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Comparing ibx/trunk/fbintf/IBUtils.pas (file contents):
Revision 231 by tony, Mon Apr 16 08:32:21 2018 UTC vs.
Revision 311 by tony, Mon Aug 24 09:32:58 2020 UTC

# Line 47 | Line 47 | interface
47  
48   uses Classes, SysUtils, IB;
49  
50 + type
51 +  TSQLTokens = (
52 +
53 +  {Reserved Words}
54 +
55 +  sqltAdd,
56 +  sqltAdmin,
57 +  sqltAll,
58 +  sqltAlter,
59 +  sqltAnd,
60 +  sqltAny,
61 +  sqltAs,
62 +  sqltAt,
63 +  sqltAvg,
64 +  sqltBegin,
65 +  sqltBetween,
66 +  sqltBigint,
67 +  sqltBit_Length,
68 +  sqltBlob,
69 +  sqltBoolean,
70 +  sqltBoth,
71 +  sqltBy,
72 +  sqltCase,
73 +  sqltCast,
74 +  sqltChar,
75 +  sqltChar_Length,
76 +  sqltCharacter,
77 +  sqltCharacter_Length,
78 +  sqltCheck,
79 +  sqltClose,
80 +  sqltCollate,
81 +  sqltColumn,
82 +  sqltCommit,
83 +  sqltConnect,
84 +  sqltConstraint,
85 +  sqltCorr,
86 +  sqltCount,
87 +  sqltCovar_Pop,
88 +  sqltCovar_Samp,
89 +  sqltCreate,
90 +  sqltCross,
91 +  sqltCurrent,
92 +  sqltCurrent_Connection,
93 +  sqltCurrent_Date,
94 +  sqltCurrent_Role,
95 +  sqltCurrent_Time,
96 +  sqltCurrent_Timestamp,
97 +  sqltCurrent_Transaction,
98 +  sqltCurrent_User,
99 +  sqltCursor,
100 +  sqltDate,
101 +  sqltDay,
102 +  sqltDec,
103 +  sqltDecimal,
104 +  sqltDeclare,
105 +  sqltDefault,
106 +  sqltDelete,
107 +  sqltDeleting,
108 +  sqltDeterministic,
109 +  sqltDisconnect,
110 +  sqltDistinct,
111 +  sqltDouble,
112 +  sqltDrop,
113 +  sqltElse,
114 +  sqltEnd,
115 +  sqltEscape,
116 +  sqltExecute,
117 +  sqltExists,
118 +  sqltExternal,
119 +  sqltExtract,
120 +  sqltFalse,
121 +  sqltFetch,
122 +  sqltFilter,
123 +  sqltFloat,
124 +  sqltFor,
125 +  sqltForeign,
126 +  sqltFrom,
127 +  sqltFull,
128 +  sqltFunction,
129 +  sqltGdscode,
130 +  sqltGlobal,
131 +  sqltGrant,
132 +  sqltGroup,
133 +  sqltHaving,
134 +  sqltHour,
135 +  sqltIn,
136 +  sqltIndex,
137 +  sqltInner,
138 +  sqltInsensitive,
139 +  sqltInsert,
140 +  sqltInserting,
141 +  sqltInt,
142 +  sqltInteger,
143 +  sqltInto,
144 +  sqltIs,
145 +  sqltJoin,
146 +  sqltKey,
147 +  sqltLeading,
148 +  sqltLeft,
149 +  sqltLike,
150 +  sqltLong,
151 +  sqltLower,
152 +  sqltMax,
153 +  sqltMaximum_Segment,
154 +  sqltMerge,
155 +  sqltMin,
156 +  sqltMinute,
157 +  sqltMonth,
158 +  sqltNational,
159 +  sqltNatural,
160 +  sqltNchar,
161 +  sqltNo,
162 +  sqltNot,
163 +  sqltNull,
164 +  sqltNumeric,
165 +  sqltOctet_Length,
166 +  sqltOf,
167 +  sqltOffset,
168 +  sqltOn,
169 +  sqltOnly,
170 +  sqltOpen,
171 +  sqltOr,
172 +  sqltOrder,
173 +  sqltOuter,
174 +  sqltOver,
175 +  sqltParameter,
176 +  sqltPlan,
177 +  sqltPosition,
178 +  sqltPost_Event,
179 +  sqltPrecision,
180 +  sqltPrimary,
181 +  sqltProcedure,
182 +  sqltRdbDb_Key,
183 +  sqltRdbRecord_Version,
184 +  sqltReal,
185 +  sqltRecord_Version,
186 +  sqltRecreate,
187 +  sqltRecursive,
188 +  sqltReferences,
189 +  sqltRegr_Avgx,
190 +  sqltRegr_Avgy,
191 +  sqltRegr_Count,
192 +  sqltRegr_Intercept,
193 +  sqltRegr_R2,
194 +  sqltRegr_Slope,
195 +  sqltRegr_Sxx,
196 +  sqltRegr_Sxy,
197 +  sqltRegr_Syy,
