RFC 8259 (December 2017) obsoletes RFC 7159 (March 2014). Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180823164025.12553-59-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
		
			
				
	
	
		
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			75 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * QNum Module
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|  *
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|  * Copyright (C) 2009 Red Hat Inc.
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|  *
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|  * Authors:
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|  *  Luiz Capitulino <lcapitulino@redhat.com>
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|  *  Anthony Liguori <aliguori@us.ibm.com>
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|  *  Marc-André Lureau <marcandre.lureau@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 QNUM_H
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| #define QNUM_H
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| 
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| #include "qapi/qmp/qobject.h"
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| 
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| typedef enum {
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|     QNUM_I64,
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|     QNUM_U64,
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|     QNUM_DOUBLE
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| } QNumKind;
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| 
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| /*
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|  * QNum encapsulates how our dialect of JSON fills in the blanks left
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|  * by the JSON specification (RFC 8259) regarding numbers.
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|  *
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|  * Conceptually, we treat number as an abstract type with three
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|  * concrete subtypes: floating-point, signed integer, unsigned
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|  * integer.  QNum implements this as a discriminated union of double,
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|  * int64_t, uint64_t.
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|  *
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|  * The JSON parser picks the subtype as follows.  If the number has a
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|  * decimal point or an exponent, it is floating-point.  Else if it
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|  * fits into int64_t, it's signed integer.  Else if it fits into
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|  * uint64_t, it's unsigned integer.  Else it's floating-point.
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|  *
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|  * Any number can serve as double: qnum_get_double() converts under
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|  * the hood.
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|  *
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|  * An integer can serve as signed / unsigned integer as long as it is
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|  * in range: qnum_get_try_int() / qnum_get_try_uint() check range and
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|  * convert under the hood.
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|  */
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| struct QNum {
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|     struct QObjectBase_ base;
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|     QNumKind kind;
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|     union {
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|         int64_t i64;
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|         uint64_t u64;
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|         double dbl;
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|     } u;
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| };
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| 
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| QNum *qnum_from_int(int64_t value);
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| QNum *qnum_from_uint(uint64_t value);
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| QNum *qnum_from_double(double value);
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| 
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| bool qnum_get_try_int(const QNum *qn, int64_t *val);
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| int64_t qnum_get_int(const QNum *qn);
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| 
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| bool qnum_get_try_uint(const QNum *qn, uint64_t *val);
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| uint64_t qnum_get_uint(const QNum *qn);
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| 
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| double qnum_get_double(QNum *qn);
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| 
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| char *qnum_to_string(QNum *qn);
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| 
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| bool qnum_is_equal(const QObject *x, const QObject *y);
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| void qnum_destroy_obj(QObject *obj);
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| 
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| #endif /* QNUM_H */
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