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Grijjy.ProtocolBuffers.pas
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Grijjy.ProtocolBuffers.pas
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unit Grijjy.ProtocolBuffers;
(*<Google Protocol Buffers for Delphi.
This unit contains declarations for serializing attributed Delphi records
in Protocol Buffer format.
It does @bold(not) use the Google Protocol Buffers framework. Instead, it uses
a custom framework, but serializes in a Protocol Buffers compatible bitstream.
@bold(About Protocol Buffers)
Protocol Buffers is both a framework and a bitstream specification:
https://developers.google.com/protocol-buffers/
It is used to serialize messages in an efficient binary format. A message is
a collection of fields, where each field is uniquely identified with an
integer Tag. Fields can be of various simple data types, including integers,
enums, strings, booleans and strings, as well as compound data types such as
nested messages, repeated messages (arrays) and binary data.
@bold(Delphi Implementation)
This Delphi implementation uses attributed records to define messages. These
are regular Delphi records, but fields that are decorated with the [Serialize]
attribute can be serialized. For example:
<source>
type
TPhoneType = (Mobile, Home, Work);
type
TPhoneNumber = record
public
[Serialize(1)] Number: String;
[Serialize(2)] PhoneType: TPhoneType;
public
procedure Initialize;
end;
type
TPerson = record
public
[Serialize(1)] Name: String;
[Serialize(2)] Id: Integer;
[Serialize(3)] Email: String;
[Serialize(4)] MainPhone: TPhoneNumber;
[Serialize(5)] OtherPhones: TArray<TPhoneNumber>;
public
procedure Initialize;
end;
</source>
Each serializable field must be decorated with a [Serialize] attribute with a
single parameter containing the Tag for that field. Tags @bold(must) be unique
within the record, but you can use the same tag in different records or in
nested records. When a record contains duplicate tags, an exception will be
raised when the record is (de)serialized.
Tags start at 1 and must be positive. You should reserve tags 1-15 for the
most common fields, since these tags are stored most efficiently (using 1
byte). Tags 16-2047 are stored in 2 bytes, and other tags take more bytes.
Records are serialized in an extensible way. You can add, delete and reorder
fields without breaking compatibility with older bitstreams. However, you
should never change the tag or data type of a field.
@bold(Supported Data Types)
You can use a wide variety of Delphi data types for your serializable fields:
* UInt8 (Byte), UInt16 (Word), UInt32 (Longword/Cardinal), UInt64
* Int8 (Shortint), Int16 (Smallint), Int32 (Longint/Integer), Int64
* Single, Double
* Boolean
* Enumerated types, @bold(as long as) the type does @bold(not) contain any
explicitly assigned values (Delphi does not provide RTTI for these)
* Records (that is, your field can be of another record type)
* Strings (of type UnicodeString)
* TBytes (for raw binary data)
* 1-dimensional dynamic arrays (TArray<>) of the types described above,
Tech note: all arrays of primitive numeric types (integers, floats and enums)
are stored in "packed" format, which is supported since Protocol Buffers
version 2.1.0. This is a more efficient format that doesn't repeat the tag for
each element. All other array types are stored unpacked (where the tag is
repeated for each element).
The integer data types are stored in an efficient VarInt format. This means
that smaller values are stored in less bytes than larger values. 32-bit
integer types are stored in 1-5 bytes, and 64-bit integer types are stored in
1-10 bytes. Sometimes, you can have integer data that contains random values
across the entire 32-bit or 64-bit range. In those cases, it is more efficient
to store these integers as fixed 32-bit or 64-bit values. You can do this
by declaring the field as one of 4 fixed integer types:
* FixedInt32, FixedUInt32, FixedInt64, FixedUInt64
All other data types can @bold(not) be used for serializable fields. An
exception will be raised when an unsupported data type is encountered.
However, you can still use these types for regular (non-serializable) fields.
In particular, the following types are @bold(not) supported:
* Extended, Comp, Currency
* Class, Object, Interface
* Enumerated types with explicitly assigned values
* AnsiString, RawByteString, UCS4String etc.
