fce_api.c File Reference

File change event API for netatalk. More...

#include <arpa/inet.h>
#include <errno.h>
#include <netdb.h>
#include <netinet/in.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <time.h>
#include <unistd.h>
#include <atalk/adouble.h>
#include <atalk/afp.h>
#include <atalk/cnid.h>
#include <atalk/fce_api.h>
#include <atalk/globals.h>
#include <atalk/logger.h>
#include <atalk/unix.h>
#include <atalk/util.h>
#include <atalk/vfs.h>
#include "desktop.h"
#include "directory.h"
#include "file.h"
#include "fork.h"
#include "volume.h"
#include "fce_api_internal.h"

Macros
#define	MAXIOBUF   4096

Functions
int	afprun_bg (char *cmd)
	Run a command in the background without waiting.
void	fce_init_udp (void)
	Initialize network structs for any listeners.
void	fce_cleanup (void)
static ssize_t	build_fce_packet (const AFPObj *obj, unsigned char *iobuf, fce_ev_t event, const char *path, const char *oldpath, pid_t pid, const char *user, uint32_t event_id)
static void	send_fce_event (const AFPObj *obj, int event, const char *path, const char *oldpath)
	Send the fce information to all (connected) listeners.
static int	add_udp_socket (const char *target_ip, const char *target_port)
static void	save_close_event (const AFPObj *obj, const char *path)
static void	fce_init_ign_paths (const char *ignores, const char ***dest_array, bool is_directory)
int	fce_register (const AFPObj *obj, fce_ev_t event, const char *path, const char *oldpath)
static void	check_saved_close_events (const AFPObj *obj)
void	fce_pending_events (const AFPObj *obj)
int	fce_add_udp_socket (const char *target)
	Extern connect to afpd parameter.
int	fce_set_events (const char *events)

Variables
static struct udp_entry	udp_socket_list [FCE_MAX_UDP_SOCKS]
static int	udp_sockets = 0
static bool	udp_initialized = false
static unsigned long	fce_ev_enabled
static uint8_t	fce_ev_info
static unsigned char	iobuf [MAXIOBUF]
static const char **	skip_files
static const char **	skip_directories
static struct fce_close_event	last_close_event
static char *	fce_event_names []

Detailed Description

File change event API for netatalk.

for every detected filesystem change a UDP packet is sent to an arbitrary list of listeners. Each packet contains unix path of modified filesystem element, event reason, and a consecutive event id (32 bit). Technically we are UDP client and are sending out packets synchronuosly as they are created by the afp functions. This should not affect performance measurably. The only delaying calls occur during initialization, if we have to resolve non-IP hostnames to IP. All numeric data inside the packet is network byte order, so use ntohs / ntohl to resolve length and event id. Ideally a listener receives every packet with no gaps in event ids, starting with event id 1 and mode FCE_CONN_START followed by data events from id 2 up to 0xFFFFFFFF, followed by 0 to 0xFFFFFFFF and so on.

A gap or not starting with 1 mode FCE_CONN_START or receiving mode FCE_CONN_BROKEN means that the listener has lost at least one filesystem event

Macro Definition Documentation

MAXIOBUF

#define MAXIOBUF   4096

Function Documentation

add_udp_socket()

int add_udp_socket ( const char * target_ip, const char * target_port )

static

afprun_bg()

int afprun_bg ( char * cmd )

extern

Run a command in the background without waiting.

Note

being careful about uid/gid handling

build_fce_packet()

ssize_t build_fce_packet ( const AFPObj * obj, unsigned char * iobuf, fce_ev_t event, const char * path, const char * oldpath, pid_t pid, const char * user, uint32_t event_id )

static

Construct a UDP packet for our listeners and return packet size

check_saved_close_events()

void check_saved_close_events ( const AFPObj * obj )

static

fce_add_udp_socket()

int fce_add_udp_socket

(

const char *

target

)

Extern connect to afpd parameter.

Note

can be called multiple times for multiple listeners (up to MAX_UDP_SOCKS times)

fce_cleanup()

void fce_cleanup

(

void

)

fce_init_ign_paths()

void fce_init_ign_paths ( const char * ignores, const char *** dest_array, bool is_directory )

static

fce_init_udp()

void fce_init_udp

(

void

)

Initialize network structs for any listeners.

Note

We don't give return code because all errors are handled internally (I hope..)

fce_pending_events()

void fce_pending_events

(

const AFPObj *

obj

)

API-Calls for file change api, called from outside (file.c directory.c ofork.c filedir.c)

fce_register()

int fce_register	(	const AFPObj *	obj,
		fce_ev_t	event,
		const char *	path,
		const char *	oldpath )

Dispatcher for all incoming file change events

fce_set_events()

int fce_set_events

(

const char *

events

)

fmod,fdel,ddel,fcre,dcre

save_close_event()

void save_close_event ( const AFPObj * obj, const char * path )

static

send_fce_event()

void send_fce_event ( const AFPObj * obj, int event, const char * path, const char * oldpath )

static

Send the fce information to all (connected) listeners.

Note

We don't give return code because all errors are handled internally (I hope..)

Variable Documentation

fce_ev_enabled

unsigned long fce_ev_enabled

static

Initial value:

=
    (1 << FCE_FILE_MODIFY) |
    (1 << FCE_FILE_DELETE) |
    (1 << FCE_DIR_DELETE) |
    (1 << FCE_FILE_CREATE) |
    (1 << FCE_DIR_CREATE) |
    (1 << FCE_FILE_MOVE) |
    (1 << FCE_DIR_MOVE) |
    (1 << FCE_LOGIN) |
    (1 << FCE_LOGOUT)

fce_ev_info

uint8_t fce_ev_info

static

fce_event_names

char* fce_event_names[]

static

Initial value:

= {
    [FCE_FILE_MODIFY] = "FCE_FILE_MODIFY",
    [FCE_FILE_DELETE] = "FCE_FILE_DELETE",
    [FCE_DIR_DELETE] = "FCE_DIR_DELETE",
    [FCE_FILE_CREATE] = "FCE_FILE_CREATE",
    [FCE_DIR_CREATE] = "FCE_DIR_CREATE",
    [FCE_FILE_MOVE] = "FCE_FILE_MOVE",
    [FCE_DIR_MOVE] = "FCE_DIR_MOVE",
    [FCE_LOGIN] = "FCE_LOGIN",
    [FCE_LOGOUT] = "FCE_LOGOUT",
    [FCE_CONN_START] = "FCE_CONN_START",
    [FCE_CONN_BROKEN] = "FCE_CONN_BROKEN"
}

iobuf

unsigned char iobuf[MAXIOBUF]

static

last_close_event

struct fce_close_event last_close_event

static

skip_directories

const char** skip_directories

static

skip_files

const char** skip_files

static

udp_initialized

bool udp_initialized = false

static

udp_socket_list

struct udp_entry udp_socket_list[FCE_MAX_UDP_SOCKS]

static

udp_sockets

int udp_sockets = 0

static