FAM_ALTBACKEND_DESC=		Alternate file monitor backend

pre-configure-FAM_ALTBACKEND-on:

	@${REINPLACE_CMD} -e 's|kqueue-helper.c|kqueue_fnm.c|g ; \

		s|.*kqueue-missing.c.*||g ; \

		s|.*dep-list.c.*||g' \

		${WRKSRC}/gio/kqueue/meson.build

	@${CP} -f ${FILESDIR}/gkqueuefilemonitor.c ${WRKSRC}/gio/kqueue/gkqueuefilemonitor.c

	@${CP} ${FILESDIR}/kqueue_fnm.c ${WRKSRC}/gio/kqueue/kqueue_fnm.c

	@${CP} ${FILESDIR}/kqueue_fnm.h ${WRKSRC}/gio/kqueue/kqueue_fnm.h

/*-

 * Copyright (c) 2016 - 2019 Rozhuk Ivan <rozhuk.im@gmail.com>

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 * Author: Rozhuk Ivan <rozhuk.im@gmail.com>

 *

 */

#include "config.h"

#include <glib-object.h>

#include <string.h>

#include <gio/gfilemonitor.h>

#include <gio/glocalfilemonitor.h>

#include <gio/giomodule.h>

#include "glib-private.h"

#include <glib-unix.h>

#include "kqueue_fnm.h"

#ifdef __clang__

#pragma clang diagnostic pop

#endif

/* Defaults. */

#ifndef KQUEUE_MON_RATE_LIMIT_TIME_INIT

#	define KQUEUE_MON_RATE_LIMIT_TIME_INIT		1000

#endif

#ifndef KQUEUE_MON_RATE_LIMIT_TIME_MAX

#	define KQUEUE_MON_RATE_LIMIT_TIME_MAX		4000

#endif

#ifndef KQUEUE_MON_RATE_LIMIT_TIME_MUL

#	define KQUEUE_MON_RATE_LIMIT_TIME_MUL		2

#endif

#ifndef KQUEUE_MON_MAX_DIR_FILES

#	define KQUEUE_MON_MAX_DIR_FILES			128

#endif

#ifndef KQUEUE_MON_LOCAL_SUBFILES

#	define KQUEUE_MON_LOCAL_SUBFILES		1

#endif

#ifndef KQUEUE_MON_LOCAL_SUBDIRS

#	define KQUEUE_MON_LOCAL_SUBDIRS			0

#endif

static GMutex			kqueue_lock;

static volatile kq_fnm_p	kqueue_fnm = NULL;

/* Exclude from file changes monitoring, watch only for dirs. */

static const char *non_local_fs[] = {

	"fusefs.sshfs",

	NULL

};

#define G_TYPE_KQUEUE_FILE_MONITOR      (g_kqueue_file_monitor_get_type())

#define G_KQUEUE_FILE_MONITOR(inst)     (G_TYPE_CHECK_INSTANCE_CAST((inst), \

					 G_TYPE_KQUEUE_FILE_MONITOR, GKqueueFileMonitor))

typedef GLocalFileMonitorClass	GKqueueFileMonitorClass;

typedef struct {

	GLocalFileMonitor	parent_instance;

	kq_fnme_p		fnme;

} GKqueueFileMonitor;

GType g_kqueue_file_monitor_get_type(void);

G_DEFINE_TYPE_WITH_CODE (GKqueueFileMonitor, g_kqueue_file_monitor, G_TYPE_LOCAL_FILE_MONITOR,

       g_io_extension_point_implement(G_LOCAL_FILE_MONITOR_EXTENSION_POINT_NAME,

               g_define_type_id,

               "kqueue",

               10))

static void

kqueue_event_handler(kq_fnm_p kfnm,

    kq_fnme_p fnme, void *udata, uint32_t event,

    const char *base, const char *filename, const char *new_filename) {

	static const uint32_t kfnm_to_glib_map[] = {

		0,				/* KF_EVENT_NOT_CHANGED */

		G_FILE_MONITOR_EVENT_CREATED,	/* KF_EVENT_CREATED */

		G_FILE_MONITOR_EVENT_DELETED,	/* KF_EVENT_DELETED */

		G_FILE_MONITOR_EVENT_RENAMED,	/* KF_EVENT_RENAMED */

		G_FILE_MONITOR_EVENT_CHANGED	/* KF_EVENT_CHANGED */

	};

	if (NULL == kfnm || NULL == filename || 0 == filename[0] ||

	    strchr(filename, '/') ||

	    KF_EVENT_CREATED > event ||

	    KF_EVENT_CHANGED < event)

		return;

	g_file_monitor_source_handle_event(udata,

	    kfnm_to_glib_map[event],

	    filename, new_filename, NULL,

	    g_get_monotonic_time());

}

static gboolean

g_kqueue_file_monitor_is_supported(void) {

	kq_file_mon_settings_t kfms;

	if (NULL != kqueue_fnm)

		return (TRUE);

	/* Init only once. */

	g_mutex_lock(&kqueue_lock);

	if (NULL != kqueue_fnm) {

		g_mutex_unlock(&kqueue_lock);

		return (TRUE); /* Initialized while wait lock. */

	}

	memset(&kfms, 0x00, sizeof(kq_file_mon_settings_t));

	kfms.rate_limit_time_init = KQUEUE_MON_RATE_LIMIT_TIME_INIT;

	kfms.rate_limit_time_max = KQUEUE_MON_RATE_LIMIT_TIME_MAX;

	kfms.rate_limit_time_mul = KQUEUE_MON_RATE_LIMIT_TIME_MUL;

	kfms.max_dir_files = KQUEUE_MON_MAX_DIR_FILES;

	kfms.mon_local_subfiles = KQUEUE_MON_LOCAL_SUBFILES;

	kfms.mon_local_subdirs = KQUEUE_MON_LOCAL_SUBDIRS;

	kfms.local_fs = NULL;

	kfms.non_local_fs = non_local_fs;

	kqueue_fnm = kq_fnm_create(&kfms, kqueue_event_handler);

	if (NULL == kqueue_fnm) {

		g_mutex_unlock(&kqueue_lock);

		return (FALSE); /* Init fail. */

	}

	g_mutex_unlock(&kqueue_lock);

	return (TRUE);

}

static gboolean

g_kqueue_file_monitor_cancel(GFileMonitor *monitor) {

	GKqueueFileMonitor *gffm = G_KQUEUE_FILE_MONITOR(monitor);

	kq_fnm_del(kqueue_fnm, gffm->fnme);

	gffm->fnme = NULL;

	return (TRUE);

}

static void

g_kqueue_file_monitor_finalize(GObject *object) {

	//GKqueueFileMonitor *gffm = G_KQUEUE_FILE_MONITOR(object);

	//g_mutex_lock(&kqueue_lock);

	//kq_fnm_free(kqueue_fnm);

	//kqueue_fnm = NULL;

	//g_mutex_unlock(&kqueue_lock);

	//G_OBJECT_CLASS(g_kqueue_file_monitor_parent_class)->finalize(object);

}

static void

g_kqueue_file_monitor_start(GLocalFileMonitor *local_monitor,

    const gchar *dirname, const gchar *basename,

    const gchar *filename, GFileMonitorSource *source) {

	GKqueueFileMonitor *gffm = G_KQUEUE_FILE_MONITOR(local_monitor);

	g_assert(NULL != kqueue_fnm);

	//g_source_ref((GSource*)source);

	if (NULL == filename) {

		filename = dirname;

	}

	gffm->fnme = kq_fnm_add(kqueue_fnm, filename, source);