* Static arrays
* Multi-dimensional dynamic arrays
@bold(Using the (de)serializer)
Serializing is very easy. You just fill your record with the values you want
to serialize and call:
<source>
TgoProtocolBuffer.Serialize<TPerson>(MyPerson, 'Person.dat');
</source>
This is a generic method with a type parameter that must match the type of
record you are serializing.
Since Delphi is able to infer the generic type from the first parameter, you
can also write this a little bit shorter:
<source>
TgoProtocolBuffer.Serialize(MyPerson, 'Person.dat');
</source>
You can serialize to a file, stream or TBytes array.
Deserializing is equally simple:
<source>
TgoProtocolBuffer.Deserialize(MyPerson, 'Person.dat');
</source>
Because all fields in a record are optional, some fields may not be in the
stream. To prevent the record from having unitialized fields after
deserialization, the record is cleared before it is deserialized (that is, all
fields are set to 0 or nil).
You can also provide your own means of initializing the record with default
values. To do that, you have to add a parameterless Initialize procedure to
your record. Then, the deserialization process will call that routine after
clearing the record (so it will still clear any fields you don't initialize
yourself). *)
{$INCLUDE 'Grijjy.inc'}
interface
uses
System.Classes,
System.SysUtils,
System.TypInfo,
System.SyncObjs,
System.Rtti,
System.Generics.Collections,
Grijjy.SysUtils;
type
{ A 32-bit unsigned integer that is always serialized using 4 bytes. }
FixedUInt32 = type UInt32;
{ A 32-bit signed integer that is always serialized using 4 bytes. }
FixedInt32 = type Int32;
{ A 64-bit unsigned integer that is always serialized using 8 bytes. }
FixedUInt64 = type UInt64;
{ A 64-bit signed integer that is always serialized using 8 bytes. }
FixedInt64 = type Int64;
type
{ Valid range of field tags }
TgoSerializationTag = 1..536870911;
type
{ Exception type that is raise when an error occurs during (de)serialization }
EgoSerializationError = class(Exception)
end;
type
{ A Delphi attribute you use to decorate record fields that need to be
serialized. }
SerializeAttribute = class(TCustomAttribute)
{$REGION 'Internal Declarations'}
private
FTag: TgoSerializationTag;
{$ENDREGION 'Internal Declarations'}
public
{ Attribute constructor }
constructor Create(const ATag: TgoSerializationTag);
{ The tag that is associated with the field to which this attribute is
attached. }
property Tag: TgoSerializationTag read FTag;
end;
type
{ Static class used for (de)serializing records in Protocol Buffer format }
TgoProtocolBuffer = class
{$REGION 'Internal Declarations'}
private
type
TWriter = class(TgoByteBuffer)
public
procedure WriteVarUInt(const AValue: Cardinal);
procedure WriteVarInt(const AValue: Integer); inline;
procedure WriteVarUInt64(const AValue: UInt64);
procedure WriteVarInt64(const AValue: Int64); inline;
end;
type
TReader = class
private
FBuffer: PByte;
FSize: Integer;
FIndex: Integer;
public
constructor Create(const ABuffer: Pointer; const ASize: Integer);
function HasData: Boolean; inline;
procedure Skip(const ASize: Integer); inline;
procedure ReadBytes(out AData; const ASize: Integer);
function ReadByte: Byte; inline;
function ReadVarUInt: Cardinal;
function ReadVarInt: Integer;
function ReadVarUInt64: UInt64;
function ReadVarInt64: Int64;
function PeekVarUInt(out ASize: Integer): Cardinal;
property Index: Integer read FIndex;
end;
type
TInitializeProc = procedure(Self: Pointer);
TSerializeProc = procedure(const AWriter: TWriter; const ARecord: PByte;
const ATag, AOffset: Integer; const AParam: TObject);
TDeserializeProc = procedure(const AReader: TReader; const ARecord: PByte;
const ATag, AOffset: Integer; const AParam: TObject);
type
TFieldTypeInfo = class
strict private
FTag: Integer;
FOffset: Integer;
FSerializeProc: TSerializeProc;
FDeserializeProc: TDeserializeProc;
FParam: TObject;
public
constructor Create(const ATag, AOffset: Integer;
const ASerializeProc: TSerializeProc;
const ADeserializeProc: TDeserializeProc; const AParam: TObject);
property Tag: Integer read FTag;
property Offset: Integer read FOffset;
property SerializeProc: TSerializeProc read FSerializeProc;
property DeserializeProc: TDeserializeProc read FDeserializeProc;
property Param: TObject read FParam;
end;
type
TBaseTypeInfo = class
strict private
FSize: Integer;
FTypeInfo: PTypeInfo;
public
constructor Create(const ATypeInfo: PTypeInfo; const ASize: Integer);
property Size: Integer read FSize;
property TypeInfo: PTypeInfo read FTypeInfo;
end;
type
TRecordTypeInfo = class(TBaseTypeInfo)
strict private
FFields: TArray<TFieldTypeInfo>;
