Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 1 | /* |
| 2 | * QNum Module |
| 3 | * |
| 4 | * Copyright (C) 2009 Red Hat Inc. |
| 5 | * |
| 6 | * Authors: |
| 7 | * Luiz Capitulino <lcapitulino@redhat.com> |
| 8 | * Anthony Liguori <aliguori@us.ibm.com> |
| 9 | * Marc-André Lureau <marcandre.lureau@redhat.com> |
| 10 | * |
| 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. |
| 13 | */ |
| 14 | |
| 15 | #include "qemu/osdep.h" |
Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 16 | #include "qapi/qmp/qnum.h" |
Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 17 | |
| 18 | /** |
| 19 | * qnum_from_int(): Create a new QNum from an int64_t |
| 20 | * |
| 21 | * Return strong reference. |
| 22 | */ |
| 23 | QNum *qnum_from_int(int64_t value) |
| 24 | { |
| 25 | QNum *qn = g_new(QNum, 1); |
| 26 | |
| 27 | qobject_init(QOBJECT(qn), QTYPE_QNUM); |
| 28 | qn->kind = QNUM_I64; |
| 29 | qn->u.i64 = value; |
| 30 | |
| 31 | return qn; |
| 32 | } |
| 33 | |
| 34 | /** |
Marc-André Lureau | 61a8f41 | 2017-06-07 20:36:01 +0400 | [diff] [blame] | 35 | * qnum_from_uint(): Create a new QNum from an uint64_t |
| 36 | * |
| 37 | * Return strong reference. |
| 38 | */ |
| 39 | QNum *qnum_from_uint(uint64_t value) |
| 40 | { |
| 41 | QNum *qn = g_new(QNum, 1); |
| 42 | |
| 43 | qobject_init(QOBJECT(qn), QTYPE_QNUM); |
| 44 | qn->kind = QNUM_U64; |
| 45 | qn->u.u64 = value; |
| 46 | |
| 47 | return qn; |
| 48 | } |
| 49 | |
| 50 | /** |
Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 51 | * qnum_from_double(): Create a new QNum from a double |
| 52 | * |
| 53 | * Return strong reference. |
| 54 | */ |
| 55 | QNum *qnum_from_double(double value) |
| 56 | { |
| 57 | QNum *qn = g_new(QNum, 1); |
| 58 | |
| 59 | qobject_init(QOBJECT(qn), QTYPE_QNUM); |
| 60 | qn->kind = QNUM_DOUBLE; |
| 61 | qn->u.dbl = value; |
| 62 | |
| 63 | return qn; |
| 64 | } |
| 65 | |
| 66 | /** |
| 67 | * qnum_get_try_int(): Get an integer representation of the number |
| 68 | * |
| 69 | * Return true on success. |
| 70 | */ |
| 71 | bool qnum_get_try_int(const QNum *qn, int64_t *val) |
| 72 | { |
| 73 | switch (qn->kind) { |
| 74 | case QNUM_I64: |
| 75 | *val = qn->u.i64; |
| 76 | return true; |
Marc-André Lureau | 61a8f41 | 2017-06-07 20:36:01 +0400 | [diff] [blame] | 77 | case QNUM_U64: |
| 78 | if (qn->u.u64 > INT64_MAX) { |
| 79 | return false; |
| 80 | } |
| 81 | *val = qn->u.u64; |
| 82 | return true; |
Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 83 | case QNUM_DOUBLE: |
| 84 | return false; |
| 85 | } |
| 86 | |
| 87 | assert(0); |
| 88 | return false; |
| 89 | } |
| 90 | |
| 91 | /** |
| 92 | * qnum_get_int(): Get an integer representation of the number |
| 93 | * |
| 94 | * assert() on failure. |
| 95 | */ |
| 96 | int64_t qnum_get_int(const QNum *qn) |
| 97 | { |
| 98 | int64_t val; |
| 99 | bool success = qnum_get_try_int(qn, &val); |
| 100 | assert(success); |
| 101 | return val; |
| 102 | } |
| 103 | |
| 104 | /** |
Marc-André Lureau | 61a8f41 | 2017-06-07 20:36:01 +0400 | [diff] [blame] | 105 | * qnum_get_uint(): Get an unsigned integer from the number |
| 106 | * |
| 107 | * Return true on success. |
| 108 | */ |
| 109 | bool qnum_get_try_uint(const QNum *qn, uint64_t *val) |
| 110 | { |
| 111 | switch (qn->kind) { |
| 112 | case QNUM_I64: |
| 113 | if (qn->u.i64 < 0) { |
| 114 | return false; |
| 115 | } |
| 116 | *val = qn->u.i64; |
| 117 | return true; |
| 118 | case QNUM_U64: |
| 119 | *val = qn->u.u64; |
| 120 | return true; |
| 121 | case QNUM_DOUBLE: |
| 122 | return false; |
| 123 | } |
| 124 | |
| 125 | assert(0); |
| 126 | return false; |
| 127 | } |
| 128 | |
| 129 | /** |
| 130 | * qnum_get_uint(): Get an unsigned integer from the number |
| 131 | * |
| 132 | * assert() on failure. |
| 133 | */ |
| 134 | uint64_t qnum_get_uint(const QNum *qn) |
| 135 | { |
| 136 | uint64_t val; |
| 137 | bool success = qnum_get_try_uint(qn, &val); |
| 138 | assert(success); |
| 139 | return val; |
| 140 | } |
| 141 | |
| 142 | /** |
Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 143 | * qnum_get_double(): Get a float representation of the number |
| 144 | * |
| 145 | * qnum_get_double() loses precision for integers beyond 53 bits. |
| 146 | */ |
| 147 | double qnum_get_double(QNum *qn) |
