Re: [Qemu-devel] [PATCH 1/3] qom-qobject: introduce object_property_{g, s}et_ptr

[Paolo Bonzini]

On 21/02/2017 11:42, Paolo Bonzini wrote:
> The functions simplify the handling of QOM properties whose type
> is a QAPI struct.  They go through a QObject just like the other
> functions that access a QOM property through its C type.
> 
> Like QAPI_CLONE, the functions are wrapped by macros that take a
> QAPI type name and use it to build the name of a visitor function.
> 
> Signed-off-by: Paolo Bonzini <address@hidden>
> ---
>  include/qom/qom-qobject.h               |  68 ++++++++++++
>  qom/qom-qobject.c                       |  49 +++++++++
>  tests/Makefile.include                  |   2 +-
>  tests/check-qom-proplist.c              | 185 
> +++++++++++++++++++++++++++++++-
>  tests/qapi-schema/qapi-schema-test.json |   8 ++
>  5 files changed, 309 insertions(+), 3 deletions(-)

Missing hunk:

diff --git a/tests/qapi-schema/qapi-schema-test.out 
b/tests/qapi-schema/qapi-schema-test.out
index bc8d496..d3a2990 100644
--- a/tests/qapi-schema/qapi-schema-test.out
+++ b/tests/qapi-schema/qapi-schema-test.out
@@ -107,6 +107,9 @@ object UserDefOne
     base UserDefZero
     member string: str optional=False
     member enum1: EnumOne optional=True
+object UserDefOneMore
+    base UserDefOne
+    member boolean: bool optional=False
 object UserDefOptions
     member i64: intList optional=True
     member u64: uint64List optional=True
@@ -283,6 +286,9 @@ for testing override of default naming heuristic
 doc symbol=UserDefOne expr=('struct', 'UserDefOne')
     body=
 for testing nested structs
+doc symbol=UserDefOneMore expr=('struct', 'UserDefOneMore')
+    body=
+for testing nested structs
 doc symbol=EnumOne expr=('enum', 'EnumOne')
 doc symbol=UserDefZero expr=('struct', 'UserDefZero')
 doc symbol=UserDefTwoDictDict expr=('struct', 'UserDefTwoDictDict')

Paolo

> diff --git a/include/qom/qom-qobject.h b/include/qom/qom-qobject.h
> index 77cd717..ff1d307 100644
> --- a/include/qom/qom-qobject.h
> +++ b/include/qom/qom-qobject.h
> @@ -39,4 +39,72 @@ struct QObject *object_property_get_qobject(Object *obj, 
> const char *name,
>  void object_property_set_qobject(Object *obj, struct QObject *qobj,
>                                   const char *name, struct Error **errp);
>  
> +/**
> + * object_property_get_ptr:
> + * @obj: the object
> + * @ptr: The C struct that will be written to the property.
> + * @name: the name of the property
> + * @visit_type: the visitor function for @ptr's type.
> + * @errp: returns an error if this function fails
> + *
> + * Return: the value of an object's property, unmarshaled into a C object
> + * through a QAPI type visitor, or NULL if an error occurs.
> + */
> +void *object_property_get_ptr(Object *obj, const char *name,
> +                              void (*visit_type)(Visitor *, const char *,
> +                                                 void **, Error **),
> +                              Error **errp);
> +
> +/**
> + * OBJECT_PROPERTY_GET_PTR:
> + * @obj: the object
> + * @ptr: The C struct that will be written to the property.
> + * @name: the name of the property
> + * @type: the name of the C struct type pointed to by @ptr.
> + * @errp: returns an error if this function fails
> + *
> + * Return: the value of an object's property, unmarshaled into a C object
> + * through a QAPI type visitor, or NULL if an error occurs.
> + */
> +#define OBJECT_PROPERTY_GET_PTR(obj, name, type, errp)                      \
> +    ((type *)                                                               \
> +     object_property_get_ptr(obj, name,                                     \
> +                             (void (*)(Visitor *, const char *, void**,     \
> +                                       Error **))visit_type_ ## type,       \
> +                             errp))
> +
> +/**
> + * object_property_set_ptr:
> + * @obj: the object
> + * @ptr: The C struct that will be written to the property.
