transmission/daemon/watch.c

278 lines
6.5 KiB
C

/*
* This file Copyright (C) Mnemosyne LLC
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
*
* $Id$
*/
#ifdef WITH_INOTIFY
#include <sys/inotify.h>
#include <sys/select.h>
#include <unistd.h> /* close */
#else
#include <sys/types.h> /* stat */
#include <sys/stat.h> /* stat */
#include <event2/buffer.h> /* evbuffer */
#endif
#include <errno.h>
#include <string.h> /* strlen () */
#include <stdio.h> /* perror () */
#include <dirent.h> /* readdir */
#include <libtransmission/transmission.h>
#include <libtransmission/log.h>
#include <libtransmission/utils.h> /* tr_buildPath (), tr_logAddInfo () */
#include "watch.h"
struct dtr_watchdir
{
tr_session * session;
char * dir;
dtr_watchdir_callback * callback;
#ifdef WITH_INOTIFY
int inotify_fd;
#else /* readdir implementation */
time_t lastTimeChecked;
struct evbuffer * lastFiles;
#endif
};
/***
**** INOTIFY IMPLEMENTATION
***/
#if defined (WITH_INOTIFY)
/* how many inotify events to try to batch into a single read */
#define EVENT_BATCH_COUNT 50
/* size of the event structure, not counting name */
#define EVENT_SIZE (sizeof (struct inotify_event))
/* reasonable guess as to size of 50 events */
#define BUF_LEN (EVENT_BATCH_COUNT * (EVENT_SIZE + 16) + 2048)
#define DTR_INOTIFY_MASK (IN_CLOSE_WRITE|IN_MOVED_TO|IN_CREATE|IN_ONLYDIR)
static void
watchdir_new_impl (dtr_watchdir * w)
{
int i;
DIR * odir;
w->inotify_fd = inotify_init ();
if (w->inotify_fd < 0)
{
i = -1;
}
else
{
tr_logAddInfo ("Using inotify to watch directory \"%s\"", w->dir);
i = inotify_add_watch (w->inotify_fd, w->dir, DTR_INOTIFY_MASK);
}
if (i < 0)
{
tr_logAddError ("Unable to watch \"%s\": %s", w->dir, tr_strerror (errno));
}
else if ((odir = opendir (w->dir)))
{
struct dirent * d;
while ((d = readdir (odir)))
{
const char * name = d->d_name;
if (!tr_str_has_suffix (name, ".torrent")) /* skip non-torrents */
continue;
tr_logAddInfo ("Found new .torrent file \"%s\" in watchdir \"%s\"", name, w->dir);
w->callback (w->session, w->dir, name);
}
closedir (odir);
}
}
static void
watchdir_free_impl (dtr_watchdir * w)
{
if (w->inotify_fd >= 0)
{
inotify_rm_watch (w->inotify_fd, DTR_INOTIFY_MASK);
close (w->inotify_fd);
}
}
static void
watchdir_update_impl (dtr_watchdir * w)
{
int ret;
fd_set rfds;
struct timeval time;
const int fd = w->inotify_fd;
/* timeout after one second */
time.tv_sec = 1;
time.tv_usec = 0;
/* make the fd_set hold the inotify fd */
FD_ZERO (&rfds);
FD_SET (fd, &rfds);
/* check for added files */
ret = select (fd+1, &rfds, NULL, NULL, &time);
if (ret < 0) {
perror ("select");
} else if (!ret) {
/* timed out! */
} else if (FD_ISSET (fd, &rfds)) {
int i = 0;
char buf[BUF_LEN];
int len = read (fd, buf, sizeof (buf));
while (i < len) {
struct inotify_event * event = (struct inotify_event *) &buf[i];
const char * name = event->name;
if (tr_str_has_suffix (name, ".torrent"))
{
tr_logAddInfo ("Found new .torrent file \"%s\" in watchdir \"%s\"", name, w->dir);
w->callback (w->session, w->dir, name);
}
i += EVENT_SIZE + event->len;
}
}
}
#else /* WITH_INOTIFY */
/***
**** READDIR IMPLEMENTATION
***/
#define WATCHDIR_POLL_INTERVAL_SECS 10
#define FILE_DELIMITER '\t'
static void
watchdir_new_impl (dtr_watchdir * w UNUSED)
{
tr_logAddInfo ("Using readdir to watch directory \"%s\"", w->dir);
w->lastFiles = evbuffer_new ();
}
static void
watchdir_free_impl (dtr_watchdir * w)
{
evbuffer_free (w->lastFiles);
}
static char*
get_key_from_file (const char * filename, const size_t len)
{
return tr_strdup_printf ("%c%*.*s%d", FILE_DELIMITER, (int)len, (int)len, filename, FILE_DELIMITER);
}
static void
add_file_to_list (struct evbuffer * buf, const char * filename, size_t len)
{
char * key = get_key_from_file (filename, len);
evbuffer_add (buf, key, strlen (key));
tr_free (key);
}
static bool
is_file_in_list (struct evbuffer * buf, const char * filename, size_t len)
{
bool in_list;
struct evbuffer_ptr ptr;
char * key = get_key_from_file (filename, len);
ptr = evbuffer_search (buf, key, strlen (key), NULL);
in_list = ptr.pos != -1;
tr_free (key);
return in_list;
}
static void
watchdir_update_impl (dtr_watchdir * w)
{
struct stat sb;
DIR * odir;
const time_t oldTime = w->lastTimeChecked;
const char * dirname = w->dir;
struct evbuffer * curFiles = evbuffer_new ();
if ((oldTime + WATCHDIR_POLL_INTERVAL_SECS < time (NULL))
&& !stat (dirname, &sb)
&& S_ISDIR (sb.st_mode)
&& ((odir = opendir (dirname))))
{
struct dirent * d;
for (d = readdir (odir); d != NULL; d = readdir (odir))
{
size_t len;
const char * name = d->d_name;
if (!name || *name=='.') /* skip dotfiles */
continue;
if (!tr_str_has_suffix (name, ".torrent")) /* skip non-torrents */
continue;
len = strlen (name);
add_file_to_list (curFiles, name, len);
/* if this file wasn't here last time, try adding it */
if (!is_file_in_list (w->lastFiles, name, len)) {
tr_logAddInfo ("Found new .torrent file \"%s\" in watchdir \"%s\"", name, w->dir);
w->callback (w->session, w->dir, name);
}
}
closedir (odir);
w->lastTimeChecked = time (NULL);
evbuffer_free (w->lastFiles);
w->lastFiles = curFiles;
}
}
#endif
/***
****
***/
dtr_watchdir*
dtr_watchdir_new (tr_session * session, const char * dir, dtr_watchdir_callback * callback)
{
dtr_watchdir * w = tr_new0 (dtr_watchdir, 1);
w->session = session;
w->dir = tr_strdup (dir);
w->callback = callback;
watchdir_new_impl (w);
return w;
}
void
dtr_watchdir_update (dtr_watchdir * w)
{
if (w != NULL)
watchdir_update_impl (w);
}
void
dtr_watchdir_free (dtr_watchdir * w)
{
if (w != NULL)
{
watchdir_free_impl (w);
tr_free (w->dir);
tr_free (w);
}
}