[libvirt] [PATCH for 1.2.7 3/8] virsh: expose virConnectGetDomainCapabilities

[Michal Privoznik]

The API is exposed under 'domcapabilities' command. Currently, with
the variety of drivers that libvirt supports, none of the command
arguments is obligatory, but all are optional instead.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 tools/virsh-host.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 tools/virsh.pod    | 16 +++++++++++
 2 files changed, 100 insertions(+)

diff --git a/tools/virsh-host.c b/tools/virsh-host.c
index 734f1a8..a1d8465 100644
--- a/tools/virsh-host.c
+++ b/tools/virsh-host.c
@@ -69,6 +69,84 @@ cmdCapabilities(vshControl *ctl, const vshCmd *cmd ATTRIBUTE_UNUSED)
 }
 
 /*
+ * "domcapabilities" command
+ */
+static const vshCmdInfo info_domcapabilities[] = {
+    {.name = "help",
+     .data = N_("domain capabilities")
+    },
+    {.name = "desc",
+     .data = N_("Returns capabilities of emulator with respect to host and libvirt.")
+    },
+    {.name = NULL}
+};
+
+static const vshCmdOptDef opts_domcapabilities[] = {
+    {.name = "virttype",
+     .type = VSH_OT_STRING,
+     .help = N_("virtualization type (/domain/@type)"),
+    },
+    {.name = "emulatorbin",
+     .type = VSH_OT_STRING,
+     .help = N_("path to emulator binary (/domain/devices/emulator)"),
+    },
+    {.name = "arch",
+     .type = VSH_OT_STRING,
+     .help = N_("domain architecture (/domain/os/type/@arch)"),
+    },
+    {.name = "machine",
+     .type = VSH_OT_STRING,
+     .help = N_("machine type (/domain/os/type/@machine)"),
+    },
+    {.name = NULL}
+};
+
+static bool
+cmdDomCapabilities(vshControl *ctl, const vshCmd *cmd)
+{
+    bool ret = false;
+    char *caps;
+    const char *virttype = NULL;
+    const char *emulatorbin = NULL;
+    const char *arch = NULL;
+    const char *machine = NULL;
+    const unsigned int flags = 0; /* No flags so far */
+
+    if (vshCommandOptString(cmd, "virttype", &virttype) < 0) {
+        vshError(ctl, "%s", _("ble"));
+        goto cleanup;
+    }
+
+    if (vshCommandOptString(cmd, "emulatorbin", &emulatorbin) < 0) {
+        vshError(ctl, "%s", _("ble"));
+        goto cleanup;
+    }
+
+    if (vshCommandOptString(cmd, "arch", &arch) < 0) {
+        vshError(ctl, "%s", _("ble"));
+        goto cleanup;
+    }
+
+    if (vshCommandOptString(cmd, "machine", &machine) < 0) {
+        vshError(ctl, "%s", _("ble"));
+        goto cleanup;
+    }
+
+    caps = virConnectGetDomainCapabilities(ctl->conn, emulatorbin,
+                                           arch, machine, virttype, flags);
+    if (!caps) {
+        vshError(ctl, "%s", _("failed to get emulator capabilities"));
+        goto cleanup;
+    }
+
+    vshPrint(ctl, "%s\n", caps);
+    ret = true;
+ cleanup:
+    VIR_FREE(caps);
+    return ret;
+}
+
+/*
  * "freecell" command
  */
 static const vshCmdInfo info_freecell[] = {
@@ -1131,6 +1209,12 @@ const vshCmdDef hostAndHypervisorCmds[] = {
      .info = info_cpu_models,
      .flags = 0
     },
+    {.name = "domcapabilities",
+     .handler = cmdDomCapabilities,
+     .opts = opts_domcapabilities,
+     .info = info_domcapabilities,
+     .flags = 0
+    },
     {.name = "freecell",
      .handler = cmdFreecell,
      .opts = opts_freecell,
diff --git a/tools/virsh.pod b/tools/virsh.pod
index b248c9a..b37a2be 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -350,6 +350,22 @@ description see:
   L<http://libvirt.org/formatcaps.html>
 The XML also show the NUMA topology information if available.
 
+=item B<domcapabilities> [I<virttype>] [I<emulatorbin>]
+[I<arch>] [I<machine>]
+
+Print an XML document describing the capabilities of the
+hypervisor we are currently connected to. This may be useful if
+you intend to create a new domain and are curious if for instance
+should use VFIO or legacy KVM device passthrough. The I<virttype>
+specifies the virtualization used (the domain XML counterpart is
+the 'type' attribute of the <domain/> top level element). Then,
+the I<emulatorbin> specifies the path to the emulator (this is
+same as <emulator> element in the domain XML). Then, the I<arch>
+argument sets the domain architecture (exposed under
+/domain/os/type/@arch attribute). Then at last I<machine>
+overrides the default machine for the emulator (can be found in
+domain XML under /domain/os/type).
+
 =item B<inject-nmi> I<domain>
 
 Inject NMI to the guest.
-- 
1.8.5.5