/* vi: set sw=4 ts=4: */
/*
 * chattr.c             - Change file attributes on an ext2 file system
 *
 * Copyright (C) 1993, 1994  Remy Card <card@masi.ibp.fr>
 *                           Laboratoire MASI, Institut Blaise Pascal
 *                           Universite Pierre et Marie Curie (Paris VI)
 *
 * This file can be redistributed under the terms of the GNU General
 * Public License
 */

/*
 * History:
 * 93/10/30     - Creation
 * 93/11/13     - Replace stat() calls by lstat() to avoid loops
 * 94/02/27     - Integrated in Ted's distribution
 * 98/12/29     - Ignore symlinks when working recursively (G M Sipe)
 * 98/12/29     - Display version info only when -V specified (G M Sipe)
 */

#include <sys/types.h>
#include <dirent.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/param.h>
#include <sys/stat.h>
#include "ext2fs/ext2_fs.h"

#ifdef __GNUC__
# define EXT2FS_ATTR(x) __attribute__(x)
#else
# define EXT2FS_ATTR(x)
#endif

#include "e2fsbb.h"
#include "e2p/e2p.h"

#define OPT_ADD 1
#define OPT_REM 2
#define OPT_SET 4
#define OPT_SET_VER 8
static int flags;
static int recursive;

static unsigned long version;

static unsigned long af;
static unsigned long rf;
static unsigned long sf;

struct flags_char {
        unsigned long flag;
        char optchar;
};

static const struct flags_char flags_array[] = {
        { EXT2_NOATIME_FL,      'A' },
        { EXT2_SYNC_FL,         'S' },
        { EXT2_DIRSYNC_FL,      'D' },
        { EXT2_APPEND_FL,       'a' },
        { EXT2_COMPR_FL,        'c' },
        { EXT2_NODUMP_FL,       'd' },
        { EXT2_IMMUTABLE_FL,    'i' },
        { EXT3_JOURNAL_DATA_FL, 'j' },
        { EXT2_SECRM_FL,        's' },
        { EXT2_UNRM_FL,         'u' },
        { EXT2_NOTAIL_FL,       't' },
        { EXT2_TOPDIR_FL,       'T' },
        { 0, 0 }
};

static unsigned long get_flag(char c)
{
        const struct flags_char *fp;
        for (fp = flags_array; fp->flag; fp++)
                if (fp->optchar == c)
                        return fp->flag;
        bb_show_usage();
        return 0;
}

static int decode_arg(char *arg)
{
        unsigned long *fl;
        char opt = *arg++;

        if (opt == '-') {
                flags |= OPT_REM;
                fl = &rf;
        } else if (opt == '+') {
                flags |= OPT_ADD;
                fl = &af;
        } else if (opt == '=') {
                flags |= OPT_SET;
                fl = &sf;
        } else
                return EOF;

        for (; *arg; ++arg)
                (*fl) |= get_flag(*arg);

        return 1;
}

static int chattr_dir_proc(const char *, struct dirent *, void *);

static void change_attributes(const char * name)
{
        unsigned long fsflags;
        struct stat st;

        if (lstat(name, &st) == -1) {
                bb_error_msg("stat %s failed", name);
                return;
        }
        if (S_ISLNK(st.st_mode) && recursive)
                return;

        /* Don't try to open device files, fifos etc.  We probably
         * ought to display an error if the file was explicitly given
         * on the command line (whether or not recursive was
         * requested).  */
        if (!S_ISREG(st.st_mode) && !S_ISLNK(st.st_mode) && !S_ISDIR(st.st_mode))
                return;

        if (flags & OPT_SET_VER)
                if (fsetversion(name, version) == -1)
                        bb_error_msg("setting version on %s", name);

        if (flags & OPT_SET) {
                fsflags = sf;
        } else {
                if (fgetflags(name, &fsflags) == -1) {
                        bb_error_msg("reading flags on %s", name);
                        goto skip_setflags;
                }
                if (flags & OPT_REM)
                        fsflags &= ~rf;
                if (flags & OPT_ADD)
                        fsflags |= af;
                if (!S_ISDIR(st.st_mode))
                        fsflags &= ~EXT2_DIRSYNC_FL;
        }
        if (fsetflags(name, fsflags) == -1)
                bb_error_msg("setting flags on %s", name);

skip_setflags:
        if (S_ISDIR(st.st_mode) && recursive)
                iterate_on_dir(name, chattr_dir_proc, NULL);
}

static int chattr_dir_proc(const char *dir_name, struct dirent *de,
                           void *private EXT2FS_ATTR((unused)))
{
        /*if (strcmp(de->d_name, ".") || strcmp(de->d_name, "..")) {*/
        if (de->d_name[0] == '.'
         && (!de->d_name[1] || (de->d_name[1] == '.' && !de->d_name[2]))
        ) {
                char *path = concat_subpath_file(dir_name, de->d_name);
                if (path) {
                        change_attributes(path);
                        free(path);
                }
        }
        return 0;
}

int chattr_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int chattr_main(int argc, char **argv)
{
        int i;
        char *arg;

        /* parse the args */
        for (i = 1; i < argc; ++i) {
                arg = argv[i];

                /* take care of -R and -v <version> */
                if (arg[0] == '-') {
                        if (arg[1] == 'R' && arg[2] == '\0') {
                                recursive = 1;
                                continue;
                        } else if (arg[1] == 'v' && arg[2] == '\0') {
                                char *tmp;
                                ++i;
                                if (i >= argc)
                                        bb_show_usage();
                                version = strtol(argv[i], &tmp, 0);
                                if (*tmp)
                                        bb_error_msg_and_die("bad version '%s'", arg);
                                flags |= OPT_SET_VER;
                                continue;
                        }
                }

                if (decode_arg(arg) == EOF)
                        break;
        }

        /* run sanity checks on all the arguments given us */
        if (i >= argc)
                bb_show_usage();
        if ((flags & OPT_SET) && ((flags & OPT_ADD) || (flags & OPT_REM)))
                bb_error_msg_and_die("= is incompatible with - and +");
        if ((rf & af) != 0)
                bb_error_msg_and_die("Can't set and unset a flag");
        if (!flags)
                bb_error_msg_and_die("Must use '-v', =, - or +");

        /* now run chattr on all the files passed to us */
        while (i < argc)
                change_attributes(argv[i++]);

        return EXIT_SUCCESS;
}