FInitProc: TInitializeProc;
public
constructor Create(const ATypeInfo: PTypeInfo; const ASize: Integer;
const AInitProc: TInitializeProc; const AFields: TArray<TFieldTypeInfo>);
destructor Destroy; override;
procedure Serialize(const AWriter: TWriter; const ARecord: Pointer);
procedure Deserialize(const AReader: TReader; const ARecord: Pointer);
property InitProc: TInitializeProc read FInitProc;
end;
type
TArrayTypeInfo = class(TBaseTypeInfo)
strict private
FElementType: PTypeInfo;
FElementSize: Integer;
FElementInfo: TBaseTypeInfo;
FElementSerializeProc: TSerializeProc;
FElementDeserializeProc: TDeserializeProc;
FElementParam: TObject;
public
constructor Create(const ATypeInfo: PTypeInfo; const ASize: Integer;
const AElementType: PTypeInfo; const AElementSize: Integer;
const AElementInfo: TBaseTypeInfo;
const AElementSerializeProc: TSerializeProc;
const AElementDeserializeProc: TDeserializeProc;
const AElementParam: TObject);
property ElementType: PTypeInfo read FElementType;
property ElementSize: Integer read FElementSize;
property ElementInfo: TBaseTypeInfo read FElementInfo;
property ElementSerializeProc: TSerializeProc read FElementSerializeProc;
property ElementDeserializeProc: TDeserializeProc read FElementDeserializeProc;
property ElementParam: TObject read FElementParam;
end;
private
class var FTypeInfoMap: TObjectDictionary<Pointer, TBaseTypeInfo>;
class var FTypeInfoMapLock: TCriticalSection;
private
class function RegisterRecordTypeInfo(const ATypeInfo: Pointer): TRecordTypeInfo; static;
class function RegisterArrayTypeInfo(const ATypeInfo: PTypeInfo): TArrayTypeInfo; static;
class function GetSerializationProcs(const AType: TRttiType;
out ASerializeProc: TSerializeProc; out ADeserializeProc: TDeserializeProc;
out AParam: TObject): Boolean; static;
private
class procedure SerializeUInt8(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeUInt16(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeUInt32(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeUInt64(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeInt8(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeInt16(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeInt32(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeInt64(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeFixed32(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeFixed64(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeUString(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeRecord(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeBytes(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeDynArrayPacked(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure SerializeDynArrayUnpacked(const AWriter: TWriter;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
private
class procedure DeserializeUInt8(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeUInt16(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeUInt32(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeUInt64(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeInt8(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeInt16(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeInt32(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeInt64(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeFixed32(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeFixed64(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeUString(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeBytes(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeRecord(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeDynArrayPacked(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
class procedure DeserializeDynArrayUnpacked(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject); static;
public
{ @exclude }
class constructor Create;
{ @exclude }
class destructor Destroy;
{$ENDREGION 'Internal Declarations'}
public
{ Serializes a record to an array of bytes.
Parameters:
T: the type of the record to serialize.
ARecord: the record (of type T) to serialize.
Returns:
A byte array containing the serialized record. }
class function Serialize<T: record>(const ARecord: T): TBytes; overload; static; inline;
{ Serializes a record to an array of bytes.
Parameters:
ARecordType: the type of the record to serialize. This is the result
from a TypeInfo(TMyRecord) call.
ARecord: the record (of ARecordType) to serialize.
Returns:
A byte array containing the serialized record. }
class function Serialize(const ARecordType: Pointer;
const ARecord): TBytes; overload; static;
{ Serializes a record to a file.
