tar.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini tar implementation for busybox
   4  *
   5  * Note, that as of BusyBox-0.43, tar has been completely rewritten from the
   6  * ground up.  It still has remnents of the old code lying about, but it is
   7  * very different now (i.e. cleaner, less global variables, etc)
   8  *
   9  * Copyright (C) 2000 by Lineo, inc.
  10  * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
  11  *
  12  * Based in part in the tar implementation in sash
  13  *  Copyright (c) 1999 by David I. Bell
  14  *  Permission is granted to use, distribute, or modify this source,
  15  *  provided that this copyright notice remains intact.
  16  *  Permission to distribute sash derived code under the GPL has been granted.
  17  *
  18  * Based in part on the tar implementation from busybox-0.28
  19  *  Copyright (C) 1995 Bruce Perens
  20  *  This is free software under the GNU General Public License.
  21  *
  22  * This program is free software; you can redistribute it and/or modify
  23  * it under the terms of the GNU General Public License as published by
  24  * the Free Software Foundation; either version 2 of the License, or
  25  * (at your option) any later version.
  26  *
  27  * This program is distributed in the hope that it will be useful,
  28  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  29  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  30  * General Public License for more details.
  31  *
  32  * You should have received a copy of the GNU General Public License
  33  * along with this program; if not, write to the Free Software
  34  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  35  *
  36  */
  37
  38
  39 #include "internal.h"
  40 #define BB_DECLARE_EXTERN
  41 #define bb_need_io_error
  42 #include "messages.c"
  43 #include <stdio.h>
  44 #include <dirent.h>
  45 #include <errno.h>
  46 #include <fcntl.h>
  47 #include <signal.h>
  48 #include <time.h>
  49 #include <utime.h>
  50 #include <sys/types.h>
  51 #include <sys/sysmacros.h>
  52 #include <getopt.h>
  53
  54 /* Tar file constants  */
  55 #ifndef MAJOR
  56 #define MAJOR(dev) (((dev)>>8)&0xff)
  57 #define MINOR(dev) ((dev)&0xff)
  58 #endif
  59
  60
  61 /* POSIX tar Header Block, from POSIX 1003.1-1990  */
  62 struct TarHeader
  63 {
  64                                 /* byte offset */
  65         char name[100];               /*   0-99 */
  66         char mode[8];                 /* 100-107 */
  67         char uid[8];                  /* 108-115 */
  68         char gid[8];                  /* 116-123 */
  69         char size[12];                /* 124-135 */
  70         char mtime[12];               /* 136-147 */
  71         char chksum[8];               /* 148-155 */
  72         char typeflag;                /* 156-156 */
  73         char linkname[100];           /* 157-256 */
  74         char magic[6];                /* 257-262 */
  75         char version[2];              /* 263-264 */
  76         char uname[32];               /* 265-296 */
  77         char gname[32];               /* 297-328 */
  78         char devmajor[8];             /* 329-336 */
  79         char devminor[8];             /* 337-344 */
  80         char prefix[155];             /* 345-499 */
  81         char padding[12];             /* 500-512 (pad to exactly the TAR_BLOCK_SIZE) */
  82 };
  83 typedef struct TarHeader TarHeader;
  84
  85
  86 /* A few useful constants */
  87 #define TAR_MAGIC          "ustar"        /* ustar and a null */
  88 #define TAR_VERSION        "  "           /* Be compatable with GNU tar format */
  89 #define TAR_MAGIC_LEN       6
  90 #define TAR_VERSION_LEN     2
  91 #define TAR_BLOCK_SIZE      512
  92
  93 /* A nice enum with all the possible tar file content types */
  94 enum TarFileType
  95 {
  96         REGTYPE  = '0',            /* regular file */
  97         REGTYPE0 = '\0',           /* regular file (ancient bug compat)*/
  98         LNKTYPE  = '1',            /* hard link */
  99         SYMTYPE  = '2',            /* symbolic link */
 100         CHRTYPE  = '3',            /* character special */
 101         BLKTYPE  = '4',            /* block special */
 102         DIRTYPE  = '5',            /* directory */
 103         FIFOTYPE = '6',            /* FIFO special */
 104         CONTTYPE = '7',            /* reserved */
 105 };
 106 typedef enum TarFileType TarFileType;
 107
 108 /* This struct ignores magic, non-numeric user name,
 109  * non-numeric group name, and the checksum, since
 110  * these are all ignored by BusyBox tar. */
 111 struct TarInfo
 112 {
 113         int              tarFd;          /* An open file descriptor for reading from the tarball */
 114         char *           name;           /* File name */
 115         mode_t           mode;           /* Unix mode, including device bits. */
 116         uid_t            uid;            /* Numeric UID */
 117         gid_t            gid;            /* Numeric GID */
 118         size_t           size;           /* Size of file */
 119         time_t           mtime;          /* Last-modified time */
 120         enum TarFileType type;           /* Regular, directory, link, etc */
 121         char *           linkname;       /* Name for symbolic and hard links */
 122         long             devmajor;       /* Major number for special device */
 123         long             devminor;       /* Minor number for special device */
 124 };
 125 typedef struct TarInfo TarInfo;
 126
 127 /* Local procedures to restore files from a tar file.  */
 128 static int readTarFile(const char* tarName, int extractFlag, int listFlag,
 129                 int tostdoutFlag, int verboseFlag, char** extractList,
