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Diffstat (limited to 'src/chown.c')
-rw-r--r-- | src/chown.c | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/src/chown.c b/src/chown.c new file mode 100644 index 0000000..c51955b --- /dev/null +++ b/src/chown.c @@ -0,0 +1,331 @@ +/* chown -- change user and group ownership of files + Copyright (C) 1989-2020 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */ + +#include <config.h> +#include <stdio.h> +#include <sys/types.h> +#include <getopt.h> + +#include "system.h" +#include "chown-core.h" +#include "die.h" +#include "error.h" +#include "fts_.h" +#include "quote.h" +#include "root-dev-ino.h" +#include "userspec.h" + +/* The official name of this program (e.g., no 'g' prefix). */ +#define PROGRAM_NAME "chown" + +#define AUTHORS \ + proper_name ("David MacKenzie"), \ + proper_name ("Jim Meyering") + +/* The argument to the --reference option. Use the owner and group IDs + of this file. This file must exist. */ +static char *reference_file; + +/* For long options that have no equivalent short option, use a + non-character as a pseudo short option, starting with CHAR_MAX + 1. */ +enum +{ + DEREFERENCE_OPTION = CHAR_MAX + 1, + FROM_OPTION, + NO_PRESERVE_ROOT, + PRESERVE_ROOT, + REFERENCE_FILE_OPTION +}; + +static struct option const long_options[] = +{ + {"recursive", no_argument, NULL, 'R'}, + {"changes", no_argument, NULL, 'c'}, + {"dereference", no_argument, NULL, DEREFERENCE_OPTION}, + {"from", required_argument, NULL, FROM_OPTION}, + {"no-dereference", no_argument, NULL, 'h'}, + {"no-preserve-root", no_argument, NULL, NO_PRESERVE_ROOT}, + {"preserve-root", no_argument, NULL, PRESERVE_ROOT}, + {"quiet", no_argument, NULL, 'f'}, + {"silent", no_argument, NULL, 'f'}, + {"reference", required_argument, NULL, REFERENCE_FILE_OPTION}, + {"verbose", no_argument, NULL, 'v'}, + {GETOPT_HELP_OPTION_DECL}, + {GETOPT_VERSION_OPTION_DECL}, + {NULL, 0, NULL, 0} +}; + +void +usage (int status) +{ + if (status != EXIT_SUCCESS) + emit_try_help (); + else + { + printf (_("\ +Usage: %s [OPTION]... [OWNER][:[GROUP]] FILE...\n\ + or: %s [OPTION]... --reference=RFILE FILE...\n\ +"), + program_name, program_name); + fputs (_("\ +Change the owner and/or group of each FILE to OWNER and/or GROUP.\n\ +With --reference, change the owner and group of each FILE to those of RFILE.\n\ +\n\ +"), stdout); + fputs (_("\ + -c, --changes like verbose but report only when a change is made\n\ + -f, --silent, --quiet suppress most error messages\n\ + -v, --verbose output a diagnostic for every file processed\n\ +"), stdout); + fputs (_("\ + --dereference affect the referent of each symbolic link (this is\n\ + the default), rather than the symbolic link itself\n\ + -h, --no-dereference affect symbolic links instead of any referenced file\n\ +"), stdout); + fputs (_("\ + (useful only on systems that can change the\n\ + ownership of a symlink)\n\ +"), stdout); + fputs (_("\ + --from=CURRENT_OWNER:CURRENT_GROUP\n\ + change the owner and/or group of each file only if\n\ + its current owner and/or group match those specified\n\ + here. Either may be omitted, in which case a match\n\ + is not required for the omitted attribute\n\ +"), stdout); + fputs (_("\ + --no-preserve-root do not treat '/' specially (the default)\n\ + --preserve-root fail to operate recursively on '/'\n\ +"), stdout); + fputs (_("\ + --reference=RFILE use RFILE's owner and group rather than\n\ + specifying OWNER:GROUP values\n\ +"), stdout); + fputs (_("\ + -R, --recursive operate on files and directories recursively\n\ +"), stdout); + fputs (_("\ +\n\ +The following options modify how a hierarchy is traversed when the -R\n\ +option is also specified. If more than one is specified, only the final\n\ +one takes effect.\n\ +\n\ + -H if a command line argument is a symbolic link\n\ + to a directory, traverse it\n\ + -L traverse every symbolic link to a directory\n\ + encountered\n\ + -P do not traverse any symbolic links (default)\n\ +\n\ +"), stdout); + fputs (HELP_OPTION_DESCRIPTION, stdout); + fputs (VERSION_OPTION_DESCRIPTION, stdout); + fputs (_("\ +\n\ +Owner is unchanged if missing. Group is unchanged if missing, but changed\n\ +to login group if implied by a ':' following a symbolic OWNER.\n\ +OWNER and GROUP may be numeric as well as symbolic.