Joey Armstrong | e8c091f | 2023-01-17 16:56:26 -0500 | [diff] [blame] | 1 | // Copyright The OpenTelemetry Authors |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | package metric |
| 16 | |
| 17 | //go:generate stringer -type=NumberKind |
| 18 | |
| 19 | import ( |
| 20 | "fmt" |
| 21 | "math" |
| 22 | "sync/atomic" |
| 23 | |
| 24 | "go.opentelemetry.io/otel/internal" |
| 25 | ) |
| 26 | |
| 27 | // NumberKind describes the data type of the Number. |
| 28 | type NumberKind int8 |
| 29 | |
| 30 | const ( |
| 31 | // Int64NumberKind means that the Number stores int64. |
| 32 | Int64NumberKind NumberKind = iota |
| 33 | // Float64NumberKind means that the Number stores float64. |
| 34 | Float64NumberKind |
| 35 | ) |
| 36 | |
| 37 | // Zero returns a zero value for a given NumberKind |
| 38 | func (k NumberKind) Zero() Number { |
| 39 | switch k { |
| 40 | case Int64NumberKind: |
| 41 | return NewInt64Number(0) |
| 42 | case Float64NumberKind: |
| 43 | return NewFloat64Number(0.) |
| 44 | default: |
| 45 | return Number(0) |
| 46 | } |
| 47 | } |
| 48 | |
| 49 | // Minimum returns the minimum representable value |
| 50 | // for a given NumberKind |
| 51 | func (k NumberKind) Minimum() Number { |
| 52 | switch k { |
| 53 | case Int64NumberKind: |
| 54 | return NewInt64Number(math.MinInt64) |
| 55 | case Float64NumberKind: |
| 56 | return NewFloat64Number(-1. * math.MaxFloat64) |
| 57 | default: |
| 58 | return Number(0) |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | // Maximum returns the maximum representable value |
| 63 | // for a given NumberKind |
| 64 | func (k NumberKind) Maximum() Number { |
| 65 | switch k { |
| 66 | case Int64NumberKind: |
| 67 | return NewInt64Number(math.MaxInt64) |
| 68 | case Float64NumberKind: |
| 69 | return NewFloat64Number(math.MaxFloat64) |
| 70 | default: |
| 71 | return Number(0) |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | // Number represents either an integral or a floating point value. It |
| 76 | // needs to be accompanied with a source of NumberKind that describes |
| 77 | // the actual type of the value stored within Number. |
| 78 | type Number uint64 |
| 79 | |
| 80 | // - constructors |
| 81 | |
| 82 | // NewNumberFromRaw creates a new Number from a raw value. |
| 83 | func NewNumberFromRaw(r uint64) Number { |
| 84 | return Number(r) |
| 85 | } |
| 86 | |
| 87 | // NewInt64Number creates an integral Number. |
| 88 | func NewInt64Number(i int64) Number { |
| 89 | return NewNumberFromRaw(internal.Int64ToRaw(i)) |
| 90 | } |
| 91 | |
| 92 | // NewFloat64Number creates a floating point Number. |
| 93 | func NewFloat64Number(f float64) Number { |
| 94 | return NewNumberFromRaw(internal.Float64ToRaw(f)) |
| 95 | } |
| 96 | |
| 97 | // NewNumberSignChange returns a number with the same magnitude and |
| 98 | // the opposite sign. `kind` must describe the kind of number in `nn`. |
| 99 | // |
| 100 | // Does not change Uint64NumberKind values. |
| 101 | func NewNumberSignChange(kind NumberKind, nn Number) Number { |
| 102 | switch kind { |
| 103 | case Int64NumberKind: |
| 104 | return NewInt64Number(-nn.AsInt64()) |
| 105 | case Float64NumberKind: |
| 106 | return NewFloat64Number(-nn.AsFloat64()) |
| 107 | } |
| 108 | return nn |
