Add dummy and LevelDB database backends

1 files changed, 50 insertions, 0 deletions

diff --git a/src/database.cpp b/src/database.cpp
new file mode 100644
index 000000000..771d9b962
--- /dev/null
+++ b/src/database.cpp
@@ -0,0 +1,50 @@
+#include "map.h"
+#include "mapsector.h"
+#include "mapblock.h"
+#include "main.h"
+#include "filesys.h"
+#include "voxel.h"
+#include "porting.h"
+#include "mapgen.h"
+#include "nodemetadata.h"
+#include "settings.h"
+#include "log.h"
+#include "profiler.h"
+#include "nodedef.h"
+#include "gamedef.h"
+#include "util/directiontables.h"
+#include "rollback_interface.h"
+
+
+#include "database.h"
+
+static s32 unsignedToSigned(s32 i, s32 max_positive)
+{
+	if(i < max_positive)
+		return i;
+	else
+		return i - 2*max_positive;
+}
+
+// modulo of a negative number does not work consistently in C
+static s64 pythonmodulo(s64 i, s64 mod)
+{
+	if(i >= 0)
+		return i % mod;
+	return mod - ((-i) % mod);
+}
+
+long long Database::getBlockAsInteger(const v3s16 pos) {
+	return (unsigned long long)pos.Z*16777216 +
+		(unsigned long long)pos.Y*4096 + 
+		(unsigned long long)pos.X;
+}
+
+v3s16 Database::getIntegerAsBlock(long long i) {
+	s32 x = unsignedToSigned(pythonmodulo(i, 4096), 2048);
+	i = (i - x) / 4096;
+	s32 y = unsignedToSigned(pythonmodulo(i, 4096), 2048);
+	i = (i - y) / 4096;
+	s32 z = unsignedToSigned(pythonmodulo(i, 4096), 2048);
+	return v3s16(x,y,z);
+}