[Qemu-devel] [PATCH v2 0/7] qom: misc fixes & enhancements to support TLS work

[Qemu-devel] [PATCH v2 0/7] qom: misc fixes & enhancements to support TLS work

[Daniel P. Berrange]

This series contains the 7 generic QOM API fixes and enhancements
that I previously posted as part of the large series refactoring
and extending the TLS support in QEMU:

  https://lists.gnu.org/archive/html/qemu-devel/2015-04/msg02038.html

I'm sending it separately, since the patches are reasonably well
self-contained and thus hopefully suitable for quicker review and
merge.

Changed in v2:

 - Pass "Object * parent" instead of "char *path" paremeter
 - Rely on stable reference from parent to keep new object alive
 - Use object_unparent() where appropriate

Daniel P. Berrange (7):
  qom: fix typename of 'policy' enum property in hostmem obj
  qom: document user creatable object types in help text
  qom: create objects in two phases
  qom: add object_new_propv / object_new_proplist constructors
  qom: make enum string tables const-correct
  qom: add a object_property_add_enum helper method
  qom: don't pass string table to object_get_enum method

 backends/hostmem.c          |  22 ++--
 include/hw/qdev-core.h      |   2 +-
 include/qapi/util.h         |   2 +-
 include/qapi/visitor-impl.h |   6 +-
 include/qapi/visitor.h      |   2 +-
 include/qom/object.h        |  87 ++++++++++++-
 numa.c                      |   2 +-
 qapi/qapi-dealloc-visitor.c |   3 +-
 qapi/qapi-util.c            |   2 +-
 qapi/qapi-visit-core.c      |   6 +-
 qemu-options.hx             |  70 +++++++---
 qom/object.c                | 145 ++++++++++++++++++++-
 scripts/qapi-types.py       |   4 +-
 tests/.gitignore            |   1 +
 tests/Makefile              |   5 +-
 tests/check-qom-proplist.c  | 308 ++++++++++++++++++++++++++++++++++++++++++++
 vl.c                        |  40 +++++-
 17 files changed, 657 insertions(+), 50 deletions(-)
 create mode 100644 tests/check-qom-proplist.c

-- 
2.1.0

[Qemu-devel] [PATCH v2 1/7] qom: fix typename of 'policy' enum property in hostmem obj

[Daniel P. Berrange]

The 'policy' property was being registered with a typename of
'str', but it is in fact an enum of the 'HostMemPolicy' type.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 backends/hostmem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/backends/hostmem.c b/backends/hostmem.c
index b7b6cf8..f6db33c 100644
--- a/backends/hostmem.c
+++ b/backends/hostmem.c
@@ -252,7 +252,7 @@ static void host_memory_backend_init(Object *obj)
     object_property_add(obj, "host-nodes", "int",
                         host_memory_backend_get_host_nodes,
                         host_memory_backend_set_host_nodes, NULL, NULL, NULL);
-    object_property_add(obj, "policy", "str",
+    object_property_add(obj, "policy", "HostMemPolicy",
                         host_memory_backend_get_policy,
                         host_memory_backend_set_policy, NULL, NULL, NULL);
 }
-- 
2.1.0

[Qemu-devel] [PATCH v2 2/7] qom: document user creatable object types in help text

[Daniel P. Berrange]

The QEMU help for -object is essentially useless, just giving users
the generic syntax. Move it down into its own section and introduce
a nested table where each user creatable object can be documented.
The existing memory-backend-file, rng-random and rng-egd object
types are documented.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 qemu-options.hx | 70 ++++++++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 54 insertions(+), 16 deletions(-)

diff --git a/qemu-options.hx b/qemu-options.hx
index 319d971..5ef0ae4 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -3421,22 +3421,6 @@ DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
 HXCOMM Deprecated (ignored)
 DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
 
-DEF("object", HAS_ARG, QEMU_OPTION_object,
-    "-object TYPENAME[,PROP1=VALUE1,...]\n"
-    "                create an new object of type TYPENAME setting properties\n"
-    "                in the order they are specified.  Note that the 'id'\n"
-    "                property must be set.  These objects are placed in the\n"
-    "                '/objects' path.\n",
-    QEMU_ARCH_ALL)
-STEXI
-@item -object @var{typename}[,@var{prop1}=@var{value1},...]
-@findex -object
-Create an new object of type @var{typename} setting properties
-in the order they are specified.  Note that the 'id'
-property must be set.  These objects are placed in the
-'/objects' path.
-ETEXI
-
 DEF("msg", HAS_ARG, QEMU_OPTION_msg,
     "-msg timestamp[=on|off]\n"
     "                change the format of messages\n"
@@ -3462,6 +3446,60 @@ Dump json-encoded vmstate information for current machine type to file
 in @var{file}
 ETEXI
 
+DEFHEADING(Generic object creation)
+
+DEF("object", HAS_ARG, QEMU_OPTION_object,
+    "-object TYPENAME[,PROP1=VALUE1,...]\n"
+    "                create an new object of type TYPENAME setting properties\n"
+    "                in the order they are specified.  Note that the 'id'\n"
+    "                property must be set.  These objects are placed in the\n"
+    "                '/objects' path.\n",
+    QEMU_ARCH_ALL)
+STEXI
+@item -object @var{typename}[,@var{prop1}=@var{value1},...]
+@findex -object
+Create an new object of type @var{typename} setting properties
+in the order they are specified.  Note that the 'id'
+property must be set.  These objects are placed in the
+'/objects' path.
+
+@table @option
+
+@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off}
+
+Creates a memory file backend object, which can be used to back
+the guest RAM with huge pages. The @option{id} parameter is a
+unique ID that will be used to reference this memory region
+when configuring the @option{-numa} argument. The @option{size}
+option provides the size of the memory region, and accepts
+common suffixes, eg @option{500M}. The @option{mem-path} provides
+the path to either a shared memory or huge page filesystem mount.
+The @option{share} boolean option determines whether the memory
+region is marked as private to QEMU, or shared. The latter allows
+a co-operating external process to access the QEMU memory region.
+
+@item -object rng-random,id=@var{id},filename=@var{/dev/random}
+
+Creates a random number generator backend which obtains entropy from
+a device on the host. The @option{id} parameter is a unique ID that
+will be used to reference this entropy backend from the @option{virtio-rng}
+device. The @option{filename} parameter specifies which file to obtain
+entropy from and if omitted defaults to @option{/dev/random}.
+
+@item -object rng-egd,id=@var{id},chardev=@var{chardevid}
+
+Creates a random number generator backend which obtains entropy from
+an external daemon running on the host. The @option{id} parameter is
+a unique ID that will be used to reference this entropy backend from
+the @option{virtio-rng} device. The @option{chardev} parameter is
+the unique ID of a character device backend that provides the connection
+to the RNG daemon.
+
+@end table
+
+ETEXI
+
+
 HXCOMM This is the last statement. Insert new options before this line!
 STEXI
 @end table
-- 
2.1.0

[Qemu-devel] [PATCH v2 3/7] qom: create objects in two phases

[Daniel P. Berrange]

Some types of object must be created before chardevs, other types of
object must be created after chardevs. As such there is no option but
to create objects in two phases.