\n\ +"), stdout); + printf (_("\ +\n\ +Examples:\n\ + %s root /u Change the owner of /u to \"root\".\n\ + %s root:staff /u Likewise, but also change its group to \"staff\".\n\ + %s -hR root /u Change the owner of /u and subfiles to \"root\".\n\ +"), + program_name, program_name, program_name); + emit_ancillary_info (PROGRAM_NAME); + } + exit (status); +} + +int +main (int argc, char **argv) +{ + bool preserve_root = false; + + uid_t uid = -1; /* Specified uid; -1 if not to be changed. */ + gid_t gid = -1; /* Specified gid; -1 if not to be changed. */ + + /* Change the owner (group) of a file only if it has this uid (gid). + -1 means there's no restriction. */ + uid_t required_uid = -1; + gid_t required_gid = -1; + + /* Bit flags that control how fts works. */ + int bit_flags = FTS_PHYSICAL; + + /* 1 if --dereference, 0 if --no-dereference, -1 if neither has been + specified. */ + int dereference = -1; + + struct Chown_option chopt; + bool ok; + int optc; + + initialize_main (&argc, &argv); + set_program_name (argv[0]); + setlocale (LC_ALL, ""); + bindtextdomain (PACKAGE, LOCALEDIR); + textdomain (PACKAGE); + + atexit (close_stdout); + + chopt_init (&chopt); + + while ((optc = getopt_long (argc, argv, "HLPRcfhv", long_options, NULL)) + != -1) + { + switch (optc) + { + case 'H': /* Traverse command-line symlinks-to-directories. */ + bit_flags = FTS_COMFOLLOW | FTS_PHYSICAL; + break; + + case 'L': /* Traverse all symlinks-to-directories. */ + bit_flags = FTS_LOGICAL; + break; + + case 'P': /* Traverse no symlinks-to-directories. */ + bit_flags = FTS_PHYSICAL; + break; + + case 'h': /* --no-dereference: affect symlinks */ + dereference = 0; + break; + + case DEREFERENCE_OPTION: /* --dereference: affect the referent + of each symlink */ + dereference = 1; + break; + + case NO_PRESERVE_ROOT: + preserve_root = false; + break; + + case PRESERVE_ROOT: + preserve_root = true; + break; + + case REFERENCE_FILE_OPTION: + reference_file = optarg; + break; + + case FROM_OPTION: + { + const char *e = parse_user_spec (optarg, + &required_uid, &required_gid, + NULL, NULL); + if (e) + die (EXIT_FAILURE, 0, "%s: %s", e, quote (optarg)); + break; + } + + case 'R': + chopt.recurse = true; + break; + + case 'c': + chopt.verbosity = V_changes_only; + break; + + case 'f': + chopt.force_silent = true; + break; + + case 'v': + chopt.verbosity = V_high; + break; + + case_GETOPT_HELP_CHAR; + case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS); + default: + usage (EXIT_FAILURE); + } + } + + if (chopt.recurse) + { + if (bit_flags == FTS_PHYSICAL) + { + if (dereference == 1) + die (EXIT_FAILURE, 0, + _("-R --dereference requires either -H or -L")); + dereference = 0; + } + } + else + { + bit_flags = FTS_PHYSICAL; + } + chopt.affect_symlink_referent = (dereference != 0); + + if (argc - optind < (reference_file ? 1 : 2)) + { + if (argc <= optind) + error (0, 0, _("missing operand")); + else + error (0, 0, _("missing operand after %s"), quote (argv[argc - 1])); + usage (EXIT_FAILURE); + } + + if (reference_file) + { + struct stat ref_stats; + if (stat (reference_file, &ref_stats)) + die (EXIT_FAILURE, errno, _("failed to get attributes of %s"), + quoteaf (reference_file)); + + uid = ref_stats.st_uid; + gid = ref_stats.st_gid; + chopt.user_name = uid_to_name (ref_stats.st_uid); + chopt.group_name = gid_to_name (ref_stats.st_gid); + } + else + { + const char *e = parse_user_spec (argv[optind], &uid, &gid, + &chopt.user_name, &chopt.group_name); + if (e) + die (EXIT_FAILURE, 0, "%s: %s", e, quote (argv[optind])); + + /* If a group is specified but no user, set the user name to the + empty string so that diagnostics say "ownership :GROUP" + rather than "group GROUP". */ + if (!chopt.user_name && chopt.group_name) + chopt.user_name = xstrdup (""); + + optind++; + } + + if (chopt.recurse && preserve_root) + { + static struct dev_ino dev_ino_buf; + chopt.root_dev_ino = get_root_dev_ino (&dev_ino_buf); + if (chopt.root_dev_ino == NULL) + die (EXIT_FAILURE, errno, _("failed to get attributes of %s"), + quoteaf ("/")); + } + + bit_flags |= FTS_DEFER_STAT; + ok = chown_files (argv + optind, bit_flags, + uid, gid, + required_uid, required_gid, &chopt); + + IF_LINT (chopt_free (&chopt)); + + return ok ? EXIT_SUCCESS : EXIT_FAILURE; +} |