src/chown.c

   1 /* chown -- change user and group ownership of files
   2    Copyright (C) 89, 90, 91, 95, 1996 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 Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /*
  19               |                       user
  20               | unchanged                 explicit
  21  -------------|-------------------------+-------------------------|
  22  g unchanged  | ---                     | chown u                 |
  23  r            |-------------------------+-------------------------|
  24  o explicit   | chgrp g or chown .g     | chown u.g               |
  25  u            |-------------------------+-------------------------|
  26  p from passwd| ---                     | chown u.                |
  27               |-------------------------+-------------------------|
  28
  29    Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
  30
  31 #include <config.h>
  32 #include <stdio.h>
  33 #include <sys/types.h>
  34 #include <pwd.h>
  35 #include <grp.h>
  36 #include <getopt.h>
  37
  38 #include "system.h"
  39 #include "error.h"
  40
  41 #ifndef _POSIX_VERSION
  42 struct passwd *getpwnam ();
  43 struct group *getgrnam ();
  44 struct group *getgrgid ();
  45 #endif
  46
  47 #ifndef HAVE_ENDPWENT
  48 # define endpwent() ((void) 0)
  49 #endif
  50
  51 #ifdef HAVE_LCHOWN
  52 # define LCHOWN(FILE, OWNER, GROUP) lchown (FILE, OWNER, GROUP)
  53 #else
  54 # define LCHOWN(FILE, OWNER, GROUP) 1
  55 #endif
  56
  57 char *savedir ();
  58 char *parse_user_spec ();
  59 void strip_trailing_slashes ();
  60 char *xmalloc ();
  61 char *xrealloc ();
  62
  63 static int change_dir_owner __P ((char *dir, uid_t user, gid_t group,
  64                                   struct stat *statp));
  65
  66 /* The name the program was run with. */
  67 char *program_name;
  68
  69 /* If nonzero, and the systems has support for it, change the ownership
  70    of symbolic links rather than any files they point to.  */
  71 static int change_symlinks;
  72
  73 /* If nonzero, change the ownership of directories recursively. */
  74 static int recurse;
  75
  76 /* If nonzero, force silence (no error messages). */
  77 static int force_silent;
  78
  79 /* If nonzero, describe the files we process. */
  80 static int verbose;
  81
  82 /* If nonzero, describe only owners or groups that change. */
  83 static int changes_only;
  84
  85 /* The name of the user to which ownership of the files is being given. */
  86 static char *username;
  87
  88 /* The name of the group to which ownership of the files is being given. */
  89 static char *groupname;
  90
  91 /* If nonzero, display usage information and exit.  */
  92 static int show_help;
  93
  94 /* If nonzero, print the version on standard output and exit.  */
  95 static int show_version;
  96
  97 static struct option const long_options[] =
  98 {
  99   {"recursive", no_argument, 0, 'R'},
 100   {"changes", no_argument, 0, 'c'},
 101   {"no-dereference", no_argument, 0, 'h'},
 102   {"quiet", no_argument, 0, 'f'},
 103   {"silent", no_argument, 0, 'f'},
 104   {"verbose", no_argument, 0, 'v'},
 105   {"help", no_argument, &show_help, 1},
 106   {"version", no_argument, &show_version, 1},
 107   {0, 0, 0, 0}
 108 };
 109
 110 /* Tell the user the user and group names to which ownership of FILE
 111    has been given; if CHANGED is zero, FILE had those owners already. */
 112
 113 static void
 114 describe_change (char *file, int changed)
 115 {
 116   if (changed)
 117     printf (_("owner of %s changed to "), file);
 118   else
 119     printf (_("owner of %s retained as "), file);
 120   if (groupname)
 121     printf ("%s.%s\n", username, groupname);
 122   else
 123     printf ("%s\n", username);
 124 }
 125
 126 /* Change the ownership of FILE to UID USER and GID GROUP.
 127    If it is a directory and -R is given, recurse.
 128    Return 0 if successful, 1 if errors occurred. */
 129
 130 static int
 131 change_file_owner (char *file, uid_t user, gid_t group)
 132 {
 133   struct stat file_stats;
 134   uid_t newuser;
 135   gid_t newgroup;
 136   int errors = 0;
 137
 138   if (lstat (file, &file_stats))
 139     {
 140       if (force_silent == 0)
 141         error (0, errno, "%s", file);
 142       return 1;
 143     }
 144
 145   newuser = user == (uid_t) -1 ? file_stats.st_uid : user;
 146   newgroup = group == (gid_t) -1 ? file_stats.st_gid : group;
 147   if (newuser != file_stats.st_uid || newgroup != file_stats.st_gid)
 148     {
 149       int fail;
 150
 151       if (verbose)
 152         describe_change (file, 1);
 153
 154       if (change_symlinks)
 155         fail = LCHOWN (file, newuser, newgroup);
 156       else
 157         fail = chown (file, newuser, newgroup);
 158
 159       if (fail)
 160         {
 161           if (force_silent == 0)
 162             error (0, errno, "%s", file);
 163           errors = 1;
 164         }
 165     }
 166   else if (verbose && changes_only == 0)
 167     describe_change (file, 0);
 168
 169   if (recurse && S_ISDIR (file_stats.st_mode))
 170     errors |= change_dir_owner (file, user, group, &file_stats);
 171   return errors;
 172 }
 173
 174 /* Recursively change the ownership of the files in directory DIR
 175    to UID USER and GID GROUP.