| 148 | { |
| 149 | switch (qn->kind) { |
| 150 | case QNUM_I64: |
| 151 | return qn->u.i64; |
Marc-André Lureau | 61a8f41 | 2017-06-07 20:36:01 +0400 | [diff] [blame] | 152 | case QNUM_U64: |
| 153 | return qn->u.u64; |
Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 154 | case QNUM_DOUBLE: |
| 155 | return qn->u.dbl; |
| 156 | } |
| 157 | |
| 158 | assert(0); |
| 159 | return 0.0; |
| 160 | } |
| 161 | |
| 162 | char *qnum_to_string(QNum *qn) |
| 163 | { |
| 164 | char *buffer; |
| 165 | int len; |
| 166 | |
| 167 | switch (qn->kind) { |
| 168 | case QNUM_I64: |
| 169 | return g_strdup_printf("%" PRId64, qn->u.i64); |
Marc-André Lureau | 61a8f41 | 2017-06-07 20:36:01 +0400 | [diff] [blame] | 170 | case QNUM_U64: |
| 171 | return g_strdup_printf("%" PRIu64, qn->u.u64); |
Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 172 | case QNUM_DOUBLE: |
| 173 | /* FIXME: snprintf() is locale dependent; but JSON requires |
| 174 | * numbers to be formatted as if in the C locale. Dependence |
| 175 | * on C locale is a pervasive issue in QEMU. */ |
| 176 | /* FIXME: This risks printing Inf or NaN, which are not valid |
| 177 | * JSON values. */ |
| 178 | /* FIXME: the default precision of 6 for %f often causes |
| 179 | * rounding errors; we should be using DBL_DECIMAL_DIG (17), |
| 180 | * and only rounding to a shorter number if the result would |
| 181 | * still produce the same floating point value. */ |
| 182 | buffer = g_strdup_printf("%f" , qn->u.dbl); |
| 183 | len = strlen(buffer); |
| 184 | while (len > 0 && buffer[len - 1] == '0') { |
| 185 | len--; |
| 186 | } |
| 187 | |
| 188 | if (len && buffer[len - 1] == '.') { |
| 189 | buffer[len - 1] = 0; |
| 190 | } else { |
| 191 | buffer[len] = 0; |
| 192 | } |
| 193 | |
| 194 | return buffer; |
| 195 | } |
| 196 | |
| 197 | assert(0); |
| 198 | return NULL; |
| 199 | } |
| 200 | |
| 201 | /** |
Max Reitz | b38dd67 | 2017-11-14 19:01:25 +0100 | [diff] [blame] | 202 | * qnum_is_equal(): Test whether the two QNums are equal |
| 203 | * |
| 204 | * Negative integers are never considered equal to unsigned integers, |
| 205 | * but positive integers in the range [0, INT64_MAX] are considered |
| 206 | * equal independently of whether the QNum's kind is i64 or u64. |
| 207 | * |
| 208 | * Doubles are never considered equal to integers. |
| 209 | */ |
| 210 | bool qnum_is_equal(const QObject *x, const QObject *y) |
| 211 | { |
Max Reitz | 7dc847e | 2018-02-24 16:40:29 +0100 | [diff] [blame] | 212 | QNum *num_x = qobject_to(QNum, x); |
| 213 | QNum *num_y = qobject_to(QNum, y); |
Max Reitz | b38dd67 | 2017-11-14 19:01:25 +0100 | [diff] [blame] | 214 | |
| 215 | switch (num_x->kind) { |
| 216 | case QNUM_I64: |
| 217 | switch (num_y->kind) { |
| 218 | case QNUM_I64: |
| 219 | /* Comparison in native int64_t type */ |
| 220 | return num_x->u.i64 == num_y->u.i64; |
| 221 | case QNUM_U64: |
| 222 | /* Implicit conversion of x to uin64_t, so we have to |
| 223 | * check its sign before */ |
| 224 | return num_x->u.i64 >= 0 && num_x->u.i64 == num_y->u.u64; |
| 225 | case QNUM_DOUBLE: |
| 226 | return false; |
| 227 | } |
| 228 | abort(); |
| 229 | case QNUM_U64: |
| 230 | switch (num_y->kind) { |
| 231 | case QNUM_I64: |
| 232 | return qnum_is_equal(y, x); |
| 233 | case QNUM_U64: |
| 234 | /* Comparison in native uint64_t type */ |
| 235 | return num_x->u.u64 == num_y->u.u64; |
| 236 | case QNUM_DOUBLE: |
| 237 | return false; |
| 238 | } |
| 239 | abort(); |
| 240 | case QNUM_DOUBLE: |
| 241 | switch (num_y->kind) { |
| 242 | case QNUM_I64: |
| 243 | case QNUM_U64: |
| 244 | return false; |
| 245 | case QNUM_DOUBLE: |
| 246 | /* Comparison in native double type */ |
| 247 | return num_x->u.dbl == num_y->u.dbl; |
| 248 | } |
| 249 | abort(); |
| 250 | } |
| 251 | |
| 252 | abort(); |
| 253 | } |
| 254 | |
| 255 | /** |
Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 256 | * qnum_destroy_obj(): Free all memory allocated by a |
| 257 | * QNum object |
| 258 | */ |
| 259 | void qnum_destroy_obj(QObject *obj) |
| 260 | { |
| 261 | assert(obj != NULL); |
Max Reitz | 7dc847e | 2018-02-24 16:40:29 +0100 | [diff] [blame] | 262 | g_free(qobject_to(QNum, obj)); |
Marc-André Lureau | 01b2ffc | 2017-06-07 20:35:58 +0400 | [diff] [blame] | 263 | } |