code.delx.au - gnu-emacs/blob - src/filemode.c

   1 /* filemode.c -- make a string describing file modes
   2    Copyright (C) 1985, 1990, 1993, 2001, 2002, 2003, 2004,
   3                  2005, 2006, 2007, 2008, 2009, 2010, 2011  Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3, or (at your option)
   8    any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software
  17    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  18    USA.  */
  19 \f
  20 #include <config.h>
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23
  24 #if !S_IRUSR
  25 # if S_IREAD
  26 #  define S_IRUSR S_IREAD
  27 # else
  28 #  define S_IRUSR 00400
  29 # endif
  30 #endif
  31
  32 #if !S_IWUSR
  33 # if S_IWRITE
  34 #  define S_IWUSR S_IWRITE
  35 # else
  36 #  define S_IWUSR 00200
  37 # endif
  38 #endif
  39
  40 #if !S_IXUSR
  41 # if S_IEXEC
  42 #  define S_IXUSR S_IEXEC
  43 # else
  44 #  define S_IXUSR 00100
  45 # endif
  46 #endif
  47
  48 #ifdef STAT_MACROS_BROKEN
  49 #undef S_ISBLK
  50 #undef S_ISCHR
  51 #undef S_ISDIR
  52 #undef S_ISFIFO
  53 #undef S_ISLNK
  54 #undef S_ISMPB
  55 #undef S_ISMPC
  56 #undef S_ISNWK
  57 #undef S_ISREG
  58 #undef S_ISSOCK
  59 #endif /* STAT_MACROS_BROKEN.  */
  60
  61 #if !defined(S_ISBLK) && defined(S_IFBLK)
  62 #define S_ISBLK(m) (((m) & S_IFMT) == S_IFBLK)
  63 #endif
  64 #if !defined(S_ISCHR) && defined(S_IFCHR)
  65 #define S_ISCHR(m) (((m) & S_IFMT) == S_IFCHR)
  66 #endif
  67 #if !defined(S_ISDIR) && defined(S_IFDIR)
  68 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
  69 #endif
  70 #if !defined(S_ISREG) && defined(S_IFREG)
  71 #define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
  72 #endif
  73 #if !defined(S_ISFIFO) && defined(S_IFIFO)
  74 #define S_ISFIFO(m) (((m) & S_IFMT) == S_IFIFO)
  75 #endif
  76 #if !defined(S_ISLNK) && defined(S_IFLNK)
  77 #define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
  78 #endif
  79 #if !defined(S_ISSOCK) && defined(S_IFSOCK)
  80 #define S_ISSOCK(m) (((m) & S_IFMT) == S_IFSOCK)
  81 #endif
  82 #if !defined(S_ISMPB) && defined(S_IFMPB) /* V7 */
  83 #define S_ISMPB(m) (((m) & S_IFMT) == S_IFMPB)
  84 #define S_ISMPC(m) (((m) & S_IFMT) == S_IFMPC)
  85 #endif
  86 #if !defined(S_ISNWK) && defined(S_IFNWK) /* HP/UX */
  87 #define S_ISNWK(m) (((m) & S_IFMT) == S_IFNWK)
  88 #endif
  89
  90 void mode_string (short unsigned int mode, char *str);
  91 static char ftypelet (long int bits);
  92 static void rwx (short unsigned int bits, char *chars);
  93 static void setst (short unsigned int bits, char *chars);
  94
  95 /* filemodestring - fill in string STR with an ls-style ASCII
  96    representation of the st_mode field of file stats block STATP.
  97    10 characters are stored in STR; no terminating null is added.
  98    The characters stored in STR are:
  99
 100    0    File type.  'd' for directory, 'c' for character
 101         special, 'b' for block special, 'm' for multiplex,
 102         'l' for symbolic link, 's' for socket, 'p' for fifo,
 103         '-' for regular, '?' for any other file type
 104
 105    1    'r' if the owner may read, '-' otherwise.
 106
 107    2    'w' if the owner may write, '-' otherwise.
 108
 109    3    'x' if the owner may execute, 's' if the file is
 110         set-user-id, '-' otherwise.
 111         'S' if the file is set-user-id, but the execute
 112         bit isn't set.
