// // This method attempts reading quoted-string formatted data when the bounding quotes were omitted. // This is common for e-mail display-names. // // Precondition: The index must be within the bounds of the data string. // // Return value: // - The index of the special delimiter provided. // e.g. In ([email protected], billy box [email protected]), starting at index=19 (x) returns index=9 (,). // - -1 if the terminating character was not found. // e.g. In (my name username@domain), starting at index=5 (e) returns index=-1. // // A FormatException will be thrown or false is returned if: // - A non-escaped character is encountered that is not valid in a quoted string. This includes double quotes. // - A Unicode character is encountered and Unicode has not been allowed. // internal static bool TryReadReverseUnQuoted(string data, int index, bool permitUnicode, bool expectCommaDelimiter, out int outIndex, bool throwExceptionIfFail) { Debug.Assert(0 <= index && index < data.Length, "Index out of range: " + index + ", " + data.Length); do { // Check for valid whitespace if (!WhitespaceReader.TryReadFwsReverse(data, index, out index, throwExceptionIfFail)) { outIndex = default; return(false); } if (index < 0) { break; } // Check for escaped characters if (!QuotedPairReader.TryCountQuotedChars(data, index, permitUnicode, out int quotedCharCount, throwExceptionIfFail)) { outIndex = default; return(false); } if (quotedCharCount > 0) { index -= quotedCharCount; } // Check for the terminating char else if (expectCommaDelimiter && data[index] == MailBnfHelper.Comma) { break; } // Check invalid characters else if (!IsValidQtext(permitUnicode, data[index])) { if (throwExceptionIfFail) { throw new FormatException(SR.Format(SR.MailHeaderFieldInvalidCharacter, data[index])); } else { outIndex = default; return(false); } } // Valid char else { index--; } }while (index >= 0); outIndex = index; return(true); }
// // This method reads a standard quoted string. Departing from the RFC, Unicode is permitted for display-name. // // Preconditions: // - Index must be within the bounds of the data string. // - The char at the given index is the initial quote. (data[index] == Quote) // // Return value: The next index past the terminating-quote (data[index + 1] == Quote). // e.g. In (bob "user name"@domain), starting at index=14 (") returns index=3 (space). // // A FormatException will be thrown or false is returned if: // - A non-escaped character is encountered that is not valid in a quoted string. // - A Unicode character is encountered and Unicode has not been allowed. // - The final double quote is not found. // internal static bool TryReadReverseQuoted(string data, int index, bool permitUnicode, out int outIndex, bool throwExceptionIfFail) { Debug.Assert(0 <= index && index < data.Length, "Index out of range: " + index + ", " + data.Length); // Check for the first bounding quote Debug.Assert(data[index] == MailBnfHelper.Quote, "Initial char at index " + index + " was not a quote."); // Skip the bounding quote index--; do { // Check for valid whitespace if (!WhitespaceReader.TryReadFwsReverse(data, index, out index, throwExceptionIfFail)) { outIndex = default; return(false); } if (index < 0) { break; } // Check for escaped characters if (!QuotedPairReader.TryCountQuotedChars(data, index, permitUnicode, out int quotedCharCount, throwExceptionIfFail)) { outIndex = default; return(false); } if (quotedCharCount > 0) { // Skip quoted pairs index -= quotedCharCount; } // Check for the terminating quote else if (data[index] == MailBnfHelper.Quote) { // Skip the final bounding quote outIndex = index - 1; return(true); } // Check invalid characters else if (!IsValidQtext(permitUnicode, data[index])) { if (throwExceptionIfFail) { throw new FormatException(SR.Format(SR.MailHeaderFieldInvalidCharacter, data[index])); } else { outIndex = default; return(false); } } // Valid char else { index--; } }while (index >= 0); if (throwExceptionIfFail) { // We started with a quote, but did not end with one throw new FormatException(SR.Format(SR.MailHeaderFieldInvalidCharacter, MailBnfHelper.Quote)); } else { outIndex = default; return(false); } }