}

static void

g_kqueue_file_monitor_init(GKqueueFileMonitor *monitor) {

}

static void

g_kqueue_file_monitor_class_init(GKqueueFileMonitorClass *class) {

	GObjectClass *gobject_class = G_OBJECT_CLASS(class);

	GFileMonitorClass *file_monitor_class = G_FILE_MONITOR_CLASS(class);

	class->is_supported = g_kqueue_file_monitor_is_supported;

	class->start = g_kqueue_file_monitor_start;

	class->mount_notify = TRUE; /* TODO: ??? */

	file_monitor_class->cancel = g_kqueue_file_monitor_cancel;

	gobject_class->finalize = g_kqueue_file_monitor_finalize;

}

static void

g_kqueue_file_monitor_class_finalize(GKqueueFileMonitorClass *class) {

}

void

g_io_module_load(GIOModule *module) {

	g_type_module_use(G_TYPE_MODULE(module));

	g_io_extension_point_implement(G_LOCAL_FILE_MONITOR_EXTENSION_POINT_NAME,

	    G_TYPE_KQUEUE_FILE_MONITOR, "kqueue", 10);

	g_io_extension_point_implement(G_NFS_FILE_MONITOR_EXTENSION_POINT_NAME,

	    G_TYPE_KQUEUE_FILE_MONITOR, "kqueue", 10);

}

void

g_io_module_unload(GIOModule *module) {

	g_assert_not_reached();

}

/*-

 * Copyright (c) 2016 - 2019 Rozhuk Ivan <rozhuk.im@gmail.com>

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 * Author: Rozhuk Ivan <rozhuk.im@gmail.com>

 *

 */

#include <sys/param.h>

#include <sys/types.h>

#include <sys/event.h>

#include <sys/time.h>

#include <sys/stat.h>

#include <sys/ucred.h>

#include <sys/mount.h>

#include <sys/fcntl.h> /* open, fcntl */

#include <sys/queue.h>

#include <inttypes.h>

#include <stdlib.h> /* malloc, exit */

#include <unistd.h> /* close, write, sysconf */

#include <string.h> /* bcopy, bzero, memcpy, memmove, memset, strerror... */

#include <dirent.h> /* opendir, readdir */

#include <errno.h>

#include <pthread.h>

#include <glib.h>

#include "kqueue_fnm.h"

/* Preallocate items count. */

#ifndef FILES_ALLOC_BLK_SIZE

#	define FILES_ALLOC_BLK_SIZE	32

#endif

typedef struct readdir_context_s {

	int		fd;

	uint8_t		*buf;

	size_t		buf_size;

	size_t		buf_used;

	size_t		buf_pos;

} readdir_ctx_t, *readdir_ctx_p;

typedef struct file_info_s { /* Directory file. */

	int		fd;		/* For notify kqueue(). */

	struct dirent 	de;		/* d_reclen used for action. */

	struct stat	sb;

} file_info_t, *file_info_p;

typedef struct kq_file_nonify_monitor_obj_s	*kq_fnmo_p;

typedef struct kq_file_nonify_monitor_entry_s {

	TAILQ_ENTRY(kq_file_nonify_monitor_entry_s) next;

	kq_fnmo_p	fnmo;

	void		*udata;

	volatile int	enabled;

} kq_fnme_t;

TAILQ_HEAD(kq_fnme_head, kq_file_nonify_monitor_entry_s);

typedef struct kq_file_nonify_monitor_obj_s {

	int		fd;		/* For notify kqueue(). */

	int		is_dir;

	int		is_local;	/* Is file system local. */

	int		is_removed;	/* File/dir deleted, reported and can be only free. */

	int		is_cached;	/* Added to fnmo_cache. */

	struct stat	sb;

	char		path[(PATH_MAX + sizeof(void*))];

	size_t		path_size;

	size_t		name_offset;	/* Parent path size. */

	uint32_t	rate_lim_cur_interval;	/* From rate_limit_time_init to rate_limit_time_max. 0 disabled. */

	size_t		rate_lim_ev_cnt;	/* Events count then rate_lim_cur_interval != 0 since last report. */

	sbintime_t	rate_lim_ev_last;	/* Last event time. */

	void		*udata;

	kq_fnm_p	kfnm;

	struct kq_fnme_head entry_head;

	/* For dir. */

	file_info_p	files;

	volatile size_t	files_count;

	size_t		files_allocated;

} kq_fnmo_t;

typedef struct kq_file_nonify_monitor_s {

	int		fd;		/* kqueue() fd. */

	int		pfd[2];		/* pipe queue specific. */

	GHashTable	*fnmo_cache;

	struct statfs	*mounts;

	size_t		mounts_count;

	kfnm_event_handler_cb cb_func;	/* Callback on dir/file change. */

	kq_file_mon_settings_t s;

	sbintime_t	rate_lim_time_init; /* rate_limit_time_init */

	pthread_t	tid;

} kq_fnm_t;

typedef void (*kq_msg_cb)(void *arg);

typedef struct kq_file_mon_msg_pkt_s {

	size_t		magic;

	kq_msg_cb	msg_cb;

	void		*arg;

	size_t		chk_sum;

} kq_fnm_msg_pkt_t, *kq_fnm_msg_pkt_p;

#define KF_MSG_PKT_MAGIC	0xffddaa00

#ifndef O_NOATIME

#	define O_NOATIME	0

#endif

#ifndef O_EVTONLY

#	define O_EVTONLY	O_RDONLY

#endif

#define OPEN_FILE_FLAGS		(O_EVTONLY | O_NONBLOCK | O_NOFOLLOW | O_NOATIME | O_CLOEXEC)

#ifndef NOTE_CLOSE_WRITE

#	define NOTE_CLOSE_WRITE	0

#endif

#define EVFILT_VNODE_SUB_FLAGS	(NOTE_WRITE |				\

				NOTE_EXTEND |				\

				NOTE_ATTRIB |				\

				NOTE_LINK |				\

				NOTE_CLOSE_WRITE)

#define EVFILT_VNODE_FLAGS_ALL	(NOTE_DELETE |				\

				EVFILT_VNODE_SUB_FLAGS |		\

				NOTE_RENAME |				\

				NOTE_REVOKE)

#ifndef _GENERIC_DIRSIZ

#	define _GENERIC_DIRSIZ(__de)	MIN((__de)->d_reclen, sizeof(struct dirent))

#endif

#define IS_NAME_DOTS(__name)	('.' == (__name)[0] &&			\

				 ('\0' == (__name)[1] || 		\

				  ('.' == (__name)[1] && '\0' == (__name)[2])))

#define IS_DE_NAME_EQ(__de1, __de2)  (0 == mem_cmpn((__de1)->d_name,	\

						    (__de1)->d_namlen,	\

						    (__de2)->d_name,	\

						    (__de2)->d_namlen))

#define zalloc(__size)		calloc(1, (__size))

#if (!defined(HAVE_REALLOCARRAY) && (!defined(__FreeBSD_version) || __FreeBSD_version < 1100000))

#	define reallocarray(__mem, __size, __count)	realloc((__mem), ((__size) * (__count)))

#endif

/* To not depend from compiler version. */

#define MSTOSBT(__ms)		((sbintime_t)((((uint64_t)1 << 32) * (uint64_t)(__ms)) / 1000))

#ifndef TAILQ_FOREACH_SAFE

#define	TAILQ_FOREACH_SAFE(var, head, field, tvar)			\

	for ((var) = TAILQ_FIRST((head));				\

	    (var) && ((tvar) = TAILQ_NEXT((var), field), 1);		\

	    (var) = (tvar))