198 +  sqltRelease,
199 +  sqltReturn,
200 +  sqltReturning_Values,
201 +  sqltReturns,
202 +  sqltRevoke,
203 +  sqltRight,
204 +  sqltRollback,
205 +  sqltRow,
206 +  sqltRows,
207 +  sqltRow_Count,
208 +  sqltSavepoint,
209 +  sqltScroll,
210 +  sqltSecond,
211 +  sqltSelect,
212 +  sqltSensitive,
213 +  sqltSet,
214 +  sqltSimilar,
215 +  sqltSmallint,
216 +  sqltSome,
217 +  sqltSqlcode,
218 +  sqltSqlstate,
219 +  sqltStart,
220 +  sqltStddev_Pop,
221 +  sqltStddev_Samp,
222 +  sqltSum,
223 +  sqltTable,
224 +  sqltThen,
225 +  sqltTime,
226 +  sqltTimestamp,
227 +  sqltTo,
228 +  sqltTrailing,
229 +  sqltTrigger,
230 +  sqltTrim,
231 +  sqltTrue,
232 +  sqltUnion,
233 +  sqltUnique,
234 +  sqltUnknown,
235 +  sqltUpdate,
236 +  sqltUpdating,
237 +  sqltUpper,
238 +  sqltUser,
239 +  sqltUsing,
240 +  sqltValue,
241 +  sqltValues,
242 +  sqltVar_Pop,
243 +  sqltVar_Samp,
244 +  sqltVarchar,
245 +  sqltVariable,
246 +  sqltVarying,
247 +  sqltView,
248 +  sqltWhen,
249 +  sqltWhere,
250 +  sqltWhile,
251 +  sqltWith,
252 +  sqltYear,
253 +
254 +  {symbols}
255 +
256 +  sqltSpace,
257 +  sqltSemiColon,
258 +  sqltPlaceholder,
259 +  sqltSingleQuotes,
260 +  sqltDoubleQuotes,
261 +  sqltBackslash,
262 +  sqltComma,
263 +  sqltPeriod,
264 +  sqltEquals,
265 +  sqltOtherCharacter,
266 +  sqltIdentifier,
267 +  sqltIdentifierInDoubleQuotes,
268 +  sqltNumberString,
269 +  sqltString,
270 +  sqltParam,
271 +  sqltQuotedParam,
272 +  sqltColon,
273 +  sqltComment,
274 +  sqltCommentLine,
275 +  sqltQuotedString,
276 +  sqltAsterisk,
277 +  sqltForwardSlash,
278 +  sqltOpenSquareBracket,
279 +  sqltCloseSquareBracket,
280 +  sqltOpenBracket,
281 +  sqltCloseBracket,
282 +  sqltPipe,
283 +  sqltMinus,
284 +  sqltConcatSymbol,
285 +  sqltLT,
286 +  sqltGT,
287 +  sqltCR,
288 +  sqltEOL,
289 +  sqltEOF,
290 +  sqltInit
291 +  );
292 +
293 +  TSQLReservedWords = sqltAdd..sqltYear;
294 +
295   const
296    CRLF = #13 + #10;
297    CR   = #13;
# Line 54 | Line 299 | const
299    TAB  = #9;
300    NULL_TERMINATOR = #0;
301  
302 <  sqlReservedWords: array [0..198] of string = (
302 >  {$IFNDEF FPC}
303 >  LineEnding = CRLF;
304 >  {$ENDIF}
305 >
306 >  {SQL Reserved words in alphabetical order}
307 >
308 >  sqlReservedWords: array [TSQLReservedWords] of string = (
309    'ADD',
310    'ADMIN',
311    'ALL',
# Line 206 | Line 457 | const
457    'RIGHT',
458    'ROLLBACK',
459    'ROW',
209  'ROW_COUNT',
460    'ROWS',
461 +  'ROW_COUNT',
462    'SAVEPOINT',
463    'SCROLL',
464    'SECOND',
# Line 219 | Line 470 | const
470    'SOME',
471    'SQLCODE',
472    'SQLSTATE',
222  'SQLSTATE',
473    'START',
474    'STDDEV_POP',
475    'STDDEV_SAMP',
# Line 256 | Line 506 | const
506    'YEAR'
507    );
508  
509 + type
510 +  {The TSQLTokeniser class provides a common means to parse an SQL statement, or
511 +   even a stream of SQL Statements. The TSQLStringTokeniser class is instantiated
512 +   with a single SQL statement or a set of concatenated statements. The TSQLStreamTokeniser
513 +   is instantiated with a stream from which the SQL statements are read.
