1 /* chown -- change user and group ownership of files
2 Copyright (C) 1989-2023 Free Software Foundation, Inc.
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 of the License, or
7 (at your option) any later version.
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.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
17 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
21 #include <sys/types.h>
25 #include "chown-core.h"
28 #include "root-dev-ino.h"
31 /* The official name of this program (e.g., no 'g' prefix). */
32 #define PROGRAM_NAME "chown"
35 proper_name ("David MacKenzie"), \
36 proper_name ("Jim Meyering")
38 /* The argument to the --reference option. Use the owner and group IDs
39 of this file. This file must exist. */
40 static char *reference_file
;
42 /* For long options that have no equivalent short option, use a
43 non-character as a pseudo short option, starting with CHAR_MAX + 1. */
46 DEREFERENCE_OPTION
= CHAR_MAX
+ 1,
53 static struct option
const long_options
[] =
55 {"recursive", no_argument
, nullptr, 'R'},
56 {"changes", no_argument
, nullptr, 'c'},
57 {"dereference", no_argument
, nullptr, DEREFERENCE_OPTION
},
58 {"from", required_argument
, nullptr, FROM_OPTION
},
59 {"no-dereference", no_argument
, nullptr, 'h'},
60 {"no-preserve-root", no_argument
, nullptr, NO_PRESERVE_ROOT
},
61 {"preserve-root", no_argument
, nullptr, PRESERVE_ROOT
},
62 {"quiet", no_argument
, nullptr, 'f'},
63 {"silent", no_argument
, nullptr, 'f'},
64 {"reference", required_argument
, nullptr, REFERENCE_FILE_OPTION
},
65 {"verbose", no_argument
, nullptr, 'v'},
66 {GETOPT_HELP_OPTION_DECL
},
67 {GETOPT_VERSION_OPTION_DECL
},
68 {nullptr, 0, nullptr, 0}
74 if (status
!= EXIT_SUCCESS
)
79 Usage: %s [OPTION]... [OWNER][:[GROUP]] FILE...\n\
80 or: %s [OPTION]... --reference=RFILE FILE...\n\
82 program_name
, program_name
);
84 Change the owner and/or group of each FILE to OWNER and/or GROUP.\n\
85 With --reference, change the owner and group of each FILE to those of RFILE.\n\
89 -c, --changes like verbose but report only when a change is made\n\
90 -f, --silent, --quiet suppress most error messages\n\
91 -v, --verbose output a diagnostic for every file processed\n\
94 --dereference affect the referent of each symbolic link (this is\n\
95 the default), rather than the symbolic link itself\n\
96 -h, --no-dereference affect symbolic links instead of any referenced file\n\
99 (useful only on systems that can change the\n\
100 ownership of a symlink)\n\
103 --from=CURRENT_OWNER:CURRENT_GROUP\n\
104 change the owner and/or group of each file only if\n\
105 its current owner and/or group match those specified\n\
106 here. Either may be omitted, in which case a match\n\
107 is not required for the omitted attribute\n\
110 --no-preserve-root do not treat '/' specially (the default)\n\
111 --preserve-root fail to operate recursively on '/'\n\
114 --reference=RFILE use RFILE's owner and group rather than specifying\n\
115 OWNER:GROUP values. RFILE is always dereferenced.\n\
118 -R, --recursive operate on files and directories recursively\n\
122 The following options modify how a hierarchy is traversed when the -R\n\
123 option is also specified. If more than one is specified, only the final\n\
126 -H if a command line argument is a symbolic link\n\
127 to a directory, traverse it\n\
128 -L traverse every symbolic link to a directory\n\
130 -P do not traverse any symbolic links (default)\n\
133 fputs (HELP_OPTION_DESCRIPTION
, stdout
);
134 fputs (VERSION_OPTION_DESCRIPTION
, stdout
);
137 Owner is unchanged if missing. Group is unchanged if missing, but changed\n\
138 to login group if implied by a ':' following a symbolic OWNER.\n\
139 OWNER and GROUP may be numeric as well as symbolic.\n\
144 %s root /u Change the owner of /u to \"root\".\n\
145 %s root:staff /u Likewise, but also change its group to \"staff\".\n\
146 %s -hR root /u Change the owner of /u and subfiles to \"root\".\n\
148 program_name
, program_name
, program_name
);
149 emit_ancillary_info (PROGRAM_NAME
);
155 main (int argc
, char **argv
)
157 bool preserve_root
= false;
159 uid_t uid
= -1; /* Specified uid; -1 if not to be changed. */
160 gid_t gid
= -1; /* Specified gid; -1 if not to be changed. */
162 /* Change the owner (group) of a file only if it has this uid (gid).
