1 files changed, 120 insertions, 0 deletions
diff --git a/src/io/stream/gzipstream.h b/src/io/stream/gzipstream.h
new file mode 100644
index 0000000..202b3a1
--- /dev/null
+++ b/src/io/stream/gzipstream.h
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#ifndef SEEN_INKSCAPE_IO_GZIPSTREAM_H
+#define SEEN_INKSCAPE_IO_GZIPSTREAM_H
+/**
+ * @file
+ * Zlib-enabled input and output streams.
+ *
+ * This is a thin wrapper of libz calls, in order
+ * to provide a simple interface to our developers
+ * for gzip input and output.
+ */
+/*
+ * Authors:
+ *   Bob Jamison <rjamison@titan.com>
+ *
+ * Copyright (C) 2004 Inkscape.org
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <vector>
+#include "inkscapestream.h"
+#include <zlib.h>
+
+namespace Inkscape
+{
+namespace IO
+{
+
+//#########################################################################
+//# G Z I P    I N P U T    S T R E A M
+//#########################################################################
+
+/**
+ * This class is for deflating a gzip-compressed InputStream source
+ *
+ */
+class GzipInputStream : public BasicInputStream
+{
+
+public:
+
+    GzipInputStream(InputStream &sourceStream);
+    
+    ~GzipInputStream() override;
+    
+    int available() override;
+    
+    void close() override;
+    
+    int get() override;
+    
+private:
+
+    bool load();
+    int fetchMore();
+
+    bool loaded;
+    
+    unsigned char *outputBuf;
+    unsigned char *srcBuf;
+
+    unsigned long crc;
+    unsigned long srcCrc;
+    unsigned long srcSiz;
+    unsigned long srcLen;
+    long outputBufPos;
+    long outputBufLen;
+
+    z_stream d_stream;
+}; // class GzipInputStream
+
+
+
+
+//#########################################################################
+//# G Z I P    O U T P U T    S T R E A M
+//#########################################################################
+
+/**
+ * This class is for gzip-compressing data going to the
+ * destination OutputStream
+ *
+ */
+class GzipOutputStream : public BasicOutputStream
+{
+
+public:
+
+    GzipOutputStream(OutputStream &destinationStream);
+    
+    ~GzipOutputStream() override;
+    
+    void close() override;
+    
+    void flush() override;
+    
+    int put(char ch) override;
+
+private:
+
+    std::vector<unsigned char> inputBuf;
+
+    long totalIn;
+    long totalOut;
+    unsigned long crc;
+
+}; // class GzipOutputStream
+
+
+
+
+
+
+
+} // namespace IO
+} // namespace Inkscape
+
+
+#endif /* __INKSCAPE_IO_GZIPSTREAM_H__ */