lib/filemode.c

   1 /* filemode.c -- make a string describing file modes
   2
   3    Copyright (C) 1985, 1990, 1993, 1998-2000, 2004, 2006, 2009-2012 Free
   4    Software Foundation, Inc.
   5
   6    This program is free software: you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include <config.h>
  20
  21 #include "filemode.h"
  22
  23 /* The following is for Cray DMF (Data Migration Facility), which is a
  24    HSM file system.  A migrated file has a 'st_dm_mode' that is
  25    different from the normal 'st_mode', so any tests for migrated
  26    files should use the former.  */
  27 #if HAVE_ST_DM_MODE
  28 # define IS_MIGRATED_FILE(statp) \
  29     (S_ISOFD (statp->st_dm_mode) || S_ISOFL (statp->st_dm_mode))
  30 #else
  31 # define IS_MIGRATED_FILE(statp) 0
  32 #endif
  33
  34 #if ! HAVE_DECL_STRMODE
  35
  36 /* Return a character indicating the type of file described by
  37    file mode BITS:
  38    '-' regular file
  39    'b' block special file
  40    'c' character special file
  41    'C' high performance ("contiguous data") file
  42    'd' directory
  43    'D' door
  44    'l' symbolic link
  45    'm' multiplexed file (7th edition Unix; obsolete)
  46    'n' network special file (HP-UX)
  47    'p' fifo (named pipe)
  48    'P' port
  49    's' socket
  50    'w' whiteout (4.4BSD)
  51    '?' some other file type  */
  52
  53 static char
  54 ftypelet (mode_t bits)
  55 {
  56   /* These are the most common, so test for them first.  */
  57   if (S_ISREG (bits))
  58     return '-';
  59   if (S_ISDIR (bits))
  60     return 'd';
  61
  62   /* Other letters standardized by POSIX 1003.1-2004.  */
  63   if (S_ISBLK (bits))
  64     return 'b';
  65   if (S_ISCHR (bits))
  66     return 'c';
  67   if (S_ISLNK (bits))
  68     return 'l';
  69   if (S_ISFIFO (bits))
  70     return 'p';
  71
  72   /* Other file types (though not letters) standardized by POSIX.  */
  73   if (S_ISSOCK (bits))
  74     return 's';
  75
  76   /* Nonstandard file types.  */
  77   if (S_ISCTG (bits))
  78     return 'C';
  79   if (S_ISDOOR (bits))
  80     return 'D';
  81   if (S_ISMPB (bits) || S_ISMPC (bits))
  82     return 'm';
  83   if (S_ISNWK (bits))
  84     return 'n';
  85   if (S_ISPORT (bits))
  86     return 'P';
  87   if (S_ISWHT (bits))
  88     return 'w';
  89
  90   return '?';
  91 }
  92
  93 /* Like filemodestring, but rely only on MODE.  */
  94
  95 void
  96 strmode (mode_t mode, char *str)
  97 {
  98   str[0] = ftypelet (mode);
  99   str[1] = mode & S_IRUSR ? 'r' : '-';
 100   str[2] = mode & S_IWUSR ? 'w' : '-';
 101   str[3] = (mode & S_ISUID
 102             ? (mode & S_IXUSR ? 's' : 'S')
 103             : (mode & S_IXUSR ? 'x' : '-'));
 104   str[4] = mode & S_IRGRP ? 'r' : '-';
 105   str[5] = mode & S_IWGRP ? 'w' : '-';
 106   str[6] = (mode & S_ISGID
 107             ? (mode & S_IXGRP ? 's' : 'S')
 108             : (mode & S_IXGRP ? 'x' : '-'));
 109   str[7] = mode & S_IROTH ? 'r' : '-';
 110   str[8] = mode & S_IWOTH ? 'w' : '-';
 111   str[9] = (mode & S_ISVTX
 112             ? (mode & S_IXOTH ? 't' : 'T')
 113             : (mode & S_IXOTH ? 'x' : '-'));
 114   str[10] = ' ';
 115   str[11] = '\0';
 116 }
 117
 118 #endif /* ! HAVE_DECL_STRMODE */
 119
 120 /* filemodestring - fill in string STR with an ls-style ASCII
 121    representation of the st_mode field of file stats block STATP.
 122    12 characters are stored in STR.
 123    The characters stored in STR are:
 124
 125    0    File type, as in ftypelet above, except that other letters are used
 126         for files whose type cannot be determined solely from st_mode:
 127
 128             'F' semaphore
 129             'M' migrated file (Cray DMF)
 130             'Q' message queue
 131             'S' shared memory object
 132             'T' typed memory object
 133
 134    1    'r' if the owner may read, '-' otherwise.
 135
 136    2    'w' if the owner may write, '-' otherwise.
 137
 138    3    'x' if the owner may execute, 's' if the file is
 139         set-user-id, '-' otherwise.
 140         'S' if the file is set-user-id, but the execute
 141         bit isn't set.
 142
 143    4    'r' if group members may read, '-' otherwise.
 144
 145    5    'w' if group members may write, '-' otherwise.
 146
 147    6    'x' if group members may execute, 's' if the file is
 148         set-group-id, '-' otherwise.
 149         'S' if it is set-group-id but not executable.
 150
 151    7    'r' if any user may read, '-' otherwise.
 152
 153    8    'w' if any user may write, '-' otherwise.
 154
 155    9    'x' if any user may execute, 't' if the file is "sticky"
 156         (will be retained in swap space after execution), '-'
 157         otherwise.
 158         'T' if the file is sticky but not executable.
 159
 160    10   ' ' for compatibility with 4.4BSD strmode,
 161         since this interface does not support ACLs.
 162
 163    11   '\0'.  */
 164
 165 void
 166 filemodestring (struct stat const *statp, char *str)
 167 {
 168   strmode (statp->st_mode, str);
 169
 170   if (S_TYPEISSEM (statp))
 171     str[0] = 'F';
 172   else if (IS_MIGRATED_FILE (statp))
 173     str[0] = 'M';
 174   else if (S_TYPEISMQ (statp))
 175     str[0] = 'Q';
 176   else if (S_TYPEISSHM (statp))
 177     str[0] = 'S';
 178   else if (S_TYPEISTMO (statp))
 179     str[0] = 'T';
 180 }