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      1 /*
      2  * untgz.c -- Display contents and extract files from a gzip'd TAR file
      3  *
      4  * written by Pedro A. Aranda Gutierrez <paag (at) tid.es>
      5  * adaptation to Unix by Jean-loup Gailly <jloup (at) gzip.org>
      6  * various fixes by Cosmin Truta <cosmint (at) cs.ubbcluj.ro>
      7  */
      8 
      9 #include <stdio.h>
     10 #include <stdlib.h>
     11 #include <string.h>
     12 #include <time.h>
     13 #include <errno.h>
     14 
     15 #include "zlib.h"
     16 
     17 #ifdef unix
     18 #  include <unistd.h>
     19 #else
     20 #  include <direct.h>
     21 #  include <io.h>
     22 #endif
     23 
     24 #ifdef WIN32
     25 #include <windows.h>
     26 #  ifndef F_OK
     27 #    define F_OK  0
     28 #  endif
     29 #  define mkdir(dirname,mode)   _mkdir(dirname)
     30 #  ifdef _MSC_VER
     31 #    define access(path,mode)   _access(path,mode)
     32 #    define chmod(path,mode)    _chmod(path,mode)
     33 #    define strdup(str)         _strdup(str)
     34 #  endif
     35 #else
     36 #  include <utime.h>
     37 #endif
     38 
     39 
     40 /* values used in typeflag field */
     41 
     42 #define REGTYPE  '0'            /* regular file */
     43 #define AREGTYPE '\0'           /* regular file */
     44 #define LNKTYPE  '1'            /* link */
     45 #define SYMTYPE  '2'            /* reserved */
     46 #define CHRTYPE  '3'            /* character special */
     47 #define BLKTYPE  '4'            /* block special */
     48 #define DIRTYPE  '5'            /* directory */
     49 #define FIFOTYPE '6'            /* FIFO special */
     50 #define CONTTYPE '7'            /* reserved */
     51 
     52 /* GNU tar extensions */
     53 
     54 #define GNUTYPE_DUMPDIR  'D'    /* file names from dumped directory */
     55 #define GNUTYPE_LONGLINK 'K'    /* long link name */
     56 #define GNUTYPE_LONGNAME 'L'    /* long file name */
     57 #define GNUTYPE_MULTIVOL 'M'    /* continuation of file from another volume */
     58 #define GNUTYPE_NAMES    'N'    /* file name that does not fit into main hdr */
     59 #define GNUTYPE_SPARSE   'S'    /* sparse file */
     60 #define GNUTYPE_VOLHDR   'V'    /* tape/volume header */
     61 
     62 
     63 /* tar header */
     64 
     65 #define BLOCKSIZE     512
     66 #define SHORTNAMESIZE 100
     67 
     68 struct tar_header
     69 {                               /* byte offset */
     70   char name[100];               /*   0 */
     71   char mode[8];                 /* 100 */
     72   char uid[8];                  /* 108 */
     73   char gid[8];                  /* 116 */
     74   char size[12];                /* 124 */
     75   char mtime[12];               /* 136 */
     76   char chksum[8];               /* 148 */
     77   char typeflag;                /* 156 */
     78   char linkname[100];           /* 157 */
     79   char magic[6];                /* 257 */
     80   char version[2];              /* 263 */
     81   char uname[32];               /* 265 */
     82   char gname[32];               /* 297 */
     83   char devmajor[8];             /* 329 */
     84   char devminor[8];             /* 337 */
     85   char prefix[155];             /* 345 */
     86                                 /* 500 */
     87 };
     88 
     89 union tar_buffer
     90 {
     91   char               buffer[BLOCKSIZE];
     92   struct tar_header  header;
     93 };
     94 
     95 struct attr_item
     96 {
     97   struct attr_item  *next;
     98   char              *fname;
     99   int                mode;
    100   time_t             time;
    101 };
    102 
    103 enum { TGZ_EXTRACT, TGZ_LIST, TGZ_INVALID };
    104 
    105 char *TGZfname          OF((const char *));
    106 void TGZnotfound        OF((const char *));
    107 
    108 int getoct              OF((char *, int));
    109 char *strtime           OF((time_t *));
    110 int setfiletime         OF((char *, time_t));
    111 void push_attr          OF((struct attr_item **, char *, int, time_t));
    112 void restore_attr       OF((struct attr_item **));
    113 
    114 int ExprMatch           OF((char *, char *));
    115 
    116 int makedir             OF((char *));
