1 /* vi: set sw=4 ts=4: */
4 * Mini tar implementation for busybox Note, that as of BusyBox 0.43 tar has
5 * been completely rewritten from the ground up. It still has remnents of the
6 * old code lying about, but it pretty different (i.e. cleaner, less global
9 * Copyright (C) 1999 by Lineo, inc.
10 * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
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.
18 * Based in part on the tar implementation in busybox-0.28
19 * Copyright (C) 1995 Bruce Perens
20 * This is free software under the GNU General Public License.
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.
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.
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
40 #define BB_DECLARE_EXTERN
41 #define bb_need_io_error
50 #include <sys/types.h>
51 #include <sys/sysmacros.h>
52 #include <sys/param.h> /* for PATH_MAX */
55 #ifdef BB_FEATURE_TAR_CREATE
57 static const char tar_usage[] =
58 "tar -[cxtvOf] [tarFileName] [FILE] ...\n\n"
59 "Create, extract, or list files from a tar file.\n\n"
62 "\tc=create, x=extract, t=list contents, v=verbose,\n"
63 "\tO=extract to stdout, f=tarfile or \"-\" for stdin\n";
67 static const char tar_usage[] =
68 "tar -[xtvOf] [tarFileName] [FILE] ...\n\n"
69 "Extract, or list files stored in a tar file. This\n"
70 "version of tar does not support creation of tar files.\n\n"
73 "\tx=extract, t=list contents, v=verbose,\n"
74 "\tO=extract to stdout, f=tarfile or \"-\" for stdin\n";
79 /* Tar file constants */
81 #define MAJOR(dev) (((dev)>>8)&0xff)
82 #define MINOR(dev) ((dev)&0xff)
86 /* POSIX tar Header Block, from POSIX 1003.1-1990 */
90 char name[100]; /* 0 */
91 char mode[8]; /* 100 */
92 char uid[8]; /* 108 */
93 char gid[8]; /* 116 */
94 char size[12]; /* 124 */
95 char mtime[12]; /* 136 */
96 char chksum[8]; /* 148 */
97 char typeflag; /* 156 */
98 char linkname[100]; /* 157 */
99 char magic[6]; /* 257 */
100 char version[2]; /* 263 */
101 char uname[32]; /* 265 */
102 char gname[32]; /* 297 */
103 char devmajor[8]; /* 329 */
104 char devminor[8]; /* 337 */
105 char prefix[155]; /* 345 */
108 typedef struct TarHeader TarHeader;
111 /* A few useful constants */
112 #define TAR_MAGIC "ustar" /* ustar and a null */
113 #define TAR_VERSION "00" /* 00 and no null */
114 #define TAR_MAGIC_LEN 6
115 #define TAR_VERSION_LEN 2
116 #define TAR_NAME_LEN 100
117 #define TAR_BLOCK_SIZE 512
119 /* A nice enum with all the possible tar file content types */
122 REGTYPE = '0', /* regular file */
123 REGTYPE0 = '\0', /* regular file (ancient bug compat)*/
124 LNKTYPE = '1', /* hard link */
125 SYMTYPE = '2', /* symbolic link */
126 CHRTYPE = '3', /* character special */
127 BLKTYPE = '4', /* block special */
128 DIRTYPE = '5', /* directory */
129 FIFOTYPE = '6', /* FIFO special */
130 CONTTYPE = '7', /* reserved */
132 typedef enum TarFileType TarFileType;
134 /* This struct ignores magic, non-numeric user name,
135 * non-numeric group name, and the checksum, since
136 * these are all ignored by BusyBox tar. */
139 int tarFd; /* An open file descriptor for reading from the tarball */
140 char * name; /* File name */
141 mode_t mode; /* Unix mode, including device bits. */
142 uid_t uid; /* Numeric UID */
143 gid_t gid; /* Numeric GID */
144 size_t size; /* Size of file */
145 time_t mtime; /* Last-modified time */
146 enum TarFileType type; /* Regular, directory, link, etc */
147 char * linkname; /* Name for symbolic and hard links */
148 long devmajor; /* Major number for special device */
149 long devminor; /* Minor number for special device */
151 typedef struct TarInfo TarInfo;
154 static const unsigned long TarChecksumOffset = (const unsigned long)&(((TarHeader *)0)->chksum);
157 /* Local procedures to restore files from a tar file. */
158 static int readTarFile(const char* tarName, int extractFlag, int listFlag,
159 int tostdoutFlag, int verboseFlag);
163 #ifdef BB_FEATURE_TAR_CREATE
164 /* Local procedures to save files into a tar file. */
165 static int writeTarFile(const char* tarName, int extractFlag, int listFlag,
166 int tostdoutFlag, int verboseFlag, int argc, char **argv);
167 static int putOctal(char *cp, int len, long value);
172 extern int tar_main(int argc, char **argv)
174 const char *tarName=NULL;
176 int listFlag = FALSE;
177 int extractFlag = FALSE;
178 int createFlag = FALSE;
179 int verboseFlag = FALSE;
180 int tostdoutFlag = FALSE;
190 options = (*argv++) + 1;
195 for (; *options; options++) {
199 fatalError( "Only one 'f' option allowed\n");
203 fatalError( "Option requires an argument: No file specified\n");
209 if (extractFlag == TRUE || createFlag == TRUE)
215 if (listFlag == TRUE || createFlag == TRUE)
220 if (extractFlag == TRUE || listFlag == TRUE)
238 fatalError( "Unknown tar flag '%c'\n"
239 "Try `tar --help' for more information\n", *options);
244 * Do the correct type of action supplying the rest of the
245 * command line arguments as the list of files to process.
