2( "j"     )
1002                 IF_FEATURE_SEAMLESS_LZMA("a"     )
1003                 IF_FEATURE_TAR_FROM(     "T:*X:*")
1004                 IF_FEATURE_SEAMLESS_GZ(  "z"     )
1005                 IF_FEATURE_SEAMLESS_XZ(  "J"     )
1006                 IF_FEATURE_SEAMLESS_Z(   "Z"     )
1007                 IF_FEATURE_TAR_NOPRESERVE_TIME("m")
1008                 IF_FEATURE_TAR_LONG_OPTIONS("\xf9:") // --strip-components
1009                 "\0"
1010                 "tt:vv:" // count -t,-v
1011 #if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
1012                 "\xff::" // --exclude=PATTERN is a list
1013 #endif
1014                 IF_FEATURE_TAR_CREATE("c:") "t:x:" // at least one of these is reqd
1015                 IF_FEATURE_TAR_CREATE("c--tx:t--cx:x--ct") // mutually exclusive
1016                 IF_NOT_FEATURE_TAR_CREATE("t--x:x--t") // mutually exclusive
1017 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
1018                 ":\xf9+" // --strip-components=NUM
1019 #endif
1020                 LONGOPTS
1021                 , &base_dir // -C dir
1022                 , &tar_filename // -f filename
1023                 IF_FEATURE_TAR_FROM(, &(tar_handle->accept)) // T
1024                 IF_FEATURE_TAR_FROM(, &(tar_handle->reject)) // X
1025 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
1026                 , &tar_handle->tar__strip_components // --strip-components
1027 #endif
1028                 IF_FEATURE_TAR_TO_COMMAND(, &(tar_handle->tar__to_command)) // --to-command
1029 #if ENABLE_FEATURE_TAR_LONG_OPTIONS && ENABLE_FEATURE_TAR_FROM
1030                 , &excludes // --exclude
1031 #endif
1032                 , &verboseFlag // combined count for -t and -v
1033                 , &verboseFlag // combined count for -t and -v
1034                 );
1035 #if DBG_OPTION_PARSING
1036         bb_error_msg("opt: 0x%08x", opt);
1037 # define showopt(o) bb_error_msg("opt & %s(%x): %x", #o, o, opt & o);
1038         showopt(OPT_TEST            );
1039         showopt(OPT_EXTRACT         );
1040         showopt(OPT_BASEDIR         );
1041         showopt(OPT_TARNAME         );
1042         showopt(OPT_2STDOUT         );
1043         showopt(OPT_NOPRESERVE_OWNER);
1044         showopt(OPT_P               );
1045         showopt(OPT_VERBOSE         );
1046         showopt(OPT_KEEP_OLD        );
1047         showopt(OPT_CREATE          );
1048         showopt(OPT_DEREFERENCE     );
1049         showopt(OPT_BZIP2           );
1050         showopt(OPT_LZMA            );
1051         showopt(OPT_INCLUDE_FROM    );
1052         showopt(OPT_EXCLUDE_FROM    );
1053         showopt(OPT_GZIP            );
1054         showopt(OPT_XZ              );
1055         showopt(OPT_COMPRESS        );
1056         showopt(OPT_NOPRESERVE_TIME );
1057         showopt(OPT_STRIP_COMPONENTS);
1058         showopt(OPT_NORECURSION     );
1059         showopt(OPT_2COMMAND        );
1060         showopt(OPT_NUMERIC_OWNER   );
1061         showopt(OPT_NOPRESERVE_PERM );
1062         showopt(OPT_OVERWRITE       );
1063         showopt(OPT_ANY_COMPRESS    );
1064         bb_error_msg("base_dir:'%s'", base_dir);
1065         bb_error_msg("tar_filename:'%s'", tar_filename);
1066         bb_error_msg("verboseFlag:%d", verboseFlag);
1067         bb_error_msg("tar_handle->tar__to_command:'%s'", tar_handle->tar__to_command);
1068         bb_error_msg("tar_handle->tar__strip_components:%u", tar_handle->tar__strip_components);
1069         return 0;
1070 # undef showopt
1071 #endif
1072         argv += optind;
1073
1074         if (verboseFlag)
1075                 tar_handle->action_header = header_verbose_list;
1076         if (verboseFlag == 1)
1077                 tar_handle->action_header = header_list;
1078
1079         if (opt & OPT_EXTRACT)
1080                 tar_handle->action_data = data_extract_all;
1081
1082         if (opt & OPT_2STDOUT)
1083                 tar_handle->action_data = data_extract_to_stdout;
1084
1085         if (opt & OPT_2COMMAND) {
1086                 putenv((char*)"TAR_FILETYPE=f");
1087                 signal(SIGPIPE, SIG_IGN);
