1 files changed, 166 insertions, 0 deletions
diff --git a/flow/pipebuffer.cc b/flow/pipebuffer.cc
new file mode 100644
index 0000000..bb6073a
--- /dev/null
+++ b/flow/pipebuffer.cc
@@ -0,0 +1,166 @@
+    /*
+
+    Copyright (C) 2000 Stefan Westerfeld
+                       stefan@space.twc.de
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+  
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Library General Public License for more details.
+   
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to
+    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+    Boston, MA 02111-1307, USA.
+
+    */
+
+#include "pipebuffer.h"
+#include <assert.h>
+#include <cstring>
+
+using namespace std;
+using namespace Arts;
+
+PipeSegment::PipeSegment(long size, void *buffer)
+{
+	this->buffer = new char[size];
+	this->currentpos = this->buffer;
+	memcpy(this->buffer,buffer,size);
+
+	_remaining = size;
+}
+
+PipeSegment::~PipeSegment()
+{
+	delete[] buffer;
+}
+
+void *PipeSegment::data()
+{
+	return currentpos;
+}
+
+long PipeSegment::remaining()
+{
+	return _remaining;
+}
+
+void PipeSegment::skip(long count)
+{
+	_remaining -= count;
+	currentpos += count;
+	assert(_remaining >= 0);
+}
+
+PipeBuffer::PipeBuffer()
+{
+	_size = 0;
+}
+
+PipeBuffer::~PipeBuffer()
+{
+	clear();
+}
+
+void PipeBuffer::clear()
+{
+	while(segments.size() != 0)
+	{
+		PipeSegment *first = *segments.begin();
+		delete first;
+
+		segments.pop_front();
+	}
+	_size = 0;
+}
+
+void *PipeBuffer::peek(long size)
+{
+	while(!segments.empty())
+	{
+		PipeSegment *first = *segments.begin();
+		if(size <= first->remaining())
+			return first->data();
+	}
+	return 0;
+}
+
+void PipeBuffer::skip(long size)
+{
+	while(!segments.empty() && size > 0)
+	{
+		PipeSegment *first = *segments.begin();
+
+		// if we have less data to skip than the first segment contains
+		if(size < first->remaining())
+		{
+			// skip the data inside the segment
+
+			_size -= size;
+			first->skip(size);
+			return;
+		}
+		else
+		{
+			// otherwise erase the first segment
+
+			_size -= first->remaining();
+			size -= first->remaining();
+
+			delete first;
+			segments.pop_front();
+		}
+	}
+}
+
+long PipeBuffer::read(long size, void *buffer)
+{
+	long readbytes = 0;
+	char *bptr = (char *)buffer;
+
+	while(!segments.empty() && size > 0)
+	{
+		PipeSegment *first = *segments.begin();
+		long readCnt = size;
+		if(readCnt > first->remaining()) readCnt = first->remaining();
+
+		memcpy(bptr,first->data(),readCnt);
+
+		first->skip(readCnt);
+		size -= readCnt;
+		bptr += readCnt;
+		readbytes += readCnt;
+
+		if(first->remaining() == 0)
+		{
+			delete first;
+			segments.pop_front();
+		}
+	}
+
+	_size -= readbytes;
+	return readbytes;
+}
+
+long PipeBuffer::size()
+{
+	return _size;
+}
+
+void PipeBuffer::write(long size, void *buffer)
+{
+	segments.push_back(new PipeSegment(size,buffer));
+	_size += size;
+}
+
+void PipeBuffer::unRead(long size, void *buffer)
+{
+	segments.push_front(new PipeSegment(size,buffer));
+	_size += size;
+}