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 "busybox.h"
  40 #define BB_DECLARE_EXTERN
  41 #define bb_need_io_error
  42 #define bb_need_name_longer_than_foo
  43 #include "messages.c"
  44 #include <stdio.h>
  45 #include <dirent.h>
  46 #include <errno.h>
  47 #include <fcntl.h>
  48 #include <signal.h>
  49 #include <time.h>
  50 #include <utime.h>
  51 #include <sys/types.h>
  52 #include <sys/sysmacros.h>
  53 #include <getopt.h>
  54
  55 /* Tar file constants  */
  56 #ifndef MAJOR
  57 #define MAJOR(dev) (((dev)>>8)&0xff)
  58 #define MINOR(dev) ((dev)&0xff)
  59 #endif
  60
  61 #define NAME_SIZE       100
  62
  63 /* POSIX tar Header Block, from POSIX 1003.1-1990  */
  64 struct TarHeader
  65 {
  66                                 /* byte offset */
  67         char name[NAME_SIZE];         /*   0-99 */
  68         char mode[8];                 /* 100-107 */
  69         char uid[8];                  /* 108-115 */
  70         char gid[8];                  /* 116-123 */
  71         char size[12];                /* 124-135 */
  72         char mtime[12];               /* 136-147 */
  73         char chksum[8];               /* 148-155 */
  74         char typeflag;                /* 156-156 */
  75         char linkname[NAME_SIZE];     /* 157-256 */
  76         char magic[6];                /* 257-262 */
  77         char version[2];              /* 263-264 */
  78         char uname[32];               /* 265-296 */
  79         char gname[32];               /* 297-328 */
  80         char devmajor[8];             /* 329-336 */
  81         char devminor[8];             /* 337-344 */
  82         char prefix[155];             /* 345-499 */
  83         char padding[12];             /* 500-512 (pad to exactly the TAR_BLOCK_SIZE) */
  84 };
  85 typedef struct TarHeader TarHeader;
  86
  87
  88 /* A few useful constants */
  89 #define TAR_MAGIC          "ustar"        /* ustar and a null */
  90 #define TAR_VERSION        "  "           /* Be compatable with GNU tar format */
  91 #define TAR_MAGIC_LEN       6
  92 #define TAR_VERSION_LEN     2
  93 #define TAR_BLOCK_SIZE      512
  94
  95 /* A nice enum with all the possible tar file content types */
  96 enum TarFileType
  97 {
  98         REGTYPE  = '0',            /* regular file */
  99         REGTYPE0 = '\0',           /* regular file (ancient bug compat)*/
 100         LNKTYPE  = '1',            /* hard link */
 101         SYMTYPE  = '2',            /* symbolic link */
 102         CHRTYPE  = '3',            /* character special */
 103         BLKTYPE  = '4',            /* block special */
 104         DIRTYPE  = '5',            /* directory */
 105         FIFOTYPE = '6',            /* FIFO special */
 106         CONTTYPE = '7',            /* reserved */
 107         GNULONGLINK = 'K',         /* GNU long (>100 chars) link name */
 108         GNULONGNAME = 'L',         /* GNU long (>100 chars) file name */
 109 };
 110 typedef enum TarFileType TarFileType;
 111
 112 /* This struct ignores magic, non-numeric user name,
 113  * non-numeric group name, and the checksum, since
 114  * these are all ignored by BusyBox tar. */
 115 struct TarInfo
 116 {
 117         int              tarFd;          /* An open file descriptor for reading from the tarball */
 118         char *           name;           /* File name */
 119         mode_t           mode;           /* Unix mode, including device bits. */
 120         uid_t            uid;            /* Numeric UID */
 121         gid_t            gid;            /* Numeric GID */
 122         size_t           size;           /* Size of file */
 123         time_t           mtime;          /* Last-modified time */
 124         enum TarFileType type;           /* Regular, directory, link, etc */
 125         char *           linkname;       /* Name for symbolic and hard links */
 126         long             devmajor;       /* Major number for special device */
 127         long             devminor;       /* Minor number for special device */
 128 };
 129 typedef struct TarInfo TarInfo;
 130
 131 /* Local procedures to restore files from a tar file.  */
 132 static int readTarFile(const char* tarName, int extractFlag, int listFlag,
 133                 int tostdoutFlag, int verboseFlag, char** extractList,
 134                 char** excludeList);
 135
 136
 137
 138 #ifdef BB_FEATURE_TAR_CREATE
 139 /* Local procedures to save files into a tar file.  */
 140 static int writeTarFile(const char* tarName, int verboseFlag, char **argv,
 141                 char** excludeList);
 142 #endif
 143
 144 extern int tar_main(int argc, char **argv)
 145 {
 146         char** excludeList=NULL;
 147 #if defined BB_FEATURE_TAR_EXCLUDE