 130                 char** excludeList);
 131
 132
 133
 134 #ifdef BB_FEATURE_TAR_CREATE
 135 /* Local procedures to save files into a tar file.  */
 136 static int writeTarFile(const char* tarName, int tostdoutFlag,
 137                 int verboseFlag, int argc, char **argv, char** excludeList);
 138 #endif
 139
 140 static struct option longopts[] =
 141 {
 142 #ifdef BB_FEATURE_TAR_EXCLUDE
 143         {"exclude",required_argument,NULL,'e'},
 144 #endif
 145                 {NULL,0,NULL,0}
 146 };
 147
 148 extern int tar_main(int argc, char **argv)
 149 {
 150         char** excludeList=NULL;
 151 #if defined BB_FEATURE_TAR_EXCLUDE
 152         int excludeListSize=0;
 153 #endif
 154         const char *tarName="-";
 155         int listFlag     = FALSE;
 156         int extractFlag  = FALSE;
 157         int createFlag   = FALSE;
 158         int verboseFlag  = FALSE;
 159         int tostdoutFlag = FALSE;
 160         int opt;
 161
 162         if (argc <= 1)
 163                 usage(tar_usage);
 164
 165         /* do normal option parsing */
 166         while ((opt = getopt_long(argc, argv, "cxtvOf:", longopts, NULL)) != EOF) {
 167                 switch (opt) {
 168                                 case 'c':
 169                                         if (extractFlag == TRUE || listFlag == TRUE)
 170                                                 goto flagError;
 171                                         createFlag = TRUE;
 172                                         break;
 173                                 case 'x':
 174                                         if (listFlag == TRUE || createFlag == TRUE)
 175                                                 goto flagError;
 176                                         extractFlag = TRUE;
 177                                         break;
 178                                 case 't':
 179                                         if (extractFlag == TRUE || createFlag == TRUE)
 180                                                 goto flagError;
 181                                         listFlag = TRUE;
 182                                         break;
 183                                 case 'v':
 184                                         verboseFlag = TRUE;
 185                                         break;
 186                                 case 'O':
 187                                         tostdoutFlag = TRUE;
 188                                         tarName = "-";
 189                                         break;
 190                                 case 'f':
 191                                         if (*tarName != '-')
 192                                                 fatalError( "Only one 'f' option allowed\n");
 193                                         tarName = optarg;
 194                                         if (!strcmp(tarName, "-") && createFlag == TRUE)
 195                                                 tostdoutFlag = TRUE;
 196                                         break;
 197 #if defined BB_FEATURE_TAR_EXCLUDE
 198                                 case 'e':
 199                                         excludeList=xrealloc( excludeList, sizeof(char**) * (excludeListSize+2));
 200                                         excludeList[excludeListSize] = optarg;
 201                                         /* Remove leading "/"s */
 202                                         if (*excludeList[excludeListSize] =='/')
 203                                                 excludeList[excludeListSize] = (excludeList[excludeListSize])+1;
 204                                         /* Tack a NULL onto the end of the list */
 205                                         excludeList[++excludeListSize] = NULL;
 206                                         break;
 207 #endif
 208                                 default:
 209                                         usage(tar_usage);
 210                 }
 211         }
 212
 213         /*
 214          * Do the correct type of action supplying the rest of the
 215          * command line arguments as the list of files to process.
 216          */
 217         if (createFlag == TRUE) {
 218 #ifndef BB_FEATURE_TAR_CREATE
 219                 fatalError( "This version of tar was not compiled with tar creation support.\n");
 220 #else
 221                 exit(writeTarFile(tarName, tostdoutFlag, verboseFlag, argc-optind, &argv[optind], excludeList));
 222 #endif
 223         }
 224         if (listFlag == TRUE || extractFlag == TRUE) {
 225                 exit(readTarFile(tarName, extractFlag, listFlag, tostdoutFlag, verboseFlag, &argv[optind], excludeList));
 226         }
 227
 228   flagError:
 229         fatalError( "Exactly one of 'c', 'x' or 't' must be specified\n");
 230 }
 231
 232 static void
 233 fixUpPermissions(TarInfo *header)
 234 {
 235         struct utimbuf t;
 236         /* Now set permissions etc for the new file */
 237         chown(header->name, header->uid, header->gid);
 238         chmod(header->name, header->mode);
 239         /* Reset the time */
 240         t.actime = time(0);
 241         t.modtime = header->mtime;
 242         utime(header->name, &t);
 243 }
 244
 245 static int
 246 tarExtractRegularFile(TarInfo *header, int extractFlag, int tostdoutFlag)
 247 {
 248         size_t  writeSize;
 249         size_t  readSize;
 250         size_t  actualWriteSz;
 251         char    buffer[BUFSIZ];
 252         size_t  size = header->size;
 253         int outFd=fileno(stdout);
 254
 255         /* Open the file to be written, if a file is supposed to be written */
 256         if (extractFlag==TRUE && tostdoutFlag==FALSE) {
 257                 /* Create the path to the file, just in case it isn't there...
