The discriminator for anonymous unions is the data type. This allows to
have a union type that allows both of these:
    { 'file': 'my_existing_block_device_id' }
    { 'file': { 'filename': '/tmp/mydisk.qcow2', 'read-only': true } }
Unions like this are specified in the schema with an empty dict as
discriminator. For this example you could take:
    { 'union': 'BlockRef',
      'discriminator': {},
      'data': { 'definition': 'BlockOptions',
                'reference': 'str' } }
    { 'type': 'ExampleObject',
      'data: { 'file': 'BlockRef' } }
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
		
	
			
		
			
				
	
	
		
			70 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
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			70 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Core Definitions for QAPI Visitor implementations
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 *
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 * Copyright (C) 2012 Red Hat, Inc.
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 *
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 * Author: Paolo Bonizni <pbonzini@redhat.com>
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 *
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 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
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 * See the COPYING.LIB file in the top-level directory.
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 *
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 */
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#ifndef QAPI_VISITOR_IMPL_H
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#define QAPI_VISITOR_IMPL_H
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#include "qapi/error.h"
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#include "qapi/visitor.h"
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struct Visitor
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{
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    /* Must be set */
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    void (*start_struct)(Visitor *v, void **obj, const char *kind,
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                         const char *name, size_t size, Error **errp);
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    void (*end_struct)(Visitor *v, Error **errp);
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    void (*start_implicit_struct)(Visitor *v, void **obj, size_t size,
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                                  Error **errp);
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    void (*end_implicit_struct)(Visitor *v, Error **errp);
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    void (*start_list)(Visitor *v, const char *name, Error **errp);
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    GenericList *(*next_list)(Visitor *v, GenericList **list, Error **errp);
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    void (*end_list)(Visitor *v, Error **errp);
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    void (*type_enum)(Visitor *v, int *obj, const char *strings[],
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                      const char *kind, const char *name, Error **errp);
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    void (*get_next_type)(Visitor *v, int *kind, const int *qobjects,
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                          const char *name, Error **errp);
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    void (*type_int)(Visitor *v, int64_t *obj, const char *name, Error **errp);
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    void (*type_bool)(Visitor *v, bool *obj, const char *name, Error **errp);
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    void (*type_str)(Visitor *v, char **obj, const char *name, Error **errp);
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    void (*type_number)(Visitor *v, double *obj, const char *name,
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                        Error **errp);
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    /* May be NULL */
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    void (*start_optional)(Visitor *v, bool *present, const char *name,
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                           Error **errp);
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    void (*end_optional)(Visitor *v, Error **errp);
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    void (*start_handle)(Visitor *v, void **obj, const char *kind,
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                         const char *name, Error **errp);
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    void (*end_handle)(Visitor *v, Error **errp);
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    void (*type_uint8)(Visitor *v, uint8_t *obj, const char *name, Error **errp);
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    void (*type_uint16)(Visitor *v, uint16_t *obj, const char *name, Error **errp);
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    void (*type_uint32)(Visitor *v, uint32_t *obj, const char *name, Error **errp);
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    void (*type_uint64)(Visitor *v, uint64_t *obj, const char *name, Error **errp);
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    void (*type_int8)(Visitor *v, int8_t *obj, const char *name, Error **errp);
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    void (*type_int16)(Visitor *v, int16_t *obj, const char *name, Error **errp);
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    void (*type_int32)(Visitor *v, int32_t *obj, const char *name, Error **errp);
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    void (*type_int64)(Visitor *v, int64_t *obj, const char *name, Error **errp);
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    /* visit_type_size() falls back to (*type_uint64)() if type_size is unset */
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    void (*type_size)(Visitor *v, uint64_t *obj, const char *name, Error **errp);
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};
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void input_type_enum(Visitor *v, int *obj, const char *strings[],
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                     const char *kind, const char *name, Error **errp);
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void output_type_enum(Visitor *v, int *obj, const char *strings[],
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                      const char *kind, const char *name, Error **errp);
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#endif
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