More little stuff.
[oweals/busybox.git] / tar.c
diff --git a/tar.c b/tar.c
index 87b5d2176ee185b7ad746c17ab2aad5721c80c07..9b3cb7d8142e2a226513a9f48c8dd82e48d1cf00 100644 (file)
--- a/tar.c
+++ b/tar.c
@@ -1,18 +1,23 @@
 /* vi: set sw=4 ts=4: */
 /*
- * Mini tar implementation for busybox based on code taken from sash.
+ * Mini tar implementation for busybox 
  *
- * Copyright (c) 1999 by David I. Bell
- * Permission is granted to use, distribute, or modify this source,
- * provided that this copyright notice remains intact.
+ * Note, that as of BusyBox-0.43, tar has been completely rewritten from the
+ * ground up.  It still has remnents of the old code lying about, but it is
+ * very different now (i.e. cleaner, less global variables, etc)
  *
- * Permission to distribute this code under the GPL has been granted.
+ * Copyright (C) 2000 by Lineo, inc.
+ * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
  *
- * Modified for busybox by Erik Andersen <andersee@debian.org>
- * Adjusted to grok stdin/stdout options.
+ * Based in part in the tar implementation in sash
+ *  Copyright (c) 1999 by David I. Bell
+ *  Permission is granted to use, distribute, or modify this source,
+ *  provided that this copyright notice remains intact.
+ *  Permission to distribute sash derived code under the GPL has been granted.
  *
- * Modified to handle device special files by Matt Porter
- * <porter@debian.org>
+ * Based in part on the tar implementation from busybox-0.28
+ *  Copyright (C) 1995 Bruce Perens
+ *  This is free software under the GNU General Public License.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -32,6 +37,9 @@
 
 
 #include "internal.h"
+#define BB_DECLARE_EXTERN
+#define bb_need_io_error
+#include "messages.c"
 #include <stdio.h>
 #include <dirent.h>
 #include <errno.h>
 #include <sys/param.h>                 /* for PATH_MAX */
 
 
-#ifdef BB_FEATURE_TAR_CREATE
-
 static const char tar_usage[] =
-       "tar -[cxtvOf] [tarFileName] [FILE] ...\n\n"
-       "Create, extract, or list files from a tar file.\n\n"
-       "Options:\n"
-
-       "\tc=create, x=extract, t=list contents, v=verbose,\n"
-       "\tO=extract to stdout, f=tarfile or \"-\" for stdin\n";
-
+#ifdef BB_FEATURE_TAR_CREATE
+       "tar -[cxtvO] "
 #else
-
-static const char tar_usage[] =
-       "tar -[xtvOf] [tarFileName] [FILE] ...\n\n"
-       "Extract, or list files stored in a tar file.  This\n"
-       "version of tar does not support creation of tar files.\n\n"
-       "Options:\n"
-
-       "\tx=extract, t=list contents, v=verbose,\n"
-       "\tO=extract to stdout, f=tarfile or \"-\" for stdin\n";
-
+       "tar -[xtvO] "
 #endif
-
-
-/*
- * Tar file constants.
- */
-#define TAR_BLOCK_SIZE 512
-#define TAR_NAME_SIZE  100
-
-
-/*
- * The POSIX (and basic GNU) tar header format.
- * This structure is always embedded in a TAR_BLOCK_SIZE sized block
- * with zero padding.  We only process this information minimally.
- */
-typedef struct {
-       char name[TAR_NAME_SIZE];
-       char mode[8];
-       char uid[8];
-       char gid[8];
-       char size[12];
-       char mtime[12];
-       char checkSum[8];
-       char typeFlag;
-       char linkName[TAR_NAME_SIZE];
-       char magic[6];
-       char version[2];
-       char uname[32];
-       char gname[32];
-       char devMajor[8];
-       char devMinor[8];
-       char prefix[155];
-} TarHeader;
-
-#define        TAR_MAGIC       "ustar"
-#define        TAR_VERSION     "00"
-
-#define        TAR_TYPE_REGULAR        '0'
-#define        TAR_TYPE_HARD_LINK      '1'
-#define        TAR_TYPE_SOFT_LINK      '2'
-
-
-/*
- * Static data.
- */
-static int listFlag;
-static int extractFlag;
-static int createFlag;
-static int verboseFlag;
-static int tostdoutFlag;
-
-static int inHeader;                   // <- check me
-static int badHeader;
-static int errorFlag;
-static int skipFileFlag;
-static int warnedRoot;
-static int eofFlag;
-static long dataCc;
-static int outFd;
-static const char *outName;
-
-static int mode;
-static int uid;
-static int gid;
-static time_t mtime;
-
-/*
- * Static data associated with the tar file.
- */
-static const char *tarName;
-static int tarFd;
-static dev_t tarDev;
-static ino_t tarInode;
-
-
-/*
- * Local procedures to restore files from a tar file.
- */
-static void readTarFile(int fileCount, char **fileTable);
-static void readData(const char *cp, int count);
-static long getOctal(const char *cp, int len);
-
-static void readHeader(const TarHeader * hp,
-
-                                          int fileCount, char **fileTable);
-
-static int wantFileName(const char *fileName,
-
-                                               int fileCount, char **fileTable);
-
+#if defined BB_FEATURE_TAR_EXCLUDE
+       "[--exclude File] "
+#endif
+       "[-f tarFile] [FILE] ...\n\n"
+       "Create, extract, or list files from a tar file.  Note that\n"
+       "this version of tar treats hard links as separate files.\n\n"
+       "Main operation mode:\n"
 #ifdef BB_FEATURE_TAR_CREATE
-/*
- * Local procedures to save files into a tar file.
- */
-static void saveFile(const char *fileName, int seeLinks);
-
-static void saveRegularFile(const char *fileName,
-
-                                                       const struct stat *statbuf);
+       "\tc\t\tcreate\n"
+#endif
+       "\tx\t\textract\n"
+       "\tt\t\tlist\n"
+       "File selection:\n"
+       "\tf\t\tname of tarfile or \"-\" for stdin\n"
+       "\tO\t\textract to stdout\n"
+#if defined BB_FEATURE_TAR_EXCLUDE
+       "\t--exclude\tfile to exclude\n"
+#endif
+       "Informative output:\n"
+       "\tv\t\tverbosely list files processed\n"
+       ;
+
+/* Tar file constants  */
+#ifndef MAJOR
+#define MAJOR(dev) (((dev)>>8)&0xff)
+#define MINOR(dev) ((dev)&0xff)
+#endif
 