Parameters:
T: the type of the record to serialize.
ARecord: the record (of type T) to serialize.
AFilename: the name of the file to serialize the record to. }
class procedure Serialize<T: record>(const ARecord: T;
const AFilename: String); overload; static; inline;
{ Serializes a record to a file.
Parameters:
ARecordType: the type of the record to serialize. This is the result
from a TypeInfo(TMyRecord) call.
ARecord: the record (of ARecordType) to serialize.
AFilename: the name of the file to serialize the record to. }
class procedure Serialize(const ARecordType: Pointer; const ARecord;
const AFilename: String); overload; static;
{ Serializes a record to a stream.
Parameters:
T: the type of the record to serialize.
ARecord: the record (of type T) to serialize.
AStream: the stream to serialize the record to. }
class procedure Serialize<T: record>(const ARecord: T;
const AStream: TStream); overload; static; inline;
{ Serializes a record to a stream.
Parameters:
ARecordType: the type of the record to serialize. This is the result
from a TypeInfo(TMyRecord) call.
ARecord: the record (of ARecordType) to serialize.
AStream: the stream to serialize the record to. }
class procedure Serialize(const ARecordType: Pointer; const ARecord;
const AStream: TStream); overload; static;
{ Deserializes a record from an array of bytes.
When the record contains a parameterless @code(Initialize) procedure, then
that procedure will be called before the record is deserialized.
Parameters:
T: the type of the record to deserialize.
ARecord: the record (of type T) to deserialize.
AData: the byte array containing the serialized record. }
class procedure Deserialize<T: record>(out ARecord: T;
const AData: TBytes); overload; static; inline;
{ Deserializes a record from an array of bytes.
When the record contains a parameterless @code(Initialize) procedure, then
that procedure will be called before the record is deserialized.
Parameters:
ARecordType: the type of the record to deserialize. This is the result
from a TypeInfo(TMyRecord) call.
ARecord: the record (of ARecordType) to deserialize.
AData: the byte array containing the serialized record. }
class procedure Deserialize(const ARecordType: Pointer; out ARecord;
const AData: TBytes); overload; static;
{ Deserializes a record from a memory buffer.
When the record contains a parameterless @code(Initialize) procedure, then
that procedure will be called before the record is deserialized.
Parameters:
T: the type of the record to deserialize.
ARecord: the record (of type T) to deserialize.
ABuffer: the memory buffer containing the serialized record.
ABufferSize: the size of the buffer }
class procedure Deserialize<T: record>(out ARecord: T; const ABuffer: Pointer;
const ABufferSize: Integer); overload; static; inline;
{ Deserializes a record from a stream.
When the record contains a parameterless @code(Initialize) procedure, then
that procedure will be called before the record is deserialized.
Parameters:
T: the type of the record to deserialize.
ARecordType: the type of the record to deserialize. This is the result
from a TypeInfo(TMyRecord) call.
ARecord: the record (of ARecordType) to deserialize.
ABuffer: the memory buffer containing the serialized record.
ABufferSize: the size of the buffer }
class procedure Deserialize(const ARecordType: Pointer; out ARecord;
const ABuffer: Pointer; const ABufferSize: Integer); overload; static;
{ Deserializes a record from a file.
When the record contains a parameterless @code(Initialize) procedure, then
that procedure will be called before the record is deserialized.
Parameters:
T: the type of the record to deserialize.
ARecord: the record (of type T) to deserialize.
AFilename: the name of the file containing the serialized record. }
class procedure Deserialize<T: record>(out ARecord: T; const AFilename: String); overload; static; inline;
{ Deserializes a record from a file.
When the record contains a parameterless @code(Initialize) procedure, then
that procedure will be called before the record is deserialized.
Parameters:
ARecordType: the type of the record to deserialize. This is the result
from a TypeInfo(TMyRecord) call.
ARecord: the record (of ARecordType) to deserialize.
AFilename: the name of the file containing the serialized record. }
class procedure Deserialize(const ARecordType: Pointer; out ARecord;
const AFilename: String); overload; static;
{ Deserializes a record from a stream.
When the record contains a parameterless @code(Initialize) procedure, then
that procedure will be called before the record is deserialized.
Parameters:
T: the type of the record to deserialize.