247 if (createFlag == TRUE) {
248 #ifndef BB_FEATURE_TAR_CREATE
249 fatalError( "This version of tar was not compiled with tar creation support.\n");
251 exit(writeTarFile(tarName, extractFlag, listFlag, tostdoutFlag, verboseFlag, argc, argv));
254 exit(readTarFile(tarName, extractFlag, listFlag, tostdoutFlag, verboseFlag));
258 fatalError( "Exactly one of 'c', 'x' or 't' must be specified\n");
262 tarExtractRegularFile(TarInfo *header, int extractFlag, int tostdoutFlag)
266 size_t actualWriteSz;
268 size_t size = header->size;
269 int outFd=fileno(stdout);
271 /* Open the file to be written, if a file is supposed to be written */
272 if (extractFlag==TRUE && tostdoutFlag==FALSE) {
273 if ((outFd=open(header->name, O_CREAT|O_TRUNC|O_WRONLY, header->mode & ~S_IFMT)) < 0)
274 errorMsg(io_error, header->name, strerror(errno));
275 /* Create the path to the file, just in case it isn't there...
276 * This should not screw up path permissions or anything. */
277 createPath(header->name, 0777);
280 /* Write out the file, if we are supposed to be doing that */
283 if ( size > sizeof(buffer) )
284 writeSize = readSize = sizeof(buffer);
286 int mod = size % 512;
288 readSize = size + (512 - mod);
293 if ( (readSize = fullRead(header->tarFd, buffer, readSize)) <= 0 ) {
294 /* Tarball seems to have a problem */
295 errorMsg("tar: Unexpected EOF in archive\n");
298 if ( readSize < writeSize )
299 writeSize = readSize;
301 /* Write out the file, if we are supposed to be doing that */
302 if (extractFlag==TRUE) {
304 if ((actualWriteSz=fullWrite(outFd, buffer, writeSize)) != writeSize ) {
305 /* Output file seems to have a problem */
306 errorMsg(io_error, header->name, strerror(errno));
311 size -= actualWriteSz;
314 /* Now we are done writing the file out, so try
315 * and fix up the permissions and whatnot */
316 if (extractFlag==TRUE && tostdoutFlag==FALSE) {
318 /* Now set permissions etc for the new file */
319 fchown(outFd, header->uid, header->gid);
320 fchmod(outFd, header->mode & ~S_IFMT);
322 /* File must be closed before trying to change the date */
324 t.modtime = header->mtime;
325 utime(header->name, &t);
330 fixUpPermissions(TarInfo *header)
333 /* Now set permissions etc for the new file */
334 chown(header->name, header->uid, header->gid);
335 chmod(header->name, header->mode);
338 t.modtime = header->mtime;
339 utime(header->name, &t);
343 tarExtractDirectory(TarInfo *header, int extractFlag, int tostdoutFlag)
346 if (extractFlag==FALSE || tostdoutFlag==TRUE)
349 if (createPath(header->name, header->mode) != TRUE) {
350 errorMsg("Error creating directory '%s': %s", header->name, strerror(errno));
353 /* make the final component, just in case it was
354 * omitted by createPath() (which will skip the
355 * directory if it doesn't have a terminating '/') */
356 if (mkdir(header->name, header->mode) == 0) {
357 fixUpPermissions(header);
362 tarExtractHardLink(TarInfo *header, int extractFlag, int tostdoutFlag)
364 if (extractFlag==FALSE || tostdoutFlag==TRUE)
367 if (link(header->linkname, header->name) < 0) {
368 errorMsg("Error creating hard link '%s': %s\n", header->linkname, strerror(errno));
372 /* Now set permissions etc for the new directory */
373 fixUpPermissions(header);
377 tarExtractSymLink(TarInfo *header, int extractFlag, int tostdoutFlag)
379 if (extractFlag==FALSE || tostdoutFlag==TRUE)
383 if (symlink(header->linkname, header->name) < 0) {
384 errorMsg("Error creating symlink '%s': %s\n", header->linkname, strerror(errno));
387 /* Try to change ownership of the symlink.