 148         int excludeListSize=0;
 149 #endif
 150         const char *tarName="-";
 151         int listFlag     = FALSE;
 152         int extractFlag  = FALSE;
 153         int createFlag   = FALSE;
 154         int verboseFlag  = FALSE;
 155         int tostdoutFlag = FALSE;
 156         int firstOpt = TRUE;
 157         int stopIt;
 158
 159
 160         if (argc <= 1)
 161                 usage(tar_usage);
 162
 163         while (*(++argv) && (**argv == '-' || firstOpt == TRUE)) {
 164                 firstOpt=FALSE;
 165                 stopIt=FALSE;
 166                 while (stopIt==FALSE && **argv) {
 167                         switch (*((*argv)++)) {
 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                                         break;
 189                                 case 'f':
 190                                         if (*tarName != '-')
 191                                                 fatalError( "Only one 'f' option allowed\n");
 192                                         tarName = *(++argv);
 193                                         if (tarName == NULL)
 194                                                 fatalError( "Option requires an argument: No file specified\n");
 195                                         stopIt=TRUE;
 196                                         break;
 197 #if defined BB_FEATURE_TAR_EXCLUDE
 198                                 case 'e':
 199                                         if (strcmp(*argv, "exclude")==0) {
 200                                                 excludeList=xrealloc( excludeList, sizeof(char**) * (excludeListSize+2));
 201                                                 excludeList[excludeListSize] = *(++argv);
 202                                                 if (excludeList[excludeListSize] == NULL)
 203                                                         fatalError( "Option requires an argument: No file specified\n");
 204                                                 /* Remove leading "/"s */
 205                                                 if (*excludeList[excludeListSize] =='/')
 206                                                         excludeList[excludeListSize] = (excludeList[excludeListSize])+1;
 207                                                 /* Tack a NULL onto the end of the list */
 208                                                 excludeList[++excludeListSize] = NULL;
 209                                                 stopIt=TRUE;
 210                                                 break;
 211                                         }
 212 #endif
 213                                 case '-':
 214                                                 break;
 215                                 default:
 216                                         usage(tar_usage);
 217                         }
 218                 }
 219         }
 220
 221         /*
 222          * Do the correct type of action supplying the rest of the
 223          * command line arguments as the list of files to process.
 224          */
 225         if (createFlag == TRUE) {
 226 #ifndef BB_FEATURE_TAR_CREATE
 227                 fatalError( "This version of tar was not compiled with tar creation support.\n");
 228 #else
 229                 exit(writeTarFile(tarName, verboseFlag, argv, excludeList));
 230 #endif
 231         }
 232         if (listFlag == TRUE || extractFlag == TRUE) {
 233                 exit(readTarFile(tarName, extractFlag, listFlag, tostdoutFlag,
 234                                         verboseFlag, argv, excludeList));
 235         }
 236
 237   flagError:
 238         fatalError( "Exactly one of 'c', 'x' or 't' must be specified\n");
 239 }
 240
 241 static void
 242 fixUpPermissions(TarInfo *header)
 243 {
 244         struct utimbuf t;
 245         /* Now set permissions etc for the new file */
 246         chown(header->name, header->uid, header->gid);
 247         chmod(header->name, header->mode);
 248         /* Reset the time */
 249         t.actime = time(0);
 250         t.modtime = header->mtime;
 251         utime(header->name, &t);
 252 }
 253
 254 static int
 255 tarExtractRegularFile(TarInfo *header, int extractFlag, int tostdoutFlag)
 256 {
 257         size_t  writeSize;
 258         size_t  readSize;
 259         size_t  actualWriteSz;
 260         char    buffer[BUFSIZ];
 261         size_t  size = header->size;
 262         int outFd=fileno(stdout);
 263
 264         /* Open the file to be written, if a file is supposed to be written */
 265         if (extractFlag==TRUE && tostdoutFlag==FALSE) {
 266                 /* Create the path to the file, just in case it isn't there...