 176    STATP points to the results of lstat on DIR.
 177    Return 0 if successful, 1 if errors occurred. */
 178
 179 static int
 180 change_dir_owner (char *dir, uid_t user, gid_t group, struct stat *statp)
 181 {
 182   char *name_space, *namep;
 183   char *path;                   /* Full path of each entry to process. */
 184   unsigned dirlength;           /* Length of `dir' and '\0'. */
 185   unsigned filelength;          /* Length of each pathname to process. */
 186   unsigned pathlength;          /* Bytes allocated for `path'. */
 187   int errors = 0;
 188
 189   errno = 0;
 190   name_space = savedir (dir, statp->st_size);
 191   if (name_space == NULL)
 192     {
 193       if (errno)
 194         {
 195           if (force_silent == 0)
 196             error (0, errno, "%s", dir);
 197           return 1;
 198         }
 199       else
 200         error (1, 0, _("virtual memory exhausted"));
 201     }
 202
 203   dirlength = strlen (dir) + 1; /* + 1 is for the trailing '/'. */
 204   pathlength = dirlength + 1;
 205   /* Give `path' a dummy value; it will be reallocated before first use. */
 206   path = xmalloc (pathlength);
 207   strcpy (path, dir);
 208   path[dirlength - 1] = '/';
 209
 210   for (namep = name_space; *namep; namep += filelength - dirlength)
 211     {
 212       filelength = dirlength + strlen (namep) + 1;
 213       if (filelength > pathlength)
 214         {
 215           pathlength = filelength * 2;
 216           path = xrealloc (path, pathlength);
 217         }
 218       strcpy (path + dirlength, namep);
 219       errors |= change_file_owner (path, user, group);
 220     }
 221   free (path);
 222   free (name_space);
 223   return errors;
 224 }
 225
 226 static void
 227 usage (int status)
 228 {
 229   if (status != 0)
 230     fprintf (stderr, _("Try `%s --help' for more information.\n"),
 231              program_name);
 232   else
 233     {
 234       printf (_("\
 235 Usage: %s [OPTION]... OWNER[.[GROUP]] FILE...\n\
 236   or:  %s [OPTION]... .[GROUP] FILE...\n\
 237 "),
 238               program_name, program_name);
 239       printf (_("\
 240 Change the owner and/or group of each FILE to OWNER and/or GROUP.\n\
 241 \n\
 242   -c, --changes          be verbose whenever change occurs\n\
 243   -h, --no-dereference   affect symbolic links instead of any referenced file\n\
 244                          (available only on systems with lchown system call)\n\
 245   -f, --silent, --quiet  suppress most error messages\n\
 246   -v, --verbose          explain what is being done\n\
 247   -R, --recursive        change files and directories recursively\n\
 248       --help             display this help and exit\n\
 249       --version          output version information and exit\n\
 250 \n\
 251 Owner is unchanged if missing.  Group is unchanged if missing, but changed\n\
 252 to login group if implied by a period.  A colon may replace the period.\n"));
 253     }
 254   exit (status);
 255 }
 256
 257 int
 258 main (int argc, char **argv)
 259 {
 260   uid_t user = (uid_t) -1;      /* New uid; -1 if not to be changed. */
 261   gid_t group = (uid_t) -1;     /* New gid; -1 if not to be changed. */
 262   int errors = 0;
 263   int optc;
 264   char *e;
 265
 266   program_name = argv[0];
 267   setlocale (LC_ALL, "");
 268   bindtextdomain (PACKAGE, LOCALEDIR);
 269   textdomain (PACKAGE);
 270
 271   recurse = force_silent = verbose = changes_only = 0;
 272
 273   while ((optc = getopt_long (argc, argv, "Rcfhv", long_options, (int *) 0))
 274          != EOF)
 275     {
 276       switch (optc)
 277         {
 278         case 0:
 279           break;
 280         case 'R':
 281           recurse = 1;
 282           break;
 283         case 'c':
 284           verbose = 1;
 285           changes_only = 1;
 286           break;
 287         case 'f':
 288           force_silent = 1;
 289           break;
 290         case 'h':
 291           change_symlinks = 1;
 292           break;
 293         case 'v':
 294           verbose = 1;
 295           break;
 296         default:
 297           usage (1);
 298         }
 299     }
 300
 301   if (show_version)
 302     {
 303       printf ("chown - %s\n", PACKAGE_VERSION);
 304       exit (0);
 305     }
 306
 307   if (show_help)
 308     usage (0);
 309
 310   if (optind >= argc - 1)
 311     {
 312       error (0, 0, _("too few arguments"));
 313       usage (1);
 314     }
 315
 316 #ifndef HAVE_LCHOWN
 317   if (change_symlinks)
 318     {
 319       error (1, 0, _("--no-dereference (-h) is not supported on this system"));
 320     }
 321 #endif
 322
 323   e = parse_user_spec (argv[optind], &user, &group, &username, &groupname);
 324   if (e)
 325     error (1, 0, "%s: %s", argv[optind], e);
 326   if (username == NULL)
 327     username = "";
 328
 329   for (++optind; optind < argc; ++optind)
 330     {
 331       strip_trailing_slashes (argv[optind]);
 332       errors |= change_file_owner (argv[optind], user, group);
 333     }
 334
 335   exit (errors);
 336 }