This takes the decision to create as many object types as possible
in the first phase, and only delay those which have a dependency on
the chardevs. Hopefully the set which need delaying will remain
small.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 vl.c | 40 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 39 insertions(+), 1 deletion(-)

diff --git a/vl.c b/vl.c
index 74c2681..ee2f70a 100644
--- a/vl.c
+++ b/vl.c
@@ -2591,6 +2591,33 @@ static int machine_set_property(const char *name, const char *value,
     return 0;
 }
 
+
+/**
+ * Initial object creation happens before all other
+ * QEMU data types are created. The majority of objects
+ * can be created at this point. The rng-egd object
+ * cannot be created here, as it depends on the chardev
+ * already existing.
+ */
+static bool object_create_initial(const char *type)
+{
+    if (g_str_equal(type, "rng-egd")) {
+        return false;
+    }
+    return true;
+}
+
+
+/**
+ * The remainder of object creation happens after the
+ * creation of chardev, fsdev and device data types.
+ */
+static bool object_create_delayed(const char *type)
+{
+    return !object_create_initial(type);
+}
+
+
 static int object_create(QemuOpts *opts, void *opaque)
 {
     Error *err = NULL;
@@ -2599,6 +2626,7 @@ static int object_create(QemuOpts *opts, void *opaque)
     void *dummy = NULL;
     OptsVisitor *ov;
     QDict *pdict;
+    bool (*type_predicate)(const char *) = opaque;
 
     ov = opts_visitor_new(opts);
     pdict = qemu_opts_to_qdict(opts, NULL);
@@ -2613,6 +2641,9 @@ static int object_create(QemuOpts *opts, void *opaque)
     if (err) {
         goto out;
     }
+    if (!type_predicate(type)) {
+        goto out;
+    }
 
     qdict_del(pdict, "id");
     visit_type_str(opts_get_visitor(ov), &id, "id", &err);
@@ -4008,6 +4039,12 @@ int main(int argc, char **argv, char **envp)
 
     socket_init();
 
+    if (qemu_opts_foreach(qemu_find_opts("object"),
+                          object_create,
+                          object_create_initial, 0) != 0) {
+        exit(1);
+    }
+
     if (qemu_opts_foreach(qemu_find_opts("chardev"), chardev_init_func, NULL, 1) != 0)
         exit(1);
 #ifdef CONFIG_VIRTFS
@@ -4027,7 +4064,8 @@ int main(int argc, char **argv, char **envp)
     }
 
     if (qemu_opts_foreach(qemu_find_opts("object"),
-                          object_create, NULL, 0) != 0) {
+                          object_create,
+                          object_create_delayed, 0) != 0) {
         exit(1);
     }
 
-- 
2.1.0

[Qemu-devel] [PATCH v2 4/7] qom: add object_new_propv / object_new_proplist constructors

[Daniel P. Berrange]

It is reasonably common to want to create an object, set a
number of properties, register it in the hierarchy and then
mark it as complete (if a user creatable type). This requires
quite a lot of error prone, verbose, boilerplate code to achieve.

The object_new_propv / object_new_proplist constructors will
simplify this task by performing all required steps in one go,
accepting the property names/values as variadic args.

Usage would be:

   Error *err = NULL;
   Object *obj;
   obj = object_new_propv(TYPE_MEMORY_BACKEND_FILE,
                          "/objects",
                          "hostmem0",
                          &err,
                          "share", "yes",
                          "mem-path", "/dev/shm/somefile",
                          "prealloc", "yes",
                          "size", "1048576",
                          NULL);

Note all property values are passed in string form and will
be parsed into their required data types.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 include/qom/object.h       |  64 +++++++++++++++
 qom/object.c               |  67 ++++++++++++++++
 tests/.gitignore           |   1 +
 tests/Makefile             |   5 +-
 tests/check-qom-proplist.c | 190 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 326 insertions(+), 1 deletion(-)
 create mode 100644 tests/check-qom-proplist.c

diff --git a/include/qom/object.h b/include/qom/object.h
index d2d7748..6365b91 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -607,6 +607,70 @@ Object *object_new(const char *typename);
 Object *object_new_with_type(Type type);
 
 /**
+ * object_new_propv:
+ * @typename:  The name of the type of the object to instantiate.
+ * @path: the object path to register under
+ * @id: The unique ID of the object
+ * @errp: pointer to error object
+ * @...: list of property names and values
+ *
+ * This function with initialize a new object using heap allocated memory.
+ * The returned object has a reference count of 1, and will be freed when
+ * the last reference is dropped.
+ *
+ * The @id parameter will be used to register the object in the /objects
+ * hierarchy.
+ *
+ * The variadic parameters are a list of pairs of (propname, propvalue)
+ * strings. The propname of NULL indicates the end of the property
+ * list. If the object implements the user creatable interface, the
+ * object will be marked complete once all the properties have been
+ * processed.
+ *
+ *   Error *err = NULL;
+ *   Object *obj;
+ *
+ *   obj = object_new_propv(TYPE_MEMORY_BACKEND_FILE,
+ *                          "/objects",
+ *                          "hostmem0",
+ *                          &err,
+ *                          "share", "yes",
+ *                          "mem-path", "/dev/shm/somefile",
+ *                          "prealloc", "yes",
+ *                          "size", "1048576",
+ *                          NULL);
+ *
+ *   if (!obj) {
+ *     g_printerr("Cannot create memory backend: %s\n",
+ *                error_get_pretty(err));
+ *   }
+ *
+ * Returns: The newly allocated, instantiated & initialized object.
+ */
+Object *object_new_propv(const char *typename,
+                         const char *path,
+                         const char *id,
+                         Error **errp,
+                         ...)
+    __attribute__((sentinel));
+
+/**
+ * object_new_proplist:
+ * @typename:  The name of the type of the object to instantiate.
+ * @path: the object path to register under
+ * @id: The unique ID of the object
+ * @errp: pointer to error object
+ * @vargs: list of property names and values
+ *
+ * See object_new_propv for documentation.
+ */
+Object *object_new_proplist(const char *typename,
+                            const char *path,
+                            const char *id,
+                            Error **errp,
+                            va_list vargs);
+
+/**
  * object_initialize_with_type:
  * @data: A pointer to the memory to be used for the object.
  * @size: The maximum size available at @data for the object.
diff --git a/qom/object.c b/qom/object.c
index b8dff43..8927261 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -11,6 +11,7 @@
  */
 
