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-rw-r--r--src/classes/URingBuffer.pas128
1 files changed, 0 insertions, 128 deletions
diff --git a/src/classes/URingBuffer.pas b/src/classes/URingBuffer.pas
deleted file mode 100644
index ce51e209..00000000
--- a/src/classes/URingBuffer.pas
+++ /dev/null
@@ -1,128 +0,0 @@
-unit URingBuffer;
-
-interface
-
-{$IFDEF FPC}
- {$MODE Delphi}
-{$ENDIF}
-
-{$I switches.inc}
-
-uses
- SysUtils;
-
-type
- TRingBuffer = class
- private
- RingBuffer: PChar;
- BufferCount: integer;
- BufferSize: integer;
- WritePos: integer;
- ReadPos: integer;
- public
- constructor Create(Size: integer);
- destructor Destroy; override;
- function Read(Buffer: PChar; Count: integer): integer;
- function Write(Buffer: PChar; Count: integer): integer;
- procedure Flush();
- end;
-
-implementation
-
-uses
- Math;
-
-constructor TRingBuffer.Create(Size: integer);
-begin
- BufferSize := Size;
-
- GetMem(RingBuffer, Size);
- if (RingBuffer = nil) then
- raise Exception.Create('No memory');
-end;
-
-destructor TRingBuffer.Destroy;
-begin
- FreeMem(RingBuffer);
-end;
-
-function TRingBuffer.Read(Buffer: PChar; Count: integer): integer;
-var
- PartCount: integer;
-begin
- // adjust output count
- if (Count > BufferCount) then
- begin
- //DebugWriteln('Read too much: ' + inttostr(count) +',count:'+ inttostr(BufferCount) + '/size:' + inttostr(BufferSize));
- Count := BufferCount;
- end;
-
- // check if there is something to do
- if (Count <= 0) then
- begin
- Result := Count;
- Exit;
- end;
-
- // copy data to output buffer
-
- // first step: copy from the area between the read-position and the end of the buffer
- PartCount := Min(Count, BufferSize - ReadPos);
- Move(RingBuffer[ReadPos], Buffer[0], PartCount);
-
- // second step: if we need more data, copy from the beginning of the buffer
- if (PartCount < Count) then
- Move(RingBuffer[0], Buffer[0], Count-PartCount);
-
- // mark the copied part of the buffer as free
- BufferCount := BufferCount - Count;
- ReadPos := (ReadPos + Count) mod BufferSize;
-
- Result := Count;
-end;
-
-function TRingBuffer.Write(Buffer: PChar; Count: integer): integer;
-var
- PartCount: integer;
-begin
- // check for a reasonable request
- if (Count <= 0) then
- begin
- Result := Count;
- Exit;
- end;
-
- // skip input data if the input buffer is bigger than the ring-buffer
- if (Count > BufferSize) then
- begin
- //DebugWriteln('Write skip data:' + inttostr(count) +',count:'+ inttostr(BufferCount) + '/size:' + inttostr(BufferSize));
- Buffer := @Buffer[Count - BufferSize];
- Count := BufferSize;
- end;
-
- // first step: copy to the area between the write-position and the end of the buffer
- PartCount := Min(Count, BufferSize - WritePos);
- Move(Buffer[0], RingBuffer[WritePos], PartCount);
-
- // second step: copy data to front of buffer
- if (PartCount < Count) then
- Move(Buffer[PartCount], RingBuffer[0], Count-PartCount);
-
- // update info
- BufferCount := Min(BufferCount + Count, BufferSize);
- WritePos := (WritePos + Count) mod BufferSize;
- // if the buffer is full, we have to reposition the read-position
- if (BufferCount = BufferSize) then
- ReadPos := WritePos;
-
- Result := Count;
-end;
-
-procedure TRingBuffer.Flush();
-begin
- ReadPos := 0;
- WritePos := 0;
- BufferCount := 0;
-end;
-
-end. \ No newline at end of file