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 #if !S_IRUSR
  26 # if S_IREAD
  27 #  define S_IRUSR S_IREAD
  28 # else
  29 #  define S_IRUSR 00400
  30 # endif
  31 #endif
  32
  33 #if !S_IWUSR
  34 # if S_IWRITE
  35 #  define S_IWUSR S_IWRITE
  36 # else
  37 #  define S_IWUSR 00200
  38 # endif
  39 #endif
  40
  41 #if !S_IXUSR
  42 # if S_IEXEC
  43 #  define S_IXUSR S_IEXEC
  44 # else
  45 #  define S_IXUSR 00100
  46 # endif
  47 #endif
  48
  49 #ifdef STAT_MACROS_BROKEN
  50 #undef S_ISBLK
  51 #undef S_ISCHR
  52 #undef S_ISDIR
  53 #undef S_ISFIFO
  54 #undef S_ISLNK
  55 #undef S_ISMPB
  56 #undef S_ISMPC
  57 #undef S_ISNWK
  58 #undef S_ISREG
  59 #undef S_ISSOCK
  60 #endif /* STAT_MACROS_BROKEN.  */
  61
  62 #if !defined(S_ISBLK) && defined(S_IFBLK)
  63 #define S_ISBLK(m) (((m) & S_IFMT) == S_IFBLK)
  64 #endif
  65 #if !defined(S_ISCHR) && defined(S_IFCHR)
  66 #define S_ISCHR(m) (((m) & S_IFMT) == S_IFCHR)
  67 #endif
  68 #if !defined(S_ISDIR) && defined(S_IFDIR)
  69 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
  70 #endif
  71 #if !defined(S_ISREG) && defined(S_IFREG)
  72 #define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
  73 #endif
  74 #if !defined(S_ISFIFO) && defined(S_IFIFO)
  75 #define S_ISFIFO(m) (((m) & S_IFMT) == S_IFIFO)
  76 #endif
  77 #if !defined(S_ISLNK) && defined(S_IFLNK)
  78 #define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
  79 #endif
  80 #if !defined(S_ISSOCK) && defined(S_IFSOCK)
  81 #define S_ISSOCK(m) (((m) & S_IFMT) == S_IFSOCK)
  82 #endif
  83 #if !defined(S_ISMPB) && defined(S_IFMPB) /* V7 */
  84 #define S_ISMPB(m) (((m) & S_IFMT) == S_IFMPB)
  85 #define S_ISMPC(m) (((m) & S_IFMT) == S_IFMPC)
  86 #endif
  87 #if !defined(S_ISNWK) && defined(S_IFNWK) /* HP/UX */
  88 #define S_ISNWK(m) (((m) & S_IFMT) == S_IFNWK)
  89 #endif
  90
  91 void mode_string ();
  92 static char ftypelet ();
  93 static void rwx ();
  94 static void setst ();
  95
  96 /* filemodestring - fill in string STR with an ls-style ASCII
  97    representation of the st_mode field of file stats block STATP.
  98    10 characters are stored in STR; no terminating null is added.
  99    The characters stored in STR are:
 100
 101    0    File type.  'd' for directory, 'c' for character
 102         special, 'b' for block special, 'm' for multiplex,
 103         'l' for symbolic link, 's' for socket, 'p' for fifo,
 104         '-' for regular, '?' for any other file type
 105
 106    1    'r' if the owner may read, '-' otherwise.
 107
 108    2    'w' if the owner may write, '-' otherwise.
 109
 110    3    'x' if the owner may execute, 's' if the file is
 111         set-user-id, '-' otherwise.
 112         'S' if the file is set-user-id, but the execute
 113         bit isn't set.
 114
 115    4    'r' if group members may read, '-' otherwise.
 116
 117    5    'w' if group members may write, '-' otherwise.
 118
 119    6    'x' if group members may execute, 's' if the file is
 120         set-group-id, '-' otherwise.
 121         'S' if it is set-group-id but not executable.
 122
 123    7    'r' if any user may read, '-' otherwise.
