poll_monitor.h

/* 
 * Copyright (C) 2014, Enrico M. Crisostomo
 *
 * 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, 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 <http://www.gnu.org/licenses/>.
 */
#ifndef FSW_POLL_MONITOR_H
#  define FSW_POLL_MONITOR_H

#  include "config.h"
#  include "monitor.h"
#  include <sys/stat.h>
#  include <ctime>
#  include "fswatch_map.h"

#  if defined HAVE_STRUCT_STAT_ST_MTIME
#    define FSW_MTIME(stat) (stat.st_mtime)
#    define FSW_CTIME(stat) (stat.st_ctime)
#  elif defined HAVE_STRUCT_STAT_ST_MTIMESPEC
#    define FSW_MTIME(stat) (stat.st_mtimespec.tv_sec)
#    define FSW_CTIME(stat) (stat.st_ctimespec.tv_sec)
#  endif

class poll_monitor : public monitor
{
public:
  poll_monitor(std::vector<std::string> paths, EVENT_CALLBACK callback);
  virtual ~poll_monitor();
  void run();

  static const unsigned int MIN_POLL_LATENCY = 1;

private:
  poll_monitor(const poll_monitor& orig);
  poll_monitor& operator=(const poll_monitor & that);

  typedef bool (poll_monitor::*poll_monitor_scan_callback)(
    const std::string &path,
    const struct stat &stat);

  typedef struct watched_file_info
  {
    time_t mtime;
    time_t ctime;
  } watched_file_info;

  typedef struct poll_monitor_data
  {
    fsw_hash_map<std::string, watched_file_info> tracked_files;
  } poll_monitor_data;

  void scan(const std::string &path, poll_monitor_scan_callback fn);
  void collect_initial_data();
  void collect_data();
  bool add_path(const std::string &path,
                const struct stat &fd_stat,
                poll_monitor_scan_callback poll_callback);
  bool initial_scan_callback(const std::string &path, const struct stat &stat);
  bool intermediate_scan_callback(const std::string &path,
                                  const struct stat &stat);
  void find_removed_files();
  void notify_events();
  void swap_data_containers();

  poll_monitor_data *previous_data;
  poll_monitor_data *new_data;

  std::vector<event> events;
  time_t curr_time;
};

#endif  /* FSW_POLL_MONITOR_H */