ARecord: the record (of type T) to deserialize.
AStream: the stream containing the serialized record. }
class procedure Deserialize<T: record>(out ARecord: T; const AStream: TStream); overload; static; inline;
{ Deserializes a record from a stream.
When the record contains a parameterless @code(Initialize) procedure, then
that procedure will be called before the record is deserialized.
Parameters:
T: the type of the record to deserialize.
ARecordType: the type of the record to deserialize. This is the result
from a TypeInfo(TMyRecord) call.
ARecord: the record (of ARecordType) to deserialize.
AStream: the stream containing the serialized record. }
class procedure Deserialize(const ARecordType: Pointer; out ARecord;
const AStream: TStream); overload; static;
{ Registers a record for serialization in Protocol Buffer format. This is
only needed for use with Free Pascal. When using Delphi, the record type is
automatically registered when it is first (de)serialized.
You can also use this method to register 3rd party or RTL record types.
Every record type you want to use for serialization must be registered
once and only once. You usually do this at application startup. If a
record has fields of other record types, then those other record types
must be registered as well.
To register a record, you must declare a dummy variable of the record
type and then call this method as in the following example:
<source>
var
P: TPerson; // Dummy variable
begin
TgoProtocolBuffer.Register(TypeInfo(TPerson), P, @TPerson.Initialize,
[@P.Name, 1, @P.Id, 2, @P.Email, 3, @P.Phone, 4]);
end;
</source>
The parameters are the @code(TypeInfo(..)) of the record type, the dummy
variable, the optional address of an Initialize method and an array of
tags and field addresses.
The dummy variable is just used as a helper to pass the field addresses.
You don't need to initialize this variable with any data.
Before a record of this type is deserialized, its fields are always
cleared (set to 0 or nil). You can perform additional initialization after
this by specifying an Initialize method. If set, that method will be
called after clearing all fields, but before deserializing. Pass nil to
clear the record only.
The final parameter is an array of tags and field addresses. Each tag
uniquely identifies the corresponding field. Tags must be in the range
1-536870911. Tags must be unique within the record and each tag must have
a corresponding field address. If the number of tags doesn't match the
number of addresses, or if there are any other invalid parameters, then an
exception is raised.
You can pass the tags and field addresses in any way you want, as long as
you pass the tags in the same order as the corresponding field addresses.
You can use the (Field, Tag)* order as in the example above, or the
opposite (Tag, Field)* order as in this example:
<source>[1, @P.Name, 2, @P.Id, 3, @P.Email, 4, @P.Phone]</source>
You can also specify all fields first, followed by all tags, or the other
way around:
<source>[@P.Name, @P.Id, @P.Email, @P.Phone, 1, 2, 3, 4]</source>
Or any other combination that makes sense in the declaration:
<source>
[@P.Name, @P.Id,
1 , 2,
@P.Email, @P.Phone,
3 , 4]
</source>
Just remember that the order of the tags must match the order of the
fields.
Parameters:
ARecordType: the type of the record to register. This is the result
from a TypeInfo(TMyRecord) call.
ARecord: a dummy instance of the record type to register (of type
ARecordType).
AInitializeProc: the record method to call to initialize the record
with its default values.
