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//------------------------------------------------------------------------------
// <copyright file="CommandBuilder.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// <owner current="true" primary="true">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
//------------------------------------------------------------------------------
namespace System.Data.Common {
using System.Diagnostics;
using System.Text;
using System.Globalization;
internal class MultipartIdentifier {
private const int MaxParts = 4;
internal const int ServerIndex = 0;
internal const int CatalogIndex = 1;
internal const int SchemaIndex = 2;
internal const int TableIndex = 3;
/*
Left quote strings need to correspond 1 to 1 with the right quote strings
example: "ab" "cd", passed in for the left and the right quote
would set a or b as a starting quote character.
If a is the starting quote char then c would be the ending quote char
otherwise if b is the starting quote char then d would be the ending quote character.
*/
internal static string[] ParseMultipartIdentifier(string name, string leftQuote, string rightQuote, string property, bool ThrowOnEmptyMultipartName) {
return ParseMultipartIdentifier(name, leftQuote, rightQuote,'.', MaxParts, true, property, ThrowOnEmptyMultipartName);
}
private enum MPIState {
MPI_Value,
MPI_ParseNonQuote,
MPI_LookForSeparator,
MPI_LookForNextCharOrSeparator,
MPI_ParseQuote,
MPI_RightQuote,
}
/* Core function for parsing the multipart identifer string.
* paramaters: name - string to parse
* leftquote: set of characters which are valid quoteing characters to initiate a quote
* rightquote: set of characters which are valid to stop a quote, array index's correspond to the the leftquote array.
* separator: separator to use
* limit: number of names to parse out
* removequote:to remove the quotes on the returned string
*/
private static void IncrementStringCount (string name, string[] ary, ref int position, string property) {
++position;
int limit = ary.Length;
if (position >= limit) {
throw ADP.InvalidMultipartNameToManyParts (property, name, limit);
}
ary[position] = string.Empty;
}
private static bool IsWhitespace (char ch) {
return Char.IsWhiteSpace (ch);
}
internal static string[] ParseMultipartIdentifier(string name, string leftQuote, string rightQuote, char separator, int limit, bool removequotes, string property, bool ThrowOnEmptyMultipartName) {
if (limit <= 0) {
throw ADP.InvalidMultipartNameToManyParts (property, name, limit);
}
if (-1 != leftQuote.IndexOf(separator) || -1 != rightQuote.IndexOf(separator) || leftQuote.Length != rightQuote.Length) {
throw ADP.InvalidMultipartNameIncorrectUsageOfQuotes (property, name);
}
string[] parsedNames = new string[limit]; // return string array
int stringCount = 0; // index of current string in the buffer
MPIState state = MPIState.MPI_Value; // Initalize the starting state
StringBuilder sb = new StringBuilder (name.Length); // String buffer to hold the string being currently built, init the string builder so it will never be resized
StringBuilder whitespaceSB = null; // String buffer to hold white space used when parsing nonquoted strings 'a b . c d' = 'a b' and 'c d'
char rightQuoteChar = ' '; // Right quote character to use given the left quote character found.
for (int index = 0; index < name.Length; ++index) {
char testchar = name[index];
switch (state) {
case MPIState.MPI_Value : {
int quoteIndex;
if (IsWhitespace (testchar)) { // Is White Space then skip the whitespace
continue;
}
else
if (testchar == separator) { // If we found a separator, no string was found, initalize the string we are parsing to Empty and the next one to Empty.
