/// <summary>
/// If the database contains an entry for "key" return the value,
/// otherwise return null.
/// </summary>
public unsafe byte[] Get(byte[] key, ReadOptions options)
{
IntPtr error;
IntPtr lengthPtr;
var valuePtr = LevelDBInterop.leveldb_get(this.Handle, options.Handle, key, (IntPtr)key.Length, out lengthPtr, out error);
LevelDBException.Check(error);
if (valuePtr == IntPtr.Zero)
{
return(null);
}
try {
var length = (long)lengthPtr;
var value = new byte[length];
var valueNative = (byte *)valuePtr.ToPointer();
for (long i = 0; i < length; ++i)
{
value[i] = valueNative[i];
}
return(value);
} finally {
LevelDBInterop.leveldb_free(valuePtr);
GC.KeepAlive(options);
GC.KeepAlive(this);
}
}
public static void Check(IntPtr error)
{
if (error != IntPtr.Zero)
{
try
{
var message = Marshal.PtrToStringAnsi(error);
throw new LevelDBException(message);
}
finally
{
LevelDBInterop.leveldb_free(error);
}
}
}
/// <summary>
/// DB implementations can export properties about their state
/// via this method. If "property" is a valid property understood by this
/// DB implementation, fills "*value" with its current value and returns
/// true. Otherwise returns false.
///
/// Valid property names include:
///
/// "leveldb.num-files-at-level<N>" - return the number of files at level <N>,
/// where <N> is an ASCII representation of a level number (e.g. "0").
/// "leveldb.stats" - returns a multi-line string that describes statistics
/// about the internal operation of the DB.
/// </summary>
public string PropertyValue(string name)
{
var ptr = LevelDBInterop.leveldb_property_value(this.Handle, name);
if (ptr == IntPtr.Zero)
{
return(null);
}
try {
return(Marshal.PtrToStringAnsi(ptr));
} finally {
LevelDBInterop.leveldb_free(ptr);
GC.KeepAlive(this);
}
}