| 109 | } |
| 110 | |
| 111 | // - as x |
| 112 | |
| 113 | // AsNumber gets the Number. |
| 114 | func (n *Number) AsNumber() Number { |
| 115 | return *n |
| 116 | } |
| 117 | |
| 118 | // AsRaw gets the uninterpreted raw value. Might be useful for some |
| 119 | // atomic operations. |
| 120 | func (n *Number) AsRaw() uint64 { |
| 121 | return uint64(*n) |
| 122 | } |
| 123 | |
| 124 | // AsInt64 assumes that the value contains an int64 and returns it as |
| 125 | // such. |
| 126 | func (n *Number) AsInt64() int64 { |
| 127 | return internal.RawToInt64(n.AsRaw()) |
| 128 | } |
| 129 | |
| 130 | // AsFloat64 assumes that the measurement value contains a float64 and |
| 131 | // returns it as such. |
| 132 | func (n *Number) AsFloat64() float64 { |
| 133 | return internal.RawToFloat64(n.AsRaw()) |
| 134 | } |
| 135 | |
| 136 | // - as x atomic |
| 137 | |
| 138 | // AsNumberAtomic gets the Number atomically. |
| 139 | func (n *Number) AsNumberAtomic() Number { |
| 140 | return NewNumberFromRaw(n.AsRawAtomic()) |
| 141 | } |
| 142 | |
| 143 | // AsRawAtomic gets the uninterpreted raw value atomically. Might be |
| 144 | // useful for some atomic operations. |
| 145 | func (n *Number) AsRawAtomic() uint64 { |
| 146 | return atomic.LoadUint64(n.AsRawPtr()) |
| 147 | } |
| 148 | |
| 149 | // AsInt64Atomic assumes that the number contains an int64 and returns |
| 150 | // it as such atomically. |
| 151 | func (n *Number) AsInt64Atomic() int64 { |
| 152 | return atomic.LoadInt64(n.AsInt64Ptr()) |
| 153 | } |
| 154 | |
| 155 | // AsFloat64Atomic assumes that the measurement value contains a |
| 156 | // float64 and returns it as such atomically. |
| 157 | func (n *Number) AsFloat64Atomic() float64 { |
| 158 | return internal.RawToFloat64(n.AsRawAtomic()) |
| 159 | } |
| 160 | |
| 161 | // - as x ptr |
| 162 | |
| 163 | // AsRawPtr gets the pointer to the raw, uninterpreted raw |
| 164 | // value. Might be useful for some atomic operations. |
| 165 | func (n *Number) AsRawPtr() *uint64 { |
| 166 | return (*uint64)(n) |
| 167 | } |
| 168 | |
| 169 | // AsInt64Ptr assumes that the number contains an int64 and returns a |
| 170 | // pointer to it. |
| 171 | func (n *Number) AsInt64Ptr() *int64 { |
| 172 | return internal.RawPtrToInt64Ptr(n.AsRawPtr()) |
| 173 | } |
| 174 | |
| 175 | // AsFloat64Ptr assumes that the number contains a float64 and returns a |
| 176 | // pointer to it. |
| 177 | func (n *Number) AsFloat64Ptr() *float64 { |
| 178 | return internal.RawPtrToFloat64Ptr(n.AsRawPtr()) |
| 179 | } |
| 180 | |
| 181 | // - coerce |
| 182 | |
| 183 | // CoerceToInt64 casts the number to int64. May result in |
| 184 | // data/precision loss. |
| 185 | func (n *Number) CoerceToInt64(kind NumberKind) int64 { |
| 186 | switch kind { |
| 187 | case Int64NumberKind: |
| 188 | return n.AsInt64() |
| 189 | case Float64NumberKind: |
| 190 | return int64(n.AsFloat64()) |
| 191 | default: |
| 192 | // you get what you deserve |
| 193 | return 0 |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | // CoerceToFloat64 casts the number to float64. May result in |
| 198 | // data/precision loss. |
| 199 | func (n *Number) CoerceToFloat64(kind NumberKind) float64 { |
| 200 | switch kind { |
| 201 | case Int64NumberKind: |
