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Diffstat (limited to 'vendor/github.com/golang/protobuf/proto/properties.go')
| -rw-r--r-- | vendor/github.com/golang/protobuf/proto/properties.go | 544 |
1 files changed, 544 insertions, 0 deletions
diff --git a/vendor/github.com/golang/protobuf/proto/properties.go b/vendor/github.com/golang/protobuf/proto/properties.go new file mode 100644 index 00000000..50b99b83 --- /dev/null +++ b/vendor/github.com/golang/protobuf/proto/properties.go @@ -0,0 +1,544 @@ +// Go support for Protocol Buffers - Google's data interchange format +// +// Copyright 2010 The Go Authors. All rights reserved. +// https://github.com/golang/protobuf +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * 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. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// 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. + +package proto + +/* + * Routines for encoding data into the wire format for protocol buffers. + */ + +import ( + "fmt" + "log" + "os" + "reflect" + "sort" + "strconv" + "strings" + "sync" +) + +const debug bool = false + +// Constants that identify the encoding of a value on the wire. +const ( + WireVarint = 0 + WireFixed64 = 1 + WireBytes = 2 + WireStartGroup = 3 + WireEndGroup = 4 + WireFixed32 = 5 +) + +// tagMap is an optimization over map[int]int for typical protocol buffer +// use-cases. Encoded protocol buffers are often in tag order with small tag +// numbers. +type tagMap struct { + fastTags []int + slowTags map[int]int +} + +// tagMapFastLimit is the upper bound on the tag number that will be stored in +// the tagMap slice rather than its map. +const tagMapFastLimit = 1024 + +func (p *tagMap) get(t int) (int, bool) { + if t > 0 && t < tagMapFastLimit { + if t >= len(p.fastTags) { + return 0, false + } + fi := p.fastTags[t] + return fi, fi >= 0 + } + fi, ok := p.slowTags[t] + return fi, ok +} + +func (p *tagMap) put(t int, fi int) { + if t > 0 && t < tagMapFastLimit { + for len(p.fastTags) < t+1 { + p.fastTags = append(p.fastTags, -1) + } + p.fastTags[t] = fi + return + } + if p.slowTags == nil { + p.slowTags = make(map[int]int) + } + p.slowTags[t] = fi +} + +// StructProperties represents properties for all the fields of a struct. +// decoderTags and decoderOrigNames should only be used by the decoder. +type StructProperties struct { + Prop []*Properties // properties for each field + reqCount int // required count + decoderTags tagMap // map from proto tag to struct field number + decoderOrigNames map[string]int // map from original name to struct field number + order []int // list of struct field numbers in tag order + + // OneofTypes contains information about the oneof fields in this message. + // It is keyed by the original name of a field. + OneofTypes map[string]*OneofProperties +} + +// OneofProperties represents information about a specific field in a oneof. +type OneofProperties struct { + Type reflect.Type // pointer to generated struct type for this oneof field + Field int // struct field number of the containing oneof in the message + Prop *Properties +} + +// Implement the sorting interface so we can sort the fields in tag order, as recommended by the spec. +// See encode.go, (*Buffer).enc_struct. + +func (sp *StructProperties) Len() int { return len(sp.order) } +func (sp *StructProperties) Less(i, j int) bool { + return sp.Prop[sp.order[i]].Tag < sp.Prop[sp.order[j]].Tag +} +func (sp *StructProperties) Swap(i, j int) { sp.order[i], sp.order[j] = sp.order[j], sp.order[i] } + +// Properties represents the protocol-specific behavior of a single struct field. +type Properties struct { + Name string // name of the field, for error messages + OrigName string // original name before protocol compiler (always set) + JSONName string // name to use for JSON; determined by protoc + Wire string + WireType int + Tag int + Required bool + Optional bool + Repeated bool + Packed bool // relevant for repeated primitives only + Enum string // set for enum types only + proto3 bool // whether this is known to be a proto3 field + oneof bool // whether this is a oneof field + + Default string // default value + HasDefault bool // whether an explicit default was provided + + stype reflect.Type // set for struct types only + sprop *StructProperties // set for struct types only + + mtype reflect.Type // set for map types only + MapKeyProp *Properties // set for map types only + MapValProp *Properties // set for map types only +} + +// String formats the properties in the protobuf struct field tag style. +func (p *Properties) String() string { + s := p.Wire + s += "," + s += strconv.Itoa(p.Tag) + if p.Required { + s += ",req" + } + if p.Optional { + s += ",opt" + } + if p.Repeated { + s += ",rep" + } + if p.Packed { + s += ",packed" + } + s += ",name=" + p.OrigName + if p.JSONName != p.OrigName { + s += ",json=" + p.JSONName + } + if p.proto3 { + s += ",proto3" + } + if p.oneof { + s += ",oneof" + } + if len(p.Enum) > 0 { + s += ",enum=" + p.Enum + } + if p.HasDefault { + s += ",def=" + p.Default + } + return s +} + +// Parse populates p by parsing a string in the protobuf struct field tag style. +func (p *Properties) Parse(s string) { + // "bytes,49,opt,name=foo,def=hello!" + fields := strings.Split(s, ",") // breaks def=, but handled below. + if len(fields) < 2 { + fmt.Fprintf(os.Stderr, "proto: tag has too few fields: %q\n", s) + return + } + + p.Wire = fields[0] + switch p.Wire { + case "varint": + p.WireType = WireVarint + case "fixed32": + p.WireType = WireFixed32 + case "fixed64": + p.WireType = WireFixed64 + case "zigzag32": + p.WireType = WireVarint + case "zigzag64": + p.WireType = WireVarint + case "bytes", "group": + p.WireType = WireBytes + // no numeric converter for non-numeric types + default: + fmt.Fprintf(os.Stderr, "proto: tag has unknown wire type: %q\n", s) + return + } + + var err error + p.Tag, err = strconv.Atoi(fields[1]) + if err != nil { + return + } + +outer: + for i := 2; i < len(fields); i++ { + f := fields[i] + switch { + case f == "req": + p.Required = true + case f == "opt": + p.Optional = true + case f == "rep": + p.Repeated = true + case f == "packed": + p.Packed = true + case strings.HasPrefix(f, "name="): + p.OrigName = f[5:] + case strings.HasPrefix(f, "json="): + p.JSONName = f[5:] + case strings.HasPrefix(f, "enum="): + p.Enum = f[5:] + case f == "proto3": + p.proto3 = true + case f == "oneof": + p.oneof = true + case strings.HasPrefix(f, "def="): + p.HasDefault = true + p.Default = f[4:] // rest of string + if i+1 < len(fields) { + // Commas aren't escaped, and def is always last. + p.Default += "," + strings.Join(fields[i+1:], ",") + break outer + } + } + } +} + +var protoMessageType = reflect.TypeOf((*Message)(nil)).Elem() + +// setFieldProps initializes the field properties for submessages and maps. +func (p *Properties) setFieldProps(typ reflect.Type, f *reflect.StructField, lockGetProp bool) { + switch t1 := typ; t1.Kind() { + case reflect.Ptr: + if t1.Elem().Kind() == reflect.Struct { + p.stype = t1.Elem() + } + + case reflect.Slice: + if t2 := t1.Elem(); t2.Kind() == reflect.Ptr && t2.Elem().Kind() == reflect.Struct { + p.stype = t2.Elem() + } + + case reflect.Map: + p.mtype = t1 + p.MapKeyProp = &Properties{} + p.MapKeyProp.init(reflect.PtrTo(p.mtype.Key()), "Key", f.Tag.Get("protobuf_key"), nil, lockGetProp) + p.MapValProp = &Properties{} + vtype := p.mtype.Elem() + if vtype.Kind() != reflect.Ptr && vtype.Kind() != reflect.Slice { + // The value type is not a message (*T) or bytes ([]byte), + // so we need encoders for the pointer to this type. + vtype = reflect.PtrTo(vtype) + } + p.MapValProp.init(vtype, "Value", f.Tag.Get("protobuf_val"), nil, lockGetProp) + } + + if p.stype != nil { + if lockGetProp { + p.sprop = GetProperties(p.stype) + } else { + p.sprop = getPropertiesLocked(p.stype) + } + } +} + +var ( + marshalerType = reflect.TypeOf((*Marshaler)(nil)).Elem() +) + +// Init populates the properties from a protocol buffer struct tag. +func (p *Properties) Init(typ reflect.Type, name, tag string, f *reflect.StructField) { + p.init(typ, name, tag, f, true) +} + +func (p *Properties) init(typ reflect.Type, name, tag string, f *reflect.StructField, lockGetProp bool) { + // "bytes,49,opt,def=hello!" + p.Name = name + p.OrigName = name + if tag == "" { + return + } + p.Parse(tag) + p.setFieldProps(typ, f, lockGetProp) +} + +var ( + propertiesMu sync.RWMutex + propertiesMap = make(map[reflect.Type]*StructProperties) +) + +// GetProperties returns the list of properties for the type represented by t. +// t must represent a generated struct type of a protocol message. +func GetProperties(t reflect.Type) *StructProperties { + if t.Kind() != reflect.Struct { + panic("proto: type must have kind struct") + } + + // Most calls to GetProperties in a long-running program will be + // retrieving details for types we have seen before. + propertiesMu.RLock() + sprop, ok := propertiesMap[t] + propertiesMu.RUnlock() + if ok { + if collectStats { + stats.Chit++ + } + return sprop + } + + propertiesMu.Lock() + sprop = getPropertiesLocked(t) + propertiesMu.Unlock() + return sprop +} + +// getPropertiesLocked requires that propertiesMu is held. +func getPropertiesLocked(t reflect.Type) *StructProperties { + if prop, ok := propertiesMap[t]; ok { + if collectStats { + stats.Chit++ + } + return prop + } + if collectStats { + stats.Cmiss++ + } + + prop := new(StructProperties) + // in case of recursive protos, fill this in now. + propertiesMap[t] = prop + + // build properties + prop.Prop = make([]*Properties, t.NumField()) + prop.order = make([]int, t.NumField()) + + for i := 0; i < t.NumField(); i++ { + f := t.Field(i) + p := new(Properties) + name := f.Name + p.init(f.Type, name, f.Tag.Get("protobuf"), &f, false) + + oneof := f.Tag.Get("protobuf_oneof") // special case + if oneof != "" { + // Oneof fields don't use the traditional protobuf tag. + p.OrigName = oneof + } + prop.Prop[i] = p + prop.order[i] = i + if debug { + print(i, " ", f.Name, " ", t.String(), " ") + if p.Tag > 0 { + print(p.String()) + } + print("\n") + } + } + + // Re-order prop.order. + sort.Sort(prop) + + type oneofMessage interface { + XXX_OneofFuncs() (func(Message, *Buffer) error, func(Message, int, int, *Buffer) (bool, error), func(Message) int, []interface{}) + } + if om, ok := reflect.Zero(reflect.PtrTo(t)).Interface().(oneofMessage); ok { + var oots []interface{} + _, _, _, oots = om.XXX_OneofFuncs() + + // Interpret oneof metadata. + prop.OneofTypes = make(map[string]*OneofProperties) + for _, oot := range oots { + oop := &OneofProperties{ + Type: reflect.ValueOf(oot).Type(), // *T + Prop: new(Properties), + } + sft := oop.Type.Elem().Field(0) + oop.Prop.Name = sft.Name + oop.Prop.Parse(sft.Tag.Get("protobuf")) + // There will be exactly one interface field that + // this new value is assignable to. + for i := 0; i < t.NumField(); i++ { + f := t.Field(i) + if f.Type.Kind() != reflect.Interface { + continue + } + if !oop.Type.AssignableTo(f.Type) { + continue + } + oop.Field = i + break + } + prop.OneofTypes[oop.Prop.OrigName] = oop + } + } + + // build required counts + // build tags + reqCount := 0 + prop.decoderOrigNames = make(map[string]int) + for i, p := range prop.Prop { + if strings.HasPrefix(p.Name, "XXX_") { + // Internal