1194 lines
25 KiB
C
1194 lines
25 KiB
C
/*
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* Mini tar implementation for busybox based on code taken from sash.
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*
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* Copyright (c) 1999 by David I. Bell
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* Permission is granted to use, distribute, or modify this source,
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* provided that this copyright notice remains intact.
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*
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* Permission to distribute this code under the GPL has been granted.
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*
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* Modified for busybox by Erik Andersen <andersee@debian.org>
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* Adjusted to grok stdin/stdout options.
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*
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* Modified to handle device special files by Matt Porter
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* <porter@debian.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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*/
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#include "internal.h"
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#include <stdio.h>
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#include <dirent.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <signal.h>
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#include <time.h>
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#include <sys/types.h>
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static const char tar_usage[] =
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"tar -[cxtvOf] [tarFileName] [FILE] ...\n\n"
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"Create, extract, or list files from a tar file\n\n"
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"Options:\n"
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"\tc=create, x=extract, t=list contents, v=verbose,\n"
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"\tO=extract to stdout, f=tarfile or \"-\" for stdin\n";
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/*
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* Tar file constants.
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*/
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#define TAR_BLOCK_SIZE 512
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#define TAR_NAME_SIZE 100
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/*
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* The POSIX (and basic GNU) tar header format.
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* This structure is always embedded in a TAR_BLOCK_SIZE sized block
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* with zero padding. We only process this information minimally.
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*/
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typedef struct {
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char name[TAR_NAME_SIZE];
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char mode[8];
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char uid[8];
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char gid[8];
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char size[12];
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char mtime[12];
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char checkSum[8];
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char typeFlag;
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char linkName[TAR_NAME_SIZE];
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char magic[6];
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char version[2];
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char uname[32];
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char gname[32];
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char devMajor[8];
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char devMinor[8];
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char prefix[155];
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} TarHeader;
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#define TAR_MAGIC "ustar"
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#define TAR_VERSION "00"
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#define TAR_TYPE_REGULAR '0'
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#define TAR_TYPE_HARD_LINK '1'
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#define TAR_TYPE_SOFT_LINK '2'
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/*
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* Static data.
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*/
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static int listFlag;
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static int extractFlag;
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static int createFlag;
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static int verboseFlag;
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static int tostdoutFlag;
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static int inHeader; // <- check me
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static int badHeader;
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static int errorFlag;
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static int skipFileFlag;
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static int warnedRoot;
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static int eofFlag;
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static long dataCc;
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static int outFd;
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static char outName[TAR_NAME_SIZE];
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/*
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* Static data associated with the tar file.
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*/
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static const char *tarName;
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static int tarFd;
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static dev_t tarDev;
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static ino_t tarInode;
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/*
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* Local procedures to restore files from a tar file.
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*/
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static void readTarFile (int fileCount, char **fileTable);
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static void readData (const char *cp, int count);
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static long getOctal (const char *cp, int len);
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static void readHeader (const TarHeader * hp,
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int fileCount, char **fileTable);
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/*
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* Local procedures to save files into a tar file.
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*/
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static void saveFile (const char *fileName, int seeLinks);
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static void saveRegularFile (const char *fileName,
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const struct stat *statbuf);
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static void saveDirectory (const char *fileName,
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const struct stat *statbuf);
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static int wantFileName (const char *fileName,
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int fileCount, char **fileTable);
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static void writeHeader (const char *fileName, const struct stat *statbuf);
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static void writeTarFile (int fileCount, char **fileTable);
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static void writeTarBlock (const char *buf, int len);
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static int putOctal (char *cp, int len, long value);
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extern int tar_main (int argc, char **argv)
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{
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const char *options;
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argc--;
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argv++;
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if (argc < 1)
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usage( tar_usage);
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errorFlag = FALSE;
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extractFlag = FALSE;
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createFlag = FALSE;
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listFlag = FALSE;
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verboseFlag = FALSE;
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tostdoutFlag = FALSE;
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tarName = NULL;
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tarDev = 0;
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tarInode = 0;
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tarFd = -1;
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/*
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* Parse the options.