-static void saveDirectory(const char *fileName,
 
-                                                 const struct stat *statbuf);
+/* POSIX tar Header Block, from POSIX 1003.1-1990  */
+struct TarHeader
+{
+                                /* byte offset */
+       char name[100];               /*   0-99 */
+       char mode[8];                 /* 100-107 */
+       char uid[8];                  /* 108-115 */
+       char gid[8];                  /* 116-123 */
+       char size[12];                /* 124-135 */
+       char mtime[12];               /* 136-147 */
+       char chksum[8];               /* 148-155 */
+       char typeflag;                /* 156-156 */
+       char linkname[100];           /* 157-256 */
+       char magic[6];                /* 257-262 */
+       char version[2];              /* 263-264 */
+       char uname[32];               /* 265-296 */
+       char gname[32];               /* 297-328 */
+       char devmajor[8];             /* 329-336 */
+       char devminor[8];             /* 337-344 */
+       char prefix[155];             /* 345-499 */
+       char padding[12];             /* 500-512 (pad to exactly the TAR_BLOCK_SIZE) */
+};
+typedef struct TarHeader TarHeader;
+
+
+/* A few useful constants */
+#define TAR_MAGIC          "ustar"        /* ustar and a null */
+#define TAR_VERSION        "  "           /* Be compatable with GNU tar format */
+#define TAR_MAGIC_LEN       6
+#define TAR_VERSION_LEN     2
+#define TAR_BLOCK_SIZE      512
+
+/* A nice enum with all the possible tar file content types */
+enum TarFileType 
+{
+       REGTYPE  = '0',            /* regular file */
+       REGTYPE0 = '\0',           /* regular file (ancient bug compat)*/
+       LNKTYPE  = '1',            /* hard link */
+       SYMTYPE  = '2',            /* symbolic link */
+       CHRTYPE  = '3',            /* character special */
+       BLKTYPE  = '4',            /* block special */
+       DIRTYPE  = '5',            /* directory */
+       FIFOTYPE = '6',            /* FIFO special */
+       CONTTYPE = '7',            /* reserved */
+};
+typedef enum TarFileType TarFileType;
+
+/* This struct ignores magic, non-numeric user name, 
+ * non-numeric group name, and the checksum, since
+ * these are all ignored by BusyBox tar. */ 
+struct TarInfo
+{
+       int              tarFd;          /* An open file descriptor for reading from the tarball */
+       char *           name;           /* File name */
+       mode_t           mode;           /* Unix mode, including device bits. */
+       uid_t            uid;            /* Numeric UID */
+       gid_t            gid;            /* Numeric GID */
+       size_t           size;           /* Size of file */
+       time_t           mtime;          /* Last-modified time */
+       enum TarFileType type;           /* Regular, directory, link, etc */
+       char *           linkname;       /* Name for symbolic and hard links */
+       long             devmajor;       /* Major number for special device */
+       long             devminor;       /* Minor number for special device */
+};
+typedef struct TarInfo TarInfo;
+
+/* Local procedures to restore files from a tar file.  */
+static int readTarFile(const char* tarName, int extractFlag, int listFlag, 
+               int tostdoutFlag, int verboseFlag, char** excludeList);
 
-static void writeHeader(const char *fileName, const struct stat *statbuf);
 
-static void writeTarFile(int fileCount, char **fileTable);
-static void writeTarBlock(const char *buf, int len);
-static int putOctal(char *cp, int len, long value);
 
+#ifdef BB_FEATURE_TAR_CREATE
+/* Local procedures to save files into a tar file.  */
+static int writeTarFile(const char* tarName, int tostdoutFlag, 
+               int verboseFlag, int argc, char **argv, char** excludeList);
 #endif
 
 
 extern int tar_main(int argc, char **argv)
 {
-       const char *options;
-
-       argc--;
-       argv++;
-
-       if (argc < 1)
+       char** excludeList=NULL;
+#if defined BB_FEATURE_TAR_EXCLUDE
+       int excludeListSize=0;
+#endif
+       const char *tarName=NULL;
+       int listFlag     = FALSE;
+       int extractFlag  = FALSE;
+       int createFlag   = FALSE;
+       int verboseFlag  = FALSE;
+       int tostdoutFlag = FALSE;
+       int stopIt;
+
+       if (argc <= 1)
                usage(tar_usage);
 
+       /* Parse any options */
+       while (--argc > 0 && **(++argv) == '-') {
+               stopIt=FALSE;
+               while (stopIt==FALSE && *(++(*argv))) {
+                       switch (**argv) {
+                               case 'f':
+                                       if (--argc == 0) {
+                                               fatalError( "Option requires an argument: No file specified\n");
+                                       }
+                                       if (tarName != NULL)
+                                               fatalError( "Only one 'f' option allowed\n");
+                                       tarName = *(++argv);
+                                       if (tarName == NULL)
+                                               fatalError( "Option requires an argument: No file specified\n");
+                                       stopIt=TRUE;
+                                       break;
+
+                               case 't':
+                                       if (extractFlag == TRUE || createFlag == TRUE)
+                                               goto flagError;
+                                       listFlag = TRUE;
+                                       break;
+
+                               case 'x':
+                                       if (listFlag == TRUE || createFlag == TRUE)
+                                               goto flagError;
+                                       extractFlag = TRUE;
+                                       break;
+                               case 'c':
+                                       if (extractFlag == TRUE || listFlag == TRUE)
+                                               goto flagError;
+                                       createFlag = TRUE;
+                                       break;
+
+                               case 'v':
+                                       verboseFlag = TRUE;
+                                       break;
+
+                               case 'O':
+                                       tostdoutFlag = TRUE;
+                                       tarName = "-";
+                                       break;
+                               case '-':
+#if defined BB_FEATURE_TAR_EXCLUDE
+                                       if (strcmp(*argv, "-exclude")==0) {
+                                               if (--argc == 0) {
+                                                       fatalError( "Option requires an argument: No file specified\n");
+                                               }
+                                               excludeList=realloc( excludeList, sizeof(char**) * (excludeListSize+2));
+                                               excludeList[excludeListSize] = *(++argv);
+                                               /* Remove leading "/"s */
+                                               if (*excludeList[excludeListSize] =='/') {
+                                                       excludeList[excludeListSize] = (excludeList[excludeListSize])+1;
+                                               }
+                                               if (excludeList[excludeListSize++] == NULL)
+                                                       fatalError( "Option requires an argument: No file specified\n");
+                                               /* Tack a NULL onto the end of the list */
+                                               excludeList[excludeListSize] = NULL;
+                                               stopIt=TRUE;
+                                               break;
+                                       }
+#endif
+                                       usage(tar_usage);
+                                       break;
 
-       errorFlag = FALSE;
-       extractFlag = FALSE;
-       createFlag = FALSE;
-       listFlag = FALSE;
-       verboseFlag = FALSE;
-       tostdoutFlag = FALSE;
-       tarName = NULL;
-       tarDev = 0;
-       tarInode = 0;
-       tarFd = -1;
-
-       /* 
-        * Parse the options.
-        */
-       if (**argv == '-')
-               options = (*argv++) + 1;
-       else
-               options = (*argv++);
-       argc--;
-
-       for (; *options; options++) {
-               switch (*options) {
-               case 'f':
-                       if (tarName != NULL) {
-                               fprintf(stderr, "Only one 'f' option allowed\n");
-
-                               exit(FALSE);
+                               default:
+                                       fatalError( "Unknown tar flag '%c'\n" 
+                                                       "Try `tar --help' for more information\n", **argv);
                        }
-
-                       tarName = *argv++;
-                       argc--;
-
-                       break;
-
-               case 't':
-                       if (extractFlag == TRUE || createFlag == TRUE)
-                               goto flagError;
-                       listFlag = TRUE;
-                       break;
-
-               case 'x':
-                       if (listFlag == TRUE || createFlag == TRUE)
-                               goto flagError;
-                       extractFlag = TRUE;
-                       break;
-               case 'c':
-                       if (extractFlag == TRUE || listFlag == TRUE)
-                               goto flagError;
-                       createFlag = TRUE;
-                       break;
-
-               case 'v':
-                       verboseFlag = TRUE;
-                       break;
-
-               case 'O':
-                       tostdoutFlag = TRUE;
-                       break;
-
-               case '-':
-                       usage(tar_usage);
-                       break;
-
-               default:
-                       fprintf(stderr, "Unknown tar flag '%c'\n"
-                                       "Try `tar --help' for more information\n", *options);
-                       exit(FALSE);
                }
        }
 
