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