NULL video dumper

Might be useful for abusing dumpavi for running emulation without UI
and to have autoexit.

src/video/null.cpp

@@ -0,0 +1,111 @@
+#include "core/advdumper.hpp"
+#include "core/dispatch.hpp"
+#include "core/instance.hpp"
+#include "core/moviedata.hpp"
+#include "core/moviefile.hpp"
+#include "core/messages.hpp"
+#include "core/rom.hpp"
+#include "library/serialization.hpp"
+#include "library/minmax.hpp"
+
+#include <iomanip>
+#include <cassert>
+#include <cstring>
+#include <cerrno>
+#include <cstring>
+#include <sstream>
+#include <fstream>
+#include <zlib.h>
+
+namespace
+{
+	void deleter_fn(void* f)
+	{
+		delete reinterpret_cast<std::ofstream*>(f);
+	}
+
+	class null_dump_obj : public dumper_base
+	{
+	public:
+		null_dump_obj(master_dumper& _mdumper, dumper_factory_base& _fbase, const std::string& mode,
+			const std::string& prefix)
+			: dumper_base(_mdumper, _fbase), mdumper(_mdumper)
+		{
+			try {
+				mdumper.add_dumper(*this);
+			} catch(std::bad_alloc& e) {
+				throw;
+			} catch(std::exception& e) {
+				std::ostringstream x;
+				x << "Error starting NULL dump: " << e.what();
+				throw std::runtime_error(x.str());
+			}
+		}
+		~null_dump_obj() throw()
+		{
+			mdumper.drop_dumper(*this);
+		}
+		void on_frame(struct framebuffer::raw& _frame, uint32_t fps_n, uint32_t fps_d)
+		{
+			//Do nothing.
+		}
+		void on_sample(short l, short r)
+		{
+			//Do nothing.
+		}
+		void on_rate_change(uint32_t n, uint32_t d)
+		{
+			//Do nothing.
+		}
+		void on_gameinfo_change(const master_dumper::gameinfo& gi)
+		{
+			//Do nothing.
+		}
+		void on_end()
+		{
+			delete this;
+		}
+	private:
+		master_dumper& mdumper;
+	};
+
+	class adv_null_dumper : public dumper_factory_base
+	{
+	public:
+		adv_null_dumper() : dumper_factory_base("INTERNAL-NULL")
+		{
+			ctor_notify();
+		}
+		~adv_null_dumper() throw();
+		std::set<std::string> list_submodes() throw(std::bad_alloc)
+		{
+			std::set<std::string> x;
+			return x;
+		}
+		unsigned mode_details(const std::string& mode) throw()
+		{
+			return target_type_special;
+		}
+		std::string mode_extension(const std::string& mode) throw()
+		{
+			return "";	//Nothing interesting.
+		}
+		std::string name() throw(std::bad_alloc)
+		{
+			return "NULL";
+		}
+		std::string modename(const std::string& mode) throw(std::bad_alloc)
+		{
+			return "";
+		}
+		null_dump_obj* start(master_dumper& _mdumper, const std::string& mode, const std::string& prefix)
+			throw(std::bad_alloc, std::runtime_error)
+		{
+			return new null_dump_obj(_mdumper, *this, mode, prefix);
+		}
+	} adv;
+
+	adv_null_dumper::~adv_null_dumper() throw()
+	{
+	}
+}