514 +
515 +   Successive calls to GetNextToken then return each SQL token. The TokenText contains
516 +   either the single character, the identifier or reserved word, the string or comment.}
517 +
518 +  { TSQLTokeniser }
519 +
520 +  TSQLTokeniser = class
521 +  private
522 +    const
523 +      TokenQueueMaxSize = 64;
524 +    type
525 +      TLexState = (stDefault, stInCommentLine, stInComment, stSingleQuoted, stDoubleQuoted,
526 +                   stInIdentifier, stInNumeric);
527 +
528 +      TTokenQueueItem = record
529 +                          token: TSQLTokens;
530 +                          text: AnsiString;
531 +                        end;
532 +      TTokenQueueState = (tsHold, tsRelease);
533 +
534 +  private
535 +    FLastChar: AnsiChar;
536 +    FState: TLexState;
537 +    FSkipNext: boolean;
538 +    function GetNext: TSQLTokens;
539 +
540 +    {The token Queue is available for use by descendents so that they can
541 +     hold back tokens in order to lookahead by token rather than just a single
542 +     character}
543 +
544 +  private
545 +    FTokenQueue: array[0..TokenQueueMaxSize] of TTokenQueueItem;
546 +    FQueueState: TTokenQueueState;
547 +    FQFirst: integer;  {first and last pointers first=last => queue empty}
548 +    FQLast: integer;
549 +    FEOF: boolean;
550 +    procedure PopQueue(var token: TSQLTokens);
551 +  protected
552 +    FString: AnsiString;
553 +    FNextToken: TSQLTokens;
554 +    procedure Assign(source: TSQLTokeniser); virtual;
555 +    function GetChar: AnsiChar; virtual; abstract;
556 +    function TokenFound(var token: TSQLTokens): boolean; virtual;
557 +    function InternalGetNextToken: TSQLTokens; virtual;
558 +    procedure Reset; virtual;
559 +
560 +    {Token stack}
561 +    procedure QueueToken(token: TSQLTokens; text:AnsiString); overload;
562 +    procedure QueueToken(token: TSQLTokens); overload;
563 +    procedure ResetQueue; overload;
564 +    procedure ResetQueue(token: TSQLTokens; text:AnsiString); overload;
565 +    procedure ResetQueue(token: TSQLTokens); overload;
566 +    procedure ReleaseQueue(var token: TSQLTokens); overload;
567 +    procedure ReleaseQueue; overload;
568 +    function GetQueuedText: AnsiString;
569 +    procedure SetTokenText(text: AnsiString);
570 +
571 +  public
572 +    const
573 +        DefaultTerminator = ';';
574 +  public
575 +    constructor Create;
576 +    destructor Destroy; override;
577 +    function GetNextToken: TSQLTokens;
578 +    property EOF: boolean read FEOF;
579 +    property TokenText: AnsiString read FString;
580 +  end;
581 +
582 +  { TSQLwithNamedParamsTokeniser }
583 +
584 +  TSQLwithNamedParamsTokeniser = class(TSQLTokeniser)
585 +  private
586 +    type
587 +      TSQLState = (stInit,stInParam,stInBlock, stInArrayDim);
588 +  private
589 +    FState: TSQLState;
590 +    FNested: integer;
591 +  protected
592 +    procedure Assign(source: TSQLTokeniser); override;
593 +    procedure Reset; override;
594 +    function TokenFound(var token: TSQLTokens): boolean; override;
595 +  end;
596 +
597 +    { TSQLParamProcessor }
598 +
599 +  TSQLParamProcessor = class(TSQLwithNamedParamsTokeniser)
600 +  private
601 +  const
602 +    sIBXParam = 'IBXParam';  {do not localize}
603 +  private
604 +    FInString: AnsiString;
605 +    FIndex: integer;
606 +    function DoExecute(GenerateParamNames: boolean;
607 +        var slNames: TStrings): AnsiString;
608 +  protected
609 +    function GetChar: AnsiChar; override;
610 +  public