 258                  * This should not screw up path permissions or anything. */
 259                 createPath(header->name, 0777);
 260                 if ((outFd=open(header->name, O_CREAT|O_TRUNC|O_WRONLY,
 261                                                 header->mode & ~S_IFMT)) < 0) {
 262                         errorMsg(io_error, header->name, strerror(errno));
 263                         return( FALSE);
 264                 }
 265         }
 266
 267         /* Write out the file, if we are supposed to be doing that */
 268         while ( size > 0 ) {
 269                 actualWriteSz=0;
 270                 if ( size > sizeof(buffer) )
 271                         writeSize = readSize = sizeof(buffer);
 272                 else {
 273                         int mod = size % 512;
 274                         if ( mod != 0 )
 275                                 readSize = size + (512 - mod);
 276                         else
 277                                 readSize = size;
 278                         writeSize = size;
 279                 }
 280                 if ( (readSize = fullRead(header->tarFd, buffer, readSize)) <= 0 ) {
 281                         /* Tarball seems to have a problem */
 282                         errorMsg("Unexpected EOF in archive\n");
 283                         return( FALSE);
 284                 }
 285                 if ( readSize < writeSize )
 286                         writeSize = readSize;
 287
 288                 /* Write out the file, if we are supposed to be doing that */
 289                 if (extractFlag==TRUE) {
 290
 291                         if ((actualWriteSz=fullWrite(outFd, buffer, writeSize)) != writeSize ) {
 292                                 /* Output file seems to have a problem */
 293                                 errorMsg(io_error, header->name, strerror(errno));
 294                                 return( FALSE);
 295                         }
 296                 } else {
 297                         actualWriteSz=writeSize;
 298                 }
 299
 300                 size -= actualWriteSz;
 301         }
 302
 303         /* Now we are done writing the file out, so try
 304          * and fix up the permissions and whatnot */
 305         if (extractFlag==TRUE && tostdoutFlag==FALSE) {
 306                 close(outFd);
 307                 fixUpPermissions(header);
 308         }
 309         return( TRUE);
 310 }
 311
 312 static int
 313 tarExtractDirectory(TarInfo *header, int extractFlag, int tostdoutFlag)
 314 {
 315
 316         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 317                 return( TRUE);
 318
 319         if (createPath(header->name, header->mode) != TRUE) {
 320                 errorMsg("%s: Cannot mkdir: %s\n",
 321                                 header->name, strerror(errno));
 322                 return( FALSE);
 323         }
 324         /* make the final component, just in case it was
 325          * omitted by createPath() (which will skip the
 326          * directory if it doesn't have a terminating '/') */
 327         if (mkdir(header->name, header->mode) == 0) {
 328                 fixUpPermissions(header);
 329         }
 330         return( TRUE);
 331 }
 332
 333 static int
 334 tarExtractHardLink(TarInfo *header, int extractFlag, int tostdoutFlag)
 335 {
 336         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 337                 return( TRUE);
 338
 339         if (link(header->linkname, header->name) < 0) {
 340                 errorMsg("%s: Cannot create hard link to '%s': %s\n",
 341                                 header->name, header->linkname, strerror(errno));
 342                 return( FALSE);
 343         }
 344
 345         /* Now set permissions etc for the new directory */
 346         fixUpPermissions(header);
 347         return( TRUE);
 348 }
 349
 350 static int
 351 tarExtractSymLink(TarInfo *header, int extractFlag, int tostdoutFlag)
 352 {
 353         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 354                 return( TRUE);
 355
 356 #ifdef  S_ISLNK
 357         if (symlink(header->linkname, header->name) < 0) {
 358                 errorMsg("%s: Cannot create symlink to '%s': %s\n",
 359                                 header->name, header->linkname, strerror(errno));
 360                 return( FALSE);
 361         }
 362         /* Try to change ownership of the symlink.
 363          * If libs doesn't support that, don't bother.
 364          * Changing the pointed-to-file is the Wrong Thing(tm).