 #include "qom/object.h"
+#include "qom/object_interfaces.h"
 #include "qemu-common.h"
 #include "qapi/visitor.h"
 #include "qapi-visit.h"
@@ -439,6 +440,72 @@ Object *object_new(const char *typename)
     return object_new_with_type(ti);
 }
 
+Object *object_new_propv(const char *typename,
+                         const char *path,
+                         const char *id,
+                         Error **errp,
+                         ...)
+{
+    va_list vargs;
+    Object *obj;
+
+    va_start(vargs, errp);
+    obj = object_new_proplist(typename, path, id, errp, vargs);
+    va_end(vargs);
+
+    return obj;
+}
+
+Object *object_new_proplist(const char *typename,
+                            const char *path,
+                            const char *id,
+                            Error **errp,
+                            va_list vargs)
+{
+    Object *obj;
+    const char *propname;
+
+    obj = object_new(typename);
+
+    if (object_class_is_abstract(object_get_class(obj))) {
+        error_setg(errp, "object type '%s' is abstract", typename);
+        goto error;
+    }
+
+    propname = va_arg(vargs, char *);
+    while (propname != NULL) {
+        const char *value = va_arg(vargs, char *);
+
+        g_assert(value != NULL);
+        object_property_parse(obj, value, propname, errp);
+        if (*errp) {
+            goto error;
+        }
+        propname = va_arg(vargs, char *);
+    }
+
+    object_property_add_child(container_get(object_get_root(), path),
+                              id, obj, errp);
+    if (*errp) {
+        goto error;
+    }
+
+    if (object_dynamic_cast(obj, TYPE_USER_CREATABLE)) {
+        user_creatable_complete(obj, errp);
+        if (*errp) {
+            object_property_del(container_get(object_get_root(), path),
+                                id, &error_abort);
+            goto error;
+        }
+    }
+
+    return obj;
+
+ error:
+    object_unref(obj);
+    return NULL;
+}
+
 Object *object_dynamic_cast(Object *obj, const char *typename)
 {
     if (obj && object_class_dynamic_cast(object_get_class(obj), typename)) {
diff --git a/tests/.gitignore b/tests/.gitignore
index 0dcb618..dc813c2 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -5,6 +5,7 @@ check-qjson
 check-qlist
 check-qstring
 check-qom-interface
+check-qom-proplist
 rcutorture
 test-aio
 test-bitops
diff --git a/tests/Makefile b/tests/Makefile
index 309e869..e0a831c 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -68,6 +68,8 @@ check-unit-y += tests/test-bitops$(EXESUF)
 check-unit-$(CONFIG_HAS_GLIB_SUBPROCESS_TESTS) += tests/test-qdev-global-props$(EXESUF)
 check-unit-y += tests/check-qom-interface$(EXESUF)
 gcov-files-check-qom-interface-y = qom/object.c
+check-unit-y += tests/check-qom-proplist$(EXESUF)
+gcov-files-check-qom-proplist-y = qom/object.c
 check-unit-y += tests/test-qemu-opts$(EXESUF)
 gcov-files-test-qemu-opts-y = qom/test-qemu-opts.c
 check-unit-y += tests/test-write-threshold$(EXESUF)
@@ -240,7 +242,7 @@ test-qapi-obj-y = tests/test-qapi-visit.o tests/test-qapi-types.o \
 
 $(test-obj-y): QEMU_INCLUDES += -Itests
 QEMU_CFLAGS += -I$(SRC_PATH)/tests
-qom-core-obj = qom/object.o qom/qom-qobject.o qom/container.o
+qom-core-obj = qom/object.o qom/qom-qobject.o qom/container.o qom/object_interfaces.o
 
