1package msgp 2 3import ( 4 "io" 5 "math" 6 "sync" 7 "time" 8 9 "github.com/philhofer/fwd" 10) 11 12// where we keep old *Readers 13var readerPool = sync.Pool{New: func() interface{} { return &Reader{} }} 14 15// Type is a MessagePack wire type, 16// including this package's built-in 17// extension types. 18type Type byte 19 20// MessagePack Types 21// 22// The zero value of Type 23// is InvalidType. 24const ( 25 InvalidType Type = iota 26 27 // MessagePack built-in types 28 29 StrType 30 BinType 31 MapType 32 ArrayType 33 Float64Type 34 Float32Type 35 BoolType 36 IntType 37 UintType 38 NilType 39 ExtensionType 40 41 // pseudo-types provided 42 // by extensions 43 44 Complex64Type 45 Complex128Type 46 TimeType 47 48 _maxtype 49) 50 51// String implements fmt.Stringer 52func (t Type) String() string { 53 switch t { 54 case StrType: 55 return "str" 56 case BinType: 57 return "bin" 58 case MapType: 59 return "map" 60 case ArrayType: 61 return "array" 62 case Float64Type: 63 return "float64" 64 case Float32Type: 65 return "float32" 66 case BoolType: 67 return "bool" 68 case UintType: 69 return "uint" 70 case IntType: 71 return "int" 72 case ExtensionType: 73 return "ext" 74 case NilType: 75 return "nil" 76 default: 77 return "<invalid>" 78 } 79} 80 81func freeR(m *Reader) { 82 readerPool.Put(m) 83} 84 85// Unmarshaler is the interface fulfilled 86// by objects that know how to unmarshal 87// themselves from MessagePack. 88// UnmarshalMsg unmarshals the object 89// from binary, returing any leftover 90// bytes and any errors encountered. 91type Unmarshaler interface { 92 UnmarshalMsg([]byte) ([]byte, error) 93} 94 95// Decodable is the interface fulfilled 96// by objects that know how to read 97// themselves from a *Reader. 98type Decodable interface { 99 DecodeMsg(*Reader) error 100} 101 102// Decode decodes 'd' from 'r'. 103func Decode(r io.Reader, d Decodable) error { 104 rd := NewReader(r) 105 err := d.DecodeMsg(rd) 106 freeR(rd) 107 return err 108} 109 110// NewReader returns a *Reader that 111// reads from the provided reader. The 112// reader will be buffered. 113func NewReader(r io.Reader) *Reader { 114 p := readerPool.Get().(*Reader) 115 if p.R == nil { 116 p.R = fwd.NewReader(r) 117 } else { 118 p.R.Reset(r) 119 } 120 return p 121} 122 123// NewReaderSize returns a *Reader with a buffer of the given size. 124// (This is vastly preferable to passing the decoder a reader that is already buffered.) 125func NewReaderSize(r io.Reader, sz int) *Reader { 126 return &Reader{R: fwd.NewReaderSize(r, sz)} 127} 128 129// Reader wraps an io.Reader and provides 130// methods to read MessagePack-encoded values 131// from it. Readers are buffered. 132type Reader struct { 133 // R is the buffered reader 134 // that the Reader uses 135 // to decode MessagePack. 136 // The Reader itself 137 // is stateless; all the 138 // buffering is done 139 // within R. 140 R *fwd.Reader 141 scratch []byte 142} 143 144// Read implements `io.Reader` 145func (m *Reader) Read(p []byte) (int, error) { 146 return m.R.Read(p) 147} 148 149// CopyNext reads the next object from m without decoding it and writes it to w. 150// It avoids unnecessary copies internally. 151func (m *Reader) CopyNext(w io.Writer) (int64, error) { 152 sz, o, err := getNextSize(m.R) 153 if err != nil { 154 return 0, err 155 } 156 157 var n int64 158 // Opportunistic optimization: if we can fit the whole thing in the m.R 159 // buffer, then just get a pointer to that, and pass it to w.Write, 160 // avoiding an allocation. 