From 2404f718a08c82ecc697f64b7d539f2a44d210ee Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Tue, 8 Jan 2019 13:40:44 +0000
Subject: [PATCH] Small fix for qemu behaviour (RHBZ#1664318).

---
 ...-info-U-option-to-avoid-locking-erro.patch | 103 ++++++++++++++++++
 libguestfs.spec                               |   6 +
 2 files changed, 109 insertions(+)
 create mode 100644 0001-lib-Use-qemu-img-info-U-option-to-avoid-locking-erro.patch

diff --git a/0001-lib-Use-qemu-img-info-U-option-to-avoid-locking-erro.patch b/0001-lib-Use-qemu-img-info-U-option-to-avoid-locking-erro.patch
new file mode 100644
index 0000000..8628850
--- /dev/null
+++ b/0001-lib-Use-qemu-img-info-U-option-to-avoid-locking-erro.patch
@@ -0,0 +1,103 @@
+From f00f920ad3b15ab8e9e8f201c16e7628b6b7b109 Mon Sep 17 00:00:00 2001
+From: "Richard W.M. Jones" <rjones@redhat.com>
+Date: Wed, 12 Sep 2018 17:16:20 +0100
+Subject: [PATCH] lib: Use qemu-img info -U option to avoid locking error.
+
+https://bugs.launchpad.net/qemu/+bug/1740364
+---
+ lib/guestfs-internal.h |  3 +++
+ lib/handle.c           |  2 ++
+ lib/info.c             | 39 +++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 44 insertions(+)
+
+diff --git a/lib/guestfs-internal.h b/lib/guestfs-internal.h
+index 471244264..6c339ae81 100644
+--- a/lib/guestfs-internal.h
++++ b/lib/guestfs-internal.h
+@@ -510,6 +510,9 @@ struct guestfs_h {
+   /* Cached features. */
+   struct cached_feature *features;
+   size_t nr_features;
++
++  /* Used by lib/info.c.  -1 = not tested or error; else 0 or 1. */
++  int qemu_img_supports_U_option;
+ };
+ 
+ /**
+diff --git a/lib/handle.c b/lib/handle.c
+index a47aaafab..297ff6d67 100644
+--- a/lib/handle.c
++++ b/lib/handle.c
+@@ -101,6 +101,8 @@ guestfs_create_flags (unsigned flags, ...)
+ 
+   g->memsize = DEFAULT_MEMSIZE;
+ 
++  g->qemu_img_supports_U_option = -1; /* not tested, see lib/info.c */
++
+   /* Start with large serial numbers so they are easy to spot
+    * inside the protocol.
+    */
+diff --git a/lib/info.c b/lib/info.c
+index 2eadc1c11..4dee7a26a 100644
+--- a/lib/info.c
++++ b/lib/info.c
+@@ -57,6 +57,7 @@ cleanup_json_t_decref (void *ptr)
+ #endif
+ 
+ static json_t *get_json_output (guestfs_h *g, const char *filename);
++static int qemu_img_supports_U_option (guestfs_h *g);
+ static void set_child_rlimits (struct command *);
+ 
+ char *
+@@ -149,6 +150,11 @@ get_json_output (guestfs_h *g, const char *filename)
+ 
+   guestfs_int_cmd_add_arg (cmd, "qemu-img");
+   guestfs_int_cmd_add_arg (cmd, "info");
++  switch (qemu_img_supports_U_option (g)) {
++  case -1: return NULL;
++  case 0:  break;
++  default: guestfs_int_cmd_add_arg (cmd, "-U");
++  }
+   guestfs_int_cmd_add_arg (cmd, "--output");
+   guestfs_int_cmd_add_arg (cmd, "json");
+   if (filename[0] == '/')
+@@ -218,3 +224,36 @@ set_child_rlimits (struct command *cmd)
+   guestfs_int_cmd_set_child_rlimit (cmd, RLIMIT_CPU, 10 /* seconds */);
+ #endif
+ }
++
++/**
++ * Test if the qemu-img info command supports the C<-U> option to
++ * disable locking.  The result is memoized in the handle.
++ *
++ * Note this option was added in qemu 2.11.  We can remove this test
++ * when we can assume everyone is using qemu >= 2.11.
++ */
++static int
++qemu_img_supports_U_option (guestfs_h *g)
++{
++  if (g->qemu_img_supports_U_option >= 0)
++    return g->qemu_img_supports_U_option;
++
++  CLEANUP_CMD_CLOSE struct command *cmd = guestfs_int_new_command (g);
++  int r;
++
++  guestfs_int_cmd_add_string_unquoted (cmd,
++                                       "qemu-img --help | "
++                                       "grep -sqE -- '\\binfo\\b.*-U\\b'");
++  r = guestfs_int_cmd_run (cmd);
++  if (r == -1)
++    return -1;
++  if (!WIFEXITED (r)) {
++    guestfs_int_external_command_failed (g, r,
++                                         "qemu-img info -U option test",
++                                         NULL);
++    return -1;
++  }
++
++  g->qemu_img_supports_U_option = WEXITSTATUS (r) == 0;
++  return g->qemu_img_supports_U_option;
++}
+-- 
+2.19.2
+
diff --git a/libguestfs.spec b/libguestfs.spec
index c9dc9e9..f60c112 100644
--- a/libguestfs.spec
+++ b/libguestfs.spec
@@ -50,6 +50,9 @@ Source0:       http://libguestfs.org/download/1.38-stable/%{name}-%{version}.tar
 Source1:       http://libguestfs.org/download/1.38-stable/%{name}-%{version}.tar.gz.sig
 %endif
 
+# https://bugzilla.redhat.com/show_bug.cgi?id=1664318
+Patch1:        0001-lib-Use-qemu-img-info-U-option-to-avoid-locking-erro.patch
+
 # Replacement README file for Fedora users.
 Source4:       README-replacement.in
 
@@ -1404,6 +1407,9 @@ install -m 0644 utils/boot-benchmark/boot-benchmark.1 $RPM_BUILD_ROOT%{_mandir}/
 
 
 %changelog
+* Tue Jan 08 2019 Richard W.M. Jones <rjones@redhat.com> - 1:1.39.11-3
+- Small fix for qemu behaviour (RHBZ#1664318).
+
 * Fri Oct 12 2018 Richard W.M. Jones <rjones@redhat.com> - 1:1.39.11-2
 - lib: Add Recommends for libvirt-daemon-config-network so that networking
   works out of the box.