qapi: Convert QType into QAPI built-in enum type

What's more meta than using qapi to define qapi? :)

Convert QType into a full-fledged[*] builtin qapi enum type, so
that a subsequent patch can then use it as the discriminator
type of qapi alternate types.  Fortunately, the judicious use of
'prefix' in the qapi definition avoids churn to the spelling of
the enum constants.

To avoid circular definitions, we have to flip the order of
inclusion between "qobject.h" vs. "qapi-types.h".  Back in commit
28770e0, we had the latter include the former, so that we could
use 'QObject *' for our implementation of 'any'.  But that usage
also works with only a forward declaration, whereas the
definition of QObject requires QType to be a complete type.

[*] The type has to be builtin, rather than declared in
qapi/common.json, because we want to use it for alternates even
when common.json is not included. But since it is the first
builtin enum type, we have to add special cases to qapi-types
and qapi-visit to only emit definitions once, even when two
qapi files are being compiled into the same binary (the way we
already handled builtin list types like 'intList').  We may
need to revisit how multiple qapi files share common types,
but that's a project for another day.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-4-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

1 files changed, 5 insertions, 16 deletions

diff --git a/include/qapi/qmp/qobject.h b/include/qapi/qmp/qobject.h
index c0f1e99bca..74459ae14b 100644
--- a/include/qapi/qmp/qobject.h
+++ b/include/qapi/qmp/qobject.h
@@ -34,23 +34,12 @@
 
 #include <stddef.h>
 #include <assert.h>
+#include "qapi-types.h"
 
-typedef enum {
-    QTYPE_NONE,    /* sentinel value, no QObject has this type code */
-    QTYPE_QNULL,
-    QTYPE_QINT,
-    QTYPE_QSTRING,
-    QTYPE_QDICT,
-    QTYPE_QLIST,
-    QTYPE_QFLOAT,
-    QTYPE_QBOOL,
-    QTYPE_MAX,
-} QType;
-
-typedef struct QObject {
+struct QObject {
     QType type;
     size_t refcnt;
-} QObject;
+};
 
 /* Get the 'base' part of an object */
 #define QOBJECT(obj) (&(obj)->base)
@@ -66,7 +55,7 @@ typedef struct QObject {
 /* Initialize an object to default values */
 static inline void qobject_init(QObject *obj, QType type)
 {
-    assert(QTYPE_NONE < type && type < QTYPE_MAX);
+    assert(QTYPE_NONE < type && type < QTYPE__MAX);
     obj->refcnt = 1;
     obj->type = type;
 }
@@ -102,7 +91,7 @@ static inline void qobject_decref(QObject *obj)
  */
 static inline QType qobject_type(const QObject *obj)
 {
-    assert(QTYPE_NONE < obj->type && obj->type < QTYPE_MAX);
+    assert(QTYPE_NONE < obj->type && obj->type < QTYPE__MAX);
     return obj->type;
 }