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*/
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if (**argv == '-') {
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options = (*argv++) + 1;
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argc--;
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for (; *options; options++) {
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switch (*options) {
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case 'f':
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if (tarName != NULL) {
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fprintf (stderr, "Only one 'f' option allowed\n");
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exit (FALSE);
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}
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tarName = *argv++;
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argc--;
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break;
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case 't':
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listFlag = TRUE;
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break;
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case 'x':
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extractFlag = TRUE;
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break;
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case 'c':
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createFlag = TRUE;
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break;
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case 'v':
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verboseFlag = TRUE;
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break;
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case 'O':
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tostdoutFlag = TRUE;
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break;
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case '-':
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usage( tar_usage);
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break;
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default:
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fprintf (stderr, "Unknown tar flag '%c'\n"
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"Try `tar --help' for more information\n",
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*options);
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exit (FALSE);
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}
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}
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}
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/*
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* Validate the options.
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*/
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if (extractFlag + listFlag + createFlag != (TRUE+FALSE+FALSE)) {
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fprintf (stderr,
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"Exactly one of 'c', 'x' or 't' must be specified\n");
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exit (FALSE);
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}
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/*
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* Do the correct type of action supplying the rest of the
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* command line arguments as the list of files to process.
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*/
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if (createFlag==TRUE)
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writeTarFile (argc, argv);
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else
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readTarFile (argc, argv);
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if (errorFlag==TRUE)
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fprintf (stderr, "\n");
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exit (!errorFlag);
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}
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/*
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* Read a tar file and extract or list the specified files within it.
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* If the list is empty than all files are extracted or listed.
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*/
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static void readTarFile (int fileCount, char **fileTable)
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{
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const char *cp;
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int cc;
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int inCc;
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int blockSize;
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char buf[BUF_SIZE];
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skipFileFlag = FALSE;
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badHeader = FALSE;
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warnedRoot = FALSE;
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eofFlag = FALSE;
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inHeader = TRUE;
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inCc = 0;
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dataCc = 0;
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outFd = -1;
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blockSize = sizeof (buf);
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cp = buf;
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/*
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* Open the tar file for reading.
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*/
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if ((tarName == NULL) || !strcmp (tarName, "-")) {
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tarFd = STDIN;
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} else
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tarFd = open (tarName, O_RDONLY);
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if (tarFd < 0) {
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perror (tarName);
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errorFlag = TRUE;
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return;
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}
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/*
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* Read blocks from the file until an end of file header block
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* has been seen. (A real end of file from a read is an error.)
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*/
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while (eofFlag==FALSE) {
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/*
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* Read the next block of data if necessary.
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* This will be a large block if possible, which we will
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* then process in the small tar blocks.
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*/
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if (inCc <= 0) {
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cp = buf;
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inCc = fullRead (tarFd, buf, blockSize);
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if (inCc < 0) {
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perror (tarName);
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errorFlag = TRUE;
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goto done;
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}
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if (inCc == 0) {
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fprintf (stderr,
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"Unexpected end of file from \"%s\"", tarName);
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errorFlag = TRUE;
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goto done;
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}
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}
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/*
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* If we are expecting a header block then examine it.
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*/
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if (inHeader==TRUE) {
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readHeader ((const TarHeader *) cp, fileCount, fileTable);
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cp += TAR_BLOCK_SIZE;
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inCc -= TAR_BLOCK_SIZE;
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continue;
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}
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/*
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* We are currently handling the data for a file.
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* Process the minimum of the amount of data we have available
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* and the amount left to be processed for the file.
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*/
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cc = inCc;
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if (cc > dataCc)
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cc = dataCc;
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readData (cp, cc);
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/*
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* If the amount left isn't an exact multiple of the tar block
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* size then round it up to the next block boundary since there
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* is padding at the end of the file.
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*/
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if (cc % TAR_BLOCK_SIZE)
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cc += TAR_BLOCK_SIZE - (cc % TAR_BLOCK_SIZE);
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cp += cc;
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inCc -= cc;
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}
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done:
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/*
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* Close the tar file if needed.
