[Libguestfs] [v2v PATCH 2/2] Consolidate handling of temporary files/dirs
Pino Toscano
ptoscano at redhat.com
Mon Apr 6 15:40:45 UTC 2020
Create two temporary directories for all the files created during the
virt-v2v run:
1) tmpdir, created as $TMPDIR/virt-v2v.XXXXXX, for all the small files
2) cachedir, created as $LIBGUESTFS_CACHEDIR/virt-v2v.XXXXXX, for the
big files (e.g. disks)
This way there is no need to manually schedule all the temporary files
and directories for removal when the application quits.
---
v2v/input_ova.ml | 5 ++---
v2v/input_vmx.ml | 5 -----
v2v/measure_disk.ml | 5 +++--
v2v/output_glance.ml | 18 ++++++------------
v2v/output_libvirt.ml | 3 +++
v2v/output_null.ml | 14 ++------------
v2v/output_openstack.ml | 3 +--
v2v/output_rhv.ml | 2 +-
v2v/output_rhv_upload.ml | 7 -------
v2v/parse_ova.ml | 30 ++++++++++++++----------------
v2v/utils.ml | 25 +++++++++++++++++++++++--
v2v/utils.mli | 7 +++++++
v2v/v2v.ml | 15 ++++++---------
13 files changed, 68 insertions(+), 71 deletions(-)
diff --git a/v2v/input_ova.ml b/v2v/input_ova.ml
index 5d3bece1..5829c15e 100644
--- a/v2v/input_ova.ml
+++ b/v2v/input_ova.ml
@@ -26,6 +26,7 @@ open Types
open Parse_ova
open Parse_ovf_from_ova
open Name_from_disk
+open Utils
(* RHBZ#1570407: VMware-generated OVA files found in the wild can
* contain hrefs referencing snapshots. The href will be something
@@ -132,9 +133,7 @@ class input_ova ova = object
(* The spec allows the file to be gzip-compressed, in
* which case we must uncompress it into a temporary.
*)
- let temp_dir = (open_guestfs ())#get_cachedir () in
- let new_filename = Filename.temp_file ~temp_dir "ova" ".vmdk" in
- unlink_on_exit new_filename;
+ let new_filename = Filename.temp_file ~temp_dir:cachedir "ova" ".vmdk" in
let cmd =
sprintf "zcat %s > %s" (quote filename) (quote new_filename) in
if shell_command cmd <> 0 then
diff --git a/v2v/input_vmx.ml b/v2v/input_vmx.ml
index f1d143e9..6fd60f94 100644
--- a/v2v/input_vmx.ml
+++ b/v2v/input_vmx.ml
@@ -388,11 +388,6 @@ and find_nics vmx =
nics
class input_vmx input_password input_transport arg =
- let tmpdir =
- let base_dir = (open_guestfs ())#get_cachedir () in
- let t = Mkdtemp.temp_dir ~base_dir "vmx." in
- rmdir_on_exit t;
- t in
object
inherit input
diff --git a/v2v/measure_disk.ml b/v2v/measure_disk.ml
index 5c01eaac..6a1212f0 100644
--- a/v2v/measure_disk.ml
+++ b/v2v/measure_disk.ml
@@ -21,6 +21,8 @@ open Tools_utils
open JSON_parser
open Common_gettext.Gettext
+open Utils
+
(* Run qemu-img measure on a disk. *)
let measure ?format filename =
@@ -38,8 +40,7 @@ let measure ?format filename =
List.push_back cmd "--output=json";
List.push_back cmd filename;
- let json, chan = Filename.open_temp_file "v2vmeasure" ".json" in
- unlink_on_exit json;
+ let json, chan = Filename.open_temp_file ~temp_dir:tmpdir "v2vmeasure" ".json" in
let fd = Unix.descr_of_out_channel chan in
if run_command ~stdout_fd:fd !cmd <> 0 then
error (f_"qemu-img measure failed, see earlier errors");
diff --git a/v2v/output_glance.ml b/v2v/output_glance.ml
index 0a9e9181..f2468055 100644
--- a/v2v/output_glance.ml
+++ b/v2v/output_glance.ml
@@ -27,16 +27,6 @@ open Types
open Utils
class output_glance () =
- (* Although glance can slurp in a stream from stdin, unfortunately
- * 'qemu-img convert' cannot write to a stream (although I guess
- * it could be implemented at least for raw). Therefore we have
- * to write to a temporary file. XXX
- *)
- let tmpdir =
- let base_dir = (open_guestfs ())#get_cachedir () in