@@ -265,1016 +261,734 @@ extern int tar_main(int argc, char **argv)
         */
        if (createFlag == TRUE) {
 #ifndef BB_FEATURE_TAR_CREATE
-               fprintf(stderr,
-                               "This version of tar was not compiled with tar creation support.\n");
-               exit(FALSE);
+               fatalError( "This version of tar was not compiled with tar creation support.\n");
 #else
-               writeTarFile(argc, argv);
+               exit(writeTarFile(tarName, tostdoutFlag, verboseFlag, argc, argv, excludeList));
 #endif
        } else {
-               readTarFile(argc, argv);
-       }
-       if (errorFlag == TRUE) {
-               fprintf(stderr, "\n");
+               exit(readTarFile(tarName, extractFlag, listFlag, tostdoutFlag, verboseFlag, excludeList));
        }
-       exit(!errorFlag);
 
   flagError:
-       fprintf(stderr, "Exactly one of 'c', 'x' or 't' must be specified\n");
-       exit(FALSE);
+       fatalError( "Exactly one of 'c', 'x' or 't' must be specified\n");
 }
-
-
-/*
- * Read a tar file and extract or list the specified files within it.
- * If the list is empty than all files are extracted or listed.
- */
-static void readTarFile(int fileCount, char **fileTable)
+                                       
+static void
+fixUpPermissions(TarInfo *header)
 {
-       const char *cp;
-       int cc;
-       int inCc;
-       int blockSize;
-       char buf[BUF_SIZE];
-
-       skipFileFlag = FALSE;
-       badHeader = FALSE;
-       warnedRoot = FALSE;
-       eofFlag = FALSE;
-       inHeader = TRUE;
-       inCc = 0;
-       dataCc = 0;
-       outFd = -1;
-       blockSize = sizeof(buf);
-       cp = buf;
-
-       /* 
-        * Open the tar file for reading.
-        */
-       if ((tarName == NULL) || !strcmp(tarName, "-")) {
-               tarFd = fileno(stdin);
-       } else
-               tarFd = open(tarName, O_RDONLY);
-
-       if (tarFd < 0) {
-               perror(tarName);
-               errorFlag = TRUE;
-               return;
-       }
-
-       /* 
-        * Read blocks from the file until an end of file header block
-        * has been seen.  (A real end of file from a read is an error.)
-        */
-       while (eofFlag == FALSE) {
-               /* 
-                * Read the next block of data if necessary.
-                * This will be a large block if possible, which we will
-                * then process in the small tar blocks.
-                */
-               if (inCc <= 0) {
-                       cp = buf;
-                       inCc = fullRead(tarFd, buf, blockSize);
-
-                       if (inCc < 0) {
-                               perror(tarName);
-                               errorFlag = TRUE;
-                               goto done;
-                       }
-
-                       if (inCc == 0) {
-                               fprintf(stderr,
-                                               "Unexpected end of file from \"%s\"", tarName);
-                               errorFlag = TRUE;
-                               goto done;
-                       }
+       struct utimbuf t;
+       /* Now set permissions etc for the new file */
+       chown(header->name, header->uid, header->gid);
+       chmod(header->name, header->mode);
+       /* Reset the time */
+       t.actime = time(0);
+       t.modtime = header->mtime;
+       utime(header->name, &t);
+}
+                               
+static int
+tarExtractRegularFile(TarInfo *header, int extractFlag, int tostdoutFlag)
+{
+       size_t  writeSize;
+       size_t  readSize;
+       size_t  actualWriteSz;
+       char    buffer[BUFSIZ];
+       size_t  size = header->size;
+       int outFd=fileno(stdout);
+
+       /* Open the file to be written, if a file is supposed to be written */
+       if (extractFlag==TRUE && tostdoutFlag==FALSE) {
+               if ((outFd=open(header->name, O_CREAT|O_TRUNC|O_WRONLY, header->mode & ~S_IFMT)) < 0)
+                       errorMsg(io_error, header->name, strerror(errno)); 
+               /* Create the path to the file, just in case it isn't there...
+                * This should not screw up path permissions or anything. */
+               createPath(header->name, 0777);
+       }
+
+       /* Write out the file, if we are supposed to be doing that */
+       while ( size > 0 ) {
+               actualWriteSz=0;
+               if ( size > sizeof(buffer) )
+                       writeSize = readSize = sizeof(buffer);
+               else {
+                       int mod = size % 512;
+                       if ( mod != 0 )
+                               readSize = size + (512 - mod);
+                       else
+                               readSize = size;
+                       writeSize = size;
                }
-
-               /* 
-                * If we are expecting a header block then examine it.
-                */
-               if (inHeader == TRUE) {
-                       readHeader((const TarHeader *) cp, fileCount, fileTable);
-
-                       cp += TAR_BLOCK_SIZE;
-                       inCc -= TAR_BLOCK_SIZE;
-
-                       continue;
+               if ( (readSize = fullRead(header->tarFd, buffer, readSize)) <= 0 ) {
+                       /* Tarball seems to have a problem */
+                       errorMsg("tar: Unexpected EOF in archive\n"); 
+                       return( FALSE);
                }
+               if ( readSize < writeSize )
+                       writeSize = readSize;
 
-               /* 
-                * We are currently handling the data for a file.
-                * Process the minimum of the amount of data we have available
-                * and the amount left to be processed for the file.
-                */
-               cc = inCc;
-
-               if (cc > dataCc)
-                       cc = dataCc;
+               /* Write out the file, if we are supposed to be doing that */
+               if (extractFlag==TRUE) {
 
-               readData(cp, cc);
-
-               /* 
-                * If the amount left isn't an exact multiple of the tar block
-                * size then round it up to the next block boundary since there
-                * is padding at the end of the file.
-                */
-               if (cc % TAR_BLOCK_SIZE)
-                       cc += TAR_BLOCK_SIZE - (cc % TAR_BLOCK_SIZE);
+                       if ((actualWriteSz=fullWrite(outFd, buffer, writeSize)) != writeSize ) {
+                               /* Output file seems to have a problem */
+                               errorMsg(io_error, header->name, strerror(errno)); 
+                               return( FALSE);
+                       }
+               } else {
+                       actualWriteSz=writeSize;
+               }
 
-               cp += cc;
-               inCc -= cc;
+               size -= actualWriteSz;
        }
 
-  done:
-       /* 
-        * Close the tar file if needed.
-        */
-       if ((tarFd >= 0) && (close(tarFd) < 0))
-               perror(tarName);
-
-       /* 
-        * Close the output file if needed.
-        * This is only done here on a previous error and so no
-        * message is required on errors.
-        */
-       if (tostdoutFlag == FALSE) {
-               if (outFd >= 0) {
-                       close(outFd);
-               }
+       /* Now we are done writing the file out, so try 
+        * and fix up the permissions and whatnot */
+       if (extractFlag==TRUE && tostdoutFlag==FALSE) {
+               close(outFd);
+               fixUpPermissions(header);
        }
+       return( TRUE);
 }
 
