/// <summary> /// Enumerates all entries. /// </summary> /// <param name="filter">Filter controlling which entries are returned</param> /// <returns>An enumeration of entries matching the filter.</returns> public IEnumerable <MasterFileTableEntry> GetEntries(EntryStates filter) { foreach (var record in _mft.Records) { EntryStates state; if ((record.Flags & FileRecordFlags.InUse) != 0) { state = EntryStates.InUse; } else { state = EntryStates.NotInUse; } if ((state & filter) != 0) { yield return(new MasterFileTableEntry(_context, record)); } } }
/// <summary> /// Enumerates all entries. /// </summary> /// <param name="filter">Filter controlling which entries are returned</param> /// <returns>An enumeration of entries matching the filter.</returns> public IEnumerable<MasterFileTableEntry> GetEntries(EntryStates filter) { foreach (var record in _mft.Records) { EntryStates state; if ((record.Flags & FileRecordFlags.InUse) != 0) { state = EntryStates.InUse; } else { state = EntryStates.NotInUse; } if ((state & filter) != 0) { yield return new MasterFileTableEntry(_context, record); } } }
public BibTeXEntry GetBibTeXEntry(ICollection <BibTeXToken> tokens) { //TODO: Need to reduce complexity of this function // // Algorithm to implement the logic for the parsing a set of tokens // // * Algorithm to parse a set of tokens // * 1. check for minimum no of tokens. // Minimum tokens: // @ proceedings { DBLP:conf/vldb/2005 , } // * 2. Retrieve name and key from the list. Check for sync characters like '{' before and after ',' key. // * 3. Build all properties. Check for sync character also. Like '=', ',' // // The function follows DFA (Deterministic Finite State Automate): // It reads one value at a time and moves to expected state. In the new state if the current // symbol is not expected then it throws error. List <BibTeXToken> allTokens = new List <BibTeXToken>(tokens); BibTeXEntry bibtex = new BibTeXEntry(); #region Check for empty values, Minimum size // Check for length here... must be at least 4 // Must be atleast 4 tokens. For Example: @ typeName { } if (allTokens.Count < 4) { throw new BibTeXParserException(Properties.Resources.BIBTEXPARSER_NOT_WELL_FORMED, allTokens[0].LineNumber, allTokens[0].ColumnNumber, allTokens[0].Value); } #endregion #region Retrieve Name and Key. Check for sync tokens also // First token must be '@' if (!AreEqual(allTokens[0].Value, BibTeXHelper.BT_ENTRY_AT)) { throw new BibTeXParserException("'@' expected", allTokens[0].LineNumber, allTokens[0].ColumnNumber, allTokens[0].Value); } // Check for valid entry name if (!BibTeXHelper.IsValidEntyName(allTokens[1].Value)) { throw new BibTeXParserException("Invalid entry name", allTokens[1].LineNumber, allTokens[1].ColumnNumber, allTokens[1].Value); } bibtex.Name = allTokens[1].Value; // third token must be start of the entry '{' if (!AreEqual(allTokens[2].Value, BibTeXHelper.BT_ENTRY_LEFT_BRACE) && !AreEqual(allTokens[2].Value, BibTeXHelper.BT_ENTRY_LEFT_PARENTHESIS)) { throw new BibTeXParserException("'{' or '(' expected", allTokens[2].LineNumber, allTokens[2].ColumnNumber, allTokens[2].Value); } // Check for valid key if (!BibTeXHelper.IsValidKey(allTokens[3].Value)) { throw new BibTeXParserException("Invalid key", allTokens[3].LineNumber, allTokens[3].ColumnNumber, allTokens[3].Value); } bibtex.Key = allTokens[3].Value; // Last token must be '}' : TODO: Do this check at last. //if (!this.AreEqual(allTokens[allTokens.Count - 1].Value, BibTeXHelper.BT_ENTRY_RIGHT_BRACE)) //{ // throw new BibTeXParserException("'}' expected", allTokens[allTokens.Count - 1].LineNumber, // allTokens[allTokens.Count - 1].ColumnNumber, allTokens[allTokens.Count - 1].Value); //} #endregion #region Check whether any key-value pair is present? if (allTokens.Count == 4) { if (AreEqual(allTokens[2].Value, BibTeXHelper.BT_ENTRY_LEFT_PARENTHESIS)) { throw new BibTeXParserException("')' expected", allTokens[3].LineNumber, allTokens[3].ColumnNumber + allTokens[3].Value.Length, String.Empty); } else { throw new BibTeXParserException("'}' expected", allTokens[3].LineNumber, allTokens[3].ColumnNumber + allTokens[3].Value.Length, String.Empty); } } #endregion #region Process