A QOM property can be parsed as enum using the visit_type_enum()
helper function, 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_obj;
      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->devtype = 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: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

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: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

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.

First a pair of functions object_set_props() / object_set_propv()
are added which allow for a list of objects to be set in
one single API call.

Then object_new_with_props() / object_new_with_propv() constructors
are added which simplify the sequence of calls to create an
object, populate properties, register in the object composition
tree and mark the object complete, into a single method call.

Usage would be:

   Error *err = NULL;
   Object *obj;
   obj = object_new_with_propv(TYPE_MEMORY_BACKEND_FILE,
                               object_get_objects_root(),
                               "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, using normal QOM
semantics for parsing from string format.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Add object_get_objects_root() function which is a convenience for
obtaining the Object * located at /objects in the object
composition tree. Convert existing code over to use the new
API where appropriate.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

With this, object_property_add_alias() callers can safely free the
target property name, like what already happens with the 'name' argument
to all object_property_add*() functions.
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Suggested-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Commit 80742642 (qom: Add description field in ObjectProperty struct)
introduced property descriptions and copied them for alias properties.

Instead of using the caller-supplied property name, use the returned
property name for setting the description. This avoids an Error when
setting a property description for a property with literal "[*]" that
doesn't exist due to automatic property naming in object_property_add().
Reviewed-by: NGonglei <arei.gonglei@huawei.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: qemu-stable@nongnu.org (v2.2+)
Signed-off-by: NAndreas Färber <afaerber@suse.de>

The mc146818rtc driver exposes the current RTC date and time via the "date"
property in QOM (which is also aliased to the machine's "rtc-time"
property).  Currently it uses a custom visitor function rtc_get_date to
do this.

This patch introduces new helpers to the QOM core to expose struct tm
valued properties via a getter function, so that this functionality can be
more easily duplicated in other RTC implementations.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Rather than an abort(). This allows callers to decide whether parenting
an already-parented object is a fatal error condition.

Useful for providing a default value for an object's parent in the case
where you want to set one iff it doesn't already have one.
Reviewed-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

By passing in "" to object_property_set_link.

The lead user of this is the QDEV GPIO framework which will implement
GPIO disconnects via an "unlink".  GPIO disconnection is used by
qtest's irq_intercept_out command.
Reviewed-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The descriptions can serve as documentation in the code,
and they can be used to provide better help.

Copy property descriptions when copying alias properties.

Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

object_property_add_alias() is called at some
places at present. And its parameter errp may not NULL,
such as
 object_property_add_alias(obj, "iothread", OBJECT(&dev->vdev),"iothread",
                              &error_abort);
This patch add error handler for security.

Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Avoid the caller of object_property_print() leaking string
argument's memory, such as qdev_print_props() when
encounter errors.
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

If "[*]" is given as the last part of a QOM property name, treat that
as an array property. The added property is given the first available
name, replacing the * with a decimal number counting from 0.

First add with name "foo[*]" will be "foo[0]". Second "foo[1]" and so
on.

Callers may inspect the ObjectProperty * return value to see what
number the added property was given.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Current object_child_foreach() uses QTAILQ_FOREACH() to walk
through children and that makes children removal from the callback
impossible.

This makes object_child_foreach() use QTAILQ_FOREACH_SAFE().
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: NHu Tao <hutao@cn.fujitsu.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

string_output_get_string() uses g_string_free(str, false) to
transfer the 'str' pointer to callers and never free it.
Signed-off-by: NChen Fan <chen.fan.fnst@cn.fujitsu.com>
Reviewed-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: NHu Tao <hutao@cn.fujitsu.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

This ensures that the unparent callback is called automatically
when the parent object is finalized.

