(* Guestfs Browser.
* Copyright (C) 2010-2011 Red Hat Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*)
open ExtList
open ExtString
open Utils
open Slave_types
open Slave_utils
open Printf
module C = Libvirt.Connect
module Cond = Condition
module D = Libvirt.Domain
module G = Guestfs
module M = Mutex
module Q = Queue
module UTF8 = CamomileLibraryDefault.Camomile.UTF8
type 'a callback = 'a -> unit
(* The commands. *)
type command =
| Exit_thread
| Checksum_file of source * string * string * string callback
| Connect of string option * domain list callback
| Disk_usage of source * string * int64 callback
| Download_dir_find0 of source * string * string * unit callback
| Download_dir_tarball of source * string * download_dir_tarball_format * string * unit callback
| Download_file of source * string * string * bool * unit callback
| File_information of source * string * string callback
| List_applications of inspection_os * G.application array callback
| Open_domain of string * inspection_data callback
| Open_images of (string * string option) list * inspection_data callback
| Read_directory of source * string * direntry list callback
| Reopen of inspection_data callback
| Run_command of string * unit callback
let rec string_of_command = function
| Exit_thread -> "Exit_thread"
| Checksum_file (src, pathname, csumtype, _) ->
sprintf "Checksum_file (%s, %s, %s)"
(string_of_source src) pathname csumtype
| Connect (Some name, _) -> sprintf "Connect %s" name
| Connect (None, _) -> "Connect NULL"
| Disk_usage (src, remotedir, _) ->
sprintf "Disk_usage (%s, %s)" (string_of_source src) remotedir
| Download_dir_find0 (src, remotedir, localfile, _) ->
sprintf "Download_dir_find0 (%s, %s, %s)"
(string_of_source src) remotedir localfile
| Download_dir_tarball (src, remotedir, format, localfile, _) ->
sprintf "Download_dir_tarball (%s, %s, %s, %s)"
(string_of_source src) remotedir
(string_of_download_dir_tarball_format format) localfile
| Download_file (src, remotefile, localfile, check, _) ->
sprintf "Download_file (%s, %s, %s, %b)"
(string_of_source src) remotefile localfile check
| File_information (src, pathname, _) ->
sprintf "File_information (%s, %s)" (string_of_source src) pathname
| List_applications (os, _) ->
sprintf "List_applications %s" os.insp_root
| Open_domain (name, _) -> sprintf "Open_domain %s" name
| Open_images (images, _) ->
sprintf "Open_images %s" (string_of_images images)
| Read_directory (src, dir, _) ->
sprintf "Read_directory (%s, %s)" (string_of_source src) dir
| Reopen _ ->
"Reopen"
| Run_command (cmd, _) ->
sprintf "Run_command %s" cmd
and string_of_images images =
"[" ^
String.concat "; "
(List.map (function
| fn, None -> fn
| fn, Some format -> sprintf "%s (%s)" fn format)
images) ^ "]"
and string_of_source = function
| OS { insp_root = root } ->
sprintf "OS %s" root
| Volume dev ->
sprintf "Volume %s" dev
and string_of_download_dir_tarball_format = function
| Tar -> "Tar"
| TGZ -> "TGZ"
| TXZ -> "TXZ"
let no_callback _ = ()
let failure_hook = ref (fun _ -> ())
let busy_hook = ref (fun _ -> ())
let idle_hook = ref (fun _ -> ())
let status_hook = ref (fun _ -> ())
let progress_hook = ref (fun _ -> ())
let set_failure_hook cb = failure_hook := cb
let set_busy_hook cb = busy_hook := cb
let set_idle_hook cb = idle_hook := cb
let set_status_hook cb = status_hook := cb
let set_progress_hook cb = progress_hook := cb
(* Execute a function, while holding a mutex. If the function
* fails, ensure we release the mutex before rethrowing the
* exception.
