src/filemode.c

   1 /* filemode.c -- make a string describing file modes
   2    Copyright (C) 1985, 1990, 1993, 2001-2011  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 3, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  17    USA.  */
  18 \f
  19 #include <config.h>
  20 #include <sys/types.h>
  21 #include <sys/stat.h>
  22
  23 #if !S_IRUSR
  24 # if S_IREAD
  25 #  define S_IRUSR S_IREAD
  26 # else
  27 #  define S_IRUSR 00400
  28 # endif
  29 #endif
  30
  31 #if !S_IWUSR
  32 # if S_IWRITE
  33 #  define S_IWUSR S_IWRITE
  34 # else
  35 #  define S_IWUSR 00200
  36 # endif
  37 #endif
  38
  39 #if !S_IXUSR
  40 # if S_IEXEC
  41 #  define S_IXUSR S_IEXEC
  42 # else
  43 #  define S_IXUSR 00100
  44 # endif
  45 #endif
  46
  47 #ifdef STAT_MACROS_BROKEN
  48 #undef S_ISBLK
  49 #undef S_ISCHR
  50 #undef S_ISDIR
  51 #undef S_ISFIFO
  52 #undef S_ISLNK
  53 #undef S_ISMPB
  54 #undef S_ISMPC
  55 #undef S_ISNWK
  56 #undef S_ISREG
  57 #undef S_ISSOCK
  58 #endif /* STAT_MACROS_BROKEN.  */
  59
  60 #if !defined(S_ISBLK) && defined(S_IFBLK)
  61 #define S_ISBLK(m) (((m) & S_IFMT) == S_IFBLK)
  62 #endif
  63 #if !defined(S_ISCHR) && defined(S_IFCHR)
  64 #define S_ISCHR(m) (((m) & S_IFMT) == S_IFCHR)
  65 #endif
  66 #if !defined(S_ISDIR) && defined(S_IFDIR)
  67 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
  68 #endif
  69 #if !defined(S_ISREG) && defined(S_IFREG)
  70 #define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
  71 #endif
  72 #if !defined(S_ISFIFO) && defined(S_IFIFO)
  73 #define S_ISFIFO(m) (((m) & S_IFMT) == S_IFIFO)
  74 #endif
  75 #if !defined(S_ISLNK) && defined(S_IFLNK)
  76 #define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
  77 #endif
  78 #if !defined(S_ISSOCK) && defined(S_IFSOCK)
  79 #define S_ISSOCK(m) (((m) & S_IFMT) == S_IFSOCK)
  80 #endif
  81 #if !defined(S_ISMPB) && defined(S_IFMPB) /* V7 */
  82 #define S_ISMPB(m) (((m) & S_IFMT) == S_IFMPB)
  83 #define S_ISMPC(m) (((m) & S_IFMT) == S_IFMPC)
  84 #endif
  85 #if !defined(S_ISNWK) && defined(S_IFNWK) /* HP/UX */
  86 #define S_ISNWK(m) (((m) & S_IFMT) == S_IFNWK)
  87 #endif
  88
  89 void mode_string (short unsigned int mode, char *str);
  90 static char ftypelet (long int bits);
  91 static void rwx (short unsigned int bits, char *chars);
  92 static void setst (short unsigned int bits, char *chars);
  93
  94 /* filemodestring - fill in string STR with an ls-style ASCII
  95    representation of the st_mode field of file stats block STATP.
  96    10 characters are stored in STR; no terminating null is added.
  97    The characters stored in STR are:
  98
  99    0    File type.  'd' for directory, 'c' for character
 100         special, 'b' for block special, 'm' for multiplex,
 101         'l' for symbolic link, 's' for socket, 'p' for fifo,
 102         '-' for regular, '?' for any other file type
 103
 104    1    'r' if the owner may read, '-' otherwise.
 105
 106    2    'w' if the owner may write, '-' otherwise.
 107
 108    3    'x' if the owner may execute, 's' if the file is
 109         set-user-id, '-' otherwise.
 110         'S' if the file is set-user-id, but the execute
 111         bit isn't set.
 112
 113    4    'r' if group members may read, '-' otherwise.