Note that there's no need to keep a reference neither in
object_unparent nor in object_finalize_child_property.  The
reference held by the child property itself will do.
Reviewed-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This ensures that the children's unparent callback will still
have a usable parent.
Reviewed-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Just do nothing if passed NULL for a ref or unref. This avoids
call sites that manage a combination of NULL or non-NULL pointers
having to add iffery around every ref and unref.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Certain parts of the QOM framework test this pointer to determine if
an object is parented. Nuke it when the object is unparented to allow
for reuse of an object after unparenting.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Child properties must be unique.  Fix this problem by
turning their aliases into links.

The resolve function that forwards to the target property
does not have any knowledge of the target property's type,
so it works fine.
Reviewed-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

It may be desirable to have custom link<> properties that do more
than just store an object.  Even the addition of a "check"
function is not enough if setting the link has side effects
or if a non-standard reference counting is preferrable.

Avoid the assumption that the opaque field of a link<> is a
LinkProperty struct, by adding a generic "resolve" callback
to ObjectProperty.  This fixes aliases of link properties.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Sometimes an object needs to present a property which is actually on
another object, or it needs to provide an alias name for an existing
property.

Examples:
  a.foo -> b.foo
  a.old_name -> a.new_name

The new object_property_add_alias() API allows objects to alias a
property on the same object or another object.  The source and target
names can be different.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>

Certain parts of the QOM framework test this pointer to determine if
an object is parented. Nuke it when the object is unparented to allow
for reuse of an object after unparenting.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Signed-off-by: NHu Tao <hutao@cn.fujitsu.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Just hardcode them in the callers

Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

Commit 9561fda8 changed the type of
'opaque' for link properties, but missed updating this call site.
Reproducer:

./x86_64-softmmu/qemu-system-x86_64 -qmp unix:./qmp.sock,server &
./scripts/qmp/qmp-shell ./qmp.sock
(QEMU) qom-list path=//machine/i440fx/pci.0/child[2]
Reported-by: NMarcin Gibuła <m.gibula@beyond.pl>
Signed-off-by: NCole Robinson <crobinso@redhat.com>
Message-id: 2f8f007ce2152ac3b65f0811199662799c509225.1397155389.git.crobinso@redhat.com
Acked-by: NAndreas Färber <afaerber@suse.de>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

There are currently three types of object_property_add_link() callers:

1. The link property may be set at any time.
2. The link property of a DeviceState instance may only be set before
   realize.
3. The link property may never be set, it is read-only.

Something similar can already be achieved with
object_property_add_str()'s set() argument.  Follow its example and add
a check() argument to object_property_add_link().

Also provide default check() functions for case #1 and #2.  Case #3 is
covered by passing a NULL function pointer.

Cc: Peter Crosthwaite <peter.crosthwaite@petalogix.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Anthony Liguori <aliguori@amazon.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
[AF: Tweaked documentation comment]
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Some object_property_add_link() callers expect property deletion to
unref the link property object.  Other callers expect to manage the
refcount themselves.  The former are currently broken and therefore leak
the link property object.

This patch adds a flags argument to object_property_add_link() so the
caller can specify which refcount behavior they require.  The new
OBJ_PROP_LINK_UNREF_ON_RELEASE flag causes the link pointer to be
unreferenced when the property is deleted.

This fixes refcount leaks in qdev.c, xilinx_axidma.c, xilinx_axienet.c,
s390-virtio-bus.c, virtio-pci.c, virtio-rng.c, and ui/console.c.

Rationale for refcount behavior:

 * hw/core/qdev.c
   - bus children are explicitly unreferenced, don't interfere
   - parent_bus is essentially a read-only property that doesn't hold a
     refcount, don't unref
   - hotplug_handler is leaked, do unref

 * hw/dma/xilinx_axidma.c
   - rx stream "dma" links are set using set_link, therefore they
     need unref
   - tx streams are set using set_link, therefore they need unref

 * hw/net/xilinx_axienet.c
   - same reasoning as hw/dma/xilinx_axidma.c

 * hw/pcmcia/pxa2xx.c
   - pxa2xx bypasses set_link and therefore does not use refcounts

