X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=blobdiff_plain;f=source%2Ffiltered.h;fp=source%2Ffiltered.h;h=057517547c5ea7aa9afdfd80a9f78ff2292bfa75;hp=0000000000000000000000000000000000000000;hb=dd318ef67b0c683c8306da0abf806e99cff346e9;hpb=a1375220342e0fc87c8c7065059dc8d49633f95b

diff --git a/source/filtered.h b/source/filtered.h
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+++ b/source/filtered.h
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+/* $Id$
+
+This file is part of libmspio
+Copyright © 2008  Mikko Rasa, Mikkosoft Productions
+Distributed under the LGPL
+*/
+
+#ifndef MSP_IO_FILTERED_H_
+#define MSP_IO_FILTERED_H_
+
+namespace Msp {
+namespace IO {
+
+template<typename B, typename F>
+class Filtered: public B
+{
+private:
+	struct Activator
+	{
+		Filtered &f;
+
+		Activator(Filtered &f_): f(f_) { f.active=true; }
+		~Activator() { f.active=false; }
+	};
+
+	F filter;
+	bool active;
+
+public:
+	Filtered(): filter(*this), active(false) { }
+
+	template<typename A0>
+	Filtered(A0 a0): B(a0), filter(*this), active(false) { }
+
+	template<typename A0, typename A1>
+	Filtered(A0 a0, A1 a1): B(a0, a1), filter(*this), active(false) { }
+
+	F &get_filter() { return filter; }
+protected:
+	virtual unsigned do_write(const char *b, unsigned s)
+	{
+		if(!active)
+		{
+			Activator a(*this);
+			return filter.write(b, s);
+		}
+		else
+			return B::do_write(b, s);
+	}
+
+	virtual unsigned do_read(char *b, unsigned s)
+	{
+		if(!active)
+		{
+			Activator a(*this);
+			return filter.read(b, s);
+		}
+		else
+			return B::do_read(b, s);
+	}
+};
+
+} // namespace IO
+} // namespace Msp
+
+#endif