161 if int(sz) <= m.R.BufferSize() { 162 var nn int 163 var buf []byte 164 buf, err = m.R.Next(int(sz)) 165 if err != nil { 166 if err == io.ErrUnexpectedEOF { 167 err = ErrShortBytes 168 } 169 return 0, err 170 } 171 nn, err = w.Write(buf) 172 n += int64(nn) 173 } else { 174 // Fall back to io.CopyN. 175 // May avoid allocating if w is a ReaderFrom (e.g. bytes.Buffer) 176 n, err = io.CopyN(w, m.R, int64(sz)) 177 if err == io.ErrUnexpectedEOF { 178 err = ErrShortBytes 179 } 180 } 181 if err != nil { 182 return n, err 183 } else if n < int64(sz) { 184 return n, io.ErrShortWrite 185 } 186 187 // for maps and slices, read elements 188 for x := uintptr(0); x < o; x++ { 189 var n2 int64 190 n2, err = m.CopyNext(w) 191 if err != nil { 192 return n, err 193 } 194 n += n2 195 } 196 return n, nil 197} 198 199// ReadFull implements `io.ReadFull` 200func (m *Reader) ReadFull(p []byte) (int, error) { 201 return m.R.ReadFull(p) 202} 203 204// Reset resets the underlying reader. 205func (m *Reader) Reset(r io.Reader) { m.R.Reset(r) } 206 207// Buffered returns the number of bytes currently in the read buffer. 208func (m *Reader) Buffered() int { return m.R.Buffered() } 209 210// BufferSize returns the capacity of the read buffer. 211func (m *Reader) BufferSize() int { return m.R.BufferSize() } 212 213// NextType returns the next object type to be decoded. 214func (m *Reader) NextType() (Type, error) { 215 p, err := m.R.Peek(1) 216 if err != nil { 217 return InvalidType, err 218 } 219 t := getType(p[0]) 220 if t == InvalidType { 221 return t, InvalidPrefixError(p[0]) 222 } 223 if t == ExtensionType { 224 v, err := m.peekExtensionType() 225 if err != nil { 226 return InvalidType, err 227 } 228 switch v { 229 case Complex64Extension: 230 return Complex64Type, nil 231 case Complex128Extension: 232 return Complex128Type, nil 233 case TimeExtension: 234 return TimeType, nil 235 } 236 } 237 return t, nil 238} 239 240// IsNil returns whether or not 241// the next byte is a null messagepack byte 242func (m *Reader) IsNil() bool { 243 p, err := m.R.Peek(1) 244 return err == nil && p[0] == mnil 245} 246 247// getNextSize returns the size of the next object on the wire. 248// returns (obj size, obj elements, error) 249// only maps and arrays have non-zero obj elements 250// for maps and arrays, obj size does not include elements 251// 252// use uintptr b/c it's guaranteed to be large enough 253// to hold whatever we can fit in memory. 254func getNextSize(r *fwd.Reader) (uintptr, uintptr, error) { 255 b, err := r.Peek(1) 256 if err != nil { 257 return 0, 0, err 258 } 259 lead := b[0] 260 spec := &sizes[lead] 261 size, mode := spec.size, spec.extra 262 if size == 0 { 263 return 0, 0, InvalidPrefixError(lead) 264 } 265 if mode >= 0 { 266 return uintptr(size), uintptr(mode), nil 267 } 268 b, err = r.Peek(int(size)) 269 if err != nil { 270 return 0, 0, err 271 } 272 switch mode { 273 case extra8: 274 return uintptr(size) + uintptr(b[1]), 0, nil 275 case extra16: 276 return uintptr(size) + uintptr(big.Uint16(b[1:])), 0, nil 277 case extra32: 278 return uintptr(size) + uintptr(big.Uint32(b[1:])), 0, nil 279 case map16v: 280 return uintptr(size), 2 * uintptr(big.Uint16(b[1:])), nil 281 case map32v: 282 return uintptr(size), 2 * uintptr(big.Uint32(b[1:])), nil 283 case array16v: 284 return uintptr(size), uintptr(big.Uint16(b[1:])), nil 285 case array32v: 286 return uintptr(size), uintptr(big.Uint32(b[1:])), nil 287 default: 288 return 0, 0, fatal 289 } 290} 291 292// Skip skips over the next object, regardless of 293// its type. If it is an array or map, the whole array 294// or map will be skipped. 