// This is NOT a redundent setting of string.Empty it solves the case where we are parsing ".foo" and we should be returning null, null, empty, foo
parsedNames[stringCount] = string.Empty;
IncrementStringCount (name, parsedNames, ref stringCount, property);
}
else
if (-1 != (quoteIndex = leftQuote.IndexOf(testchar))) { // If we are a left quote
rightQuoteChar = rightQuote[quoteIndex]; // record the corresponding right quote for the left quote
sb.Length = 0;
if (!removequotes) {
sb.Append (testchar);
}
state = MPIState.MPI_ParseQuote;
}
else
if (-1 != rightQuote.IndexOf(testchar)) { // If we shouldn't see a right quote
throw ADP.InvalidMultipartNameIncorrectUsageOfQuotes (property, name);
}
else {
sb.Length = 0;
sb.Append (testchar);
state = MPIState.MPI_ParseNonQuote;
}
break;
}
case MPIState.MPI_ParseNonQuote: {
if (testchar == separator) {
parsedNames[stringCount] = sb.ToString (); // set the currently parsed string
IncrementStringCount (name, parsedNames, ref stringCount, property);
state = MPIState.MPI_Value;
}
else // Quotes are not valid inside a non-quoted name
if (-1 != rightQuote.IndexOf (testchar)) {
throw ADP.InvalidMultipartNameIncorrectUsageOfQuotes (property, name);
}
else
if (-1 != leftQuote.IndexOf(testchar)) {
throw ADP.InvalidMultipartNameIncorrectUsageOfQuotes (property, name);
}
else
if (IsWhitespace (testchar)) { // If it is Whitespace
parsedNames[stringCount] = sb.ToString (); // Set the currently parsed string
if (null == whitespaceSB) {
whitespaceSB = new StringBuilder ();
}
whitespaceSB.Length = 0;
whitespaceSB.Append (testchar); // start to record the white space, if we are parsing a name like "foo bar" we should return "foo bar"
state = MPIState.MPI_LookForNextCharOrSeparator;
}
else {
sb.Append (testchar);
}
break;
}
case MPIState.MPI_LookForNextCharOrSeparator : {
if (!IsWhitespace (testchar)) { // If it is not whitespace
if (testchar == separator) {
IncrementStringCount (name, parsedNames, ref stringCount, property);
state = MPIState.MPI_Value;
}
else { // If its not a separator and not whitespace
sb.Append (whitespaceSB);
sb.Append (testchar);
parsedNames[stringCount] = sb.ToString (); // Need to set the name here in case the string ends here.
state = MPIState.MPI_ParseNonQuote;
}
}
else {
whitespaceSB.Append (testchar);
}
break;
}
case MPIState.MPI_ParseQuote: {
if (testchar == rightQuoteChar) { // if se are on a right quote see if we are escapeing the right quote or ending the quoted string
if (!removequotes) {
sb.Append (testchar);
}
state = MPIState.MPI_RightQuote;
}
else {
sb.Append (testchar); // Append what we are currently parsing
}
break;
}
case MPIState.MPI_RightQuote : {
if (testchar == rightQuoteChar) { // If the next char is a another right quote then we were escapeing the right quote
sb.Append (testchar);
state = MPIState.MPI_ParseQuote;
}
else
if (testchar == separator) { // If its a separator then record what we've parsed
parsedNames[stringCount] = sb.ToString ();
IncrementStringCount (name, parsedNames, ref stringCount, property);
state = MPIState.MPI_Value;
}
else
if (!IsWhitespace (testchar)) { // If it is not white space we got problems
throw ADP.InvalidMultipartNameIncorrectUsageOfQuotes (property, name);
}
else { // It is a whitespace character so the following char should be whitespace, separator, or end of string anything else is bad
parsedNames[stringCount] = sb.ToString ();
state = MPIState.MPI_LookForSeparator;
}
break;
}
case MPIState.MPI_LookForSeparator : {
if (!IsWhitespace (testchar)) { // If it is not whitespace
if (testchar == separator) { // If it is a separator
IncrementStringCount (name, parsedNames, ref stringCount, property);
state = MPIState.MPI_Value;
}
else { // Othewise not a separator
throw ADP.InvalidMultipartNameIncorrectUsageOfQuotes (property, name);
}
}
break;
}
}
}
// Resolve final states after parsing the string
switch (state) {
case MPIState.MPI_Value : // These states require no extra action
case MPIState.MPI_LookForSeparator :
case MPIState.MPI_LookForNextCharOrSeparator :
break;
case MPIState.MPI_ParseNonQuote: // Dump what ever was parsed
case MPIState.MPI_RightQuote :
parsedNames[stringCount] = sb.ToString ();
break;
case MPIState.MPI_ParseQuote: // Invalid Ending States
default:
throw ADP.InvalidMultipartNameIncorrectUsageOfQuotes (property, name);
}
if (parsedNames[0] == null) {
if (ThrowOnEmptyMultipartName) {
throw ADP.InvalidMultipartName (property, name); // Name is entirely made up of whitespace
}
}
else {
// Shuffle the parsed name, from left justification to right justification, ie [a][b][null][null] goes to [null][null][a][b]
int offset = limit - stringCount - 1;
if (offset > 0) {
for (int x = limit - 1; x >= offset; --x) {
parsedNames[x] = parsedNames[x - offset];
parsedNames[x - offset] = null;
}
}
}
return parsedNames;
}
}
}
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