> + * @name: the name of the property
> + * @visit_type: the visitor function for @ptr's type.
> + * @errp: returns an error if this function fails
> + *
> + * Sets an object's property to a C object's value, using a QAPI
> + * type visitor to marshal the C struct into the object.
> + */
> +void object_property_set_ptr(Object *obj, void *ptr, const char *name,
> +                             void (*visit_type)(Visitor *, const char *,
> +                                                void **, Error **),
> +                             Error **errp);
> +
> +/**
> + * OBJECT_PROPERTY_SET_PTR:
> + * @obj: the object
> + * @ptr: The C struct that will be written to the property.
> + * @name: the name of the property
> + * @type: the name of the C struct type pointed to by @ptr.
> + * @errp: returns an error if this function fails
> + *
> + * Sets an object's property to a C object's value, using a QAPI
> + * type visitor to marshal the C struct into the object.
> + */
> +#define OBJECT_PROPERTY_SET_PTR(obj, ptr, name, type, errp)                 \
> +    object_property_set_ptr(obj, ptr + type_check(type, typeof(*ptr)),      \
> +                            name,                                           \
> +                            (void (*)(Visitor *, const char *, void**,      \
> +                                      Error **))visit_type_ ## type,        \
> +                            errp)
> +
>  #endif
> diff --git a/qom/qom-qobject.c b/qom/qom-qobject.c
> index 447e4a0..09a12e0 100644
> --- a/qom/qom-qobject.c
> +++ b/qom/qom-qobject.c
> @@ -44,3 +44,52 @@ QObject *object_property_get_qobject(Object *obj, const 
> char *name,
>      visit_free(v);
>      return ret;
>  }
> +
> +void object_property_set_ptr(Object *obj, void *ptr, const char *name,
> +                             void (*visit_type)(Visitor *, const char *, 
> void **, Error **),
> +                             Error **errp)
> +{
> +    Error *local_err = NULL;
> +    QObject *ret = NULL;
> +    Visitor *v;
> +    v = qobject_output_visitor_new(&ret);
> +    visit_type(v, name, &ptr, &local_err);
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +        visit_free(v);
> +        return;
> +    }
> +    visit_complete(v, &ret);
> +    visit_free(v);
> +
> +    /* Do not use object_property_set_qobject until we switch it
> +     * to use qobject_input_visitor_new in strict mode.  See the
> +     * /qom/proplist/get-set-ptr/contravariant unit test.
> +     */
> +    v = qobject_input_visitor_new(ret, true);
> +    object_property_set(obj, v, name, errp);
> +    visit_free(v);
> +    qobject_decref(ret);
> +}
> +
> +void *object_property_get_ptr(Object *obj, const char *name,
> +                              void (*visit_type)(Visitor *, const char *, 
> void **, Error **),
> +                              Error **errp)
> +{
> +    QObject *ret;
> +    Visitor *v;
> +    void *ptr = NULL;
> +
> +    ret = object_property_get_qobject(obj, name, errp);
> +    if (!ret) {
> +        return NULL;
> +    }
> +
> +    /* Do not enable strict mode to allow passing covariant
> +     * data types.