| 202 | return float64(n.AsInt64()) |
| 203 | case Float64NumberKind: |
| 204 | return n.AsFloat64() |
| 205 | default: |
| 206 | // you get what you deserve |
| 207 | return 0 |
| 208 | } |
| 209 | } |
| 210 | |
| 211 | // - set |
| 212 | |
| 213 | // SetNumber sets the number to the passed number. Both should be of |
| 214 | // the same kind. |
| 215 | func (n *Number) SetNumber(nn Number) { |
| 216 | *n.AsRawPtr() = nn.AsRaw() |
| 217 | } |
| 218 | |
| 219 | // SetRaw sets the number to the passed raw value. Both number and the |
| 220 | // raw number should represent the same kind. |
| 221 | func (n *Number) SetRaw(r uint64) { |
| 222 | *n.AsRawPtr() = r |
| 223 | } |
| 224 | |
| 225 | // SetInt64 assumes that the number contains an int64 and sets it to |
| 226 | // the passed value. |
| 227 | func (n *Number) SetInt64(i int64) { |
| 228 | *n.AsInt64Ptr() = i |
| 229 | } |
| 230 | |
| 231 | // SetFloat64 assumes that the number contains a float64 and sets it |
| 232 | // to the passed value. |
| 233 | func (n *Number) SetFloat64(f float64) { |
| 234 | *n.AsFloat64Ptr() = f |
| 235 | } |
| 236 | |
| 237 | // - set atomic |
| 238 | |
| 239 | // SetNumberAtomic sets the number to the passed number |
| 240 | // atomically. Both should be of the same kind. |
| 241 | func (n *Number) SetNumberAtomic(nn Number) { |
| 242 | atomic.StoreUint64(n.AsRawPtr(), nn.AsRaw()) |
| 243 | } |
| 244 | |
| 245 | // SetRawAtomic sets the number to the passed raw value |
| 246 | // atomically. Both number and the raw number should represent the |
| 247 | // same kind. |
| 248 | func (n *Number) SetRawAtomic(r uint64) { |
| 249 | atomic.StoreUint64(n.AsRawPtr(), r) |
| 250 | } |
| 251 | |
| 252 | // SetInt64Atomic assumes that the number contains an int64 and sets |
| 253 | // it to the passed value atomically. |
| 254 | func (n *Number) SetInt64Atomic(i int64) { |
| 255 | atomic.StoreInt64(n.AsInt64Ptr(), i) |
| 256 | } |
| 257 | |
| 258 | // SetFloat64Atomic assumes that the number contains a float64 and |
| 259 | // sets it to the passed value atomically. |
| 260 | func (n *Number) SetFloat64Atomic(f float64) { |
| 261 | atomic.StoreUint64(n.AsRawPtr(), internal.Float64ToRaw(f)) |
| 262 | } |
| 263 | |
| 264 | // - swap |
| 265 | |
| 266 | // SwapNumber sets the number to the passed number and returns the old |
| 267 | // number. Both this number and the passed number should be of the |
| 268 | // same kind. |
| 269 | func (n *Number) SwapNumber(nn Number) Number { |
| 270 | old := *n |
| 271 | n.SetNumber(nn) |
| 272 | return old |
| 273 | } |
| 274 | |
| 275 | // SwapRaw sets the number to the passed raw value and returns the old |
| 276 | // raw value. Both number and the raw number should represent the same |
| 277 | // kind. |
| 278 | func (n *Number) SwapRaw(r uint64) uint64 { |
| 279 | old := n.AsRaw() |
| 280 | n.SetRaw(r) |
| 281 | return old |
| 282 | } |
| 283 | |
| 284 | // SwapInt64 assumes that the number contains an int64, sets it to the |
| 285 | // passed value and returns the old int64 value. |
| 286 | func (n *Number) SwapInt64(i int64) int64 { |
| 287 | old := n.AsInt64() |
| 288 | n.SetInt64(i) |
| 289 | return old |
| 290 | } |
| 291 | |
| 292 | // SwapFloat64 assumes that the number contains an float64, sets it to |