// // Parse a single MailAddress, potentially from a list. // // Preconditions: // - Index must be within the bounds of the data string. // - The data string must not be null or empty // // Postconditions: // - Returns a valid MailAddress object parsed from the string // - For a single MailAddress index is set to -1 // - For a list data[index] is the comma separator or -1 if the end of the data string was reached. // // Throws a FormatException or false is returned if any part of the MailAddress is invalid. private static bool TryParseAddress(string data, bool expectMultipleAddresses, ref int index, out ParseAddressInfo parseAddressInfo, bool throwExceptionIfFail) { Debug.Assert(!string.IsNullOrEmpty(data)); Debug.Assert(index >= 0 && index < data.Length, "Index out of range: " + index + ", " + data.Length); // Parsed components to be assembled as a MailAddress later string?displayName; // Skip comments and whitespace if (!TryReadCfwsAndThrowIfIncomplete(data, index, out index, throwExceptionIfFail)) { parseAddressInfo = default; return(false); } // Do we expect angle brackets around the address? // e.g. ("display name" <user@domain>) bool expectAngleBracket = false; if (data[index] == MailBnfHelper.EndAngleBracket) { expectAngleBracket = true; index--; } if (!TryParseDomain(data, ref index, out string?domain, throwExceptionIfFail)) { parseAddressInfo = default; return(false); } // The next character after the domain must be the '@' symbol if (data[index] != MailBnfHelper.At) { if (throwExceptionIfFail) { throw new FormatException(SR.MailAddressInvalidFormat); } else { parseAddressInfo = default; return(false); } } // Skip the '@' symbol index--; if (!TryParseLocalPart(data, ref index, expectAngleBracket, expectMultipleAddresses, out string?localPart, throwExceptionIfFail)) { parseAddressInfo = default; return(false); } // Check for a matching angle bracket around the address if (expectAngleBracket) { if (index >= 0 && data[index] == MailBnfHelper.StartAngleBracket) { index--; // Skip the angle bracket // Skip whitespace, but leave comments, as they may be part of the display name. if (!WhitespaceReader.TryReadFwsReverse(data, index, out index, throwExceptionIfFail)) { parseAddressInfo = default; return(false); } } else { // Mismatched angle brackets if (throwExceptionIfFail) { throw new FormatException(SR.Format(SR.MailHeaderFieldInvalidCharacter, (index >= 0 ? data[index] : MailBnfHelper.EndAngleBracket))); } else { parseAddressInfo = default; return(false); } } } // Is there anything left to parse? // There could still be a display name or another address if (index >= 0 && !(expectMultipleAddresses && data[index] == MailBnfHelper.Comma)) { if (!TryParseDisplayName(data, ref index, expectMultipleAddresses, out displayName, throwExceptionIfFail)) { parseAddressInfo = default; return(false); } } else { displayName = string.Empty; } parseAddressInfo = new ParseAddressInfo(displayName, localPart, domain); return(true); }
// // Reads a domain literal in reverse // // Preconditions: // - Index must be within the bounds of the data string. // - The char at the given index is the initial bracket. (data[index] == EndSquareBracket) // // Return value: // - The next index past the terminating bracket (data[index + 1] == StartSquareBracket). // e.g. In (user@[domain]), starting at index=12 (]) returns index=4 (@). // // A FormatException will be thrown or false is returned if: // - A non-escaped character is encountered that is not valid in a domain literal, including Unicode. // - The final bracket is not found. // internal static bool TryReadReverse(string data, int index, out int outIndex, bool throwExceptionIfFail) { Debug.Assert(0 <= index && index < data.Length, "index was outside the bounds of the string: " + index); Debug.Assert(data[index] == MailBnfHelper.EndSquareBracket, "data did not end with a square bracket"); // Skip the end bracket index--; do { // Check for valid whitespace if (!WhitespaceReader.TryReadFwsReverse(data, index, out index, throwExceptionIfFail)) { outIndex = default; return(false); } if (index < 0) { break; } // Check for escaped characters if (!QuotedPairReader.TryCountQuotedChars(data, index, false, out int quotedCharCount, throwExceptionIfFail)) { outIndex = default; return(false); } if (quotedCharCount > 0) { // Skip quoted pairs index -= quotedCharCount; } // Check for the terminating bracket else if (data[index] == MailBnfHelper.StartSquareBracket) { // We're done parsing outIndex = index - 1; return(true); } // Check for invalid characters else if (data[index] > MailBnfHelper.Ascii7bitMaxValue || !MailBnfHelper.Dtext[data[index]]) { if (throwExceptionIfFail) { throw new FormatException(SR.Format(SR.MailHeaderFieldInvalidCharacter, data[index])); } else { outIndex = default; return(false); } } // Valid char else { index--; } }while (index >= 0); if (throwExceptionIfFail) { // We didn't find a matching '[', throw. throw new FormatException(SR.Format(SR.MailHeaderFieldInvalidCharacter, MailBnfHelper.EndSquareBracket)); } else { outIndex = default; return(false); } }