Implement memchecker to ensure a drumkit fits into RAM.

It's a class that can calculate the available free RAM (or rather a rough
estimation of it) and the size of the drumkit when loaded into RAM
and provides a plugic method to check if the drumkit then fits into RAM.

3 files changed, 151 insertions, 0 deletions

diff --git a/src/Makefile.am.drumgizmo b/src/Makefile.am.drumgizmo
index 57b6362..3248702 100644
--- a/src/Makefile.am.drumgizmo
+++ b/src/Makefile.am.drumgizmo
@@ -18,6 +18,7 @@ DRUMGIZMO_SOURCES = \
 	$(top_srcdir)/src/events.cc \
 	$(top_srcdir)/src/instrument.cc \
 	$(top_srcdir)/src/instrumentparser.cc \
+	$(top_srcdir)/src/memchecker.cc \
 	$(top_srcdir)/src/messagehandler.cc \
 	$(top_srcdir)/src/messagereceiver.cc \
 	$(top_srcdir)/src/midimapparser.cc \
diff --git a/src/memchecker.cc b/src/memchecker.cc
new file mode 100644
index 0000000..b26603a
--- /dev/null
+++ b/src/memchecker.cc
@@ -0,0 +1,102 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ *            memchecker.cc
+ *
+ *  Sat Jan 16 18:27:52 CET 2016
+ *  Copyright 2016 André Nusser
+ *  andre.nusser@googlemail.com
+ ****************************************************************************/
+
+/*
+ *  This file is part of DrumGizmo.
+ *
+ *  DrumGizmo is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  DrumGizmo 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 General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with DrumGizmo; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
+ */
+#include "memchecker.h"
+
+#ifdef WIN32
+	#define WIN32_LEAN_AND_MEAN
+	#include <windows.h>
+#else
+	#include <sys/sysinfo.h>
+#endif
+#include <sndfile.h>
+#include <hugin.hpp>
+
+bool Memchecker::enoughFreeMemory(const DrumKit& drumkit) const
+{
+	size_t freeMemory = calcFreeMemory();
+	size_t neededMemory = calcNeededMemory(drumkit);
+
+	return freeMemory >= neededMemory;
+}
+
+size_t Memchecker::calcFreeMemory() const
+{
+	size_t free_memory(0);
+
+	// Platform specific calculation of the amount of free memory.
+#ifdef WIN32
+	MEMORYSTATUSEX status;
+	status.dwLength = sizeof(status);
+	GlobalMemoryStatusEx(&status);
+	free_memory = status.ullAvailPhys;
+#else
+	struct sysinfo sys_info;
+	sysinfo (&sys_info);
+	free_memory = sys_info.freeram * sys_info.mem_unit;
+#endif
+
+	DEBUG(memchecker, "Calculated %llu free memory.\n", (long long unsigned int)free_memory);
+
+	return free_memory;
+}
+
+size_t Memchecker::calcNeededMemory(const DrumKit& drumkit) const
+{
+	size_t needed_memory(0);
+
+	// Calculate memory usage of all instruments of drumkit.
+	for(auto instrument : drumkit.instruments)
+	{
+		const auto& audiofiles = instrument->audiofiles;
+
+		// Calculate memory usage of all audiofiles.
+		for(auto audiofile : audiofiles)
+		{
+			needed_memory += calcBytesPerChannel(audiofile->filename);
+		}
+	}
+
+	DEBUG(memchecker, "Calculated %llu needed memory.\n", (long long unsigned int)needed_memory);
+
+	return needed_memory;
+}
+
+size_t Memchecker::calcBytesPerChannel(const std::string& filename) const
+{
+	SF_INFO sf_info;
+
+	SNDFILE* f = sf_open(filename.c_str(), SFM_READ, &sf_info);
+	if(!f)
+	{
+		ERR(memchecker, "SNDFILE Error (%s): %s\n", filename.c_str(), sf_strerror(f));
+		return 0;
+	}
+
+	sf_close(f);
+
+	return sf_info.frames * sizeof(sample_t);
+}
diff --git a/src/memchecker.h b/src/memchecker.h
new file mode 100644
index 0000000..c3e13c2
--- /dev/null
+++ b/src/memchecker.h
@@ -0,0 +1,48 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ *            memchecker.h
+ *
+ *  Sat Jan 16 18:27:52 CET 2016
+ *  Copyright 2016 André Nusser
+ *  andre.nusser@googlemail.com
+ ****************************************************************************/
+
+/*
+ *  This file is part of DrumGizmo.
+ *
+ *  DrumGizmo is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  DrumGizmo 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 General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with DrumGizmo; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
+ */
+#pragma once
+
+#include "drumkit.h"
+
+#include <string>
+
+class Memchecker
+{
+public:
+	 //! Checks if there is enough memory left to load drumkit into RAM.
+	 //! \param drumkit The drumkit for which it is checked if there's enough memory left.
+	 //! \return True iff there is enough memory left.
+	bool enoughFreeMemory(const DrumKit& drumkit) const;
+
+protected:
+	// Computes how much RAM (in bytes) is left.
+	size_t calcFreeMemory() const;
+	// Computes how much memory the drumkit takes when loaded into RAM (in bytes).
+	size_t calcNeededMemory(const DrumKit& drumkit) const;
+	// Computes the number of bytes per channel of <filename> using libsnd.
+	size_t calcBytesPerChannel(const std::string& filename) const;
+};