#endif

#ifndef CLOCK_MONOTONIC_FAST

#	define CLOCK_MONOTONIC_FAST	CLOCK_MONOTONIC

#endif

void 	*kq_fnm_proccess_events_proc(void *data);

static inline int

mem_cmpn(const void *buf1, const size_t buf1_size,

    const void *buf2, const size_t buf2_size) {

	if (buf1_size != buf2_size)

		return (((buf1_size > buf2_size) ? 127 : -127));

	if (0 == buf1_size || buf1 == buf2)

		return (0);

	if (NULL == buf1)

		return (-127);

	if (NULL == buf2)

		return (127);

	return (memcmp(buf1, buf2, buf1_size));

}

static int

realloc_items(void **items, const size_t item_size,

    size_t *allocated, const size_t alloc_blk_cnt, const size_t count) {

	size_t allocated_prev, allocated_new;

	uint8_t *items_new;

	if (NULL == items || 0 == item_size || NULL == allocated ||

	    0 == alloc_blk_cnt)

		return (EINVAL);

	allocated_prev = (*allocated);

	if (NULL != (*items) &&

	    allocated_prev > count &&

	    allocated_prev <= (count + alloc_blk_cnt))

		return (0);

	allocated_new = (((count / alloc_blk_cnt) + 1) * alloc_blk_cnt);

	items_new = (uint8_t*)reallocarray((*items), item_size, allocated_new);

	if (NULL == items_new) /* Realloc fail! */

		return (ENOMEM);

	if (allocated_new > allocated_prev) { /* Init new mem. */

		memset((items_new + (allocated_prev * item_size)), 0x00,

		    ((allocated_new - allocated_prev) * item_size));

	}

	(*items) = items_new;

	(*allocated) = allocated_new;

	return (0);

}

/* Like getmntinfo() but allow free mem. */

static int

getmntinfo_ex(struct statfs **mntbufp, int mode) {

	int ret;

	struct statfs *buf;

	if (NULL == mntbufp)

		return (EINVAL);

	/* Request count. */

	ret = getfsstat(NULL, 0, mode);

	if (-1 == ret)

		return (ret);

	/* Alloc mem. */

	buf = calloc((ret + 1), sizeof(struct statfs));

	if (NULL == buf)

		return (-1);

	/* Request data. */

	ret = getfsstat(buf, ((ret + 1) * sizeof(struct statfs)), mode);

	if (-1 == ret) {

		free(buf);

		buf = NULL;

	}

	(*mntbufp) = buf;

	return (ret);

}

static int

mounts_find_name(struct statfs *mounts, size_t mounts_count,

    const char *mntonname) {

	size_t i;

	if (NULL == mounts || NULL == mntonname)

		return (0);

	for (i = 0; i < mounts_count; i ++) {

		if (0 != strncmp(mntonname, mounts[i].f_mntonname, MNAMELEN))

			continue;

		return (1);

	}

	return (0);

}

static int

readdir_start(int fd, struct stat *sb, size_t exp_count, readdir_ctx_p rdd) {

	size_t buf_size;

	if (-1 == fd || NULL == sb || NULL == rdd)

		return (EINVAL);

	if (-1 == lseek(fd, 0, SEEK_SET))

		return (errno);

	/* Calculate buf size for getdents(). */

	buf_size = MAX((size_t)sb->st_size, (exp_count * sizeof(struct dirent)));

	if (0 == buf_size) {

		buf_size = (16 * PAGE_SIZE);

	}

	/* Make buf size well aligned. */

	if (0 != sb->st_blksize) {

		if (powerof2(sb->st_blksize)) {

			buf_size = roundup2(buf_size, sb->st_blksize);

		} else {

			buf_size = roundup(buf_size, sb->st_blksize);

		}

	} else {

		buf_size = round_page(buf_size);

	}

	/* Init. */

	memset(rdd, 0x00, sizeof(readdir_ctx_t));

	rdd->buf = malloc(buf_size);

	if (NULL == rdd->buf)

		return (ENOMEM);

	rdd->buf_size = buf_size;

	rdd->fd = fd;

	return (0);

}

static void

readdir_free(readdir_ctx_p rdd) {

	if (NULL == rdd || NULL == rdd->buf)

		return;

	free(rdd->buf);

	memset(rdd, 0x00, sizeof(readdir_ctx_t));

}

static int

readdir_next(readdir_ctx_p rdd, struct dirent *de) {

	int error = 0;

	ssize_t ios;

	uint8_t *ptr;

	if (NULL == rdd || NULL == rdd->buf || NULL == de)

		return (EINVAL);

	for (;;) {

		if (rdd->buf_used <= rdd->buf_pos) {

			/* Called once if buf size calculated ok. */

			ios = getdents(rdd->fd, (char*)rdd->buf, rdd->buf_size);

			if (-1 == ios) {

				error = errno;

				break;

			}

			if (0 == ios) {

				error = ESPIPE; /* EOF. */

				break;

			}

			rdd->buf_used = (size_t)ios;

			rdd->buf_pos = 0;

		}

		/* Keep data aligned. */

		ptr = (rdd->buf + rdd->buf_pos);

		memcpy(de, ptr, (sizeof(struct dirent) - sizeof(de->d_name)));

		if (0 == de->d_reclen) {

			error = ESPIPE; /* EOF. */

			break;

		}

		rdd->buf_pos += de->d_reclen;

#ifdef DT_WHT

		if (DT_WHT == de->d_type)

			continue;

#endif

		if (0 == de->d_namlen)

			continue; /* Empty. */

		memcpy(de, ptr, _GENERIC_DIRSIZ(de));

		if (0 == de->d_name[0])

			continue; /* Empty. */

		if (IS_NAME_DOTS(de->d_name))

			continue; /* Dots. */

		return (0); /* OK. */

	}

	/* Err or no more files. */

	readdir_free(rdd);

	return (error);

}

static int

file_info_find_ni(file_info_p files, size_t files_count,

    file_info_p fi, size_t *idx) {

	size_t i;

	mode_t st_ftype;

	if (NULL == files || NULL == fi || NULL == idx)

		return (0);

	st_ftype = (S_IFMT & fi->sb.st_mode);

	for (i = 0; i < files_count; i ++) {

		if ((S_IFMT & files[i].sb.st_mode) != st_ftype)

			continue;

		if ((fi->sb.st_ino != files[i].sb.st_ino ||

		     fi->de.d_fileno != files[i].de.d_fileno) &&

		    0 == IS_DE_NAME_EQ(&fi->de, &files[i].de))

			continue;

		(*idx) = i;

		return (1);

	}

	(*idx) = files_count;

	return (0);

}

static int

file_info_find_ino(file_info_p files, size_t files_count,

    file_info_p fi, size_t *idx) {

	size_t i;

	mode_t st_ftype;

	if (NULL == files || NULL == fi || NULL == idx)

		return (0);

	st_ftype = (S_IFMT & fi->sb.st_mode);

	for (i = 0; i < files_count; i ++) {

		if ((S_IFMT & files[i].sb.st_mode) != st_ftype ||

		    fi->sb.st_ino != files[i].sb.st_ino ||

		    fi->de.d_fileno != files[i].de.d_fileno)

			continue;

		(*idx) = i;

		return (1);

	}

	(*idx) = files_count;

	return (0);

}

static int

file_info_find_name(file_info_p files, size_t files_count,

    file_info_p fi, size_t *idx) {

	size_t i;

	mode_t st_ftype;

	if (NULL == files || NULL == fi || NULL == idx)

		return (0);

	st_ftype = (S_IFMT & fi->sb.st_mode);

	for (i = 0; i < files_count; i ++) {

		if ((S_IFMT & files[i].sb.st_mode) != st_ftype ||

		    0 == IS_DE_NAME_EQ(&fi->de, &files[i].de))

			continue;

		(*idx) = i;

		return (1);

	}

	(*idx) = files_count;

	return (0);

