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  *  Glenn McGrath <bug1@iinet.net.au>
   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 the 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 tarball for details.
  24  */
  25
  26 #include "busybox.h"
  27 #include "unarchive.h"
  28 #include <fnmatch.h>
  29 #include <getopt.h>
  30
  31 #if ENABLE_FEATURE_TAR_CREATE
  32
  33 /* Tar file constants  */
  34
  35 #define TAR_BLOCK_SIZE          512
  36
  37 /* POSIX tar Header Block, from POSIX 1003.1-1990  */
  38 #define NAME_SIZE      100
  39 #define NAME_SIZE_STR "100"
  40 struct TarHeader {                /* byte offset */
  41         char name[NAME_SIZE];     /*   0-99 */
  42         char mode[8];             /* 100-107 */
  43         char uid[8];              /* 108-115 */
  44         char gid[8];              /* 116-123 */
  45         char size[12];            /* 124-135 */
  46         char mtime[12];           /* 136-147 */
  47         char chksum[8];           /* 148-155 */
  48         char typeflag;            /* 156-156 */
  49         char linkname[NAME_SIZE]; /* 157-256 */
  50         char magic[6];            /* 257-262 */
  51         char version[2];          /* 263-264 */
  52         char uname[32];           /* 265-296 */
  53         char gname[32];           /* 297-328 */
  54         char devmajor[8];         /* 329-336 */
  55         char devminor[8];         /* 337-344 */
  56         char prefix[155];         /* 345-499 */
  57         char padding[12];         /* 500-512 (pad to exactly the TAR_BLOCK_SIZE) */
  58 };
  59 typedef struct TarHeader TarHeader;
  60
  61 /*
  62 ** writeTarFile(), writeFileToTarball(), and writeTarHeader() are
  63 ** the only functions that deal with the HardLinkInfo structure.
  64 ** Even these functions use the xxxHardLinkInfo() functions.
  65 */
  66 typedef struct HardLinkInfo HardLinkInfo;
  67 struct HardLinkInfo {
  68         HardLinkInfo *next;     /* Next entry in list */
  69         dev_t dev;                      /* Device number */
  70         ino_t ino;                      /* Inode number */
  71         short linkCount;        /* (Hard) Link Count */
  72         char name[1];           /* Start of filename (must be last) */
  73 };
  74
  75 /* Some info to be carried along when creating a new tarball */
  76 struct TarBallInfo {
  77         int tarFd;                              /* Open-for-write file descriptor
  78                                                            for the tarball */
  79         struct stat statBuf;    /* Stat info for the tarball, letting
  80                                                            us know the inode and device that the
  81                                                            tarball lives, so we can avoid trying
  82                                                            to include the tarball into itself */
  83         int verboseFlag;                /* Whether to print extra stuff or not */
  84         const llist_t *excludeList;     /* List of files to not include */
  85         HardLinkInfo *hlInfoHead;       /* Hard Link Tracking Information */
  86         HardLinkInfo *hlInfo;   /* Hard Link Info for the current file */
  87 };
  88 typedef struct TarBallInfo TarBallInfo;
  89
  90 /* A nice enum with all the possible tar file content types */
  91 enum TarFileType {
  92         REGTYPE = '0',          /* regular file */
  93         REGTYPE0 = '\0',        /* regular file (ancient bug compat) */
  94         LNKTYPE = '1',          /* hard link */
  95         SYMTYPE = '2',          /* symbolic link */
  96         CHRTYPE = '3',          /* character special */
  97         BLKTYPE = '4',          /* block special */
  98         DIRTYPE = '5',          /* directory */
  99         FIFOTYPE = '6',         /* FIFO special */
 100         CONTTYPE = '7',         /* reserved */
 101         GNULONGLINK = 'K',      /* GNU long (>100 chars) link name */
 102         GNULONGNAME = 'L',      /* GNU long (>100 chars) file name */
 103 };
 104 typedef enum TarFileType TarFileType;
 105
 106 /* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */
 107 static void addHardLinkInfo(HardLinkInfo ** hlInfoHeadPtr,
 108                                         struct stat *statbuf,
 109                                         const char *fileName)
 110 {
 111         /* Note: hlInfoHeadPtr can never be NULL! */
 112         HardLinkInfo *hlInfo;
 113
 114         hlInfo = xmalloc(sizeof(HardLinkInfo) + strlen(fileName));
 115         hlInfo->next = *hlInfoHeadPtr;
 116         *hlInfoHeadPtr = hlInfo;
 117         hlInfo->dev = statbuf->st_dev;
 118         hlInfo->ino = statbuf->st_ino;
 119         hlInfo->linkCount = statbuf->st_nlink;
 120         strcpy(hlInfo->name, fileName);
 121 }
 122
 123 static void freeHardLinkInfo(HardLinkInfo ** hlInfoHeadPtr)
 124 {
 125         HardLinkInfo *hlInfo;
 126         HardLinkInfo *hlInfoNext;
 127
 128         if (hlInfoHeadPtr) {
 129                 hlInfo = *hlInfoHeadPtr;
 130                 while (hlInfo) {
 131                         hlInfoNext = hlInfo->next;
 132                         free(hlInfo);
 133                         hlInfo = hlInfoNext;
 134                 }
 135                 *hlInfoHeadPtr = NULL;
 136         }
 137         return;
 138 }
 139
 140 /* Might be faster (and bigger) if the dev/ino were stored in numeric order;) */
 141 static HardLinkInfo *findHardLinkInfo(HardLinkInfo * hlInfo, struct stat *statbuf)
 142 {
 143         while (hlInfo) {
 144                 if ((statbuf->st_ino == hlInfo->ino) && (statbuf->st_dev == hlInfo->dev))
 145                         break;
 146                 hlInfo = hlInfo->next;
 147         }
 148         return hlInfo;
 149 }
 150
 151 /* Put an octal string into the specified buffer.