 tests/check-qint$(EXESUF): tests/check-qint.o libqemuutil.a
 tests/check-qstring$(EXESUF): tests/check-qstring.o libqemuutil.a
@@ -249,6 +251,7 @@ tests/check-qlist$(EXESUF): tests/check-qlist.o libqemuutil.a
 tests/check-qfloat$(EXESUF): tests/check-qfloat.o libqemuutil.a
 tests/check-qjson$(EXESUF): tests/check-qjson.o libqemuutil.a libqemustub.a
 tests/check-qom-interface$(EXESUF): tests/check-qom-interface.o $(qom-core-obj) libqemuutil.a libqemustub.a
+tests/check-qom-proplist$(EXESUF): tests/check-qom-proplist.o $(qom-core-obj) libqemuutil.a libqemustub.a
 tests/test-coroutine$(EXESUF): tests/test-coroutine.o $(block-obj-y) libqemuutil.a libqemustub.a
 tests/test-aio$(EXESUF): tests/test-aio.o $(block-obj-y) libqemuutil.a libqemustub.a
 tests/test-rfifolock$(EXESUF): tests/test-rfifolock.o libqemuutil.a libqemustub.a
diff --git a/tests/check-qom-proplist.c b/tests/check-qom-proplist.c
new file mode 100644
index 0000000..9a02e4d
--- /dev/null
+++ b/tests/check-qom-proplist.c
@@ -0,0 +1,190 @@
+/*
+ * Copyright (C) 2015 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Author: Daniel P. Berrange <berrange@redhat.com>
+ */
+
+#include <glib.h>
+
+#include "qom/object.h"
+#include "qemu/module.h"
+
+
+#define TYPE_DUMMY "qemu:dummy"
+
+typedef struct DummyObject DummyObject;
+typedef struct DummyObjectClass DummyObjectClass;
+
+#define DUMMY_OBJECT(obj)                               \
+    OBJECT_CHECK(DummyObject, (obj), TYPE_DUMMY)
+
+struct DummyObject {
+    Object parent;
+
+    bool bv;
+    char *sv;
+};
+
+struct DummyObjectClass {
+    ObjectClass parent;
+};
+
+
+static void dummy_set_bv(Object *obj,
+                         bool value,
+                         Error **errp)
+{
+    DummyObject *dobj = DUMMY_OBJECT(obj);
+
+    dobj->bv = value;
+}
+
+static bool dummy_get_bv(Object *obj,
+                         Error **errp)
+{
+    DummyObject *dobj = DUMMY_OBJECT(obj);
+
+    return dobj->bv;
+}
+
+
+static void dummy_set_sv(Object *obj,
+                         const char *value,
+                         Error **errp)
+{
+    DummyObject *dobj = DUMMY_OBJECT(obj);
+
+    g_free(dobj->sv);
+    dobj->sv = g_strdup(value);
+}
+
+static char *dummy_get_sv(Object *obj,
+                          Error **errp)
+{
+    DummyObject *dobj = DUMMY_OBJECT(obj);
+
+    return g_strdup(dobj->sv);
+}
+
+
+static void dummy_init(Object *obj)
+{
+    object_property_add_bool(obj, "bv",
+                             dummy_get_bv,
+                             dummy_set_bv,
+                             NULL);
+    object_property_add_str(obj, "sv",
+                            dummy_get_sv,
+                            dummy_set_sv,
+                            NULL);
+}
+
+static void dummy_finalize(Object *obj)
+{
+    DummyObject *dobj = DUMMY_OBJECT(obj);
+
+    g_free(dobj->sv);
+}
+
+
+static const TypeInfo dummy_info = {
+    .name          = TYPE_DUMMY,
+    .parent        = TYPE_OBJECT,
+    .instance_size = sizeof(DummyObject),
+    .instance_init = dummy_init,
+    .instance_finalize = dummy_finalize,
+    .class_size = sizeof(DummyObjectClass),
+};
+
+static void test_dummy_createv(void)
+{
+    Error *err = NULL;
+    DummyObject *dobj = DUMMY_OBJECT(
+        object_new_propv(TYPE_DUMMY,
+                         "/objects",
+                         "dummy0",
+                         &err,
+                         "bv", "yes",
+                         "sv", "Hiss hiss hiss",
+                         NULL));
+
+    g_assert(dobj != NULL);
+    g_assert(err == NULL);
+    g_assert(g_str_equal(dobj->sv, "Hiss hiss hiss"));
+    g_assert(dobj->bv == true);
+
+    g_assert(object_resolve_path_component(
+                 container_get(object_get_root(),
+                               "/objects"),
+                 "dummy0") == OBJECT(dobj));
+
+    object_unparent(OBJECT(dobj));
+    object_unref(OBJECT(dobj));
+}
+
+
+static Object *new_helper(Error **errp,
+                          ...)
+{
+    va_list vargs;
+    Object *obj;
+
+    va_start(vargs, errp);
+    obj = object_new_proplist(TYPE_DUMMY,
+                              "/objects",
+                              "dummy0",
+                              errp,
+                              vargs);
+    va_end(vargs);
+    return obj;
+}
+
+static void test_dummy_createlist(void)
+{
+    Error *err = NULL;
+    DummyObject *dobj = DUMMY_OBJECT(
+        new_helper(&err,
+                   "bv", "yes",
+                   "sv", "Hiss hiss hiss",
+                   NULL));
+
+    g_assert(dobj != NULL);
+    g_assert(err == NULL);
+    g_assert(g_str_equal(dobj->sv, "Hiss hiss hiss"));
+    g_assert(dobj->bv == true);
+
+    g_assert(object_resolve_path_component(
+                 container_get(object_get_root(),
+                               "/objects"),
+                 "dummy0") == OBJECT(dobj));
+
+    object_unparent(OBJECT(dobj));
+    object_unref(OBJECT(dobj));
+}
+
+int main(int argc, char **argv)
+{
+    g_test_init(&argc, &argv, NULL);
+
+    module_call_init(MODULE_INIT_QOM);
+    type_register_static(&dummy_info);
+
+    g_test_add_func("/qom/proplist/createlist", test_dummy_createlist);
+    g_test_add_func("/qom/proplist/createv", test_dummy_createv);
+
+    return g_test_run();
+}
-- 
2.1.0

[Qemu-devel] [PATCH v2 5/7] qom: make enum string tables const-correct

[Daniel P. Berrange]

The enum string table parameters in various QOM/QAPI methods
are declared 'const char *strings[]'. This results in const
warnings if passed a variable that was declared as

   static const char * const strings[] = { .... };

Add the extra const annotation to the parameters, since
neither the string elements, nor the array itself should
ever be modified.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 include/hw/qdev-core.h      | 2 +-
 include/qapi/util.h         | 2 +-
 include/qapi/visitor-impl.h | 6 +++---
 include/qapi/visitor.h      | 2 +-
 include/qom/object.h        | 2 +-
 qapi/qapi-dealloc-visitor.c | 3 ++-
 qapi/qapi-util.c            | 2 +-
 qapi/qapi-visit-core.c      | 6 +++---
 qom/object.c                | 2 +-
 scripts/qapi-types.py       | 4 ++--
 10 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index 4e673f9..913963e 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -236,7 +236,7 @@ struct Property {
 struct PropertyInfo {
     const char *name;
     const char *description;
-    const char **enum_table;
+    const char * const *enum_table;
     int (*print)(DeviceState *dev, Property *prop, char *dest, size_t len);
     ObjectPropertyAccessor *get;
     ObjectPropertyAccessor *set;
diff --git a/include/qapi/util.h b/include/qapi/util.h
index de9238b..7ad26c0 100644
--- a/include/qapi/util.h
+++ b/include/qapi/util.h
@@ -11,7 +11,7 @@
 #ifndef QAPI_UTIL_H
 #define QAPI_UTIL_H
 
-int qapi_enum_parse(const char *lookup[], const char *buf,
+int qapi_enum_parse(const char * const lookup[], const char *buf,
                     int max, int def, Error **errp);
 
 #endif
diff --git a/include/qapi/visitor-impl.h b/include/qapi/visitor-impl.h
index 09bb0fd..f4a2f74 100644
--- a/include/qapi/visitor-impl.h
+++ b/include/qapi/visitor-impl.h
@@ -30,7 +30,7 @@ struct Visitor
     GenericList *(*next_list)(Visitor *v, GenericList **list, Error **errp);
     void (*end_list)(Visitor *v, Error **errp);
 
-    void (*type_enum)(Visitor *v, int *obj, const char *strings[],
+    void (*type_enum)(Visitor *v, int *obj, const char * const strings[],
                       const char *kind, const char *name, Error **errp);
     void (*get_next_type)(Visitor *v, int *kind, const int *qobjects,
                           const char *name, Error **errp);
@@ -59,9 +59,9 @@ struct Visitor
     void (*end_union)(Visitor *v, bool data_present, Error **errp);
 };
 
-void input_type_enum(Visitor *v, int *obj, const char *strings[],
+void input_type_enum(Visitor *v, int *obj, const char * const strings[],
                      const char *kind, const char *name, Error **errp);
-void output_type_enum(Visitor *v, int *obj, const char *strings[],
+void output_type_enum(Visitor *v, int *obj, const char * const strings[],
                       const char *kind, const char *name, Error **errp);
 