| 293 | // the passed value and returns the old float64 value. |
| 294 | func (n *Number) SwapFloat64(f float64) float64 { |
| 295 | old := n.AsFloat64() |
| 296 | n.SetFloat64(f) |
| 297 | return old |
| 298 | } |
| 299 | |
| 300 | // - swap atomic |
| 301 | |
| 302 | // SwapNumberAtomic sets the number to the passed number and returns |
| 303 | // the old number atomically. Both this number and the passed number |
| 304 | // should be of the same kind. |
| 305 | func (n *Number) SwapNumberAtomic(nn Number) Number { |
| 306 | return NewNumberFromRaw(atomic.SwapUint64(n.AsRawPtr(), nn.AsRaw())) |
| 307 | } |
| 308 | |
| 309 | // SwapRawAtomic sets the number to the passed raw value and returns |
| 310 | // the old raw value atomically. Both number and the raw number should |
| 311 | // represent the same kind. |
| 312 | func (n *Number) SwapRawAtomic(r uint64) uint64 { |
| 313 | return atomic.SwapUint64(n.AsRawPtr(), r) |
| 314 | } |
| 315 | |
| 316 | // SwapInt64Atomic assumes that the number contains an int64, sets it |
| 317 | // to the passed value and returns the old int64 value atomically. |
| 318 | func (n *Number) SwapInt64Atomic(i int64) int64 { |
| 319 | return atomic.SwapInt64(n.AsInt64Ptr(), i) |
| 320 | } |
| 321 | |
| 322 | // SwapFloat64Atomic assumes that the number contains an float64, sets |
| 323 | // it to the passed value and returns the old float64 value |
| 324 | // atomically. |
| 325 | func (n *Number) SwapFloat64Atomic(f float64) float64 { |
| 326 | return internal.RawToFloat64(atomic.SwapUint64(n.AsRawPtr(), internal.Float64ToRaw(f))) |
| 327 | } |
| 328 | |
| 329 | // - add |
| 330 | |
| 331 | // AddNumber assumes that this and the passed number are of the passed |
| 332 | // kind and adds the passed number to this number. |
| 333 | func (n *Number) AddNumber(kind NumberKind, nn Number) { |
| 334 | switch kind { |
| 335 | case Int64NumberKind: |
| 336 | n.AddInt64(nn.AsInt64()) |
| 337 | case Float64NumberKind: |
| 338 | n.AddFloat64(nn.AsFloat64()) |
| 339 | } |
| 340 | } |
| 341 | |
| 342 | // AddRaw assumes that this number and the passed raw value are of the |
| 343 | // passed kind and adds the passed raw value to this number. |
| 344 | func (n *Number) AddRaw(kind NumberKind, r uint64) { |
| 345 | n.AddNumber(kind, NewNumberFromRaw(r)) |
| 346 | } |
| 347 | |
| 348 | // AddInt64 assumes that the number contains an int64 and adds the |
| 349 | // passed int64 to it. |
| 350 | func (n *Number) AddInt64(i int64) { |
| 351 | *n.AsInt64Ptr() += i |
| 352 | } |
| 353 | |
| 354 | // AddFloat64 assumes that the number contains a float64 and adds the |
| 355 | // passed float64 to it. |
| 356 | func (n *Number) AddFloat64(f float64) { |
| 357 | *n.AsFloat64Ptr() += f |
| 358 | } |
| 359 | |
| 360 | // - add atomic |
| 361 | |
| 362 | // AddNumberAtomic assumes that this and the passed number are of the |
| 363 | // passed kind and adds the passed number to this number atomically. |
| 364 | func (n *Number) AddNumberAtomic(kind NumberKind, nn Number) { |
| 365 | switch kind { |
| 366 | case Int64NumberKind: |
| 367 | n.AddInt64Atomic(nn.AsInt64()) |
| 368 | case Float64NumberKind: |
| 369 | n.AddFloat64Atomic(nn.AsFloat64()) |
| 370 | } |