 267                  * This should not screw up path permissions or anything. */
 268                 createPath(header->name, 0777);
 269                 if ((outFd=open(header->name, O_CREAT|O_TRUNC|O_WRONLY,
 270                                                 header->mode & ~S_IFMT)) < 0) {
 271                         errorMsg(io_error, header->name, strerror(errno));
 272                         return( FALSE);
 273                 }
 274         }
 275
 276         /* Write out the file, if we are supposed to be doing that */
 277         while ( size > 0 ) {
 278                 actualWriteSz=0;
 279                 if ( size > sizeof(buffer) )
 280                         writeSize = readSize = sizeof(buffer);
 281                 else {
 282                         int mod = size % 512;
 283                         if ( mod != 0 )
 284                                 readSize = size + (512 - mod);
 285                         else
 286                                 readSize = size;
 287                         writeSize = size;
 288                 }
 289                 if ( (readSize = fullRead(header->tarFd, buffer, readSize)) <= 0 ) {
 290                         /* Tarball seems to have a problem */
 291                         errorMsg("Unexpected EOF in archive\n");
 292                         return( FALSE);
 293                 }
 294                 if ( readSize < writeSize )
 295                         writeSize = readSize;
 296
 297                 /* Write out the file, if we are supposed to be doing that */
 298                 if (extractFlag==TRUE) {
 299
 300                         if ((actualWriteSz=fullWrite(outFd, buffer, writeSize)) != writeSize ) {
 301                                 /* Output file seems to have a problem */
 302                                 errorMsg(io_error, header->name, strerror(errno));
 303                                 return( FALSE);
 304                         }
 305                 } else {
 306                         actualWriteSz=writeSize;
 307                 }
 308
 309                 size -= actualWriteSz;
 310         }
 311
 312         /* Now we are done writing the file out, so try
 313          * and fix up the permissions and whatnot */
 314         if (extractFlag==TRUE && tostdoutFlag==FALSE) {
 315                 close(outFd);
 316                 fixUpPermissions(header);
 317         }
 318         return( TRUE);
 319 }
 320
 321 static int
 322 tarExtractDirectory(TarInfo *header, int extractFlag, int tostdoutFlag)
 323 {
 324
 325         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 326                 return( TRUE);
 327
 328         if (createPath(header->name, header->mode) != TRUE) {
 329                 errorMsg("%s: Cannot mkdir: %s\n",
 330                                 header->name, strerror(errno));
 331                 return( FALSE);
 332         }
 333         /* make the final component, just in case it was
 334          * omitted by createPath() (which will skip the
 335          * directory if it doesn't have a terminating '/') */
 336         if (mkdir(header->name, header->mode) == 0) {
 337                 fixUpPermissions(header);
 338         }
 339         return( TRUE);
 340 }
 341
 342 static int
 343 tarExtractHardLink(TarInfo *header, int extractFlag, int tostdoutFlag)
 344 {
 345         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 346                 return( TRUE);
 347
 348         if (link(header->linkname, header->name) < 0) {
 349                 errorMsg("%s: Cannot create hard link to '%s': %s\n",
 350                                 header->name, header->linkname, strerror(errno));
 351                 return( FALSE);
 352         }
 353
 354         /* Now set permissions etc for the new directory */
 355         fixUpPermissions(header);
 356         return( TRUE);
 357 }
 358
 359 static int
 360 tarExtractSymLink(TarInfo *header, int extractFlag, int tostdoutFlag)
 361 {
 362         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 363                 return( TRUE);
 364
 365 #ifdef  S_ISLNK
 366         if (symlink(header->linkname, header->name) < 0) {
 367                 errorMsg("%s: Cannot create symlink to '%s': %s\n",
 368                                 header->name, header->linkname, strerror(errno));
 369                 return( FALSE);
 370         }
 371         /* Try to change ownership of the symlink.
 372          * If libs doesn't support that, don't bother.
 373          * Changing the pointed-to-file is the Wrong Thing(tm).
 374          */
 375 #if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
 376         lchown(header->name, header->uid, header->gid);
 377 #endif
 378
 379         /* Do not change permissions or date on symlink,
 380          * since it changes the pointed to file instead.  duh. */
 381 #else
 382         errorMsg("%s: Cannot create symlink to '%s': %s\n",
 383                         header->name, header->linkname,
 384                         "symlinks not supported");
 385 #endif
 386         return( TRUE);
 387 }
 388
 389 static int
 390 tarExtractSpecial(TarInfo *header, int extractFlag, int tostdoutFlag)
 391 {
 392         if (extractFlag==FALSE || tostdoutFlag==TRUE)
 393                 return( TRUE);
 394
 395         if (S_ISCHR(header->mode) || S_ISBLK(header->mode) || S_ISSOCK(header->mode)) {
 396                 if (mknod(header->name, header->mode, makedev(header->devmajor, header->devminor)) < 0) {
 397                         errorMsg("%s: Cannot mknod: %s\n",
 398                                 header->name, strerror(errno));
 399                         return( FALSE);
 400                 }
 401         } else if (S_ISFIFO(header->mode)) {
 402                 if (mkfifo(header->name, header->mode) < 0) {
 403                         errorMsg("%s: Cannot mkfifo: %s\n",
 404                                 header->name, strerror(errno));
 405                         return( FALSE);
 406                 }
 407         }
 408