-
-/*
- * Examine the header block that was just read.
- * This can specify the information for another file, or it can mark
- * the end of the tar file.
- */
-static void
-readHeader(const TarHeader * hp, int fileCount, char **fileTable)
+static int
+tarExtractDirectory(TarInfo *header, int extractFlag, int tostdoutFlag)
 {
-       int checkSum;
-       int cc;
-       int hardLink;
-       int softLink;
-       int devFileFlag;
-       unsigned int major;
-       unsigned int minor;
-       long size;
-       struct utimbuf utb;
-
-       /* 
-        * If the block is completely empty, then this is the end of the
-        * archive file.  If the name is null, then just skip this header.
-        */
-       outName = hp->name;
-
-       if (*outName == '\0') {
-               for (cc = TAR_BLOCK_SIZE; cc > 0; cc--) {
-                       if (*outName++)
-                               return;
-               }
 
-               eofFlag = TRUE;
+       if (extractFlag==FALSE || tostdoutFlag==TRUE)
+               return( TRUE);
 
-               return;
+       if (createPath(header->name, header->mode) != TRUE) {
+               errorMsg("tar: %s: Cannot mkdir: %s\n", 
+                               header->name, strerror(errno)); 
+               return( FALSE);
        }
-
-       /* 
-        * There is another file in the archive to examine.
-        * Extract the encoded information and check it.
-        */
-       mode = getOctal(hp->mode, sizeof(hp->mode));
-       uid = getOctal(hp->uid, sizeof(hp->uid));
-       gid = getOctal(hp->gid, sizeof(hp->gid));
-       size = getOctal(hp->size, sizeof(hp->size));
-       mtime = getOctal(hp->mtime, sizeof(hp->mtime));
-       checkSum = getOctal(hp->checkSum, sizeof(hp->checkSum));
-       major = getOctal(hp->devMajor, sizeof(hp->devMajor));
-       minor = getOctal(hp->devMinor, sizeof(hp->devMinor));
-
-       if ((mode < 0) || (uid < 0) || (gid < 0) || (size < 0)) {
-               if (badHeader == FALSE)
-                       fprintf(stderr, "Bad tar header, skipping\n");
-
-               badHeader = TRUE;
-
-               return;
+       /* make the final component, just in case it was
+        * omitted by createPath() (which will skip the
+        * directory if it doesn't have a terminating '/') */
+       if (mkdir(header->name, header->mode) == 0) {
+               fixUpPermissions(header);
        }
+       return( TRUE);
+}
 
-       badHeader = FALSE;
-       skipFileFlag = FALSE;
-       devFileFlag = FALSE;
-
-       /* 
-        * Check for the file modes.
-        */
-       hardLink = ((hp->typeFlag == TAR_TYPE_HARD_LINK) ||
-                               (hp->typeFlag == TAR_TYPE_HARD_LINK - '0'));
-
-       softLink = ((hp->typeFlag == TAR_TYPE_SOFT_LINK) ||
-                               (hp->typeFlag == TAR_TYPE_SOFT_LINK - '0'));
-
-       /* 
-        * Check for a directory.
-        */
-       if (outName[strlen(outName) - 1] == '/')
-               mode |= S_IFDIR;
-
-       /* 
-        * Check for absolute paths in the file.
-        * If we find any, then warn the user and make them relative.
-        */
-       if (*outName == '/') {
-               while (*outName == '/')
-                       outName++;
-
-               if (warnedRoot == FALSE) {
-                       fprintf(stderr,
-                                       "Absolute path detected, removing leading slashes\n");
-               }
-
-               warnedRoot = TRUE;
-       }
-
-       /* 
-        * See if we want this file to be restored.
-        * If not, then set up to skip it.
-        */
-       if (wantFileName(outName, fileCount, fileTable) == FALSE) {
-               if (!hardLink && !softLink && (S_ISREG(mode) || S_ISCHR(mode)
-                                                                          || S_ISBLK(mode) || S_ISSOCK(mode)
-                                                                          || S_ISFIFO(mode))) {
-                       inHeader = (size == 0) ? TRUE : FALSE;
-                       dataCc = size;
-               }
-
-               skipFileFlag = TRUE;
+static int
+tarExtractHardLink(TarInfo *header, int extractFlag, int tostdoutFlag)
+{
+       if (extractFlag==FALSE || tostdoutFlag==TRUE)
+               return( TRUE);
 
-               return;
+       if (link(header->linkname, header->name) < 0) {
+               errorMsg("tar: %s: Cannot create hard link to '%s': %s\n", 
+                               header->name, header->linkname, strerror(errno)); 
+               return( FALSE);
        }
 
-       /* 
-        * This file is to be handled.
-        * If we aren't extracting then just list information about the file.
-        */
-       if (extractFlag == FALSE) {
-               if (verboseFlag == TRUE) {
-                       printf("%s %3d/%-d ", modeString(mode), uid, gid);
-                       if (S_ISCHR(mode) || S_ISBLK(mode))
-                               printf("%4d,%4d %s ", major, minor, timeString(mtime));
-                       else
-                               printf("%9ld %s ", size, timeString(mtime));
-               }
-               printf("%s", outName);
-
-               if (hardLink)
-                       printf(" (link to \"%s\")", hp->linkName);
-               else if (softLink)
-                       printf(" (symlink to \"%s\")", hp->linkName);
-               else if (S_ISREG(mode) || S_ISCHR(mode) || S_ISBLK(mode) ||
-                                S_ISSOCK(mode) || S_ISFIFO(mode)) {
-                       inHeader = (size == 0) ? TRUE : FALSE;
-                       dataCc = size;
-               }
+       /* Now set permissions etc for the new directory */
+       fixUpPermissions(header);
+       return( TRUE);
+}
 
-               printf("\n");
+static int
+tarExtractSymLink(TarInfo *header, int extractFlag, int tostdoutFlag)
+{
+       if (extractFlag==FALSE || tostdoutFlag==TRUE)
+               return( TRUE);
 
-               return;
+#ifdef S_ISLNK
+       if (symlink(header->linkname, header->name) < 0) {
+               errorMsg("tar: %s: Cannot create symlink to '%s': %s\n", 
+                               header->name, header->linkname, strerror(errno)); 
+               return( FALSE);
        }
-
-       /* 
-        * We really want to extract the file.
+       /* Try to change ownership of the symlink.
+        * If libs doesn't support that, don't bother.
+        * Changing the pointed-to-file is the Wrong Thing(tm).
         */
-       if (verboseFlag == TRUE)
-               printf("x %s\n", outName);
-
-       if (hardLink) {
-               if (link(hp->linkName, outName) < 0) {
-                       perror(outName);
-                       return;
-               }
-               /* Set the file time */
-               utb.actime = mtime;
-               utb.modtime = mtime;
-               utime(outName, &utb);
-               /* Set the file permissions */
-               chown(outName, uid, gid);
-               chmod(outName, mode);
-               return;
-       }
-
-       if (softLink) {
-#ifdef S_ISLNK
-               if (symlink(hp->linkName, outName) < 0) {
-                       perror(outName);
-                       return;
-               }
-               /* Try to change ownership of the symlink.
-                * If libs doesn't support that, don't bother.
-                * Changing the pointed-to file is the Wrong Thing(tm).
-                */
 #if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
-               lchown(outName, uid, gid);
+       lchown(header->name, header->uid, header->gid);
 #endif
 