| 371 | } |
| 372 | |
| 373 | // AddRawAtomic assumes that this number and the passed raw value are |
| 374 | // of the passed kind and adds the passed raw value to this number |
| 375 | // atomically. |
| 376 | func (n *Number) AddRawAtomic(kind NumberKind, r uint64) { |
| 377 | n.AddNumberAtomic(kind, NewNumberFromRaw(r)) |
| 378 | } |
| 379 | |
| 380 | // AddInt64Atomic assumes that the number contains an int64 and adds |
| 381 | // the passed int64 to it atomically. |
| 382 | func (n *Number) AddInt64Atomic(i int64) { |
| 383 | atomic.AddInt64(n.AsInt64Ptr(), i) |
| 384 | } |
| 385 | |
| 386 | // AddFloat64Atomic assumes that the number contains a float64 and |
| 387 | // adds the passed float64 to it atomically. |
| 388 | func (n *Number) AddFloat64Atomic(f float64) { |
| 389 | for { |
| 390 | o := n.AsFloat64Atomic() |
| 391 | if n.CompareAndSwapFloat64(o, o+f) { |
| 392 | break |
| 393 | } |
| 394 | } |
| 395 | } |
| 396 | |
| 397 | // - compare and swap (atomic only) |
| 398 | |
| 399 | // CompareAndSwapNumber does the atomic CAS operation on this |
| 400 | // number. This number and passed old and new numbers should be of the |
| 401 | // same kind. |
| 402 | func (n *Number) CompareAndSwapNumber(on, nn Number) bool { |
| 403 | return atomic.CompareAndSwapUint64(n.AsRawPtr(), on.AsRaw(), nn.AsRaw()) |
| 404 | } |
| 405 | |
| 406 | // CompareAndSwapRaw does the atomic CAS operation on this |
| 407 | // number. This number and passed old and new raw values should be of |
| 408 | // the same kind. |
| 409 | func (n *Number) CompareAndSwapRaw(or, nr uint64) bool { |
| 410 | return atomic.CompareAndSwapUint64(n.AsRawPtr(), or, nr) |
| 411 | } |
| 412 | |
| 413 | // CompareAndSwapInt64 assumes that this number contains an int64 and |
| 414 | // does the atomic CAS operation on it. |
| 415 | func (n *Number) CompareAndSwapInt64(oi, ni int64) bool { |
| 416 | return atomic.CompareAndSwapInt64(n.AsInt64Ptr(), oi, ni) |
| 417 | } |
| 418 | |
| 419 | // CompareAndSwapFloat64 assumes that this number contains a float64 and |
| 420 | // does the atomic CAS operation on it. |
| 421 | func (n *Number) CompareAndSwapFloat64(of, nf float64) bool { |
| 422 | return atomic.CompareAndSwapUint64(n.AsRawPtr(), internal.Float64ToRaw(of), internal.Float64ToRaw(nf)) |
| 423 | } |
| 424 | |
| 425 | // - compare |
| 426 | |
| 427 | // CompareNumber compares two Numbers given their kind. Both numbers |
| 428 | // should have the same kind. This returns: |
| 429 | // 0 if the numbers are equal |
| 430 | // -1 if the subject `n` is less than the argument `nn` |
| 431 | // +1 if the subject `n` is greater than the argument `nn` |
| 432 | func (n *Number) CompareNumber(kind NumberKind, nn Number) int { |
| 433 | switch kind { |
| 434 | case Int64NumberKind: |
| 435 | return n.CompareInt64(nn.AsInt64()) |
| 436 | case Float64NumberKind: |
| 437 | return n.CompareFloat64(nn.AsFloat64()) |
| 438 | default: |
| 439 | // you get what you deserve |
| 440 | return 0 |
| 441 | } |
| 442 | } |
| 443 | |
| 444 | // CompareRaw compares two numbers, where one is input as a raw |
| 445 | // uint64, interpreting both values as a `kind` of number. |
| 446 | func (n *Number) CompareRaw(kind NumberKind, r uint64) int { |
