diff options
Diffstat (limited to 'vendor/gopkg.in/mgo.v2/bson/decode.go')
-rw-r--r-- | vendor/gopkg.in/mgo.v2/bson/decode.go | 844 |
1 files changed, 844 insertions, 0 deletions
diff --git a/vendor/gopkg.in/mgo.v2/bson/decode.go b/vendor/gopkg.in/mgo.v2/bson/decode.go new file mode 100644 index 0000000..9bd73f9 --- /dev/null +++ b/vendor/gopkg.in/mgo.v2/bson/decode.go @@ -0,0 +1,844 @@ +// BSON library for Go +// +// Copyright (c) 2010-2012 - Gustavo Niemeyer <gustavo@niemeyer.net> +// +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are met: +// +// 1. Redistributions of source code must retain the above copyright notice, this +// list of conditions and the following disclaimer. +// 2. Redistributions in binary form must reproduce the above copyright notice, +// this list of conditions and the following disclaimer in the documentation +// and/or other materials provided with the distribution. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND +// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR +// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND +// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS +// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +// gobson - BSON library for Go. + +package bson + +import ( + "fmt" + "math" + "net/url" + "reflect" + "strconv" + "sync" + "time" +) + +type decoder struct { + in []byte + i int + docType reflect.Type +} + +var typeM = reflect.TypeOf(M{}) + +func newDecoder(in []byte) *decoder { + return &decoder{in, 0, typeM} +} + +// -------------------------------------------------------------------------- +// Some helper functions. + +func corrupted() { + panic("Document is corrupted") +} + +func settableValueOf(i interface{}) reflect.Value { + v := reflect.ValueOf(i) + sv := reflect.New(v.Type()).Elem() + sv.Set(v) + return sv +} + +// -------------------------------------------------------------------------- +// Unmarshaling of documents. + +const ( + setterUnknown = iota + setterNone + setterType + setterAddr +) + +var setterStyles map[reflect.Type]int +var setterIface reflect.Type +var setterMutex sync.RWMutex + +func init() { + var iface Setter + setterIface = reflect.TypeOf(&iface).Elem() + setterStyles = make(map[reflect.Type]int) +} + +func setterStyle(outt reflect.Type) int { + setterMutex.RLock() + style := setterStyles[outt] + setterMutex.RUnlock() + if style == setterUnknown { + setterMutex.Lock() + defer setterMutex.Unlock() + if outt.Implements(setterIface) { + setterStyles[outt] = setterType + } else if reflect.PtrTo(outt).Implements(setterIface) { + setterStyles[outt] = setterAddr + } else { + setterStyles[outt] = setterNone + } + style = setterStyles[outt] + } + return style +} + +func getSetter(outt reflect.Type, out reflect.Value) Setter { + style := setterStyle(outt) + if style == setterNone { + return nil + } + if style == setterAddr { + if !out.CanAddr() { + return nil + } + out = out.Addr() + } else if outt.Kind() == reflect.Ptr && out.IsNil() { + out.Set(reflect.New(outt.Elem())) + } + return out.Interface().(Setter) +} + +func clearMap(m reflect.Value) { + var none reflect.Value + for _, k := range m.MapKeys() { + m.SetMapIndex(k, none) + } +} + +func (d *decoder) readDocTo(out reflect.Value) { + var elemType reflect.Type + outt := out.Type() + outk := outt.Kind() + + for { + if outk == reflect.Ptr && out.IsNil() { + out.Set(reflect.New(outt.Elem())) + } + if setter := getSetter(outt, out); setter != nil { + var raw Raw + d.readDocTo(reflect.ValueOf(&raw)) + err := setter.SetBSON(raw) + if _, ok := err.