AFields: an array of tags and record field addresses. See the
documentation above for more information. }
class procedure Register(const ARecordType: Pointer; const ARecord;
const AInitializeProc: TInitializeProc; const AFields: array of const); static;
end;
implementation
uses
Grijjy.Collections;
const
WIRE_TYPE_VARINT = 0;
WIRE_TYPE_64BIT = 1;
WIRE_TYPE_VARIABLE_SIZE = 2;
WIRE_TYPE_START_GROUP = 3;
WIRE_TYPE_END_GROUP = 4;
WIRE_TYPE_32BIT = 5;
type
PInt8 = ^Int8;
PInt16 = ^Int16;
PInt32 = ^Int32;
PUInt8 = ^UInt8;
PUInt16 = ^UInt16;
PUInt32 = ^UInt32;
{ SerializeAttribute }
constructor SerializeAttribute.Create(const ATag: TgoSerializationTag);
begin
inherited Create;
FTag := ATag;
end;
{ TgoProtocolBuffer }
class constructor TgoProtocolBuffer.Create;
begin
FTypeInfoMap := TObjectDictionary<Pointer, TBaseTypeInfo>.Create([doOwnsValues]);
FTypeInfoMapLock := TCriticalSection.Create;
end;
class procedure TgoProtocolBuffer.Deserialize<T>(out ARecord: T;
const AData: TBytes);
begin
Deserialize(TypeInfo(T), ARecord, AData);
end;
class procedure TgoProtocolBuffer.Deserialize<T>(out ARecord: T;
const ABuffer: Pointer; const ABufferSize: Integer);
begin
Deserialize(TypeInfo(T), ARecord, ABuffer, ABufferSize);
end;
class procedure TgoProtocolBuffer.Deserialize<T>(out ARecord: T;
const AFilename: String);
begin
Deserialize(TypeInfo(T), ARecord, AFilename);
end;
class procedure TgoProtocolBuffer.Deserialize<T>(out ARecord: T;
const AStream: TStream);
begin
Deserialize(TypeInfo(T), ARecord, AStream);
end;
class procedure TgoProtocolBuffer.Deserialize(const ARecordType: Pointer;
out ARecord; const AData: TBytes);
begin
Deserialize(ARecordType, ARecord, Pointer(AData), Length(AData));
end;
class procedure TgoProtocolBuffer.Deserialize(const ARecordType: Pointer;
out ARecord; const ABuffer: Pointer; const ABufferSize: Integer);
var
RecordTypeInfo: TRecordTypeInfo;
RecordPtr: Pointer;
Reader: TReader;
begin
RecordPtr := @ARecord;
RecordTypeInfo := RegisterRecordTypeInfo(ARecordType);
Reader := TReader.Create(ABuffer, ABufferSize);
try
RecordTypeInfo.Deserialize(Reader, RecordPtr);
finally
Reader.Free;
end;
end;
class procedure TgoProtocolBuffer.Deserialize(const ARecordType: Pointer;
out ARecord; const AFilename: String);
var
Stream: TFileStream;
begin
Stream := TFileStream.Create(AFilename, fmOpenRead or fmShareDenyWrite);
try
Deserialize(ARecordType, ARecord, Stream);
finally
Stream.Free;
end;
end;
class procedure TgoProtocolBuffer.Deserialize(const ARecordType: Pointer;
out ARecord; const AStream: TStream);
var
Bytes: TBytes;
begin
SetLength(Bytes, AStream.Size - AStream.Position);
if Assigned(Bytes) then
AStream.ReadBuffer(Bytes[0], Length(Bytes));
Deserialize(ARecordType, ARecord, Bytes);
end;
class procedure TgoProtocolBuffer.Register(const ARecordType: Pointer; const ARecord;
const AInitializeProc: TInitializeProc; const AFields: array of const);
var
Context: TRttiContext;
RecordAddress, RecordEndAddress: NativeUInt;
RecordType, FieldType: TRttiType;
RecordTypeInfo: TRecordTypeInfo;
Tags: TArray<Integer>;
Offsets: TArray<NativeUInt>;
TagSet: TgoSet<Integer>;
OffsetToTag: TDictionary<NativeUInt, Integer>;
OffsetsToIgnore: TgoSet<NativeUInt>;
I, FieldCount, TagCount, OffsetCount, Count, Tag: Integer;
V: TVarRec;
Fields: TArray<TRttiField>;
Field: TRttiField;
FieldInfo: TFieldTypeInfo;
FieldInfos: TArray<TFieldTypeInfo>;
SerializeProc: TSerializeProc;
DeserializeProc: TDeserializeProc;
Param: TObject;
begin
Assert(Assigned(FTypeInfoMap));
if (ARecordType = nil) then
raise EgoSerializationError.Create('Invalid call to TgoProtocolBuffer.Register. ARecordType cannot be nil.');
if (FTypeInfoMap.ContainsKey(ARecordType)) then
raise EgoSerializationError.Create('Invalid call to TgoProtocolBuffer.Register. Duplicate registration of type ' + GetTypeName(ARecordType));
Context := TRttiContext.Create;
RecordType := Context.GetType(ARecordType);
if (RecordType = nil) then
raise EgoSerializationError.Create('Unable to get data type for type ' + GetTypeName(ARecordType));
