Pascal (Lazarus/Delphi)

Compute Glacier SHA256 Tree Hash of a File

See more Amazon Glacier Examples

Computes the Amazon Glacier SHA256 tree hash for a file.

Note: This example requires Chilkat v9.5.0.78 or greater.

Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.Crypt2;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  crypt: TCrypt2;
  treeHashHex: string;

begin
  //  This example requires the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  crypt := TCrypt2.Create;

  //  For more information about Amazon Glacier tree hashes, see Computing Glacier Checksums
  //  Chilkat added the "sha256-tree-hash" algorithm in v9.5.0.78 to make it easy to compute the Glacier tree hash checksum
  //  of a file or from bytes in memory.
  crypt.HashAlgorithm := 'sha256-tree-hash';

  //  Return the hash in lowercase hexidecimal format.
  crypt.EncodingMode := 'hexlower';

  treeHashHex := crypt.HashFileENC('qa_data/jpg/penguins.jpg');
  WriteLn('SHA256 tree hash = ' + treeHashHex);


  crypt.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.