*)
let with_lock m f =
M.lock m;
let r = try Left (f ()) with exn -> Right exn in
M.unlock m;
match r with
| Left r -> r
| Right exn -> raise exn
(* The queue of commands, and a lock and condition to protect it. *)
let q = Q.create ()
let q_discard = ref false
let q_lock = M.create ()
let q_cond = Cond.create ()
(* Send a command message to the slave thread. *)
let send_to_slave ?fail cmd =
debug "sending message %s to slave thread ..." (string_of_command cmd);
with_lock q_lock (
fun () ->
Q.push (fail, cmd) q;
Cond.signal q_cond
)
let discard_command_queue () =
with_lock q_lock (
fun () ->
Q.clear q;
(* Discard the currently running command. *)
q_discard := true
)
let checksum_file ?fail src pathname csumtype cb =
send_to_slave ?fail (Checksum_file (src, pathname, csumtype, cb))
let connect ?fail uri cb = send_to_slave ?fail (Connect (uri, cb))
let disk_usage ?fail src remotedir cb =
send_to_slave ?fail (Disk_usage (src, remotedir, cb))
let download_dir_find0 ?fail src remotedir localfile cb =
send_to_slave ?fail (Download_dir_find0 (src, remotedir, localfile, cb))
let download_dir_tarball ?fail src remotedir format localfile cb =
send_to_slave ?fail
(Download_dir_tarball (src, remotedir, format, localfile, cb))
let download_file ?fail src remotefile localfile cb =
send_to_slave ?fail (Download_file (src, remotefile, localfile, false, cb))
let download_file_if_not_exist ?fail src remotefile localfile cb =
send_to_slave ?fail (Download_file (src, remotefile, localfile, true, cb))
let file_information ?fail src pathname cb =
send_to_slave ?fail (File_information (src, pathname, cb))
let list_applications ?fail os cb =
send_to_slave ?fail (List_applications (os, cb))
let open_domain ?fail name cb = send_to_slave ?fail (Open_domain (name, cb))
let open_images ?fail images cb = send_to_slave ?fail (Open_images (images, cb))
let read_directory ?fail src path cb =
send_to_slave ?fail (Read_directory (src, path, cb))
let reopen ?fail cb =
send_to_slave ?fail (Reopen cb)
let run_command ?fail cmd cb =
send_to_slave ?fail (Run_command (cmd, cb))
(*----- Slave thread starts here -----*)
(* Set this to true to exit the thread. *)
let quit = ref false
(* Handles. These are not protected by locks because only the slave
* thread has access to them.
*)
let conn = ref None
let g = ref None
(* Last Open_domain or Open_images command. This is so we can implement
* the Reopen command.
*)
let last_open = ref None
(* Run the callback unless someone set the q_discard flag while
* we were running the command.
*)
let callback_if_not_discarded (cb : 'a callback) (arg : 'a) =
let discard = with_lock q_lock (fun () -> !q_discard) in
if not discard then
GtkThread.async cb arg
(* Update the status bar. *)
let status fs =
let f str = GtkThread.async !status_hook str in
ksprintf f fs
let rec loop () =
debug "top of slave loop";
(* Get the next command. *)
let fail, cmd =
with_lock q_lock (
fun () ->
while Q.is_empty q do Cond.wait q_cond q_lock done;
q_discard := false;
Q.pop q
) in
debug "slave processing command %s ..." (string_of_command cmd);
(try
GtkThread.async !busy_hook ();
execute_command cmd
with exn ->
(* If the user provided an override ?fail parameter to the
* original call, call that, else call the global hook.
*)
match fail with
| Some cb -> GtkThread.async cb exn
| None -> GtkThread.async !failure_hook exn
);
(* If there are no more commands in the queue, run the idle hook. *)
let empty = with_lock q_lock (fun () -> Q.is_empty q) in
if empty then GtkThread.async !idle_hook ();
if !quit then Thread.exit ();
loop ()
and execute_command = function
| Exit_thread ->
quit := true;
close_all ()
| Checksum_file (src, pathname, csumtype, cb) ->
status "Calculating %s checksum of %s ..." csumtype pathname;
let g = get_g () in
let r =
with_mount_ro g src (
fun () ->
g#checksum csumtype pathname
) in
status "Finished calculating %s checksum of %s" csumtype pathname;
callback_if_not_discarded cb r
| Connect (name, cb) ->
let printable_name =
match name with None -> "default hypervisor" | Some uri -> uri in
status "Connecting to %s ..." printable_name;
close_all ();
conn := Some (C.connect_readonly ?name ());
let conn = get_conn () in
let doms = D.get_domains conn [D.ListAll] in
let doms = List.map (
fun d ->
{ dom_id = D.get_id d;
dom_name = D.get_name d;
dom_state = (D.get_info d).D.state }
) doms in
let cmp { dom_name = n1 } { dom_name = n2 } = UTF8.compare n1 n2 in