}

static void

file_info_fd_close(file_info_p files, size_t files_count) {

	size_t i;

	if (NULL == files || 0 == files_count)

		return;

	for (i = 0; i < files_count; i ++) {

		if (-1 == files[i].fd)

			continue;

		close(files[i].fd);

		files[i].fd = -1;

	}

}

static int

is_fs_local(struct statfs *stfs, const char **local_fs, const char **non_local_fs) {

	size_t i;

	if (NULL == stfs)

		return (0);

	/* White listed fs. */

	if (NULL != local_fs) {

		for (i = 0; NULL != local_fs[i]; i ++) {

			if (0 == strncmp(stfs->f_fstypename, local_fs[i],

			    sizeof(stfs->f_fstypename)))

				return (1);

		}

	}

	if (0 == (MNT_LOCAL & stfs->f_flags))

		return (0);

	/* Filter out black listed fs. */

	if (NULL != non_local_fs) {

		for (i = 0; NULL != non_local_fs[i]; i ++) {

			if (0 == strncmp(stfs->f_fstypename, non_local_fs[i],

			    sizeof(stfs->f_fstypename)))

				return (0);

		}

	}

	return (1);

}

static void

kq_fnmo_rate_lim_stop(kq_fnmo_p fnmo) {

	struct kevent kev;

	if (NULL == fnmo || 0 == fnmo->rate_lim_cur_interval)

		return;

	fnmo->rate_lim_cur_interval = 0;

	fnmo->rate_lim_ev_cnt = 0;

	EV_SET(&kev, (uintptr_t)fnmo, EVFILT_TIMER,

	    (EV_DELETE | EV_CLEAR), 0, 0, NULL);

	kevent(fnmo->kfnm->fd, &kev, 1, NULL, 0, NULL);

}

static int

kq_fnmo_rate_lim_shedule_next(kq_fnmo_p fnmo) {

	u_short flags = (EV_ADD | EV_CLEAR | EV_ONESHOT);

	struct kevent kev;

	if (NULL == fnmo || -1 == fnmo->fd ||

	    0 == fnmo->kfnm->s.rate_limit_time_init)

		return (EINVAL);

	if (0 == fnmo->rate_lim_cur_interval) { /* First call. */

		fnmo->rate_lim_cur_interval = fnmo->kfnm->s.rate_limit_time_init;

	} else {

		if (fnmo->rate_lim_cur_interval == fnmo->kfnm->s.rate_limit_time_max)

			return (0); /* No need to modify timer. */

		/* Increase rate limit interval. */

		fnmo->rate_lim_cur_interval *= fnmo->kfnm->s.rate_limit_time_mul;

	}

	if (fnmo->rate_lim_cur_interval >= fnmo->kfnm->s.rate_limit_time_max) {

		/* Check upper limit and shedule periodic timer with upper rate limit time. */

		flags &= ~EV_ONESHOT;

		fnmo->rate_lim_cur_interval = fnmo->kfnm->s.rate_limit_time_max;

	}

	/* Setup timer. */

	EV_SET(&kev, (uintptr_t)fnmo, EVFILT_TIMER, flags,

	    NOTE_MSECONDS, fnmo->rate_lim_cur_interval, fnmo);

	if (-1 == kevent(fnmo->kfnm->fd, &kev, 1, NULL, 0, NULL)) {

		fnmo->rate_lim_cur_interval = 0;

		return (errno);

	}

	if (0 != (EV_ERROR & kev.flags)) {

		fnmo->rate_lim_cur_interval = 0;

		return ((int)kev.data);

	}

	return (0);

}

/* Return:

 * 0 for events that not handled

 * 1 for handled = rate limited

 * -1 on error.

 */

static int

kq_fnmo_rate_lim_check(kq_fnmo_p fnmo) {

	sbintime_t sbt, sbt_now;

	struct timespec ts;

	if (NULL == fnmo)

		return (-1);

	if (-1 == fnmo->fd ||

	    0 == fnmo->kfnm->s.rate_limit_time_init)

		return (0);

	if (0 != fnmo->rate_lim_cur_interval) {

		fnmo->rate_lim_ev_cnt ++; /* Count event, timer is active. */

		return (1);

	}

	/* Do we need to enable rate limit? */

	if (0 != clock_gettime(CLOCK_MONOTONIC_FAST, &ts))

		return (-1);

	sbt_now = tstosbt(ts);

	sbt = (fnmo->rate_lim_ev_last + fnmo->kfnm->rate_lim_time_init);

	fnmo->rate_lim_ev_last = sbt_now;

	if (sbt < sbt_now) /* Events rate to low. */

		return (0);

	/* Try to enable rate limit. */

	if (0 != kq_fnmo_rate_lim_shedule_next(fnmo))

		return (-1);

	/* Ok. */

	fnmo->rate_lim_ev_cnt ++;

	return (1);

}

static void

kq_fnmo_clean(kq_fnmo_p fnmo) {

	if (NULL == fnmo)

		return;

	kq_fnmo_rate_lim_stop(fnmo);

	if (-1 != fnmo->fd) {

		close(fnmo->fd);

		fnmo->fd = -1;

	}

	fnmo->is_removed ++;

	/* Stop monitoring files/dirs. */

	file_info_fd_close(fnmo->files, fnmo->files_count);

	free(fnmo->files);

	fnmo->files = NULL;

	fnmo->files_count = 0;

	fnmo->files_allocated = 0;

}

static void

kq_fnmo_free(kq_fnmo_p fnmo) {

	if (NULL == fnmo)

		return;

	kq_fnmo_clean(fnmo);

	if (0 != fnmo->is_cached &&

	    NULL != fnmo->kfnm &&

	    g_hash_table_lookup(fnmo->kfnm->fnmo_cache, fnmo->path) == fnmo) {

		g_hash_table_remove(fnmo->kfnm->fnmo_cache, fnmo->path);

	}

	free(fnmo);

}

static kq_fnmo_p

kq_fnmo_alloc(kq_fnm_p kfnm, const char *path, kq_fnme_p fnme) {

	kq_fnmo_p fnmo;

	if (NULL == kfnm || NULL == path)

		return (NULL);

	fnmo = zalloc(sizeof(kq_fnmo_t));

	if (NULL == fnmo)

		return (NULL);

	fnmo->fd = -1;

	/* Remember args. */

	fnmo->path_size = strlcpy(fnmo->path, path, PATH_MAX);

	/* Make sure that no trailing '/'. */

	while (1 < fnmo->path_size && '/' == fnmo->path[(fnmo->path_size - 1)]) {

		fnmo->path_size --;

		fnmo->path[fnmo->path_size] = 0;

	}

	/* Get parent folder name. */

	fnmo->name_offset = fnmo->path_size;

	while (0 < fnmo->name_offset && '/' != fnmo->path[(fnmo->name_offset - 1)]) {

		fnmo->name_offset --;

	}

	fnmo->kfnm = kfnm;

	TAILQ_INIT(&fnmo->entry_head);

	if (NULL != fnme) {

		TAILQ_INSERT_HEAD(&fnmo->entry_head, fnme, next);

	}

	return (fnmo);

}

static void

kq_fnmo_cb_func_call(kq_fnmo_p fnmo, uint32_t event,

    const char *base, const char *filename, const char *new_filename) {

	kq_fnm_p kfnm;

	kq_fnme_p fnme;

	if (NULL == fnmo)

		return;

	kfnm = fnmo->kfnm;

	TAILQ_FOREACH(fnme, &fnmo->entry_head, next) {

		if (0 == fnme->enabled) /* XXX: try lock here? */

			continue;

		kfnm->cb_func(kfnm, fnme, fnme->udata, event,

		    base, filename, new_filename);

