Changeset 6 for ProtocolBuffers/UProtocolBuffers.pas

Timestamp:

Oct 9, 2009, 1:44:09 PM (15 years ago)

Author:

george

Message:

• Přidáno: Generování hlavičky položek se značkou Tag a Wire typem.

File:

• ProtocolBuffers/UProtocolBuffers.pas (modified) (4 diffs)

ProtocolBuffers/UProtocolBuffers.pas

@@ +1 @@
+// http://code.google.com/intl/cs/apis/protocolbuffers/docs/overview.html
 unit UProtocolBuffers;
 
-{$mode delphi}{$H+}
+{$mode delphi}
 
 interface
 
 uses
-  Classes, SysUtils; 
+  Classes, SysUtils;
 
 type
-  TPBItemType = (itRequired, itOptional, itRepeated);
+  TPBItemMode = (imRequired, imOptional, imRepeated);
+  TPBItemType = (itVariant, it64bit, itLengthDelimited, itStartGroup,
+    itEndGroup, it32bit);
 
   TPBEnumeration = class
   end;
+
+  { TPBItem }
 
   TPBItem = class
@@ -18 +23 @@
     Tag: Integer;
     ItemType: TPBItemType;
+    ItemMode: TPBItemMode;
+    procedure SaveToStream(Stream: TStream); virtual;
   end;
 
@@ -36 +43 @@
   end;
 
+  { TPBMessage }
+
   TPBMessage = class(TPBItem)
     Items: TList; // TList<TPBItem>;
+    procedure SaveToStream(Stream: TStream); override;
+    constructor Create;
   end;
 
+  { TProtocolBuffer }
+
   TProtocolBuffer = class
+    BaseMessage: TPBMessage;
     procedure LoadFromStream(Stream: TStream);
     procedure SaveToStream(Stream: TStream);
-    PMMessage: TPBMessage;
+    destructor Destroy; override;
   end;
 
 implementation
+
+uses
+  UMemoryStreamEx;
 
 { TProtocolBuffer }
@@ -57 +74 @@
 procedure TProtocolBuffer.SaveToStream(Stream: TStream);
 begin
+  BaseMessage.SaveToStream(Stream);
+end;
 
+destructor TProtocolBuffer.Destroy;
+begin
+  if Assigned(BaseMessage) then BaseMessage.Free;
+  inherited Destroy;
+end;
+
+{ TPBMessage }
+
+procedure TPBMessage.SaveToStream(Stream: TStream);
+begin
+  inherited SaveToStream(Stream);
+end;
+
+constructor TPBMessage.Create;
+begin
+  ItemType := itLengthDelimited;
+end;
+
+{ TPBItem }
+
+procedure TPBItem.SaveToStream(Stream: TStream);
+var
+  ByteIndex: Byte;
+  Data: Byte;
+begin
+  with TMemoryStreamEx(Stream) do begin
+    Data := ((Tag and $f) shl 3) or (Integer(ItemType) and $7);
+    ByteIndex := 0;
+    while Tag > (1 shl (ByteIndex * 8 + 4)) do begin
+      WriteByte(Data or $80);
+      Data := (Tag shr (ByteIndex * 8 + 4)) and $7f;
+      Inc(ByteIndex);
+    end;
+    WriteByte(Data);
+  end
 end;