-               /* Do not change permissions or date on symlink,
-                * since it changes the pointed to file instead.  duh. */
+       /* Do not change permissions or date on symlink,
+        * since it changes the pointed to file instead.  duh. */
 #else
-               fprintf(stderr, "Cannot create symbolic links\n");
+       errorMsg("tar: %s: Cannot create symlink to '%s': %s\n", 
+                       header->name, header->linkname, 
+                       "symlinks not supported"); 
 #endif
-               return;
-       }
-
-       /* Set the umask for this process so it doesn't 
-        * screw things up. */
-       umask(0);
-
-       /* 
-        * If the file is a directory, then just create the path.
-        */
-       if (S_ISDIR(mode)) {
-               if (createPath(outName, mode) == TRUE) {
-                       /* Set the file time */
-                       utb.actime = mtime;
-                       utb.modtime = mtime;
-                       utime(outName, &utb);
-                       /* Set the file permissions */
-                       chown(outName, uid, gid);
-                       chmod(outName, mode);
-                       return;
-               }
-               return;
-       }
-
-       /* 
-        * There is a file to write.
-        * First create the path to it if necessary with default permissions.
-        */
-       createPath(outName, 0777);
-
-       inHeader = (size == 0) ? TRUE : FALSE;
-       dataCc = size;
+       return( TRUE);
+}
 
-       /* 
-        * Start the output file.
-        */
-       if (tostdoutFlag == TRUE)
-               outFd = fileno(stdout);
-       else {
-               if (S_ISCHR(mode) || S_ISBLK(mode) || S_ISSOCK(mode)) {
-                       devFileFlag = TRUE;
-                       outFd = mknod(outName, mode, makedev(major, minor));
-               } else if (S_ISFIFO(mode)) {
-                       devFileFlag = TRUE;
-                       outFd = mkfifo(outName, mode);
-               } else {
-                       outFd = open(outName, O_WRONLY | O_CREAT | O_TRUNC, mode);
+static int
+tarExtractSpecial(TarInfo *header, int extractFlag, int tostdoutFlag)
+{
+       if (extractFlag==FALSE || tostdoutFlag==TRUE)
+               return( TRUE);
+
+       if (S_ISCHR(header->mode) || S_ISBLK(header->mode) || S_ISSOCK(header->mode)) {
+               if (mknod(header->name, header->mode, makedev(header->devmajor, header->devminor)) < 0) {
+                       errorMsg("tar: %s: Cannot mknod: %s\n",
+                               header->name, strerror(errno)); 
+                       return( FALSE);
                }
-               if (outFd < 0) {
-                       perror(outName);
-                       skipFileFlag = TRUE;
-                       return;
+       } else if (S_ISFIFO(header->mode)) {
+               if (mkfifo(header->name, header->mode) < 0) {
+                       errorMsg("tar: %s: Cannot mkfifo: %s\n",
+                               header->name, strerror(errno)); 
+                       return( FALSE);
                }
-               /* Set the file time */
-               utb.actime = mtime;
-               utb.modtime = mtime;
-               utime(outName, &utb);
-               /* Set the file permissions */
-               chown(outName, uid, gid);
-               chmod(outName, mode);
        }
 
-
-       /* 
-        * If the file is empty, then that's all we need to do.
-        */
-       if (size == 0 && (tostdoutFlag == FALSE) && (devFileFlag == FALSE)) {
-               close(outFd);
-               outFd = -1;
-       }
+       /* Now set permissions etc for the new directory */
+       fixUpPermissions(header);
+       return( TRUE);
 }
 
-
-/*
- * Handle a data block of some specified size that was read.
- */
-static void readData(const char *cp, int count)
+/* 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 size)
 {
-       /* 
-        * 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;
+       long val = 0;
 
-       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) {
-                       close(outFd);
-                       outFd = -1;
-               }
-               skipFileFlag = TRUE;
-               return;
-       }
-
-       /* 
-        * Check if we are done writing to the file now.
-        */
-       if (dataCc <= 0 && tostdoutFlag == FALSE) {
-               struct utimbuf utb;
-
-               if (close(outFd))
-                       perror(outName);
-
-               /* Set the file time */
-               utb.actime = mtime;
-               utb.modtime = mtime;
-               utime(outName, &utb);
-               /* Set the file permissions */
-               chown(outName, uid, gid);
-               chmod(outName, mode);
-
-               outFd = -1;
+       for(;(size > 0) && (*cp == ' '); cp++, size--);
+       if ((size == 0) || !isOctal(*cp))
+               return -1;
+       for(; (size > 0) && isOctal(*cp); size--) {
+               val = val * 8 + *cp++ - '0';
        }
+       for (;(size > 0) && (*cp == ' '); cp++, size--);
+       if ((size > 0) && *cp)
+               return -1;
+       return val;
 }
 
 
-/*
- * 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.
- */
+/* Parse the tar header and fill in the nice struct with the details */
 static int
-wantFileName(const char *fileName, int fileCount, char **fileTable)
+readTarHeader(struct TarHeader *rawHeader, struct TarInfo *header)
 {
-       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);
+       int i;
+       long chksum, sum=0;
+       unsigned char *s = (unsigned char *)rawHeader;
 
-               if (fileLength < pathLength)
-                       continue;
+       header->name  = rawHeader->name;
+       /* Check for and relativify any absolute paths */
+       if ( *(header->name) == '/' ) {
+               static int alreadyWarned=FALSE;
 
-               if (memcmp(fileName, pathName, pathLength) != 0)
-                       continue;
+               while (*(header->name) == '/')
+                       ++*(header->name);
 
-               if ((fileLength == pathLength) || (fileName[pathLength] == '/')) {
-                       return TRUE;
+               if (alreadyWarned == FALSE) {
+                       errorMsg("tar: Removing leading '/' from member names\n");
+                       alreadyWarned = TRUE;
                }
        }
 
-       return FALSE;
+       header->mode  = getOctal(rawHeader->mode, sizeof(rawHeader->mode));
+       header->uid   =  getOctal(rawHeader->uid, sizeof(rawHeader->uid));
+       header->gid   =  getOctal(rawHeader->gid, sizeof(rawHeader->gid));
+       header->size  = getOctal(rawHeader->size, sizeof(rawHeader->size));
+       header->mtime = getOctal(rawHeader->mtime, sizeof(rawHeader->mtime));
+       chksum = getOctal(rawHeader->chksum, sizeof(rawHeader->chksum));
+       header->type  = rawHeader->typeflag;
+       header->linkname  = rawHeader->linkname;
+       header->devmajor  = getOctal(rawHeader->devmajor, sizeof(rawHeader->devmajor));
+       header->devminor  = getOctal(rawHeader->devminor, sizeof(rawHeader->devminor));
+
+       /* Check the checksum */
+       for (i = sizeof(*rawHeader); i-- != 0;) {
+               sum += *s++;
+       }
+       /* Remove the effects of the checksum field (replace 
+        * with blanks for the purposes of the checksum) */
+       s = rawHeader->chksum;
+       for (i = sizeof(rawHeader->chksum) ; i-- != 0;) {
+               sum -= *s++;
+       }
+       sum += ' ' * sizeof(rawHeader->chksum);
+       if (sum == chksum )
+               return ( TRUE);
+       return( FALSE);
 }
 
+
 /*
- * 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.
+ * Read a tar file and extract or list the specified files within it.
+ * If the list is empty than all files are extracted or listed.
  */
-static long getOctal(const char *cp, int len)
+static int readTarFile(const char* tarName, int extractFlag, int listFlag, 
+               int tostdoutFlag, int verboseFlag, char** excludeList)
 {
-       long val;
+       int status, tarFd=-1;
+       int errorFlag=FALSE;
+       TarHeader rawHeader;
+       TarInfo header;
+#if defined BB_FEATURE_TAR_EXCLUDE
+       char** tmpList;
+#endif
 