163 -1 means there's no restriction. */
164 uid_t required_uid
= -1;
165 gid_t required_gid
= -1;
167 /* Bit flags that control how fts works. */
168 int bit_flags
= FTS_PHYSICAL
;
170 /* 1 if --dereference, 0 if --no-dereference, -1 if neither has been
172 int dereference
= -1;
174 struct Chown_option chopt
;
178 initialize_main (&argc
, &argv
);
179 set_program_name (argv
[0]);
180 setlocale (LC_ALL
, "");
181 bindtextdomain (PACKAGE
, LOCALEDIR
);
182 textdomain (PACKAGE
);
184 atexit (close_stdout
);
188 while ((optc
= getopt_long (argc
, argv
, "HLPRcfhv", long_options
, nullptr))
193 case 'H': /* Traverse command-line symlinks-to-directories. */
194 bit_flags
= FTS_COMFOLLOW
| FTS_PHYSICAL
;
197 case 'L': /* Traverse all symlinks-to-directories. */
198 bit_flags
= FTS_LOGICAL
;
201 case 'P': /* Traverse no symlinks-to-directories. */
202 bit_flags
= FTS_PHYSICAL
;
205 case 'h': /* --no-dereference: affect symlinks */
209 case DEREFERENCE_OPTION
: /* --dereference: affect the referent
214 case NO_PRESERVE_ROOT
:
215 preserve_root
= false;
219 preserve_root
= true;
222 case REFERENCE_FILE_OPTION
:
223 reference_file
= optarg
;
229 char const *e
= parse_user_spec_warn (optarg
,
230 &required_uid
, &required_gid
,
231 nullptr, nullptr, &warn
);
233 error (warn
? 0 : EXIT_FAILURE
, 0, "%s: %s", e
, quote (optarg
));
238 chopt
.recurse
= true;
242 chopt
.verbosity
= V_changes_only
;
246 chopt
.force_silent
= true;
250 chopt
.verbosity
= V_high
;
253 case_GETOPT_HELP_CHAR
;
254 case_GETOPT_VERSION_CHAR (PROGRAM_NAME
, AUTHORS
);
256 usage (EXIT_FAILURE
);
262 if (bit_flags
== FTS_PHYSICAL
)
264 if (dereference
== 1)
265 error (EXIT_FAILURE
, 0,
266 _("-R --dereference requires either -H or -L"));
272 bit_flags
= FTS_PHYSICAL
;
274 chopt
.affect_symlink_referent
= (dereference
!= 0);
276 if (argc
- optind
< (reference_file
? 1 : 2))
279 error (0, 0, _("missing operand"));
281 error (0, 0, _("missing operand after %s"), quote (argv
[argc
- 1]));
282 usage (EXIT_FAILURE
);
287 struct stat ref_stats
;
288 if (stat (reference_file
, &ref_stats
))
289 error (EXIT_FAILURE
, errno
, _("failed to get attributes of %s"),
290 quoteaf (reference_file
));
292 uid
= ref_stats
.st_uid
;
293 gid
= ref_stats
.st_gid
;
294 chopt
.user_name
= uid_to_name (ref_stats
.st_uid
);
295 chopt
.group_name
= gid_to_name (ref_stats
.st_gid
);
300 char const *e
= parse_user_spec_warn (argv
[optind
], &uid
, &gid
,
302 &chopt
.group_name
, &warn
);
304 error (warn
? 0 : EXIT_FAILURE
, 0, "%s: %s", e
, quote (argv
[optind
]));
306 /* If a group is specified but no user, set the user name to the
307 empty string so that diagnostics say "ownership :GROUP"
308 rather than "group GROUP". */
309 if (!chopt
.user_name
&& chopt
.group_name
)
310 chopt
.user_name
= xstrdup ("");
315 if (chopt
.recurse
&& preserve_root
)
317 static struct dev_ino dev_ino_buf
;
318 chopt
.root_dev_ino
= get_root_dev_ino (&dev_ino_buf
);
319 if (chopt
.root_dev_ino
== nullptr)
320 error (EXIT_FAILURE
, errno
, _("failed to get attributes of %s"),
324 bit_flags
|= FTS_DEFER_STAT
;
325 ok
= chown_files (argv
+ optind
, bit_flags
,
327 required_uid
, required_gid
, &chopt
);
329 main_exit (ok
? EXIT_SUCCESS
: EXIT_FAILURE
);