 409         /* Now set permissions etc for the new directory */
 410         fixUpPermissions(header);
 411         return( TRUE);
 412 }
 413
 414 /* Read an octal value in a field of the specified width, with optional
 415  * spaces on both sides of the number and with an optional null character
 416  * at the end.  Returns -1 on an illegal format.  */
 417 static long getOctal(const char *cp, int size)
 418 {
 419         long val = 0;
 420
 421         for(;(size > 0) && (*cp == ' '); cp++, size--);
 422         if ((size == 0) || !isOctal(*cp))
 423                 return -1;
 424         for(; (size > 0) && isOctal(*cp); size--) {
 425                 val = val * 8 + *cp++ - '0';
 426         }
 427         for (;(size > 0) && (*cp == ' '); cp++, size--);
 428         if ((size > 0) && *cp)
 429                 return -1;
 430         return val;
 431 }
 432
 433
 434 /* Parse the tar header and fill in the nice struct with the details */
 435 static int
 436 readTarHeader(struct TarHeader *rawHeader, struct TarInfo *header)
 437 {
 438         int i;
 439         long chksum, sum=0;
 440         unsigned char *s = (unsigned char *)rawHeader;
 441
 442         header->name  = rawHeader->name;
 443         /* Check for and relativify any absolute paths */
 444         if ( *(header->name) == '/' ) {
 445                 static int alreadyWarned=FALSE;
 446
 447                 while (*(header->name) == '/')
 448                         ++*(header->name);
 449
 450                 if (alreadyWarned == FALSE) {
 451                         errorMsg("Removing leading '/' from member names\n");
 452                         alreadyWarned = TRUE;
 453                 }
 454         }
 455
 456         header->mode  = getOctal(rawHeader->mode, sizeof(rawHeader->mode));
 457         header->uid   =  getOctal(rawHeader->uid, sizeof(rawHeader->uid));
 458         header->gid   =  getOctal(rawHeader->gid, sizeof(rawHeader->gid));
 459         header->size  = getOctal(rawHeader->size, sizeof(rawHeader->size));
 460         header->mtime = getOctal(rawHeader->mtime, sizeof(rawHeader->mtime));
 461         chksum = getOctal(rawHeader->chksum, sizeof(rawHeader->chksum));
 462         header->type  = rawHeader->typeflag;
 463         header->linkname  = rawHeader->linkname;
 464         header->devmajor  = getOctal(rawHeader->devmajor, sizeof(rawHeader->devmajor));
 465         header->devminor  = getOctal(rawHeader->devminor, sizeof(rawHeader->devminor));
 466
 467         /* Check the checksum */
 468         for (i = sizeof(*rawHeader); i-- != 0;) {
 469                 sum += *s++;
 470         }
 471         /* Remove the effects of the checksum field (replace
 472          * with blanks for the purposes of the checksum) */
 473         s = rawHeader->chksum;
 474         for (i = sizeof(rawHeader->chksum) ; i-- != 0;) {
 475                 sum -= *s++;
 476         }
 477         sum += ' ' * sizeof(rawHeader->chksum);
 478         if (sum == chksum )
 479                 return ( TRUE);
 480         return( FALSE);
 481 }
 482
 483
 484 /*
 485  * Read a tar file and extract or list the specified files within it.
 486  * If the list is empty than all files are extracted or listed.
 487  */
 488 static int readTarFile(const char* tarName, int extractFlag, int listFlag,
 489                 int tostdoutFlag, int verboseFlag, char** extractList,
 490                 char** excludeList)
 491 {
 492         int status, tarFd=-1;
 493         int errorFlag=FALSE;
 494         int skipNextHeaderFlag=FALSE;
 495         TarHeader rawHeader;
 496         TarInfo header;
 497         char** tmpList;
 498
 499         /* Open the tar file for reading.  */
 500         if (!strcmp(tarName, "-"))
 501                 tarFd = fileno(stdin);
 502         else
 503                 tarFd = open(tarName, O_RDONLY);
 504         if (tarFd < 0) {
 505                 errorMsg( "Error opening '%s': %s\n", tarName, strerror(errno));
 506                 return ( FALSE);
 507         }
 508
 509         /* Set the umask for this process so it doesn't
 510          * screw up permission setting for us later. */
 511         umask(0);
 512
 513         /* Read the tar file, and iterate over it one file at a time */
 514         while ( (status = fullRead(tarFd, (char*)&rawHeader, TAR_BLOCK_SIZE)) == TAR_BLOCK_SIZE ) {
 515
 516                 /* Try to read the header */
 517                 if ( readTarHeader(&rawHeader, &header) == FALSE ) {
 518                         if ( *(header.name) == '\0' ) {
 519                                 goto endgame;
 520                         } else {
 521                                 errorFlag=TRUE;
 522                                 errorMsg("Bad tar header, skipping\n");
 523                                 continue;
 524                         }
 525                 }
 526                 if ( *(header.name) == '\0' )
 527                                 goto endgame;
 528                 header.tarFd = tarFd;
 529
 530                 /* Skip funky extra GNU headers that precede long files */
 531                 if ( (header.type == GNULONGNAME) || (header.type == GNULONGLINK) ) {
 532                         skipNextHeaderFlag=TRUE;
 533                         if (tarExtractRegularFile(&header, FALSE, FALSE) == FALSE)
 534                                 errorFlag = TRUE;
 535                         continue;
 536                 }
 537                 if ( skipNextHeaderFlag == TRUE ) {
 538                         skipNextHeaderFlag=FALSE;
 539                         errorMsg(name_longer_than_foo, NAME_SIZE);
 540                         if (tarExtractRegularFile(&header, FALSE, FALSE) == FALSE)
 541                                 errorFlag = TRUE;
 542                         continue;
 543                 }
 544
 545 #if defined BB_FEATURE_TAR_EXCLUDE
 546                 {
 547                         int skipFlag=FALSE;
 548                         /* Check for excluded files....  */
 549                         for (tmpList=excludeList; tmpList && *tmpList; tmpList++) {