-       while ((len > 0) && (*cp == ' ')) {
-               cp++;
-               len--;
+       /* Open the tar file for reading.  */
+       if (!strcmp(tarName, "-"))
+               tarFd = fileno(stdin);
+       else
+               tarFd = open(tarName, O_RDONLY);
+       if (tarFd < 0) {
+               errorMsg( "Error opening '%s': %s\n", tarName, strerror(errno));
+               return ( FALSE);
        }
 
-       if ((len == 0) || !isOctal(*cp))
-               return -1;
+       /* Set the umask for this process so it doesn't 
+        * screw up permission setting for us later. */
+       umask(0);
 
-       val = 0;
+       /* Read the tar file, and iterate over it one file at a time */
+       while ( (status = fullRead(tarFd, (char*)&rawHeader, TAR_BLOCK_SIZE)) == TAR_BLOCK_SIZE ) {
+
+               /* First, try to read the header */
+               if ( readTarHeader(&rawHeader, &header) == FALSE ) {
+                       if ( *(header.name) == '\0' ) {
+                               goto endgame;
+                       } else {
+                               errorFlag=TRUE;
+                               errorMsg("Bad tar header, skipping\n");
+                               continue;
+                       }
+               }
+               if ( *(header.name) == '\0' )
+                               goto endgame;
+               header.tarFd = tarFd;
+
+#if defined BB_FEATURE_TAR_EXCLUDE
+               {
+                       int skipFlag=FALSE;
+                       /* Check for excluded files....  */
+                       for (tmpList=excludeList; tmpList && *tmpList; tmpList++) {
+                               /* Do some extra hoop jumping for when directory names
+                                * end in '/' but the entry in tmpList doesn't */
+                               if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
+                                                       header.name[strlen(header.name)-1]=='/'
+                                                       && strncmp( *tmpList, header.name, 
+                                                               MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
+                                       /* If it is a regular file, pretend to extract it with
+                                        * the extractFlag set to FALSE, so the junk in the tarball
+                                        * is properly skipped over */
+                                       if ( header.type==REGTYPE || header.type==REGTYPE0 ) {
+                                                       tarExtractRegularFile(&header, FALSE, FALSE);
+                                       }
+                                       skipFlag=TRUE;
+                                       break;
+                               }
+                       }
+                       /* There are not the droids you're looking for, move along */
+                       if (skipFlag==TRUE)
+                               continue;
+               }
+#endif
+               /* Special treatment if the list (-t) flag is on */
+               if (verboseFlag == TRUE && extractFlag == FALSE) {
+                       int len, len1;
+                       char buf[35];
+                       struct tm *tm = localtime (&(header.mtime));
+
+                       len=printf("%s ", modeString(header.mode));
+                       memset(buf, 0, 8*sizeof(char));
+                       my_getpwuid(buf, header.uid);
+                       if (! *buf)
+                               len+=printf("%d", header.uid);
+                       else
+                               len+=printf("%s", buf);
+                       memset(buf, 0, 8*sizeof(char));
+                       my_getgrgid(buf, header.gid);
+                       if (! *buf)
+                               len+=printf("/%-d ", header.gid);
+                       else
+                               len+=printf("/%-s ", buf);
 
-       while ((len > 0) && isOctal(*cp)) {
-               val = val * 8 + *cp++ - '0';
-               len--;
-       }
+                       if (header.type==CHRTYPE || header.type==BLKTYPE) {
+                               len1=snprintf(buf, sizeof(buf), "%ld,%-ld ", 
+                                               header.devmajor, header.devminor);
+                       } else {
+                               len1=snprintf(buf, sizeof(buf), "%d ", header.size);
+                       }
+                       /* Jump through some hoops to make the columns match up */
+                       for(;(len+len1)<31;len++)
+                               printf(" ");
+                       printf(buf);
+
+                       /* Use ISO 8610 time format */
+                       if (tm) { 
+                               printf ("%04d-%02d-%02d %02d:%02d:%02d ", 
+                                               tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday, 
+                                               tm->tm_hour, tm->tm_min, tm->tm_sec);
+                       }
+               }
+               /* List contents if we are supposed to do that */
+               if (verboseFlag == TRUE || listFlag == TRUE) {
+                       /* Now the normal listing */
+                       printf("%s", header.name);
+               }
+               if (verboseFlag == TRUE && listFlag == TRUE) {
+                       /* If this is a link, say so */
+                       if (header.type==LNKTYPE)
+                               printf(" link to %s", header.linkname);
+                       else if (header.type==SYMTYPE)
+                               printf(" -> %s", header.linkname);
+               }
+               if (verboseFlag == TRUE || listFlag == TRUE) {
+                       printf("\n");
+               }
 
-       while ((len > 0) && (*cp == ' ')) {
-               cp++;
-               len--;
+               /* Remove any clutter lying in our way */
+               unlink( header.name);
+
+               /* If we got here, we can be certain we have a legitimate 
+                * header to work with.  So work with it.  */
+               switch ( header.type ) {
+                       case REGTYPE:
+                       case REGTYPE0:
+                               /* If the name ends in a '/' then assume it is
+                                * supposed to be a directory, and fall through */
+                               if (header.name[strlen(header.name)-1] != '/') {
+                                       if (tarExtractRegularFile(&header, extractFlag, tostdoutFlag)==FALSE)
+                                               errorFlag=TRUE;
+                                       break;
+                               }
+                       case DIRTYPE:
+                               if (tarExtractDirectory( &header, extractFlag, tostdoutFlag)==FALSE)
+                                       errorFlag=TRUE;
+                               break;
+                       case LNKTYPE:
+                               if (tarExtractHardLink( &header, extractFlag, tostdoutFlag)==FALSE)
+                                       errorFlag=TRUE;
+                               break;
+                       case SYMTYPE:
+                               if (tarExtractSymLink( &header, extractFlag, tostdoutFlag)==FALSE)
+                                       errorFlag=TRUE;
+                               break;
+                       case CHRTYPE:
+                       case BLKTYPE:
+                       case FIFOTYPE:
+                               if (tarExtractSpecial( &header, extractFlag, tostdoutFlag)==FALSE)
+                                       errorFlag=TRUE;
+                               break;
+                       default:
+                               close( tarFd);
+                               return( FALSE);
+               }
        }
-
-       if ((len > 0) && *cp)
-               return -1;
-
-       return val;
+       close(tarFd);
+       if (status > 0) {
+               /* Bummer - we read a partial header */
+               errorMsg( "Error reading '%s': %s\n", tarName, strerror(errno));
+               return ( FALSE);
+       }
+       else if (errorFlag==TRUE) {
+               errorMsg( "tar: Error exit delayed from previous errors\n");
+               return( FALSE);
+       } else 
+               return( status);
+
+       /* Stuff to do when we are done */
+endgame:
+       close( tarFd);
+       if ( *(header.name) == '\0' ) {
+               if (errorFlag==TRUE)
+                       errorMsg( "tar: Error exit delayed from previous errors\n");
+               else
+                       return( TRUE);
+       } 
+       return( FALSE);
 }
 
 
-
-
-/* From here to the end of the file is the tar writing stuff.
- * If you do not have BB_FEATURE_TAR_CREATE defined, this will
- * not be built.
- * */
 #ifdef BB_FEATURE_TAR_CREATE
 