    117 int matchname           OF((int, int, char **, char *));
    118 
    119 void error              OF((const char *));
    120 int tar                 OF((gzFile, int, int, int, char **));
    121 
    122 void help               OF((int));
    123 int main                OF((int, char **));
    124 
    125 char *prog;
    126 
    127 const char *TGZsuffix[] = { "\0", ".tar", ".tar.gz", ".taz", ".tgz", NULL };
    128 
    129 /* return the file name of the TGZ archive */
    130 /* or NULL if it does not exist */
    131 
    132 char *TGZfname (const char *arcname)
    133 {
    134   static char buffer[1024];
    135   int origlen,i;
    136 
    137   strcpy(buffer,arcname);
    138   origlen = strlen(buffer);
    139 
    140   for (i=0; TGZsuffix[i]; i++)
    141     {
    142        strcpy(buffer+origlen,TGZsuffix[i]);
    143        if (access(buffer,F_OK) == 0)
    144          return buffer;
    145     }
    146   return NULL;
    147 }
    148 
    149 
    150 /* error message for the filename */
    151 
    152 void TGZnotfound (const char *arcname)
    153 {
    154   int i;
    155 
    156   fprintf(stderr,"%s: Couldn't find ",prog);
    157   for (i=0;TGZsuffix[i];i++)
    158     fprintf(stderr,(TGZsuffix[i+1]) ? "%s%s, " : "or %s%s\n",
    159             arcname,
    160             TGZsuffix[i]);
    161   exit(1);
    162 }
    163 
    164 
    165 /* convert octal digits to int */
    166 /* on error return -1 */
    167 
    168 int getoct (char *p,int width)
    169 {
    170   int result = 0;
    171   char c;
    172 
    173   while (width--)
    174     {
    175       c = *p++;
    176       if (c == 0)
    177         break;
    178       if (c == ' ')
    179         continue;
    180       if (c < '0' || c > '7')
    181         return -1;
    182       result = result * 8 + (c - '0');
    183     }
    184   return result;
    185 }
    186 
    187 
    188 /* convert time_t to string */
    189 /* use the "YYYY/MM/DD hh:mm:ss" format */
    190 
    191 char *strtime (time_t *t)
    192 {
    193   struct tm   *local;
    194   static char result[32];
    195 
    196   local = localtime(t);
    197   sprintf(result,"%4d/%02d/%02d %02d:%02d:%02d",
    198           local->tm_year+1900, local->tm_mon+1, local->tm_mday,
    199           local->tm_hour, local->tm_min, local->tm_sec);
    200   return result;
    201 }
    202 
    203 
    204 /* set file time */
    205 
    206 int setfiletime (char *fname,time_t ftime)
    207 {
    208 #ifdef WIN32
    209   static int isWinNT = -1;
    210   SYSTEMTIME st;
    211   FILETIME locft, modft;
    212   struct tm *loctm;
    213   HANDLE hFile;
    214   int result;
    215 
    216   loctm = localtime(&ftime);
    217   if (loctm == NULL)
    218     return -1;
    219 
    220   st.wYear         = (WORD)loctm->tm_year + 1900;
    221   st.wMonth        = (WORD)loctm->tm_mon + 1;
    222   st.wDayOfWeek    = (WORD)loctm->tm_wday;
    223   st.wDay          = (WORD)loctm->tm_mday;
    224   st.wHour         = (WORD)loctm->tm_hour;
    225   st.wMinute       = (WORD)loctm->tm_min;
    226   st.wSecond       = (WORD)loctm->tm_sec;
    227   st.wMilliseconds = 0;
    228   if (!SystemTimeToFileTime(&st, &locft) ||
    229       !LocalFileTimeToFileTime(&locft, &modft))
    230     return -1;
    231 
    232   if (isWinNT < 0)
    233     isWinNT = (GetVersion() < 0x80000000) ? 1 : 0;
    234   hFile = CreateFile(fname, GENERIC_WRITE, 0, NULL, OPEN_EXISTING,
    235                      (isWinNT ? FILE_FLAG_BACKUP_SEMANTICS : 0),
    236                      NULL);
    237   if (hFile == INVALID_HANDLE_VALUE)
    238     return -1;
    239   result = SetFileTime(hFile, NULL, NULL, &modft) ? 0 : -1;
    240   CloseHandle(hFile);
    241   return result;
    242 #else
    243   struct utimbuf settime;
    244 
    245   settime.actime = settime.modtime = ftime;
    246   return utime(fname,&settime);
    247 #endif
    248 }
    249 
    250 
    251 /* push file attributes */
    252 
    253 void push_attr(struct attr_item **list,char *fname,int mode,time_t time)
    254 {
    255   struct attr_item *item;
    256 
    257   item = (struct attr_item *)malloc(sizeof(struct attr_item));
    258   if (item == NULL)