 365          */
 366 #if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
 367         lchown(header->name, header->uid, header->gid);
 368 #endif
 369
 370         /* Do not change permissions or date on symlink,
 371          * since it changes the pointed to file instead.  duh. */
 372 #else
 373         errorMsg("%s: Cannot create symlink to '%s': %s\n",
 374                         header->name, header->linkname,
 375                         "symlinks not supported");
 376 #endif
 377         return( TRUE);
 378 }
 379
 380 static int
 381 tarExtractSpecial(TarInfo *header, int extractFlag, int tostdoutFlag)
 382 {
 383         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 384                 return( TRUE);
 385
 386         if (S_ISCHR(header->mode) || S_ISBLK(header->mode) || S_ISSOCK(header->mode)) {
 387                 if (mknod(header->name, header->mode, makedev(header->devmajor, header->devminor)) < 0) {
 388                         errorMsg("%s: Cannot mknod: %s\n",
 389                                 header->name, strerror(errno));
 390                         return( FALSE);
 391                 }
 392         } else if (S_ISFIFO(header->mode)) {
 393                 if (mkfifo(header->name, header->mode) < 0) {
 394                         errorMsg("%s: Cannot mkfifo: %s\n",
 395                                 header->name, strerror(errno));
 396                         return( FALSE);
 397                 }
 398         }
 399
 400         /* Now set permissions etc for the new directory */
 401         fixUpPermissions(header);
 402         return( TRUE);
 403 }
 404
 405 /* Read an octal value in a field of the specified width, with optional
 406  * spaces on both sides of the number and with an optional null character
 407  * at the end.  Returns -1 on an illegal format.  */
 408 static long getOctal(const char *cp, int size)
 409 {
 410         long val = 0;
 411
 412         for(;(size > 0) && (*cp == ' '); cp++, size--);
 413         if ((size == 0) || !isOctal(*cp))
 414                 return -1;
 415         for(; (size > 0) && isOctal(*cp); size--) {
 416                 val = val * 8 + *cp++ - '0';
 417         }
 418         for (;(size > 0) && (*cp == ' '); cp++, size--);
 419         if ((size > 0) && *cp)
 420                 return -1;
 421         return val;
 422 }
 423
 424
 425 /* Parse the tar header and fill in the nice struct with the details */
 426 static int
 427 readTarHeader(struct TarHeader *rawHeader, struct TarInfo *header)
 428 {
 429         int i;
 430         long chksum, sum=0;
 431         unsigned char *s = (unsigned char *)rawHeader;
 432
 433         header->name  = rawHeader->name;
 434         /* Check for and relativify any absolute paths */
 435         if ( *(header->name) == '/' ) {
 436                 static int alreadyWarned=FALSE;
 437
 438                 while (*(header->name) == '/')
 439                         ++*(header->name);
 440
 441                 if (alreadyWarned == FALSE) {
 442                         errorMsg("Removing leading '/' from member names\n");
 443                         alreadyWarned = TRUE;
 444                 }
 445         }
 446
 447         header->mode  = getOctal(rawHeader->mode, sizeof(rawHeader->mode));
 448         header->uid   =  getOctal(rawHeader->uid, sizeof(rawHeader->uid));
 449         header->gid   =  getOctal(rawHeader->gid, sizeof(rawHeader->gid));
 450         header->size  = getOctal(rawHeader->size, sizeof(rawHeader->size));
 451         header->mtime = getOctal(rawHeader->mtime, sizeof(rawHeader->mtime));
 452         chksum = getOctal(rawHeader->chksum, sizeof(rawHeader->chksum));
 453         header->type  = rawHeader->typeflag;
 454         header->linkname  = rawHeader->linkname;
 455         header->devmajor  = getOctal(rawHeader->devmajor, sizeof(rawHeader->devmajor));
 456         header->devminor  = getOctal(rawHeader->devminor, sizeof(rawHeader->devminor));
 457
 458         /* Check the checksum */
 459         for (i = sizeof(*rawHeader); i-- != 0;) {
 460                 sum += *s++;
 461         }
 462         /* Remove the effects of the checksum field (replace
 463          * with blanks for the purposes of the checksum) */
 464         s = rawHeader->chksum;
 465         for (i = sizeof(rawHeader->chksum) ; i-- != 0;) {
 466                 sum -= *s++;
 467         }
 468         sum += ' ' * sizeof(rawHeader->chksum);
 469         if (sum == chksum )
 470                 return ( TRUE);
 471         return( FALSE);
 472 }
 473
 474
 475 /*
 476  * Read a tar file and extract or list the specified files within it.
 477  * If the list is empty than all files are extracted or listed.