 550                                 /* Do some extra hoop jumping for when directory names
 551                                  * end in '/' but the entry in tmpList doesn't */
 552                                 if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
 553                                                         header.name[strlen(header.name)-1]=='/'
 554                                                         && strncmp( *tmpList, header.name,
 555                                                                 MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
 556                                         /* If it is a regular file, pretend to extract it with
 557                                          * the extractFlag set to FALSE, so the junk in the tarball
 558                                          * is properly skipped over */
 559                                         if ( header.type==REGTYPE || header.type==REGTYPE0 ) {
 560                                                 if (tarExtractRegularFile(&header, FALSE, FALSE) == FALSE)
 561                                                         errorFlag = TRUE;
 562                                         }
 563                                         skipFlag=TRUE;
 564                                         break;
 565                                 }
 566                         }
 567                         /* There are not the droids you're looking for, move along */
 568                         if (skipFlag==TRUE)
 569                                 continue;
 570                 }
 571 #endif
 572                 if (*extractList != NULL) {
 573                         int skipFlag = TRUE;
 574                         for (tmpList = extractList; *tmpList != NULL; tmpList++) {
 575                                 if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
 576                                                         header.name[strlen(header.name)-1]=='/'
 577                                                         && strncmp( *tmpList, header.name,
 578                                                                 MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
 579                                         /* If it is a regular file, pretend to extract it with
 580                                          * the extractFlag set to FALSE, so the junk in the tarball
 581                                          * is properly skipped over */
 582                                         skipFlag = FALSE;
 583                                         break;
 584                                 }
 585                         }
 586                         /* There are not the droids you're looking for, move along */
 587                         if (skipFlag == TRUE) {
 588                                 if ( header.type==REGTYPE || header.type==REGTYPE0 )
 589                                         if (tarExtractRegularFile(&header, FALSE, FALSE) == FALSE)
 590                                                 errorFlag = TRUE;
 591                                 continue;
 592                         }
 593                 }
 594
 595                 if (listFlag == TRUE) {
 596                         /* Special treatment if the list (-t) flag is on */
 597                         if (verboseFlag == TRUE) {
 598                                 int len, len1;
 599                                 char buf[35];
 600                                 struct tm *tm = localtime (&(header.mtime));
 601
 602                                 len=printf("%s ", modeString(header.mode));
 603                                 memset(buf, 0, 8*sizeof(char));
 604                                 my_getpwuid(buf, header.uid);
 605                                 if (! *buf)
 606                                         len+=printf("%d", header.uid);
 607                                 else
 608                                         len+=printf("%s", buf);
 609                                 memset(buf, 0, 8*sizeof(char));
 610                                 my_getgrgid(buf, header.gid);
 611                                 if (! *buf)
 612                                         len+=printf("/%-d ", header.gid);
 613                                 else
 614                                         len+=printf("/%-s ", buf);
 615
 616                                 if (header.type==CHRTYPE || header.type==BLKTYPE) {
 617                                         len1=snprintf(buf, sizeof(buf), "%ld,%-ld ",
 618                                                         header.devmajor, header.devminor);
 619                                 } else {
 620                                         len1=snprintf(buf, sizeof(buf), "%lu ", (long)header.size);
 621                                 }
 622                                 /* Jump through some hoops to make the columns match up */
 623                                 for(;(len+len1)<31;len++)
 624                                         printf(" ");
 625                                 printf(buf);
 626
 627                                 /* Use ISO 8610 time format */
 628                                 if (tm) {
 629                                         printf ("%04d-%02d-%02d %02d:%02d:%02d ",
 630                                                         tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
 631                                                         tm->tm_hour, tm->tm_min, tm->tm_sec);
 632                                 }
 633                         }
 634                         printf("%s", header.name);
 635                         if (verboseFlag == TRUE) {
 636                                 if (header.type==LNKTYPE)       /* If this is a link, say so */
 637                                         printf(" link to %s", header.linkname);
 638                                 else if (header.type==SYMTYPE)
 639                                         printf(" -> %s", header.linkname);
