1 files changed, 152 insertions, 0 deletions
diff --git a/xsd-examples/cxx/tree/compression/compressed-format-target.cxx b/xsd-examples/cxx/tree/compression/compressed-format-target.cxx
new file mode 100644
index 0000000..2d150a0
--- /dev/null
+++ b/xsd-examples/cxx/tree/compression/compressed-format-target.cxx
@@ -0,0 +1,152 @@
+// file      : cxx/tree/compression/compressed-format-target.cxx
+// copyright : not copyrighted - public domain
+
+#include <ostream>
+#include <cstring> // std::memcpy
+
+#include "compressed-format-target.hxx"
+
+using namespace std;
+
+//
+// compression_failure
+//
+
+const char* compression_failure::
+what () const throw ()
+{
+  return "compression failure";
+}
+
+//
+// compressed_format_target
+//
+
+compressed_format_target::
+compressed_format_target (ostream& os, compression_type t)
+    : os_ (os), closed_ (false), n_ (0)
+  {
+    zs_.zalloc = Z_NULL;
+    zs_.zfree  = Z_NULL;
+    zs_.opaque = Z_NULL;
+
+    int window = 0;
+
+    switch (t)
+    {
+    case raw:
+      {
+        window = -15;
+        break;
+      }
+    case zlib:
+      {
+        window = 15;
+        break;
+      }
+    case gzip:
+      {
+        window = 16 + 15;
+        break;
+      }
+    }
+
+    int r (deflateInit2 (&zs_,
+                         Z_DEFAULT_COMPRESSION,
+                         Z_DEFLATED,
+                         window,
+                         8,
+                         Z_DEFAULT_STRATEGY));
+    if (r != Z_OK)
+      throw compression_failure (r);
+  }
+
+compressed_format_target::
+~compressed_format_target ()
+{
+  try
+  {
+    // Close the free the compression stream.
+    //
+    if (!closed_)
+      close ();
+  }
+  catch (...)
+  {
+  }
+
+  deflateEnd (&zs_);
+}
+
+void compressed_format_target::
+writeChars (const XMLByte* const buf,
+            const XMLSize_t size,
+            xercesc::XMLFormatter* const)
+{
+  // Flush the buffer if the block is too large or if we don't have
+  // any space left.
+  //
+  if ((size >= buf_size_ / 8 || n_ + size > buf_size_) && n_ != 0)
+  {
+    write (in_, n_);
+    n_ = 0;
+  }
+
+  if (size < buf_size_ / 8)
+  {
+    memcpy (in_ + n_, reinterpret_cast<const char*> (buf), size);
+    n_ += size;
+  }
+  else
+    write (reinterpret_cast<const char*> (buf), size);
+}
+
+
+void compressed_format_target::
+flush ()
+{
+  if (n_ != 0)
+  {
+    write (in_, n_);
+    n_ = 0;
+  }
+
+  if (!os_.fail ())
+    os_.flush ();
+}
+
+void compressed_format_target::
+close ()
+{
+  write (in_, n_, true);
+  n_ = 0;
+
+  if (!os_.fail ())
+    os_.flush ();
+
+  closed_ = true;
+}
+
+void compressed_format_target::
+write (const char* buf, size_t size, bool flush)
+{
+  zs_.next_in = reinterpret_cast<Bytef*> (const_cast<char*> (buf));
+  zs_.avail_in = static_cast<uInt> (size);
+
+  do
+  {
+    zs_.next_out = reinterpret_cast<Bytef*> (out_);
+    zs_.avail_out = buf_size_;
+
+    int r (deflate (&zs_, flush ? Z_FINISH : Z_NO_FLUSH));
+
+    if (r != Z_OK && r != Z_BUF_ERROR && r != Z_STREAM_END)
+      throw compression_failure (r);
+
+    size_t n (buf_size_ - zs_.avail_out);
+
+    if (!os_.fail () && n > 0)
+      os_.write (out_, static_cast<streamsize> (n));
+
+  } while (zs_.avail_out == 0);
+}