-/*
- * Write a tar file containing the specified files.
- */
-static void writeTarFile(int fileCount, char **fileTable)
+/* Some info to be carried along when creating a new tarball */
+struct TarBallInfo
 {
-       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;
-       }
+       char* fileName;               /* File name of the tarball */
+       int tarFd;                    /* Open-for-write file descriptor
+                                                                        for the tarball */
+       struct stat statBuf;          /* Stat info for the tarball, letting
+                                                                        us know the inode and device that the
+                                                                        tarball lives, so we can avoid trying 
+                                                                        to include the tarball into itself */
+       int verboseFlag;              /* Whether to print extra stuff or not */
+       char** excludeList;           /* List of files to not include */
+};
+typedef struct TarBallInfo TarBallInfo;
+
+
+/* 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 tempBuffer[32];
+       char *tempString = tempBuffer;
 
-       /* 
-        * Create the tar file for writing.
-        */
-       if ((tarName == NULL) || !strcmp(tarName, "-")) {
-               tostdoutFlag = TRUE;
-               tarFd = fileno(stdout);
-       } else
-               tarFd = open(tarName, O_WRONLY | O_CREAT | O_TRUNC, 0666);
+       /* Create a string of the specified length with an initial space,
+        * leading zeroes and the octal number, and a trailing null.  */
+       sprintf (tempString, "%0*lo", len - 1, value);
 
-       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;
+       /* If the string is too large, suppress the leading space.  */
+       tempLength = strlen (tempString) + 1;
+       if (tempLength > len) {
+               tempLength--;
+               tempString++;
        }
 
-       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);
-       }
+       /* If the string is still too large, suppress the trailing null.  */
+       if (tempLength > len)
+               tempLength--;
 
-       /* 
-        * Now write an empty block of zeroes to end the archive.
-        */
-       writeTarBlock("", 1);
+       /* If the string is still too large, fail.  */
+       if (tempLength > len)
+               return FALSE;
 
+       /* Copy the string to the field.  */
+       memcpy (cp, tempString, len);
 
-  done:
-       /* 
-        * Close the tar file and check for errors if it was opened.
-        */
-       if ((tostdoutFlag == FALSE) && (tarFd >= 0) && (close(tarFd) < 0))
-               perror(tarName);
+       return TRUE;
 }
 
-/*
- * 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)
+/* Write out a tar header for the specified file/directory/whatever */
+static int
+writeTarHeader(struct TarBallInfo *tbInfo, const char *fileName, struct stat *statbuf)
 {
-       int status;
-       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
+       long chksum=0;
+       struct TarHeader header;
+#if defined BB_FEATURE_TAR_EXCLUDE
+       char** tmpList;
 #endif
-               status = stat(fileName, &statbuf);
-
-       if (status < 0) {
-               perror(fileName);
+       const unsigned char *cp = (const unsigned char *) &header;
+       ssize_t size = sizeof(struct TarHeader);
 
-               return;
-       }
+       memset( &header, 0, size);
 
-       /* 
-        * 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;
+       if (*fileName=='/') {
+               static int alreadyWarned=FALSE;
+               if (alreadyWarned==FALSE) {
+                       errorMsg("tar: Removing leading '/' from member names\n");
+                       alreadyWarned=TRUE;
+               }
+               strncpy(header.name, fileName+1, sizeof(header.name)); 
        }
-
-       /* 
-        * Check the type of file.
-        */
-       mode = statbuf.st_mode;
-
-       if (S_ISDIR(mode)) {
-               saveDirectory(fileName, &statbuf);
-
-               return;
+       else {
+               strncpy(header.name, fileName, sizeof(header.name)); 
+       }
+
+#if defined BB_FEATURE_TAR_EXCLUDE
+       /* Check for excluded files....  */
+       for (tmpList=tbInfo->excludeList; tmpList && *tmpList; tmpList++) {
+               /* Do some extra hoop jumping for when directory names
+                * end in '/' but the entry in tmpList doesn't */
+               if (strncmp( *tmpList, header.name, strlen(*tmpList))==0 || (
+                                       header.name[strlen(header.name)-1]=='/'
+                                       && strncmp( *tmpList, header.name, 
+                                               MIN(strlen(header.name)-1, strlen(*tmpList)))==0)) {
+                       /* Set the mode to something that is not a regular file, thereby
+                        * faking out writeTarFile into thinking that nothing further need
+                        * be done for this file.  Yes, I know this is ugly, but it works. */
+                       statbuf->st_mode = 0;
+                       return( TRUE);
+               }
        }
-       if (S_ISREG(mode)) {
-               saveRegularFile(fileName, &statbuf);
+#endif
 
-               return;
+       putOctal(header.mode, sizeof(header.mode), statbuf->st_mode);
+       putOctal(header.uid, sizeof(header.uid), statbuf->st_uid);
+       putOctal(header.gid, sizeof(header.gid), statbuf->st_gid);
+       putOctal(header.size, sizeof(header.size), 0); /* Regular file size is handled later */
+       putOctal(header.mtime, sizeof(header.mtime), statbuf->st_mtime);
+       strncpy(header.magic, TAR_MAGIC TAR_VERSION, 
+                       TAR_MAGIC_LEN + TAR_VERSION_LEN );
+
+       /* Enter the user and group names (default to root if it fails) */
+       my_getpwuid(header.uname, statbuf->st_uid);
+       if (! *header.uname)
+               strcpy(header.uname, "root");
+       my_getgrgid(header.gname, statbuf->st_gid);
+       if (! *header.uname)
+               strcpy(header.uname, "root");
+
+       /* WARNING/NOTICE: I break Hard Links */
+       if (S_ISLNK(statbuf->st_mode)) {
+               char buffer[BUFSIZ];
+               header.typeflag  = SYMTYPE;
+               if ( readlink(fileName, buffer, sizeof(buffer) - 1) < 0) {
+                       errorMsg("Error reading symlink '%s': %s\n", header.name, strerror(errno));
+                       return ( FALSE);
+               }
+               strncpy(header.linkname, buffer, sizeof(header.linkname)); 
+       } else if (S_ISDIR(statbuf->st_mode)) {
+               header.typeflag  = DIRTYPE;
+               strncat(header.name, "/", sizeof(header.name)); 
+       } else if (S_ISCHR(statbuf->st_mode)) {
+               header.typeflag  = CHRTYPE;
+               putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev));
+               putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev));
+       } else if (S_ISBLK(statbuf->st_mode)) {
+               header.typeflag  = BLKTYPE;
+               putOctal(header.devmajor, sizeof(header.devmajor), MAJOR(statbuf->st_rdev));
+               putOctal(header.devminor, sizeof(header.devminor), MINOR(statbuf->st_rdev));
+       } else if (S_ISFIFO(statbuf->st_mode)) {
+               header.typeflag  = FIFOTYPE;
+       } else if (S_ISREG(statbuf->st_mode)) {
+               header.typeflag  = REGTYPE;
+               putOctal(header.size, sizeof(header.size), statbuf->st_size);
+       } else {
+               errorMsg("tar: %s: Unknown file type\n", fileName);
+               return ( FALSE);
        }
 