 #endif
diff --git a/include/qapi/visitor.h b/include/qapi/visitor.h
index 5934f59..00ba104 100644
--- a/include/qapi/visitor.h
+++ b/include/qapi/visitor.h
@@ -43,7 +43,7 @@ void visit_optional(Visitor *v, bool *present, const char *name,
                     Error **errp);
 void visit_get_next_type(Visitor *v, int *obj, const int *qtypes,
                          const char *name, Error **errp);
-void visit_type_enum(Visitor *v, int *obj, const char *strings[],
+void visit_type_enum(Visitor *v, int *obj, const char * const strings[],
                      const char *kind, const char *name, Error **errp);
 void visit_type_int(Visitor *v, int64_t *obj, const char *name, Error **errp);
 void visit_type_uint8(Visitor *v, uint8_t *obj, const char *name, Error **errp);
diff --git a/include/qom/object.h b/include/qom/object.h
index 6365b91..2c4e7c4 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -1017,7 +1017,7 @@ int64_t object_property_get_int(Object *obj, const char *name,
  * an enum).
  */
 int object_property_get_enum(Object *obj, const char *name,
-                             const char *strings[], Error **errp);
+                             const char * const strings[], Error **errp);
 
 /**
  * object_property_get_uint16List:
diff --git a/qapi/qapi-dealloc-visitor.c b/qapi/qapi-dealloc-visitor.c
index a14a1c7..d7f92c5 100644
--- a/qapi/qapi-dealloc-visitor.c
+++ b/qapi/qapi-dealloc-visitor.c
@@ -156,7 +156,8 @@ static void qapi_dealloc_type_size(Visitor *v, uint64_t *obj, const char *name,
 {
 }
 
-static void qapi_dealloc_type_enum(Visitor *v, int *obj, const char *strings[],
+static void qapi_dealloc_type_enum(Visitor *v, int *obj,
+                                   const char * const strings[],
                                    const char *kind, const char *name,
                                    Error **errp)
 {
diff --git a/qapi/qapi-util.c b/qapi/qapi-util.c
index 1d8fb96..bcdc94d 100644
--- a/qapi/qapi-util.c
+++ b/qapi/qapi-util.c
@@ -14,7 +14,7 @@
 #include "qapi/error.h"
 #include "qapi/util.h"
 
-int qapi_enum_parse(const char *lookup[], const char *buf,
+int qapi_enum_parse(const char * const lookup[], const char *buf,
                     int max, int def, Error **errp)
 {
     int i;
diff --git a/qapi/qapi-visit-core.c b/qapi/qapi-visit-core.c
index b66b93a..a18ba16 100644
--- a/qapi/qapi-visit-core.c
+++ b/qapi/qapi-visit-core.c
@@ -89,7 +89,7 @@ void visit_get_next_type(Visitor *v, int *obj, const int *qtypes,
     }
 }
 
-void visit_type_enum(Visitor *v, int *obj, const char *strings[],
+void visit_type_enum(Visitor *v, int *obj, const char * const strings[],
                      const char *kind, const char *name, Error **errp)
 {
     v->type_enum(v, obj, strings, kind, name, errp);
@@ -260,7 +260,7 @@ void visit_type_number(Visitor *v, double *obj, const char *name, Error **errp)
     v->type_number(v, obj, name, errp);
 }
 
-void output_type_enum(Visitor *v, int *obj, const char *strings[],
+void output_type_enum(Visitor *v, int *obj, const char * const strings[],
                       const char *kind, const char *name,
                       Error **errp)
 {
@@ -279,7 +279,7 @@ void output_type_enum(Visitor *v, int *obj, const char *strings[],
     visit_type_str(v, &enum_str, name, errp);
 }
 
-void input_type_enum(Visitor *v, int *obj, const char *strings[],
+void input_type_enum(Visitor *v, int *obj, const char * const strings[],
                      const char *kind, const char *name,
                      Error **errp)
 {
diff --git a/qom/object.c b/qom/object.c
index 8927261..48ab7c3 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -1028,7 +1028,7 @@ int64_t object_property_get_int(Object *obj, const char *name,
 }
 
 int object_property_get_enum(Object *obj, const char *name,
-                             const char *strings[], Error **errp)
+                             const char * const strings[], Error **errp)
 {
     StringOutputVisitor *sov;
     StringInputVisitor *siv;
diff --git a/scripts/qapi-types.py b/scripts/qapi-types.py
index db87218..c8d6db6 100644
--- a/scripts/qapi-types.py
+++ b/scripts/qapi-types.py
@@ -118,7 +118,7 @@ struct %(name)s
 
 def generate_enum_lookup(name, values):
     ret = mcgen('''
-const char *%(name)s_lookup[] = {
+const char * const %(name)s_lookup[] = {
 ''',
                          name=name)
     i = 0
@@ -140,7 +140,7 @@ const char *%(name)s_lookup[] = {
 
 def generate_enum(name, values):
     lookup_decl = mcgen('''
-extern const char *%(name)s_lookup[];
+extern const char * const %(name)s_lookup[];
 ''',
                 name=name)
 
-- 
2.1.0

[Qemu-devel] [PATCH v2 6/7] qom: add a object_property_add_enum helper method

[Daniel P. Berrange]

A QOM property can be parsed as enum using the visit_type_enum()
helper method, but this forces callers to use the more complex
generic object_property_add() method when registering it. It
also requires that users of that object have access to the
string map when they want to read the property value.

This patch introduces a specialized object_property_add_enum()
method which simplifies the use of enum properties, so the
setters/getters directly get passed the int value.

  typedef enum {
     MYDEV_TYPE_FROG,
     MYDEV_TYPE_ALLIGATOR,
     MYDEV_TYPE_PLATYPUS,

     MYDEV_TYPE_LAST
  } MyDevType;

Then provide a table of enum <-> string mappings

  static const char *const mydevtypemap[MYDEV_TYPE_LAST + 1] = {
     [MYDEV_TYPE_FROG] = "frog",
     [MYDEV_TYPE_ALLIGATOR] = "alligator",
     [MYDEV_TYPE_PLATYPUS] = "platypus",
     [MYDEV_TYPE_LAST] = NULL,
  };

Assuming an object struct of

   typedef struct {
      Object parent;
      MyDevType devtype;
      ...other fields...
   } MyDev;

