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"
30 #include "root-dev-ino.h"
33 /* The official name of this program (e.g., no 'g' prefix). */
34 #define PROGRAM_NAME "chown"
37 proper_name ("David MacKenzie"), \
38 proper_name ("Jim Meyering")
40 /* The argument to the --reference option. Use the owner and group IDs
41 of this file. This file must exist. */
42 static char *reference_file
;
44 /* For long options that have no equivalent short option, use a
45 non-character as a pseudo short option, starting with CHAR_MAX + 1. */
48 DEREFERENCE_OPTION
= CHAR_MAX
+ 1,
55 static struct option
const long_options
[] =
57 {"recursive", no_argument
, NULL
, 'R'},
58 {"changes", no_argument
, NULL
, 'c'},
59 {"dereference", no_argument
, NULL
, DEREFERENCE_OPTION
},
60 {"from", required_argument
, NULL
, FROM_OPTION
},
61 {"no-dereference", no_argument
, NULL
, 'h'},
62 {"no-preserve-root", no_argument
, NULL
, NO_PRESERVE_ROOT
},
63 {"preserve-root", no_argument
, NULL
, PRESERVE_ROOT
},
64 {"quiet", no_argument
, NULL
, 'f'},
65 {"silent", no_argument
, NULL
, 'f'},
66 {"reference", required_argument
, NULL
, REFERENCE_FILE_OPTION
},
67 {"verbose", no_argument
, NULL
, 'v'},
68 {GETOPT_HELP_OPTION_DECL
},
69 {GETOPT_VERSION_OPTION_DECL
},
76 if (status
!= EXIT_SUCCESS
)
81 Usage: %s [OPTION]... [OWNER][:[GROUP]] FILE...\n\
82 or: %s [OPTION]... --reference=RFILE FILE...\n\
84 program_name
, program_name
);
86 Change the owner and/or group of each FILE to OWNER and/or GROUP.\n\
87 With --reference, change the owner and group of each FILE to those of RFILE.\n\
91 -c, --changes like verbose but report only when a change is made\n\
92 -f, --silent, --quiet suppress most error messages\n\
93 -v, --verbose output a diagnostic for every file processed\n\
96 --dereference affect the referent of each symbolic link (this is\n\
97 the default), rather than the symbolic link itself\n\
98 -h, --no-dereference affect symbolic links instead of any referenced file\n\
101 (useful only on systems that can change the\n\
102 ownership of a symlink)\n\
105 --from=CURRENT_OWNER:CURRENT_GROUP\n\
106 change the owner and/or group of each file only if\n\
107 its current owner and/or group match those specified\n\
108 here. Either may be omitted, in which case a match\n\
109 is not required for the omitted attribute\n\
112 --no-preserve-root do not treat '/' specially (the default)\n\
113 --preserve-root fail to operate recursively on '/'\n\
116 --reference=RFILE use RFILE's owner and group rather than specifying\n\
117 OWNER:GROUP values. RFILE is always dereferenced.\n\
120 -R, --recursive operate on files and directories recursively\n\
124 The following options modify how a hierarchy is traversed when the -R\n\
125 option is also specified. If more than one is specified, only the final\n\
128 -H if a command line argument is a symbolic link\n\
129 to a directory, traverse it\n\
130 -L traverse every symbolic link to a directory\n\
132 -P do not traverse any symbolic links (default)\n\
135 fputs (HELP_OPTION_DESCRIPTION
, stdout
);
136 fputs (VERSION_OPTION_DESCRIPTION
, stdout
);
139 Owner is unchanged if missing. Group is unchanged if missing, but changed\n\
140 to login group if implied by a ':' following a symbolic OWNER.\n\
141 OWNER and GROUP may be numeric as well as symbolic.\n\
146 %s root /u Change the owner of /u to \"root\".\n\
147 %s root:staff /u Likewise, but also change its group to \"staff\".\n\
148 %s -hR root /u Change the owner of /u and subfiles to \"root\".\n\
150 program_name
, program_name
, program_name
);
151 emit_ancillary_info (PROGRAM_NAME
);
157 main (int argc
, char **argv
)
159 bool preserve_root
= false;
161 uid_t uid
= -1; /* Specified uid; -1 if not to be changed. */
162 gid_t gid
= -1; /* Specified gid; -1 if not to be changed. */
164 /* Change the owner (group) of a file only if it has this uid (gid).
