lib/filemode.c

   1 /* filemode.c -- make a string describing file modes
   2    Copyright (C) 1985, 1990, 1993 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software
  16    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  17 \f
  18 #ifdef HAVE_CONFIG_H
  19 #include <config.h>
  20 #endif
  21
  22 #include <sys/types.h>
  23 #include <sys/stat.h>
  24
  25 #ifndef S_IREAD
  26 #define S_IREAD S_IRUSR
  27 #define S_IWRITE S_IWUSR
  28 #define S_IEXEC S_IXUSR
  29 #endif
  30
  31 #ifdef STAT_MACROS_BROKEN
  32 #undef S_ISBLK
  33 #undef S_ISCHR
  34 #undef S_ISDIR
  35 #undef S_ISFIFO
  36 #undef S_ISLNK
  37 #undef S_ISMPB
  38 #undef S_ISMPC
  39 #undef S_ISNWK
  40 #undef S_ISREG
  41 #undef S_ISSOCK
  42 #endif /* STAT_MACROS_BROKEN.  */
  43
  44 #if !defined(S_ISBLK) && defined(S_IFBLK)
  45 #define S_ISBLK(m) (((m) & S_IFMT) == S_IFBLK)
  46 #endif
  47 #if !defined(S_ISCHR) && defined(S_IFCHR)
  48 #define S_ISCHR(m) (((m) & S_IFMT) == S_IFCHR)
  49 #endif
  50 #if !defined(S_ISDIR) && defined(S_IFDIR)
  51 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
  52 #endif
  53 #if !defined(S_ISREG) && defined(S_IFREG)
  54 #define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
  55 #endif
  56 #if !defined(S_ISFIFO) && defined(S_IFIFO)
  57 #define S_ISFIFO(m) (((m) & S_IFMT) == S_IFIFO)
  58 #endif
  59 #if !defined(S_ISLNK) && defined(S_IFLNK)
  60 #define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
  61 #endif
  62 #if !defined(S_ISSOCK) && defined(S_IFSOCK)
  63 #define S_ISSOCK(m) (((m) & S_IFMT) == S_IFSOCK)
  64 #endif
  65 #if !defined(S_ISMPB) && defined(S_IFMPB) /* V7 */
  66 #define S_ISMPB(m) (((m) & S_IFMT) == S_IFMPB)
  67 #define S_ISMPC(m) (((m) & S_IFMT) == S_IFMPC)
  68 #endif
  69 #if !defined(S_ISNWK) && defined(S_IFNWK) /* HP/UX */
  70 #define S_ISNWK(m) (((m) & S_IFMT) == S_IFNWK)
  71 #endif
  72
  73 void mode_string ();
  74 static char ftypelet ();
  75 static void rwx ();
  76 static void setst ();
  77
  78 /* filemodestring - fill in string STR with an ls-style ASCII
  79    representation of the st_mode field of file stats block STATP.
  80    10 characters are stored in STR; no terminating null is added.
  81    The characters stored in STR are:
  82
  83    0    File type.  'd' for directory, 'c' for character
  84         special, 'b' for block special, 'm' for multiplex,
  85         'l' for symbolic link, 's' for socket, 'p' for fifo,
  86         '-' for regular, '?' for any other file type
  87
  88    1    'r' if the owner may read, '-' otherwise.
  89
  90    2    'w' if the owner may write, '-' otherwise.
  91
  92    3    'x' if the owner may execute, 's' if the file is
  93         set-user-id, '-' otherwise.
  94         'S' if the file is set-user-id, but the execute
  95         bit isn't set.
  96
  97    4    'r' if group members may read, '-' otherwise.
  98
  99    5    'w' if group members may write, '-' otherwise.
 100
 101    6    'x' if group members may execute, 's' if the file is
 102         set-group-id, '-' otherwise.
 103         'S' if it is set-group-id but not executable.
 104
 105    7    'r' if any user may read, '-' otherwise.
 106
 107    8    'w' if any user may write, '-' otherwise.