(*TypeError); err != nil && !ok { + panic(err) + } + return + } + if outk == reflect.Ptr { + out = out.Elem() + outt = out.Type() + outk = out.Kind() + continue + } + break + } + + var fieldsMap map[string]fieldInfo + var inlineMap reflect.Value + start := d.i + + origout := out + if outk == reflect.Interface { + if d.docType.Kind() == reflect.Map { + mv := reflect.MakeMap(d.docType) + out.Set(mv) + out = mv + } else { + dv := reflect.New(d.docType).Elem() + out.Set(dv) + out = dv + } + outt = out.Type() + outk = outt.Kind() + } + + docType := d.docType + keyType := typeString + convertKey := false + switch outk { + case reflect.Map: + keyType = outt.Key() + if keyType.Kind() != reflect.String { + panic("BSON map must have string keys. Got: " + outt.String()) + } + if keyType != typeString { + convertKey = true + } + elemType = outt.Elem() + if elemType == typeIface { + d.docType = outt + } + if out.IsNil() { + out.Set(reflect.MakeMap(out.Type())) + } else if out.Len() > 0 { + clearMap(out) + } + case reflect.Struct: + if outt != typeRaw { + sinfo, err := getStructInfo(out.Type()) + if err != nil { + panic(err) + } + fieldsMap = sinfo.FieldsMap + out.Set(sinfo.Zero) + if sinfo.InlineMap != -1 { + inlineMap = out.Field(sinfo.InlineMap) + if !inlineMap.IsNil() && inlineMap.Len() > 0 { + clearMap(inlineMap) + } + elemType = inlineMap.Type().Elem() + if elemType == typeIface { + d.docType = inlineMap.Type() + } + } + } + case reflect.Slice: + switch outt.Elem() { + case typeDocElem: + origout.Set(d.readDocElems(outt)) + return + case typeRawDocElem: + origout.Set(d.readRawDocElems(outt)) + return + } + fallthrough + default: + panic("Unsupported document type for unmarshalling: " + out.Type().String()) + } + + end := int(d.readInt32()) + end += d.i - 4 + if end <= d.i || end > len(d.in) || d.in[end-1] != '\x00' { + corrupted() + } + for d.in[d.i] != '\x00' { + kind := d.readByte() + name := d.readCStr() + if d.i >= end { + corrupted() + } + + switch outk { + case reflect.Map: + e := reflect.New(elemType).Elem() + if d.readElemTo(e, kind) { + k := reflect.ValueOf(name) + if convertKey { + k = k.Convert(keyType) + } + out.SetMapIndex(k, e) + } + case reflect.Struct: + if outt == typeRaw { + d.dropElem(kind) + } else { + if info, ok := fieldsMap[name]; ok { + if info.Inline == nil { + d.readElemTo(out.Field(info.Num), kind) + } else { + d.readElemTo(out.FieldByIndex(info.Inline), kind) + } + } else if inlineMap.IsValid() { + if inlineMap.IsNil() { + inlineMap.Set(reflect.MakeMap(inlineMap.Type())) + } + e := reflect.New(elemType).Elem() + if d.readElemTo(e, kind) { + inlineMap.SetMapIndex(reflect.ValueOf(name), e) + } + } else { + d.dropElem(kind) + } + } + case reflect.Slice: + } + + if d.i >= end { + corrupted() + } + } + d.i++ // '\x00' + if d.i != end { + corrupted() + } + d.docType = docType + + if outt == typeRaw { + out.Set(reflect.ValueOf(Raw{0x03, d.in[start:d.i]})) + } +} + +func (d *decoder) readArrayDocTo(out reflect.Value) { + end := int(d.readInt32()) + end += d.i - 4 + if end <= d.i || end > len(d.in) || d.in[end-1] != '\x00' { + corrupted() + } + i := 0 + l := out.Len() + for d.in[d.i] != '\x00' { + if i >= l { + panic("Length mismatch on array field") + } + kind := d.readByte() + for d.i < end && d.in[d.i] != '\x00' { + d.i++ + } + if d.i >= end { + corrupted() + } + d.i++ + d.readElemTo(out.Index(i), kind) + if d.i >= end { + corrupted() + } + i++ + } + if i != l { + panic("Length mismatch on array field") + } + d.i++ // '\x00' + if d.i != end { + corrupted() + } +} + +func (d *decoder) readSliceDoc(t reflect.Type) interface{} { + tmp := make([]reflect.Value, 0, 8) + elemType := t.Elem() + if elemType == typeRawDocElem { + d.dropElem(0x04) + return reflect.Zero(t).Interface() + } + + end := int(d.readInt32()) + end += d.i - 4 + if end <= d.i || end > len(d.in) || d.in[end-1] != '\x00' { + corrupted() + } + for