388 * If libs doesn't support that, don't bother.
389 * Changing the pointed-to-file is the Wrong Thing(tm).
391 #if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
392 lchown(header->name, header->uid, header->gid);
395 /* Do not change permissions or date on symlink,
396 * since it changes the pointed to file instead. duh. */
398 fprintf(stderr, "Cannot create symbolic links\n");
403 tarExtractSpecial(TarInfo *header, int extractFlag, int tostdoutFlag)
405 if (extractFlag==FALSE || tostdoutFlag==TRUE)
408 if (S_ISCHR(header->mode) || S_ISBLK(header->mode) || S_ISSOCK(header->mode)) {
409 mknod(header->name, header->mode, makedev(header->devmajor, header->devminor));
410 } else if (S_ISFIFO(header->mode)) {
411 mkfifo(header->name, header->mode);
413 open(header->name, O_WRONLY | O_CREAT | O_TRUNC, header->mode);
416 /* Now set permissions etc for the new directory */
417 fixUpPermissions(header);
420 /* Read an octal value in a field of the specified width, with optional
421 * spaces on both sides of the number and with an optional null character
422 * at the end. Returns -1 on an illegal format. */
423 static long getOctal(const char *cp, int size)
427 for(;(size > 0) && (*cp == ' '); cp++, size--);
428 if ((size == 0) || !isOctal(*cp))
430 for(; (size > 0) && isOctal(*cp); size--) {
431 val = val * 8 + *cp++ - '0';
433 for (;(size > 0) && (*cp == ' '); cp++, size--);
434 if ((size > 0) && *cp)
440 /* Parse the tar header and fill in the nice struct with the details */
442 parseTarHeader(struct TarHeader *rawHeader, struct TarInfo *header)
446 unsigned char *s = (unsigned char *)rawHeader;
448 header->name = rawHeader->name;
449 header->mode = getOctal(rawHeader->mode, sizeof(rawHeader->mode));
450 header->uid = getOctal(rawHeader->uid, sizeof(rawHeader->uid));
451 header->gid = getOctal(rawHeader->gid, sizeof(rawHeader->gid));
452 header->size = getOctal(rawHeader->size, sizeof(rawHeader->size));
453 header->mtime = getOctal(rawHeader->mtime, sizeof(rawHeader->mtime));
454 chksum = getOctal(rawHeader->chksum, sizeof(rawHeader->chksum));
455 header->type = rawHeader->typeflag;
456 header->linkname = rawHeader->linkname;
457 header->devmajor = getOctal(rawHeader->devmajor, sizeof(rawHeader->devmajor));
458 header->devminor = getOctal(rawHeader->devminor, sizeof(rawHeader->devminor));
460 /* Check the checksum */
461 sum = ' ' * sizeof(rawHeader->chksum);
462 for ( i = TarChecksumOffset; i > 0; i-- )
464 s += sizeof(rawHeader->chksum);
465 for ( i = (512 - TarChecksumOffset - sizeof(rawHeader->chksum)); i > 0; i-- )
474 * Read a tar file and extract or list the specified files within it.
475 * If the list is empty than all files are extracted or listed.