 * hw/s390x/s390-virtio-bus.c
 * hw/virtio/virtio-pci.c
 * hw/virtio/virtio-rng.c
 * ui/console.c
   - set_link is used and there is no explicit unref, do unref

Cc: Peter Crosthwaite <peter.crosthwaite@petalogix.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Anthony Liguori <aliguori@amazon.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

The error behavior of object_property_set_link() is dangerous.  It sets
the link property object to NULL if an error occurs.  A setter function
should either succeed or fail, it shouldn't leave the value NULL on
failure.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

The path resolution logic in object_property_set_link() should be a
separate function.  This makes the code easier to read and maintain.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

It is often useful to find an object's child property name.  Also use
this new function to simplify the implementation of
object_get_canonical_path().
Reviewed-by: NAndreas Färber <afaerber@suse.de>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

When object_property_add_str() and object_property_add_bool() fail, they
leak their internal StringProperty and BoolProperty structs.  Remember
to free the structs on error.

Luckily this is a low-impact memory leak since most QOM properties are
static qdev properties that will never take the error case.
object_property_add() only fails if the property name is already in use.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: NAndreas Färber <afaerber@suse.de>

This will be used by "info qtree".  For numbers it prints both the
decimal and hex values.  For sizes it rounds to the nearest power
of 2^10.  For strings, it puts quotes around the string and separates
NULL and empty string.
Reviewed-by: NIgor Mammedov <imammedo@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NIgor Mammedov <imammedo@redhat.com>
Tested-by: NIgor Mammedov <imammedo@redhat.com>
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

We should not modify the type hash table while it is being iterated on.
Assert that it does not happen.
Signed-off-by: NHervé Poussineau <hpoussin@reactos.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

There should be no need to look up nor enumerate the interface "types",
whose "classes" are really just vtables.  Just create the types and
add them to the interface list of the parent type.

Interfaces not registering their type anymore means that accessing
superclass::interface by type name will fail when initializing
subclass::interface.  Thus, we need to pre-initialize the subclass's
parent_type field before calling type_initialize.  Apart from this, the
interface "types" should never be used and thus it is harmless to leave
them out of the hashtable.

Further, the interface types had a bug with interfaces that are
inherited from a superclass:  The implementation type name was wrong
(for example it was subclass::superclass::interface rather than
just subclass::interface).  This patch fixes this as well.
Reported-by: NIgor Mammedov <imammedo@redhat.com>
Tested-by: NIgor Mammedov <imammedo@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

The object-cast and class-cast caches cannot be shared because class
caching is conditional on the target type not being an interface and
object caching is unconditional. Leads to a bug when a class cast
to an interface follows an object cast to the same interface type:

FooObject = FOO(obj);
FooClass = FOO_GET_CLASS(obj);

Where TYPE_FOO is an interface. The first (object) cast will be
successful and cache the casting result (i.e. TYPE_FOO will be cached).
The second (class) cast will then check the shared cast cache
and register a hit. The issue is, when a class cast hits in the cache
it just returns a pointer cast of the input class (i.e. the concrete
class).

When casting to an interface, the cast itself must return the
interface class, not the concrete class. The implementation of class
cast caching already ensures that the returned cast result is only
a pointer cast before caching. The object cast logic however does
not have this check.

Resolve by just splitting the object and class caches.

Cc: qemu-stable@nongnu.org
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Tested-by: NNathan Rossi <nathan.rossi@xilinx.com>
Reviewed-by: NEdgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Save the result of the call to object_get_canonical_path()
so we can free it.

Cc: qemu-stable@nongnu.org
Signed-off-by: NVlad Yasevich <vyasevic@redhat.com>
Reviewed-by: NAmos Kong <akong@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Make it easy to add read-only helpers for simple
integer properties in memory.
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NGerd Hoffmann <kraxel@redhat.com>
Tested-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NIgor Mammedov <imammedo@redhat.com>
Tested-by: NIgor Mammedov <imammedo@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>