The property can then be registered as follows:

   static int mydev_prop_get_devtype(Object *obj,
                                     Error **errp G_GNUC_UNUSED)
   {
       MyDev *dev = MYDEV(obj);

       return dev->devtype;
   }

   static void mydev_prop_set_devtype(Object *obj,
                                      int value,
                                      Error **errp G_GNUC_UNUSED)
   {
       MyDev *dev = MYDEV(obj);

       dev->endpoint = value;
   }

   object_property_add_enum(obj, "devtype",
                            mydevtypemap, "MyDevType",
                            mydev_prop_get_devtype,
                            mydev_prop_set_devtype,
                            NULL);

Note there is no need to check the range of 'value' in
the setter, because the string->enum conversion code will
have already done that and reported an error as required.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 include/qom/object.h       | 19 ++++++++++++
 qom/object.c               | 58 ++++++++++++++++++++++++++++++++++++
 tests/check-qom-proplist.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 151 insertions(+)

diff --git a/include/qom/object.h b/include/qom/object.h
index 2c4e7c4..63002d7 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -1268,6 +1268,25 @@ void object_property_add_bool(Object *obj, const char *name,
                               Error **errp);
 
 /**
+ * object_property_add_enum:
+ * @obj: the object to add a property to
+ * @name: the name of the property
+ * @typename: the name of the enum data type
+ * @get: the getter or NULL if the property is write-only.
+ * @set: the setter or NULL if the property is read-only
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Add a enum property using getters/setters.  This function will add a
+ * property of type 'enum'.
+ */
+void object_property_add_enum(Object *obj, const char *name,
+                              const char *typename,
+                              const char * const *strings,
+                              int (*get)(Object *, Error **),
+                              void (*set)(Object *, int, Error **),
+                              Error **errp);
+
+/**
  * object_property_add_tm:
  * @obj: the object to add a property to
  * @name: the name of the property
diff --git a/qom/object.c b/qom/object.c
index 48ab7c3..e72e9b2 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -1610,6 +1610,64 @@ void object_property_add_bool(Object *obj, const char *name,
     }
 }
 
+typedef struct EnumProperty {
+    const char * const *strings;
+    int (*get)(Object *, Error **);
+    void (*set)(Object *, int, Error **);
+} EnumProperty;
+
+static void property_get_enum(Object *obj, Visitor *v, void *opaque,
+                              const char *name, Error **errp)
+{
+    EnumProperty *prop = opaque;
+    int value;
+
+    value = prop->get(obj, errp);
+    visit_type_enum(v, &value, prop->strings, NULL, name, errp);
+}
+
+static void property_set_enum(Object *obj, Visitor *v, void *opaque,
+                              const char *name, Error **errp)
+{
+    EnumProperty *prop = opaque;
+    int value;
+
+    visit_type_enum(v, &value, prop->strings, NULL, name, errp);
+    prop->set(obj, value, errp);
+}
+
+static void property_release_enum(Object *obj, const char *name,
+                                  void *opaque)
+{
+    EnumProperty *prop = opaque;
+    g_free(prop);
+}
+
+void object_property_add_enum(Object *obj, const char *name,
+                              const char *typename,
+                              const char * const *strings,
+                              int (*get)(Object *, Error **),
+                              void (*set)(Object *, int, Error **),
+                              Error **errp)
+{
+    Error *local_err = NULL;
+    EnumProperty *prop = g_malloc0(sizeof(*prop));
+
+    prop->strings = strings;
+    prop->get = get;
+    prop->set = set;
+
+    object_property_add(obj, name, typename,
+                        get ? property_get_enum : NULL,
+                        set ? property_set_enum : NULL,
+                        property_release_enum,
+                        prop, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        g_free(prop);
+    }
+}
+
 typedef struct TMProperty {
     void (*get)(Object *, struct tm *, Error **);
 } TMProperty;
diff --git a/tests/check-qom-proplist.c b/tests/check-qom-proplist.c
index 9a02e4d..15f4933 100644
--- a/tests/check-qom-proplist.c
+++ b/tests/check-qom-proplist.c
@@ -32,10 +32,28 @@ typedef struct DummyObjectClass DummyObjectClass;
 #define DUMMY_OBJECT(obj)                               \
     OBJECT_CHECK(DummyObject, (obj), TYPE_DUMMY)
 
+typedef enum DummyAnimal DummyAnimal;
+
+enum DummyAnimal {
+    DUMMY_FROG,
+    DUMMY_ALLIGATOR,
+    DUMMY_PLATYPUS,
+
+    DUMMY_LAST,
+};
+
+static const char *const dummyanimalmap[DUMMY_LAST + 1] = {
+    [DUMMY_FROG] = "frog",
+    [DUMMY_ALLIGATOR] = "alligator",
+    [DUMMY_PLATYPUS] = "platypus",
+    [DUMMY_LAST] = NULL,
+};
+
 struct DummyObject {
     Object parent;
 
     bool bv;
+    DummyAnimal av;
     char *sv;
 };
 
@@ -62,6 +80,24 @@ static bool dummy_get_bv(Object *obj,
 }
 
 
+static void dummy_set_av(Object *obj,
+                         int value,
+                         Error **errp)
+{
+    DummyObject *dobj = DUMMY_OBJECT(obj);
+
+    dobj->av = value;
+}
+
+static int dummy_get_av(Object *obj,
+                        Error **errp)
+{
+    DummyObject *dobj = DUMMY_OBJECT(obj);
+
+    return dobj->av;
+}
+
+
 static void dummy_set_sv(Object *obj,
                          const char *value,
                          Error **errp)
@@ -91,6 +127,12 @@ static void dummy_init(Object *obj)
                             dummy_get_sv,
                             dummy_set_sv,
                             NULL);
+    object_property_add_enum(obj, "av",
+                             "DummyAnimal",
+                             dummyanimalmap,
+                             dummy_get_av,
+                             dummy_set_av,
+                             NULL);
 }
 
 static void dummy_finalize(Object *obj)
@@ -120,12 +162,14 @@ static void test_dummy_createv(void)
                          &err,
                          "bv", "yes",
                          "sv", "Hiss hiss hiss",
+                         "av", "platypus",
                          NULL));
 
     g_assert(dobj != NULL);
     g_assert(err == NULL);
     g_assert(g_str_equal(dobj->sv, "Hiss hiss hiss"));
     g_assert(dobj->bv == true);
+    g_assert(dobj->av == DUMMY_PLATYPUS);
 
     g_assert(object_resolve_path_component(
                  container_get(object_get_root(),
@@ -160,12 +204,14 @@ static void test_dummy_createlist(void)
         new_helper(&err,
                    "bv", "yes",
                    "sv", "Hiss hiss hiss",
+                   "av", "platypus",
                    NULL));
 
     g_assert(dobj != NULL);
     g_assert(err == NULL);
     g_assert(g_str_equal(dobj->sv, "Hiss hiss hiss"));
     g_assert(dobj->bv == true);
+    g_assert(dobj->av == DUMMY_PLATYPUS);
 
     g_assert(object_resolve_path_component(
                  container_get(object_get_root(),
@@ -176,6 +222,33 @@ static void test_dummy_createlist(void)
     object_unref(OBJECT(dobj));
 }
 