    259     error("Out of memory");
    260   item->fname = strdup(fname);
    261   item->mode  = mode;
    262   item->time  = time;
    263   item->next  = *list;
    264   *list       = item;
    265 }
    266 
    267 
    268 /* restore file attributes */
    269 
    270 void restore_attr(struct attr_item **list)
    271 {
    272   struct attr_item *item, *prev;
    273 
    274   for (item = *list; item != NULL; )
    275     {
    276       setfiletime(item->fname,item->time);
    277       chmod(item->fname,item->mode);
    278       prev = item;
    279       item = item->next;
    280       free(prev);
    281     }
    282   *list = NULL;
    283 }
    284 
    285 
    286 /* match regular expression */
    287 
    288 #define ISSPECIAL(c) (((c) == '*') || ((c) == '/'))
    289 
    290 int ExprMatch (char *string,char *expr)
    291 {
    292   while (1)
    293     {
    294       if (ISSPECIAL(*expr))
    295         {
    296           if (*expr == '/')
    297             {
    298               if (*string != '\\' && *string != '/')
    299                 return 0;
    300               string ++; expr++;
    301             }
    302           else if (*expr == '*')
    303             {
    304               if (*expr ++ == 0)
    305                 return 1;
    306               while (*++string != *expr)
    307                 if (*string == 0)
    308                   return 0;
    309             }
    310         }
    311       else
    312         {
    313           if (*string != *expr)
    314             return 0;
    315           if (*expr++ == 0)
    316             return 1;
    317           string++;
    318         }
    319     }
    320 }
    321 
    322 
    323 /* recursive mkdir */
    324 /* abort on ENOENT; ignore other errors like "directory already exists" */
    325 /* return 1 if OK */
    326 /*        0 on error */
    327 
    328 int makedir (char *newdir)
    329 {
    330   char *buffer = strdup(newdir);
    331   char *p;
    332   int  len = strlen(buffer);
    333 
    334   if (len <= 0) {
    335     free(buffer);
    336     return 0;
    337   }
    338   if (buffer[len-1] == '/') {
    339     buffer[len-1] = '\0';
    340   }
    341   if (mkdir(buffer, 0755) == 0)
    342     {
    343       free(buffer);
    344       return 1;
    345     }
    346 
    347   p = buffer+1;
    348   while (1)
    349     {
    350       char hold;
    351 
    352       while(*p && *p != '\\' && *p != '/')
    353         p++;
    354       hold = *p;
    355       *p = 0;
    356       if ((mkdir(buffer, 0755) == -1) && (errno == ENOENT))
    357         {
    358           fprintf(stderr,"%s: Couldn't create directory %s\n",prog,buffer);
    359           free(buffer);
    360           return 0;
    361         }
    362       if (hold == 0)
    363         break;
    364       *p++ = hold;
    365     }
    366   free(buffer);
    367   return 1;
    368 }
    369 
    370 
    371 int matchname (int arg,int argc,char **argv,char *fname)
    372 {
    373   if (arg == argc)      /* no arguments given (untgz tgzarchive) */
    374     return 1;
    375 
    376   while (arg < argc)
    377     if (ExprMatch(fname,argv[arg++]))
    378       return 1;
    379 
    380   return 0; /* ignore this for the moment being */
    381 }
    382 
    383 
    384 /* tar file list or extract */
    385 
    386 int tar (gzFile in,int action,int arg,int argc,char **argv)
    387 {
    388   union  tar_buffer buffer;
    389   int    len;
    390   int    err;
    391   int    getheader = 1;
    392   int    remaining = 0;
    393   FILE   *outfile = NULL;
    394   char   fname[BLOCKSIZE];
    395   int    tarmode;
    396   time_t tartime;
    397   struct attr_item *attributes = NULL;
    398 
    399   if (action == TGZ_LIST)
    400     printf("    date      time     size                       file\n"
    401            " ---------- -------- --------- -------------------------------------\n");
    402   while (1)
    403     {
    404       len = gzread(in, &buffer, BLOCKSIZE);
    405       if (len < 0)
    406         error(gzerror(in, &err));
    407       /*
    408        * Always expect complete blocks to process
    409        * the tar information.