- let t = Mkdtemp.temp_dir ~base_dir "glance." in
- rmdir_on_exit t;
- t in
object
inherit output
@@ -60,8 +50,12 @@ object
method supported_firmware = [ TargetBIOS; TargetUEFI ]
method prepare_targets _ overlays _ =
- (* Write targets to a temporary local file - see above for reason. *)
- List.map (fun (_, ov) -> TargetFile (tmpdir // ov.ov_sd)) overlays
+ (* Although glance can slurp in a stream from stdin, unfortunately
+ * 'qemu-img convert' cannot write to a stream (although I guess
+ * it could be implemented at least for raw). Therefore we have
+ * to write to a temporary file. XXX
+ *)
+ List.map (fun (_, ov) -> TargetFile (cachedir // ov.ov_sd)) overlays
method create_metadata source targets
target_buses guestcaps inspect target_firmware =
diff --git a/v2v/output_libvirt.ml b/v2v/output_libvirt.ml
index 033e26b1..9c189b9d 100644
--- a/v2v/output_libvirt.ml
+++ b/v2v/output_libvirt.ml
@@ -176,6 +176,9 @@ object (self)
create_libvirt_xml ~pool:pool_name source targets target_buses
guestcaps target_features target_firmware inspect in
+ (* Do not store the temporary file inside our [tmpdir], as we preserve it
+ * for the user in case Domain.define_xml fails.
+ *)
let tmpfile, chan = Filename.open_temp_file "v2vlibvirt" ".xml" in
DOM.doc_to_chan chan doc;
close_out chan;
diff --git a/v2v/output_null.ml b/v2v/output_null.ml
index 3528da50..493c9f0e 100644
--- a/v2v/output_null.ml
+++ b/v2v/output_null.ml
@@ -50,7 +50,7 @@ let can_use_qemu_null_co_device () =
(* We actually attempt to convert a raw file to the null-co device
* using a JSON URL.
*)
- let tmp = Filename.temp_file "v2vqemunullcotst" ".img" in
+ let tmp = Filename.temp_file ~temp_dir:tmpdir "v2vqemunullcotst" ".img" in
Unix.truncate tmp 1024;
let json = [
@@ -65,20 +65,10 @@ let can_use_qemu_null_co_device () =
(if verbose () then "" else " 2>&1") in
debug "%s" cmd;
let r = 0 = Sys.command cmd in
- Unix.unlink tmp;
debug "qemu-img supports the null-co device: %b" r;
r
class output_null =
- (* Create a temporary directory which is always deleted at exit,
- * so we can put the drives there in case qemu does not support
- * the null-co device w/ a JSON URL.
- *)
- let tmpdir =
- let base_dir = (open_guestfs ())#get_cachedir () in
- let t = Mkdtemp.temp_dir ~base_dir "null." in
- rmdir_on_exit t;
- t in
object
inherit output
@@ -99,7 +89,7 @@ object
List.map (fun _ -> target_file) overlays
) else (
- List.map (fun (_, ov) -> TargetFile (tmpdir // ov.ov_sd)) overlays
+ List.map (fun (_, ov) -> TargetFile (cachedir // ov.ov_sd)) overlays
)
method create_metadata _ _ _ _ _ _ = ()
diff --git a/v2v/output_openstack.ml b/v2v/output_openstack.ml
index 179b0edf..39f30c9e 100644
--- a/v2v/output_openstack.ml
+++ b/v2v/output_openstack.ml
@@ -191,8 +191,7 @@ class output_openstack output_conn output_password output_storage
let run_openstack_command_capture_json args =
let cmd = [ openstack_binary ] @ extra_args @ args in
- let json, chan = Filename.open_temp_file "v2vopenstack" ".json" in
- unlink_on_exit json;
+ let json, chan = Filename.open_temp_file ~temp_dir:tmpdir "v2vopenstack" ".json" in
let fd = descr_of_out_channel chan in
(* Note that Tools_utils.run_command closes fd.
diff --git a/v2v/output_rhv.ml b/v2v/output_rhv.ml
index 49cc0381..49bfaaa8 100644
--- a/v2v/output_rhv.ml
+++ b/v2v/output_rhv.ml
@@ -40,7 +40,7 @@ let rec mount_and_check_storage_domain domain_class os =
(* Create a mountpoint. Default mode is too restrictive for us
* when we need to write into the directory as 36:36.