 152  * The number is zero padded and possibly null terminated.
 153  * Returns TRUE if successful. - DISABLED (no caller ever checked) */
 154 /* FIXME: we leave field untouched if value doesn't fit. */
 155 /* This is not good - what will happen at untar time?? */
 156 static void putOctal(char *cp, int len, long long value)
 157 {
 158         int tempLength;
 159         /* long long for the sake of storing lengths of 4Gb+ files */
 160         /* (we are bust anyway after 64Gb: it doesn't fit into the field) */
 161         char tempBuffer[sizeof(long long)*3+1];
 162         char *tempString = tempBuffer;
 163
 164         /* Create a string of the specified length with
 165          * leading zeroes and the octal number, and a trailing null.  */
 166         tempLength = sprintf(tempBuffer, "%0*llo", len - 1, value);
 167
 168         /* If the string is too large, suppress leading 0's.  */
 169         /* If that is not enough, drop trailing null.  */
 170         tempLength -= len; /* easier to do checks */
 171         while (tempLength >= 0) {
 172                 if (tempString[0] != '0') {
 173                         if (!tempLength) {
 174                                 /* 1234 barely fits in 4 chars (w/o EOL '\0') */
 175                                 break;
 176                         }
 177                         /* 12345 doesn't fit into 4 chars */
 178                         return /*FALSE*/;
 179                 }
 180                 tempLength--; /* still have leading '0', */
 181                 tempString++; /* can afford to drop it but retain EOL '\0' */
 182         }
 183
 184         /* Copy the string to the field.  */
 185         memcpy(cp, tempString, len);
 186         /*return TRUE;*/
 187 }
 188
 189 /* Write out a tar header for the specified file/directory/whatever */
 190 void BUG_tar_header_size(void);
 191 static int writeTarHeader(struct TarBallInfo *tbInfo,
 192                 const char *header_name, const char *fileName, struct stat *statbuf)
 193 {
 194         struct TarHeader header;
 195         const unsigned char *cp;
 196         int chksum;
 197         int size;
 198
 199         if (sizeof(header) != 512)
 200                 BUG_tar_header_size();
 201
 202         bzero(&header, sizeof(struct TarHeader));
 203
 204         safe_strncpy(header.name, header_name, sizeof(header.name));
 205
 206         /* POSIX says to mask mode with 07777. */
 207         putOctal(header.mode, sizeof(header.mode), statbuf->st_mode & 07777);
 208         putOctal(header.uid, sizeof(header.uid), statbuf->st_uid);
 209         putOctal(header.gid, sizeof(header.gid), statbuf->st_gid);
 210         memset(header.size, '0', sizeof(header.size)-1); /* Regular file size is handled later */
 211         putOctal(header.mtime, sizeof(header.mtime), statbuf->st_mtime);
 212         strcpy(header.magic, "ustar  ");
 213
 214         /* Enter the user and group names */
 215         safe_strncpy(header.uname, get_cached_username(statbuf->st_uid), sizeof(header.uname));
 216         safe_strncpy(header.gname, get_cached_groupname(statbuf->st_gid), sizeof(header.gname));
 217
 218         if (tbInfo->hlInfo) {
 219                 /* This is a hard link */
 220                 header.typeflag = LNKTYPE;
 221                 strncpy(header.linkname, tbInfo->hlInfo->name,
 222                                 sizeof(header.linkname));
 223         } else if (S_ISLNK(statbuf->st_mode)) {
 224                 char *lpath = xreadlink(fileName);
 225                 if (!lpath)             /* Already printed err msg inside xreadlink() */
 226                         return FALSE;
 227                 header.typeflag = SYMTYPE;
 228                 strncpy(header.linkname, lpath, sizeof(header.linkname));
 229                 /* If it is larger than 100 bytes, bail out */
 230                 if (header.linkname[sizeof(header.linkname)-1] /* at least 100? */
 231                  && lpath[sizeof(header.linkname)] /* and 101th is also not zero */
 232                 ) {
 233                         free(lpath);
 234                         bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
 235                         return FALSE;
 236                 }
 237                 free(lpath);
 238         } else if (S_ISDIR(statbuf->st_mode)) {