 113
 114    4    'r' if group members may read, '-' otherwise.
 115
 116    5    'w' if group members may write, '-' otherwise.
 117
 118    6    'x' if group members may execute, 's' if the file is
 119         set-group-id, '-' otherwise.
 120         'S' if it is set-group-id but not executable.
 121
 122    7    'r' if any user may read, '-' otherwise.
 123
 124    8    'w' if any user may write, '-' otherwise.
 125
 126    9    'x' if any user may execute, 't' if the file is "sticky"
 127         (will be retained in swap space after execution), '-'
 128         otherwise.
 129         'T' if the file is sticky but not executable.  */
 130
 131 void
 132 filemodestring (struct stat *statp, char *str)
 133 {
 134   mode_string (statp->st_mode, str);
 135 }
 136
 137 /* Like filemodestring, but only the relevant part of the `struct stat'
 138    is given as an argument.  */
 139
 140 void
 141 mode_string (short unsigned int mode, char *str)
 142 {
 143   str[0] = ftypelet ((long) mode);
 144   rwx ((mode & 0700) << 0, &str[1]);
 145   rwx ((mode & 0070) << 3, &str[4]);
 146   rwx ((mode & 0007) << 6, &str[7]);
 147   setst (mode, str);
 148 }
 149
 150 /* Return a character indicating the type of file described by
 151    file mode BITS:
 152    'd' for directories
 153    'b' for block special files
 154    'c' for character special files
 155    'm' for multiplexor files
 156    'l' for symbolic links
 157    's' for sockets
 158    'p' for fifos
 159    '-' for regular files
 160    '?' for any other file type.  */
 161
 162 static char
 163 ftypelet (long int bits)
 164 {
 165 #ifdef S_ISBLK
 166   if (S_ISBLK (bits))
 167     return 'b';
 168 #endif
 169   if (S_ISCHR (bits))
 170     return 'c';
 171   if (S_ISDIR (bits))
 172     return 'd';
 173   if (S_ISREG (bits))
 174     return '-';
 175 #ifdef S_ISFIFO
 176   if (S_ISFIFO (bits))
 177     return 'p';
 178 #endif
 179 #ifdef S_ISLNK
 180   if (S_ISLNK (bits))
 181     return 'l';
 182 #endif
 183 #ifdef S_ISSOCK
 184   if (S_ISSOCK (bits))
 185     return 's';
 186 #endif
 187 #ifdef S_ISMPC
 188   if (S_ISMPC (bits))
 189     return 'm';
 190 #endif
 191 #ifdef S_ISNWK
 192   if (S_ISNWK (bits))
 193     return 'n';
 194 #endif
 195   return '?';
 196 }
 197
 198 /* Look at read, write, and execute bits in BITS and set
 199    flags in CHARS accordingly.  */
 200
 201 static void
 202 rwx (short unsigned int bits, char *chars)
 203 {
 204   chars[0] = (bits & S_IRUSR) ? 'r' : '-';
 205   chars[1] = (bits & S_IWUSR) ? 'w' : '-';
 206   chars[2] = (bits & S_IXUSR) ? 'x' : '-';
 207 }
 208
 209 /* Set the 's' and 't' flags in file attributes string CHARS,
 210    according to the file mode BITS.  */
 211
 212 static void
 213 setst (short unsigned int bits, char *chars)
 214 {
 215 #ifdef S_ISUID
 216   if (bits & S_ISUID)
 217     {
 218       if (chars[3] != 'x')
 219         /* Set-uid, but not executable by owner.  */
 220         chars[3] = 'S';
 221       else
 222         chars[3] = 's';
 223     }
 224 #endif
 225 #ifdef S_ISGID
 226   if (bits & S_ISGID)
 227     {
 228       if (chars[6] != 'x')
 229         /* Set-gid, but not executable by group.  */
 230         chars[6] = 'S';
 231       else
 232         chars[6] = 's';
 233     }
 234 #endif
 235 #ifdef S_ISVTX
 236   if (bits & S_ISVTX)
 237     {
 238       if (chars[9] != 'x')
 239         /* Sticky, but not executable by others.  */
 240         chars[9] = 'T';
 241       else
 242         chars[9] = 't';
 243     }
 244 #endif
 245 }
 246