295func (m *Reader) Skip() error { 296 var ( 297 v uintptr // bytes 298 o uintptr // objects 299 err error 300 p []byte 301 ) 302 303 // we can use the faster 304 // method if we have enough 305 // buffered data 306 if m.R.Buffered() >= 5 { 307 p, err = m.R.Peek(5) 308 if err != nil { 309 return err 310 } 311 v, o, err = getSize(p) 312 if err != nil { 313 return err 314 } 315 } else { 316 v, o, err = getNextSize(m.R) 317 if err != nil { 318 return err 319 } 320 } 321 322 // 'v' is always non-zero 323 // if err == nil 324 _, err = m.R.Skip(int(v)) 325 if err != nil { 326 return err 327 } 328 329 // for maps and slices, skip elements 330 for x := uintptr(0); x < o; x++ { 331 err = m.Skip() 332 if err != nil { 333 return err 334 } 335 } 336 return nil 337} 338 339// ReadMapHeader reads the next object 340// as a map header and returns the size 341// of the map and the number of bytes written. 342// It will return a TypeError{} if the next 343// object is not a map. 344func (m *Reader) ReadMapHeader() (sz uint32, err error) { 345 var p []byte 346 var lead byte 347 p, err = m.R.Peek(1) 348 if err != nil { 349 return 350 } 351 lead = p[0] 352 if isfixmap(lead) { 353 sz = uint32(rfixmap(lead)) 354 _, err = m.R.Skip(1) 355 return 356 } 357 switch lead { 358 case mmap16: 359 p, err = m.R.Next(3) 360 if err != nil { 361 return 362 } 363 sz = uint32(big.Uint16(p[1:])) 364 return 365 case mmap32: 366 p, err = m.R.Next(5) 367 if err != nil { 368 return 369 } 370 sz = big.Uint32(p[1:]) 371 return 372 default: 373 err = badPrefix(MapType, lead) 374 return 375 } 376} 377 378// ReadMapKey reads either a 'str' or 'bin' field from 379// the reader and returns the value as a []byte. It uses 380// scratch for storage if it is large enough. 381func (m *Reader) ReadMapKey(scratch []byte) ([]byte, error) { 382 out, err := m.ReadStringAsBytes(scratch) 383 if err != nil { 384 if tperr, ok := err.(TypeError); ok && tperr.Encoded == BinType { 385 return m.ReadBytes(scratch) 386 } 387 return nil, err 388 } 389 return out, nil 390} 391 392// MapKeyPtr returns a []byte pointing to the contents 393// of a valid map key. The key cannot be empty, and it 394// must be shorter than the total buffer size of the 395// *Reader. Additionally, the returned slice is only 396// valid until the next *Reader method call. Users 397// should exercise extreme care when using this 398// method; writing into the returned slice may 399// corrupt future reads. 400func (m *Reader) ReadMapKeyPtr() ([]byte, error) { 401 p, err := m.R.Peek(1) 402 if err != nil { 403 return nil, err 404 } 405 lead := p[0] 406 var read int 407 if isfixstr(lead) { 408 read = int(rfixstr(lead)) 409 m.R.Skip(1) 410 goto fill 411 } 412 switch lead { 413 case mstr8, mbin8: 414 p, err = m.R.Next(2) 415 if err != nil { 416 return nil, err 417 } 418 read = int(p[1]) 419 case mstr16, mbin16: 420 p, err = m.R.Next(3) 421 if err != nil { 422 return nil, err 423 } 424 read = int(big.Uint16(p[1:])) 425 case mstr32, mbin32: 426 p, err = m.R.Next(5) 427 if err != nil { 428 return nil, err 429 } 430 read = int(big.Uint32(p[1:])) 431 default: 432 return nil, badPrefix(StrType, lead) 433 } 434fill: 435 if read == 0 { 436 return nil, ErrShortBytes 437 } 438 return m.R.Next(read) 439} 440 441// ReadArrayHeader reads the next object as an 442// array header and returns the size of the array 443// and the number of bytes read. 444func (m *Reader) ReadArrayHeader() (sz uint32, err error) { 445 var lead byte 446 var p []byte 447 p, err = m.R.Peek(1) 448 if err != nil { 449 return 450 } 451 lead = p[0] 452 if isfixarray(lead) { 453 sz = uint32(rfixarray(lead)) 454 _, err = m.R.Skip(1) 455 return 456 } 457 switch lead { 458 case marray16: 459 p, err = m.R.Next(3) 460 if err != nil { 461 return 462 } 463 sz = uint32(big.Uint16(p[1:])) 464 return 465 466 case marray32: 467 p, err = m.R.Next(5) 468 if err != nil { 469 return 470 } 471 sz = big.Uint32(p[1:]) 472 return 473 474 default: 475 err = badPrefix(ArrayType, lead) 476 return 477 } 478} 479 480// ReadNil reads a 'nil' MessagePack byte from the reader 481func (m *Reader) ReadNil() error { 482 p, err := m.R.Peek(1) 483 if err != nil { 484 return err 485 } 486 if p[0] != mnil { 487 return badPrefix(NilType, p[0]) 488 } 489 _, err = m.R.Skip(1) 490 return err 491} 492 493// ReadFloat64 reads a float64 from the reader. 494// (If the value on the wire is encoded as a float32, 495// it will be up-cast to a float64.) 496func (m *Reader) ReadFloat64() (f float64, err error) { 497 var p []byte 498 p, err = m.R.Peek(9) 499 if err != nil { 500 // we'll allow a coversion from float32 to float64, 501 // since we don't lose any precision 502 if err == io.EOF && len(p) > 0 && p[0] == mfloat32 { 503 ef, err := m.ReadFloat32() 504 return float64(ef), err 505 } 506 return 507 } 508 if p[0] != mfloat64 { 509 // see above 510 if p[0] == mfloat32 { 511 ef, err := m.ReadFloat32() 512 return float64(ef), err 513 } 514 err = badPrefix(Float64Type, p[0]) 515 return 516 } 517 f = math.Float64frombits(getMuint64(p)) 518 _, err = m.R.Skip(9) 519 return 520} 521 522// ReadFloat32 reads a float32 from the reader 523func (m *Reader) ReadFloat32() (f float32, err error) { 524 var p []byte 525 p, err = m.R.Peek(5) 526 if err != nil { 527 return 528 } 529 if p[0] != mfloat32 { 530 err = badPrefix(Float32Type, p[0]) 531 return 532 } 533 f = math.Float32frombits(getMuint32(p)) 534 _, err = m.R.Skip(5) 535 return 536} 537 538// ReadBool reads a bool from the reader 539func (m *Reader) ReadBool() (b bool, err error) { 540 var p []byte 541 p, err = m.R.Peek(1) 542 if err != nil { 543 return 544 } 545 switch p[0] { 546 case mtrue: 547 b = true 548 case mfalse: 549 default: 550 err = badPrefix(BoolType, p[0]) 551 return 552 } 553 _, err = m.R.Skip(1) 554 return 555} 556 557// ReadInt64 reads an int64 from the reader 558func (m *Reader) ReadInt64() (i int64, err error) { 559 var p []byte 560 var lead byte 561 p, err = m.R.Peek(1) 562 if err != nil { 563 return 564 } 565 lead = p[0] 566 567 if isfixint(lead) { 568 i = int64(rfixint(lead)) 569 _, err = m.R.Skip(1) 570 return 571 } else if isnfixint(lead) { 572 i = int64(rnfixint(lead)) 573 _, err = m.R.Skip(1) 574 return 575 } 576 577 switch lead { 578 case mint8: 579 p, err = m.R.Next(2) 580 if err != nil { 581 return 582 } 583 i = int64(getMint8(p)) 584 return 585 586 case mint16: 587 p, err = m.R.Next(3) 588 if err != nil { 589 return 590 } 591 i = int64(getMint16(p)) 592 return 593 594 case mint32: 595 p, err = m.R.Next(5) 596 if err != nil { 597 return 598 } 599 i = int64(getMint32(p)) 600 return 601 602 case mint64: 603 p, err = m.R.Next(9) 604 if err != nil { 605 return 606 } 607 i = getMint64(p) 608 return 609 610 default: 611 err = badPrefix(IntType, lead) 612 return 613 } 614} 615 616// ReadInt32 reads an int32 from the reader 617func (m *Reader) ReadInt32() (i int32, err error) { 618 var in int64 619 in, err = m.ReadInt64() 620 if in > math.MaxInt32 || in < math.MinInt32 { 621 err = IntOverflow{Value: in, FailedBitsize: 32} 622 return 623 } 624 i = int32(in) 625 return 626} 627 628// ReadInt16 reads an int16 from the reader 629func (m *Reader) ReadInt16() (i int16, err error) { 630 var in int64 631 in, err = m.ReadInt64() 632 if in > math.MaxInt16 || in < math.MinInt16 { 633 err = IntOverflow{Value: in, FailedBitsize: 16} 634 return 635 } 636 i = int16(in) 637 return 638} 639 640// ReadInt8 reads an int8 from the reader 641func (m *Reader) ReadInt8() (i int8, err error) { 642 var in int64 643 in, err = m.ReadInt64() 644 if in > math.MaxInt8 || in < math.MinInt8 { 645 err = IntOverflow{Value: in, FailedBitsize: 8} 646 return 647 } 648 i = int8(in) 649 return 650} 651 652// ReadInt reads an int from the reader 653func (m *Reader) ReadInt() (i int, err error) { 654 if smallint { 655 var in int32 656 in, err = m.ReadInt32() 657 i = int(in) 658 return 659 } 660 var in int64 661 in, err = m.ReadInt64() 662 i = int(in) 663 return 664} 665 666// ReadUint64 reads a uint64 from the reader 667func (m *Reader) ReadUint64() (u uint64, err error) { 668 var p []byte 669 var lead byte 670 p, err = m.R.Peek(1) 671 if err != nil { 672 return 673 } 674 lead = p[0] 675 if isfixint(lead) { 676 u = uint64(rfixint(lead)) 677 _, err = m.R.Skip(1) 678 return 679 } 680 switch lead { 681 case muint8: 682 p, err = m.R.Next(2) 683 if err != nil { 684 return 685 } 686 u = uint64(getMuint8(p)) 687 return 688 689 case muint16: 690 p, err = m.R.Next(3) 691 if err != nil { 692 return 693 } 694 u = uint64(getMuint16(p)) 695 return 696 697 case muint32: 698 p, err = m.R.Next(5) 699 if err != nil { 700 return 701 } 702 u = uint64(getMuint32(p)) 703 return 704 705 case muint64: 706 p, err = m.R.Next(9) 707 if err != nil { 708 return 709 } 710 u = getMuint64(p) 711 return 712 713 default: 714 err = badPrefix(UintType, lead) 715 return 716 717 } 718} 719 720// ReadUint32 reads a uint32 from the reader 721func (m *Reader) ReadUint32() (u uint32, err error) { 722 var in uint64 723 in, err = m.ReadUint64() 724 if in > math.MaxUint32 { 725 err = UintOverflow{Value: in, FailedBitsize: 32} 726 return 727 } 728 u = uint32(in) 729 return 730} 731 732// ReadUint16 reads a uint16 from the reader 733func (m *Reader) ReadUint16() (u uint16, err error) { 734 var in uint64 735 in, err = m.ReadUint64() 736 if in > math.MaxUint16 { 737 err = UintOverflow{Value: in, FailedBitsize: 16} 738 return 739 } 740 u = uint16(in) 741 return 742} 743 744// ReadUint8 reads a uint8 from the reader 745func (m *Reader) ReadUint8() (u uint8, err error) { 746 var in uint64 747 in, err = m.ReadUint64() 748 if in > math.MaxUint8 { 749 err = UintOverflow{Value: in, FailedBitsize: 8} 750 return 751 } 752 u = uint8(in) 753 return 754} 755 756// ReadUint reads a uint from the reader 757func (m *Reader) ReadUint() (u uint, err error) { 758 if smallint { 759 var un uint32 760 un, err = m.ReadUint32() 761 u = uint(un) 762 return 763 } 764 var un uint64 765 un, err = m.ReadUint64() 766 u = uint(un) 767 return 768} 769 770// ReadByte is analogous to ReadUint8. 771// 772// NOTE: this is *not* an implementation 773// of io.ByteReader. 