1088                 tar_handle->action_data = data_extract_to_command;
1089                 IF_FEATURE_TAR_TO_COMMAND(tar_handle->tar__to_command_shell = xstrdup(get_shell_name());)
1090         }
1091
1092         if (opt & OPT_KEEP_OLD)
1093                 tar_handle->ah_flags &= ~ARCHIVE_UNLINK_OLD;
1094
1095         if (opt & OPT_NUMERIC_OWNER)
1096                 tar_handle->ah_flags |= ARCHIVE_NUMERIC_OWNER;
1097
1098         if (opt & OPT_NOPRESERVE_OWNER)
1099                 tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_OWNER;
1100
1101         if (opt & OPT_NOPRESERVE_PERM)
1102                 tar_handle->ah_flags |= ARCHIVE_DONT_RESTORE_PERM;
1103
1104         if (opt & OPT_OVERWRITE) {
1105                 tar_handle->ah_flags &= ~ARCHIVE_UNLINK_OLD;
1106                 tar_handle->ah_flags |= ARCHIVE_O_TRUNC;
1107         }
1108
1109         if (opt & OPT_NOPRESERVE_TIME)
1110                 tar_handle->ah_flags &= ~ARCHIVE_RESTORE_DATE;
1111
1112 #if ENABLE_FEATURE_TAR_FROM
1113         tar_handle->reject = append_file_list_to_list(tar_handle->reject);
1114 # if ENABLE_FEATURE_TAR_LONG_OPTIONS
1115         /* Append excludes to reject */
1116         while (excludes) {
1117                 llist_t *next = excludes->link;
1118                 excludes->link = tar_handle->reject;
1119                 tar_handle->reject = excludes;
1120                 excludes = next;
1121         }
1122 # endif
1123         tar_handle->accept = append_file_list_to_list(tar_handle->accept);
1124 #endif
1125
1126         /* Setup an array of filenames to work with */
1127         /* TODO: This is the same as in ar, make a separate function? */
1128         while (*argv) {
1129                 /* kill trailing '/' unless the string is just "/" */
1130                 char *cp = last_char_is(*argv, '/');
1131                 if (cp > *argv)
1132                         *cp = '\0';
1133                 llist_add_to_end(&tar_handle->accept, *argv);
1134                 argv++;
1135         }
1136
1137         if (tar_handle->accept || tar_handle->reject)
1138                 tar_handle->filter = filter_accept_reject_list;
1139
1140         /* Open the tar file */
1141         {
1142                 int tar_fd = STDIN_FILENO;
1143                 int flags = O_RDONLY;
1144
1145                 if (opt & OPT_CREATE) {
1146                         /* Make sure there is at least one file to tar up */
1147                         if (tar_handle->accept == NULL)
1148                                 bb_error_msg_and_die("empty archive");
1149
1150                         tar_fd = STDOUT_FILENO;
1151                         /* Mimicking GNU tar 1.15.1: */
1152                         flags = O_WRONLY | O_CREAT | O_TRUNC;
1153                 }
1154
1155                 if (LONE_DASH(tar_filename)) {
1156                         tar_handle->src_fd = tar_fd;
1157                         tar_handle->seek = seek_by_read;
1158                 } else {
1159                         if (ENABLE_FEATURE_TAR_AUTODETECT
1160                          && flags == O_RDONLY
1161                          && !(opt & OPT_ANY_COMPRESS)
1162                         ) {
1163                                 tar_handle->src_fd = open_zipped(tar_filename, /*fail_if_not_compressed:*/ 0);
1164                                 if (tar_handle->src_fd < 0)
1165                                         bb_perror_msg_and_die("can't open '%s'", tar_filename);
1166                         } else {
1167                                 tar_handle->src_fd = xopen(tar_filename, flags);
1168                         }
1169                 }
1170         }
1171
1172         if (base_dir)
1173                 xchdir(base_dir);
1174
1175 #if ENABLE_FEATURE_TAR_CREATE
1176         /* Create an archive */
1177         if (opt & OPT_CREATE) {
1178                 struct TarBallInfo *tbInfo;
1179 # if SEAMLESS_COMPRESSION
1180                 const char *zipMode = NULL;
1181                 if (opt & OPT_COMPRESS)
1182                         zipMode = "compress";
1183                 if (opt & OPT_GZIP)
1184                         zipMode = "gzip";