	}

}

static int

kq_fnmo_readdir(kq_fnmo_p fnmo, size_t exp_count) {

	int error;

	struct dirent *de;

	file_info_p tmfi;

	readdir_ctx_t rdd;

	if (NULL == fnmo || -1 == fnmo->fd || 0 == fnmo->is_dir)

		return (EINVAL);

	free(fnmo->files);

	fnmo->files = NULL;

	fnmo->files_count = 0;

	fnmo->files_allocated = 0;

	/* Pre allocate. */

	if (0 != realloc_items((void**)&fnmo->files,

	    sizeof(file_info_t), &fnmo->files_allocated,

	    FILES_ALLOC_BLK_SIZE, (exp_count + 1)))

		return (ENOMEM);

	error = readdir_start(fnmo->fd, &fnmo->sb, exp_count, &rdd);

	if (0 != error)

		return (error);

	for (;;) {

		if (0 != realloc_items((void**)&fnmo->files,

		    sizeof(file_info_t), &fnmo->files_allocated,

		    FILES_ALLOC_BLK_SIZE, fnmo->files_count)) {

			free(fnmo->files);

			fnmo->files = NULL;

			fnmo->files_count = 0;

			fnmo->files_allocated = 0;

			readdir_free(&rdd);

			return (ENOMEM);

		}

		de = &fnmo->files[fnmo->files_count].de; /* Use short name. */

		/* Get file name from folder. */

		if (0 != readdir_next(&rdd, de))

			break;

		/* Get file attrs. */

		if (0 != fstatat(fnmo->fd, de->d_name,

		    &fnmo->files[fnmo->files_count].sb,

		    AT_SYMLINK_NOFOLLOW)) {

			if (ENOENT == errno)

				continue; /* File deleted. */

			memset(&fnmo->files[fnmo->files_count].sb, 0x00,

			    sizeof(struct stat));

		}

		fnmo->files[fnmo->files_count].fd = -1;

		fnmo->files_count ++;

	}

	/* Mem compact. */

	tmfi = reallocarray(fnmo->files, sizeof(file_info_t), (fnmo->files_count + 1));

	if (NULL != tmfi) { /* realloc ok. */

		fnmo->files = tmfi;

		fnmo->files_allocated = (fnmo->files_count + 1);

	}

	readdir_free(&rdd);

	return (0); /* OK. */

}

static void

kq_fnmo_fi_start(kq_fnmo_p fnmo, file_info_p fi) {

	struct kevent kev;

	if (NULL == fnmo || -1 == fnmo->fd || NULL == fi)

		return;

	fi->fd = openat(fnmo->fd, fi->de.d_name, OPEN_FILE_FLAGS);

	if (-1 == fi->fd)

		return;

	EV_SET(&kev, fi->fd, EVFILT_VNODE,

	    (EV_ADD | EV_CLEAR),

	    EVFILT_VNODE_SUB_FLAGS, 0, fnmo);

	kevent(fnmo->kfnm->fd, &kev, 1, NULL, 0, NULL);

}

static int

kq_fnmo_is_fi_monitored(kq_fnmo_p fnmo, file_info_p fi) {

	if (NULL == fnmo)

		return (0);

	if (0 == fnmo->is_local ||

	    (0 != fnmo->kfnm->s.max_dir_files &&

	     fnmo->kfnm->s.max_dir_files < fnmo->files_count))

		return (0);

	if (NULL != fi &&

	    0 == fnmo->kfnm->s.mon_local_subdirs &&

	    S_ISDIR(fi->sb.st_mode))

		return (0);

	return (1);

}

static int

kq_fnmo_reopen_fd(kq_fnmo_p fnmo) {

	int error, fd;

	struct statfs stfs;

	struct kevent kev;

	if (NULL == fnmo)

		return (EINVAL);

	/* Close fd and stop timer. */

	kq_fnmo_rate_lim_stop(fnmo);

	if (-1 != fnmo->fd) {

		close(fnmo->fd);

		fnmo->fd = -1;

	}

	fd = open(fnmo->path, OPEN_FILE_FLAGS);

	if (-1 == fd)

		return (errno);

	if (0 != fstat(fd, &fnmo->sb)) {

		error = errno;

		goto err_out;

	}

	if (0 == fnmo->sb.st_nlink) {

		error = ENOENT;

		goto err_out;

	}

	if (S_ISDIR(fnmo->sb.st_mode)) {

		fnmo->is_dir = 1;

		/* Is file system local? */

		if (0 != fnmo->kfnm->s.mon_local_subfiles &&

		    0 == fstatfs(fd, &stfs)) {

			fnmo->is_local = is_fs_local(&stfs, fnmo->kfnm->s.local_fs,

			    fnmo->kfnm->s.non_local_fs);

		}

	}

	/* Add to kqueue. */

	EV_SET(&kev, fd, EVFILT_VNODE, (EV_ADD | EV_CLEAR),

	    EVFILT_VNODE_FLAGS_ALL, 0, fnmo);

	if (-1 == kevent(fnmo->kfnm->fd, &kev, 1, NULL, 0, NULL) ||

	    0 != (EV_ERROR & kev.flags)) {

		error = errno;

		goto err_out;

	}

	fnmo->is_removed = 0;

	fnmo->fd = fd;

	return (0); /* OK. */

err_out:

	close(fd);

	return (error);

}

static int

kq_fnmo_init(kq_fnmo_p fnmo) {

	int error;

	size_t i;

	if (NULL == fnmo)

		return (EINVAL);

	error = kq_fnmo_reopen_fd(fnmo);

	if (0 != error)

		goto err_out;

	if (0 == fnmo->is_dir)

		return (0); /* OK. */

	/* Dir special processing. */

	/* Read and remember dir content. */

	error = kq_fnmo_readdir(fnmo, 0);

	if (0 != error)

		goto err_out;

	/* Add monitor sub files/dirs, ignory errors. */

	/* Check twice for performance reason. */

	if (0 != kq_fnmo_is_fi_monitored(fnmo, NULL)) {

		for (i = 0; i < fnmo->files_count; i ++) {

			if (0 != kq_fnmo_is_fi_monitored(fnmo, &fnmo->files[i])) {

				kq_fnmo_fi_start(fnmo, &fnmo->files[i]);

			}

		}

	}

	return (0); /* OK. */

err_out:

	kq_fnmo_clean(fnmo);

	return (error);

}

static void

kq_fnme_init_cb(void *arg) {

	kq_fnme_p fnme = arg;

	kq_fnmo_p fnmo;

	kq_fnm_p kfnm;

	if (NULL == fnme || NULL == fnme->fnmo)

		return;

	kfnm = fnme->fnmo->kfnm;

	/* Is in cache? */

	fnmo = g_hash_table_lookup(kfnm->fnmo_cache, fnme->fnmo->path);

	if (NULL == fnmo) {

		/* Init and add to cache. */

		g_hash_table_insert(kfnm->fnmo_cache,

		    fnme->fnmo->path, fnme->fnmo);

		fnme->fnmo->is_cached ++;

		kq_fnmo_init(fnme->fnmo);

		return;

	}

	/* Found in cache, use it. */

	TAILQ_REMOVE(&fnme->fnmo->entry_head, fnme, next);

	kq_fnmo_free(fnme->fnmo);

	fnme->fnmo = fnmo;

	TAILQ_INSERT_HEAD(&fnmo->entry_head, fnme, next);

	if (-1 == fnmo->fd) {

		/* Re init existing, no notify. */

		kq_fnmo_init(fnme->fnmo);	