Properties. Operating liner way (one symbol at a time) allows easy error populating. List <BibTeXToken> .Enumerator enumerator = allTokens.GetEnumerator(); // skip first four entries which are already processed (Name and Key). int i; for (i = 0; i < 4; i++) { enumerator.MoveNext(); } i--; EntryStates nextExpectedSymbol = EntryStates.CommaSign; //ValueEncapsulator encapsulator = ValueEncapsulator.None; ComplexValueStates nextTokenComplexVlaue = ComplexValueStates.Exited; string key = string.Empty; string value = string.Empty; bool skipMoveNext = false; System.Text.RegularExpressions.Regex nonAlphaNumericPattern = new System.Text.RegularExpressions.Regex("[^a-zA-Z0-9]"); // Format of a particular key-value pair // , title = { value } while (true) { if (!skipMoveNext) { enumerator.MoveNext(); // break; // should not be called in any case, // as exiting from the loop is handled in following 'if' i++; } else { skipMoveNext = false; } // Following 'if' ensures that the loop will break, before enumerator.MoveNext() returns false if (i == allTokens.Count - 1) { if ((AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_RIGHT_BRACE) && AreEqual(allTokens[2].Value, BibTeXHelper.BT_ENTRY_LEFT_BRACE) ) || (AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_RIGHT_PARENTHESIS)) && AreEqual(allTokens[2].Value, BibTeXHelper.BT_ENTRY_LEFT_PARENTHESIS) ) { // probably the last element so exist from the loop // but before exiting, is there any pending complexValue creation running ? if (nextTokenComplexVlaue == ComplexValueStates.ConcatenationOrComma && !String.IsNullOrEmpty(key)) { bibtex.Properties[key] = value; nextExpectedSymbol = EntryStates.CommaSign; // graceful termination ;) break; } else if (nextTokenComplexVlaue == ComplexValueStates.Exited) { //nextExpectedSymbol = EntryStates.CommaSign; // graceful termination ;) break; } else { throw new BibTeXParserException(Properties.Resources.BIBTEXTPARSER_UNEXPECTED_TOKEN, enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } } else { if (AreEqual(allTokens[2].Value, BibTeXHelper.BT_ENTRY_LEFT_PARENTHESIS)) { throw new BibTeXParserException("')' expected", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } else { throw new BibTeXParserException("'}' expected", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } } } switch (nextExpectedSymbol) { case EntryStates.CommaSign: if (!AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_COMMA)) { throw new BibTeXParserException("',' expected", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } nextExpectedSymbol = EntryStates.KeyName; break; case EntryStates.KeyName: if (!BibTeXHelper.IsValidPropertyName(enumerator.Current.Value)) { throw new BibTeXParserException("Invalid property name", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } // Key name is always converted to lower case. Hence, 'EDITOR', 'EDItor' and 'editor' are same. key = enumerator.Current.Value.ToLowerInvariant(); nextExpectedSymbol = EntryStates.EqualSign; break; case EntryStates.EqualSign: if (!AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_EQUAL)) { throw new BibTeXParserException("'=' expected", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } nextExpectedSymbol = EntryStates.OpeningValue; break; case EntryStates.OpeningValue: if (AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_LEFT_BRACE)) { //encapsulator = ValueEncapsulator.LeftBrace; nextExpectedSymbol = EntryStates.ValueSimple; //skipMoveNext = true; } else if (AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_QUOTATION)) { //encapsulator = ValueEncapsulator.Quotation; nextExpectedSymbol = EntryStates.ValueComplex; skipMoveNext = true; } else if (this.symbolTable.ContainsKey(enumerator.Current.Value)) { nextExpectedSymbol = EntryStates.ValueComplex; skipMoveNext = true; // skip as we need to process the token ;) } else if (!nonAlphaNumericPattern.IsMatch(enumerator.Current.Value)) { // Hmm... the value is - // 1. not encapsulated with braces or quotation mark // 2. is not defined as symbol name // 3. and alphanumeric. // Hence, accept it as value itself. value = enumerator.Current.Value; bibtex.Properties[key] = value; key = string.Empty; value = string.Empty; nextExpectedSymbol = EntryStates.CommaSign; } else { throw new BibTeXParserException("'{' or '\"' or symbol name expected", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } break; case EntryStates.ValueSimple: if (AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_RIGHT_BRACE)) { // if a pair is like --> title={} <<- the value must be empty value = string.Empty; skipMoveNext = true; } else { value = enumerator.Current.Value; } nextExpectedSymbol = EntryStates.ClosingValueBrace; break; case EntryStates.ValueComplex: #region Process Complex Vlaues: may be formed of symbol names, concatenation operatios, etc; if (nextTokenComplexVlaue == ComplexValueStates.Exited) { nextTokenComplexVlaue = ComplexValueStates.Started; } switch (nextTokenComplexVlaue) { case ComplexValueStates.Started: // First symbol can only be a variable name or quotation mark if (this.symbolTable.ContainsKey(enumerator.Current.Value)) { value += this.symbolTable[enumerator.Current.Value]; nextTokenComplexVlaue = ComplexValueStates.ConcatenationOrComma; } else if (AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_QUOTATION)) { nextTokenComplexVlaue = ComplexValueStates.Value; } else { throw new BibTeXParserException("'\"' or symbol name expected", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } break; case ComplexValueStates.VariableName: break; case ComplexValueStates.ConcatenationOrComma: if (AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_CONCATENATION)) { // move back to started, i.e. it may be variableName or QUOTATION mark nextTokenComplexVlaue = ComplexValueStates.Started; skipMoveNext = false; } else if (AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_COMMA)) { // if next is ',' then value is built // 1. Save the key-value ; and reset key/value // 2. exit from inner switch // 3. move next in the outer switch, // 4. skip the call to enumerator.MoveNext() as the comma is already fetched but yet to be processed bibtex.Properties[key] = value; key = value = string.Empty; nextTokenComplexVlaue = ComplexValueStates.Exited; nextExpectedSymbol = EntryStates.CommaSign; skipMoveNext = true; } else { throw new BibTeXParserException("',' expected.", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } break; case ComplexValueStates.Concatenation: nextTokenComplexVlaue = ComplexValueStates.VariableName; break; case ComplexValueStates.OpeningQuotation: nextTokenComplexVlaue = ComplexValueStates.Value; break; case ComplexValueStates.Value: if (AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_QUOTATION)) { // if a pair is like --> title="" <<- the value must be empty value += string.Empty; skipMoveNext = true; } else { value += enumerator.Current.Value; } nextTokenComplexVlaue = ComplexValueStates.ClosingQuotation; break; case ComplexValueStates.ClosingQuotation: if (!AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_QUOTATION)) { throw new BibTeXParserException("'}' expected", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } nextTokenComplexVlaue = ComplexValueStates.ConcatenationOrComma; break; case ComplexValueStates.Exited: nextExpectedSymbol = EntryStates.CommaSign; break; default: // This case should not be called in any case throw new BibTeXParserException("Unexpected error"); } #endregion break; case EntryStates.ClosingValueBrace: if (!AreEqual(enumerator.Current.Value, BibTeXHelper.BT_ENTRY_RIGHT_BRACE)) { throw new BibTeXParserException("'}' expected", enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } // So the value is well encapsulated. Add it to the list. and clear key and value. bibtex.Properties[key] = value; key = string.Empty; value = string.Empty; //proceed to the next key-value pair. nextExpectedSymbol = EntryStates.CommaSign; break; default: // This case should not be called any how throw new BibTeXParserException("Unexpected error"); } } if (nextExpectedSymbol != EntryStates.CommaSign && nextExpectedSymbol != EntryStates.KeyName) { throw new BibTeXParserException("Not well formed property value. Last symbol processed: " + enumerator.Current.Value, enumerator.Current.LineNumber, enumerator.Current.ColumnNumber, enumerator.Current.Value); } #endregion return(bibtex); }