 478  */
 479 static int readTarFile(const char* tarName, int extractFlag, int listFlag,
 480                 int tostdoutFlag, int verboseFlag, char** extractList,
 481                 char** excludeList)
 482 {
 483         int status, tarFd=-1;
 484         int errorFlag=FALSE;
 485         TarHeader rawHeader;
 486         TarInfo header;
 487         char** tmpList;
 488
 489         /* Open the tar file for reading.  */
 490         if (!strcmp(tarName, "-"))
 491                 tarFd = fileno(stdin);
 492         else
 493                 tarFd = open(tarName, O_RDONLY);
 494         if (tarFd < 0) {
 495                 errorMsg( "Error opening '%s': %s\n", tarName, strerror(errno));
 496                 return ( FALSE);
 497         }
 498
 499         /* Set the umask for this process so it doesn't
 500          * screw up permission setting for us later. */
 501         umask(0);
 502
 503         /* Read the tar file, and iterate over it one file at a time */
 504         while ( (status = fullRead(tarFd, (char*)&rawHeader, TAR_BLOCK_SIZE)) == TAR_BLOCK_SIZE ) {
 505
 506                 /* First, try to read the header */
 507                 if ( readTarHeader(&rawHeader, &header) == FALSE ) {
 508                         if ( *(header.name) == '\0' ) {
 509                                 goto endgame;
 510                         } else {
 511                                 errorFlag=TRUE;
 512                                 errorMsg("Bad tar header, skipping\n");
 513                                 continue;
 514                         }
 515                 }
 516                 if ( *(header.name) == '\0' )
 517                                 goto endgame;
 518                 header.tarFd = tarFd;
 519
 520 #if defined BB_FEATURE_TAR_EXCLUDE
 521                 {
 522                         int skipFlag=FALSE;
 523                         /* Check for excluded files....  */
 524                         for (tmpList=excludeList; tmpList && *tmpList; tmpList++) {
 525                                 /* Do some extra hoop jumping for when directory names
 526                                  * end in '/' but the entry in tmpList doesn't */
 527                                 if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
 528                                                         header.name[strlen(header.name)-1]=='/'
 529                                                         && strncmp( *tmpList, header.name,
 530                                                                 MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
 531                                         /* If it is a regular file, pretend to extract it with
 532                                          * the extractFlag set to FALSE, so the junk in the tarball
 533                                          * is properly skipped over */
 534                                         if ( header.type==REGTYPE || header.type==REGTYPE0 ) {
 535                                                         tarExtractRegularFile(&header, FALSE, FALSE);
 536                                         }
 537                                         skipFlag=TRUE;
 538                                         break;
 539                                 }
 540                         }
 541                         /* There are not the droids you're looking for, move along */
 542                         if (skipFlag==TRUE)
 543                                 continue;
 544                 }
 545 #endif
 546                 if (*extractList != NULL) {
 547                         int skipFlag = TRUE;
 548                         for (tmpList = extractList; *tmpList != NULL; tmpList++) {
 549                                 if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
 550                                                         header.name[strlen(header.name)-1]=='/'
 551                                                         && strncmp( *tmpList, header.name,
 552                                                                 MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
 553                                         /* If it is a regular file, pretend to extract it with
 554                                          * the extractFlag set to FALSE, so the junk in the tarball
 555                                          * is properly skipped over */
 556                                         skipFlag = FALSE;
 557                                         break;
 558                                 }
 559                         }
 560                         /* There are not the droids you're looking for, move along */
 561                         if (skipFlag == TRUE) {
 562                                 if ( header.type==REGTYPE || header.type==REGTYPE0 )
 563                                                 tarExtractRegularFile(&header, FALSE, FALSE);
 564                                 continue;
 565                         }
 566                 }
 567
 568                 if (listFlag == TRUE) {
 569                         /* Special treatment if the list (-t) flag is on */
 570                         if (verboseFlag == TRUE) {
 571                                 int len, len1;
 572                                 char buf[35];
 573                                 struct tm *tm = localtime (&(header.mtime));
 574
 575                                 len=printf("%s ", modeString(header.mode));
 576                                 memset(buf, 0, 8*sizeof(char));
 577                                 my_getpwuid(buf, header.uid);
 578                                 if (! *buf)
 579                                         len+=printf("%d", header.uid);
 580                                 else
 581                                         len+=printf("%s", buf);
 582                                 memset(buf, 0, 8*sizeof(char));
 583                                 my_getgrgid(buf, header.gid);
 584                                 if (! *buf)
 585                                         len+=printf("/%-d ", header.gid);
 586                                 else
 587                                         len+=printf("/%-s ", buf);
 588
 589                                 if (header.type==CHRTYPE || header.type==BLKTYPE) {
 590                                         len1=snprintf(buf, sizeof(buf), "%ld,%-ld ",
