qapi: change 'unsigned special_features' to 'uint64_t features'

The "special_features" field / parameter holds the subset of schema
features that are for internal code use. Specifically 'DEPRECATED'
and 'UNSTABLE'.

This special casing of internal features is going to be removed, so
prepare for that by renaming to 'features'. Using a fixed size type
is also best practice for bit fields.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-ID: <20250205123550.2754387-3-berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

include/qapi/compat-policy.h

@@ -18,7 +18,7 @@
 
 extern CompatPolicy compat_policy;
 
-bool compat_policy_input_ok(unsigned special_features,
+bool compat_policy_input_ok(uint64_t features,
                             const CompatPolicy *policy,
                             ErrorClass error_class,
                             const char *kind, const char *name,

include/qapi/qmp-registry.h

@@ -33,7 +33,7 @@ typedef struct QmpCommand
     /* Runs in coroutine context if QCO_COROUTINE is set */
     QmpCommandFunc *fn;
     QmpCommandOptions options;
-    unsigned special_features;
+    uint64_t features;
     QTAILQ_ENTRY(QmpCommand) node;
     bool enabled;
     const char *disable_reason;
@@ -43,7 +43,7 @@ typedef QTAILQ_HEAD(QmpCommandList, QmpCommand) QmpCommandList;
 
 void qmp_register_command(QmpCommandList *cmds, const char *name,
                           QmpCommandFunc *fn, QmpCommandOptions options,
-                          unsigned special_features);
+                          uint64_t features);
 const QmpCommand *qmp_find_command(const QmpCommandList *cmds,
                                    const char *name);
 void qmp_disable_command(QmpCommandList *cmds, const char *name,

include/qapi/util.h

@@ -18,7 +18,7 @@ typedef enum {
 
 typedef struct QEnumLookup {
     const char *const *array;
-    const unsigned char *const special_features;
+    const uint64_t *const features;
     const int size;
 } QEnumLookup;
 

include/qapi/visitor-impl.h

@@ -115,11 +115,11 @@ struct Visitor
 
     /* Optional */
     bool (*policy_reject)(Visitor *v, const char *name,
-                          unsigned special_features, Error **errp);
+                          uint64_t features, Error **errp);
 
     /* Optional */
     bool (*policy_skip)(Visitor *v, const char *name,
-                        unsigned special_features);
+                        uint64_t features);
 
     /* Must be set */
     VisitorType type;

include/qapi/visitor.h

@@ -463,29 +463,29 @@ bool visit_optional(Visitor *v, const char *name, bool *present);
 /*
  * Should we reject member @name due to policy?
  *
- * @special_features is the member's special features encoded as a
- * bitset of QapiSpecialFeature.
+ * @features is the member's special features encoded as a
+ * bitset of QapiFeature.
  *
  * @name must not be NULL.  This function is only useful between
  * visit_start_struct() and visit_end_struct(), since only objects
  * have deprecated members.
  */
 bool visit_policy_reject(Visitor *v, const char *name,
-                         unsigned special_features, Error **errp);
+                         uint64_t features, Error **errp);
 
 /*
  *
  * Should we skip member @name due to policy?
  *
- * @special_features is the member's special features encoded as a
- * bitset of QapiSpecialFeature.
+ * @features is the member's special features encoded as a
+ * bitset of QapiFeature.
  *
  * @name must not be NULL.  This function is only useful between
  * visit_start_struct() and visit_end_struct(), since only objects
  * have deprecated members.
  */
 bool visit_policy_skip(Visitor *v, const char *name,
-                       unsigned special_features);
+                       uint64_t features);
 
 /*
  * Set policy for handling deprecated management interfaces.

qapi/qapi-forward-visitor.c

@@ -246,7 +246,7 @@ static void forward_field_optional(Visitor *v, const char *name, bool *present)
 }
 
 static bool forward_field_policy_reject(Visitor *v, const char *name,
-                                        unsigned special_features,
+                                        uint64_t features,
                                         Error **errp)
 {
     ForwardFieldVisitor *ffv = to_ffv(v);
@@ -254,18 +254,18 @@ static bool forward_field_policy_reject(Visitor *v, const char *name,
     if (!forward_field_translate_name(ffv, &name, errp)) {
         return true;
     }
-    return visit_policy_reject(ffv->target, name, special_features, errp);
+    return visit_policy_reject(ffv->target, name, features, errp);
 }
 
 static bool forward_field_policy_skip(Visitor *v, const char *name,
-                                      unsigned special_features)
+                                      uint64_t features)
 {
     ForwardFieldVisitor *ffv = to_ffv(v);
 
     if (!forward_field_translate_name(ffv, &name, NULL)) {
         return true;
     }
-    return visit_policy_skip(ffv->target, name, special_features);
+    return visit_policy_skip(ffv->target, name, features);
 }
 
 static void forward_field_complete(Visitor *v, void *opaque)

qapi/qapi-util.c

@@ -37,19 +37,19 @@ static bool compat_policy_input_ok1(const char *adjective,
     }
 }
 