	}

}

static void

kq_fnme_free(kq_fnme_p fnme) {

	if (NULL == fnme)

		return;

	if (NULL != fnme->fnmo) {

		TAILQ_REMOVE(&fnme->fnmo->entry_head, fnme, next);

		if (TAILQ_EMPTY(&fnme->fnmo->entry_head)) {

			kq_fnmo_free(fnme->fnmo);

		}

	}

	free(fnme);

}

static void

kq_fnme_free_cb(void *arg) {

	kq_fnme_free((kq_fnme_p)arg);

}

static void

kq_handle_notify_removed(kq_fnmo_p fnmo) {

	size_t i;

	if (NULL == fnmo || 0 != fnmo->is_removed)

		return;

	if (0 != fnmo->is_dir) {

		/* Notify removed files first. */

		for (i = 0; i < fnmo->files_count; i ++) {

			kq_fnmo_cb_func_call(fnmo, KF_EVENT_DELETED,

			    fnmo->path, fnmo->files[i].de.d_name, NULL);

		}

	}

	fnmo->path[fnmo->name_offset - 1] = 0;

	kq_fnmo_cb_func_call(fnmo, KF_EVENT_DELETED, fnmo->path,

	    (fnmo->path + fnmo->name_offset), NULL);

	fnmo->path[fnmo->name_offset - 1] = '/';

	kq_fnmo_clean(fnmo);

}

static void

kq_handle_changes(kq_fnmo_p fnmo) {

	size_t i, k, files_count;

	file_info_p files;

	if (NULL == fnmo || -1 == fnmo->fd)

		return;

	if (0 != fstat(fnmo->fd, &fnmo->sb) ||

	    0 == fnmo->sb.st_nlink) {

		kq_handle_notify_removed(fnmo);

		return;

	}

	if (0 == fnmo->is_dir) {

		fnmo->path[fnmo->name_offset - 1] = 0;

		kq_fnmo_cb_func_call(fnmo, KF_EVENT_CHANGED, fnmo->path,

		    (fnmo->path + fnmo->name_offset), NULL);

		fnmo->path[fnmo->name_offset - 1] = '/';

		return;

	}

	/* Dir processing. */

	/* Save prev. */

	files = fnmo->files;

	files_count = fnmo->files_count;

	fnmo->files = NULL;

	fnmo->files_count = 0;

	/* Update dir. */

	if (0 != kq_fnmo_readdir(fnmo, files_count)) {

		/* Restore prev state on fail. */

		fnmo->files = files;

		fnmo->files_count = files_count;

		return;

	}

	/* Notify removed first. */

	for (i = 0; i < files_count; i ++) {

		if (0 != file_info_find_ni(fnmo->files, fnmo->files_count,

		    &files[i], &k)) /* Deleted? */

			continue;

		if (-1 != files[i].fd) {

			close(files[i].fd);

			files[i].fd = -1;

		}

		kq_fnmo_cb_func_call(fnmo, KF_EVENT_DELETED, fnmo->path,

		    files[i].de.d_name, NULL);

	}

	/* Notify. */

	for (i = 0; i < fnmo->files_count; i ++) {

		/* Is new file/folder? */

		if (0 == file_info_find_ino(files, files_count, &fnmo->files[i], &k) &&

		    0 == file_info_find_name(files, files_count, &fnmo->files[i], &k)) { /* Add new. */

			/* Add monitor sub files/dirs, ignory errors. */

			if (0 != kq_fnmo_is_fi_monitored(fnmo, &fnmo->files[i])) {

				kq_fnmo_fi_start(fnmo, &fnmo->files[i]);

			}

			kq_fnmo_cb_func_call(fnmo, KF_EVENT_CREATED,

			    fnmo->path, fnmo->files[i].de.d_name, NULL);

			continue;

		}

		/* Keep file fd. */

		fnmo->files[i].fd = files[k].fd;

		files[k].fd = -1;

		/* Is renamed? */

		if (0 == IS_DE_NAME_EQ(&files[k].de, &fnmo->files[i].de)) {

			kq_fnmo_cb_func_call(fnmo, KF_EVENT_RENAMED,

			    fnmo->path, files[k].de.d_name,

			    fnmo->files[i].de.d_name);

			continue;

		}

		/* Is modified? */

		if (0 != memcmp(&fnmo->files[i].sb, &files[k].sb, sizeof(struct stat))) {

			kq_fnmo_cb_func_call(fnmo, KF_EVENT_CHANGED,

			    fnmo->path, fnmo->files[i].de.d_name, NULL);

			continue;

		}

		/* Not changed. */

	}

	/* Prevent FD leak die to race conditions.

	 * All fd must be -1, check this while debuging.

	 */

	file_info_fd_close(files, files_count);

	free(files);

}

static int

kq_handle_rename(kq_fnmo_p fnmo) {

	int error, up_dir_fd, found = 0;

	readdir_ctx_t rdd;

	struct dirent de;

	struct stat sb;

	char old_filename[(MAXNAMLEN + sizeof(void*))];

	size_t old_filename_size;

	if (NULL == fnmo || -1 == fnmo->fd)

		return (EINVAL);

	if (0 != fstat(fnmo->fd, &fnmo->sb) ||

	    0 == fnmo->sb.st_nlink) {

notify_removed_errno:

		error = errno;

notify_removed:

		kq_handle_notify_removed(fnmo);

		return (error);

	}

	/* Save old file name. */

	old_filename_size = (fnmo->path_size - fnmo->name_offset);

	memcpy(old_filename,

	    (fnmo->path + fnmo->name_offset),

	    old_filename_size);

	old_filename[old_filename_size] = 0;

	/* Get parent folder name. */

	fnmo->path[fnmo->name_offset] = 0;

	/* Try to open. */

	up_dir_fd = open(fnmo->path, (OPEN_FILE_FLAGS | O_DIRECTORY));

	/* Restore '/' after parent folder. */

	fnmo->path[fnmo->name_offset] = '/';

	if (-1 == up_dir_fd)

		goto notify_removed_errno;

	if (0 != fstat(up_dir_fd, &sb)) {

		close(up_dir_fd);

		goto notify_removed_errno;

	}

	error = readdir_start(up_dir_fd, &sb, 0, &rdd);

	if (0 != error) {

		close(up_dir_fd);

		goto notify_removed;

	}

	/* Find new name by inode. */

	while (0 == readdir_next(&rdd, &de)) {

		if (0 == fstatat(up_dir_fd, de.d_name, &sb, AT_SYMLINK_NOFOLLOW) &&

		    0 == memcmp(&fnmo->sb, &sb, sizeof(struct stat))) {

			found ++;

			break;

		}

	}

	close(up_dir_fd);

	if (0 == found) {

		error = ENOENT;

		goto notify_removed; /* Not found. */

	}

	/* Update name. */

	if (PATH_MAX < (fnmo->name_offset + de.d_namlen)) {

		error = EINVAL;

		goto notify_removed;

	}

	memcpy((fnmo->path + fnmo->name_offset), de.d_name, de.d_namlen);

	fnmo->path_size = (fnmo->name_offset + de.d_namlen);

	fnmo->path[fnmo->path_size] = 0;

	/* Notify. */

	kq_fnmo_cb_func_call(fnmo, KF_EVENT_RENAMED, fnmo->path,

	    old_filename, de.d_name);

	return (0);

}

static void

kq_fnm_delay_call_process(kq_fnm_p kfnm, kq_msg_cb forced_msg_cb) {

	ssize_t ios;

	kq_fnm_msg_pkt_t msg;

	for (;;) {

		ios = read(kfnm->pfd[0], &msg, sizeof(msg));

		if (0 >= ios)

			return;

		if (sizeof(msg) != ios ||

		    KF_MSG_PKT_MAGIC != msg.magic ||

		    (((size_t)msg.msg_cb) ^ ((size_t)msg.arg)) != msg.chk_sum)

			continue;

		if (NULL != forced_msg_cb) {

			forced_msg_cb(msg.arg);

			continue;