611 +    class function Execute(sSQL: AnsiString; GenerateParamNames: boolean;
612 +        var slNames: TStrings): AnsiString;
613 +  end;
614 +
615 +
616   function Max(n1, n2: Integer): Integer;
617   function Min(n1, n2: Integer): Integer;
618   function RandomString(iLength: Integer): AnsiString;
619   function RandomInteger(iLow, iHigh: Integer): Integer;
620   function StripString(st: AnsiString; CharsToStrip: AnsiString): AnsiString;
621   function ExtractIdentifier(Dialect: Integer; Value: AnsiString): AnsiString;
622 + function FindReservedWord(w: AnsiString; var token: TSQLTokens): boolean;
623 + function IsReservedWord(w: AnsiString): boolean;
624   function QuoteIdentifier(Dialect: Integer; Value: AnsiString): AnsiString;
625   function QuoteIdentifierIfNeeded(Dialect: Integer; Value: AnsiString): AnsiString;
626   function Space2Underscore(s: AnsiString): AnsiString;
# Line 277 | Line 636 | function GetProtocol(ConnectString: Ansi
636  
637   implementation
638  
639 + uses FBMessages
640 +
641   {$IFDEF HASREQEX}
642 < uses RegExpr;
643 < {$ENDIF}
642 > ,RegExpr
643 > {$ENDIF};
644  
645   function Max(n1, n2: Integer): Integer;
646   begin
# Line 343 | Line 704 | begin
704    Result := Value;
705   end;
706  
707 + {Returns true if "w" is a Firebird SQL reserved word, and the
708 + corresponding TSQLTokens value.}
709 +
710 + function FindReservedWord(w: AnsiString; var token: TSQLTokens): boolean;
711 + var i: TSQLTokens;
712 + begin
713 +   Result := true;
714 +   w := AnsiUpperCase(Trim(w));
715 +   for i := Low(TSQLReservedWords) to High(TSQLReservedWords) do
716 +   begin
717 +       if w = sqlReservedWords[i] then
718 +       begin
719 +         token := i;
720 +         Exit;
721 +       end;
722 +       if w <  sqlReservedWords[i] then
723 +         break;
724 +   end;
725 +   Result := false;
726 + end;
727 +
728   {Returns true if "w" is a Firebird SQL reserved word}
729  
730   function IsReservedWord(w: AnsiString): boolean;
731 < var i: integer;
731 > var token: TSQLTokens;
732   begin
733 <     Result := true;
352 <     for i := 0 to Length(sqlReservedWords) - 1 do
353 <         if w = sqlReservedWords[i] then
354 <            Exit;
355 <     Result := false;
733 >  Result := FindReservedWord(w,token);
734   end;
735  
736   {Format an SQL Identifier according to SQL Dialect}
737  
738   function QuoteIdentifier(Dialect: Integer; Value: AnsiString): AnsiString;
739   begin
740 +  Value := TrimRight(Value);
741    if Dialect = 1 then
742 <    Value := AnsiUpperCase(Trim(Value))
742 >    Value := AnsiUpperCase(Value)
743    else
744      Value := '"' + StringReplace (Value, '""', '"', [rfReplaceAll]) + '"';
745    Result := Value;
# Line 591 | Line 970 | end;
970  
971   function QuoteIdentifierIfNeeded(Dialect: Integer; Value: AnsiString): AnsiString;
972   begin
973 +  Value := TrimRight(Value);
974    if (Dialect = 3) and
975      (IsReservedWord(Value) or not IsSQLIdentifier(Value) or (AnsiUpperCase(Value) <> Value)) then
976       Result := '"' + StringReplace (TrimRight(Value), '"', '""', [rfReplaceAll]) + '"'
# Line 617 | Line 997 | begin
997    Result := StringReplace(s,'''','''''',[rfReplaceAll]);
998   end;
999  
1000 + { TSQLParamProcessor }
1001 +
1002 + function TSQLParamProcessor.DoExecute(GenerateParamNames: boolean;
1003 +  var slNames: TStrings): AnsiString;
1004 + var token: TSQLTokens;
1005 +    iParamSuffix: Integer;
1006 + begin
1007 +  Result := '';
1008 +  iParamSuffix := 0;
1009 +
