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(*
* Copyright (C) 2006-2008 Vincent Hanquez <vincent@snarc.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; version 2.1 only. with the special
* exception on linking described in file LICENSE.
*
* This program 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 Lesser General Public License for more details.
*
* Inotify OCaml binding
*)
type selector =
| S_Access
| S_Attrib
| S_Close_write
| S_Close_nowrite
| S_Create
| S_Delete
| S_Delete_self
| S_Modify
| S_Move_self
| S_Moved_from
| S_Moved_to
| S_Open
| S_Dont_follow
| S_Mask_add
| S_Oneshot
| S_Onlydir
(* convenience *)
| S_Move
| S_Close
| S_All
type event_kind =
| Access
| Attrib
| Close_write
| Close_nowrite
| Create
| Delete
| Delete_self
| Modify
| Move_self
| Moved_from
| Moved_to
| Open
| Ignored
| Isdir
| Q_overflow
| Unmount
let string_of_event_kind = function
| Access -> "ACCESS"
| Attrib -> "ATTRIB"
| Close_write -> "CLOSE_WRITE"
| Close_nowrite -> "CLOSE_NOWRITE"
| Create -> "CREATE"
| Delete -> "DELETE"
| Delete_self -> "DELETE_SELF"
| Modify -> "MODIFY"
| Move_self -> "MOVE_SELF"
| Moved_from -> "MOVED_FROM"
| Moved_to -> "MOVED_TO"
| Open -> "OPEN"
| Ignored -> "IGNORED"
| Isdir -> "ISDIR"
| Q_overflow -> "Q_OVERFLOW"
| Unmount -> "UNMOUNT"
type watch = int
type event = watch * event_kind list * int32 * string option
external create : unit -> Unix.file_descr = "caml_inotify_init"
external add_watch : Unix.file_descr -> string -> selector list -> watch
= "caml_inotify_add_watch"
external rm_watch : Unix.file_descr -> watch -> unit = "caml_inotify_rm_watch"
external convert : Bytes.t -> (watch * event_kind list * int32 * int)
= "caml_inotify_convert"
external struct_size : unit -> int = "caml_inotify_struct_size"
external name_max : unit -> int = "caml_inotify_name_max"
let int_of_watch watch = watch
let watch_of_int watch = watch
let string_of_event (watch, events, cookie, name) =
Printf.sprintf "watch=%d cookie=%ld events=%s%s"
watch cookie
(String.concat "|" (List.map string_of_event_kind events))
(match name with
| None -> ""
| Some name' -> Printf.sprintf " %S" name')
let read fd =
(* Turns out that reading from blocking descriptors always requires a buffer
of the maximum size, which is, from the inotify man page:
The behavior when the buffer given to read(2) is too small to return
information about the next event depends on the kernel version: in
kernels before 2.6.21, read(2) returns 0; since kernel 2.6.21,
read(2) fails with the error EINVAL. Specifying a buffer of size
sizeof(struct inotify_event) + NAME_MAX + 1
*)
let event_size = struct_size () in
let buf_size = event_size + (name_max ()) + 1 in
let buf = Bytes.create buf_size in
let bytes_read = Unix.read fd buf 0 buf_size in
let read_c_string pos =
Bytes.sub_string buf pos ((Bytes.index_from buf pos '\x00') - pos)
in
let rec read_one pos rest =
if bytes_read < pos + event_size then rest
else
let watch, mask, cookie, len = convert (Bytes.sub buf pos event_size) in
if bytes_read < pos + event_size + len then rest
else
let name = if len > 0 then Some (read_c_string (pos + event_size)) else None in
read_one (pos + event_size + len) ((watch, mask, cookie, name) :: rest)
in
List.rev (read_one 0 [])
|