 640                         }
 641                         printf("\n");
 642                 }
 643
 644                 /* List contents if we are supposed to do that */
 645                 if (verboseFlag == TRUE && extractFlag == TRUE) {
 646                         /* Now the normal listing */
 647                         FILE *vbFd = stdout;
 648                         if (tostdoutFlag == TRUE)       // If the archive goes to stdout, verbose to stderr
 649                                 vbFd = stderr;
 650                         fprintf(vbFd, "%s\n", header.name);
 651                 }
 652
 653                 /* Remove files if we would overwrite them */
 654                 if (extractFlag == TRUE && tostdoutFlag == FALSE)
 655                         unlink(header.name);
 656
 657                 /* If we got here, we can be certain we have a legitimate
 658                  * header to work with.  So work with it.  */
 659                 switch ( header.type ) {
 660                         case REGTYPE:
 661                         case REGTYPE0:
 662                                 /* If the name ends in a '/' then assume it is
 663                                  * supposed to be a directory, and fall through */
 664                                 if (header.name[strlen(header.name)-1] != '/') {
 665                                         if (tarExtractRegularFile(&header, extractFlag, tostdoutFlag)==FALSE)
 666                                                 errorFlag=TRUE;
 667                                         break;
 668                                 }
 669                         case DIRTYPE:
 670                                 if (tarExtractDirectory( &header, extractFlag, tostdoutFlag)==FALSE)
 671                                         errorFlag=TRUE;
 672                                 break;
 673                         case LNKTYPE:
 674                                 if (tarExtractHardLink( &header, extractFlag, tostdoutFlag)==FALSE)
 675                                         errorFlag=TRUE;
 676                                 break;
 677                         case SYMTYPE:
 678                                 if (tarExtractSymLink( &header, extractFlag, tostdoutFlag)==FALSE)
 679                                         errorFlag=TRUE;
 680                                 break;
 681                         case CHRTYPE:
 682                         case BLKTYPE:
 683                         case FIFOTYPE:
 684                                 if (tarExtractSpecial( &header, extractFlag, tostdoutFlag)==FALSE)
 685                                         errorFlag=TRUE;
 686                                 break;
 687 #if 0
 688                         /* Handled earlier */
 689                         case GNULONGNAME:
 690                         case GNULONGLINK:
 691                                 skipNextHeaderFlag=TRUE;
 692                                 break;
 693 #endif
 694                         default:
 695                                 errorMsg("Unknown file type '%c' in tar file\n", header.type);
 696                                 close( tarFd);
 697                                 return( FALSE);
 698                 }
 699         }
 700         close(tarFd);
 701         if (status > 0) {
 702                 /* Bummer - we read a partial header */
 703                 errorMsg( "Error reading '%s': %s\n", tarName, strerror(errno));
 704                 return ( FALSE);
 705         }
 706         else if (errorFlag==TRUE) {
 707                 errorMsg( "Error exit delayed from previous errors\n");
 708                 return( FALSE);
 709         } else
 710                 return( status);
 711
 712         /* Stuff to do when we are done */
 713 endgame:
 714         close( tarFd);
 715         if ( *(header.name) == '\0' ) {
 716                 if (errorFlag==TRUE)
 717                         errorMsg( "Error exit delayed from previous errors\n");
 718                 else
 719                         return( TRUE);
 720         }
 721         return( FALSE);
 722 }
 723
 724
 725 #ifdef BB_FEATURE_TAR_CREATE
 726
 727 /* Some info to be carried along when creating a new tarball */
 728 struct TarBallInfo
 729 {
 730         char* fileName;               /* File name of the tarball */
 731         int tarFd;                    /* Open-for-write file descriptor
 732                                                                          for the tarball */
 733         struct stat statBuf;          /* Stat info for the tarball, letting
 734                                                                          us know the inode and device that the
 735                                                                          tarball lives, so we can avoid trying
 736                                                                          to include the tarball into itself */
 737         int verboseFlag;              /* Whether to print extra stuff or not */
 738         char** excludeList;           /* List of files to not include */
 739 };
 740 typedef struct TarBallInfo TarBallInfo;
 741
 742
 743 /* Put an octal string into the specified buffer.
 744  * The number is zero and space padded and possibly null padded.
 745  * Returns TRUE if successful.  */
 746 static int putOctal (char *cp, int len, long value)
 747 {
 748         int tempLength;
 749         char tempBuffer[32];
 750         char *tempString = tempBuffer;
 751
 752         /* Create a string of the specified length with an initial space,
 753          * leading zeroes and the octal number, and a trailing null.  */
 754         sprintf (tempString, "%0*lo", len - 1, value);
 755
 756         /* If the string is too large, suppress the leading space.  */
 757         tempLength = strlen (tempString) + 1;
 758         if (tempLength > len) {
 759                 tempLength--;
 760                 tempString++;
 761         }
 762
 763         /* If the string is still too large, suppress the trailing null.  */