 114
 115    5    'w' if group members may write, '-' otherwise.
 116
 117    6    'x' if group members may execute, 's' if the file is
 118         set-group-id, '-' otherwise.
 119         'S' if it is set-group-id but not executable.
 120
 121    7    'r' if any user may read, '-' otherwise.
 122
 123    8    'w' if any user may write, '-' otherwise.
 124
 125    9    'x' if any user may execute, 't' if the file is "sticky"
 126         (will be retained in swap space after execution), '-'
 127         otherwise.
 128         'T' if the file is sticky but not executable.  */
 129
 130 void
 131 filemodestring (struct stat *statp, char *str)
 132 {
 133   mode_string (statp->st_mode, str);
 134 }
 135
 136 /* Like filemodestring, but only the relevant part of the `struct stat'
 137    is given as an argument.  */
 138
 139 void
 140 mode_string (short unsigned int mode, char *str)
 141 {
 142   str[0] = ftypelet ((long) mode);
 143   rwx ((mode & 0700) << 0, &str[1]);
 144   rwx ((mode & 0070) << 3, &str[4]);
 145   rwx ((mode & 0007) << 6, &str[7]);
 146   setst (mode, str);
 147 }
 148
 149 /* Return a character indicating the type of file described by
 150    file mode BITS:
 151    'd' for directories
 152    'b' for block special files
 153    'c' for character special files
 154    'm' for multiplexor files
 155    'l' for symbolic links
 156    's' for sockets
 157    'p' for fifos
 158    '-' for regular files
 159    '?' for any other file type.  */
 160
 161 static char
 162 ftypelet (long int bits)
 163 {
 164 #ifdef S_ISBLK
 165   if (S_ISBLK (bits))
 166     return 'b';
 167 #endif
 168   if (S_ISCHR (bits))
 169     return 'c';
 170   if (S_ISDIR (bits))
 171     return 'd';
 172   if (S_ISREG (bits))
 173     return '-';
 174 #ifdef S_ISFIFO
 175   if (S_ISFIFO (bits))
 176     return 'p';
 177 #endif
 178 #ifdef S_ISLNK
 179   if (S_ISLNK (bits))
 180     return 'l';
 181 #endif
 182 #ifdef S_ISSOCK
 183   if (S_ISSOCK (bits))
 184     return 's';
 185 #endif
 186 #ifdef S_ISMPC
 187   if (S_ISMPC (bits))
 188     return 'm';
 189 #endif
 190 #ifdef S_ISNWK
 191   if (S_ISNWK (bits))
 192     return 'n';
 193 #endif
 194   return '?';
 195 }
 196
 197 /* Look at read, write, and execute bits in BITS and set
 198    flags in CHARS accordingly.  */
 199
 200 static void
 201 rwx (short unsigned int bits, char *chars)
 202 {
 203   chars[0] = (bits & S_IRUSR) ? 'r' : '-';
 204   chars[1] = (bits & S_IWUSR) ? 'w' : '-';
 205   chars[2] = (bits & S_IXUSR) ? 'x' : '-';
 206 }
 207
 208 /* Set the 's' and 't' flags in file attributes string CHARS,
 209    according to the file mode BITS.  */
 210
 211 static void
 212 setst (short unsigned int bits, char *chars)
 213 {
 214 #ifdef S_ISUID
 215   if (bits & S_ISUID)
 216     {
 217       if (chars[3] != 'x')
 218         /* Set-uid, but not executable by owner.  */
 219         chars[3] = 'S';
 220       else
 221         chars[3] = 's';
 222     }
 223 #endif
 224 #ifdef S_ISGID
 225   if (bits & S_ISGID)
 226     {
 227       if (chars[6] != 'x')
 228         /* Set-gid, but not executable by group.  */
 229         chars[6] = 'S';
 230       else
 231         chars[6] = 's';
 232     }
 233 #endif
 234 #ifdef S_ISVTX
 235   if (bits & S_ISVTX)
 236     {
 237       if (chars[9] != 'x')
 238         /* Sticky, but not executable by others.  */
 239         chars[9] = 'T';
 240       else
 241         chars[9] = 't';
 242     }
 243 #endif
 244 }
 245