 108
 109    9    'x' if any user may execute, 't' if the file is "sticky"
 110         (will be retained in swap space after execution), '-'
 111         otherwise.
 112         'T' if the file is sticky but not executable.  */
 113
 114 void
 115 filemodestring (statp, str)
 116      struct stat *statp;
 117      char *str;
 118 {
 119   mode_string (statp->st_mode, str);
 120 }
 121
 122 /* Like filemodestring, but only the relevant part of the `struct stat'
 123    is given as an argument.  */
 124
 125 void
 126 mode_string (mode, str)
 127      unsigned short mode;
 128      char *str;
 129 {
 130   str[0] = ftypelet ((long) mode);
 131   rwx ((mode & 0700) << 0, &str[1]);
 132   rwx ((mode & 0070) << 3, &str[4]);
 133   rwx ((mode & 0007) << 6, &str[7]);
 134   setst (mode, str);
 135 }
 136
 137 /* Return a character indicating the type of file described by
 138    file mode BITS:
 139    'd' for directories
 140    'b' for block special files
 141    'c' for character special files
 142    'm' for multiplexor files
 143    'l' for symbolic links
 144    's' for sockets
 145    'p' for fifos
 146    '-' for regular files
 147    '?' for any other file type.  */
 148
 149 static char
 150 ftypelet (bits)
 151      long bits;
 152 {
 153 #ifdef S_ISBLK
 154   if (S_ISBLK (bits))
 155     return 'b';
 156 #endif
 157   if (S_ISCHR (bits))
 158     return 'c';
 159   if (S_ISDIR (bits))
 160     return 'd';
 161   if (S_ISREG (bits))
 162     return '-';
 163 #ifdef S_ISFIFO
 164   if (S_ISFIFO (bits))
 165     return 'p';
 166 #endif
 167 #ifdef S_ISLNK
 168   if (S_ISLNK (bits))
 169     return 'l';
 170 #endif
 171 #ifdef S_ISSOCK
 172   if (S_ISSOCK (bits))
 173     return 's';
 174 #endif
 175 #ifdef S_ISMPC
 176   if (S_ISMPC (bits))
 177     return 'm';
 178 #endif
 179 #ifdef S_ISNWK
 180   if (S_ISNWK (bits))
 181     return 'n';
 182 #endif
 183   return '?';
 184 }
 185
 186 /* Look at read, write, and execute bits in BITS and set
 187    flags in CHARS accordingly.  */
 188
 189 static void
 190 rwx (bits, chars)
 191      unsigned short bits;
 192      char *chars;
 193 {
 194   chars[0] = (bits & S_IREAD) ? 'r' : '-';
 195   chars[1] = (bits & S_IWRITE) ? 'w' : '-';
 196   chars[2] = (bits & S_IEXEC) ? 'x' : '-';
 197 }
 198
 199 /* Set the 's' and 't' flags in file attributes string CHARS,
 200    according to the file mode BITS.  */
 201
 202 static void
 203 setst (bits, chars)
 204      unsigned short bits;
 205      char *chars;
 206 {
 207 #ifdef S_ISUID
 208   if (bits & S_ISUID)
 209     {
 210       if (chars[3] != 'x')
 211         /* Set-uid, but not executable by owner.  */
 212         chars[3] = 'S';
 213       else
 214         chars[3] = 's';
 215     }
 216 #endif
 217 #ifdef S_ISGID
 218   if (bits & S_ISGID)
 219     {
 220       if (chars[6] != 'x')
 221         /* Set-gid, but not executable by group.  */
 222         chars[6] = 'S';
 223       else
 224         chars[6] = 's';
 225     }
 226 #endif
 227 #ifdef S_ISVTX
 228   if (bits & S_ISVTX)
 229     {
 230       if (chars[9] != 'x')
 231         /* Sticky, but not executable by others.  */
 232         chars[9] = 'T';
 233       else
 234         chars[9] = 't';
 235     }
 236 #endif
 237 }