path: root/src/fs/gnunet-auto-share.c

/*
     This file is part of GNUnet.
     (C) 2001--2012 Christian Grothoff (and other contributing authors)

     GNUnet 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.

     GNUnet 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 GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/
/**
 * @file fs/gnunet-auto-share.c
 * @brief automatically publish files on GNUnet
 * @author Christian Grothoff
 */
#include "platform.h"
#include "gnunet_util_lib.h"


/**
 * Item in our work queue (or in the set of files/directories
 * we have successfully published).
 */
struct WorkItem
{

  /**
   * PENDING Work is kept in a linked list.
   */
  struct WorkItem *prev;

  /**
   * PENDING Work is kept in a linked list.
   */
  struct WorkItem *next;

  /**
   * Filename of the work item.
   */
  const char *filename;

  /**
   * Unique identity for this work item (used to detect
   * if we need to do the work again).
   */
  struct GNUNET_HashCode id;
};


/**
 * Global return value from 'main'.
 */
static int ret;

/**
 * Are we running 'verbosely'?
 */
static int verbose;

/**
 * Configuration to use.
 */
static const struct GNUNET_CONFIGURATION_Handle *cfg;

/**
 * Disable extractor option to use for publishing.
 */
static int disable_extractor;

/**
 * Disable creation time option to use for publishing.
 */
static int do_disable_creation_time;

/**
 * Handle for the 'shutdown' task.
 */
static GNUNET_SCHEDULER_TaskIdentifier kill_task;

/**
 * Handle for the main task that does scanning and working.
 */
static GNUNET_SCHEDULER_TaskIdentifier run_task;

/**
 * Anonymity level option to use for publishing.
 */
static unsigned int anonymity_level = 1;

/**
 * Content priority option to use for publishing.
 */
static unsigned int content_priority = 365;

/**
 * Replication level option to use for publishing.
 */
static unsigned int replication_level = 1;

/**
 * Top-level directory we monitor to auto-publish.
 */
static const char *dir_name;

/**
 * Head of linked list of files still to publish.
 */
static struct WorkItem *work_head;

/**
 * Tail of linked list of files still to publish.
 */
static struct WorkItem *work_tail;

/**
 * Map from the hash of the filename (!) to a 'struct WorkItem'
 * that was finished.
 */
static struct GNUNET_CONTAINER_MultiHashMap *work_finished;

/**
 * Set to GNUNET_YES if we are shutting down.
 */
static int do_shutdown;

/**
 * Start time of the current round; used to determine how long
 * one iteration takes (which influences how fast we schedule
 * the next one).
 */
static struct GNUNET_TIME_Absolute start_time;


/**
 * Load the set of 'work_finished' items from disk.
 */
static void
load_state ()
{
  GNUNET_break (0);
  // FIXME: implement!
}


/**
 * Save the set of 'work_finished' items on disk.
 */
static void
save_state ()
{
  GNUNET_break (0);
  // FIXME: implement!
}


/**
 * Task run on shutdown.  Serializes our current state to disk.
 *
 * @param cls closure, unused
 * @param tc scheduler context, unused
 */
static void
do_stop_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  kill_task = GNUNET_SCHEDULER_NO_TASK;
  do_shutdown = GNUNET_YES;
  if (GNUNET_SCHEDULER_NO_TASK != run_task)
  {
    GNUNET_SCHEDULER_cancel (run_task);
    run_task = GNUNET_SCHEDULER_NO_TASK;
  }
}


/**
 * Decide what the next task is (working or scanning) and schedule it.
 */
static void
schedule_next_task (void);


/**
 * Function called to process work items.
 *
 * @param cls closure, NULL
 * @param tc scheduler context (unused)
 */
static void
work (void *cls,
      const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  struct WorkItem *wi;
  struct GNUNET_HashCode key;

  run_task = GNUNET_SCHEDULER_NO_TASK;
  wi = work_head;
  GNUNET_CONTAINER_DLL_remove (work_head,
			       work_tail,
			       wi);
  // FIXME: actually run 'publish' here!

  GNUNET_CRYPTO_hash (wi->filename,
		      strlen (wi->filename),
		      &key);
  GNUNET_CONTAINER_multihashmap_put (work_finished,
				     &key,
				     wi,
				     GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
  save_state ();
  schedule_next_task ();    
}


/**
 * Recursively scan the given file/directory structure to determine
 * a unique ID that represents the current state of the hierarchy.
 *
 * @param filename file to scan
 * @param id where to store the unique ID we computed
 */
static void
determine_id (const char *filename,
	      struct GNUNET_HashCode *id)
{
  // FIXME: implement!
  GNUNET_break (0);
}


