qom: Make enum string tables const-correct

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>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>

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;

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

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

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);

include/qom/object.h

@@ -1081,7 +1081,7 @@ 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:

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)
 {

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;

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)
 {

qom/object.c

@@ -1070,7 +1070,7 @@ 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;

scripts/qapi-types.py

@@ -105,7 +105,7 @@ def generate_struct(expr):
 
 def generate_enum_lookup(name, values):
     ret = mcgen('''
-const char *%(name)s_lookup[] = {
+const char * const %(name)s_lookup[] = {
 ''',
                 name=c_name(name))
     i = 0
@@ -128,7 +128,7 @@ def generate_enum_lookup(name, values):
 def generate_enum(name, values):
     name = c_name(name)
     lookup_decl = mcgen('''
-extern const char *%(name)s_lookup[];
+extern const char * const %(name)s_lookup[];
 ''',
                 name=name)