1185                 if (opt & OPT_BZIP2)
1186                         zipMode = "bzip2";
1187                 if (opt & OPT_LZMA)
1188                         zipMode = "lzma";
1189                 if (opt & OPT_XZ)
1190                         zipMode = "xz";
1191 # endif
1192                 tbInfo = xzalloc(sizeof(*tbInfo));
1193                 tbInfo->tarFd = tar_handle->src_fd;
1194                 tbInfo->verboseFlag = verboseFlag;
1195 # if ENABLE_FEATURE_TAR_FROM
1196                 tbInfo->excludeList = tar_handle->reject;
1197 # endif
1198                 /* NB: writeTarFile() closes tar_handle->src_fd */
1199                 return writeTarFile(tbInfo,
1200                                 (opt & OPT_DEREFERENCE ? ACTION_FOLLOWLINKS : 0)
1201                                 | (opt & OPT_NORECURSION ? 0 : ACTION_RECURSE),
1202                                 tar_handle->accept,
1203                                 zipMode);
1204         }
1205 #endif
1206
1207         if (opt & OPT_ANY_COMPRESS) {
1208                 USE_FOR_MMU(IF_DESKTOP(long long) int FAST_FUNC (*xformer)(transformer_state_t *xstate);)
1209                 USE_FOR_NOMMU(const char *xformer_prog;)
1210
1211                 if (opt & OPT_COMPRESS) {
1212                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_Z(xformer = unpack_Z_stream;))
1213                         USE_FOR_NOMMU(xformer_prog = "uncompress";)
1214                 }
1215                 if (opt & OPT_GZIP) {
1216                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_GZ(xformer = unpack_gz_stream;))
1217                         USE_FOR_NOMMU(xformer_prog = "gunzip";)
1218                 }
1219                 if (opt & OPT_BZIP2) {
1220                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_BZ2(xformer = unpack_bz2_stream;))
1221                         USE_FOR_NOMMU(xformer_prog = "bunzip2";)
1222                 }
1223                 if (opt & OPT_LZMA) {
1224                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_LZMA(xformer = unpack_lzma_stream;))
1225                         USE_FOR_NOMMU(xformer_prog = "unlzma";)
1226                 }
1227                 if (opt & OPT_XZ) {
1228                         USE_FOR_MMU(IF_FEATURE_SEAMLESS_XZ(xformer = unpack_xz_stream;))
1229                         USE_FOR_NOMMU(xformer_prog = "unxz";)
1230                 }
1231
1232                 fork_transformer_with_sig(tar_handle->src_fd, xformer, xformer_prog);
1233                 /* Can't lseek over pipes */
1234                 tar_handle->seek = seek_by_read;
1235                 /*tar_handle->offset = 0; - already is */
1236         }
1237
1238         /* Zero processed headers (== empty file) is not a valid tarball.
1239          * We (ab)use bb_got_signal as exitcode here,
1240          * because check_errors_in_children() uses _it_ as error indicator.
1241          */
1242         bb_got_signal = EXIT_FAILURE;
1243
1244         while (get_header_tar(tar_handle) == EXIT_SUCCESS)
1245                 bb_got_signal = EXIT_SUCCESS; /* saw at least one header, good */
1246
1247         create_symlinks_from_list(tar_handle->symlink_placeholders);
1248
1249         /* Check that every file that should have been extracted was */
1250         while (tar_handle->accept) {
1251                 if (!find_list_entry(tar_handle->reject, tar_handle->accept->data)
1252                  && !find_list_entry(tar_handle->passed, tar_handle->accept->data)
1253                 ) {
1254                         bb_error_msg_and_die("%s: not found in archive",
1255                                 tar_handle->accept->data);
1256                 }
1257                 tar_handle->accept = tar_handle->accept->link;
1258         }
1259         if (ENABLE_FEATURE_CLEAN_UP /* && tar_handle->src_fd != STDIN_FILENO */)
1260                 close(tar_handle->src_fd);
1261
1262         if (SEAMLESS_COMPRESSION || OPT_COMPRESS) {
1263                 /* Set bb_got_signal to 1 if a child died with !0 exitcode */
1264                 check_errors_in_children(0);
1265         }
1266
1267         return bb_got_signal;
1268 }