+static void test_dummy_badenum(void)
+{
+    Error *err = NULL;
+    DummyObject *dobj = DUMMY_OBJECT(
+        object_new_propv(TYPE_DUMMY,
+                         "/objects",
+                         "dummy0",
+                         &err,
+                         "bv", "yes",
+                         "sv", "Hiss hiss hiss",
+                         "av", "yeti",
+                         NULL));
+
+    g_assert(dobj == NULL);
+    g_assert(err != NULL);
+    g_assert(g_str_equal(error_get_pretty(err),
+                         "Invalid parameter 'yeti'"));
+
+    g_assert(object_resolve_path_component(
+                 container_get(object_get_root(),
+                               "/objects"),
+                 "dummy0") == NULL);
+
+    error_free(err);
+}
+
+
 int main(int argc, char **argv)
 {
     g_test_init(&argc, &argv, NULL);
@@ -185,6 +258,7 @@ int main(int argc, char **argv)
 
     g_test_add_func("/qom/proplist/createlist", test_dummy_createlist);
     g_test_add_func("/qom/proplist/createv", test_dummy_createv);
+    g_test_add_func("/qom/proplist/badenum", test_dummy_badenum);
 
     return g_test_run();
 }
-- 
2.1.0

[Qemu-devel] [PATCH v2 7/7] qom: don't pass string table to object_get_enum method

[Daniel P. Berrange]

Now that properties can be explicitly registered as an enum
type, there is no need to pass the string table to the
object_get_enum method. The object property registration
already has a pointer to the string table.

In changing this method signature, the hostmem backend object
has to be converted to use the new enum property registration
code, which simplifies it somewhat.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 backends/hostmem.c         | 22 ++++++++--------------
 include/qom/object.h       |  4 ++--
 numa.c                     |  2 +-
 qom/object.c               | 32 ++++++++++++++++++++++++--------
 tests/check-qom-proplist.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 79 insertions(+), 25 deletions(-)

diff --git a/backends/hostmem.c b/backends/hostmem.c
index f6db33c..7d74be0 100644
--- a/backends/hostmem.c
+++ b/backends/hostmem.c
@@ -113,24 +113,17 @@ host_memory_backend_set_host_nodes(Object *obj, Visitor *v, void *opaque,
 #endif
 }
 
-static void
-host_memory_backend_get_policy(Object *obj, Visitor *v, void *opaque,
-                               const char *name, Error **errp)
+static int
+host_memory_backend_get_policy(Object *obj, Error **errp G_GNUC_UNUSED)
 {
     HostMemoryBackend *backend = MEMORY_BACKEND(obj);
-    int policy = backend->policy;
-
-    visit_type_enum(v, &policy, HostMemPolicy_lookup, NULL, name, errp);
+    return backend->policy;
 }
 
 static void
-host_memory_backend_set_policy(Object *obj, Visitor *v, void *opaque,
-                               const char *name, Error **errp)
+host_memory_backend_set_policy(Object *obj, int policy, Error **errp)
 {
     HostMemoryBackend *backend = MEMORY_BACKEND(obj);
-    int policy;
-
-    visit_type_enum(v, &policy, HostMemPolicy_lookup, NULL, name, errp);
     backend->policy = policy;
 
 #ifndef CONFIG_NUMA
@@ -252,9 +245,10 @@ static void host_memory_backend_init(Object *obj)
     object_property_add(obj, "host-nodes", "int",
                         host_memory_backend_get_host_nodes,
                         host_memory_backend_set_host_nodes, NULL, NULL, NULL);
-    object_property_add(obj, "policy", "HostMemPolicy",
-                        host_memory_backend_get_policy,
-                        host_memory_backend_set_policy, NULL, NULL, NULL);
+    object_property_add_enum(obj, "policy", "HostMemPolicy",
+                             HostMemPolicy_lookup,
+                             host_memory_backend_get_policy,
+                             host_memory_backend_set_policy, NULL);
 }
 
 MemoryRegion *
diff --git a/include/qom/object.h b/include/qom/object.h
index 63002d7..b68a3a9 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -1009,7 +1009,7 @@ int64_t object_property_get_int(Object *obj, const char *name,
  * object_property_get_enum:
  * @obj: the object
  * @name: the name of the property
- * @strings: strings corresponding to enums
+ * @typename: the name of the enum data type
  * @errp: returns an error if this function fails
  *
  * Returns: the value of the property, converted to an integer, or
@@ -1017,7 +1017,7 @@ int64_t object_property_get_int(Object *obj, const char *name,
  * an enum).
  */
 int object_property_get_enum(Object *obj, const char *name,
-                             const char * const strings[], Error **errp);
+                             const char *typename, Error **errp);
 
 /**
  * object_property_get_uint16List:
diff --git a/numa.c b/numa.c
index c975fb2..a64279a 100644
--- a/numa.c
+++ b/numa.c
@@ -457,7 +457,7 @@ static int query_memdev(Object *obj, void *opaque)
 
         m->value->policy = object_property_get_enum(obj,
                                                     "policy",
-                                                    HostMemPolicy_lookup,
+                                                    "HostMemPolicy",
                                                     &err);
         if (err) {
             goto error;
diff --git a/qom/object.c b/qom/object.c
index e72e9b2..82e5079 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -1027,13 +1027,35 @@ int64_t object_property_get_int(Object *obj, const char *name,
     return retval;
 }
 