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*/
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if ((tarFd >= 0) && (close (tarFd) < 0))
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perror (tarName);
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/*
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* Close the output file if needed.
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* This is only done here on a previous error and so no
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* message is required on errors.
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*/
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if (tostdoutFlag == FALSE) {
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if (outFd >= 0)
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(void) close (outFd);
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}
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}
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/*
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* Examine the header block that was just read.
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* This can specify the information for another file, or it can mark
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* the end of the tar file.
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*/
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static void
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readHeader (const TarHeader * hp, int fileCount, char **fileTable)
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{
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int mode;
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int uid;
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int gid;
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int checkSum;
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int major;
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int minor;
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long size;
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time_t mtime;
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const char *name;
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int cc;
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int hardLink;
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int softLink;
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int devFileFlag;
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/*
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* If the block is completely empty, then this is the end of the
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* archive file. If the name is null, then just skip this header.
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*/
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name = hp->name;
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if (*name == '\0') {
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for (cc = TAR_BLOCK_SIZE; cc > 0; cc--) {
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if (*name++)
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return;
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}
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eofFlag = TRUE;
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return;
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}
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/*
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* There is another file in the archive to examine.
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* Extract the encoded information and check it.
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*/
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mode = getOctal (hp->mode, sizeof (hp->mode));
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uid = getOctal (hp->uid, sizeof (hp->uid));
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gid = getOctal (hp->gid, sizeof (hp->gid));
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size = getOctal (hp->size, sizeof (hp->size));
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mtime = getOctal (hp->mtime, sizeof (hp->mtime));
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checkSum = getOctal (hp->checkSum, sizeof (hp->checkSum));
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major = getOctal (hp->devMajor, sizeof (hp->devMajor));
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minor = getOctal (hp->devMinor, sizeof (hp->devMinor));
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if ((mode < 0) || (uid < 0) || (gid < 0) || (size < 0)) {
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if (badHeader==FALSE)
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fprintf (stderr, "Bad tar header, skipping\n");
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badHeader = TRUE;
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return;
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}
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badHeader = FALSE;
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skipFileFlag = FALSE;
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devFileFlag = FALSE;
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/*
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* Check for the file modes.
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*/
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hardLink = ((hp->typeFlag == TAR_TYPE_HARD_LINK) ||
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(hp->typeFlag == TAR_TYPE_HARD_LINK - '0'));
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softLink = ((hp->typeFlag == TAR_TYPE_SOFT_LINK) ||
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(hp->typeFlag == TAR_TYPE_SOFT_LINK - '0'));
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/*
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* Check for a directory.
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*/
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if (name[strlen (name) - 1] == '/')
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mode |= S_IFDIR;
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/*
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* Check for absolute paths in the file.
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* If we find any, then warn the user and make them relative.
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*/
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if (*name == '/') {
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while (*name == '/')
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name++;
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|
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if (warnedRoot==FALSE) {
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fprintf (stderr,
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"Absolute path detected, removing leading slashes\n");
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}
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warnedRoot = TRUE;
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}
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/*
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* See if we want this file to be restored.
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* If not, then set up to skip it.
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*/
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if (wantFileName (name, fileCount, fileTable) == FALSE) {
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if ( !hardLink && !softLink && (S_ISREG (mode) || S_ISCHR (mode)
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|| S_ISBLK (mode) || S_ISSOCK(mode) || S_ISFIFO(mode) ) ) {
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inHeader = (size == 0)? TRUE : FALSE;
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dataCc = size;
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}
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skipFileFlag = TRUE;
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return;
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}
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/*
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* This file is to be handled.
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* If we aren't extracting then just list information about the file.