 239                 header.typeflag = DIRTYPE;
 240                 strncat(header.name, "/", sizeof(header.name));
 241         } else if (S_ISCHR(statbuf->st_mode)) {
 242                 header.typeflag = CHRTYPE;
 243                 putOctal(header.devmajor, sizeof(header.devmajor),
 244                                  major(statbuf->st_rdev));
 245                 putOctal(header.devminor, sizeof(header.devminor),
 246                                  minor(statbuf->st_rdev));
 247         } else if (S_ISBLK(statbuf->st_mode)) {
 248                 header.typeflag = BLKTYPE;
 249                 putOctal(header.devmajor, sizeof(header.devmajor),
 250                                  major(statbuf->st_rdev));
 251                 putOctal(header.devminor, sizeof(header.devminor),
 252                                  minor(statbuf->st_rdev));
 253         } else if (S_ISFIFO(statbuf->st_mode)) {
 254                 header.typeflag = FIFOTYPE;
 255         } else if (S_ISREG(statbuf->st_mode)) {
 256                 header.typeflag = REGTYPE;
 257                 putOctal(header.size, sizeof(header.size), statbuf->st_size);
 258         } else {
 259                 bb_error_msg("%s: unknown file type", fileName);
 260                 return FALSE;
 261         }
 262
 263         /* Calculate and store the checksum (i.e., the sum of all of the bytes of
 264          * the header).  The checksum field must be filled with blanks for the
 265          * calculation.  The checksum field is formatted differently from the
 266          * other fields: it has [6] digits, a null, then a space -- rather than
 267          * digits, followed by a null like the other fields... */
 268         memset(header.chksum, ' ', sizeof(header.chksum));
 269         cp = (const unsigned char *) &header;
 270         chksum = 0;
 271         size = sizeof(struct TarHeader);
 272         do { chksum += *cp++; } while (--size);
 273         putOctal(header.chksum, sizeof(header.chksum)-1, chksum);
 274
 275         /* Now write the header out to disk */
 276         xwrite(tbInfo->tarFd, &header, sizeof(struct TarHeader));
 277
 278         /* Now do the verbose thing (or not) */
 279
 280         if (tbInfo->verboseFlag) {
 281                 FILE *vbFd = stdout;
 282
 283                 if (tbInfo->tarFd == STDOUT_FILENO)     /* If the archive goes to stdout, verbose to stderr */
 284                         vbFd = stderr;
 285
 286                 fprintf(vbFd, "%s\n", header.name);
 287         }
 288
 289         return TRUE;
 290 }
 291
 292 # if ENABLE_FEATURE_TAR_FROM
 293 static int exclude_file(const llist_t *excluded_files, const char *file)
 294 {
 295         while (excluded_files) {
 296                 if (excluded_files->data[0] == '/') {
 297                         if (fnmatch(excluded_files->data, file,
 298                                                 FNM_PATHNAME | FNM_LEADING_DIR) == 0)
 299                                 return 1;
 300                 } else {
 301                         const char *p;
 302
 303                         for (p = file; p[0] != '\0'; p++) {
 304                                 if ((p == file || p[-1] == '/') && p[0] != '/' &&
 305                                         fnmatch(excluded_files->data, p,
 306                                                         FNM_PATHNAME | FNM_LEADING_DIR) == 0)
 307                                         return 1;
 308                         }
 309                 }
 310                 excluded_files = excluded_files->link;
 311         }
 312
 313         return 0;
 314 }
 315 # else
 316 #define exclude_file(excluded_files, file) 0
 317 # endif
 318
 319 static int writeFileToTarball(const char *fileName, struct stat *statbuf,
 320                         void *userData, int depth)
 321 {
 322         struct TarBallInfo *tbInfo = (struct TarBallInfo *) userData;
 323         const char *header_name;
 324         int inputFileFd = -1;
 325
 326         /*
 327          * Check to see if we are dealing with a hard link.
 328          * If so -
 329          * Treat the first occurance of a given dev/inode as a file while
 330          * treating any additional occurances as hard links.  This is done
 331          * by adding the file information to the HardLinkInfo linked list.