 764         if (tempLength > len)
 765                 tempLength--;
 766
 767         /* If the string is still too large, fail.  */
 768         if (tempLength > len)
 769                 return FALSE;
 770
 771         /* Copy the string to the field.  */
 772         memcpy (cp, tempString, len);
 773
 774         return TRUE;
 775 }
 776
 777 /* Write out a tar header for the specified file/directory/whatever */
 778 static int
 779 writeTarHeader(struct TarBallInfo *tbInfo, const char *fileName, struct stat *statbuf)
 780 {
 781         long chksum=0;
 782         struct TarHeader header;
 783 #if defined BB_FEATURE_TAR_EXCLUDE
 784         char** tmpList;
 785 #endif
 786         const unsigned char *cp = (const unsigned char *) &header;
 787         ssize_t size = sizeof(struct TarHeader);
 788
 789         memset( &header, 0, size);
 790
 791         if (*fileName=='/') {
 792                 static int alreadyWarned=FALSE;
 793                 if (alreadyWarned==FALSE) {
 794                         errorMsg("Removing leading '/' from member names\n");
 795                         alreadyWarned=TRUE;
 796                 }
 797                 strncpy(header.name, fileName+1, sizeof(header.name));
 798         }
 799         else {
 800                 strncpy(header.name, fileName, sizeof(header.name));
 801         }
 802
 803 #if defined BB_FEATURE_TAR_EXCLUDE
 804         /* Check for excluded files....  */
 805         for (tmpList=tbInfo->excludeList; tmpList && *tmpList; tmpList++) {
 806                 /* Do some extra hoop jumping for when directory names
 807                  * end in '/' but the entry in tmpList doesn't */
 808                 if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
 809                                         header.name[strlen(header.name)-1]=='/'
 810                                         && strncmp( *tmpList, header.name,
 811                                                 MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
 812                         /* Set the mode to something that is not a regular file, thereby
 813                          * faking out writeTarFile into thinking that nothing further need
 814                          * be done for this file.  Yes, I know this is ugly, but it works. */
 815                         statbuf->st_mode = 0;
 816                         return( TRUE);
 817                 }
 818         }
 819 #endif
 820
 821         putOctal(header.mode, sizeof(header.mode), statbuf->st_mode);
 822         putOctal(header.uid, sizeof(header.uid), statbuf->st_uid);
 823         putOctal(header.gid, sizeof(header.gid), statbuf->st_gid);
 824         putOctal(header.size, sizeof(header.size), 0); /* Regular file size is handled later */
 825         putOctal(header.mtime, sizeof(header.mtime), statbuf->st_mtime);
 826         strncpy(header.magic, TAR_MAGIC TAR_VERSION,
 827                         TAR_MAGIC_LEN + TAR_VERSION_LEN );
 828
 829         /* Enter the user and group names (default to root if it fails) */
 830         my_getpwuid(header.uname, statbuf->st_uid);
 831         if (! *header.uname)
 832                 strcpy(header.uname, "root");
 833         my_getgrgid(header.gname, statbuf->st_gid);
 834         if (! *header.uname)
 835                 strcpy(header.uname, "root");
 836
 837         /* WARNING/NOTICE: I break Hard Links */
 838         if (S_ISLNK(statbuf->st_mode)) {
 839                 int link_size=0;
 840                 char buffer[BUFSIZ];
 841                 header.typeflag  = SYMTYPE;
 842                 link_size = readlink(fileName, buffer, sizeof(buffer) - 1);
 843                 if ( link_size < 0) {
 844                         errorMsg("Error reading symlink '%s': %s\n", header.name, strerror(errno));
 845                         return ( FALSE);
 846                 }
 847                 buffer[link_size] = '\0';
 848                 strncpy(header.linkname, buffer, sizeof(header.linkname));
 849         } else if (S_ISDIR(statbuf->st_mode)) {
 850                 header.typeflag  = DIRTYPE;
 851                 strncat(header.name, "/", sizeof(header.name));
 852         } else if (S_ISCHR(statbuf->st_mode)) {
 853                 header.typeflag  = CHRTYPE;
 854                 putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev));
 855                 putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev));
 856         } else if (S_ISBLK(statbuf->st_mode)) {
 857                 header.typeflag  = BLKTYPE;
 858                 putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev));
 859                 putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev));
 860         } else if (S_ISFIFO(statbuf->st_mode)) {
 861                 header.typeflag  = FIFOTYPE;
 862         } else if (S_ISREG(statbuf->st_mode)) {
 863                 header.typeflag  = REGTYPE;
 864                 putOctal(header.size, sizeof(header.size), statbuf->st_size);
 865         } else {
 866                 errorMsg("%s: Unknown file type\n", fileName);
 867                 return ( FALSE);
 868         }
 869
 870         /* Calculate and store the checksum (i.e. the sum of all of the bytes of
 871          * the header).  The checksum field must be filled with blanks for the
 872          * calculation.  The checksum field is formatted differently from the
 873          * other fields: it has [6] digits, a null, then a space -- rather than
 874          * digits, followed by a null like the other fields... */
 875         memset(header.chksum, ' ', sizeof(header.chksum));
 876         cp = (const unsigned char *) &header;
 877         while (size-- > 0)
 878                 chksum += *cp++;
 879         putOctal(header.chksum, 7, chksum);
 880
 881         /* Now write the header out to disk */
 882         if ((size=fullWrite(tbInfo->tarFd, (char*)&header, sizeof(struct TarHeader))) < 0) {
 883                 errorMsg(io_error, fileName, strerror(errno));
 884                 return ( FALSE);