477 static int readTarFile(const char* tarName, int extractFlag, int listFlag,
478 int tostdoutFlag, int verboseFlag)
484 int alreadyWarned=FALSE;
485 //int skipFileFlag=FALSE;
487 /* Open the tar file for reading. */
488 if (!strcmp(tarName, "-"))
489 tarFd = fileno(stdin);
491 tarFd = open(tarName, O_RDONLY);
493 errorMsg( "Error opening '%s': %s\n", tarName, strerror(errno));
497 /* Set the umask for this process so it doesn't
498 * screw up permission setting for us later. */
501 /* Read the tar file, and iterate over it one file at a time */
502 while ( (status = fullRead(tarFd, (char*)&rawHeader, TAR_BLOCK_SIZE)) == TAR_BLOCK_SIZE ) {
504 /* First, try to read the header */
505 if ( parseTarHeader(&rawHeader, &header) == FALSE ) {
507 if ( *(header.name) == '\0' ) {
511 errorMsg("Bad tar header, skipping\n");
515 if ( *(header.name) == '\0' )
518 /* Check for and relativify any absolute paths */
519 if ( *(header.name) == '/' ) {
521 while (*(header.name) == '/')
524 if (alreadyWarned == FALSE) {
525 errorMsg("Absolute path detected, removing leading slashes\n");
526 alreadyWarned = TRUE;
530 /* Special treatment if the list (-t) flag is on */
531 if (verboseFlag == TRUE && extractFlag == FALSE) {
534 struct tm *tm = localtime (&(header.mtime));
536 len=printf("%s %d/%-d ", modeString(header.mode), header.uid, header.gid);
537 if (header.type==CHRTYPE || header.type==BLKTYPE) {
538 len1=snprintf(buf, sizeof(buf), "%ld,%-ld ",
539 header.devmajor, header.devminor);
541 len1=snprintf(buf, sizeof(buf), "%d ", header.size);
543 /* Jump through some hoops to make the columns match up */
544 for(;(len+len1)<31;len++)
548 /* Use ISO 8610 time format */
550 printf ("%04d-%02d-%02d %02d:%02d:%02d ",
551 tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
552 tm->tm_hour, tm->tm_min, tm->tm_sec);
555 /* List contents if we are supposed to do that */
556 if (verboseFlag == TRUE || listFlag == TRUE) {
557 /* Now the normal listing */
558 printf("%s", header.name);
559 /* If this is a link, say so */
560 if (header.type==LNKTYPE)
561 printf(" link to %s", header.linkname);
562 else if (header.type==SYMTYPE)
563 printf(" -> %s", header.linkname);
568 /* See if we want to restore this file or not */
570 if (wantFileName(outName) == FALSE) {
575 /* If we got here, we can be certain we have a legitimate
576 * header to work with. So work with it. */
577 switch ( header.type ) {
580 /* If the name ends in a '/' then assume it is
581 * supposed to be a directory, and fall through */
582 if (header.name[strlen(header.name)-1] != '/') {
583 tarExtractRegularFile(&header, extractFlag, tostdoutFlag);
587 tarExtractDirectory( &header, extractFlag, tostdoutFlag);
590 tarExtractHardLink( &header, extractFlag, tostdoutFlag);
593 tarExtractSymLink( &header, extractFlag, tostdoutFlag);
598 tarExtractSpecial( &header, extractFlag, tostdoutFlag);
607 /* Bummer - we read a partial header */
608 errorMsg( "Error reading '%s': %s\n", tarName, strerror(errno));
614 /* Stuff to do when we are done */
617 if ( *(header.name) == '\0' ) {
618 if (errorFlag==FALSE)
625 #ifdef BB_FEATURE_TAR_CREATE
627 /* Put an octal string into the specified buffer.
628 * The number is zero and space padded and possibly null padded.
629 * Returns TRUE if successful. */
630 static int putOctal (char *cp, int len, long value)
636 /* Create a string of the specified length with an initial space,
637 * leading zeroes and the octal number, and a trailing null. */
638 tempString = tempBuffer;
640 sprintf (tempString, " %0*lo", len - 2, value);
642 tempLength = strlen (tempString) + 1;
644 /* If the string is too large, suppress the leading space. */
645 if (tempLength > len) {
650 /* If the string is still too large, suppress the trailing null. */
651 if (tempLength > len)
654 /* If the string is still too large, fail. */
655 if (tempLength > len)
658 /* Copy the string to the field. */
659 memcpy (cp, tempString, len);
664 static int fileAction(const char *fileName, struct stat *statbuf)
666 fprintf(stdout, "%s\n", fileName);
670 static int writeTarFile(const char* tarName, int extractFlag, int listFlag,
671 int tostdoutFlag, int verboseFlag, int argc, char **argv)
674 //int errorFlag=FALSE;
675 //TarHeader rawHeader;
677 //int alreadyWarned=FALSE;
678 char *directory = ".";
679 //int skipFileFlag=FALSE;
681 /* Open the tar file for writing. */
682 if (!strcmp(tarName, "-"))
683 tarFd = fileno(stdout);
685 tarFd = open (tarName, O_WRONLY | O_CREAT | O_TRUNC, 0644);
687 errorMsg( "Error opening '%s': %s\n", tarName, strerror(errno));
691 /* Set the umask for this process so it doesn't
692 * screw up permission setting for us later. */
695 /* Read the directory/files and iterate over them one at a time */
696 if (recursiveAction(directory, TRUE, FALSE, FALSE,
697 fileAction, fileAction) == FALSE) {
702 // TODO: DO STUFF HERE