1010 +  while not EOF do
1011 +  begin
1012 +    token := GetNextToken;
1013 +    case token of
1014 +    sqltParam,
1015 +    sqltQuotedParam:
1016 +      begin
1017 +        Result := Result + '?';
1018 +        slNames.Add(TokenText);
1019 +      end;
1020 +
1021 +    sqltPlaceHolder:
1022 +      if GenerateParamNames then
1023 +      begin
1024 +        Inc(iParamSuffix);
1025 +        slNames.AddObject(sIBXParam + IntToStr(iParamSuffix),self); //Note local convention
1026 +                                            //add pointer to self to mark entry
1027 +        Result := Result + '?';
1028 +      end
1029 +      else
1030 +        IBError(ibxeSQLParseError, [SParamNameExpected]);
1031 +
1032 +    sqltQuotedString:
1033 +      Result := Result + '''' + SQLSafeString(TokenText) + '''';
1034 +
1035 +    sqltIdentifierInDoubleQuotes:
1036 +      Result := Result + '"' + StringReplace(TokenText,'"','""',[rfReplaceAll]) + '"';
1037 +
1038 +    sqltComment:
1039 +      Result := Result + '/*' + TokenText + '*/';
1040 +
1041 +    sqltCommentLine:
1042 +      Result := Result + '--' + TokenText + LineEnding;
1043 +
1044 +    sqltEOL:
1045 +      Result := Result + LineEnding;
1046 +
1047 +    else
1048 +      Result := Result + TokenText;
1049 +    end;
1050 +  end;
1051 + end;
1052 +
1053 + function TSQLParamProcessor.GetChar: AnsiChar;
1054 + begin
1055 +  if FIndex <= Length(FInString) then
1056 +  begin
1057 +    Result := FInString[FIndex];
1058 +    Inc(FIndex);
1059 +  end
1060 +  else
1061 +    Result := #0;
1062 + end;
1063 +
1064 + class function TSQLParamProcessor.Execute(sSQL: AnsiString;
1065 +  GenerateParamNames: boolean; var slNames: TStrings): AnsiString;
1066 + begin
1067 +  with self.Create do
1068 +  try
1069 +    FInString := sSQL;
1070 +    FIndex := 1;
1071 +    Result := DoExecute(GenerateParamNames,slNames);
1072 +  finally
1073 +    Free;
1074 +  end;
1075 + end;
1076 +
1077 + { TSQLwithNamedParamsTokeniser }
1078 +
1079 + procedure TSQLwithNamedParamsTokeniser.Assign(source: TSQLTokeniser);
1080 + begin
1081 +  inherited Assign(source);
1082 +  if source is TSQLwithNamedParamsTokeniser then
1083 +  begin
1084 +    FState := TSQLwithNamedParamsTokeniser(source).FState;
1085 +    FNested := TSQLwithNamedParamsTokeniser(source).FNested;
1086 +  end;
1087 + end;
1088 +
1089 + procedure TSQLwithNamedParamsTokeniser.Reset;
1090 + begin
1091 +  inherited Reset;
1092 +  FState := stInit;
1093 +  FNested := 0;
1094 + end;
1095 +
1096 + function TSQLwithNamedParamsTokeniser.TokenFound(var token: TSQLTokens
1097 +  ): boolean;
1098 + begin
1099 +  Result := inherited TokenFound(token);
1100 +  if not Result then Exit;
1101 +
1102 +  case FState of
1103 +  stInit:
1104 +    begin
1105 +      case token of
1106 +      sqltColon:
1107 +        begin
1108 +          FState := stInParam;
1109 +          ResetQueue(token);
1110 +        end;
1111 +
1112 +      sqltBegin:
1113 +        begin
1114 +          FState := stInBlock;
1115 +          FNested := 1;
1116 +        end;
1117 +
1118 +      sqltOpenSquareBracket:
1119 +          FState := stInArrayDim;
1120 +
1121 +      end;
1122 +    end;
1123 +
1124 +  stInParam:
1125 +    begin
1126 +      case token of
1127 +      sqltIdentifier:
1128 +        token := sqltParam;
1129 +
1130 +      sqltIdentifierInDoubleQuotes:
1131 +        token := sqltQuotedParam;
1132 +
1133 +      else
1134 +        begin
1135 +          QueueToken(token);
1136 +          ReleaseQueue(token);