 591                                                         header.devmajor, header.devminor);
 592                                 } else {
 593                                         len1=snprintf(buf, sizeof(buf), "%lu ", (long)header.size);
 594                                 }
 595                                 /* Jump through some hoops to make the columns match up */
 596                                 for(;(len+len1)<31;len++)
 597                                         printf(" ");
 598                                 printf(buf);
 599
 600                                 /* Use ISO 8610 time format */
 601                                 if (tm) {
 602                                         printf ("%04d-%02d-%02d %02d:%02d:%02d ",
 603                                                         tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
 604                                                         tm->tm_hour, tm->tm_min, tm->tm_sec);
 605                                 }
 606                         }
 607                         printf("%s", header.name);
 608                         if (verboseFlag == TRUE) {
 609                                 if (header.type==LNKTYPE)       /* If this is a link, say so */
 610                                         printf(" link to %s", header.linkname);
 611                                 else if (header.type==SYMTYPE)
 612                                         printf(" -> %s", header.linkname);
 613                         }
 614                         printf("\n");
 615                 }
 616
 617                 /* List contents if we are supposed to do that */
 618                 if (verboseFlag == TRUE && extractFlag == TRUE) {
 619                         /* Now the normal listing */
 620                         FILE *vbFd = stdout;
 621                         if (tostdoutFlag == TRUE)       // If the archive goes to stdout, verbose to stderr
 622                                 vbFd = stderr;
 623                         fprintf(vbFd, "%s\n", header.name);
 624                 }
 625
 626                 /* Remove files if we would overwrite them */
 627                 if (extractFlag == TRUE && tostdoutFlag == FALSE)
 628                         unlink(header.name);
 629
 630                 /* If we got here, we can be certain we have a legitimate
 631                  * header to work with.  So work with it.  */
 632                 switch ( header.type ) {
 633                         case REGTYPE:
 634                         case REGTYPE0:
 635                                 /* If the name ends in a '/' then assume it is
 636                                  * supposed to be a directory, and fall through */
 637                                 if (header.name[strlen(header.name)-1] != '/') {
 638                                         if (tarExtractRegularFile(&header, extractFlag, tostdoutFlag)==FALSE)
 639                                                 errorFlag=TRUE;
 640                                         break;
 641                                 }
 642                         case DIRTYPE:
 643                                 if (tarExtractDirectory( &header, extractFlag, tostdoutFlag)==FALSE)
 644                                         errorFlag=TRUE;
 645                                 break;
 646                         case LNKTYPE:
 647                                 if (tarExtractHardLink( &header, extractFlag, tostdoutFlag)==FALSE)
 648                                         errorFlag=TRUE;
 649                                 break;
 650                         case SYMTYPE:
 651                                 if (tarExtractSymLink( &header, extractFlag, tostdoutFlag)==FALSE)
 652                                         errorFlag=TRUE;
 653                                 break;
 654                         case CHRTYPE:
 655                         case BLKTYPE:
 656                         case FIFOTYPE:
 657                                 if (tarExtractSpecial( &header, extractFlag, tostdoutFlag)==FALSE)
 658                                         errorFlag=TRUE;
 659                                 break;
 660                         default:
 661                                 close( tarFd);
 662                                 return( FALSE);
 663                 }
 664         }
 665         close(tarFd);
 666         if (status > 0) {
 667                 /* Bummer - we read a partial header */
 668                 errorMsg( "Error reading '%s': %s\n", tarName, strerror(errno));
 669                 return ( FALSE);
 670         }
 671         else if (errorFlag==TRUE) {
 672                 errorMsg( "Error exit delayed from previous errors\n");
 673                 return( FALSE);
 674         } else
 675                 return( status);
 676
 677         /* Stuff to do when we are done */
 678 endgame:
 679         close( tarFd);
 680         if ( *(header.name) == '\0' ) {
 681                 if (errorFlag==TRUE)
 682                         errorMsg( "Error exit delayed from previous errors\n");
 683                 else
 684                         return( TRUE);
 685         }
 686         return( FALSE);
 687 }
 688
 689
 690 #ifdef BB_FEATURE_TAR_CREATE
 691
 692 /* Some info to be carried along when creating a new tarball */
 693 struct TarBallInfo
 694 {
 695         char* fileName;               /* File name of the tarball */
 696         int tarFd;                    /* Open-for-write file descriptor
 697                                                                          for the tarball */
 698         struct stat statBuf;          /* Stat info for the tarball, letting
 699                                                                          us know the inode and device that the
 700                                                                          tarball lives, so we can avoid trying
 701                                                                          to include the tarball into itself */
 702         int verboseFlag;              /* Whether to print extra stuff or not */
 703         char** excludeList;           /* List of files to not include */
 704 };
 705 typedef struct TarBallInfo TarBallInfo;
 706
 707
 708 /* Put an octal string into the specified buffer.