let doms = List.sort ~cmp doms in
status "Connected to %s" printable_name;
callback_if_not_discarded cb doms
| Disk_usage (src, remotedir, cb) ->
status "Calculating disk usage of %s ..." remotedir;
let g = get_g () in
let r =
with_mount_ro g src (
fun () ->
g#du remotedir
) in
status "Finished calculating disk usage of %s" remotedir;
callback_if_not_discarded cb r
| Download_dir_find0 (src, remotedir, localfile, cb) ->
status "Downloading %s filenames to %s ..." remotedir localfile;
let g = get_g () in
with_mount_ro g src (
fun () ->
g#find0 remotedir localfile
);
status "Finished downloading %s" localfile;
callback_if_not_discarded cb ()
| Download_dir_tarball (src, remotedir, format, localfile, cb) ->
status "Downloading %s to %s ..." remotedir localfile;
let g = get_g () in
let f = match format with
| Tar -> g#tar_out
| TGZ -> g#tgz_out
| TXZ -> g#txz_out
in
with_mount_ro g src (
fun () ->
f remotedir localfile
);
status "Finished downloading %s" localfile;
callback_if_not_discarded cb ()
| Download_file (src, remotefile, localfile, check, cb) ->
if not check || not (local_file_exists localfile) then (
status "Downloading %s to %s ..." remotefile localfile;
let g = get_g () in
with_mount_ro g src (
fun () ->
g#download remotefile localfile
);
status "Finished downloading %s" localfile
);
callback_if_not_discarded cb ()
| File_information (src, pathname, cb) ->
status "Calculating file information for %s ..." pathname;
let g = get_g () in
let r =
with_mount_ro g src (
fun () ->
g#file pathname
) in
status "Finished calculating file information for %s" pathname;
callback_if_not_discarded cb r
| List_applications (os, cb) ->
status "Listing applications ...";
let g = get_g () in
let r =
with_mount_ro g (OS os) (
fun () ->
g#inspect_list_applications os.insp_root
) in
status "Finished listing applications";
callback_if_not_discarded cb r
| Open_domain (name, cb) as cmd ->
status "Opening %s ..." name;
let conn = get_conn () in
let dom = D.lookup_by_name conn name in
let xml = D.get_xml_desc dom in
let images = get_disk_images_from_xml xml in
open_disk_images images cb cmd
| Open_images (images, cb) as cmd ->
status "Opening disk images ...";
open_disk_images images cb cmd
| Read_directory (src, dir, cb) ->
status "Reading directory %s ..." dir;
let g = get_g () in
let names, stats, links =
with_mount_ro g src (
fun () ->
let names = g#ls dir in (* sorted and without . and .. *)
let stats = lstatlist g dir names in
let links = readlinks g dir names (Array.of_list stats) in
Array.to_list names, stats, links
) in
assert (
let n = List.length names in
n = List.length stats && n = List.length links
);
let entries = List.combine (List.combine names stats) links in
let entries = List.map (
fun ((name, stat), link) ->
{ dent_name = name; dent_stat = stat; dent_link = link }
) entries in
status "Finished reading directory %s" dir;
callback_if_not_discarded cb entries
| Reopen cb ->
(* Execute the last_open command, if there was one. But note
* that we have to replace the callback in the saved command with
* the new callback passed by the main thread to reopen.
*)
(match !last_open with
| Some (Open_domain (name, _)) ->
execute_command (Open_domain (name, cb))
| Some (Open_images (images, _)) ->
execute_command (Open_images (images, cb))
| None ->
() (* invalid_arg? *)
| _ ->
assert false (* should never happen *)
)
| Run_command (cmd, cb) ->
status "Running %s ..." cmd;
if Sys.command cmd <> 0 then
failwith "External command failed: %s" cmd;
status "Finished %s ..." cmd;
callback_if_not_discarded cb ()
(* Expect to be connected, and return the current libvirt connection. *)
and get_conn () =
match !conn with
| Some conn -> conn
| None -> failwith "not connected to libvirt"
and get_g () =
match !g with
| Some g -> g
| None -> failwith "no domain or disk image is open"
(* Close all libvirt and libguestfs handles. *)
and close_all () =
(match !conn with Some conn -> C.close conn | None -> ());
conn := None;
last_open := None;
close_g ()
and close_g () =
(match !g with Some g -> g#close () | None -> ());
g := None
and get_disk_images_from_xml xml =
let xml = Xml.parse_string xml in
(* Return the device nodes. *)
let devices =
match xml with
| Xml.Element ("domain", _, children) ->
let devices =
List.filter_map (
function
| Xml.Element ("devices", _, devices) -> Some devices
| _ -> None
) children in
List.concat devices
| _ ->
failwith "get_xml_desc didn't return " in
(* Look for