1137 +        end;
1138 +      end;
1139 +      FState := stInit;
1140 +    end;
1141 +
1142 +  stInBlock:
1143 +    begin
1144 +      case token of
1145 +      sqltBegin:
1146 +          Inc(FNested);
1147 +
1148 +      sqltEnd:
1149 +        begin
1150 +          Dec(FNested);
1151 +          if FNested = 0 then
1152 +            FState := stInit;
1153 +        end;
1154 +      end;
1155 +    end;
1156 +
1157 +    stInArrayDim:
1158 +      begin
1159 +        if token = sqltCloseSquareBracket then
1160 +            FState := stInit;
1161 +      end;
1162 +    end;
1163 +
1164 +  Result := (FState <> stInParam);
1165 + end;
1166 +
1167 + { TSQLTokeniser }
1168 +
1169 + function TSQLTokeniser.GetNext: TSQLTokens;
1170 + var C: AnsiChar;
1171 + begin
1172 +  if EOF then
1173 +    Result := sqltEOF
1174 +  else
1175 +  begin
1176 +    C := GetChar;
1177 +    case C of
1178 +    #0:
1179 +      Result := sqltEOF;
1180 +    ' ',TAB:
1181 +      Result := sqltSpace;
1182 +    '0'..'9':
1183 +      Result := sqltNumberString;
1184 +    ';':
1185 +      Result := sqltSemiColon;
1186 +    '?':
1187 +      Result := sqltPlaceholder;
1188 +    '|':
1189 +      Result := sqltPipe;
1190 +    '"':
1191 +      Result := sqltDoubleQuotes;
1192 +    '''':
1193 +      Result := sqltSingleQuotes;
1194 +    '/':
1195 +      Result := sqltForwardSlash;
1196 +    '\':
1197 +      Result := sqltBackslash;
1198 +    '*':
1199 +      Result := sqltAsterisk;
1200 +    '(':
1201 +      Result := sqltOpenBracket;
1202 +    ')':
1203 +      Result := sqltCloseBracket;
1204 +    ':':
1205 +      Result := sqltColon;
1206 +    ',':
1207 +      Result := sqltComma;
1208 +    '.':
1209 +      Result := sqltPeriod;
1210 +    '=':
1211 +      Result := sqltEquals;
1212 +    '[':
1213 +      Result := sqltOpenSquareBracket;
1214 +    ']':
1215 +      Result := sqltCloseSquareBracket;
1216 +    '-':
1217 +      Result := sqltMinus;
1218 +    '<':
1219 +      Result := sqltLT;
1220 +    '>':
1221 +      Result := sqltGT;
1222 +    CR:
1223 +      Result := sqltCR;
1224 +    LF:
1225 +      Result := sqltEOL;
1226 +    else
1227 +      if C in ValidSQLIdentifierChars then
1228 +        Result := sqltIdentifier
1229 +      else
1230 +        Result := sqltOtherCharacter;
1231 +    end;
1232 +    FLastChar := C
1233 +  end;
1234 +  FNextToken := Result;
1235 + end;
1236 +
1237 + procedure TSQLTokeniser.PopQueue(var token: TSQLTokens);
1238 + begin
1239 +  if FQFirst = FQLast then
1240 +    IBError(ibxeTokenQueueUnderflow,[]);
1241 +  token := FTokenQueue[FQFirst].token;
1242 +  FString := FTokenQueue[FQFirst].text;
1243 +  Inc(FQFirst);
1244 +  if FQFirst = FQLast then
1245 +    FQueueState := tsHold;
1246 + end;
1247 +
1248 + procedure TSQLTokeniser.Assign(source: TSQLTokeniser);
1249 + begin
1250 +  FString := source.FString;
1251 +  FNextToken := source.FNextToken;
1252 +  FTokenQueue := source.FTokenQueue;
1253 +  FQueueState := source.FQueueState;
1254 +  FQFirst := source.FQFirst;
1255 +  FQLast := source.FQLast;
1256 + end;
1257 +
1258 + function TSQLTokeniser.TokenFound(var token: TSQLTokens): boolean;
1259 + begin
1260 +  Result := (FState = stDefault);
1261 +  if Result and (token = sqltIdentifier)  then
1262 +    FindReservedWord(FString,token);
1263 + end;
1264 +
1265 + procedure TSQLTokeniser.QueueToken(token: TSQLTokens; text: AnsiString);
1266 + begin
1267 +  if FQLast > TokenQueueMaxSize then
1268 +    IBError(ibxeTokenQueueOverflow,[]);