165 -1 means there's no restriction. */
166 uid_t required_uid
= -1;
167 gid_t required_gid
= -1;
169 /* Bit flags that control how fts works. */
170 int bit_flags
= FTS_PHYSICAL
;
172 /* 1 if --dereference, 0 if --no-dereference, -1 if neither has been
174 int dereference
= -1;
176 struct Chown_option chopt
;
180 initialize_main (&argc
, &argv
);
181 set_program_name (argv
[0]);
182 setlocale (LC_ALL
, "");
183 bindtextdomain (PACKAGE
, LOCALEDIR
);
184 textdomain (PACKAGE
);
186 atexit (close_stdout
);
190 while ((optc
= getopt_long (argc
, argv
, "HLPRcfhv", long_options
, NULL
))
195 case 'H': /* Traverse command-line symlinks-to-directories. */
196 bit_flags
= FTS_COMFOLLOW
| FTS_PHYSICAL
;
199 case 'L': /* Traverse all symlinks-to-directories. */
200 bit_flags
= FTS_LOGICAL
;
203 case 'P': /* Traverse no symlinks-to-directories. */
204 bit_flags
= FTS_PHYSICAL
;
207 case 'h': /* --no-dereference: affect symlinks */
211 case DEREFERENCE_OPTION
: /* --dereference: affect the referent
216 case NO_PRESERVE_ROOT
:
217 preserve_root
= false;
221 preserve_root
= true;
224 case REFERENCE_FILE_OPTION
:
225 reference_file
= optarg
;
231 char const *e
= parse_user_spec_warn (optarg
,
232 &required_uid
, &required_gid
,
235 error (warn
? 0 : EXIT_FAILURE
, 0, "%s: %s", e
, quote (optarg
));
240 chopt
.recurse
= true;
244 chopt
.verbosity
= V_changes_only
;
248 chopt
.force_silent
= true;
252 chopt
.verbosity
= V_high
;
255 case_GETOPT_HELP_CHAR
;
256 case_GETOPT_VERSION_CHAR (PROGRAM_NAME
, AUTHORS
);
258 usage (EXIT_FAILURE
);
264 if (bit_flags
== FTS_PHYSICAL
)
266 if (dereference
== 1)
267 die (EXIT_FAILURE
, 0,
268 _("-R --dereference requires either -H or -L"));
274 bit_flags
= FTS_PHYSICAL
;
276 chopt
.affect_symlink_referent
= (dereference
!= 0);
278 if (argc
- optind
< (reference_file
? 1 : 2))
281 error (0, 0, _("missing operand"));
283 error (0, 0, _("missing operand after %s"), quote (argv
[argc
- 1]));
284 usage (EXIT_FAILURE
);
289 struct stat ref_stats
;
290 if (stat (reference_file
, &ref_stats
))
291 die (EXIT_FAILURE
, errno
, _("failed to get attributes of %s"),
292 quoteaf (reference_file
));
294 uid
= ref_stats
.st_uid
;
295 gid
= ref_stats
.st_gid
;
296 chopt
.user_name
= uid_to_name (ref_stats
.st_uid
);
297 chopt
.group_name
= gid_to_name (ref_stats
.st_gid
);
302 char const *e
= parse_user_spec_warn (argv
[optind
], &uid
, &gid
,
304 &chopt
.group_name
, &warn
);
306 error (warn
? 0 : EXIT_FAILURE
, 0, "%s: %s", e
, quote (argv
[optind
]));
308 /* If a group is specified but no user, set the user name to the
309 empty string so that diagnostics say "ownership :GROUP"
310 rather than "group GROUP". */
311 if (!chopt
.user_name
&& chopt
.group_name
)
312 chopt
.user_name
= xstrdup ("");
317 if (chopt
.recurse
&& preserve_root
)
319 static struct dev_ino dev_ino_buf
;
320 chopt
.root_dev_ino
= get_root_dev_ino (&dev_ino_buf
);
321 if (chopt
.root_dev_ino
== NULL
)
322 die (EXIT_FAILURE
, errno
, _("failed to get attributes of %s"),
326 bit_flags
|= FTS_DEFER_STAT
;
327 ok
= chown_files (argv
+ optind
, bit_flags
,
329 required_uid
, required_gid
, &chopt
);
331 main_exit (ok
? EXIT_SUCCESS
: EXIT_FAILURE
);