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*/
|
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if (extractFlag==FALSE) {
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if (verboseFlag==TRUE) {
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printf ("%s %3d/%-d %9ld %s %s", modeString (mode),
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uid, gid, size, timeString (mtime), name);
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} else
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printf ("%s", name);
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|
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if (hardLink)
|
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printf (" (link to \"%s\")", hp->linkName);
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else if (softLink)
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printf (" (symlink to \"%s\")", hp->linkName);
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else if (S_ISREG (mode) || S_ISCHR (mode) || S_ISBLK (mode) ||
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S_ISSOCK(mode) || S_ISFIFO(mode) ) {
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inHeader = (size == 0)? TRUE : FALSE;
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dataCc = size;
|
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}
|
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|
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printf ("\n");
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|
|
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return;
|
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}
|
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|
|
/*
|
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* We really want to extract the file.
|
|
*/
|
|
if (verboseFlag==TRUE)
|
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printf ("x %s\n", name);
|
|
|
|
if (hardLink) {
|
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if (link (hp->linkName, name) < 0)
|
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perror (name);
|
|
|
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return;
|
|
}
|
|
|
|
if (softLink) {
|
|
#ifdef S_ISLNK
|
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if (symlink (hp->linkName, name) < 0)
|
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perror (name);
|
|
#else
|
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fprintf (stderr, "Cannot create symbolic links\n");
|
|
#endif
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the file is a directory, then just create the path.
|
|
*/
|
|
if (S_ISDIR (mode)) {
|
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createPath (name, mode);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* There is a file to write.
|
|
* First create the path to it if necessary with a default permission.
|
|
*/
|
|
createPath (name, 0777);
|
|
|
|
inHeader = (size == 0)? TRUE : FALSE;
|
|
dataCc = size;
|
|
|
|
/*
|
|
* Start the output file.
|
|
*/
|
|
if (tostdoutFlag == TRUE)
|
|
outFd = STDOUT;
|
|
else {
|
|
if ( S_ISCHR(mode) || S_ISBLK(mode) || S_ISSOCK(mode) ) {
|
|
devFileFlag = TRUE;
|
|
outFd = mknod (name, mode, makedev(major, minor) );
|
|
}
|
|
else if (S_ISFIFO(mode) ) {
|
|
devFileFlag = TRUE;
|
|
outFd = mkfifo(name, mode);
|
|
} else {
|
|
outFd = open (name, O_WRONLY | O_CREAT | O_TRUNC, mode);
|
|
}
|
|
}
|
|
|
|
if (outFd < 0) {
|
|
perror (name);
|
|
skipFileFlag = TRUE;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the file is empty, then that's all we need to do.
|
|
*/
|
|
if (size == 0 && (tostdoutFlag == FALSE) && (devFileFlag == FALSE)) {
|
|
(void) close (outFd);
|
|
outFd = -1;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Handle a data block of some specified size that was read.
|
|
*/
|
|
static void readData (const char *cp, int count)
|
|
{
|
|
/*
|
|
* Reduce the amount of data left in this file.
|
|
* If there is no more data left, then we need to read
|
|
* the header again.
|
|
*/
|
|
dataCc -= count;
|
|
|
|
if (dataCc <= 0)
|
|
inHeader = TRUE;
|
|
|
|
/*
|
|
* If we aren't extracting files or this file is being
|
|
* skipped then do nothing more.
|
|
*/
|
|
if (extractFlag==FALSE || skipFileFlag==TRUE)
|
|
return;
|
|
|
|
/*
|
|
* Write the data to the output file.
|
|
*/
|
|
if (fullWrite (outFd, cp, count) < 0) {
|
|
perror (outName);
|
|
if (tostdoutFlag == FALSE) {
|
|
(void) close (outFd);
|
|
outFd = -1;
|
|
}
|
|
skipFileFlag = TRUE;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the write failed, close the file and disable further
|
|
* writes to this file.
|
|
*/
|
|
if (dataCc <= 0 && tostdoutFlag == FALSE) {
|
|
if (close (outFd))
|
|
perror (outName);
|
|
|
|
outFd = -1;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Write a tar file containing the specified files.
|
|
*/
|
|
static void writeTarFile (int fileCount, char **fileTable)
|
|
{
|
|
struct stat statbuf;
|
|
|
|
/*
|
|
* Make sure there is at least one file specified.
|
|
*/
|
|
if (fileCount <= 0) {
|
|
fprintf (stderr, "No files specified to be saved\n");
|
|
errorFlag = TRUE;
|
|
}
|
|
|
|
/*
|
|
* Create the tar file for writing.