774func (m *Reader) ReadByte() (b byte, err error) { 775 var in uint64 776 in, err = m.ReadUint64() 777 if in > math.MaxUint8 { 778 err = UintOverflow{Value: in, FailedBitsize: 8} 779 return 780 } 781 b = byte(in) 782 return 783} 784 785// ReadBytes reads a MessagePack 'bin' object 786// from the reader and returns its value. It may 787// use 'scratch' for storage if it is non-nil. 788func (m *Reader) ReadBytes(scratch []byte) (b []byte, err error) { 789 var p []byte 790 var lead byte 791 p, err = m.R.Peek(2) 792 if err != nil { 793 return 794 } 795 lead = p[0] 796 var read int64 797 switch lead { 798 case mbin8: 799 read = int64(p[1]) 800 m.R.Skip(2) 801 case mbin16: 802 p, err = m.R.Next(3) 803 if err != nil { 804 return 805 } 806 read = int64(big.Uint16(p[1:])) 807 case mbin32: 808 p, err = m.R.Next(5) 809 if err != nil { 810 return 811 } 812 read = int64(big.Uint32(p[1:])) 813 default: 814 err = badPrefix(BinType, lead) 815 return 816 } 817 if int64(cap(scratch)) < read { 818 b = make([]byte, read) 819 } else { 820 b = scratch[0:read] 821 } 822 _, err = m.R.ReadFull(b) 823 return 824} 825 826// ReadBytesHeader reads the size header 827// of a MessagePack 'bin' object. The user 828// is responsible for dealing with the next 829// 'sz' bytes from the reader in an application-specific 830// way. 831func (m *Reader) ReadBytesHeader() (sz uint32, err error) { 832 var p []byte 833 p, err = m.R.Peek(1) 834 if err != nil { 835 return 836 } 837 switch p[0] { 838 case mbin8: 839 p, err = m.R.Next(2) 840 if err != nil { 841 return 842 } 843 sz = uint32(p[1]) 844 return 845 case mbin16: 846 p, err = m.R.Next(3) 847 if err != nil { 848 return 849 } 850 sz = uint32(big.Uint16(p[1:])) 851 return 852 case mbin32: 853 p, err = m.R.Next(5) 854 if err != nil { 855 return 856 } 857 sz = uint32(big.Uint32(p[1:])) 858 return 859 default: 860 err = badPrefix(BinType, p[0]) 861 return 862 } 863} 864 865// ReadExactBytes reads a MessagePack 'bin'-encoded 866// object off of the wire into the provided slice. An 867// ArrayError will be returned if the object is not 868// exactly the length of the input slice. 869func (m *Reader) ReadExactBytes(into []byte) error { 870 p, err := m.R.Peek(2) 871 if err != nil { 872 return err 873 } 874 lead := p[0] 875 var read int64 // bytes to read 876 var skip int // prefix size to skip 877 switch lead { 878 case mbin8: 879 read = int64(p[1]) 880 skip = 2 881 case mbin16: 882 p, err = m.R.Peek(3) 883 if err != nil { 884 return err 885 } 886 read = int64(big.Uint16(p[1:])) 887 skip = 3 888 case mbin32: 889 p, err = m.R.Peek(5) 890 if err != nil { 891 return err 892 } 893 read = int64(big.Uint32(p[1:])) 894 skip = 5 895 default: 896 return badPrefix(BinType, lead) 897 } 898 if read != int64(len(into)) { 899 return ArrayError{Wanted: uint32(len(into)), Got: uint32(read)} 900 } 901 m.R.Skip(skip) 902 _, err = m.R.ReadFull(into) 903 return err 904} 905 906// ReadStringAsBytes reads a MessagePack 'str' (utf-8) string 907// and returns its value as bytes. It may use 'scratch' for storage 908// if it is non-nil. 909func (m *Reader) ReadStringAsBytes(scratch []byte) (b []byte, err error) { 910 var p []byte 911 var lead byte 912 p, err = m.R.Peek(1) 913 if err != nil { 914 return 915 } 916 lead = p[0] 917 var read int64 918 919 if isfixstr(lead) { 920 read = int64(rfixstr(lead)) 921 m.R.Skip(1) 922 goto fill 923 } 924 925 switch lead { 926 case mstr8: 927 p, err = m.R.Next(2) 928 if err != nil { 929 return 930 } 931 read = int64(uint8(p[1])) 932 case mstr16: 933 p, err = m.R.Next(3) 934 if err != nil { 935 return 936 } 937 read = int64(big.Uint16(p[1:])) 938 case mstr32: 939 p, err = m.R.Next(5) 940 if err != nil { 941 return 942 } 943 read = int64(big.Uint32(p[1:])) 944 default: 945 err = badPrefix(StrType, lead) 946 return 947 } 948fill: 949 if int64(cap(scratch)) < read { 950 b = make([]byte, read) 951 } else { 952 b = scratch[0:read] 953 } 954 _, err = m.R.ReadFull(b) 955 return 956} 957 958// ReadStringHeader reads a string header 959// off of the wire. The user is then responsible 960// for dealing with the next 'sz' bytes from 961// the reader in an application-specific manner. 