    410        */
    411       if (len != BLOCKSIZE)
    412         {
    413           action = TGZ_INVALID; /* force error exit */
    414           remaining = 0;        /* force I/O cleanup */
    415         }
    416 
    417       /*
    418        * If we have to get a tar header
    419        */
    420       if (getheader >= 1)
    421         {
    422           /*
    423            * if we met the end of the tar
    424            * or the end-of-tar block,
    425            * we are done
    426            */
    427           if (len == 0 || buffer.header.name[0] == 0)
    428             break;
    429 
    430           tarmode = getoct(buffer.header.mode,8);
    431           tartime = (time_t)getoct(buffer.header.mtime,12);
    432           if (tarmode == -1 || tartime == (time_t)-1)
    433             {
    434               buffer.header.name[0] = 0;
    435               action = TGZ_INVALID;
    436             }
    437 
    438           if (getheader == 1)
    439             {
    440               strncpy(fname,buffer.header.name,SHORTNAMESIZE);
    441               if (fname[SHORTNAMESIZE-1] != 0)
    442                   fname[SHORTNAMESIZE] = 0;
    443             }
    444           else
    445             {
    446               /*
    447                * The file name is longer than SHORTNAMESIZE
    448                */
    449               if (strncmp(fname,buffer.header.name,SHORTNAMESIZE-1) != 0)
    450                   error("bad long name");
    451               getheader = 1;
    452             }
    453 
    454           /*
    455            * Act according to the type flag
    456            */
    457           switch (buffer.header.typeflag)
    458             {
    459             case DIRTYPE:
    460               if (action == TGZ_LIST)
    461                 printf(" %s     <dir> %s\n",strtime(&tartime),fname);
    462               if (action == TGZ_EXTRACT)
    463                 {
    464                   makedir(fname);
    465                   push_attr(&attributes,fname,tarmode,tartime);
    466                 }
    467               break;
    468             case REGTYPE:
    469             case AREGTYPE:
    470               remaining = getoct(buffer.header.size,12);
    471               if (remaining == -1)
    472                 {
    473                   action = TGZ_INVALID;
    474                   break;
    475                 }
    476               if (action == TGZ_LIST)
    477                 printf(" %s %9d %s\n",strtime(&tartime),remaining,fname);
    478               else if (action == TGZ_EXTRACT)
    479                 {
    480                   if (matchname(arg,argc,argv,fname))
    481                     {
    482                       outfile = fopen(fname,"wb");
    483                       if (outfile == NULL) {
    484                         /* try creating directory */
    485                         char *p = strrchr(fname, '/');
    486                         if (p != NULL) {
    487                           *p = '\0';
    488                           makedir(fname);
    489                           *p = '/';
    490                           outfile = fopen(fname,"wb");
    491                         }
    492                       }
    493                       if (outfile != NULL)
    494                         printf("Extracting %s\n",fname);
    495                       else
    496                         fprintf(stderr, "%s: Couldn't create %s",prog,fname);
    497                     }
    498                   else
    499                     outfile = NULL;
    500                 }
    501               getheader = 0;
    502               break;
    503             case GNUTYPE_LONGLINK:
    504             case GNUTYPE_LONGNAME:
    505               remaining = getoct(buffer.header.size,12);
    506               if (remaining < 0 || remaining >= BLOCKSIZE)
    507                 {
    508                   action = TGZ_INVALID;
    509                   break;
    510                 }
    511               len = gzread(in, fname, BLOCKSIZE);
    512               if (len < 0)
    513                 error(gzerror(in, &err));
    514               if (fname[BLOCKSIZE-1] != 0 || (int)strlen(fname) > remaining)
    515                 {
    516                   action = TGZ_INVALID;
    517                   break;
    518                 }
    519               getheader = 2;
    520               break;
    521             default:
    522               if (action == TGZ_LIST)
    523                 printf(" %s     <---> %s\n",strtime(&tartime),fname);
    524               break;
    525             }
    526         }
    527       else
    528         {
    529           unsigned int bytes = (remaining > BLOCKSIZE) ? BLOCKSIZE : remaining;
    530 
    531           if (outfile != NULL)
    532             {
    533               if (fwrite(&buffer,sizeof(char),bytes,outfile) != bytes)
    534                 {
    535                   fprintf(stderr,
    536                     "%s: Error writing %s -- skipping\n",prog,fname);
    537                   fclose(outfile);
    538                   outfile = NULL;
    539                   remove(fname);
    540                 }
    541             }
    542           remaining -= bytes;
    543         }
    544 
    545       if (remaining == 0)
    546         {
    547           getheader = 1;
    548           if (outfile != NULL)
    549             {
    550               fclose(outfile);
    551               outfile = NULL;
    552               if (action != TGZ_INVALID)
    553                 push_attr(&attributes,fname,tarmode,tartime);
    554             }
    555         }
    556 
    557       /*
    558        * Abandon if errors are found
    559        */
    560       if (action == TGZ_INVALID)
    561         {
    562           error("broken archive");
    563           break;
    564         }
    565     }
    566 
    567   /*
    568    * Restore file modes and time stamps
    569    */
    570   restore_attr(&attributes);
    571 
    572   if (gzclose(in) != Z_OK)
    573     error("failed gzclose");
    574 
    575   return 0;
    576 }
    577 
    578 
    579 /* ============================================================ */
    580 
    581 void help(int exitval)
    582 {
    583   printf("untgz version 0.2.1\n"
    584          "  using zlib version %s\n\n",
    585          zlibVersion());
    586   printf("Usage: untgz file.tgz            extract all files\n"
    587          "       untgz file.tgz fname ...  extract selected files\n"
    588          "       untgz -l file.tgz         list archive contents\n"
    589          "       untgz -h                  display this help\n");
    590   exit(exitval);
    591 }
    592 
    593 void error(const char *msg)
    594 {
    595   fprintf(stderr, "%s: %s\n", prog, msg);
    596   exit(1);
    597 }
    598 
    599 
    600 /* ============================================================ */
    601 
    602 #if defined(WIN32) && defined(__GNUC__)
    603 int _CRT_glob = 0;      /* disable argument globbing in MinGW */
    604 #endif
    605 
    606 int main(int argc,char **argv)
    607 {
    608     int         action = TGZ_EXTRACT;
    609     int         arg = 1;
    610     char        *TGZfile;
    611     gzFile      *f;
    612 
    613     prog = strrchr(argv[0],'\\');
    614     if (prog == NULL)
    615       {
    616         prog = strrchr(argv[0],'/');
    617         if (prog == NULL)
    618           {
    619             prog = strrchr(argv[0],':');
    620             if (prog == NULL)
    621               prog = argv[0];
    622             else
    623               prog++;
    624           }
    625         else
    626           prog++;
    627       }
    628     else
    629       prog++;
    630 
    631     if (argc == 1)
    632       help(0);
    633 
    634     if (strcmp(argv[arg],"-l") == 0)
    635       {
    636         action = TGZ_LIST;
    637         if (argc == ++arg)
    638           help(0);
    639       }
    640     else if (strcmp(argv[arg],"-h") == 0)
    641       {
    642         help(0);
    643       }
    644 
    645     if ((TGZfile = TGZfname(argv[arg])) == NULL)
    646       TGZnotfound(argv[arg]);
    647 
    648     ++arg;
    649     if ((action == TGZ_LIST) && (arg != argc))
    650       help(1);
    651 
    652 /*
    653  *  Process the TGZ file
    654  */
    655     switch(action)
    656       {
    657       case TGZ_LIST:
    658       case TGZ_EXTRACT:
    659         f = gzopen(TGZfile,"rb");
    660         if (f == NULL)
    661           {
    662             fprintf(stderr,"%s: Couldn't gzopen %s\n",prog,TGZfile);
    663             return 1;
    664           }
    665         exit(tar(f, action, arg, argc, argv));
    666       break;
    667 
    668       default:
    669         error("Unknown option");
    670         exit(1);
    671       }
    672 
    673     return 0;
    674 }
    675