/// <summary>
/// Reads a BsonType from the reader.
/// </summary>
/// <typeparam name="TValue">The type of the BsonTrie values.</typeparam>
/// <param name="bsonTrie">An optional trie to search for a value that matches the next element name.</param>
/// <param name="found">Set to true if a matching value was found in the trie.</param>
/// <param name="value">Set to the matching value found in the trie or null if no matching value was found.</param>
/// <returns>A BsonType.</returns>
public override BsonType ReadBsonType <TValue>(BsonTrie <TValue> bsonTrie, out bool found, out TValue value)
{
if (Disposed)
{
ThrowObjectDisposedException();
}
found = false;
value = default(TValue);
if (State == BsonReaderState.Initial || State == BsonReaderState.ScopeDocument)
{
// there is an implied type of Document for the top level and for scope documents
CurrentBsonType = BsonType.Document;
State = BsonReaderState.Value;
return(CurrentBsonType);
}
if (State != BsonReaderState.Type)
{
ThrowInvalidState("ReadBsonType", BsonReaderState.Type);
}
switch (_context.ContextType)
{
case ContextType.Array:
_currentValue = _context.GetNextValue();
if (_currentValue == null)
{
State = BsonReaderState.EndOfArray;
return(BsonType.EndOfDocument);
}
State = BsonReaderState.Value;
break;
case ContextType.Document:
var currentElement = _context.GetNextElement();
if (currentElement == null)
{
State = BsonReaderState.EndOfDocument;
return(BsonType.EndOfDocument);
}
if (bsonTrie != null)
{
found = bsonTrie.TryGetValue(currentElement.Name, out value);
}
CurrentName = currentElement.Name;
_currentValue = currentElement.Value;
State = BsonReaderState.Name;
break;
default:
throw new BsonInternalException("Invalid ContextType.");
}
CurrentBsonType = _currentValue.BsonType;
return(CurrentBsonType);
}
/// <summary>
/// Reads an element name.
/// </summary>
/// <typeparam name="TValue">The type of the BsonTrie values.</typeparam>
/// <param name="bsonTrie">An optional BsonTrie to use during decoding.</param>
/// <param name="found">Set to true if the string was found in the trie.</param>
/// <param name="value">Set to the value found in the trie; otherwise, null.</param>
/// <returns>A string.</returns>
public string ReadName <TValue>(BsonTrie <TValue> bsonTrie, out bool found, out TValue value)
{
ThrowIfDisposed();
found = false;
value = default(TValue);
if (bsonTrie == null)
{
return(ReadCString(Utf8Encodings.Strict)); // always use strict encoding for names
}
var savedPosition = _byteBuffer.Position;
var bsonTrieNode = bsonTrie.Root;
while (true)
{
var keyByte = _byteBuffer.ReadByte();
if (keyByte == 0)
{
if (bsonTrieNode.HasValue)
{
found = true;
value = bsonTrieNode.Value;
return(bsonTrieNode.ElementName);
}
else
{
var nullPosition = _byteBuffer.Position - 1;
_byteBuffer.Position = savedPosition;
return(ReadCString(Utf8Encodings.Strict, nullPosition)); // always use strict encoding for names
}
}
bsonTrieNode = bsonTrieNode.GetChild(keyByte);
if (bsonTrieNode == null)
{
var nullPosition = _byteBuffer.FindNullByte(); // starting from where we got so far
_byteBuffer.Position = savedPosition;
return(ReadCString(Utf8Encodings.Strict, nullPosition)); // always use strict encoding for names
}
}
}
/// <summary>
/// Reads a BsonType from the reader.