 124
 125    8    'w' if any user may write, '-' otherwise.
 126
 127    9    'x' if any user may execute, 't' if the file is "sticky"
 128         (will be retained in swap space after execution), '-'
 129         otherwise.
 130         'T' if the file is sticky but not executable.  */
 131
 132 void
 133 filemodestring (statp, str)
 134      struct stat *statp;
 135      char *str;
 136 {
 137   mode_string (statp->st_mode, str);
 138 }
 139
 140 /* Like filemodestring, but only the relevant part of the `struct stat'
 141    is given as an argument.  */
 142
 143 void
 144 mode_string (mode, str)
 145      unsigned short mode;
 146      char *str;
 147 {
 148   str[0] = ftypelet ((long) mode);
 149   rwx ((mode & 0700) << 0, &str[1]);
 150   rwx ((mode & 0070) << 3, &str[4]);
 151   rwx ((mode & 0007) << 6, &str[7]);
 152   setst (mode, str);
 153 }
 154
 155 /* Return a character indicating the type of file described by
 156    file mode BITS:
 157    'd' for directories
 158    'b' for block special files
 159    'c' for character special files
 160    'm' for multiplexor files
 161    'l' for symbolic links
 162    's' for sockets
 163    'p' for fifos
 164    '-' for regular files
 165    '?' for any other file type.  */
 166
 167 static char
 168 ftypelet (bits)
 169      long bits;
 170 {
 171 #ifdef S_ISBLK
 172   if (S_ISBLK (bits))
 173     return 'b';
 174 #endif
 175   if (S_ISCHR (bits))
 176     return 'c';
 177   if (S_ISDIR (bits))
 178     return 'd';
 179   if (S_ISREG (bits))
 180     return '-';
 181 #ifdef S_ISFIFO
 182   if (S_ISFIFO (bits))
 183     return 'p';
 184 #endif
 185 #ifdef S_ISLNK
 186   if (S_ISLNK (bits))
 187     return 'l';
 188 #endif
 189 #ifdef S_ISSOCK
 190   if (S_ISSOCK (bits))
 191     return 's';
 192 #endif
 193 #ifdef S_ISMPC
 194   if (S_ISMPC (bits))
 195     return 'm';
 196 #endif
 197 #ifdef S_ISNWK
 198   if (S_ISNWK (bits))
 199     return 'n';
 200 #endif
 201   return '?';
 202 }
 203
 204 /* Look at read, write, and execute bits in BITS and set
 205    flags in CHARS accordingly.  */
 206
 207 static void
 208 rwx (bits, chars)
 209      unsigned short bits;
 210      char *chars;
 211 {
 212   chars[0] = (bits & S_IRUSR) ? 'r' : '-';
 213   chars[1] = (bits & S_IWUSR) ? 'w' : '-';
 214   chars[2] = (bits & S_IXUSR) ? 'x' : '-';
 215 }
 216
 217 /* Set the 's' and 't' flags in file attributes string CHARS,
 218    according to the file mode BITS.  */
 219
 220 static void
 221 setst (bits, chars)
 222      unsigned short bits;
 223      char *chars;
 224 {
 225 #ifdef S_ISUID
 226   if (bits & S_ISUID)
 227     {
 228       if (chars[3] != 'x')
 229         /* Set-uid, but not executable by owner.  */
 230         chars[3] = 'S';
 231       else
 232         chars[3] = 's';
 233     }
 234 #endif
 235 #ifdef S_ISGID
 236   if (bits & S_ISGID)
 237     {
 238       if (chars[6] != 'x')
 239         /* Set-gid, but not executable by group.  */
 240         chars[6] = 'S';
 241       else
 242         chars[6] = 's';
 243     }
 244 #endif
 245 #ifdef S_ISVTX
 246   if (bits & S_ISVTX)
 247     {
 248       if (chars[9] != 'x')
 249         /* Sticky, but not executable by others.  */
 250         chars[9] = 'T';
 251       else
 252         chars[9] = 't';
 253     }
 254 #endif
 255 }