fields should not appear in tags/origNames maps. + // They are handled specially when encoding and decoding. + continue + } + if p.Required { + reqCount++ + } + prop.decoderTags.put(p.Tag, i) + prop.decoderOrigNames[p.OrigName] = i + } + prop.reqCount = reqCount + + return prop +} + +// A global registry of enum types. +// The generated code will register the generated maps by calling RegisterEnum. + +var enumValueMaps = make(map[string]map[string]int32) + +// RegisterEnum is called from the generated code to install the enum descriptor +// maps into the global table to aid parsing text format protocol buffers. +func RegisterEnum(typeName string, unusedNameMap map[int32]string, valueMap map[string]int32) { + if _, ok := enumValueMaps[typeName]; ok { + panic("proto: duplicate enum registered: " + typeName) + } + enumValueMaps[typeName] = valueMap +} + +// EnumValueMap returns the mapping from names to integers of the +// enum type enumType, or a nil if not found. +func EnumValueMap(enumType string) map[string]int32 { + return enumValueMaps[enumType] +} + +// A registry of all linked message types. +// The string is a fully-qualified proto name ("pkg.Message"). +var ( + protoTypedNils = make(map[string]Message) // a map from proto names to typed nil pointers + protoMapTypes = make(map[string]reflect.Type) // a map from proto names to map types + revProtoTypes = make(map[reflect.Type]string) +) + +// RegisterType is called from generated code and maps from the fully qualified +// proto name to the type (pointer to struct) of the protocol buffer. +func RegisterType(x Message, name string) { + if _, ok := protoTypedNils[name]; ok { + // TODO: Some day, make this a panic. + log.Printf("proto: duplicate proto type registered: %s", name) + return + } + t := reflect.TypeOf(x) + if v := reflect.ValueOf(x); v.Kind() == reflect.Ptr && v.Pointer() == 0 { + // Generated code always calls RegisterType with nil x. + // This check is just for extra safety. + protoTypedNils[name] = x + } else { + protoTypedNils[name] = reflect.Zero(t).Interface().(Message) + } + revProtoTypes[t] = name +} + +// RegisterMapType is called from generated code and maps from the fully qualified +// proto name to the native map type of the proto map definition. +func RegisterMapType(x interface{}, name string) { + if reflect.TypeOf(x).Kind() != reflect.Map { + panic(fmt.Sprintf("RegisterMapType(%T, %q); want map", x, name)) + } + if _, ok := protoMapTypes[name]; ok { + log.Printf("proto: duplicate proto type registered: %s", name) + return + } + t := reflect.TypeOf(x) + protoMapTypes[name] = t + revProtoTypes[t] = name +} + +// MessageName returns the fully-qualified proto name for the given message type. +func MessageName(x Message) string { + type xname interface { + XXX_MessageName() string + } + if m, ok := x.(xname); ok { + return m.XXX_MessageName() + } + return revProtoTypes[reflect.TypeOf(x)] +} + +// MessageType returns the message type (pointer to struct) for a named message. +// The type is not guaranteed to implement proto.Message if the name refers to a +// map entry. +func MessageType(name string) reflect.Type { + if t, ok := protoTypedNils[name]; ok { + return reflect.TypeOf(t) + } + return protoMapTypes[name] +} + +// A registry of all linked proto files. +var ( + protoFiles = make(map[string][]byte) // file name => fileDescriptor +) + +// RegisterFile is called from generated code and maps from the +// full file name of a .proto file to its compressed FileDescriptorProto. +func RegisterFile(filename string, fileDescriptor []byte) { + protoFiles[filename] = fileDescriptor +} + +// FileDescriptor returns the compressed FileDescriptorProto for a .proto file. +func FileDescriptor(filename string) []byte { return protoFiles[filename] } |