|
|
*/
|
|
if ((tarName == NULL) || !strcmp (tarName, "-")) {
|
|
tostdoutFlag = TRUE;
|
|
tarFd = STDOUT;
|
|
} else
|
|
tarFd = open (tarName, O_WRONLY | O_CREAT | O_TRUNC, 0666);
|
|
|
|
if (tarFd < 0) {
|
|
perror (tarName);
|
|
errorFlag = TRUE;
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Get the device and inode of the tar file for checking later.
|
|
*/
|
|
if (fstat (tarFd, &statbuf) < 0) {
|
|
perror (tarName);
|
|
errorFlag = TRUE;
|
|
goto done;
|
|
}
|
|
|
|
tarDev = statbuf.st_dev;
|
|
tarInode = statbuf.st_ino;
|
|
|
|
/*
|
|
* Append each file name into the archive file.
|
|
* Follow symbolic links for these top level file names.
|
|
*/
|
|
while (errorFlag==FALSE && (fileCount-- > 0)) {
|
|
saveFile (*fileTable++, FALSE);
|
|
}
|
|
|
|
/*
|
|
* Now write an empty block of zeroes to end the archive.
|
|
*/
|
|
writeTarBlock ("", 1);
|
|
|
|
|
|
done:
|
|
/*
|
|
* Close the tar file and check for errors if it was opened.
|
|
*/
|
|
if ((tostdoutFlag == FALSE) && (tarFd >= 0) && (close (tarFd) < 0))
|
|
perror (tarName);
|
|
}
|
|
|
|
|
|
/*
|
|
* Save one file into the tar file.
|
|
* If the file is a directory, then this will recursively save all of
|
|
* the files and directories within the directory. The seeLinks
|
|
* flag indicates whether or not we want to see symbolic links as
|
|
* they really are, instead of blindly following them.
|
|
*/
|
|
static void saveFile (const char *fileName, int seeLinks)
|
|
{
|
|
int status;
|
|
int mode;
|
|
struct stat statbuf;
|
|
|
|
if (verboseFlag==TRUE)
|
|
printf ("a %s\n", fileName);
|
|
|
|
/*
|
|
* Check that the file name will fit in the header.
|
|
*/
|
|
if (strlen (fileName) >= TAR_NAME_SIZE) {
|
|
fprintf (stderr, "%s: File name is too long\n", fileName);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Find out about the file.
|
|
*/
|
|
#ifdef S_ISLNK
|
|
if (seeLinks==TRUE)
|
|
status = lstat (fileName, &statbuf);
|
|
else
|
|
#endif
|
|
status = stat (fileName, &statbuf);
|
|
|
|
if (status < 0) {
|
|
perror (fileName);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Make sure we aren't trying to save our file into itself.
|
|
*/
|
|
if ((statbuf.st_dev == tarDev) && (statbuf.st_ino == tarInode)) {
|
|
fprintf (stderr, "Skipping saving of archive file itself\n");
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Check the type of file.
|
|
*/
|
|
mode = statbuf.st_mode;
|
|
|
|
if (S_ISDIR (mode)) {
|
|
saveDirectory (fileName, &statbuf);
|
|
|
|
return;
|
|
}
|
|
if (S_ISREG (mode)) {
|
|
saveRegularFile (fileName, &statbuf);
|
|
|
|
return;
|
|
}
|
|
|
|
/* Some day add support for tarring these up... but not today. :) */
|
|
// if (S_ISLNK(mode) || S_ISFIFO(mode) || S_ISBLK(mode) || S_ISCHR (mode) ) {
|
|
// fprintf (stderr, "%s: This version of tar can't store this type of file\n", fileName);
|
|
// }
|
|
|
|
/*
|
|
* The file is a strange type of file, ignore it.
|
|
*/
|
|
fprintf (stderr, "%s: not a directory or regular file\n", fileName);
|
|
}
|
|
|
|
|
|
/*
|
|
* Save a regular file to the tar file.