+typedef struct EnumProperty {
+    const char * const *strings;
+    int (*get)(Object *, Error **);
+    void (*set)(Object *, int, Error **);
+} EnumProperty;
+
+
 int object_property_get_enum(Object *obj, const char *name,
-                             const char * const strings[], Error **errp)
+                             const char *typename, Error **errp)
 {
     StringOutputVisitor *sov;
     StringInputVisitor *siv;
     char *str;
     int ret;
+    ObjectProperty *prop = object_property_find(obj, name, errp);
+    EnumProperty *enumprop;
+
+    if (prop == NULL) {
+        return 0;
+    }
+
+    if (!g_str_equal(prop->type, typename)) {
+        error_setg(errp, "Property %s on %s is not '%s' enum type",
+                   name, object_class_get_name(
+                       object_get_class(obj)), typename);
+        return 0;
+    }
+
+    enumprop = prop->opaque;
 
     sov = string_output_visitor_new(false);
     object_property_get(obj, string_output_get_visitor(sov), name, errp);
@@ -1041,7 +1063,7 @@ int object_property_get_enum(Object *obj, const char *name,
     siv = string_input_visitor_new(str);
     string_output_visitor_cleanup(sov);
     visit_type_enum(string_input_get_visitor(siv),
-                    &ret, strings, NULL, name, errp);
+                    &ret, enumprop->strings, NULL, name, errp);
 
     g_free(str);
     string_input_visitor_cleanup(siv);
@@ -1610,12 +1632,6 @@ void object_property_add_bool(Object *obj, const char *name,
     }
 }
 
-typedef struct EnumProperty {
-    const char * const *strings;
-    int (*get)(Object *, Error **);
-    void (*set)(Object *, int, Error **);
-} EnumProperty;
-
 static void property_get_enum(Object *obj, Visitor *v, void *opaque,
                               const char *name, Error **errp)
 {
diff --git a/tests/check-qom-proplist.c b/tests/check-qom-proplist.c
index 15f4933..0ad073f 100644
--- a/tests/check-qom-proplist.c
+++ b/tests/check-qom-proplist.c
@@ -249,6 +249,49 @@ static void test_dummy_badenum(void)
 }
 
 
+
+static void test_dummy_getenum(void)
+{
+    Error *err = NULL;
+    int val;
+    DummyObject *dobj = DUMMY_OBJECT(
+        object_new_propv(TYPE_DUMMY,
+                         "/objects",
+                         "dummy0",
+                         &err,
+                         "av", "platypus",
+                         NULL));
+
+    g_assert(dobj != NULL);
+    g_assert(err == NULL);
+    g_assert(dobj->av == DUMMY_PLATYPUS);
+
+    val = object_property_get_enum(OBJECT(dobj),
+                                   "av",
+                                   "DummyAnimal",
+                                   &err);
+    g_assert(err == NULL);
+    g_assert(val == DUMMY_PLATYPUS);
+
+    /* A bad enum type name */
+    val = object_property_get_enum(OBJECT(dobj),
+                                   "av",
+                                   "BadAnimal",
+                                   &err);
+    g_assert(err != NULL);
+    error_free(err);
+    err = NULL;
+
+    /* A non-enum property name */
+    val = object_property_get_enum(OBJECT(dobj),
+                                   "iv",
+                                   "DummyAnimal",
+                                   &err);
+    g_assert(err != NULL);
+    error_free(err);
+}
+
+
 int main(int argc, char **argv)
 {
     g_test_init(&argc, &argv, NULL);
@@ -259,6 +302,7 @@ int main(int argc, char **argv)
     g_test_add_func("/qom/proplist/createlist", test_dummy_createlist);
     g_test_add_func("/qom/proplist/createv", test_dummy_createv);
     g_test_add_func("/qom/proplist/badenum", test_dummy_badenum);
+    g_test_add_func("/qom/proplist/getenum", test_dummy_getenum);
 
     return g_test_run();
 }
-- 
2.1.0

Re: [Qemu-devel] [PATCH v2 6/7] qom: add a object_property_add_enum helper method

[Daniel P. Berrange]

On Thu, Apr 30, 2015 at 04:46:37PM +0100, Daniel P. Berrange wrote:
> A QOM property can be parsed as enum using the visit_type_enum()
> helper method, but this forces callers to use the more complex
> generic object_property_add() method when registering it. It
> also requires that users of that object have access to the
> string map when they want to read the property value.
> 
> This patch introduces a specialized object_property_add_enum()
> method which simplifies the use of enum properties, so the
> setters/getters directly get passed the int value.
> 
>   typedef enum {
>      MYDEV_TYPE_FROG,
>      MYDEV_TYPE_ALLIGATOR,
>      MYDEV_TYPE_PLATYPUS,
> 
>      MYDEV_TYPE_LAST
>   } MyDevType;
> 
> Then provide a table of enum <-> string mappings
> 
>   static const char *const mydevtypemap[MYDEV_TYPE_LAST + 1] = {
>      [MYDEV_TYPE_FROG] = "frog",
>      [MYDEV_TYPE_ALLIGATOR] = "alligator",
>      [MYDEV_TYPE_PLATYPUS] = "platypus",
>      [MYDEV_TYPE_LAST] = NULL,
>   };
> 
> Assuming an object struct of
> 
>    typedef struct {
>       Object parent;
>       MyDevType devtype;
>       ...other fields...
>    } MyDev;
> 
> The property can then be registered as follows:
> 
>    static int mydev_prop_get_devtype(Object *obj,
>                                      Error **errp G_GNUC_UNUSED)
>    {
>        MyDev *dev = MYDEV(obj);
> 
>        return dev->devtype;
>    }
> 
>    static void mydev_prop_set_devtype(Object *obj,
>                                       int value,
>                                       Error **errp G_GNUC_UNUSED)
>    {
>        MyDev *dev = MYDEV(obj);
> 
>        dev->endpoint = value;
>    }
> 
>    object_property_add_enum(obj, "devtype",
>                             mydevtypemap, "MyDevType",
>                             mydev_prop_get_devtype,
>                             mydev_prop_set_devtype,
>                             NULL);
> 
> Note there is no need to check the range of 'value' in
> the setter, because the string->enum conversion code will
> have already done that and reported an error as required.
> 
> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
> ---
>  include/qom/object.h       | 19 ++++++++++++
>  qom/object.c               | 58 ++++++++++++++++++++++++++++++++++++
>  tests/check-qom-proplist.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 151 insertions(+)


> diff --git a/tests/check-qom-proplist.c b/tests/check-qom-proplist.c
> index 9a02e4d..15f4933 100644
> --- a/tests/check-qom-proplist.c
> +++ b/tests/check-qom-proplist.c
> +static void test_dummy_badenum(void)
> +{
> +    Error *err = NULL;
> +    DummyObject *dobj = DUMMY_OBJECT(
> +        object_new_propv(TYPE_DUMMY,
> +                         "/objects",
> +                         "dummy0",
> +                         &err,
> +                         "bv", "yes",
> +                         "sv", "Hiss hiss hiss",
> +                         "av", "yeti",
> +                         NULL));

Opps, this won't compile as I forgot to update the 2nd arg. Will
send a v3

Regards,
Daniel
-- 
|: http://berrange.com      -o-    http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org              -o-             http://virt-manager.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org       -o-       http://live.gnome.org/gtk-vnc :|