1269 +  FTokenQueue[FQLast].token := token;
1270 +  FTokenQueue[FQLast].text := text;
1271 +  Inc(FQLast);
1272 + end;
1273 +
1274 + procedure TSQLTokeniser.QueueToken(token: TSQLTokens);
1275 + begin
1276 +  QueueToken(token,TokenText);
1277 + end;
1278 +
1279 + procedure TSQLTokeniser.ResetQueue;
1280 + begin
1281 +  FQFirst := 0;
1282 +  FQLast := 0;
1283 +  FQueueState := tsHold;
1284 + end;
1285 +
1286 + procedure TSQLTokeniser.ResetQueue(token: TSQLTokens; text: AnsiString);
1287 + begin
1288 +  ResetQueue;
1289 +  QueueToken(token,text);
1290 + end;
1291 +
1292 + procedure TSQLTokeniser.ResetQueue(token: TSQLTokens);
1293 + begin
1294 +  ResetQueue;
1295 +  QueueToken(token);
1296 + end;
1297 +
1298 + procedure TSQLTokeniser.ReleaseQueue(var token: TSQLTokens);
1299 + begin
1300 +  FQueueState := tsRelease;
1301 +  PopQueue(token);
1302 + end;
1303 +
1304 + procedure TSQLTokeniser.ReleaseQueue;
1305 + begin
1306 +  FQueueState := tsRelease;
1307 + end;
1308 +
1309 + function TSQLTokeniser.GetQueuedText: AnsiString;
1310 + var i: integer;
1311 + begin
1312 +  Result := '';
1313 +  for i := FQFirst to FQLast do
1314 +    Result := Result + FTokenQueue[i].text;
1315 + end;
1316 +
1317 + procedure TSQLTokeniser.SetTokenText(text: AnsiString);
1318 + begin
1319 +  FString := text;
1320 + end;
1321 +
1322 + constructor TSQLTokeniser.Create;
1323 + begin
1324 +  inherited Create;
1325 +  Reset;
1326 + end;
1327 +
1328 + destructor TSQLTokeniser.Destroy;
1329 + begin
1330 +  Reset;
1331 +  inherited Destroy;
1332 + end;
1333 +
1334 + procedure TSQLTokeniser.Reset;
1335 + begin
1336 +  FNextToken := sqltInit;
1337 +  FState := stDefault;
1338 +  FString := '';
1339 +  FEOF := false;
1340 +  ResetQueue;
1341 + end;
1342 +
1343 + function TSQLTokeniser.GetNextToken: TSQLTokens;
1344 + begin
1345 +  if FQueueState = tsRelease then
1346 +  repeat
1347 +    PopQueue(Result);
1348 +    FEOF := Result = sqltEOF;
1349 +    if TokenFound(Result) then
1350 +      Exit;
1351 +  until FQueueState <> tsRelease;
1352 +
1353 +  Result := InternalGetNextToken;
1354 + end;
1355 +
1356 + {a simple lookahead one algorithm to extra the next symbol}
1357 +
1358 + function TSQLTokeniser.InternalGetNextToken: TSQLTokens;
1359 + var C: AnsiChar;
1360 + begin
1361 +  Result := sqltEOF;
1362 +
1363 +  if FNextToken = sqltInit then
1364 +    GetNext;
1365 +
1366 +  repeat
1367 +    Result := FNextToken;
1368 +    C := FLastChar;
1369 +    GetNext;
1370 +
1371 +    if FSkipNext then
1372 +    begin
1373 +      FSkipNext := false;
1374 +      continue;
1375 +    end;
1376 +
1377 +    case FState of
1378 +    stInComment:
1379 +      begin
1380 +        if (Result = sqltAsterisk) and (FNextToken = sqltForwardSlash) then
1381 +        begin
1382 +          FState := stDefault;
1383 +          Result := sqltComment;
1384 +          GetNext;
1385 +        end
1386 +        else
1387 +          FString := FString + C;
1388 +      end;
1389 +
1390 +    stInCommentLine:
1391 +      begin
1392 +        case Result of
1393 +        sqltEOL:
1394 +          begin
1395 +            FState := stDefault;
1396 +            Result := sqltCommentLine;
1397 +          end;
1398 +
1399 +        sqltCR: {ignore};
1400 +
1401 +        else
1402 +          FString := FString + C;
1403 +        end;
1404 +      end;
1405 +
1406 +    stSingleQuoted:
1407 +      begin
1408 +        if (Result = sqltSingleQuotes) then
1409 +        begin
1410 +          if (FNextToken = sqltSingleQuotes) then
1411 +          begin