		}

		if (NULL == msg.msg_cb)

			continue;

		msg.msg_cb(msg.arg);

	}

}

static int

kq_fnm_delay_call(kq_fnm_p kfnm, kq_msg_cb msg_cb,

    void *arg) {

	kq_fnm_msg_pkt_t msg;

	if (NULL == kfnm || NULL == arg)

		return (EINVAL);

	msg.magic = KF_MSG_PKT_MAGIC;

	msg.msg_cb = msg_cb;

	msg.arg = arg;

	msg.chk_sum = (((size_t)msg.msg_cb) ^ ((size_t)msg.arg));

	if (sizeof(msg) == write(kfnm->pfd[1], &msg, sizeof(msg)))

		return (0);

	return (errno);

}

static void

kq_fnm_free_cb(void *arg) {

	kq_fnm_p kfnm = arg;

	if (NULL == kfnm)

		return;

	close(kfnm->fd);

	kfnm->fd = -1;

}

void

kq_fnm_free(kq_fnm_p kfnm) {

	GHashTableIter iter;

	gpointer key;

	kq_fnmo_p fnmo;

	kq_fnme_p fnme, fnme_temp;

	if (NULL == kfnm)

		return;

	kq_fnm_delay_call(kfnm, kq_fnm_free_cb, kfnm);

	pthread_join(kfnm->tid, NULL);

	/* Free all in delay calls queue. */

	close(kfnm->pfd[1]);

	kq_fnm_delay_call_process(kfnm, kq_fnme_free_cb);

	close(kfnm->pfd[0]);

	/* Remove all objects. */

	g_hash_table_iter_init(&iter, kfnm->fnmo_cache);

	while (g_hash_table_iter_next(&iter, &key, (gpointer)&fnmo)) {

		TAILQ_FOREACH_SAFE(fnme, &fnmo->entry_head, next, fnme_temp) {

			TAILQ_REMOVE(&fnmo->entry_head, fnme, next);

			fnme->fnmo = NULL; /* Do not free fnmo here. */

			kq_fnme_free(fnme);

		}

		g_hash_table_iter_remove(&iter); /* Remove from cache here. */

		/* Prevent remove from cache or g_hash_table_iter_next() will fail. */

		fnmo->is_cached = 0;

		kq_fnmo_free(fnmo);

	}

	g_hash_table_destroy(kfnm->fnmo_cache);

	free(kfnm->mounts);

	free(kfnm);

}

kq_fnm_p

kq_fnm_create(kq_file_mon_settings_p s, kfnm_event_handler_cb cb_func) {

	kq_fnm_p kfnm;

	struct kevent kev;

	if (NULL == s || NULL == cb_func)

		return (NULL);

	kfnm = zalloc(sizeof(kq_fnm_t));

	if (NULL == kfnm)

		return (NULL);

	kfnm->fd = kqueue();

	if (-1 == kfnm->fd)

		goto err_out;

	if (-1 == pipe2(kfnm->pfd, O_NONBLOCK))

		goto err_out;

	kfnm->fnmo_cache = g_hash_table_new(g_str_hash, g_str_equal);

	kfnm->cb_func = cb_func;

	memcpy(&kfnm->s, s, sizeof(kq_file_mon_settings_t));

	if (kfnm->s.rate_limit_time_init >= kfnm->s.rate_limit_time_max) {

		kfnm->s.rate_limit_time_max = kfnm->s.rate_limit_time_init;

	}

	if (0 == kfnm->s.rate_limit_time_mul) {

		kfnm->s.rate_limit_time_mul ++;

	}

	kfnm->rate_lim_time_init = MSTOSBT(kfnm->s.rate_limit_time_init);

	EV_SET(&kev, kfnm->pfd[0], EVFILT_READ, EV_ADD, 0, 0, NULL);

	if (-1 == kevent(kfnm->fd, &kev, 1, NULL, 0, NULL) ||

	    0 != (EV_ERROR & kev.flags))

		goto err_out;

	EV_SET(&kev, 0, EVFILT_FS, EV_ADD, 0, 0, NULL);

	if (-1 == kevent(kfnm->fd, &kev, 1, NULL, 0, NULL) ||

	    0 != (EV_ERROR & kev.flags))

		goto err_out;

	/* Get initial mounts points. */

	kfnm->mounts_count = (size_t)getmntinfo_ex(&kfnm->mounts, MNT_WAIT);

	if (0 != pthread_create(&kfnm->tid, NULL,

	    kq_fnm_proccess_events_proc, kfnm))

		goto err_out;

	return (kfnm);

err_out:

	kq_fnm_free(kfnm);

	return (NULL);

}

kq_fnme_p

kq_fnm_add(kq_fnm_p kfnm, const char *path, void *udata) {

	int error;

	kq_fnme_p fnme;

	if (NULL == kfnm || NULL == path)

		return (NULL);

	fnme = zalloc(sizeof(kq_fnme_t));

	if (NULL == fnme)

		return (NULL);

	fnme->fnmo = kq_fnmo_alloc(kfnm, path, fnme);

	if (NULL == fnme->fnmo)

		goto err_out;

	fnme->udata = udata;

	fnme->enabled = 1;

	/* Shedule delay call to init. */

	error = kq_fnm_delay_call(kfnm, kq_fnme_init_cb, fnme);

	if (0 != error) { /* Error, do no directly init to avoid freezes. */

		kq_fnmo_free(fnme->fnmo);

err_out:

		fnme->fnmo = NULL;

		kq_fnme_free(fnme);

		return (NULL);

	}

	return (fnme);

}

void

kq_fnm_del(kq_fnm_p kfnm, kq_fnme_p fnme) {

	int error;

	if (NULL == kfnm || NULL == fnme)

		return;

	/* Cancel notifications. */

	/* XXX: lock here? */

	fnme->enabled = 0;

	/* Shedule delay call to free. */

	error = kq_fnm_delay_call(kfnm, kq_fnme_free_cb, fnme);

	if (0 == error)

		return;

	/* Error, free directly. */

	kq_fnme_free(fnme);

}

static void

kq_fnm_handle_mnt_point_change(kq_fnm_p kfnm, const char *mntonname) {

	int error;

	GHashTableIter iter;

	gpointer key;

	kq_fnmo_p fnmo;

	size_t mntonname_size;

	if (NULL == kfnm || NULL == mntonname || 0 == mntonname[0])

		return;

	mntonname_size = strnlen(mntonname, MNAMELEN);

	/* Remove all objects. */

	g_hash_table_iter_init(&iter, kfnm->fnmo_cache);

	while (g_hash_table_iter_next(&iter, &key, (gpointer)&fnmo)) {

		if (NULL == fnmo || -1 == fnmo->fd) /* Do not reopen deleted. */

			continue;

		if (mntonname_size > fnmo->path_size)

			continue;

		if (0 != memcmp(fnmo->path, mntonname, mntonname_size))

			continue;

		/* Try to reopen mount point after unmount. */

		error = kq_fnmo_reopen_fd(fnmo);

		if (0 != error) {

			kq_handle_notify_removed(fnmo);

			continue;

		}

		/* Reread dir and notify about deleted and new files. */

		kq_handle_changes(fnmo);

	}

}

static void

kq_handle_mount_changes(kq_fnm_p kfnm) {

	size_t i, mounts_count;

	struct statfs *mounts;

	if (NULL == kfnm)

		return;