d.in[d.i] != '\x00' { + kind := d.readByte() + for d.i < end && d.in[d.i] != '\x00' { + d.i++ + } + if d.i >= end { + corrupted() + } + d.i++ + e := reflect.New(elemType).Elem() + if d.readElemTo(e, kind) { + tmp = append(tmp, e) + } + if d.i >= end { + corrupted() + } + } + d.i++ // '\x00' + if d.i != end { + corrupted() + } + + n := len(tmp) + slice := reflect.MakeSlice(t, n, n) + for i := 0; i != n; i++ { + slice.Index(i).Set(tmp[i]) + } + return slice.Interface() +} + +var typeSlice = reflect.TypeOf([]interface{}{}) +var typeIface = typeSlice.Elem() + +func (d *decoder) readDocElems(typ reflect.Type) reflect.Value { + docType := d.docType + d.docType = typ + slice := make([]DocElem, 0, 8) + d.readDocWith(func(kind byte, name string) { + e := DocElem{Name: name} + v := reflect.ValueOf(&e.Value) + if d.readElemTo(v.Elem(), kind) { + slice = append(slice, e) + } + }) + slicev := reflect.New(typ).Elem() + slicev.Set(reflect.ValueOf(slice)) + d.docType = docType + return slicev +} + +func (d *decoder) readRawDocElems(typ reflect.Type) reflect.Value { + docType := d.docType + d.docType = typ + slice := make([]RawDocElem, 0, 8) + d.readDocWith(func(kind byte, name string) { + e := RawDocElem{Name: name} + v := reflect.ValueOf(&e.Value) + if d.readElemTo(v.Elem(), kind) { + slice = append(slice, e) + } + }) + slicev := reflect.New(typ).Elem() + slicev.Set(reflect.ValueOf(slice)) + d.docType = docType + return slicev +} + +func (d *decoder) readDocWith(f func(kind byte, name string)) { + end := int(d.readInt32()) + end += d.i - 4 + if end <= d.i || end > len(d.in) || d.in[end-1] != '\x00' { + corrupted() + } + for d.in[d.i] != '\x00' { + kind := d.readByte() + name := d.readCStr() + if d.i >= end { + corrupted() + } + f(kind, name) + if d.i >= end { + corrupted() + } + } + d.i++ // '\x00' + if d.i != end { + corrupted() + } +} + +// -------------------------------------------------------------------------- +// Unmarshaling of individual elements within a document. + +var blackHole = settableValueOf(struct{}{}) + +func (d *decoder) dropElem(kind byte) { + d.readElemTo(blackHole, kind) +} + +// Attempt to decode an element from the document and put it into out. +// If the types are not compatible, the returned ok value will be +// false and out will be unchanged. +func (d *decoder) readElemTo(out reflect.Value, kind byte) (good bool) { + + start := d.i + + if kind == 0x03 { + // Delegate unmarshaling of documents. + outt := out.Type() + outk := out.Kind() + switch outk { + case reflect.Interface, reflect.Ptr, reflect.Struct, reflect.Map: + d.readDocTo(out) + return true + } + if setterStyle(outt) != setterNone { + d.readDocTo(out) + return true + } + if outk == reflect.Slice { + switch outt.Elem() { + case typeDocElem: + out.Set(d.readDocElems(outt)) + case typeRawDocElem: + out.Set(d.readRawDocElems(outt)) + default: + d.readDocTo(blackHole) + } + return true + } + d.readDocTo(blackHole) + return true + } + + var in interface{} + + switch kind { + case 0x01: // Float64 + in = d.readFloat64() + case 0x02: // UTF-8 string + in = d.readStr() + case 0x03: // Document + panic("Can't happen. Handled above.") + case 0x04: // Array + outt := out.Type() + if setterStyle(outt) != setterNone { + // Skip the value so its data is handed to the setter below. + d.dropElem(kind) + break + } + for outt.Kind() == reflect.Ptr { + outt = outt.Elem() + } + switch outt.Kind() { + case reflect.Array: + d.readArrayDocTo(out) + return true + case reflect.Slice: + in = d.readSliceDoc(outt) + default: + in = d.readSliceDoc(typeSlice) + } + case 0x05: // Binary + b := d.readBinary() + if b.Kind == 0x00 || b.Kind == 0x02 { + in = b.Data + } else { + in = b + } + case 