1412 +            FSkipNext := true;
1413 +            FString := FString + C;
1414 +          end
1415 +          else
1416 +          begin
1417 +            Result := sqltQuotedString;
1418 +            FState := stDefault;
1419 +          end;
1420 +        end
1421 +        else
1422 +          FString := FString + C;
1423 +      end;
1424 +
1425 +    stDoubleQuoted:
1426 +      begin
1427 +        if (Result = sqltDoubleQuotes) then
1428 +        begin
1429 +          if (FNextToken = sqltDoubleQuotes) then
1430 +          begin
1431 +            FSkipNext := true;
1432 +            FString := FString + C;
1433 +          end
1434 +          else
1435 +          begin
1436 +            Result := sqltIdentifierInDoubleQuotes;
1437 +            FState := stDefault;
1438 +          end;
1439 +        end
1440 +        else
1441 +          FString := FString + C;
1442 +      end;
1443 +
1444 +    stInIdentifier:
1445 +      begin
1446 +        FString := FString + C;
1447 +        Result := sqltIdentifier;
1448 +        if not (FNextToken in [sqltIdentifier,sqltNumberString]) then
1449 +          FState := stDefault
1450 +      end;
1451 +
1452 +    stInNumeric:
1453 +      begin
1454 +        FString := FString + C;
1455 +        if (Result = sqltPeriod) and (FNextToken = sqltPeriod) then
1456 +        begin
1457 +          {malformed decimal}
1458 +          FState := stInIdentifier;
1459 +          Result := sqltIdentifier
1460 +        end
1461 +        else
1462 +        begin
1463 +          if not (FNextToken in [sqltNumberString,sqltPeriod]) then
1464 +            FState := stDefault;
1465 +          Result := sqltNumberString;
1466 +        end;
1467 +      end;
1468 +
1469 +    else {stDefault}
1470 +      begin
1471 +        FString := C;
1472 +        case Result of
1473 +
1474 +        sqltPipe:
1475 +          if FNextToken = sqltPipe then
1476 +          begin
1477 +            Result := sqltConcatSymbol;
1478 +            FString := C + FLastChar;
1479 +            GetNext;
1480 +          end;
1481 +
1482 +        sqltForwardSlash:
1483 +          begin
1484 +            if FNextToken = sqltAsterisk then
1485 +            begin
1486 +              FString := '';
1487 +              GetNext;
1488 +              FState := stInComment;
1489 +            end
1490 +          end;
1491 +
1492 +        sqltMinus:
1493 +          begin
1494 +            if FNextToken = sqltMinus then
1495 +            begin
1496 +              FString := '';
1497 +              GetNext;
1498 +              FState := stInCommentLine;
1499 +            end;
1500 +          end;
1501 +
1502 +        sqltSingleQuotes:
1503 +          begin
1504 +            FString := '';
1505 +            FState := stSingleQuoted;
1506 +          end;
1507 +
1508 +        sqltDoubleQuotes:
1509 +          begin
1510 +            FString := '';
1511 +            FState := stDoubleQuoted;
1512 +          end;
1513 +
1514 +        sqltIdentifier:
1515 +          if FNextToken in [sqltIdentifier,sqltNumberString] then
1516 +            FState := stInIdentifier;
1517 +
1518 +        sqltNumberString:
1519 +          if FNextToken in [sqltNumberString,sqltPeriod] then
1520 +            FState := stInNumeric;
1521 +        end;
1522 +      end;
1523 +    end;
1524 +
1525 + //    writeln(FString);
1526 +    FEOF := Result = sqltEOF;
1527 +  until TokenFound(Result) or EOF;
1528 + end;
1529 +
1530   end.

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