|
|
*/
|
|
static void
|
|
saveRegularFile (const char *fileName, const struct stat *statbuf)
|
|
{
|
|
int sawEof;
|
|
int fileFd;
|
|
int cc;
|
|
int dataCount;
|
|
long fullDataCount;
|
|
char data[TAR_BLOCK_SIZE * 16];
|
|
|
|
/*
|
|
* Open the file for reading.
|
|
*/
|
|
fileFd = open (fileName, O_RDONLY);
|
|
|
|
if (fileFd < 0) {
|
|
perror (fileName);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Write out the header for the file.
|
|
*/
|
|
writeHeader (fileName, statbuf);
|
|
|
|
/*
|
|
* Write the data blocks of the file.
|
|
* We must be careful to write the amount of data that the stat
|
|
* buffer indicated, even if the file has changed size. Otherwise
|
|
* the tar file will be incorrect.
|
|
*/
|
|
fullDataCount = statbuf->st_size;
|
|
sawEof = FALSE;
|
|
|
|
while (fullDataCount > 0) {
|
|
/*
|
|
* Get the amount to write this iteration which is
|
|
* the minumum of the amount left to write and the
|
|
* buffer size.
|
|
*/
|
|
dataCount = sizeof (data);
|
|
|
|
if (dataCount > fullDataCount)
|
|
dataCount = (int) fullDataCount;
|
|
|
|
/*
|
|
* Read the data from the file if we haven't seen the
|
|
* end of file yet.
|
|
*/
|
|
cc = 0;
|
|
|
|
if (sawEof==FALSE) {
|
|
cc = fullRead (fileFd, data, dataCount);
|
|
|
|
if (cc < 0) {
|
|
perror (fileName);
|
|
|
|
(void) close (fileFd);
|
|
errorFlag = TRUE;
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If the file ended too soon, complain and set
|
|
* a flag so we will zero fill the rest of it.
|
|
*/
|
|
if (cc < dataCount) {
|
|
fprintf (stderr,
|
|
"%s: Short read - zero filling", fileName);
|
|
|
|
sawEof = TRUE;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Zero fill the rest of the data if necessary.
|
|
*/
|
|
if (cc < dataCount)
|
|
memset (data + cc, 0, dataCount - cc);
|
|
|
|
/*
|
|
* Write the buffer to the TAR file.
|
|
*/
|
|
writeTarBlock (data, dataCount);
|
|
|
|
fullDataCount -= dataCount;
|
|
}
|
|
|
|
/*
|
|
* Close the file.
|
|
*/
|
|
if ((tostdoutFlag == FALSE) && close (fileFd) < 0)
|
|
fprintf (stderr, "%s: close: %s\n", fileName, strerror (errno));
|
|
}
|
|
|
|
|
|
/*
|
|
* Save a directory and all of its files to the tar file.
|
|
*/
|
|
static void saveDirectory (const char *dirName, const struct stat *statbuf)
|
|
{
|
|
DIR *dir;
|
|
struct dirent *entry;
|
|
int needSlash;
|
|
char fullName[NAME_MAX];
|
|
|
|
/*
|
|
* Construct the directory name as used in the tar file by appending
|
|
* a slash character to it.
|
|
*/
|
|
strcpy (fullName, dirName);
|
|
strcat (fullName, "/");
|
|
|
|
/*
|
|
* Write out the header for the directory entry.
|
|
*/
|
|
writeHeader (fullName, statbuf);
|
|
|
|
/*
|
|
* Open the directory.
|
|
*/
|
|
dir = opendir (dirName);
|
|
|
|
if (dir == NULL) {
|
|
fprintf (stderr, "Cannot read directory \"%s\": %s\n",
|
|
dirName, strerror (errno));
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* See if a slash is needed.
|
|
*/
|
|
needSlash = (*dirName && (dirName[strlen (dirName) - 1] != '/'));
|
|
|
|
/*
|
|
* Read all of the directory entries and check them,
|
|
* except for the current and parent directory entries.
|
|
*/
|
|
while (errorFlag==FALSE && ((entry = readdir (dir)) != NULL)) {
|
|
if ((strcmp (entry->d_name, ".") == 0) ||
|
|
(strcmp (entry->d_name, "..") == 0)) {
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Build the full path name to the file.