*)
- let mp = Mkdtemp.temp_dir "v2v." in
+ let mp = Mkdtemp.temp_dir ~base_dir:tmpdir "v2v." in
chmod mp 0o755;
(* Try mounting it. *)
diff --git a/v2v/output_rhv_upload.ml b/v2v/output_rhv_upload.ml
index 5c6c2611..40498ba3 100644
--- a/v2v/output_rhv_upload.ml
+++ b/v2v/output_rhv_upload.ml
@@ -153,13 +153,6 @@ let json_optstring = function
class output_rhv_upload output_alloc output_conn
output_password output_storage
rhv_options =
- (* Create a temporary directory which will be deleted on exit. *)
- let tmpdir =
- let base_dir = (open_guestfs ())#get_cachedir () in
- let t = Mkdtemp.temp_dir ~base_dir "rhvupload." in
- rmdir_on_exit t;
- t in
-
let diskid_file_of_id id = tmpdir // sprintf "diskid.%d" id in
(* Create Python scripts for precheck, vmcheck, plugin and create VM. *)
diff --git a/v2v/parse_ova.ml b/v2v/parse_ova.ml
index 0b939ac4..5c8d349f 100644
--- a/v2v/parse_ova.ml
+++ b/v2v/parse_ova.ml
@@ -70,11 +70,10 @@ let rec parse_ova ova =
let top_dir, ova_type =
if is_directory ova then ova, Directory
else (
- let tmpdir =
- let base_dir = (open_guestfs ())#get_cachedir () in
- let t = Mkdtemp.temp_dir ~base_dir "ova." in
- rmdir_on_exit t;
- t in
+ let ovatmpdir =
+ let d = cachedir // "ova" in
+ Unix.mkdir d 0o700;
+ d in
match detect_file_type ova with
| `Tar ->
@@ -85,15 +84,15 @@ let rec parse_ova ova =
*)
if qemu_img_supports_offset_and_size () &&
libvirt_supports_json_raw_driver () &&
- (untar_metadata ova tmpdir;
- no_disks_are_compressed ova tmpdir) then
- tmpdir, TarOptimized ova
+ (untar_metadata ova ovatmpdir;
+ no_disks_are_compressed ova ovatmpdir) then
+ ovatmpdir, TarOptimized ova
else (
(* If qemu/libvirt is too old or any disk is compressed
* then we must fall back on the slow path.
*)
- untar ova tmpdir;
- tmpdir, Directory
+ untar ova ovatmpdir;
+ ovatmpdir, Directory
)
| `Zip ->
@@ -102,16 +101,16 @@ let rec parse_ova ova =
*)
let cmd =
[ "unzip" ] @ (if verbose () then [] else [ "-q" ]) @
- [ "-j"; "-d"; tmpdir; ova ] in
+ [ "-j"; "-d"; ovatmpdir; ova ] in
if run_command cmd <> 0 then
error (f_"error unpacking %s, see earlier error messages") ova;
- tmpdir, Directory
+ ovatmpdir, Directory
| (`GZip|`XZ) as format ->
(match uncompressed_type format ova with
| `Tar ->
- untar ~format ova tmpdir;
- tmpdir, Directory
+ untar ~format ova ovatmpdir;
+ ovatmpdir, Directory
| `Zip | `GZip | `XZ | `Unknown ->
error (f_"%s: unsupported file format\n\nFormats which we currently understand for '-i ova' are: tar (uncompressed, compress with gzip or xz), zip") ova
)
@@ -222,11 +221,10 @@ and uncompress_head format file =
and uncompressed_type format file =
let head, headlen = uncompress_head format file in
let tmpfile, chan =
- Filename.open_temp_file "ova.file." "" in
+ Filename.open_temp_file ~temp_dir:tmpdir "ova.file." "" in
output chan head 0 headlen;
close_out chan;
let ret = detect_file_type tmpfile in
- Sys.remove tmpfile;
ret
(* Find files in [dir] ending with [ext]. *)
diff --git a/v2v/utils.ml b/v2v/utils.ml
index ccbb9d68..3dbb4da9 100644
--- a/v2v/utils.ml
+++ b/v2v/utils.ml
@@ -22,8 +22,30 @@ open Printf
open Std_utils
open Tools_utils
+open Unix_utils
open Common_gettext.Gettext
+let lazy_tmpdir =
+ lazy (
+ let tmpdir = Mkdtemp.temp_dir "virt-v2v." in
+ rmdir_on_exit tmpdir;
+ tmpdir
+ )
+
+let lazy_cachedir =
+ lazy (
+ let base_dir = (open_guestfs ())#get_cachedir () in
+ let cachedir = Mkdtemp.temp_dir ~base_dir "virt-v2v." in
+ rmdir_on_exit cachedir;
+ cachedir
+ )
+
+let tmpdir =
+ Lazy.force lazy_tmpdir
+
+let cachedir =
+ Lazy.force lazy_cachedir
+
(* Is SELinux enabled and enforcing on the host? *)
let have_selinux =
0 = Sys.command "getenforce 2>/dev/null | grep -isq Enforcing"
@@ -112,7 +134,7 @@ let qemu_img_supports_offset_and_size () =
(* We actually attempt to create a qcow2 file with a raw backing
* file that has an offset and size.
