Files
libguestfs/daemon/devsparts.ml
Richard W.M. Jones 3cea2cfe04 lib: Move guestfs_device_index impl from daemon to library.
This function doesn't work reliably with the proposed change to device
name translation.  The reason is that strings returned by
Devsparts.list_devices contained translated names, so their indexes
did not correspond to the untranslated names used outside the
appliance..

We can avoid this and make the function much simpler and faster by
implementing it on the library side instead.
2020-03-05 13:18:27 +00:00

114 lines
3.6 KiB
OCaml

(* guestfs-inspection
* Copyright (C) 2009-2019 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 Printf
open Unix
open Std_utils
open Utils
let map_block_devices ~return_md f =
let devs = Sys.readdir "/sys/block" in
let devs = Array.to_list devs in
let devs = List.filter (
fun dev ->
String.is_prefix dev "sd" ||
String.is_prefix dev "hd" ||
String.is_prefix dev "ubd" ||
String.is_prefix dev "vd" ||
String.is_prefix dev "sr" ||
(return_md && String.is_prefix dev "md" &&
String.length dev >= 3 && Char.isdigit dev.[2])
) devs in
(* Ignore the root device. *)
let devs =
List.filter (fun dev -> not (is_root_device ("/dev/" ^ dev))) devs in
(* RHBZ#514505: Some versions of qemu <= 0.10 add a
* CD-ROM device even though we didn't request it. Try to
* detect this by seeing if the device contains media.
*)
let devs =
List.filter (
fun dev ->
try
with_openfile ("/dev/" ^ dev) [O_RDONLY; O_CLOEXEC] 0
(fun _ -> true)
with _ -> false
) devs in
(* Call the map function for the devices left in the list. *)
List.map f devs
let list_devices () =
(* For backwards compatibility, don't return MD devices in the list
* returned by guestfs_list_devices. This is because most API users
* expect that this list is effectively the same as the list of
* devices added by guestfs_add_drive.
*
* Also, MD devices are special devices - unlike the devices exposed
* by QEMU, and there is a special API for them,
* guestfs_list_md_devices.
*)
let devices =
map_block_devices ~return_md:false ((^) "/dev/") in
sort_device_names devices
let rec list_partitions () =
let partitions = map_block_devices ~return_md:true add_partitions in
let partitions = List.flatten partitions in
sort_device_names partitions
and add_partitions dev =
(* Open the device's directory under /sys/block *)
let parts = Sys.readdir ("/sys/block/" ^ dev) in
let parts = Array.to_list parts in
(* Look in /sys/block/<device>/ for entries starting with
* <device>, eg. /sys/block/sda/sda1.
*)
let parts = List.filter (fun part -> String.is_prefix part dev) parts in
List.map ((^) "/dev/") parts
let nr_devices () = List.length (list_devices ())
let part_to_dev part =
let dev, part = split_device_partition part in
if part = 0 then
failwithf "device name is not a partition";
"/dev/" ^ dev
let part_to_partnum part =
let _, part = split_device_partition part in
if part = 0 then
failwithf "device name is not a partition";
part
let is_whole_device device =
(* A 'whole' block device will have a symlink to the device in its
* /sys/block directory
*)
assert (String.is_prefix device "/dev/");
let device = String.sub device 5 (String.length device - 5) in
let devpath = sprintf "/sys/block/%s/device" device in
try ignore (stat devpath); true
with Unix_error ((ENOENT|ENOTDIR), _, _) -> false