|
|
*/
|
|
strcpy (fullName, dirName);
|
|
|
|
if (needSlash)
|
|
strcat (fullName, "/");
|
|
|
|
strcat (fullName, entry->d_name);
|
|
|
|
/*
|
|
* Write this file to the tar file, noticing whether or not
|
|
* the file is a symbolic link.
|
|
*/
|
|
saveFile (fullName, TRUE);
|
|
}
|
|
|
|
/*
|
|
* All done, close the directory.
|
|
*/
|
|
closedir (dir);
|
|
}
|
|
|
|
|
|
/*
|
|
* Write a tar header for the specified file name and status.
|
|
* It is assumed that the file name fits.
|
|
*/
|
|
static void writeHeader (const char *fileName, const struct stat *statbuf)
|
|
{
|
|
long checkSum;
|
|
const unsigned char *cp;
|
|
int len;
|
|
TarHeader header;
|
|
|
|
/*
|
|
* Zero the header block in preparation for filling it in.
|
|
*/
|
|
memset ((char *) &header, 0, sizeof (header));
|
|
|
|
/*
|
|
* Fill in the header.
|
|
*/
|
|
strcpy (header.name, fileName);
|
|
|
|
strncpy (header.magic, TAR_MAGIC, sizeof (header.magic));
|
|
strncpy (header.version, TAR_VERSION, sizeof (header.version));
|
|
|
|
putOctal (header.mode, sizeof (header.mode), statbuf->st_mode & 0777);
|
|
putOctal (header.uid, sizeof (header.uid), statbuf->st_uid);
|
|
putOctal (header.gid, sizeof (header.gid), statbuf->st_gid);
|
|
putOctal (header.size, sizeof (header.size), statbuf->st_size);
|
|
putOctal (header.mtime, sizeof (header.mtime), statbuf->st_mtime);
|
|
|
|
header.typeFlag = TAR_TYPE_REGULAR;
|
|
|
|
/*
|
|
* Calculate and store the checksum.
|
|
* This is the sum of all of the bytes of the header,
|
|
* with the checksum field itself treated as blanks.
|
|
*/
|
|
memset (header.checkSum, ' ', sizeof (header.checkSum));
|
|
|
|
cp = (const unsigned char *) &header;
|
|
len = sizeof (header);
|
|
checkSum = 0;
|
|
|
|
while (len-- > 0)
|
|
checkSum += *cp++;
|
|
|
|
putOctal (header.checkSum, sizeof (header.checkSum), checkSum);
|
|
|
|
/*
|
|
* Write the tar header.
|
|
*/
|
|
writeTarBlock ((const char *) &header, sizeof (header));
|
|
}
|
|
|
|
|
|
/*
|
|
* Write data to one or more blocks of the tar file.
|
|
* The data is always padded out to a multiple of TAR_BLOCK_SIZE.
|
|
* The errorFlag static variable is set on an error.
|
|
*/
|
|
static void writeTarBlock (const char *buf, int len)
|
|
{
|
|
int partialLength;
|
|
int completeLength;
|
|
char fullBlock[TAR_BLOCK_SIZE];
|
|
|
|
/*
|
|
* If we had a write error before, then do nothing more.
|
|
*/
|
|
if (errorFlag==TRUE)
|
|
return;
|
|
|
|
/*
|
|
* Get the amount of complete and partial blocks.
|
|
*/
|
|
partialLength = len % TAR_BLOCK_SIZE;
|
|
completeLength = len - partialLength;
|
|
|
|
/*
|
|
* Write all of the complete blocks.
|
|
*/
|
|
if ((completeLength > 0) && !fullWrite (tarFd, buf, completeLength)) {
|
|
perror (tarName);
|
|
|
|
errorFlag = TRUE;
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If there are no partial blocks left, we are done.
|
|
*/
|
|
if (partialLength == 0)
|
|
return;
|
|
|
|
/*
|
|
* Copy the partial data into a complete block, and pad the rest
|
|
* of it with zeroes.
