// 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 "ac/dirent.h"

#include <errno.h>

#include <fcntl.h>

#include <stdlib.h>

#include <sys/stat.h>

#include <sys/types.h>

#include "ac/time.h"

#include <unistd.h>

#include "misc/itoa.h"

#include "mystring/mystring.h"

#include "config/configrc.h"

//#include "misc/debug.h"

#include "cli/cli.h"

#include "fdbuf/fdbuf.h"

#include "vcommand.h"

const char* cli_program = "vpopbull";

const char* cli_help_prefix = "Delivers pop bulletins to virtual users\n";

const char* cli_help_suffix = "";

const char* cli_args_usage = "";

const int cli_args_min = 0;

const int cli_args_max = 0;

static int o_quiet = false;

// Scans bulletin directories for any which are newer than the

// F<.timestamp> file in the specified maildir.

// For each bulletin that it finds, it adds a symlink to that bulletin to

// the specified maildir.

// Since no reformatting is done, these bulletins must be fully formatted

// email messages, including full headers.

//

// This program is designed to be run from C<checkvpw-postsetuid>.

cli_option cli_options[] = {

  { 0, "quiet", cli_option::flag, true, &o_quiet,

    "Suppress all status messages", 0 },

  {0}

};

// RETURN VALUE

//

// Exits false if an error occurred during startup, true otherwise.

// ENVIRONMENT

//

// This program expects the environment variable C<HOME> to be set, and

// executes a change directory to the contents of it before starting.

//

// This program expects C<MAILDIR> to be set, and delivers any bulletins

// that it finds into this maildir.

//

// If C<VUSER> is set, a local bulletin directory is searched as above.

// FILES

//

// The following control files are used:

//

// =over 8

//

// =item F<global-bulletin-dir>

//

// This specifies the bulletin directory for all domains.

//

// =item F<bulletin-dir>

//

// This specifies the bulletin (sub)directory for virtual domains.

//

// =back

// SEE ALSO

//

// vmailmgr(7),

// checkvpw(8),

// configuration.html

// NOTES

//

// If either the global or local bulletin directories do not exist, they

// are silently ignored without failing.

#ifndef HAVE_GETHOSTNAME

int gethostname(char *name, size_t len);

#endif

#define FATAL_FAILURES 0

#if FATAL_FAILURES

static void log(const mystring& msg)

{

  if(!o_quiet)

    ferr << "vpopbull: " msg << endl;

}

#define FAIL(X) do{ log(X); return false; }while(0)

#else

#define FAIL(X) do{ return false; }while(0)

#endif

static bool make_link(const mystring& linkname, mystring dest)

{

  char host[128];

  gethostname(host, sizeof host);

  pid_t pid = getpid();

  mystring destname;

  dest += "/";

  for(;;) {

    time_t t = time(0);

    destname = dest + itoa(t) + ".";

    destname = destname + itoa(pid) + "." + host;

    struct stat buf;

    if(stat(destname.c_str(), &buf) == -1 && errno == ENOENT)

      break;

    sleep(2);

  }

  if(symlink(linkname.c_str(), destname.c_str()) == -1)

    FAIL("Could not make symbolic link.");

  return true;

}

static bool link_file(const mystring& bulldir,

		      const mystring& filename,

		      const mystring& destdir)

{

  mystring src;

  if(bulldir[0] == '/')

    // simple symbolic link

    src = bulldir + "/" + filename;

  else {

    int i = -1;

    while((i = destdir.find_first('/', i+1)) > 0)

      src += "../";

    src = src + bulldir + filename;

  }

  return make_link(src, destdir);

}

static time_t maildir_time;

static time_t stat_mtime(const mystring& path)

{

  struct stat statbuf;

  if(stat(path.c_str(), &statbuf) == -1)

    return 0;

  else

    return statbuf.st_mtime;

}

static bool scan_file(const mystring& bulldir,

		      const mystring& filename,

		      const mystring& destdir)

{

  mystring fullname = bulldir + "/" + filename;

  time_t mtime = stat_mtime(fullname);

  if(!mtime)

    FAIL("Can't stat bulletin '" + fullname + "'.");

  if(maildir_time < mtime)

    return link_file(bulldir, filename, destdir);

  return true;

}

static bool scan_bulletins(const mystring& destdir, const mystring& bulldir)

{

  DIR* dir = opendir(bulldir.c_str());

  // Do not fail if the directory does not exist.

  if(!dir)

    FAIL("Can't open bulletin directory '" + bulldir + "'.");

  dirent* entry;

  while((entry = readdir(dir)) != 0) {

    if(entry->d_name[0] == '.')

      continue;

    if(!scan_file(bulldir, entry->d_name, destdir))

      return false;

  }

  closedir(dir);

  return true;

}

static void stat_maildir(const mystring& maildir)

{

  mystring timestamp = maildir + "/.timestamp";

  maildir_time = stat_mtime(timestamp);

  int fd = open(timestamp.c_str(), O_WRONLY | O_TRUNC | O_CREAT, 0600);

  close(fd);

}

static bool scan_bulletins(const mystring& maildir, bool non_virtual)

{

  stat_maildir(maildir);

  mystring dir = maildir + "/new";

#if FATAL_FAILURES

  return scan_bulletins(dir, config->global_bulletin_dir()) &&

    (non_virtual || scan_bulletins(dir, config->bulletin_dir()));

#else

  scan_bulletins(dir, config->global_bulletin_dir());

  if(!non_virtual)

    scan_bulletins(dir, config->bulletin_dir());

  return true;

#endif

}

int cli_main(int, char*[])

{

  if(!go_home())

    return 1;

  mystring maildir = getenv("MAILDIR");

  if(!maildir) {

    if(!o_quiet)

      ferr << "vpopbull: MAILDIR is not set." << endl;

    return 1;

  }

  mystring vuser = getenv("VUSER");

  return scan_bulletins(maildir, !vuser) ? 0 : 1;

}