 885         }
 886         /* Pad the header up to the tar block size */
 887         for (; size<TAR_BLOCK_SIZE; size++) {
 888                 write(tbInfo->tarFd, "\0", 1);
 889         }
 890         /* Now do the verbose thing (or not) */
 891         if (tbInfo->verboseFlag==TRUE) {
 892                 FILE *vbFd = stdout;
 893                 if (tbInfo->tarFd == fileno(stdout))    // If the archive goes to stdout, verbose to stderr
 894                         vbFd = stderr;
 895                 fprintf(vbFd, "%s\n", header.name);
 896         }
 897
 898         return ( TRUE);
 899 }
 900
 901
 902 static int writeFileToTarball(const char *fileName, struct stat *statbuf, void* userData)
 903 {
 904         struct TarBallInfo *tbInfo = (struct TarBallInfo *)userData;
 905
 906         /* It is against the rules to archive a socket */
 907         if (S_ISSOCK(statbuf->st_mode)) {
 908                 errorMsg("%s: socket ignored\n", fileName);
 909                 return( TRUE);
 910         }
 911
 912         /* It is a bad idea to store the archive we are in the process of creating,
 913          * so check the device and inode to be sure that this particular file isn't
 914          * the new tarball */
 915         if (tbInfo->statBuf.st_dev == statbuf->st_dev &&
 916                         tbInfo->statBuf.st_ino == statbuf->st_ino) {
 917                 errorMsg("%s: file is the archive; skipping\n", fileName);
 918                 return( TRUE);
 919         }
 920
 921         if (strlen(fileName) >= NAME_SIZE) {
 922                 errorMsg(name_longer_than_foo, NAME_SIZE);
 923                 return ( TRUE);
 924         }
 925
 926         if (writeTarHeader(tbInfo, fileName, statbuf)==FALSE) {
 927                 return( FALSE);
 928         }
 929
 930         /* Now, if the file is a regular file, copy it out to the tarball */
 931         if (S_ISREG(statbuf->st_mode)) {
 932                 int  inputFileFd;
 933                 char buffer[BUFSIZ];
 934                 ssize_t size=0, readSize=0;
 935
 936                 /* open the file we want to archive, and make sure all is well */
 937                 if ((inputFileFd = open(fileName, O_RDONLY)) < 0) {
 938                         errorMsg("%s: Cannot open: %s\n", fileName, strerror(errno));
 939                         return( FALSE);
 940                 }
 941
 942                 /* write the file to the archive */
 943                 while ( (size = fullRead(inputFileFd, buffer, sizeof(buffer))) > 0 ) {
 944                         if (fullWrite(tbInfo->tarFd, buffer, size) != size ) {
 945                                 /* Output file seems to have a problem */
 946                                 errorMsg(io_error, fileName, strerror(errno));
 947                                 return( FALSE);
 948                         }
 949                         readSize+=size;
 950                 }
 951                 if (size == -1) {
 952                         errorMsg(io_error, fileName, strerror(errno));
 953                         return( FALSE);
 954                 }
 955                 /* Pad the file up to the tar block size */
 956                 for (; (readSize%TAR_BLOCK_SIZE) != 0; readSize++) {
 957                         write(tbInfo->tarFd, "\0", 1);
 958                 }
 959                 close( inputFileFd);
 960         }
 961
 962         return( TRUE);
 963 }
 964
 965 static int writeTarFile(const char* tarName, int verboseFlag, char **argv,
 966                 char** excludeList)
 967 {
 968         int tarFd=-1;
 969         int errorFlag=FALSE;
 970         ssize_t size;
 971         struct TarBallInfo tbInfo;
 972         tbInfo.verboseFlag = verboseFlag;
 973
 974         /* Make sure there is at least one file to tar up.  */
 975         if (*argv == NULL)
 976                 fatalError("Cowardly refusing to create an empty archive\n");
 977
 978         /* Open the tar file for writing.  */
 979         if (!strcmp(tarName, "-"))
 980                 tbInfo.tarFd = fileno(stdout);
 981         else
 982                 tbInfo.tarFd = open (tarName, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 983         if (tbInfo.tarFd < 0) {
 984                 errorMsg( "Error opening '%s': %s\n", tarName, strerror(errno));
 985                 return ( FALSE);
 986         }
 987         tbInfo.excludeList=excludeList;
 988         /* Store the stat info for the tarball's file, so
 989          * can avoid including the tarball into itself....  */
 990         if (fstat(tbInfo.tarFd, &tbInfo.statBuf) < 0)
 991                 fatalError(io_error, tarName, strerror(errno));
 992
 993         /* Set the umask for this process so it doesn't
 994          * screw up permission setting for us later. */
 995         umask(0);
 996
 997         /* Read the directory/files and iterate over them one at a time */
 998         while (*argv != NULL) {
 999                 if (recursiveAction(*argv++, TRUE, FALSE, FALSE,
1000                                         writeFileToTarball, writeFileToTarball,
1001                                         (void*) &tbInfo) == FALSE) {
1002                         errorFlag = TRUE;
1003                 }
1004         }
1005         /* Write two empty blocks to the end of the archive */
1006         for (size=0; size<(2*TAR_BLOCK_SIZE); size++) {
1007                 write(tbInfo.tarFd, "\0", 1);
1008         }
1009
1010         /* To be pedantically correct, we would check if the tarball
1011          * is smaller than 20 tar blocks, and pad it if it was smaller,
1012          * but that isn't necessary for GNU tar interoperability, and
1013          * so is considered a waste of space */
1014
1015         /* Hang up the tools, close up shop, head home */
1016         close(tarFd);
1017         if (errorFlag == TRUE) {
1018                 errorMsg("Error exit delayed from previous errors\n");
1019                 return(FALSE);
1020         }
1021         return( TRUE);
1022 }
1023
1024
1025 #endif
1026