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| author | Richard Jones <rjones@redhat.com> | 2010-06-16 15:25:45 +0100 |
|---|---|---|
| committer | Richard Jones <rjones@redhat.com> | 2010-06-16 15:32:20 +0100 |
| commit | 1079f74704a06c06996e547fdecf20a8f92799c6 (patch) | |
| tree | 32b272a9b86952f06f8565526c1fe5d8cf09bee7 /ocaml/t | |
| parent | 1e568f057e8bb7b36cc14e0e531d74b75ad9cb6c (diff) | |
| download | libguestfs-1079f74704a06c06996e547fdecf20a8f92799c6.tar.gz libguestfs-1079f74704a06c06996e547fdecf20a8f92799c6.tar.xz libguestfs-1079f74704a06c06996e547fdecf20a8f92799c6.zip | |
ocaml: Fix thread safety of strings in bindings (RHBZ#604691).
There's a thread safety issue with the current OCaml bindings which
is well explained in the bug report:
https://bugzilla.redhat.com/show_bug.cgi?id=604691
This commit fixes the safety issue by copying strings temporarily
before releasing the thread lock. Updated code looks like this:
char *filename = guestfs_safe_strdup (g, String_val (filenamev));
int r;
caml_enter_blocking_section ();
r = guestfs_add_drive_ro (g, filename);
caml_leave_blocking_section ();
free (filename);
if (r == -1)
ocaml_guestfs_raise_error (g, "add_drive_ro");
Also included is a regression test.
Diffstat (limited to 'ocaml/t')
| -rw-r--r-- | ocaml/t/guestfs_070_threads.ml | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/ocaml/t/guestfs_070_threads.ml b/ocaml/t/guestfs_070_threads.ml new file mode 100644 index 00000000..e13ac7b6 --- /dev/null +++ b/ocaml/t/guestfs_070_threads.ml @@ -0,0 +1,72 @@ +(* libguestfs OCaml bindings + * Copyright (C) 2010 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., 675 Mass Ave, Cambridge, MA 02139, USA. + *) + +open Unix + +(* Start a background thread which does lots of allocation and + * GC activity. + *) +let thread = Thread.create ( + fun () -> + while true do + Gc.compact (); + ignore (Array.init 1000 (fun i -> Thread.yield (); String.create (8*i))) + done +) () + +let () = + let g = Guestfs.create () in + + let fd = openfile "test.img" [O_WRONLY;O_CREAT;O_NOCTTY;O_TRUNC] 0o666 in + ftruncate fd (500 * 1024 * 1024); + close fd; + + (* Copy these strings so they're located on the heap and + * subject to garbage collection. + *) + let s = String.copy "test.img" in + Guestfs.add_drive_ro g s; + Guestfs.launch g; + + let dev = String.copy "/dev/sda" in + Guestfs.pvcreate g dev; + let vg = String.copy "VG" in + Guestfs.vgcreate g vg [|dev|]; + let s = String.copy "LV1" in + Guestfs.lvcreate g s vg 200; + let s = String.copy "LV2" in + Guestfs.lvcreate g s vg 200; + + let lvs = Guestfs.lvs g in + if lvs <> [|"/dev/VG/LV1"; "/dev/VG/LV2"|] then + failwith "Guestfs.lvs returned incorrect result"; + + let s = String.copy "ext3" in + let lv = String.copy "/dev/VG/LV1" in + Guestfs.mkfs g s lv; + let s = String.copy "/" in + Guestfs.mount_options g "" lv s; + let s = String.copy "/test" in + Guestfs.touch g s; + + Guestfs.umount_all g; + Guestfs.sync g; + Guestfs.close g; + unlink "test.img"; + Gc.compact (); + exit 0 |