 332          */
 333         tbInfo->hlInfo = NULL;
 334         if (statbuf->st_nlink > 1) {
 335                 tbInfo->hlInfo = findHardLinkInfo(tbInfo->hlInfoHead, statbuf);
 336                 if (tbInfo->hlInfo == NULL)
 337                         addHardLinkInfo(&tbInfo->hlInfoHead, statbuf, fileName);
 338         }
 339
 340         /* It is against the rules to archive a socket */
 341         if (S_ISSOCK(statbuf->st_mode)) {
 342                 bb_error_msg("%s: socket ignored", fileName);
 343                 return TRUE;
 344         }
 345
 346         /* It is a bad idea to store the archive we are in the process of creating,
 347          * so check the device and inode to be sure that this particular file isn't
 348          * the new tarball */
 349         if (tbInfo->statBuf.st_dev == statbuf->st_dev &&
 350                 tbInfo->statBuf.st_ino == statbuf->st_ino) {
 351                 bb_error_msg("%s: file is the archive; skipping", fileName);
 352                 return TRUE;
 353         }
 354
 355         header_name = fileName;
 356         while (header_name[0] == '/') {
 357                 static int alreadyWarned = FALSE;
 358
 359                 if (alreadyWarned == FALSE) {
 360                         bb_error_msg("removing leading '/' from member names");
 361                         alreadyWarned = TRUE;
 362                 }
 363                 header_name++;
 364         }
 365
 366         if (strlen(fileName) >= NAME_SIZE) {
 367                 bb_error_msg("names longer than "NAME_SIZE_STR" chars not supported");
 368                 return TRUE;
 369         }
 370
 371         if (header_name[0] == '\0')
 372                 return TRUE;
 373
 374         if (exclude_file(tbInfo->excludeList, header_name))
 375                 return SKIP;
 376
 377         /* Is this a regular file? */
 378         if (tbInfo->hlInfo == NULL && S_ISREG(statbuf->st_mode)) {
 379                 /* open the file we want to archive, and make sure all is well */
 380                 inputFileFd = open(fileName, O_RDONLY);
 381                 if (inputFileFd < 0) {
 382                         bb_perror_msg("%s: cannot open", fileName);
 383                         return FALSE;
 384                 }
 385         }
 386
 387         /* Add an entry to the tarball */
 388         if (writeTarHeader(tbInfo, header_name, fileName, statbuf) == FALSE) {
 389                 return FALSE;
 390         }
 391
 392         /* If it was a regular file, write out the body */
 393         if (inputFileFd >= 0) {
 394                 off_t readSize = 0;
 395
 396                 /* write the file to the archive */
 397                 readSize = bb_copyfd_size(inputFileFd, tbInfo->tarFd, statbuf->st_size);
 398                 if (readSize != statbuf->st_size) {
 399                         /* Deadly. We record size into header first, */
 400                         /* and then write out file. If file shrinks in between, */
 401                         /* tar will be corrupted. So bail out. */
 402                         /* NB: GNU tar 1.16 warns and pads with zeroes */
 403                         /* or even seeks back and updates header */
 404                         bb_error_msg_and_die("short read from %s, aborting", fileName);
 405                 }
 406                 /* Check that file did not grow in between? */
 407                 /* if (safe_read(inputFileFd,1) == 1) warn but continue? */
 408                 close(inputFileFd);
 409
 410                 /* Pad the file up to the tar block size */
 411                 /* (a few tricks here in the name of code size) */
 412                 readSize = (-(int)readSize) & (TAR_BLOCK_SIZE-1);
 413                 bzero(bb_common_bufsiz1, readSize);
 414                 xwrite(tbInfo->tarFd, bb_common_bufsiz1, readSize);
 415         }
 416
 417         return TRUE;
 418 }
 419
 420 static int writeTarFile(const int tar_fd, const int verboseFlag,
 421         const unsigned long dereferenceFlag, const llist_t *include,
 422         const llist_t *exclude, const int gzip)
 423 {
 424         pid_t gzipPid = 0;
 425         int errorFlag = FALSE;
 426         struct TarBallInfo tbInfo;
 427
 428         tbInfo.hlInfoHead = NULL;
 429
 430         fchmod(tar_fd, 0644);
 431         tbInfo.tarFd = tar_fd;
 432         tbInfo.verboseFlag = verboseFlag;
 433
 434         /* Store the stat info for the tarball's file, so