| 447 | return n.CompareNumber(kind, NewNumberFromRaw(r)) |
| 448 | } |
| 449 | |
| 450 | // CompareInt64 assumes that the Number contains an int64 and performs |
| 451 | // a comparison between the value and the other value. It returns the |
| 452 | // typical result of the compare function: -1 if the value is less |
| 453 | // than the other, 0 if both are equal, 1 if the value is greater than |
| 454 | // the other. |
| 455 | func (n *Number) CompareInt64(i int64) int { |
| 456 | this := n.AsInt64() |
| 457 | if this < i { |
| 458 | return -1 |
| 459 | } else if this > i { |
| 460 | return 1 |
| 461 | } |
| 462 | return 0 |
| 463 | } |
| 464 | |
| 465 | // CompareFloat64 assumes that the Number contains a float64 and |
| 466 | // performs a comparison between the value and the other value. It |
| 467 | // returns the typical result of the compare function: -1 if the value |
| 468 | // is less than the other, 0 if both are equal, 1 if the value is |
| 469 | // greater than the other. |
| 470 | // |
| 471 | // Do not compare NaN values. |
| 472 | func (n *Number) CompareFloat64(f float64) int { |
| 473 | this := n.AsFloat64() |
| 474 | if this < f { |
| 475 | return -1 |
| 476 | } else if this > f { |
| 477 | return 1 |
| 478 | } |
| 479 | return 0 |
| 480 | } |
| 481 | |
| 482 | // - relations to zero |
| 483 | |
| 484 | // IsPositive returns true if the actual value is greater than zero. |
| 485 | func (n *Number) IsPositive(kind NumberKind) bool { |
| 486 | return n.compareWithZero(kind) > 0 |
| 487 | } |
| 488 | |
| 489 | // IsNegative returns true if the actual value is less than zero. |
| 490 | func (n *Number) IsNegative(kind NumberKind) bool { |
| 491 | return n.compareWithZero(kind) < 0 |
| 492 | } |
| 493 | |
| 494 | // IsZero returns true if the actual value is equal to zero. |
| 495 | func (n *Number) IsZero(kind NumberKind) bool { |
| 496 | return n.compareWithZero(kind) == 0 |
| 497 | } |
| 498 | |
| 499 | // - misc |
| 500 | |
| 501 | // Emit returns a string representation of the raw value of the |
| 502 | // Number. A %d is used for integral values, %f for floating point |
| 503 | // values. |
| 504 | func (n *Number) Emit(kind NumberKind) string { |
| 505 | switch kind { |
| 506 | case Int64NumberKind: |
| 507 | return fmt.Sprintf("%d", n.AsInt64()) |
| 508 | case Float64NumberKind: |
| 509 | return fmt.Sprintf("%f", n.AsFloat64()) |
| 510 | default: |
| 511 | return "" |
| 512 | } |
| 513 | } |
| 514 | |
| 515 | // AsInterface returns the number as an interface{}, typically used |
| 516 | // for NumberKind-correct JSON conversion. |
| 517 | func (n *Number) AsInterface(kind NumberKind) interface{} { |
| 518 | switch kind { |
| 519 | case Int64NumberKind: |
| 520 | return n.AsInt64() |
| 521 | case Float64NumberKind: |
| 522 | return n.AsFloat64() |
| 523 | default: |
| 524 | return math.NaN() |
| 525 | } |
| 526 | } |
| 527 | |
| 528 | // - private stuff |
| 529 | |
| 530 | func (n *Number) compareWithZero(kind NumberKind) int { |
| 531 | switch kind { |
| 532 | case Int64NumberKind: |
| 533 | return n.CompareInt64(0) |
| 534 | case Float64NumberKind: |
| 535 | return n.CompareFloat64(0.) |
| 536 | default: |
| 537 | // you get what you deserve |
| 538 | return 0 |
| 539 | } |
| 540 | } |