> +     */
> +    v = qobject_input_visitor_new(ret, false);
> +    visit_type(v, name, &ptr, errp);
> +    qobject_decref(ret);
> +    return ptr;
> +}
> diff --git a/tests/Makefile.include b/tests/Makefile.include
> index 634394a..9de910b 100644
> --- a/tests/Makefile.include
> +++ b/tests/Makefile.include
> @@ -515,7 +515,7 @@ tests/check-qfloat$(EXESUF): tests/check-qfloat.o 
> $(test-util-obj-y)
>  tests/check-qnull$(EXESUF): tests/check-qnull.o $(test-util-obj-y)
>  tests/check-qjson$(EXESUF): tests/check-qjson.o $(test-util-obj-y)
>  tests/check-qom-interface$(EXESUF): tests/check-qom-interface.o 
> $(test-qom-obj-y)
> -tests/check-qom-proplist$(EXESUF): tests/check-qom-proplist.o 
> $(test-qom-obj-y)
> +tests/check-qom-proplist$(EXESUF): tests/check-qom-proplist.o 
> $(test-qom-obj-y) $(test-qapi-obj-y)
>  
>  tests/test-char$(EXESUF): tests/test-char.o qemu-timer.o \
>       $(test-util-obj-y) $(qtest-obj-y) $(test-block-obj-y) $(chardev-obj-y)
> diff --git a/tests/check-qom-proplist.c b/tests/check-qom-proplist.c
> index a16cefc..e0ad880 100644
> --- a/tests/check-qom-proplist.c
> +++ b/tests/check-qom-proplist.c
> @@ -22,8 +22,11 @@
>  
>  #include "qapi/error.h"
>  #include "qom/object.h"
> +#include "qom/qom-qobject.h"
>  #include "qemu/module.h"
>  
> +#include "test-qapi-types.h"
> +#include "test-qapi-visit.h"
>  
>  #define TYPE_DUMMY "qemu-dummy"
>  
> @@ -56,6 +59,8 @@ struct DummyObject {
>      bool bv;
>      DummyAnimal av;
>      char *sv;
> +
> +    UserDefOne *qv;
>  };
>  
>  struct DummyObjectClass {
> @@ -120,12 +125,42 @@ static char *dummy_get_sv(Object *obj,
>  
>  static void dummy_init(Object *obj)
>  {
> +    DummyObject *dobj = DUMMY_OBJECT(obj);
> +
>      object_property_add_bool(obj, "bv",
>                               dummy_get_bv,
>                               dummy_set_bv,
>                               NULL);
> +    dobj->qv = g_new0(UserDefOne, 1);
> +    dobj->qv->string = g_strdup("dummy string");
> +}
> +
> +
> +static void dummy_get_qv(Object *obj, Visitor *v, const char *name,
> +                         void *opaque, Error **errp)
> +{
> +    DummyObject *dobj = DUMMY_OBJECT(obj);
> +
> +    visit_type_UserDefOne(v, name, &dobj->qv, errp);
>  }
>  
> +static void dummy_set_qv(Object *obj, Visitor *v, const char *name,
> +                         void *opaque, Error **errp)
> +{
> +    DummyObject *dobj = DUMMY_OBJECT(obj);
> +    UserDefOne *qv = NULL;
> +    Error *local_err = NULL;
> +
> +    visit_type_UserDefOne(v, name, &qv, &local_err);
> +    if (local_err) {
> +        g_assert(qv == NULL);
> +        error_propagate(errp, local_err);
> +        return;
> +    }
> +
> +    qapi_free_UserDefOne(dobj->qv);
> +    dobj->qv = qv;
> +}
>  
>  static void dummy_class_init(ObjectClass *cls, void *data)
>  {
> @@ -143,6 +178,13 @@ static void dummy_class_init(ObjectClass *cls, void 
> *data)
>                                     dummy_get_av,
>                                     dummy_set_av,
>                                     NULL);
> +    object_class_property_add(cls, "qv",
> +                              "UserDefOne",
> +                              dummy_get_qv,
> +                              dummy_set_qv,
> +                              NULL,
> +                              NULL,
> +                              NULL);
>  }
>  
>  
> @@ -151,9 +193,9 @@ static void dummy_finalize(Object *obj)
>      DummyObject *dobj = DUMMY_OBJECT(obj);
>  
>      g_free(dobj->sv);
