busybox/archival/tar.c
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   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*/
 146typedef 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 */
 155typedef 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 */
 172enum {
 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;) */
 187static 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
 203static 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 ;) */
 220static 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. */
 237static 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
 257static 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
 284static 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 */
 326static 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
 463static 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
 492static 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 */
 597static 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 */
 664static 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
 731static 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
 825enum {
 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
 874static 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
 937int tar_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 938int 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_links_from_list(tar_handle->link_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}
1269