lib/decode.c

   1 /*
   2 **  Copyright 1998-2003 University of Illinois Board of Trustees
   3 **  Copyright 1998-2003 Mark D. Roth
   4 **  All rights reserved.
   5 **
   6 **  decode.c - libtar code to decode tar header blocks
   7 **
   8 **  Mark D. Roth <roth@uiuc.edu>
   9 **  Campus Information Technologies and Educational Services
  10 **  University of Illinois at Urbana-Champaign
  11 */
  12
  13 #include <internal.h>
  14
  15 #include <stdio.h>
  16 #include <sys/param.h>
  17 #include <pwd.h>
  18 #include <grp.h>
  19
  20 #ifdef STDC_HEADERS
  21 # include <string.h>
  22 #endif
  23
  24
  25 /* determine full path name */
  26 char *
  27 th_get_pathname(TAR *t)
  28 {
  29         if (t->th_buf.gnu_longname)
  30                 return t->th_buf.gnu_longname;
  31
  32         /* allocate the th_pathname buffer if not already */
  33         if (t->th_pathname == NULL)
  34         {
  35                 t->th_pathname = malloc(MAXPATHLEN * sizeof(char));
  36                 if (t->th_pathname == NULL)
  37                         /* out of memory */
  38                         return NULL;
  39         }
  40
  41         if (t->th_buf.prefix[0] == '\0')
  42         {
  43                 snprintf(t->th_pathname, MAXPATHLEN, "%.100s", t->th_buf.name);
  44         }
  45         else
  46         {
  47                 snprintf(t->th_pathname, MAXPATHLEN, "%.155s/%.100s",
  48                          t->th_buf.prefix, t->th_buf.name);
  49         }
  50
  51         /* will be deallocated in tar_close() */
  52         return t->th_pathname;
  53 }
  54
  55
  56 uid_t
  57 th_get_uid(TAR *t)
  58 {
  59         int uid;
  60         struct passwd *pw;
  61
  62         pw = getpwnam(t->th_buf.uname);
  63         if (pw != NULL)
  64                 return pw->pw_uid;
  65
  66         /* if the password entry doesn't exist */
  67         sscanf(t->th_buf.uid, "%o", &uid);
  68         return uid;
  69 }
  70
  71
  72 gid_t
  73 th_get_gid(TAR *t)
  74 {
  75         int gid;
  76         struct group *gr;
  77
  78         gr = getgrnam(t->th_buf.gname);
  79         if (gr != NULL)
  80                 return gr->gr_gid;
  81
  82         /* if the group entry doesn't exist */
  83         sscanf(t->th_buf.gid, "%o", &gid);
  84         return gid;
  85 }
  86
  87
  88 mode_t
  89 th_get_mode(TAR *t)
  90 {
  91         mode_t mode;
  92
  93         mode = (mode_t)oct_to_int(t->th_buf.mode);
  94         if (! (mode & S_IFMT))
  95         {
  96                 switch (t->th_buf.typeflag)
  97                 {
  98                 case SYMTYPE:
  99                         mode |= S_IFLNK;
 100                         break;
 101                 case CHRTYPE:
 102                         mode |= S_IFCHR;
 103                         break;
 104                 case BLKTYPE:
 105                         mode |= S_IFBLK;
 106                         break;
 107                 case DIRTYPE:
 108                         mode |= S_IFDIR;
 109                         break;
 110                 case FIFOTYPE:
 111                         mode |= S_IFIFO;
 112                         break;
 113                 case AREGTYPE:
 114                         if (t->th_buf.name[strlen(t->th_buf.name) - 1] == '/')
 115                         {
 116                                 mode |= S_IFDIR;
 117                                 break;
 118                         }
 119                         /* FALLTHROUGH */
 120                 case LNKTYPE:
 121                 case REGTYPE:
 122                 default:
 123                         mode |= S_IFREG;
 124                 }
 125         }
 126
 127         return mode;
 128 }
 129
 130