0x06: // Undefined (obsolete, but still seen in the wild) + in = Undefined + case 0x07: // ObjectId + in = ObjectId(d.readBytes(12)) + case 0x08: // Bool + in = d.readBool() + case 0x09: // Timestamp + // MongoDB handles timestamps as milliseconds. + i := d.readInt64() + if i == -62135596800000 { + in = time.Time{} // In UTC for convenience. + } else { + in = time.Unix(i/1e3, i%1e3*1e6) + } + case 0x0A: // Nil + in = nil + case 0x0B: // RegEx + in = d.readRegEx() + case 0x0C: + in = DBPointer{Namespace: d.readStr(), Id: ObjectId(d.readBytes(12))} + case 0x0D: // JavaScript without scope + in = JavaScript{Code: d.readStr()} + case 0x0E: // Symbol + in = Symbol(d.readStr()) + case 0x0F: // JavaScript with scope + d.i += 4 // Skip length + js := JavaScript{d.readStr(), make(M)} + d.readDocTo(reflect.ValueOf(js.Scope)) + in = js + case 0x10: // Int32 + in = int(d.readInt32()) + case 0x11: // Mongo-specific timestamp + in = MongoTimestamp(d.readInt64()) + case 0x12: // Int64 + in = d.readInt64() + case 0x7F: // Max key + in = MaxKey + case 0xFF: // Min key + in = MinKey + default: + panic(fmt.Sprintf("Unknown element kind (0x%02X)", kind)) + } + + outt := out.Type() + + if outt == typeRaw { + out.Set(reflect.ValueOf(Raw{kind, d.in[start:d.i]})) + return true + } + + if setter := getSetter(outt, out); setter != nil { + err := setter.SetBSON(Raw{kind, d.in[start:d.i]}) + if err == SetZero { + out.Set(reflect.Zero(outt)) + return true + } + if err == nil { + return true + } + if _, ok := err.(*TypeError); !ok { + panic(err) + } + return false + } + + if in == nil { + out.Set(reflect.Zero(outt)) + return true + } + + outk := outt.Kind() + + // Dereference and initialize pointer if necessary. + first := true + for outk == reflect.Ptr { + if !out.IsNil() { + out = out.Elem() + } else { + elem := reflect.New(outt.Elem()) + if first { + // Only set if value is compatible. + first = false + defer func(out, elem reflect.Value) { + if good { + out.Set(elem) + } + }(out, elem) + } else { + out.Set(elem) + } + out = elem + } + outt = out.Type() + outk = outt.Kind() + } + + inv := reflect.ValueOf(in) + if outt == inv.Type() { + out.Set(inv) + return true + } + + switch outk { + case reflect.Interface: + out.Set(inv) + return true + case reflect.String: + switch inv.Kind() { + case reflect.String: + out.SetString(inv.String()) + return true + case reflect.Slice: + if b, ok := in.([]byte); ok { + out.SetString(string(b)) + return true + } + case reflect.Int, reflect.Int64: + if outt == typeJSONNumber { + out.SetString(strconv.FormatInt(inv.Int(), 10)) + return true + } + case reflect.Float64: + if outt == typeJSONNumber { + out.SetString(strconv.FormatFloat(inv.Float(), 'f', -1, 64)) + return true + } + } + case reflect.Slice, reflect.Array: + // Remember, array (0x04) slices are built with the correct + // element type. If we are here, must be a cross BSON kind + // conversion (e.g. 0x05 unmarshalling on string). + if outt.Elem().Kind() != reflect.Uint8 { + break + } + switch inv.Kind() { + case reflect.String: + slice := []byte(inv.String()) + out.Set(reflect.ValueOf(slice)) + return true + case reflect.Slice: + switch outt.Kind() { + case reflect.Array: + reflect.Copy(out, inv) + case reflect.Slice: + out.SetBytes(inv.Bytes()) + } + return true + } + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + switch inv.Kind() { + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + out.SetInt(inv.Int()) + return true + case reflect.Float32, reflect.Float64: + out.SetInt(int64(inv.Float())) + return true + case reflect.Bool: + if inv.Bool() { + out.SetInt(1) + } else { + out.SetInt(0) + } + return true + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + panic("can't