qed: Inline qed_commit_l2_update()
[qemu/kevin.git] / qobject / qnum.c
blob476e81c93b37f35c3ac131ba5c5396357826fc7e
1 /*
2 * QNum Module
4 * Copyright (C) 2009 Red Hat Inc.
6 * Authors:
7 * Luiz Capitulino <lcapitulino@redhat.com>
8 * Anthony Liguori <aliguori@us.ibm.com>
9 * Marc-André Lureau <marcandre.lureau@redhat.com>
11 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
12 * See the COPYING.LIB file in the top-level directory.
15 #include "qemu/osdep.h"
16 #include "qapi/error.h"
17 #include "qapi/qmp/qnum.h"
18 #include "qapi/qmp/qobject.h"
19 #include "qemu-common.h"
21 /**
22 * qnum_from_int(): Create a new QNum from an int64_t
24 * Return strong reference.
26 QNum *qnum_from_int(int64_t value)
28 QNum *qn = g_new(QNum, 1);
30 qobject_init(QOBJECT(qn), QTYPE_QNUM);
31 qn->kind = QNUM_I64;
32 qn->u.i64 = value;
34 return qn;
37 /**
38 * qnum_from_uint(): Create a new QNum from an uint64_t
40 * Return strong reference.
42 QNum *qnum_from_uint(uint64_t value)
44 QNum *qn = g_new(QNum, 1);
46 qobject_init(QOBJECT(qn), QTYPE_QNUM);
47 qn->kind = QNUM_U64;
48 qn->u.u64 = value;
50 return qn;
53 /**
54 * qnum_from_double(): Create a new QNum from a double
56 * Return strong reference.
58 QNum *qnum_from_double(double value)
60 QNum *qn = g_new(QNum, 1);
62 qobject_init(QOBJECT(qn), QTYPE_QNUM);
63 qn->kind = QNUM_DOUBLE;
64 qn->u.dbl = value;
66 return qn;
69 /**
70 * qnum_get_try_int(): Get an integer representation of the number
72 * Return true on success.
74 bool qnum_get_try_int(const QNum *qn, int64_t *val)
76 switch (qn->kind) {
77 case QNUM_I64:
78 *val = qn->u.i64;
79 return true;
80 case QNUM_U64:
81 if (qn->u.u64 > INT64_MAX) {
82 return false;
84 *val = qn->u.u64;
85 return true;
86 case QNUM_DOUBLE:
87 return false;
90 assert(0);
91 return false;
94 /**
95 * qnum_get_int(): Get an integer representation of the number
97 * assert() on failure.
99 int64_t qnum_get_int(const QNum *qn)
101 int64_t val;
102 bool success = qnum_get_try_int(qn, &val);
103 assert(success);
104 return val;
108 * qnum_get_uint(): Get an unsigned integer from the number
110 * Return true on success.
112 bool qnum_get_try_uint(const QNum *qn, uint64_t *val)
114 switch (qn->kind) {
115 case QNUM_I64:
116 if (qn->u.i64 < 0) {
117 return false;
119 *val = qn->u.i64;
120 return true;
121 case QNUM_U64:
122 *val = qn->u.u64;
123 return true;
124 case QNUM_DOUBLE:
125 return false;
128 assert(0);
129 return false;
133 * qnum_get_uint(): Get an unsigned integer from the number
135 * assert() on failure.
137 uint64_t qnum_get_uint(const QNum *qn)
139 uint64_t val;
140 bool success = qnum_get_try_uint(qn, &val);
141 assert(success);
142 return val;
146 * qnum_get_double(): Get a float representation of the number
148 * qnum_get_double() loses precision for integers beyond 53 bits.
150 double qnum_get_double(QNum *qn)
152 switch (qn->kind) {
153 case QNUM_I64:
154 return qn->u.i64;
155 case QNUM_U64:
156 return qn->u.u64;
157 case QNUM_DOUBLE:
158 return qn->u.dbl;
161 assert(0);
162 return 0.0;
165 char *qnum_to_string(QNum *qn)
167 char *buffer;
168 int len;
170 switch (qn->kind) {
171 case QNUM_I64:
172 return g_strdup_printf("%" PRId64, qn->u.i64);
173 case QNUM_U64:
174 return g_strdup_printf("%" PRIu64, qn->u.u64);
175 case QNUM_DOUBLE:
176 /* FIXME: snprintf() is locale dependent; but JSON requires
177 * numbers to be formatted as if in the C locale. Dependence
178 * on C locale is a pervasive issue in QEMU. */
179 /* FIXME: This risks printing Inf or NaN, which are not valid
180 * JSON values. */
181 /* FIXME: the default precision of 6 for %f often causes
182 * rounding errors; we should be using DBL_DECIMAL_DIG (17),
183 * and only rounding to a shorter number if the result would
184 * still produce the same floating point value. */
185 buffer = g_strdup_printf("%f" , qn->u.dbl);
186 len = strlen(buffer);
187 while (len > 0 && buffer[len - 1] == '0') {
188 len--;
191 if (len && buffer[len - 1] == '.') {
192 buffer[len - 1] = 0;
193 } else {
194 buffer[len] = 0;
197 return buffer;
200 assert(0);
201 return NULL;
205 * qobject_to_qnum(): Convert a QObject into a QNum
207 QNum *qobject_to_qnum(const QObject *obj)
209 if (!obj || qobject_type(obj) != QTYPE_QNUM) {
210 return NULL;
212 return container_of(obj, QNum, base);
216 * qnum_destroy_obj(): Free all memory allocated by a
217 * QNum object
219 void qnum_destroy_obj(QObject *obj)
221 assert(obj != NULL);
222 g_free(qobject_to_qnum(obj));