	/* Save prev. */

	mounts = kfnm->mounts;

	mounts_count = kfnm->mounts_count;

	kfnm->mounts = NULL;

	kfnm->mounts_count = (size_t)getmntinfo_ex(&kfnm->mounts, MNT_WAIT);

	/* Removed mounts. */

	for (i = 0; i < mounts_count; i ++) {

		if (0 != mounts_find_name(kfnm->mounts, kfnm->mounts_count,

		    mounts[i].f_mntonname))

			continue;

		kq_fnm_handle_mnt_point_change(kfnm, mounts[i].f_mntonname);

	}

	/* New mounts. */

	for (i = 0; i < kfnm->mounts_count; i ++) {

		if (0 != mounts_find_name(mounts, mounts_count,

		    kfnm->mounts[i].f_mntonname))

			continue;

		kq_fnm_handle_mnt_point_change(kfnm, kfnm->mounts[i].f_mntonname);

	}

	/* Free old mounts. */

	free(mounts);

}

static void

kq_fnm_proccess_event(kq_fnm_p kfnm, struct kevent *kev) {

	int error;

	kq_fnmo_p fnmo;

	file_info_p fi;

	size_t i;

	int is_rate_lim_checked = 0;

	struct stat sb;

	if (NULL == kfnm || NULL == kev)

		return;

	/* Handle delay calls. */

	if (kev->ident == (uintptr_t)kfnm->pfd[0]) {

		if (EVFILT_READ == kev->filter) {

			kq_fnm_delay_call_process(kfnm, NULL);

		}

		return;

	}

	/* Handle mount/unmount events. */

	if (EVFILT_FS == kev->filter) {

		kq_handle_mount_changes(kfnm);

		return;

	}

	if (0 == kev->udata)

		return; /* No associated data, skip. */

	fnmo = (kq_fnmo_p)kev->udata;

	/* FS delayed notifications. */

	if (EVFILT_TIMER == kev->filter) {

		if (0 == fnmo->rate_lim_ev_cnt) {

			/* No delayed events, disable rate limit polling. */

			kq_fnmo_rate_lim_stop(fnmo);

			return;

		}

		fnmo->rate_lim_ev_cnt = 0; /* Reset counter. */

		kq_fnmo_rate_lim_shedule_next(fnmo);

		kq_handle_changes(fnmo);

		return;

	}

	/* FS notifications. */

	if (EVFILT_VNODE != kev->filter)

		return; /* Unknown event, skip. */

	/* Subdir/file */

	if (kev->ident != (uintptr_t)fnmo->fd) {

		/* Is files changes rate limited? */

		if (1 == kq_fnmo_rate_lim_check(fnmo))

			return;

		is_rate_lim_checked ++;

		/* Try to find file and check it, without call kq_handle_changes(). */

		fi = NULL;

		for (i = 0; i < fnmo->files_count; i ++) {

			if (kev->ident != (uintptr_t)fnmo->files[i].fd)

				continue;

			fi = &fnmo->files[i];

			break;

		}

		if (NULL != fi) {

			/* Get file attrs. */

			if (0 != fstat(fi->fd, &sb)) {

				memset(&sb, 0x00, sizeof(struct stat));

			}

			/* Is modified? */

			if (0 != memcmp(&fi->sb, &sb, sizeof(struct stat))) {

				memcpy(&fi->sb, &sb, sizeof(struct stat));

				kq_fnmo_cb_func_call(fnmo, KF_EVENT_CHANGED,

				    fnmo->path, fi->de.d_name, NULL);

				return;

			}

		}

		/* fd not found or changes not found, rescan dir. */

		kev->fflags = NOTE_WRITE;

	}

	/* Monitored object. */

	/* All flags from EVFILT_VNODE_FLAGS_ALL must be handled here. */

	if (EV_ERROR & kev->flags) {

		kev->fflags |= NOTE_REVOKE; /* Treat error as unmount. */

	}

	if ((NOTE_DELETE | NOTE_REVOKE) & kev->fflags) {

		/* No ratelimit here. */

		if (0 != fnmo->is_dir) {

			/* Try to reopen mount point after unmount. */

			error = kq_fnmo_reopen_fd(fnmo);

			if (0 == error) {

				/* This will reread dir and notify about

				 * deleted and new files. */

				kq_handle_changes(fnmo);

			}

		} else {

			error = -1;

		}

		if (0 != error) {

			kq_handle_notify_removed(fnmo);

		}

		return; /* All events processed. */

	}

	if (NOTE_RENAME & kev->fflags) {

		error = kq_handle_rename(fnmo);

		if (0 != error)

			return;

	}

	if ((NOTE_WRITE | NOTE_EXTEND | NOTE_ATTRIB | NOTE_LINK | NOTE_CLOSE_WRITE) & kev->fflags) {

		if (0 == is_rate_lim_checked &&

		    1 != kq_fnmo_rate_lim_check(fnmo)) {

			kq_handle_changes(fnmo);

		}

	}

}

void *

kq_fnm_proccess_events_proc(void *data) {

	struct kevent kev;

	kq_fnm_p kfnm = data;

	if (NULL == kfnm)

		return (NULL);

	/* Get and proccess events, no wait. */

	while (0 < kevent(kfnm->fd, NULL, 0, &kev, 1, NULL)) {

		kq_fnm_proccess_event(kfnm, &kev);

	}

	return (NULL);

}

/*-

 * Copyright (c) 2016 - 2019 Rozhuk Ivan <rozhuk.im@gmail.com>

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 * Author: Rozhuk Ivan <rozhuk.im@gmail.com>

 *

 */

#ifndef __KQUEUE_FILE_NOTIFY_MONITOR_H__

#define __KQUEUE_FILE_NOTIFY_MONITOR_H__

#include <sys/param.h>

#include <sys/types.h>

#include <inttypes.h>

typedef struct kq_file_nonify_monitor_s		*kq_fnm_p;

typedef struct kq_file_nonify_monitor_entry_s	*kq_fnme_p;

typedef void (*kfnm_event_handler_cb)(kq_fnm_p kfnm,

					kq_fnme_p fnme, void *udata,

					uint32_t event,

					const char *base,

					const char *filename,

					const char *new_filename);

#define KF_EVENT_NOT_CHANGED	0 /* Internal use. */

#define KF_EVENT_CREATED	1

#define KF_EVENT_DELETED	2

#define KF_EVENT_RENAMED	3

#define KF_EVENT_CHANGED	4

typedef struct kq_file_nonify_mon_settings_s {

	uint32_t	rate_limit_time_init;	/* Fire events for dir min interval, mseconds. */

	uint32_t	rate_limit_time_max;	/* Fire events for dir max interval, mseconds. */

	uint32_t	rate_limit_time_mul;	/* Fire events time increment, mseconds. */

	size_t		max_dir_files;		/* If dir contain more than n files - do not mon files changes. */

	int		mon_local_subfiles;	/* Enable monitoring files changes on local file systems. */

	int		mon_local_subdirs;	/* Also mon for subdirs changes . */

	const char 	**local_fs;		/* NULL terminated fs names list that threat as local. Keep utill kq_fnm_free() return. */

	const char	**non_local_fs;		/* NULL terminated fs names list that threat as not local. Keep utill kq_fnm_free() return. */

} kq_file_mon_settings_t, *kq_file_mon_settings_p;

kq_fnm_p	kq_fnm_create(kq_file_mon_settings_p s,

		    kfnm_event_handler_cb cb_func);

void		kq_fnm_free(kq_fnm_p kfnm);

kq_fnme_p	kq_fnm_add(kq_fnm_p kfnm,

			    const char *path, void *udata);

void		kq_fnm_del(kq_fnm_p kfnm, kq_fnme_p fnme);

#endif /* __KQUEUE_FILE_NOTIFY_MONITOR_H__ */