/// <summary>
/// Copy a previously-encoded UTF-8 string value into this byte array.
/// A call to this method must be preceded by a call to "encodeTag"
/// or "encodeTagArray". The caller must ensure the byte array is a
/// valid UTF-8 encoded string; no checking is performed.
/// </summary>
/// <param name="value">The byte array containing a UTF-8 string
/// to be included in the output message.</param>
/// <param name="offset">The offset in <paramref name="offset"/>
/// where the encoded UTF-8 string begins.</param>
/// <param name="length">The length of the UTF-8 encoded stirng,
/// in bytes, to be written to the output message.</param>
/// <returns>This builder.</returns>
public BFlatBuilder encode(byte[] value, int offset, int length)
{
Leb128.encodeUnsigned(this, (uint)length);
Array.Copy(value, offset, data, position, length);
position += length;
return(this);
}
// Internal version just uses a "byte" as the first parameter.
internal BFlatBuilder encodeTag(byte type, String tagName)
{
if (tagName.Length == 0)
{
throw new BFlatException("Zero length tags are not allowed.");
}
uint tagLen = (uint)tagName.Length;
if (tagLen < 8)
{
// see if fit the tag len into the byte0
int byte0 = position++;
uint actual = encodeString(tagName);
if (actual < 8)
{
data[byte0] = (byte)(type | actual);
}
else
{
// since the tag <8 characters we know that the # of bytes
// it will fit in is representable with a one byte leb128
data[byte0] = (byte)type;
Array.Copy(data, byte0 + 1, data, byte0 + 2, actual);
data[byte0 + 1] = (byte)actual;
++position;
}
}
else
{
data[position++] = (byte)type;
int start = position;
int leblength = Leb128.encodeUnsigned(this, tagLen);
uint actual = encodeString(tagName);
if (actual != tagLen)
{
int end = position;
position = start;
int actual_leblength = Leb128.encodeUnsigned(this, actual);
// do we need to reserialize the data?
if (actual_leblength != leblength)
{
encodeString(tagName);
}
else
{
position = end;
}
}
}
return(this);
}
/// <summary>
/// Encode a string value into this byte array. A call to this method
/// must be preceded by a call to "encodeTag" or "encodeTagArray."
/// </summary>
/// <param name="value">The value to encode into this array.</param>
/// <returns>This builder.</returns>
public BFlatBuilder encode(String value)
{
int charcount = value.Length;
int start = position;
int leblength = Leb128.encodeUnsigned(this, (uint)charcount);
uint bytecount = encodeString(value);
int end = position;
if (bytecount != charcount) // non ascii
{
position = start;
int actual_leblength = Leb128.encodeUnsigned(this, bytecount);
if (actual_leblength != leblength)
{
//reserialize the string
encodeString(value);
}
else
{
position = end;
}
}
return(this);
}
// Internal version of encodeTag takes a byte as the first parameter.
internal BFlatBuilder encodeTag(byte type, byte[] tagName)
{
if (tagName.Length == 0)
{
throw new BFlatException("Zero length tags are not allowed.");
}
int tagLen = tagName.Length;
if (tagLen < 8)
{
// fit the tag len into the byte0
data[position++] = (byte)((int)type | tagLen);
Array.Copy(tagName, 0, data, position, tagLen);
position += tagLen;
}
else
{
data[position++] = (byte)type;
Leb128.encodeUnsigned(this, (uint)tagLen);
Array.Copy(tagName, 0, data, position, tagLen);
position += tagLen;
}
return(this);
}
BFlatValue parseNext()
{
if (position >= _end)
{
return(null);
}
BFlatValue value = (_current != null && _current.isReuse())
? _current.reset(data) : new BFlatValue(data);
byte byte0 = data[position++];
byte type = (byte)(byte0 & BFlatEncoding.TypeMask);
bool isArray = (byte0 & BFlatEncoding.ArrayMask) != 0;
int tagLength = byte0 & BFlatEncoding.LengthMask;
int tagStart = position;
if (tagLength == 0)
{
tagLength = (int)(Leb128.decodeUnsigned(this));
if (tagLength == 0)
{
throw new BFlatException("zero-length tag", position);
}
tagStart = position;
}
value.setTag(tagStart, tagLength);
position += tagLength;
int dataStart = position;
int elementCount = 1;
if (isArray)
{
elementCount = (int)(Leb128.decodeUnsigned(this));
dataStart = position;
}
value.setData(position, byte0, elementCount);
// for variable length types we have to parse the array contents
switch ((BFlatEncoding.Type)type)
{
case BFlatEncoding.Type.String:
case BFlatEncoding.Type.Binary:
for (int i = 0; i < elementCount; ++i)
{
int length = (int)(Leb128.decodeUnsigned(this));
value.setStringOffsetAndLen(i, position, length);
position += length;
}
break;
case BFlatEncoding.Type.Leb128:
for (int i = 0; i < elementCount; ++i)
{
long leb128 = Leb128.decodeSigned(this);
value.setLeb128Value(i, leb128);
}
break;
case BFlatEncoding.Type.Int8:
position += elementCount;
break;
case BFlatEncoding.Type.Int16:
position += elementCount * 2;
break;
case BFlatEncoding.Type.Int32:
position += elementCount * 4;
break;
case BFlatEncoding.Type.Int64:
case BFlatEncoding.Type.Double:
case BFlatEncoding.Type.Datetime:
position += elementCount * 8;
break;
case BFlatEncoding.Type.Null:
break;
default:
throw new BFlatException("unknown value type", position);
}
return(value);
}
encodeTagArray(BFlatEncoding.Type type, String tagName, int count)
{
encodeTag((byte)((byte)type | BFlatEncoding.ArrayMask), tagName);
Leb128.encodeUnsigned(this, (uint)count);
return(this);
}