> +    qapi_free_UserDefOne(dobj->qv);
>  }
>  
> -
>  static const TypeInfo dummy_info = {
>      .name          = TYPE_DUMMY,
>      .parent        = TYPE_OBJECT,
> @@ -473,7 +515,8 @@ static void test_dummy_iterator(void)
>  
>      ObjectProperty *prop;
>      ObjectPropertyIterator iter;
> -    bool seenbv = false, seensv = false, seenav = false, seentype;
> +    bool seenbv = false, seensv = false, seenav = false;
> +    bool seenqv = false, seentype = false;
>  
>      object_property_iter_init(&iter, OBJECT(dobj));
>      while ((prop = object_property_iter_next(&iter))) {
> @@ -483,6 +526,8 @@ static void test_dummy_iterator(void)
>              seensv = true;
>          } else if (g_str_equal(prop->name, "av")) {
>              seenav = true;
> +        } else if (g_str_equal(prop->name, "qv")) {
> +            seenqv = true;
>          } else if (g_str_equal(prop->name, "type")) {
>              /* This prop comes from the base Object class */
>              seentype = true;
> @@ -494,6 +539,7 @@ static void test_dummy_iterator(void)
>      g_assert(seenbv);
>      g_assert(seenav);
>      g_assert(seensv);
> +    g_assert(seenqv);
>      g_assert(seentype);
>  
>      object_unparent(OBJECT(dobj));
> @@ -513,6 +559,137 @@ static void test_dummy_delchild(void)
>      object_unparent(OBJECT(dev));
>  }
>  
> +static void test_dummy_get_set_ptr_struct(void)
> +{
> +    DummyObject *dobj = DUMMY_OBJECT(object_new(TYPE_DUMMY));
> +    Error *local_err = NULL;
> +    const char *s = "my other dummy string";
> +    UserDefOne *ret;
> +    UserDefOne val;
> +
> +    ret = OBJECT_PROPERTY_GET_PTR(OBJECT(dobj), "qv",
> +                                  UserDefOne, &local_err);
> +    g_assert(!local_err);
> +
> +    g_assert_cmpint(ret->integer, ==, 0);
> +    g_assert_cmpstr(ret->string, ==, "dummy string");
> +    g_assert(!ret->has_enum1);
> +    qapi_free_UserDefOne(ret);
> +
> +    val.integer = 42;
> +    val.string = g_strdup(s);
> +    val.has_enum1 = true;
> +    val.enum1 = ENUM_ONE_VALUE1;
> +    OBJECT_PROPERTY_SET_PTR(OBJECT(dobj), &val, "qv",
> +                            UserDefOne, &local_err);
> +    g_assert(!local_err);
> +
> +    ret = OBJECT_PROPERTY_GET_PTR(OBJECT(dobj), "qv",
> +                                  UserDefOne, &local_err);
> +    g_assert(!local_err);
> +
> +    g_assert_cmpint(ret->integer, ==, val.integer);
> +    g_assert_cmpstr(ret->string, ==, val.string);
> +    g_assert(ret->has_enum1);
> +    g_assert_cmpint(ret->enum1, ==, val.enum1);
> +    g_free(val.string);
> +    qapi_free_UserDefOne(ret);
> +}
> +
> +static void test_dummy_get_set_ptr_contravariant(void)
> +{
> +    DummyObject *dobj = DUMMY_OBJECT(object_new(TYPE_DUMMY));
> +    Error *local_err = NULL;
> +    UserDefOneMore *ret;
> +    UserDefOneMore val;
> +
> +    /* You cannot retrieve a contravariant (subclass) type... */
> +    ret = OBJECT_PROPERTY_GET_PTR(OBJECT(dobj), "qv",
> +                                  UserDefOneMore, &local_err);
> +    g_assert(local_err);
> +    g_assert(!ret);
> +    error_free(local_err);
> +    local_err = NULL;
> +
> +    /* And you cannot set one either.  */
> +    val.integer = 42;
> +    val.string = g_strdup("unused");
> +    val.has_enum1 = false;
> +    val.boolean = false;
> +
> +    OBJECT_PROPERTY_SET_PTR(OBJECT(dobj), &val, "qv",
> +                            UserDefOneMore, &local_err);
> +    g_assert(local_err);
> +}
> +
> +static void test_dummy_get_set_ptr_covariant(void)