/**
 * Function called with a filename (or directory name) to publish
 * (if it has changed since the last time we published it).  This function
 * is called for the top-level files only.
 *
 * @param cls closure, NULL
 * @param filename complete filename (absolute path)
 * @return GNUNET_OK to continue to iterate, GNUNET_SYSERR during shutdown
 */
static int
add_file (void *cls,
	  const char *filename)
{
  struct WorkItem *wi;
  struct GNUNET_HashCode key;
  struct GNUNET_HashCode id;

  if (GNUNET_YES == do_shutdown)
    return GNUNET_SYSERR;
  GNUNET_CRYPTO_hash (filename,
		      strlen (filename),
		      &key);
  wi = GNUNET_CONTAINER_multihashmap_get (work_finished,
					  &key);
  memset (&id, 0, sizeof (struct GNUNET_HashCode));
  determine_id (filename, &id);
  if (NULL != wi)
  {
    if (0 == memcmp (&id,
		     &wi->id,
		     sizeof (struct GNUNET_HashCode)))
      return GNUNET_OK; /* skip: we did this one already */
    /* contents changed, need to re-do the directory... */
    GNUNET_CONTAINER_multihashmap_remove (work_finished,
					  &key,
					  wi);
    wi->id = id; 
  }
  else
  {
    wi = GNUNET_malloc (sizeof (struct WorkItem));
    wi->filename = GNUNET_strdup (filename);
  }
  GNUNET_CONTAINER_DLL_insert (work_head,
			       work_tail,
			       wi);
  if (GNUNET_YES == do_shutdown)
    return GNUNET_SYSERR; 
  return GNUNET_OK;
}


/**
 * Periodically run task to update our view of the directory to share.
 *
 * @param cls NULL
 * @param tc scheduler context, unused
 */
static void
scan (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  run_task = GNUNET_SCHEDULER_NO_TASK;
  start_time = GNUNET_TIME_absolute_get ();
  (void) GNUNET_DISK_directory_scan (dir_name,
				     &add_file,
				     NULL);
  schedule_next_task ();
}


/**
 * Decide what the next task is (working or scanning) and schedule it.
 */
static void
schedule_next_task ()
{
  struct GNUNET_TIME_Relative delay;

  if (GNUNET_YES == do_shutdown)
    return;  
  if (NULL == work_head)
  {
    /* delay by at most 4h, at least 1s, and otherwise in between depending
       on how long it took to scan */
    delay = GNUNET_TIME_absolute_get_duration (start_time);
    delay = GNUNET_TIME_relative_min (GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS,
								     4),
				      GNUNET_TIME_relative_multiply (delay,
								     100));
    delay = GNUNET_TIME_relative_max (delay,
				      GNUNET_TIME_UNIT_MINUTES);
    run_task = GNUNET_SCHEDULER_add_delayed (delay,
					     &scan,
					     NULL);
  }
  else
  {
    run_task = GNUNET_SCHEDULER_add_now (&work, NULL);
  }
}


/**
 * Main function that will be run by the scheduler.
 *
 * @param cls closure
 * @param args remaining command-line arguments
 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 * @param c configuration
 */
static void
run (void *cls, char *const *args, const char *cfgfile,
     const struct GNUNET_CONFIGURATION_Handle *c)
{
  /* check arguments */
  if ((args[0] == NULL) || (args[1] != NULL) ||
      (GNUNET_YES != GNUNET_DISK_directory_test (args[0])))
  {
    printf (_("You must specify one and only one directory name for automatic publication.\n"));
    ret = -1;
    return;
  }
  cfg = c;
  dir_name = args[0];
  work_finished = GNUNET_CONTAINER_multihashmap_create (1024);
  load_state ();
  run_task = GNUNET_SCHEDULER_add_with_priority (GNUNET_SCHEDULER_PRIORITY_IDLE,
						 &scan, NULL);
  
  kill_task =
      GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &do_stop_task,
                                    NULL);
}


/**
 * The main function to automatically publish content to GNUnet.
 *
 * @param argc number of arguments from the command line
 * @param argv command line arguments
 * @return 0 ok, 1 on error
 */
int
main (int argc, char *const *argv)
{  
  static const struct GNUNET_GETOPT_CommandLineOption options[] = {
    {'a', "anonymity", "LEVEL",
     gettext_noop ("set the desired LEVEL of sender-anonymity"),
     1, &GNUNET_GETOPT_set_uint, &anonymity_level},
    {'d', "disable-creation-time", NULL,
     gettext_noop
     ("disable adding the creation time to the metadata of the uploaded file"),
     0, &GNUNET_GETOPT_set_one, &do_disable_creation_time},
    {'D', "disable-extractor", NULL,
     gettext_noop ("do not use libextractor to add keywords or metadata"),
     0, &GNUNET_GETOPT_set_one, &disable_extractor},
    {'p', "priority", "PRIORITY",
     gettext_noop ("specify the priority of the content"),
     1, &GNUNET_GETOPT_set_uint, &content_priority},
    {'r', "replication", "LEVEL",
     gettext_noop ("set the desired replication LEVEL"),
     1, &GNUNET_GETOPT_set_uint, &replication_level},
    {'V', "verbose", NULL,
     gettext_noop ("be verbose (print progress information)"),
     0, &GNUNET_GETOPT_set_one, &verbose},
    GNUNET_GETOPT_OPTION_END
  };
  int ok;

  if (GNUNET_OK != GNUNET_STRINGS_get_utf8_args (argc, argv, &argc, &argv))
    return 2;
  ok = (GNUNET_OK ==
	GNUNET_PROGRAM_run (argc, argv, "gnunet-auto-share [OPTIONS] FILENAME",
			    gettext_noop
			    ("Automatically publish files from a directory on GNUnet"),
			    options, &run, NULL)) ? ret : 1;
  // FIXME: free memory in work lists and hash map...
  return ok;
}

/* end of gnunet-auto-share.c */