happen: no uint types in BSON (!?)") + } + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + switch inv.Kind() { + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + out.SetUint(uint64(inv.Int())) + return true + case reflect.Float32, reflect.Float64: + out.SetUint(uint64(inv.Float())) + return true + case reflect.Bool: + if inv.Bool() { + out.SetUint(1) + } else { + out.SetUint(0) + } + return true + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + panic("Can't happen. No uint types in BSON.") + } + case reflect.Float32, reflect.Float64: + switch inv.Kind() { + case reflect.Float32, reflect.Float64: + out.SetFloat(inv.Float()) + return true + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + out.SetFloat(float64(inv.Int())) + return true + case reflect.Bool: + if inv.Bool() { + out.SetFloat(1) + } else { + out.SetFloat(0) + } + return true + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + panic("Can't happen. No uint types in BSON?") + } + case reflect.Bool: + switch inv.Kind() { + case reflect.Bool: + out.SetBool(inv.Bool()) + return true + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + out.SetBool(inv.Int() != 0) + return true + case reflect.Float32, reflect.Float64: + out.SetBool(inv.Float() != 0) + return true + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + panic("Can't happen. No uint types in BSON?") + } + case reflect.Struct: + if outt == typeURL && inv.Kind() == reflect.String { + u, err := url.Parse(inv.String()) + if err != nil { + panic(err) + } + out.Set(reflect.ValueOf(u).Elem()) + return true + } + if outt == typeBinary { + if b, ok := in.([]byte); ok { + out.Set(reflect.ValueOf(Binary{Data: b})) + return true + } + } + } + + return false +} + +// -------------------------------------------------------------------------- +// Parsers of basic types. + +func (d *decoder) readRegEx() RegEx { + re := RegEx{} + re.Pattern = d.readCStr() + re.Options = d.readCStr() + return re +} + +func (d *decoder) readBinary() Binary { + l := d.readInt32() + b := Binary{} + b.Kind = d.readByte() + b.Data = d.readBytes(l) + if b.Kind == 0x02 && len(b.Data) >= 4 { + // Weird obsolete format with redundant length. + b.Data = b.Data[4:] + } + return b +} + +func (d *decoder) readStr() string { + l := d.readInt32() + b := d.readBytes(l - 1) + if d.readByte() != '\x00' { + corrupted() + } + return string(b) +} + +func (d *decoder) readCStr() string { + start := d.i + end := start + l := len(d.in) + for ; end != l; end++ { + if d.in[end] == '\x00' { + break + } + } + d.i = end + 1 + if d.i > l { + corrupted() + } + return string(d.in[start:end]) +} + +func (d *decoder) readBool() bool { + b := d.readByte() + if b == 0 { + return false + } + if b == 1 { + return true + } + panic(fmt.Sprintf("encoded boolean must be 1 or 0, found %d", b)) +} + +func (d *decoder) readFloat64() float64 { + return math.Float64frombits(uint64(d.readInt64())) +} + +func (d *decoder) readInt32() int32 { + b := d.readBytes(4) + return int32((uint32(b[0]) << 0) | + (uint32(b[1]) << 8) | + (uint32(b[2]) << 16) | + (uint32(b[3]) << 24)) +} + +func (d *decoder) readInt64() int64 { + b := d.readBytes(8) + return int64((uint64(b[0]) << 0) | + (uint64(b[1]) << 8) | + (uint64(b[2]) << 16) | + (uint64(b[3]) << 24) | + (uint64(b[4]) << 32) | + (uint64(b[5]) << 40) | + (uint64(b[6]) << 48) | + (uint64(b[7]) << 56)) +} + +func (d *decoder) readByte() byte { + i := d.i + d.i++ + if d.i > len(d.in) { + corrupted() + } + return d.in[i] +} + +func (d *decoder) readBytes(length int32) []byte { + if length < 0 { + corrupted() + } + start := d.i + d.i += int(length) + if d.i < start || d.i > len(d.in) { + corrupted() + } + return d.in[start : start+int(length)] +} |