if (Length(AFields) = 0) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). No fields specified.', [RecordType.Name]);
if (Odd(Length(AFields))) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Number of elements in AFields array must be even.', [RecordType.Name]);
RecordAddress := NativeUInt(@ARecord);
RecordEndAddress := RecordAddress + NativeUInt(RecordType.TypeSize);
FieldCount := Length(AFields) div 2;
SetLength(Tags, FieldCount);
SetLength(Offsets, FieldCount);
TagCount := 0;
OffsetCount := 0;
TagSet := TgoSet<Integer>.Create;
try
{ Sort all AFields values into tags and offsets }
for I := 0 to Length(AFields) - 1 do
begin
V := AFields[I];
if (V.VType = vtInteger) then
begin
if (TagCount >= FieldCount) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Too many tags specified.', [RecordType.Name]);
if (TagSet.Contains(V.VInteger)) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Duplicate tag %d.', [RecordType.Name, V.VInteger]);
if ((V.VInteger < 1) or (V.VInteger > 536870911)) and (V.VInteger <> -1) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Tag %d must be between 1 and 536870911.', [RecordType.Name, V.VInteger]);
TagSet.Add(V.VInteger);
Tags[TagCount] := V.VInteger;
Inc(TagCount);
end
else if (V.VType = vtPointer) then
begin
if (OffsetCount >= FieldCount) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Too many field addresses specified.', [RecordType.Name]);
if (NativeUInt(V.VPointer) < RecordAddress) or (NativeUInt(V.VPointer) >= RecordEndAddress) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Field address does not belong to record.', [RecordType.Name]);
Offsets[OffsetCount] := NativeUInt(V.VPointer) - RecordAddress;
Inc(OffsetCount);
end
else
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Each AFields element must be an Integer (tag) or Pointer (field address).', [RecordType.Name]);
end;
finally
TagSet.Free;
end;
if (TagCount <> FieldCount) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Insufficient number of tags specified.', [RecordType.Name]);
if (OffsetCount <> FieldCount) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Insufficient number of field addresses specified.', [RecordType.Name]);
Count := 0;
OffsetsToIgnore := nil;
OffsetToTag := TDictionary<NativeUInt, Integer>.Create;
try
OffsetsToIgnore := TgoSet<NativeUInt>.Create;
for I := 0 to FieldCount - 1 do
begin
if (Tags[I] > 0) then
begin
if (OffsetToTag.TryGetValue(Offsets[I], Tag)) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Duplicate field offset %d (tags %d and %d).', [RecordType.Name, Offsets[I], Tag, Tags[I]]);
OffsetToTag.Add(Offsets[I], Tags[I]);
end
else
OffsetsToIgnore.AddOrSet(Offsets[I]);
end;
Fields := RecordType.GetDeclaredFields;
SetLength(FieldInfos, FieldCount);
for Field in Fields do
begin
if (OffsetToTag.TryGetValue(Field.Offset, Tag)) then
begin
FieldType := Field.FieldType;
if (not GetSerializationProcs(FieldType, SerializeProc, DeserializeProc, Param)) then
begin
if (OffsetsToIgnore.Contains(Field.Offset)) then
Continue;
if (FieldType.TypeKind in [tkString, tkLString, tkWString]) then
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Unsupported data type "%s". Note that string types other than UnicodeString are not supported.', [RecordType.Name, FieldType.Name])
else
raise EgoSerializationError.CreateFmt('Invalid call to TgoProtocolBuffer.Register(%s). Unsupported data type "%s".', [RecordType.Name, FieldType.Name]);
end;
Assert(Count < FieldCount);
FieldInfo := TFieldTypeInfo.Create(Tag, Field.Offset, SerializeProc, DeserializeProc, Param);
FieldInfos[Count] := FieldInfo;
Inc(Count);
{ Remove this field offset. This is to support variant parts in record.
For example, TRectF is defined as:
TRectF = record
case Integer of
0: (Left, Top, Right, Bottom: Single);
1: (TopLeft, BottomRight: TPointF);
end;
Both Left and TopLeft have the same offset. However, once Left has
been processed, we don't want to process TopLeft anymore.