/// </summary>
/// <typeparam name="TValue">The type of the BsonTrie values.</typeparam>
/// <param name="bsonTrie">An optional trie to search for a value that matches the next element name.</param>
/// <param name="found">Set to true if a matching value was found in the trie.</param>
/// <param name="value">Set to the matching value found in the trie or null if no matching value was found.</param>
/// <returns>A BsonType.</returns>
public override BsonType ReadBsonType <TValue>(BsonTrie <TValue> bsonTrie, out bool found, out TValue value)
{
if (Disposed)
{
ThrowObjectDisposedException();
}
found = false;
value = default(TValue);
if (State == BsonReaderState.Initial || State == BsonReaderState.Done || State == BsonReaderState.ScopeDocument)
{
// there is an implied type of Document for the top level and for scope documents
CurrentBsonType = BsonType.Document;
State = BsonReaderState.Value;
return(CurrentBsonType);
}
if (State != BsonReaderState.Type)
{
ThrowInvalidState("ReadBsonType", BsonReaderState.Type);
}
CurrentBsonType = _buffer.ReadBsonType();
if (CurrentBsonType == BsonType.EndOfDocument)
{
switch (_context.ContextType)
{
case ContextType.Array:
State = BsonReaderState.EndOfArray;
return(BsonType.EndOfDocument);
case ContextType.Document:
case ContextType.ScopeDocument:
State = BsonReaderState.EndOfDocument;
return(BsonType.EndOfDocument);
default:
var message = string.Format("BsonType EndOfDocument is not valid when ContextType is {0}.", _context.ContextType);
throw new FileFormatException(message);
}
}
else
{
switch (_context.ContextType)
{
case ContextType.Array:
_buffer.SkipCString(); // ignore array element names
State = BsonReaderState.Value;
break;
case ContextType.Document:
case ContextType.ScopeDocument:
CurrentName = _buffer.ReadCString(bsonTrie, out found, out value);
State = BsonReaderState.Name;
break;
default:
throw new BsonInternalException("Unexpected ContextType.");
}
return(CurrentBsonType);
}
}
/// <summary>
/// Reads a BSON CString from the reader (a null terminated string).
/// </summary>
/// <typeparam name="TValue">The type of the BsonTrie values.</typeparam>
/// <param name="bsonTrie">An optional BsonTrie to use during decoding.</param>
/// <param name="found">Set to true if the string was found in the trie.</param>
/// <param name="value">Set to the value found in the trie; otherwise, null.</param>
/// <returns>A string.</returns>
public string ReadCString <TValue>(BsonTrie <TValue> bsonTrie, out bool found, out TValue value)
{
if (_disposed)
{
throw new ObjectDisposedException("BsonBuffer");
}
found = false;
value = default(TValue);
// optimize for the case where the null terminator is on the same chunk
int partialCount;
if (_chunkIndex < _chunks.Count - 1)
{
partialCount = __chunkSize - _chunkOffset; // remaining part of any chunk but the last
}
else
{
partialCount = _length - _position; // populated part of last chunk
}
var bsonTrieNode = bsonTrie != null ? bsonTrie.Root : null;
var index = IndexOfNull(_chunk, _chunkOffset, partialCount, ref bsonTrieNode);
if (index != -1)
{
var stringLength = index - _chunkOffset;
string cstring;
if (bsonTrieNode != null && bsonTrieNode.HasValue)
{
cstring = bsonTrieNode.ElementName;
value = bsonTrieNode.Value;
found = true;
}
else
{
cstring = DecodeUtf8String(_chunk, _chunkOffset, stringLength);
}
Position += stringLength + 1;
return(cstring);
}
// the null terminator is not on the same chunk so keep looking starting with the next chunk
var localChunkIndex = _chunkIndex + 1;
var localPosition = localChunkIndex * __chunkSize;
while (localPosition < _length)
{
var localChunk = _chunks[localChunkIndex];
if (localChunkIndex < _chunks.Count - 1)
{
partialCount = __chunkSize; // all of any chunk but the last
}
else
{
partialCount = _length - localPosition; // populated part of last chunk
}
index = IndexOfNull(localChunk, 0, partialCount, ref bsonTrieNode);
if (index != -1)
{
localPosition += index;
var stringLength = localPosition - _position;
string cstring;
if (bsonTrieNode != null && bsonTrieNode.HasValue)
{
cstring = bsonTrieNode.ElementName;
value = bsonTrieNode.Value;
found = true;
Position += stringLength + 1;
}
else
{
cstring = __utf8Encoding.GetString(ReadBytes(stringLength)); // ReadBytes advances over string
Position += 1; // skip over null byte at end
}
return(cstring);
}
localChunkIndex++;
localPosition += __chunkSize;
}
throw new FileFormatException("String is missing null terminator.");
}
/// <summary> /// Reads a BsonType from the reader. /// </summary> /// <typeparam name="TValue">The type of the BsonTrie values.</typeparam> /// <param name="bsonTrie">An optional trie to search for a value that matches the next element name.</param> /// <param name="found">Set to true if a matching value was found in the trie.</param> /// <param name="value">Set to the matching value found in the trie or null if no matching value was found.</param> /// <returns>A BsonType.</returns> public abstract BsonType ReadBsonType <TValue>(BsonTrie <TValue> bsonTrie, out bool found, out TValue value);
