pw::protobuf::CallbackDecoder Class Reference

Overview

A protobuf decoder that iterates over an encoded protobuf, calling a handler for each field it encounters.

class FooProtoHandler : public DecodeHandler {
 public:
  Status ProcessField(CallbackDecoder& decoder,
                      uint32_t field_number) override {
    switch (field_number) {
      case FooFields::kBar:
        if (!decoder.ReadSint32(&bar).ok()) {
          bar = 0;
        }
        break;
      case FooFields::kBaz:
        if (!decoder.ReadUint32(&baz).ok()) {
          baz = 0;
        }
        break;
    }
 
    return OkStatus();
  }
 
  int bar;
  unsigned int baz;
};
 
void DecodeFooProto(span<std::byte> raw_proto) {
  Decoder decoder;
  FooProtoHandler handler;
 
  decoder.set_handler(&handler);
  if (!decoder.Decode(raw_proto).ok()) {
    LOG_FATAL("Invalid foo message!");
  }
 
  LOG_INFO("Read Foo proto message; bar: %d baz: %u",
           handler.bar, handler.baz);
}

Public Member Functions
	CallbackDecoder (const CallbackDecoder &other)=delete
CallbackDecoder &	operator= (const CallbackDecoder &other)=delete
void	set_handler (DecodeHandler *handler)
Status	Decode (span< const std::byte > proto)
Status	ReadInt32 (int32_t *out)
Status	ReadUint32 (uint32_t *out)
Status	ReadInt64 (int64_t *out)
Status	ReadUint64 (uint64_t *out)
Status	ReadSint32 (int32_t *out)
Status	ReadSint64 (int64_t *out)
Status	ReadBool (bool *out)
Status	ReadFixed32 (uint32_t *out)
Status	ReadFixed64 (uint64_t *out)
Status	ReadSfixed32 (int32_t *out)
Status	ReadSfixed64 (int64_t *out)
Status	ReadFloat (float *out)
Status	ReadDouble (double *out)
Status	ReadString (std::string_view *out)
Status	ReadBytes (span< const std::byte > *out)
bool	cancelled () const

Member Function Documentation

Decode()

Status pw::protobuf::CallbackDecoder::Decode

(

span< const std::byte >

proto

)

Decodes the specified protobuf data.

The registered handler's ProcessField function is called on each field found in the data.

Parameters

[in]

proto

Span containing the serialized protobuf data.

Returns

Status resulting from the decoding operation or handler return.

ReadBool()

Status pw::protobuf::CallbackDecoder::ReadBool ( bool *  out )

inline

Reads a proto bool value from the current cursor.

Parameters

[out]

out

Pointer to store the read bool value.

ReadBytes()

Status pw::protobuf::CallbackDecoder::ReadBytes ( span< const std::byte > *  out )

inline

Reads a proto bytes value from the current cursor as a view.

Note

The raw protobuf data must outlive out. If the bytes field is invalid, out is not modified.

Parameters

[out]

out

Pointer to store the byte span view (span<const std::byte>).

ReadDouble()

Status pw::protobuf::CallbackDecoder::ReadDouble ( double *  out )

inline

Reads a proto double value from the current cursor.

Parameters

[out]

out

Pointer to store the read double value.

ReadFixed32()

Status pw::protobuf::CallbackDecoder::ReadFixed32 ( uint32_t *  out )

inline

Reads a proto fixed32 value from the current cursor.

Parameters

[out]

out

Pointer to store the read fixed32 value.

ReadFixed64()

Status pw::protobuf::CallbackDecoder::ReadFixed64 ( uint64_t *  out )

inline

Reads a proto fixed64 value from the current cursor.

Parameters

[out]

out

Pointer to store the read fixed64 value.

ReadFloat()

Status pw::protobuf::CallbackDecoder::ReadFloat ( float *  out )

inline

Reads a proto float value from the current cursor.

Parameters

[out]

out

Pointer to store the read float value.

ReadInt32()

Status pw::protobuf::CallbackDecoder::ReadInt32 ( int32_t *  out )

inline

Reads a proto int32 value from the current cursor.

Parameters

[out]

out

Pointer to store the read int32 value.

ReadInt64()

Status pw::protobuf::CallbackDecoder::ReadInt64 ( int64_t *  out )

inline

Reads a proto int64 value from the current cursor.

Parameters

[out]

out

Pointer to store the read int64 value.

ReadSfixed32()

Status pw::protobuf::CallbackDecoder::ReadSfixed32 ( int32_t *  out )

inline

Reads a proto sfixed32 value from the current cursor.

Parameters

[out]

out

Pointer to store the read sfixed32 value.

ReadSfixed64()

Status pw::protobuf::CallbackDecoder::ReadSfixed64 ( int64_t *  out )

inline

Reads a proto sfixed64 value from the current cursor.

Parameters

[out]

out

Pointer to store the read sfixed64 value.

ReadSint32()

Status pw::protobuf::CallbackDecoder::ReadSint32 ( int32_t *  out )

inline

Reads a proto sint32 value from the current cursor.

Parameters

[out]

out

Pointer to store the read sint32 value.

ReadSint64()

Status pw::protobuf::CallbackDecoder::ReadSint64 ( int64_t *  out )

inline

Reads a proto sint64 value from the current cursor.

Parameters

[out]

out

Pointer to store the read sint64 value.

ReadString()

Status pw::protobuf::CallbackDecoder::ReadString ( std::string_view *  out )

inline

Reads a proto string value from the current cursor as a view.

Note

The raw protobuf data must outlive out. If the string field is invalid, out is not modified.

Parameters

[out]

out

Pointer to store the std::string_view.

ReadUint32()

Status pw::protobuf::CallbackDecoder::ReadUint32 ( uint32_t *  out )

inline

Reads a proto uint32 value from the current cursor.

Parameters

[out]

out

Pointer to store the read uint32 value.

ReadUint64()

Status pw::protobuf::CallbackDecoder::ReadUint64 ( uint64_t *  out )

inline

Reads a proto uint64 value from the current cursor.

Parameters

[out]

out

Pointer to store the read uint64 value.

set_handler()

void pw::protobuf::CallbackDecoder::set_handler ( DecodeHandler *  handler )

inline

Sets the DecodeHandler to process encountered fields.

Parameters

[in]

handler

Pointer to the decode handler instance.

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The documentation for this class was generated from the following file:

• pw_protobuf/public/pw_protobuf/decoder.h