[Qemu-devel] [PATCH] qapi: add 'query-target' command to return target arch/bit size

[Daniel P. Berrange]

From: "Daniel P. Berrange" <address@hidden>

Add a 'query-target' QAPI command to allow management applications
to determine what target architecture a QEMU binary is emulating
without having to parse the binary name or -help output

  $ qmp-shell -p /tmp/qemu
  (QEMU) query-target
  {   u'return': {   u'arch': u'x86_64', u'bits': 64}}

Signed-off-by: Daniel P. Berrange <address@hidden>
---
 arch_init.c      | 11 +++++++++++
 qapi-schema.json | 25 +++++++++++++++++++++++++
 qmp-commands.hx  |  5 +++++
 3 files changed, 41 insertions(+)

diff --git a/arch_init.c b/arch_init.c
index 9b46bfc..095672d 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -1080,3 +1080,14 @@ int xen_available(void)
     return 0;
 #endif
 }
+
+
+TargetInfo *qmp_query_target(Error **errp)
+{
+    TargetInfo *info = g_malloc0(sizeof(*info));
+
+    info->arch = g_strdup(TARGET_ARCH);
+    info->bits = TARGET_PHYS_ADDR_BITS;
+
+    return info;
+}
diff --git a/qapi-schema.json b/qapi-schema.json
index 3d2b2d1..f0e3fe0 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -2454,3 +2454,28 @@
 #
 ##
 { 'command': 'query-fdsets', 'returns': ['FdsetInfo'] }
+
+##
+# @TargetInfo:
+#
+# Information describing the QEMU target.
+#
+# @arch: the name of the target architecture (eg "x86_64", "i686", etc)
+#
+# @bits: number of bits in physical address (eg 32 or 64)
+#
+# Since: 1.2.0
+##
+{ 'type': 'TargetInfo',
+  'data': { 'arch': 'str', 'bits': 'int' } }
+
+##
+# @query-target:
+#
+# Return information about the target for this QEMU
+#
+# Returns: TargetInfo
+#
+# Since: 1.2.0
+##
+{ 'command': 'query-target', 'returns': 'TargetInfo' }
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 2ce4ce6..00d798f 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -2509,3 +2509,8 @@ EQMP
         .mhandler.cmd_new = qmp_marshal_input_query_cpu_definitions,
     },
 
+    {
+        .name       = "query-target",
+        .args_type  = "",
+        .mhandler.cmd_new = qmp_marshal_input_query_target,
+    },
-- 
1.7.11.2