// Copyright (C) 1999,2000 Bruce Guenter <bruceg@em.ca>

//

// 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 2 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, write to the Free Software

// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

#include <config.h>

#include <stdio.h>

#include <string.h>

#include <sys/stat.h>

#include <unistd.h>

#include "misc/autodelete.h"

#include "fdbuf/fdbuf.h"

#include "mystring/mystring.h"

#include "misc/maildir.h"

#include "config/configrc.h"

#include "vpwentry/vpwentry.h"

#include "vcommand.h"

#include "misc/stat_fns.h"

#include "cli/cli.h"

#include "cdb++/cdb++.h"

const char* cli_program = "vrehash";

const char* cli_help_prefix = "Reorganize users directory\n"

"Renames user directories in a virtual domain to match the current\n"

"partitioning scheme\n";

const char* cli_help_suffix = "";

const char* cli_args_usage = "";

const int cli_args_min = 0;

const int cli_args_max = 0;

// This program is designed to be run after the sysadmin has changed the

// C<user-dir-bits> or C<user-dir-slices> configuration variables.

// It creates a new users directory called C<new.users>, where C<users>

// is the configured name of the user directory.

// It then traverses the password table, creates a new user directory name

// for each user, and moves the user's mail directory to the new

// directory name, creating any necessary directories as it goes.

// Any alias entries in the password table are copied as-is.

cli_option cli_options[] = {

  {0}

};

// RETURN VALUE

//

// Returns 1 if any part of the process fails; 0 otherwise.

// NOTES

//

// When the process is completed, a the old users directory will have

// been moved to C<backup.users>.

// If no errors occurred, you should be able to safely delete this

// directory and all its subdirectories.

// Check this directory first, though, to ensure that no important files

// remain.

// WARNINGS

//

// This program is not particularly careful to clean up after itself if

// an error occurs.

// If an error occurs, you will have to check the status of the current

// directory, the virtual password file, and all the virtual users

// subdirectories in both C<users> and C<new.users>.

static cdb_reader* in = 0;

static cdb_writer* out = 0;

static mystring cdbfilename;

static mystring tmpfilename;

static mystring newuserdir;

static mystring backupdir;

mystring lock_dir()

{

  struct stat buf;

  if(stat(".", &buf))

    return "Error stat'ing the current directory ?!?";

  if(buf.st_mode & S_ISVTX)

    return "Directory is already locked";

  if(chmod(".", buf.st_mode | S_ISVTX))

    return "Can't lock directory";

  cdbfilename = password_file + ".cdb";

  tmpfilename = cdbfilename + ".tmp";

  in = new cdb_reader(cdbfilename);

  if(!*in)

    return "Could not open virtual password table";

  out = new cdb_writer(tmpfilename, 0600);

  if(!*out)

    return "Could not open temporary table exclusively";

  return "";

}

mystring unlock_dir()

{

  struct stat buf;

  if(stat(".", &buf))

    return "Error stat'ing the current directory ?!?";

  if(!(buf.st_mode & S_ISVTX))

    return "Directory was not locked";

  if(chmod(".", buf.st_mode & ~S_ISVTX))

    return "Can't unlock directory";

  if(out) {

    if(out->end(cdbfilename)) {

      delete out;

      return "Error completing the virtual password table";

    }

    delete out;

  }

  delete in;

  return "";

}

bool getvpwent(vpwentry& vpw)

{

  autodelete<datum> d = in->nextrec();

  if(!d)

    return false;

  vpw.from_record(d->key, d->data);

  return true;

}

mystring user_dir;

mystring translate_one(vpwentry& vpw)

{

  mystring tmp = user_dir;

  mystring newdir = "./" + newuserdir +

		  domain.userdir(vpw.name).right(user_dir.length());

  mystring vpwdir = "./" + domain.userdir(vpw.name);

  mystring tmpdir = newdir.left(newdir.find_last('/'));

  if(mkdirp(tmpdir.c_str(), 0755))

    return "Error creating a user subdirectory: " + tmpdir;

  if(rename(vpw.mailbox.c_str(), newdir.c_str()))

    return "Error moving a user subdirectory." + vpw.mailbox;

  vpw.mailbox = vpwdir;

  return "";

}

mystring translate()

{

  vpwentry vpw;

  unsigned errors = 0;

  while(getvpwent(vpw)) {

    if(!!vpw.mailbox) {

      mystring response = translate_one(vpw);

      if(!!response) {

	ferr << "vrehash: " << response;

	++errors;

      }

    }

    if(!out->put(vpw.name, vpw.to_record())) {

      return "vrehash: failed to add entry to table";

      ++errors;

    }

  }

  return "";

}

mystring renamedirs()

{

  if(rename(user_dir.c_str(), backupdir.c_str()) == -1)

    return "Unable to make backup copy of user directory";

  if(rename(newuserdir.c_str(), user_dir.c_str()) == -1)

    return "Unable to rename new user directory";

#if 0

  if(rmdir(backupdir.c_str()) == -1)

    return "Unable to remove backup user directory";

#endif

  return "";

}

bool check_ok(const char* msg, mystring (*fn)())

{

  fout << "vrehash: " << msg << ": ";

  mystring status = fn();

  if(!!status) {

    fout << "failed:\n  " << status << endl;

    return false;

  }

  else {

    fout << "OK.\n";

    return true;

  }

}

int cli_main(int, char*[])

{

  if(!go_home())

    return 1;

  user_dir = config->user_dir();

  newuserdir = "new." + user_dir;

  backupdir = "backup." + user_dir;

  if(is_dir(newuserdir.c_str())) {

    ferr << "vrehash: error: new users directory '" << newuserdir

	 << "' already exists.\n";

    return 1;

  }

  if(is_dir(backupdir.c_str())) {

    ferr << "vrehash: error: backup directory '" << backupdir

	 << "' already exists.\n";

    return 1;

  }

  if(!check_ok("locking directory", lock_dir))

    return 1;

  if(!check_ok("translating paths and making directories", translate))

    return 1;

  if(!check_ok("removing old user directory", renamedirs))

    return 1;

  if(!check_ok("unlocking directory", unlock_dir))

    return 1;

  return 0;

}