 709  * The number is zero and space padded and possibly null padded.
 710  * Returns TRUE if successful.  */
 711 static int putOctal (char *cp, int len, long value)
 712 {
 713         int tempLength;
 714         char tempBuffer[32];
 715         char *tempString = tempBuffer;
 716
 717         /* Create a string of the specified length with an initial space,
 718          * leading zeroes and the octal number, and a trailing null.  */
 719         sprintf (tempString, "%0*lo", len - 1, value);
 720
 721         /* If the string is too large, suppress the leading space.  */
 722         tempLength = strlen (tempString) + 1;
 723         if (tempLength > len) {
 724                 tempLength--;
 725                 tempString++;
 726         }
 727
 728         /* If the string is still too large, suppress the trailing null.  */
 729         if (tempLength > len)
 730                 tempLength--;
 731
 732         /* If the string is still too large, fail.  */
 733         if (tempLength > len)
 734                 return FALSE;
 735
 736         /* Copy the string to the field.  */
 737         memcpy (cp, tempString, len);
 738
 739         return TRUE;
 740 }
 741
 742 /* Write out a tar header for the specified file/directory/whatever */
 743 static int
 744 writeTarHeader(struct TarBallInfo *tbInfo, const char *fileName, struct stat *statbuf)
 745 {
 746         long chksum=0;
 747         struct TarHeader header;
 748 #if defined BB_FEATURE_TAR_EXCLUDE
 749         char** tmpList;
 750 #endif
 751         const unsigned char *cp = (const unsigned char *) &header;
 752         ssize_t size = sizeof(struct TarHeader);
 753
 754         memset( &header, 0, size);
 755
 756         if (*fileName=='/') {
 757                 static int alreadyWarned=FALSE;
 758                 if (alreadyWarned==FALSE) {
 759                         errorMsg("Removing leading '/' from member names\n");
 760                         alreadyWarned=TRUE;
 761                 }
 762                 strncpy(header.name, fileName+1, sizeof(header.name));
 763         }
 764         else {
 765                 strncpy(header.name, fileName, sizeof(header.name));
 766         }
 767
 768 #if defined BB_FEATURE_TAR_EXCLUDE
 769         /* Check for excluded files....  */
 770         for (tmpList=tbInfo->excludeList; tmpList && *tmpList; tmpList++) {
 771                 /* Do some extra hoop jumping for when directory names
 772                  * end in '/' but the entry in tmpList doesn't */
 773                 if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
 774                                         header.name[strlen(header.name)-1]=='/'
 775                                         && strncmp( *tmpList, header.name,
 776                                                 MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
 777                         /* Set the mode to something that is not a regular file, thereby
 778                          * faking out writeTarFile into thinking that nothing further need
 779                          * be done for this file.  Yes, I know this is ugly, but it works. */
 780                         statbuf->st_mode = 0;
 781                         return( TRUE);
 782                 }
 783         }
 784 #endif
 785
 786         putOctal(header.mode, sizeof(header.mode), statbuf->st_mode);
 787         putOctal(header.uid, sizeof(header.uid), statbuf->st_uid);
 788         putOctal(header.gid, sizeof(header.gid), statbuf->st_gid);
 789         putOctal(header.size, sizeof(header.size), 0); /* Regular file size is handled later */
 790         putOctal(header.mtime, sizeof(header.mtime), statbuf->st_mtime);
 791         strncpy(header.magic, TAR_MAGIC TAR_VERSION,
 792                         TAR_MAGIC_LEN + TAR_VERSION_LEN );
 793
 794         /* Enter the user and group names (default to root if it fails) */
 795         my_getpwuid(header.uname, statbuf->st_uid);
 796         if (! *header.uname)
 797                 strcpy(header.uname, "root");
 798         my_getgrgid(header.gname, statbuf->st_gid);
 799         if (! *header.uname)
 800                 strcpy(header.uname, "root");
 801
 802         /* WARNING/NOTICE: I break Hard Links */
 803         if (S_ISLNK(statbuf->st_mode)) {
 804                 int link_size=0;
 805                 char buffer[BUFSIZ];
 806                 header.typeflag  = SYMTYPE;
 807                 link_size = readlink(fileName, buffer, sizeof(buffer) - 1);
 808                 if ( link_size < 0) {
 809                         errorMsg("Error reading symlink '%s': %s\n", header.name, strerror(errno));
 810                         return ( FALSE);
 811                 }
 812                 buffer[link_size] = '\0';
 813                 strncpy(header.linkname, buffer, sizeof(header.linkname));
 814         } else if (S_ISDIR(statbuf->st_mode)) {
 815                 header.typeflag  = DIRTYPE;
 816                 strncat(header.name, "/", sizeof(header.name));
 817         } else if (S_ISCHR(statbuf->st_mode)) {
 818                 header.typeflag  = CHRTYPE;
 819                 putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev));
 820                 putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev));
 821         } else if (S_ISBLK(statbuf->st_mode)) {
 822                 header.typeflag  = BLKTYPE;
 823                 putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev));
 824                 putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev));
 825         } else if (S_ISFIFO(statbuf->st_mode)) {
 826                 header.typeflag  = FIFOTYPE;
 827         } else if (S_ISREG(statbuf->st_mode)) {
 828                 header.typeflag  = REGTYPE;
 829                 putOctal(header.size, sizeof(header.size), statbuf->st_size);
 830         } else {
 831                 errorMsg("%s: Unknown file type\n", fileName);
 832                 return ( FALSE);
 833         }
 834
 835         /* Calculate and store the checksum (i.e. the sum of all of the bytes of
 836          * the header).  The checksum field must be filled with blanks for the
 837          * calculation.  The checksum field is formatted differently from the
 838          * other fields: it has [6] digits, a null, then a space -- rather than
 839          * digits, followed by a null like the other fields... */