NOTE: this means that only the "first variants" in a variant record
can be registered (the 4 Single fields in this example }
OffsetToTag.Remove(Field.Offset);
end;
end;
finally
OffsetsToIgnore.Free;
OffsetToTag.Free;
end;
if (Count = 0) then
raise EgoSerializationError.CreateFmt('Unable register record type %s. It does not contain any [Serialize] fields',
[RecordType.Name]);
SetLength(FieldInfos, Count);
RecordTypeInfo := TRecordTypeInfo.Create(ARecordType, RecordType.TypeSize, AInitializeProc, FieldInfos);
{ Another thread may already have registered the same type in the meantime.
In that case, ignore this one and use the existing type. }
Assert(Assigned(FTypeInfoMap));
Assert(Assigned(FTypeInfoMapLock));
FTypeInfoMapLock.Enter;
try
if (FTypeInfoMap.ContainsKey(ARecordType)) then
{ Ignore and free the type we just created. }
FreeAndNil(RecordTypeInfo)
else
FTypeInfoMap.Add(ARecordType, RecordTypeInfo);
finally
FTypeInfoMapLock.Leave;
end;
end;
class procedure TgoProtocolBuffer.DeserializeBytes(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject);
type
PBytes = ^TBytes;
var
Len: Integer;
Bytes: TBytes;
P: PBytes;
begin
Len := AReader.ReadVarUInt;
if (Len > 0) then
begin
SetLength(Bytes, Len);
AReader.ReadBytes(Bytes[0], Len);
end;
P := @ARecord[AOffset];
P^ := Bytes;
end;
class procedure TgoProtocolBuffer.DeserializeDynArrayPacked(const AReader: TReader;
const ARecord: PByte; const ATag, AOffset: Integer; const AParam: TObject);
var
ArrayInfo: TArrayTypeInfo absolute AParam;
ElementDeserializeProc: TDeserializeProc;
ElementParam: TObject;
ElementSize, Len, EndIndex, Count: Integer;
Capacity: NativeInt;
PA: PPointer;
P: Pointer;
Element: PByte;
begin
Assert(Assigned(AParam));
Assert(AParam is TArrayTypeInfo);
ElementDeserializeProc := ArrayInfo.ElementDeserializeProc;
ElementParam := ArrayInfo.ElementParam;
ElementSize := ArrayInfo.ElementSize;
PA := @ARecord[AOffset];
P := PA^;
Element := P;
Len := AReader.ReadVarUInt;
EndIndex := AReader.Index + Len;
Count := 0;
Capacity := 0;
while (AReader.Index < EndIndex) do
begin
if (Count >= Capacity) then
begin
Inc(Capacity, 16);
DynArraySetLength(P, ArrayInfo.TypeInfo, 1, @Capacity);
Element := PByte(P) + (Count * ElementSize);
end;
Inc(Count);
ElementDeserializeProc(AReader, Element, ATag, 0, ElementParam);
Inc(Element, ElementSize);
end;
Assert(AReader.Index = EndIndex);
Capacity := Count;
DynArraySetLength(P, ArrayInfo.TypeInfo, 1, @Capacity);
PA^ := P;
end;
class procedure TgoProtocolBuffer.DeserializeDynArrayUnpacked(
const AReader: TReader; const ARecord: PByte; const ATag, AOffset: Integer;
const AParam: TObject);
var
ArrayInfo: TArrayTypeInfo absolute AParam;
ElementDeserializeProc: TDeserializeProc;
ElementParam: TObject;
PA: PPointer;
P: Pointer;
Element: PByte;
Count, NextTag, Size, ElementSize: Integer;
Capacity: NativeInt;
begin
Assert(Assigned(AParam));
Assert(AParam is TArrayTypeInfo);
ElementDeserializeProc := ArrayInfo.ElementDeserializeProc;
ElementParam := ArrayInfo.ElementParam;
ElementSize := ArrayInfo.ElementSize;
PA := @ARecord[AOffset];
P := PA^;
Element := P;
Count := 0;
Capacity := 0;
while True do
begin
if (Count >= Capacity) then
begin
Inc(Capacity, 16);
DynArraySetLength(P, ArrayInfo.TypeInfo, 1, @Capacity);
Element := PByte(P) + (Count * ElementSize);
end;