962func (m *Reader) ReadStringHeader() (sz uint32, err error) { 963 var p []byte 964 p, err = m.R.Peek(1) 965 if err != nil { 966 return 967 } 968 lead := p[0] 969 if isfixstr(lead) { 970 sz = uint32(rfixstr(lead)) 971 m.R.Skip(1) 972 return 973 } 974 switch lead { 975 case mstr8: 976 p, err = m.R.Next(2) 977 if err != nil { 978 return 979 } 980 sz = uint32(p[1]) 981 return 982 case mstr16: 983 p, err = m.R.Next(3) 984 if err != nil { 985 return 986 } 987 sz = uint32(big.Uint16(p[1:])) 988 return 989 case mstr32: 990 p, err = m.R.Next(5) 991 if err != nil { 992 return 993 } 994 sz = big.Uint32(p[1:]) 995 return 996 default: 997 err = badPrefix(StrType, lead) 998 return 999 } 1000} 1001 1002// ReadString reads a utf-8 string from the reader 1003func (m *Reader) ReadString() (s string, err error) { 1004 var p []byte 1005 var lead byte 1006 var read int64 1007 p, err = m.R.Peek(1) 1008 if err != nil { 1009 return 1010 } 1011 lead = p[0] 1012 1013 if isfixstr(lead) { 1014 read = int64(rfixstr(lead)) 1015 m.R.Skip(1) 1016 goto fill 1017 } 1018 1019 switch lead { 1020 case mstr8: 1021 p, err = m.R.Next(2) 1022 if err != nil { 1023 return 1024 } 1025 read = int64(uint8(p[1])) 1026 case mstr16: 1027 p, err = m.R.Next(3) 1028 if err != nil { 1029 return 1030 } 1031 read = int64(big.Uint16(p[1:])) 1032 case mstr32: 1033 p, err = m.R.Next(5) 1034 if err != nil { 1035 return 1036 } 1037 read = int64(big.Uint32(p[1:])) 1038 default: 1039 err = badPrefix(StrType, lead) 1040 return 1041 } 1042fill: 1043 if read == 0 { 1044 s, err = "", nil 1045 return 1046 } 1047 // reading into the memory 1048 // that will become the string 1049 // itself has vastly superior 1050 // worst-case performance, because 1051 // the reader buffer doesn't have 1052 // to be large enough to hold the string. 1053 // the idea here is to make it more 1054 // difficult for someone malicious 1055 // to cause the system to run out of 1056 // memory by sending very large strings. 1057 // 1058 // NOTE: this works because the argument 1059 // passed to (*fwd.Reader).ReadFull escapes 1060 // to the heap; its argument may, in turn, 1061 // be passed to the underlying reader, and 1062 // thus escape analysis *must* conclude that 1063 // 'out' escapes. 1064 out := make([]byte, read) 1065 _, err = m.R.ReadFull(out) 1066 if err != nil { 1067 return 1068 } 1069 s = UnsafeString(out) 1070 return 1071} 1072 1073// ReadComplex64 reads a complex64 from the reader 1074func (m *Reader) ReadComplex64() (f complex64, err error) { 1075 var p []byte 1076 p, err = m.R.Peek(10) 1077 if err != nil { 1078 return 1079 } 1080 if p[0] != mfixext8 { 1081 err = badPrefix(Complex64Type, p[0]) 1082 return 1083 } 1084 if int8(p[1]) != Complex64Extension { 1085 err = errExt(int8(p[1]), Complex64Extension) 1086 return 1087 } 1088 f = complex(math.Float32frombits(big.Uint32(p[2:])), 1089 math.Float32frombits(big.Uint32(p[6:]))) 1090 _, err = m.R.Skip(10) 1091 return 1092} 1093 1094// ReadComplex128 reads a complex128 from the reader 1095func (m *Reader) ReadComplex128() (f complex128, err error) { 1096 var p []byte 1097 p, err = m.R.Peek(18) 1098 if err != nil { 1099 return 1100 } 1101 if p[0] != mfixext16 { 1102 err = badPrefix(Complex128Type, p[0]) 1103 return 1104 } 1105 if int8(p[1]) != Complex128Extension { 1106 err = errExt(int8(p[1]), Complex128Extension) 1107 return 1108 } 1109 f = complex(math.Float64frombits(big.Uint64(p[2:])), 1110 math.Float64frombits(big.Uint64(p[10:]))) 1111 _, err = m.R.Skip(18) 1112 return 1113} 1114 1115// ReadMapStrIntf reads a MessagePack map into a map[string]interface{}. 