 435          * can avoid including the tarball into itself....  */
 436         if (fstat(tbInfo.tarFd, &tbInfo.statBuf) < 0)
 437                 bb_perror_msg_and_die("cannot stat tar file");
 438
 439         if ((ENABLE_FEATURE_TAR_GZIP || ENABLE_FEATURE_TAR_BZIP2) && gzip) {
 440                 int gzipDataPipe[2] = { -1, -1 };
 441                 int gzipStatusPipe[2] = { -1, -1 };
 442                 volatile int vfork_exec_errno = 0;
 443                 char *zip_exec = (gzip == 1) ? "gzip" : "bzip2";
 444
 445
 446                 if (pipe(gzipDataPipe) < 0 || pipe(gzipStatusPipe) < 0)
 447                         bb_perror_msg_and_die("pipe");
 448
 449                 signal(SIGPIPE, SIG_IGN);       /* we only want EPIPE on errors */
 450
 451 # if __GNUC__
 452                 /* Avoid vfork clobbering */
 453                 (void) &include;
 454                 (void) &errorFlag;
 455                 (void) &zip_exec;
 456 # endif
 457
 458                 gzipPid = vfork();
 459
 460                 if (gzipPid == 0) {
 461                         dup2(gzipDataPipe[0], 0);
 462                         close(gzipDataPipe[1]);
 463
 464                         dup2(tbInfo.tarFd, 1);
 465
 466                         close(gzipStatusPipe[0]);
 467                         fcntl(gzipStatusPipe[1], F_SETFD, FD_CLOEXEC);  /* close on exec shows success */
 468
 469                         execlp(zip_exec, zip_exec, "-f", NULL);
 470                         vfork_exec_errno = errno;
 471
 472                         close(gzipStatusPipe[1]);
 473                         exit(-1);
 474                 } else if (gzipPid > 0) {
 475                         close(gzipDataPipe[0]);
 476                         close(gzipStatusPipe[1]);
 477
 478                         while (1) {
 479                                 char buf;
 480
 481                                 int n = full_read(gzipStatusPipe[0], &buf, 1);
 482
 483                                 if (n == 0 && vfork_exec_errno != 0) {
 484                                         errno = vfork_exec_errno;
 485                                         bb_perror_msg_and_die("cannot exec %s", zip_exec);
 486                                 } else if ((n < 0) && (errno == EAGAIN || errno == EINTR))
 487                                         continue;       /* try it again */
 488                                 break;
 489                         }
 490                         close(gzipStatusPipe[0]);
 491
 492                         tbInfo.tarFd = gzipDataPipe[1];
 493                 } else bb_perror_msg_and_die("vfork gzip");
 494         }
 495
 496         tbInfo.excludeList = exclude;
 497
 498         /* Read the directory/files and iterate over them one at a time */
 499         while (include) {
 500                 if (!recursive_action(include->data, TRUE, dereferenceFlag,
 501                                 FALSE, writeFileToTarball, writeFileToTarball, &tbInfo, 0))
 502                 {
 503                         errorFlag = TRUE;
 504                 }
 505                 include = include->link;
 506         }
 507         /* Write two empty blocks to the end of the archive */
 508         bzero(bb_common_bufsiz1, 2*TAR_BLOCK_SIZE);
 509         xwrite(tbInfo.tarFd, bb_common_bufsiz1, 2*TAR_BLOCK_SIZE);
 510
 511         /* To be pedantically correct, we would check if the tarball
 512          * is smaller than 20 tar blocks, and pad it if it was smaller,
 513          * but that isn't necessary for GNU tar interoperability, and
 514          * so is considered a waste of space */
 515
 516         /* Close so the child process (if any) will exit */
 517         close(tbInfo.tarFd);
 518
 519         /* Hang up the tools, close up shop, head home */
 520         if (ENABLE_FEATURE_CLEAN_UP)
 521                 freeHardLinkInfo(&tbInfo.hlInfoHead);
 522
 523         if (errorFlag)
 524                 bb_error_msg("error exit delayed from previous errors");
 525
 526         if (gzipPid && waitpid(gzipPid, NULL, 0) == -1)
 527                 bb_error_msg("waitpid failed");
 528
 529         return !errorFlag;
 530 }
 531 #else
 532 int writeTarFile(const int tar_fd, const int verboseFlag,
 533         const unsigned long dereferenceFlag, const llist_t *include,
 534         const llist_t *exclude, const int gzip);
 535 #endif  /* tar_create */
 536
 537 #if ENABLE_FEATURE_TAR_FROM
 538 static llist_t *append_file_list_to_list(llist_t *list)
 539 {
 540         FILE *src_stream;