-bool compat_policy_input_ok(unsigned special_features,
+bool compat_policy_input_ok(uint64_t features,
                             const CompatPolicy *policy,
                             ErrorClass error_class,
                             const char *kind, const char *name,
                             Error **errp)
 {
-    if ((special_features & 1u << QAPI_DEPRECATED)
+    if ((features & 1u << QAPI_DEPRECATED)
         && !compat_policy_input_ok1("Deprecated",
                                     policy->deprecated_input,
                                     error_class, kind, name, errp)) {
         return false;
     }
-    if ((special_features & (1u << QAPI_UNSTABLE))
+    if ((features & (1u << QAPI_UNSTABLE))
         && !compat_policy_input_ok1("Unstable",
                                     policy->unstable_input,
                                     error_class, kind, name, errp)) {

qapi/qapi-visit-core.c

@@ -141,21 +141,21 @@ bool visit_optional(Visitor *v, const char *name, bool *present)
 }
 
 bool visit_policy_reject(Visitor *v, const char *name,
-                         unsigned special_features, Error **errp)
+                         uint64_t features, Error **errp)
 {
     trace_visit_policy_reject(v, name);
     if (v->policy_reject) {
-        return v->policy_reject(v, name, special_features, errp);
+        return v->policy_reject(v, name, features, errp);
     }
     return false;
 }
 
 bool visit_policy_skip(Visitor *v, const char *name,
-                       unsigned special_features)
+                       uint64_t features)
 {
     trace_visit_policy_skip(v, name);
     if (v->policy_skip) {
-        return v->policy_skip(v, name, special_features);
+        return v->policy_skip(v, name, features);
     }
     return false;
 }
@@ -409,8 +409,8 @@ static bool input_type_enum(Visitor *v, const char *name, int *obj,
         return false;
     }
 
-    if (lookup->special_features
-        && !compat_policy_input_ok(lookup->special_features[value],
+    if (lookup->features
+        && !compat_policy_input_ok(lookup->features[value],
                                    &v->compat_policy,
                                    ERROR_CLASS_GENERIC_ERROR,
                                    "value", enum_str, errp)) {

qapi/qmp-dispatch.c

@@ -173,7 +173,7 @@ QDict *coroutine_mixed_fn qmp_dispatch(const QmpCommandList *cmds, QObject *requ
                   "The command %s has not been found", command);
         goto out;
     }
-    if (!compat_policy_input_ok(cmd->special_features, &compat_policy,
+    if (!compat_policy_input_ok(cmd->features, &compat_policy,
                                 ERROR_CLASS_COMMAND_NOT_FOUND,
                                 "command", command, &err)) {
         goto out;

qapi/qmp-registry.c

@@ -17,7 +17,7 @@
 
 void qmp_register_command(QmpCommandList *cmds, const char *name,
                           QmpCommandFunc *fn, QmpCommandOptions options,
-                          unsigned special_features)
+                          uint64_t features)
 {
     QmpCommand *cmd = g_malloc0(sizeof(*cmd));
 
@@ -28,7 +28,7 @@ void qmp_register_command(QmpCommandList *cmds, const char *name,
     cmd->fn = fn;
     cmd->enabled = true;
     cmd->options = options;
-    cmd->special_features = special_features;
+    cmd->features = features;
     QTAILQ_INSERT_TAIL(cmds, cmd, node);
 }
 

qapi/qobject-input-visitor.c

@@ -664,10 +664,10 @@ static void qobject_input_optional(Visitor *v, const char *name, bool *present)
 }
 
 static bool qobject_input_policy_reject(Visitor *v, const char *name,
-                                        unsigned special_features,
+                                        uint64_t features,
                                         Error **errp)
 {
-    return !compat_policy_input_ok(special_features, &v->compat_policy,
+    return !compat_policy_input_ok(features, &v->compat_policy,
                                    ERROR_CLASS_GENERIC_ERROR,
                                    "parameter", name, errp);
 }

qapi/qobject-output-visitor.c

@@ -210,13 +210,13 @@ static bool qobject_output_type_null(Visitor *v, const char *name,
 }
 
 static bool qobject_output_policy_skip(Visitor *v, const char *name,
-                                       unsigned special_features)
+                                       uint64_t features)
 {
     CompatPolicy *pol = &v->compat_policy;
 
-    return ((special_features & 1u << QAPI_DEPRECATED)
+    return ((features & 1u << QAPI_DEPRECATED)
             && pol->deprecated_output == COMPAT_POLICY_OUTPUT_HIDE)
-        || ((special_features & 1u << QAPI_UNSTABLE)
+        || ((features & 1u << QAPI_UNSTABLE)
             && pol->unstable_output == COMPAT_POLICY_OUTPUT_HIDE);
 }
 

scripts/qapi/types.py

@@ -71,7 +71,7 @@ def gen_enum_lookup(name: str,
     if feats:
         ret += mcgen('''
     },
-    .special_features = (const unsigned char[%(max_index)s]) {
+    .features = (const uint64_t[%(max_index)s]) {
 ''',
                      max_index=max_index)
         ret += feats