1116// (You must pass a non-nil map into the function.) 1117func (m *Reader) ReadMapStrIntf(mp map[string]interface{}) (err error) { 1118 var sz uint32 1119 sz, err = m.ReadMapHeader() 1120 if err != nil { 1121 return 1122 } 1123 for key := range mp { 1124 delete(mp, key) 1125 } 1126 for i := uint32(0); i < sz; i++ { 1127 var key string 1128 var val interface{} 1129 key, err = m.ReadString() 1130 if err != nil { 1131 return 1132 } 1133 val, err = m.ReadIntf() 1134 if err != nil { 1135 return 1136 } 1137 mp[key] = val 1138 } 1139 return 1140} 1141 1142// ReadTime reads a time.Time object from the reader. 1143// The returned time's location will be set to time.Local. 1144func (m *Reader) ReadTime() (t time.Time, err error) { 1145 var p []byte 1146 p, err = m.R.Peek(15) 1147 if err != nil { 1148 return 1149 } 1150 if p[0] != mext8 || p[1] != 12 { 1151 err = badPrefix(TimeType, p[0]) 1152 return 1153 } 1154 if int8(p[2]) != TimeExtension { 1155 err = errExt(int8(p[2]), TimeExtension) 1156 return 1157 } 1158 sec, nsec := getUnix(p[3:]) 1159 t = time.Unix(sec, int64(nsec)).Local() 1160 _, err = m.R.Skip(15) 1161 return 1162} 1163 1164// ReadIntf reads out the next object as a raw interface{}. 1165// Arrays are decoded as []interface{}, and maps are decoded 1166// as map[string]interface{}. Integers are decoded as int64 1167// and unsigned integers are decoded as uint64. 1168func (m *Reader) ReadIntf() (i interface{}, err error) { 1169 var t Type 1170 t, err = m.NextType() 1171 if err != nil { 1172 return 1173 } 1174 switch t { 1175 case BoolType: 1176 i, err = m.ReadBool() 1177 return 1178 1179 case IntType: 1180 i, err = m.ReadInt64() 1181 return 1182 1183 case UintType: 1184 i, err = m.ReadUint64() 1185 return 1186 1187 case BinType: 1188 i, err = m.ReadBytes(nil) 1189 return 1190 1191 case StrType: 1192 i, err = m.ReadString() 1193 return 1194 1195 case Complex64Type: 1196 i, err = m.ReadComplex64() 1197 return 1198 1199 case Complex128Type: 1200 i, err = m.ReadComplex128() 1201 return 1202 1203 case TimeType: 1204 i, err = m.ReadTime() 1205 return 1206 1207 case ExtensionType: 1208 var t int8 1209 t, err = m.peekExtensionType() 1210 if err != nil { 1211 return 1212 } 1213 f, ok := extensionReg[t] 1214 if ok { 1215 e := f() 1216 err = m.ReadExtension(e) 1217 i = e 1218 return 1219 } 1220 var e RawExtension 1221 e.Type = t 1222 err = m.ReadExtension(&e) 1223 i = &e 1224 return 1225 1226 case MapType: 1227 mp := make(map[string]interface{}) 1228 err = m.ReadMapStrIntf(mp) 1229 i = mp 1230 return 1231 1232 case NilType: 1233 err = m.ReadNil() 1234 i = nil 1235 return 1236 1237 case Float32Type: 1238 i, err = m.ReadFloat32() 1239 return 1240 1241 case Float64Type: 1242 i, err = m.ReadFloat64() 1243 return 1244 1245 case ArrayType: 1246 var sz uint32 1247 sz, err = m.ReadArrayHeader() 1248 1249 if err != nil { 1250 return 1251 } 1252 out := make([]interface{}, int(sz)) 1253 for j := range out { 1254 out[j], err = m.ReadIntf() 1255 if err != nil { 1256 return 1257 } 1258 } 1259 i = out 1260 return 1261 1262 default: 1263 return nil, fatal // unreachable 1264 } 1265} 1266