 541         llist_t *cur = list;
 542         llist_t *tmp;
 543         char *line;
 544         llist_t *newlist = NULL;
 545
 546         while (cur) {
 547                 src_stream = xfopen(cur->data, "r");
 548                 tmp = cur;
 549                 cur = cur->link;
 550                 free(tmp);
 551                 while ((line = xmalloc_getline(src_stream)) != NULL) {
 552                         char *filename_ptr = last_char_is(line, '/');
 553                         if (filename_ptr > line)
 554                                 *filename_ptr = '\0';
 555                         llist_add_to(&newlist, line);
 556                 }
 557                 fclose(src_stream);
 558         }
 559         return newlist;
 560 }
 561 #else
 562 #define append_file_list_to_list(x)     0
 563 #endif
 564
 565 #if ENABLE_FEATURE_TAR_COMPRESS
 566 static char get_header_tar_Z(archive_handle_t *archive_handle)
 567 {
 568         /* Can't lseek over pipes */
 569         archive_handle->seek = seek_by_read;
 570
 571         /* do the decompression, and cleanup */
 572         if (xread_char(archive_handle->src_fd) != 0x1f
 573          || xread_char(archive_handle->src_fd) != 0x9d
 574         ) {
 575                 bb_error_msg_and_die("invalid magic");
 576         }
 577
 578         archive_handle->src_fd = open_transformer(archive_handle->src_fd, uncompress);
 579         archive_handle->offset = 0;
 580         while (get_header_tar(archive_handle) == EXIT_SUCCESS)
 581                 /* nothing */;
 582
 583         /* Can only do one file at a time */
 584         return EXIT_FAILURE;
 585 }
 586 #else
 587 #define get_header_tar_Z        0
 588 #endif
 589
 590 enum {
 591         OPTBIT_KEEP_OLD = 7,
 592         USE_FEATURE_TAR_CREATE(  OPTBIT_CREATE      ,)
 593         USE_FEATURE_TAR_CREATE(  OPTBIT_DEREFERENCE ,)
 594         USE_FEATURE_TAR_BZIP2(   OPTBIT_BZIP2       ,)
 595         USE_FEATURE_TAR_LZMA(    OPTBIT_LZMA        ,)
 596         USE_FEATURE_TAR_FROM(    OPTBIT_INCLUDE_FROM,)
 597         USE_FEATURE_TAR_FROM(    OPTBIT_EXCLUDE_FROM,)
 598         USE_FEATURE_TAR_GZIP(    OPTBIT_GZIP        ,)
 599         USE_FEATURE_TAR_COMPRESS(OPTBIT_COMPRESS    ,)
 600         OPTBIT_NOPRESERVE_OWN,
 601         OPTBIT_NOPRESERVE_PERM,
 602         OPT_TEST         = 1 << 0, // t
 603         OPT_EXTRACT      = 1 << 1, // x
 604         OPT_BASEDIR      = 1 << 2, // C
 605         OPT_TARNAME      = 1 << 3, // f
 606         OPT_2STDOUT      = 1 << 4, // O
 607         OPT_P            = 1 << 5, // p
 608         OPT_VERBOSE      = 1 << 6, // v
 609         OPT_KEEP_OLD     = 1 << 7, // k
 610         OPT_CREATE       = USE_FEATURE_TAR_CREATE(  (1<<OPTBIT_CREATE      )) + 0, // c
 611         OPT_DEREFERENCE  = USE_FEATURE_TAR_CREATE(  (1<<OPTBIT_DEREFERENCE )) + 0, // h
 612         OPT_BZIP2        = USE_FEATURE_TAR_BZIP2(   (1<<OPTBIT_BZIP2       )) + 0, // j
 613         OPT_LZMA         = USE_FEATURE_TAR_LZMA(    (1<<OPTBIT_LZMA        )) + 0, // a
 614         OPT_INCLUDE_FROM = USE_FEATURE_TAR_FROM(    (1<<OPTBIT_INCLUDE_FROM)) + 0, // T
 615         OPT_EXCLUDE_FROM = USE_FEATURE_TAR_FROM(    (1<<OPTBIT_EXCLUDE_FROM)) + 0, // X
 616         OPT_GZIP         = USE_FEATURE_TAR_GZIP(    (1<<OPTBIT_GZIP        )) + 0, // z
 617         OPT_COMPRESS     = USE_FEATURE_TAR_COMPRESS((1<<OPTBIT_COMPRESS    )) + 0, // Z
 618         OPT_NOPRESERVE_OWN  = 1 << OPTBIT_NOPRESERVE_OWN , // no-same-owner
 619         OPT_NOPRESERVE_PERM = 1 << OPTBIT_NOPRESERVE_PERM, // no-same-permissions
 620 };
 621 #if ENABLE_FEATURE_TAR_LONG_OPTIONS
 622 static const struct option tar_long_options[] = {
 623         { "list",               0,  NULL,   't' },
 624         { "extract",            0,  NULL,   'x' },
 625         { "directory",          1,  NULL,   'C' },
 626         { "file",               1,  NULL,   'f' },
 627         { "to-stdout",          0,  NULL,   'O' },
 628         { "same-permissions",   0,  NULL,   'p' },
 629         { "verbose",            0,  NULL,   'v' },
 630         { "keep-old",           0,  NULL,   'k' },
 631 # if ENABLE_FEATURE_TAR_CREATE
 632         { "create",             0,  NULL,   'c' },
 633         { "dereference",        0,  NULL,   'h' },
 634 # endif
 635 # if ENABLE_FEATURE_TAR_BZIP2
 636         { "bzip2",              0,  NULL,   'j' },
 637 # endif
 638 # if ENABLE_FEATURE_TAR_LZMA
 639         { "lzma",               0,  NULL,   'a' },
 640 # endif