 840         memset(header.chksum, ' ', sizeof(header.chksum));
 841         cp = (const unsigned char *) &header;
 842         while (size-- > 0)
 843                 chksum += *cp++;
 844         putOctal(header.chksum, 7, chksum);
 845
 846         /* Now write the header out to disk */
 847         if ((size=fullWrite(tbInfo->tarFd, (char*)&header, sizeof(struct TarHeader))) < 0) {
 848                 errorMsg(io_error, fileName, strerror(errno));
 849                 return ( FALSE);
 850         }
 851         /* Pad the header up to the tar block size */
 852         for (; size<TAR_BLOCK_SIZE; size++) {
 853                 write(tbInfo->tarFd, "\0", 1);
 854         }
 855         /* Now do the verbose thing (or not) */
 856         if (tbInfo->verboseFlag==TRUE) {
 857                 FILE *vbFd = stdout;
 858                 if (tbInfo->tarFd == fileno(stdout))    // If the archive goes to stdout, verbose to stderr
 859                         vbFd = stderr;
 860                 fprintf(vbFd, "%s\n", header.name);
 861         }
 862
 863         return ( TRUE);
 864 }
 865
 866
 867 static int writeFileToTarball(const char *fileName, struct stat *statbuf, void* userData)
 868 {
 869         struct TarBallInfo *tbInfo = (struct TarBallInfo *)userData;
 870
 871         /* It is against the rules to archive a socket */
 872         if (S_ISSOCK(statbuf->st_mode)) {
 873                 errorMsg("%s: socket ignored\n", fileName);
 874                 return( TRUE);
 875         }
 876
 877         /* It is a bad idea to store the archive we are in the process of creating,
 878          * so check the device and inode to be sure that this particular file isn't
 879          * the new tarball */
 880         if (tbInfo->statBuf.st_dev == statbuf->st_dev &&
 881                         tbInfo->statBuf.st_ino == statbuf->st_ino) {
 882                 errorMsg("%s: file is the archive; skipping\n", fileName);
 883                 return( TRUE);
 884         }
 885
 886         if (writeTarHeader(tbInfo, fileName, statbuf)==FALSE) {
 887                 return( FALSE);
 888         }
 889
 890         /* Now, if the file is a regular file, copy it out to the tarball */
 891         if (S_ISREG(statbuf->st_mode)) {
 892                 int  inputFileFd;
 893                 char buffer[BUFSIZ];
 894                 ssize_t size=0, readSize=0;
 895
 896                 /* open the file we want to archive, and make sure all is well */
 897                 if ((inputFileFd = open(fileName, O_RDONLY)) < 0) {
 898                         errorMsg("%s: Cannot open: %s\n", fileName, strerror(errno));
 899                         return( FALSE);
 900                 }
 901
 902                 /* write the file to the archive */
 903                 while ( (size = fullRead(inputFileFd, buffer, sizeof(buffer))) > 0 ) {
 904                         if (fullWrite(tbInfo->tarFd, buffer, size) != size ) {
 905                                 /* Output file seems to have a problem */
 906                                 errorMsg(io_error, fileName, strerror(errno));
 907                                 return( FALSE);
 908                         }
 909                         readSize+=size;
 910                 }
 911                 if (size == -1) {
 912                         errorMsg(io_error, fileName, strerror(errno));
 913                         return( FALSE);
 914                 }
 915                 /* Pad the file up to the tar block size */
 916                 for (; (readSize%TAR_BLOCK_SIZE) != 0; readSize++) {
 917                         write(tbInfo->tarFd, "\0", 1);
 918                 }
 919                 close( inputFileFd);
 920         }
 921
 922         return( TRUE);
 923 }
 924
 925 static int writeTarFile(const char* tarName, int tostdoutFlag,
 926                 int verboseFlag, int argc, char **argv, char** excludeList)
 927 {
 928         int tarFd=-1;
 929         int errorFlag=FALSE;
 930         ssize_t size;
 931         struct TarBallInfo tbInfo;
 932         tbInfo.verboseFlag = verboseFlag;
 933
 934         /* Make sure there is at least one file to tar up.  */
 935         if (argc <= 0)
 936                 fatalError("Cowardly refusing to create an empty archive\n");
 937
 938         /* Open the tar file for writing.  */
 939         if (tostdoutFlag == TRUE)
 940                 tbInfo.tarFd = fileno(stdout);
 941         else
 942                 tbInfo.tarFd = open (tarName, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 943         if (tbInfo.tarFd < 0) {
 944                 errorMsg( "Error opening '%s': %s\n", tarName, strerror(errno));
 945                 return ( FALSE);
 946         }
 947         tbInfo.excludeList=excludeList;
 948         /* Store the stat info for the tarball's file, so
 949          * can avoid including the tarball into itself....  */
 950         if (fstat(tbInfo.tarFd, &tbInfo.statBuf) < 0)
 951                 fatalError(io_error, tarName, strerror(errno));
 952
 953         /* Set the umask for this process so it doesn't
 954          * screw up permission setting for us later. */
 955         umask(0);
 956
 957         /* Read the directory/files and iterate over them one at a time */
 958         while (argc-- > 0) {
 959                 if (recursiveAction(*argv++, TRUE, FALSE, FALSE,
 960                                         writeFileToTarball, writeFileToTarball,
 961                                         (void*) &tbInfo) == FALSE) {
 962                         errorFlag = TRUE;
 963                 }
 964         }
 965         /* Write two empty blocks to the end of the archive */
 966         for (size=0; size<(2*TAR_BLOCK_SIZE); size++) {
 967                 write(tbInfo.tarFd, "\0", 1);
 968         }
 969
 970         /* To be pedantically correct, we would check if the tarball
 971          * is smaller then 20 tar blocks, and pad it if it was smaller,
 972          * but that isn't necessary for GNU tar interoperability, and
 973          * so is considered a waste of space */
 974
 975         /* Hang up the tools, close up shop, head home */
 976         close(tarFd);
 977         if (errorFlag == TRUE) {
 978                 errorMsg("Error exit delayed from previous errors\n");
 979                 return(FALSE);
 980         }
 981         return( TRUE);
 982 }
 983
 984
 985 #endif
 986