add pipeline-based stream data replacement function

git-svn-id: svn+q:///qpdf/trunk@990 71b93d88-0707-0410-a8cf-f5a4172ac649

1 files changed, 51 insertions, 4 deletions

diff --git a/libqpdf/QPDF_Stream.cc b/libqpdf/QPDF_Stream.cc
index 5e53b2ae..1f48b2c1 100644
--- a/libqpdf/QPDF_Stream.cc
+++ b/libqpdf/QPDF_Stream.cc
@@ -9,6 +9,7 @@
 #include <qpdf/Pl_ASCII85Decoder.hh>
 #include <qpdf/Pl_ASCIIHexDecoder.hh>
 #include <qpdf/Pl_LZWDecoder.hh>
+#include <qpdf/Pl_Count.hh>
 
 #include <qpdf/QTC.hh>
 #include <qpdf/QPDF.hh>
@@ -326,6 +327,32 @@ QPDF_Stream::pipeStreamData(Pipeline* pipeline, bool filter,
 	pipeline->write(b.getBuffer(), b.getSize());
 	pipeline->finish();
     }
+    else if (this->stream_provider.getPointer())
+    {
+	QPDFObjectHandle::StreamDataProvider& p =
+	    (*this->stream_provider.getPointer());
+	Pl_Count count("stream provider count", pipeline);
+	p.provideStreamData(this->objid, this->generation, &count);
+	size_t actual_length = count.getCount();
+	size_t desired_length =
+	    this->stream_dict.getKey("/Length").getIntValue();
+	if (actual_length == desired_length)
+	{
+	    QTC::TC("qpdf", "QPDF_Stream pipe use stream provider");
+	}
+	else
+	{
+	    QTC::TC("qpdf", "QPDF_Stream provider length mismatch");
+	    throw std::logic_error(
+		"stream data provider for " +
+		QUtil::int_to_string(this->objid) + " " +
+		QUtil::int_to_string(this->generation) +
+		" provided " +
+		QUtil::int_to_string(actual_length) +
+		" bytes instead of expected " +
+		QUtil::int_to_string(desired_length) + " bytes");
+	}
+    }
     else
     {
 	QTC::TC("qpdf", "QPDF_Stream pipe original stream data");
@@ -339,13 +366,33 @@ QPDF_Stream::pipeStreamData(Pipeline* pipeline, bool filter,
 
 void
 QPDF_Stream::replaceStreamData(PointerHolder<Buffer> data,
-			       QPDFObjectHandle filter,
-			       QPDFObjectHandle decode_parms)
+			       QPDFObjectHandle const& filter,
+			       QPDFObjectHandle const& decode_parms)
 {
     this->stream_data = data;
+    this->stream_provider = 0;
+    replaceFilterData(filter, decode_parms, data.getPointer()->getSize());
+}
+
+void
+QPDF_Stream::replaceStreamData(
+    PointerHolder<QPDFObjectHandle::StreamDataProvider> provider,
+    QPDFObjectHandle const& filter,
+    QPDFObjectHandle const& decode_parms,
+    size_t length)
+{
+    this->stream_provider = provider;
+    this->stream_data = 0;
+    replaceFilterData(filter, decode_parms, length);
+}
+
+void
+QPDF_Stream::replaceFilterData(QPDFObjectHandle const& filter,
+			       QPDFObjectHandle const& decode_parms,
+			       size_t length)
+{
     this->stream_dict.replaceOrRemoveKey("/Filter", filter);
     this->stream_dict.replaceOrRemoveKey("/DecodeParms", decode_parms);
     this->stream_dict.replaceKey("/Length",
-				 QPDFObjectHandle::newInteger(
-				     data.getPointer()->getSize()));
+				 QPDFObjectHandle::newInteger(length));
 }