 641 # if ENABLE_FEATURE_TAR_FROM
 642         { "files-from",         1,  NULL,   'T' },
 643         { "exclude-from",       1,  NULL,   'X' },
 644         { "exclude",            1,  NULL,   0xfd },
 645 # endif
 646 # if ENABLE_FEATURE_TAR_GZIP
 647         { "gzip",               0,  NULL,   'z' },
 648 # endif
 649 # if ENABLE_FEATURE_TAR_COMPRESS
 650         { "compress",           0,  NULL,   'Z' },
 651 # endif
 652         { "no-same-owner",      0,  NULL,   0xfe },
 653         { "no-same-permissions",0,  NULL,   0xff },
 654         { 0,                    0, 0, 0 }
 655 };
 656 #else
 657 #define tar_long_options        0
 658 #endif
 659
 660 int tar_main(int argc, char **argv)
 661 {
 662         char (*get_header_ptr)(archive_handle_t *) = get_header_tar;
 663         archive_handle_t *tar_handle;
 664         char *base_dir = NULL;
 665         const char *tar_filename = "-";
 666         unsigned opt;
 667         llist_t *excludes = NULL;
 668
 669         /* Initialise default values */
 670         tar_handle = init_handle();
 671         tar_handle->flags = ARCHIVE_CREATE_LEADING_DIRS
 672                           | ARCHIVE_PRESERVE_DATE
 673                           | ARCHIVE_EXTRACT_UNCONDITIONAL;
 674
 675         /* Prepend '-' to the first argument if required */
 676         opt_complementary = "--:" // first arg is options
 677                 "?:" // bail out with usage instead of error return
 678                 "X::T::" // cumulative lists
 679                 "\xfd::" // cumulative lists for --exclude
 680                 USE_FEATURE_TAR_CREATE("c:") "t:x:" // at least one of these is reqd
 681                 USE_FEATURE_TAR_CREATE("c--tx:t--cx:x--ct") // mutually exclusive
 682                 SKIP_FEATURE_TAR_CREATE("t--x:x--t"); // mutually exclusive
 683         if (ENABLE_FEATURE_TAR_LONG_OPTIONS)
 684                 applet_long_options = tar_long_options;
 685         opt = getopt32(argc, argv,
 686                 "txC:f:Opvk"
 687                 USE_FEATURE_TAR_CREATE(  "ch"  )
 688                 USE_FEATURE_TAR_BZIP2(   "j"   )
 689                 USE_FEATURE_TAR_LZMA(    "a"   )
 690                 USE_FEATURE_TAR_FROM(    "T:X:")
 691                 USE_FEATURE_TAR_GZIP(    "z"   )
 692                 USE_FEATURE_TAR_COMPRESS("Z"   )
 693                 ,
 694                 &base_dir, // -C dir
 695                 &tar_filename, // -f filename
 696                 USE_FEATURE_TAR_FROM(&(tar_handle->accept),) // T
 697                 USE_FEATURE_TAR_FROM(&(tar_handle->reject),) // X
 698                 USE_FEATURE_TAR_FROM(&excludes             ) // --exclude
 699                 );
 700
 701         if (opt & OPT_TEST) {
 702                 if (tar_handle->action_header == header_list
 703                  || tar_handle->action_header == header_verbose_list
 704                 ) {
 705                         tar_handle->action_header = header_verbose_list;
 706                 } else
 707                         tar_handle->action_header = header_list;
 708         }
 709         if ((opt & OPT_EXTRACT) && tar_handle->action_data != data_extract_to_stdout)
 710                 tar_handle->action_data = data_extract_all;
 711
 712         if (opt & OPT_2STDOUT)
 713                 tar_handle->action_data = data_extract_to_stdout;
 714
 715         if (opt & OPT_VERBOSE) {
 716                 if (tar_handle->action_header == header_list
 717                  || tar_handle->action_header == header_verbose_list
 718                 ) {
 719                         tar_handle->action_header = header_verbose_list;
 720                 } else
 721                         tar_handle->action_header = header_list;
 722         }
 723         if (opt & OPT_KEEP_OLD)
 724                 tar_handle->flags &= ~ARCHIVE_EXTRACT_UNCONDITIONAL;
 725
 726         if (opt & OPT_NOPRESERVE_OWN)
 727                 tar_handle->flags |= ARCHIVE_NOPRESERVE_OWN;
 728
 729         if (opt & OPT_NOPRESERVE_PERM)
 730                 tar_handle->flags |= ARCHIVE_NOPRESERVE_PERM;
 731
 732         if (opt & OPT_GZIP)
 733                 get_header_ptr = get_header_tar_gz;
 734
 735         if (opt & OPT_BZIP2)
 736                 get_header_ptr = get_header_tar_bz2;
 737
 738         if (opt & OPT_LZMA)
 739                 get_header_ptr = get_header_tar_lzma;
 740
 741         if (opt & OPT_COMPRESS)
 742                 get_header_ptr = get_header_tar_Z;
 743
 744         if (ENABLE_FEATURE_TAR_FROM) {
