Implement user-provided stream filters

Refactor QPDF_Stream to use stream filter classes to handle supported
stream filters as well.

1 files changed, 30 insertions, 0 deletions

diff --git a/libqpdf/qpdf/SF_ASCIIHexDecode.hh b/libqpdf/qpdf/SF_ASCIIHexDecode.hh
new file mode 100644
index 00000000..869d0722
--- /dev/null
+++ b/libqpdf/qpdf/SF_ASCIIHexDecode.hh
@@ -0,0 +1,30 @@
+#include <qpdf/QPDFStreamFilter.hh>
+#include <qpdf/Pl_ASCIIHexDecoder.hh>
+#include <memory>
+
+#ifndef SF_ASCIIHEXDECODE_HH
+#define SF_ASCIIHEXDECODE_HH
+
+class SF_ASCIIHexDecode: public QPDFStreamFilter
+{
+  public:
+    SF_ASCIIHexDecode() = default;
+    virtual ~SF_ASCIIHexDecode() = default;
+
+    virtual Pipeline* getDecodePipeline(Pipeline* next) override
+    {
+        this->pipeline = std::make_shared<Pl_ASCIIHexDecoder>(
+            "asciiHex decode", next);
+        return this->pipeline.get();
+    }
+
+    static std::shared_ptr<QPDFStreamFilter> factory()
+    {
+        return std::make_shared<SF_ASCIIHexDecode>();
+    }
+
+  private:
+    std::shared_ptr<Pipeline> pipeline;
+};
+
+#endif // SF_ASCIIHEXDECODE_HH