-       /* 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);
+       /* Calculate and store the checksum (i.e. the sum of all of the bytes of
+        * the header).  The checksum field must be filled with blanks for the
+        * calculation.  The checksum field is formatted differently from the
+        * other fields: it has [6] digits, a null, then a space -- rather than
+        * digits, followed by a null like the other fields... */
+       memset(header.chksum, ' ', sizeof(header.chksum));
+       cp = (const unsigned char *) &header;
+       while (size-- > 0)
+               chksum += *cp++;
+       putOctal(header.chksum, 7, chksum);
+       
+       /* Now write the header out to disk */
+       if ((size=fullWrite(tbInfo->tarFd, (char*)&header, sizeof(struct TarHeader))) < 0) {
+               errorMsg(io_error, fileName, strerror(errno)); 
+               return ( FALSE);
+       }
+       /* Pad the header up to the tar block size */
+       for (; size<TAR_BLOCK_SIZE; size++) {
+               write(tbInfo->tarFd, "\0", 1);
+       }
+       /* Now do the verbose thing (or not) */
+       if (tbInfo->verboseFlag==TRUE)
+               fprintf(stdout, "%s\n", header.name);
+
+       return ( TRUE);
 }
 
 
-/*
- * Save a regular file to the tar file.
- */
-static void
-saveRegularFile(const char *fileName, const struct stat *statbuf)
+static int writeFileToTarball(const char *fileName, struct stat *statbuf, void* userData)
 {
-       int sawEof;
-       int fileFd;
-       int cc;
-       int dataCount;
-       long fullDataCount;
-       char data[TAR_BLOCK_SIZE * 16];
+       struct TarBallInfo *tbInfo = (struct TarBallInfo *)userData;
 
-       /* 
-        * Open the file for reading.
-        */
-       fileFd = open(fileName, O_RDONLY);
-
-       if (fileFd < 0) {
-               perror(fileName);
-
-               return;
+       /* It is against the rules to archive a socket */
+       if (S_ISSOCK(statbuf->st_mode)) {
+               errorMsg("tar: %s: socket ignored\n", fileName);
+               return( TRUE);
        }
 
-       /* 
-        * 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);
+       /* It is a bad idea to store the archive we are in the process of creating,
+        * so check the device and inode to be sure that this particular file isn't
+        * the new tarball */
+       if (tbInfo->statBuf.st_dev == statbuf->st_dev &&
+                       tbInfo->statBuf.st_ino == statbuf->st_ino) {
+               errorMsg("tar: %s: file is the archive; skipping\n", fileName);
+               return( TRUE);
+       }
 
-                               (void) close(fileFd);
-                               errorFlag = TRUE;
+       if (writeTarHeader(tbInfo, fileName, statbuf)==FALSE) {
+               return( FALSE);
+       } 
 
-                               return;
-                       }
+       /* Now, if the file is a regular file, copy it out to the tarball */
+       if (S_ISREG(statbuf->st_mode)) {
+               int  inputFileFd;
+               char buffer[BUFSIZ];
+               ssize_t size=0, readSize=0;
 
-                       /* 
-                        * 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;
+               /* open the file we want to archive, and make sure all is well */
+               if ((inputFileFd = open(fileName, O_RDONLY)) < 0) {
+                       errorMsg("tar: %s: Cannot open: %s\n", fileName, strerror(errno));
+                       return( FALSE);
+               }
+               
+               /* write the file to the archive */
+               while ( (size = fullRead(inputFileFd, buffer, sizeof(buffer))) > 0 ) {
+                       if (fullWrite(tbInfo->tarFd, buffer, size) != size ) {
+                               /* Output file seems to have a problem */
+                               errorMsg(io_error, fileName, strerror(errno)); 
+                               return( FALSE);
                        }
+                       readSize+=size;
                }
-
-               /* 
-                * 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;
+               if (size == -1) {
+                       errorMsg(io_error, fileName, strerror(errno)); 
+                       return( FALSE);
+               }
+               /* Pad the file up to the tar block size */
+               for (; (readSize%TAR_BLOCK_SIZE) != 0; readSize++) {
+                       write(tbInfo->tarFd, "\0", 1);
+               }
+               close( inputFileFd);
        }
 
-       /* 
-        * Close the file.
-        */
-       if ((tostdoutFlag == FALSE) && close(fileFd) < 0)
-               fprintf(stderr, "%s: close: %s\n", fileName, strerror(errno));
+       return( TRUE);
 }
 
-
-/*
- * Save a directory and all of its files to the tar file.
- */
-static void saveDirectory(const char *dirName, const struct stat *statbuf)
+static int writeTarFile(const char* tarName, int tostdoutFlag, 
+               int verboseFlag, int argc, char **argv, char** excludeList)
 {
-       DIR *dir;
-       struct dirent *entry;
-       int needSlash;
-       char fullName[PATH_MAX + 1];
-
-       /* 
-        * Construct the directory name as used in the tar file by appending
-        * a slash character to it.
-        */
-       strcpy(fullName, dirName);
-       strcat(fullName, "/");
+       int tarFd=-1;
+       int errorFlag=FALSE;
+       ssize_t size;
+       struct TarBallInfo tbInfo;
+       tbInfo.verboseFlag = verboseFlag;
 
-       /* 
-        * Write out the header for the directory entry.
-        */
-       writeHeader(fullName, statbuf);
+       /* Make sure there is at least one file to tar up.  */
+       if (argc <= 0)
+               fatalError("tar: Cowardly refusing to create an empty archive\n");
 
-       /* 
-        * Open the directory.
-        */
-       dir = opendir(dirName);
-
-       if (dir == NULL) {
-               fprintf(stderr, "Cannot read directory \"%s\": %s\n",
-                               dirName, strerror(errno));
-
-               return;
+       /* Open the tar file for writing.  */
+       if (tostdoutFlag == TRUE)
+               tbInfo.tarFd = fileno(stdout);
+       else
+               tbInfo.tarFd = open (tarName, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+       if (tbInfo.tarFd < 0) {
+               errorMsg( "tar: Error opening '%s': %s\n", tarName, strerror(errno));
+               return ( FALSE);
        }
+       tbInfo.excludeList=excludeList;
+       /* Store the stat info for the tarball's file, so
+        * can avoid including the tarball into itself....  */
+       if (fstat(tbInfo.tarFd, &tbInfo.statBuf) < 0)
+               fatalError(io_error, tarName, strerror(errno)); 
 
-       /* 
-        * See if a slash is needed.
-        */
-       needSlash = (*dirName && (dirName[strlen(dirName) - 1] != '/'));
+       /* Set the umask for this process so it doesn't 
+        * screw up permission setting for us later. */
+       umask(0);
 
-       /* 
-        * 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;
+       /* Read the directory/files and iterate over them one at a time */
+       while (argc-- > 0) {
+               if (recursiveAction(*argv++, TRUE, FALSE, FALSE,
+                                       writeFileToTarball, writeFileToTarball, 
+                                       (void*) &tbInfo) == FALSE) {
+                       errorFlag = TRUE;
                }
-
-               /* 
-                * 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;
+       /* Write two empty blocks to the end of the archive */
+       for (size=0; size<(2*TAR_BLOCK_SIZE); size++) {
+               write(tbInfo.tarFd, "\0", 1);
        }
 
-       /* 
-        * 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);
+       /* To be pedantically correct, we would check if the tarball
+        * is smaller then 20 tar blocks, and pad it if it was smaller,
+        * but that isn't necessary for GNU tar interoperability, and
+        * so is considered a waste of space */
 
-               errorFlag = TRUE;
+       /* Hang up the tools, close up shop, head home */
+       close(tarFd);
+       if (errorFlag == TRUE) {
+               errorMsg("tar: Error exit delayed from previous errors\n");
+               return(FALSE);
        }
+       return( TRUE);
 }
 
 
-/*
- * 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;
-}
 #endif
 
-/* END CODE */