Implement Pl_RunLength pipeline

1 files changed, 42 insertions, 0 deletions

diff --git a/include/qpdf/Pl_RunLength.hh b/include/qpdf/Pl_RunLength.hh
new file mode 100644
index 00000000..86855382
--- /dev/null
+++ b/include/qpdf/Pl_RunLength.hh
@@ -0,0 +1,42 @@
+// Copyright (c) 2005-2015 Jay Berkenbilt
+//
+// This file is part of qpdf.  This software may be distributed under
+// the terms of version 2 of the Artistic License which may be found
+// in the source distribution.  It is provided "as is" without express
+// or implied warranty.
+
+#ifndef __PL_RUNLENGTH_HH__
+#define __PL_RUNLENGTH_HH__
+
+#include <qpdf/Pipeline.hh>
+
+class Pl_RunLength: public Pipeline
+{
+  public:
+    enum action_e { a_encode, a_decode };
+
+    QPDF_DLL
+    Pl_RunLength(char const* identifier, Pipeline* next,
+                 action_e action);
+    QPDF_DLL
+    virtual ~Pl_RunLength();
+
+    QPDF_DLL
+    virtual void write(unsigned char* data, size_t len);
+    QPDF_DLL
+    virtual void finish();
+
+  private:
+    void encode(unsigned char* data, size_t len);
+    void decode(unsigned char* data, size_t len);
+    void flush_encode();
+
+    enum state_e { st_top, st_copying, st_run };
+
+    action_e action;
+    state_e state;
+    unsigned char buf[128];
+    unsigned int length;
+};
+
+#endif // __PL_RUNLENGTH_HH__