busybox

/* vi: set sw=4 ts=4: */

/*

 * simple inotify daemon

 * reports filesystem changes via userspace agent

 *

 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>

 *

 * Licensed under GPLv2, see file LICENSE in this tarball for details.

 */

​

/*

 * Use as follows:

 * # inotifyd /user/space/agent dir/or/file/being/watched[:mask] ...

 *

 * When a filesystem event matching the specified mask is occured on specified file (or directory)

 * a userspace agent is spawned and given the following parameters:

 * $1. actual event(s)

 * $2. file (or directory) name

 * $3. name of subfile (if any), in case of watching a directory

 *

 * E.g. inotifyd ./dev-watcher /dev:n

 *

 * ./dev-watcher can be, say:

 * #!/bin/sh

 * echo "We have new device in here! Hello, $3!"

 *

 * See below for mask names explanation.

 */

​

#include "libbb.h"

#include <sys/inotify.h>

​

static const char mask_names[] ALIGN1 =

    "a" // 0x00000001   File was accessed

    "c" // 0x00000002   File was modified

    "e" // 0x00000004   Metadata changed

    "w" // 0x00000008   Writtable file was closed

    "0" // 0x00000010   Unwrittable file closed

    "r" // 0x00000020   File was opened

    "m" // 0x00000040   File was moved from X

    "y" // 0x00000080   File was moved to Y

    "n" // 0x00000100   Subfile was created

    "d" // 0x00000200   Subfile was deleted

    "D" // 0x00000400   Self was deleted

    "M" // 0x00000800   Self was moved

;

​

extern int inotify_init(void);

extern int inotify_add_watch(int fd, const char *path, uint32_t mask);

​

int inotifyd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;

int inotifyd_main(int argc UNUSED_PARAM, char **argv)

{

    unsigned mask = IN_ALL_EVENTS; // assume we want all events

    struct pollfd pfd;

    char **watched = ++argv; // watched name list

    const char *args[] = { *argv, NULL, NULL, NULL, NULL };

​

    // sanity check: agent and at least one watch must be given

    if (!argv[1])

        bb_show_usage();

​

    // open inotify