*)
- let tmp = Filename.temp_file "v2vqemuimgtst" ".img" in
+ let tmp = Filename.temp_file ~temp_dir:tmpdir "v2vqemuimgtst" ".img" in
Unix.truncate tmp 1024;
let json = [
@@ -132,7 +154,6 @@ let qemu_img_supports_offset_and_size () =
(if verbose () then "" else " 2>&1") in
debug "%s" cmd;
let r = 0 = Sys.command cmd in
- Unix.unlink tmp;
debug "qemu-img supports \"offset\" and \"size\" in json URLs: %b" r;
r
diff --git a/v2v/utils.mli b/v2v/utils.mli
index 937e2b9b..8f279263 100644
--- a/v2v/utils.mli
+++ b/v2v/utils.mli
@@ -18,6 +18,13 @@
(** Utilities used in virt-v2v only. *)
+val tmpdir : string
+(** The single temporary directory of virt-v2v for small files. *)
+
+val cachedir : string
+(** The single temporary directory of virt-v2v for big files,
+ such as disks. *)
+
val have_selinux : bool
(** True if SELinux is enabled and enforcing on the host. *)
diff --git a/v2v/v2v.ml b/v2v/v2v.ml
index 73edff2c..6e88d978 100644
--- a/v2v/v2v.ml
+++ b/v2v/v2v.ml
@@ -264,8 +264,6 @@ and set_source_networks_and_bridges cmdline source =
let nics = List.map (Networks.map cmdline.network_map) source.s_nics in
{ source with s_nics = nics }
-and overlay_dir = (open_guestfs ())#get_cachedir ()
-
(* Conversion can fail or hang if there is insufficient free space in
* the temporary directory used to store overlays on the host
* (RHBZ#1316479). Although only a few hundred MB is actually
@@ -273,12 +271,12 @@ and overlay_dir = (open_guestfs ())#get_cachedir ()
* guestfs appliance which is also stored here.
*)
and check_host_free_space () =
- let free_space = StatVFS.free_space (StatVFS.statvfs overlay_dir) in
- debug "check_host_free_space: overlay_dir=%s free_space=%Ld"
- overlay_dir free_space;
+ let free_space = StatVFS.free_space (StatVFS.statvfs cachedir) in
+ debug "check_host_free_space: cachedir=%s free_space=%Ld"
+ cachedir free_space;
if free_space < 1_073_741_824L then
error (f_"insufficient free space in the conversion server temporary directory %s (%s).\n\nEither free up space in that directory, or set the LIBGUESTFS_CACHEDIR environment variable to point to another directory with more than 1GB of free space.\n\nSee also the virt-v2v(1) manual, section \"Minimum free space check in the host\".")
- overlay_dir (human_size free_space)
+ cachedir (human_size free_space)
(* Create a qcow2 v3 overlay to protect the source image(s). *)
and create_overlays source_disks =
@@ -286,8 +284,7 @@ and create_overlays source_disks =
List.mapi (
fun i ({ s_qemu_uri = qemu_uri; s_format = format } as source) ->
let overlay_file =
- Filename.temp_file ~temp_dir:overlay_dir "v2vovl" ".qcow2" in
- unlink_on_exit overlay_file;
+ Filename.temp_file ~temp_dir:cachedir "v2vovl" ".qcow2" in
(* There is a specific reason to use the newer qcow2 variant:
* Because the L2 table can store zero clusters efficiently, and
@@ -823,7 +820,7 @@ and preserve_overlays overlays src_name =
List.iter (
fun ov ->
let saved_filename =
- sprintf "%s/%s-%s.qcow2" overlay_dir src_name ov.ov_sd in
+ sprintf "%s/%s-%s.qcow2" cachedir src_name ov.ov_sd in
rename ov.ov_overlay_file saved_filename;
info (f_"Overlay saved as %s [--debug-overlays]") saved_filename
) overlays
--
2.25.1
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