 745                 tar_handle->reject = append_file_list_to_list(tar_handle->reject);
 746                 /* Append excludes to reject */
 747                 while (excludes) {
 748                         llist_t *temp = excludes->link;
 749                         excludes->link = tar_handle->reject;
 750                         tar_handle->reject = excludes;
 751                         excludes = temp;
 752                 }
 753                 tar_handle->accept = append_file_list_to_list(tar_handle->accept);
 754         }
 755
 756         /* Check if we are reading from stdin */
 757         if (argv[optind] && *argv[optind] == '-') {
 758                 /* Default is to read from stdin, so just skip to next arg */
 759                 optind++;
 760         }
 761
 762         /* Setup an array of filenames to work with */
 763         /* TODO: This is the same as in ar, separate function ? */
 764         while (optind < argc) {
 765                 char *filename_ptr = last_char_is(argv[optind], '/');
 766                 if (filename_ptr > argv[optind])
 767                         *filename_ptr = '\0';
 768
 769                 llist_add_to(&(tar_handle->accept), argv[optind]);
 770                 optind++;
 771         }
 772
 773         if (tar_handle->accept || tar_handle->reject)
 774                 tar_handle->filter = filter_accept_reject_list;
 775
 776         /* Open the tar file */
 777         {
 778                 FILE *tar_stream;
 779                 int flags;
 780
 781                 if (opt & OPT_CREATE) {
 782                         /* Make sure there is at least one file to tar up.  */
 783                         if (tar_handle->accept == NULL)
 784                                 bb_error_msg_and_die("empty archive");
 785
 786                         tar_stream = stdout;
 787                         /* Mimicking GNU tar 1.15.1: */
 788                         flags = O_WRONLY|O_CREAT|O_TRUNC;
 789                 /* was doing unlink; open(O_WRONLY|O_CREAT|O_EXCL); why? */
 790                 } else {
 791                         tar_stream = stdin;
 792                         flags = O_RDONLY;
 793                 }
 794
 795                 if (tar_filename[0] == '-' && !tar_filename[1]) {
 796                         tar_handle->src_fd = fileno(tar_stream);
 797                         tar_handle->seek = seek_by_read;
 798                 } else {
 799                         tar_handle->src_fd = xopen3(tar_filename, flags, 0666);
 800                 }
 801         }
 802
 803         if (base_dir)
 804                 xchdir(base_dir);
 805
 806         /* create an archive */
 807         if (opt & OPT_CREATE) {
 808                 int verboseFlag = FALSE;
 809                 int zipMode = 0;
 810
 811                 if (ENABLE_FEATURE_TAR_GZIP && get_header_ptr == get_header_tar_gz)
 812                         zipMode = 1;
 813                 if (ENABLE_FEATURE_TAR_BZIP2 && get_header_ptr == get_header_tar_bz2)
 814                         zipMode = 2;
 815
 816                 if (tar_handle->action_header == header_list
 817                  || tar_handle->action_header == header_verbose_list
 818                 ) {
 819                         verboseFlag = TRUE;
 820                 }
 821                 writeTarFile(tar_handle->src_fd, verboseFlag, opt & OPT_DEREFERENCE,
 822                                 tar_handle->accept,
 823                         tar_handle->reject, zipMode);
 824                 /* NB: writeTarFile() closes tar_handle->src_fd */
 825                 return EXIT_SUCCESS;
 826         }
 827
 828         while (get_header_ptr(tar_handle) == EXIT_SUCCESS)
 829                 /* nothing */;
 830
 831         /* Check that every file that should have been extracted was */
 832         while (tar_handle->accept) {
 833                 if (!find_list_entry(tar_handle->reject, tar_handle->accept->data)
 834                  && !find_list_entry(tar_handle->passed, tar_handle->accept->data)
 835                 ) {
 836                         bb_error_msg_and_die("%s: not found in archive",
 837                                 tar_handle->accept->data);
 838                 }
 839                 tar_handle->accept = tar_handle->accept->link;
 840         }
 841         if (ENABLE_FEATURE_CLEAN_UP /* && tar_handle->src_fd != STDIN_FILENO */)
 842                 close(tar_handle->src_fd);
 843
 844         return EXIT_SUCCESS;
 845 }