> +{
> +    DummyObject *dobj = DUMMY_OBJECT(object_new(TYPE_DUMMY));
> +    Error *local_err = NULL;
> +    UserDefZero *ret;
> +    UserDefZero val;
> +
> +    /* You can retrieve a covariant (superclass) type... */
> +    ret = OBJECT_PROPERTY_GET_PTR(OBJECT(dobj), "qv",
> +                                  UserDefZero, &local_err);
> +    g_assert(!local_err);
> +
> +    g_assert_cmpint(ret->integer, ==, 0);
> +    qapi_free_UserDefZero(ret);
> +
> +    /* But you cannot set one.  */
> +    val.integer = 42;
> +    OBJECT_PROPERTY_SET_PTR(OBJECT(dobj), &val, "qv",
> +                            UserDefZero, &local_err);
> +    g_assert(local_err);
> +    error_free(local_err);
> +    local_err = NULL;
> +
> +    /* Test that the property has not been modified at all */
> +    ret = OBJECT_PROPERTY_GET_PTR(OBJECT(dobj), "qv",
> +                                  UserDefZero, &local_err);
> +    g_assert(!local_err);
> +
> +    g_assert_cmpint(ret->integer, ==, 0);
> +    qapi_free_UserDefZero(ret);
> +}
> +
> +static void test_dummy_get_set_ptr_error(void)
> +{
> +    DummyObject *dobj = DUMMY_OBJECT(object_new(TYPE_DUMMY));
> +    Error *local_err = NULL;
> +    const char *s = "my other dummy string";
> +    UserDefOne *ret;
> +    UserDefOne val;
> +
> +    ret = OBJECT_PROPERTY_GET_PTR(OBJECT(dobj), "blah",
> +                                  UserDefOne, &local_err);
> +    g_assert(local_err);
> +    g_assert(!ret);
> +    error_free(local_err);
> +    local_err = NULL;
> +
> +    val.integer = 42;
> +    val.string = g_strdup(s);
> +    val.has_enum1 = true;
> +    val.enum1 = 100;
> +    OBJECT_PROPERTY_SET_PTR(OBJECT(dobj), &val, "qv",
> +                            UserDefOne, &local_err);
> +    g_assert(local_err);
> +    error_free(local_err);
> +    local_err = NULL;
> +
> +    ret = OBJECT_PROPERTY_GET_PTR(OBJECT(dobj), "qv",
> +                                  UserDefOne, &local_err);
> +    g_assert(!local_err);
> +
> +    /* Test that the property has not been modified at all */
> +    g_assert_cmpint(ret->integer, ==, 0);
> +    g_assert_cmpstr(ret->string, ==, "dummy string");
> +    g_assert(!ret->has_enum1);
> +    qapi_free_UserDefOne(ret);
> +}
> +
>  int main(int argc, char **argv)
>  {
>      g_test_init(&argc, &argv, NULL);
> @@ -530,5 +707,9 @@ int main(int argc, char **argv)
>      g_test_add_func("/qom/proplist/iterator", test_dummy_iterator);
>      g_test_add_func("/qom/proplist/delchild", test_dummy_delchild);
>  
> +    g_test_add_func("/qom/proplist/get-set-ptr/struct", 
> test_dummy_get_set_ptr_struct);
> +    g_test_add_func("/qom/proplist/get-set-ptr/error", 
> test_dummy_get_set_ptr_error);
> +    g_test_add_func("/qom/proplist/get-set-ptr/covariant", 
> test_dummy_get_set_ptr_covariant);
> +    g_test_add_func("/qom/proplist/get-set-ptr/contravariant", 
> test_dummy_get_set_ptr_contravariant);
>      return g_test_run();
>  }
> diff --git a/tests/qapi-schema/qapi-schema-test.json 
> b/tests/qapi-schema/qapi-schema-test.json
> index f4d8cc4..4e3f6ff 100644
> --- a/tests/qapi-schema/qapi-schema-test.json
> +++ b/tests/qapi-schema/qapi-schema-test.json
> @@ -91,6 +91,14 @@
>              '*enum1': 'EnumOne' } }   # intentional forward reference
>  
>  ##
> +# @UserDefOneMore:
> +# for testing nested structs
> +##
> +{ 'struct': 'UserDefOneMore',
> +  'base': 'UserDefOne',
> +  'data': { 'boolean': 'bool' } }
> +
> +##
>  # @EnumOne:
>  ##
>  { 'enum': 'EnumOne',
>