|
|
*/
|
|
memcpy (fullBlock, buf + completeLength, partialLength);
|
|
memset (fullBlock + partialLength, 0, TAR_BLOCK_SIZE - partialLength);
|
|
|
|
/*
|
|
* Write the last complete block.
|
|
*/
|
|
if (!fullWrite (tarFd, fullBlock, TAR_BLOCK_SIZE)) {
|
|
perror (tarName);
|
|
|
|
errorFlag = TRUE;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Read an octal value in a field of the specified width, with optional
|
|
* spaces on both sides of the number and with an optional null character
|
|
* at the end. Returns -1 on an illegal format.
|
|
*/
|
|
static long getOctal (const char *cp, int len)
|
|
{
|
|
long val;
|
|
|
|
while ((len > 0) && (*cp == ' ')) {
|
|
cp++;
|
|
len--;
|
|
}
|
|
|
|
if ((len == 0) || !isOctal (*cp))
|
|
return -1;
|
|
|
|
val = 0;
|
|
|
|
while ((len > 0) && isOctal (*cp)) {
|
|
val = val * 8 + *cp++ - '0';
|
|
len--;
|
|
}
|
|
|
|
while ((len > 0) && (*cp == ' ')) {
|
|
cp++;
|
|
len--;
|
|
}
|
|
|
|
if ((len > 0) && *cp)
|
|
return -1;
|
|
|
|
return val;
|
|
}
|
|
|
|
|
|
/*
|
|
* Put an octal string into the specified buffer.
|
|
* The number is zero and space padded and possibly null padded.
|
|
* Returns TRUE if successful.
|
|
*/
|
|
static int putOctal (char *cp, int len, long value)
|
|
{
|
|
int tempLength;
|
|
char *tempString;
|
|
char tempBuffer[32];
|
|
|
|
/*
|
|
* Create a string of the specified length with an initial space,
|
|
* leading zeroes and the octal number, and a trailing null.
|
|
*/
|
|
tempString = tempBuffer;
|
|
|
|
sprintf (tempString, " %0*lo", len - 2, value);
|
|
|
|
tempLength = strlen (tempString) + 1;
|
|
|
|
/*
|
|
* If the string is too large, suppress the leading space.
|
|
*/
|
|
if (tempLength > len) {
|
|
tempLength--;
|
|
tempString++;
|
|
}
|
|
|
|
/*
|
|
* If the string is still too large, suppress the trailing null.
|
|
*/
|
|
if (tempLength > len)
|
|
tempLength--;
|
|
|
|
/*
|
|
* If the string is still too large, fail.
|
|
*/
|
|
if (tempLength > len)
|
|
return FALSE;
|
|
|
|
/*
|
|
* Copy the string to the field.
|
|
*/
|
|
memcpy (cp, tempString, len);
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
|
|
/*
|
|
* See if the specified file name belongs to one of the specified list
|
|
* of path prefixes. An empty list implies that all files are wanted.
|
|
* Returns TRUE if the file is selected.
|
|
*/
|
|
static int
|
|
wantFileName (const char *fileName, int fileCount, char **fileTable)
|
|
{
|
|
const char *pathName;
|
|
int fileLength;
|
|
int pathLength;
|
|
|
|
/*
|
|
* If there are no files in the list, then the file is wanted.
|
|
*/
|
|
if (fileCount == 0)
|
|
return TRUE;
|
|
|
|
fileLength = strlen (fileName);
|
|
|
|
/*
|
|
* Check each of the test paths.
|
|
*/
|
|
while (fileCount-- > 0) {
|
|
pathName = *fileTable++;
|
|
|
|
pathLength = strlen (pathName);
|
|
|
|
if (fileLength < pathLength)
|
|
continue;
|
|
|
|
if (memcmp (fileName, pathName, pathLength) != 0)
|
|
continue;
|
|
|
|
if ((fileLength == pathLength) || (fileName[pathLength] == '/')) {
|
|
return TRUE;
|
|
}
|
|
}
|
|
|
|
return FALSE;
|
|
}
|
|
|
|
|
|
|
|
/* END CODE */
|