1 /*
2 ** 2001 September 15
3 **
4 ** The author disclaims copyright to this source code. In place of
5 ** a legal notice, here is a blessing:
6 **
7 ** May you do good and not evil.
8 ** May you find forgiveness for yourself and forgive others.
9 ** May you share freely, never taking more than you give.
10 **
11 *************************************************************************
12 ** An tokenizer for SQL
13 **
14 ** This file contains C code that splits an SQL input string up into
15 ** individual tokens and sends those tokens one-by-one over to the
16 ** parser for analysis.
17 */
18 #include "sqliteInt.h"
19 #include <stdlib.h>
20
21 /*
22 ** The charMap() macro maps alphabetic characters into their
23 ** lower-case ASCII equivalent. On ASCII machines, this is just
24 ** an upper-to-lower case map. On EBCDIC machines we also need
25 ** to adjust the encoding. Only alphabetic characters and underscores
26 ** need to be translated.
27 */
28 #ifdef SQLITE_ASCII
29 # define charMap(X) sqlite3UpperToLower[(unsigned char)X]
30 #endif
31 #ifdef SQLITE_EBCDIC
32 # define charMap(X) ebcdicToAscii[(unsigned char)X]
33 const unsigned char ebcdicToAscii[] = {
34 /* 0 1 2 3 4 5 6 7 8 9 A B C D E F */
35 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x */
36 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 1x */
37 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 2x */
38 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 3x */
39 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 4x */
40 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 5x */
41 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 95, 0, 0, /* 6x */
42 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 7x */
43 0, 97, 98, 99,100,101,102,103,104,105, 0, 0, 0, 0, 0, 0, /* 8x */
44 0,106,107,108,109,110,111,112,113,114, 0, 0, 0, 0, 0, 0, /* 9x */
45 0, 0,115,116,117,118,119,120,121,122, 0, 0, 0, 0, 0, 0, /* Ax */
46 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* Bx */
47 0, 97, 98, 99,100,101,102,103,104,105, 0, 0, 0, 0, 0, 0, /* Cx */
48 0,106,107,108,109,110,111,112,113,114, 0, 0, 0, 0, 0, 0, /* Dx */
49 0, 0,115,116,117,118,119,120,121,122, 0, 0, 0, 0, 0, 0, /* Ex */
50 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* Fx */
51 };
52 #endif
53
54 /*
55 ** The sqlite3KeywordCode function looks up an identifier to determine if
56 ** it is a keyword. If it is a keyword, the token code of that keyword is
57 ** returned. If the input is not a keyword, TK_ID is returned.
58 **
59 ** The implementation of this routine was generated by a program,
60 ** mkkeywordhash.h, located in the tool subdirectory of the distribution.
61 ** The output of the mkkeywordhash.c program is written into a file
62 ** named keywordhash.h and then included into this source file by
63 ** the #include below.
64 */
65 #include "keywordhash.h"
66
67
68 /*
69 ** If X is a character that can be used in an identifier then
70 ** IdChar(X) will be true. Otherwise it is false.
71 **
72 ** For ASCII, any character with the high-order bit set is
73 ** allowed in an identifier. For 7-bit characters,
74 ** sqlite3IsIdChar[X] must be 1.
75 **
76 ** For EBCDIC, the rules are more complex but have the same
77 ** end result.
78 **
79 ** Ticket #1066. the SQL standard does not allow '$' in the
80 ** middle of identfiers. But many SQL implementations do.
81 ** SQLite will allow '$' in identifiers for compatibility.
82 ** But the feature is undocumented.
83 */
84 #ifdef SQLITE_ASCII
85 #define IdChar(C) ((sqlite3CtypeMap[(unsigned char)C]&0x46)!=0)
86 #endif
87 #ifdef SQLITE_EBCDIC
88 const char sqlite3IsEbcdicIdChar[] = {
89 /* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
90 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, /* 4x */
91 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, /* 5x */
92 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, /* 6x */
93 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, /* 7x */
94 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, /* 8x */
95 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, /* 9x */
96 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, /* Ax */
97 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* Bx */
98 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, /* Cx */
99 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, /* Dx */
100 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, /* Ex */
101 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, /* Fx */
102 };
103 #define IdChar(C) (((c=C)>=0x42 && sqlite3IsEbcdicIdChar[c-0x40]))
104 #endif
105
106
107 /*
108 ** Return the length of the token that begins at z[0].
109 ** Store the token type in *tokenType before returning.
110 */
sqlite3GetToken(const unsigned char * z,int * tokenType)111 int sqlite3GetToken(const unsigned char *z, int *tokenType){
112 int i, c;
113 switch( *z ){
114 case ' ': case '\t': case '\n': case '\f': case '\r': {
115 testcase( z[0]==' ' );
116 testcase( z[0]=='\t' );
117 testcase( z[0]=='\n' );
118 testcase( z[0]=='\f' );
119 testcase( z[0]=='\r' );
120 for(i=1; sqlite3Isspace(z[i]); i++){}
121 *tokenType = TK_SPACE;
122 return i;
123 }
124 case '-': {
125 if( z[1]=='-' ){
126 /* IMP: R-15891-05542 -- syntax diagram for comments */
127 for(i=2; (c=z[i])!=0 && c!='\n'; i++){}
128 *tokenType = TK_SPACE; /* IMP: R-22934-25134 */
129 return i;
130 }
131 *tokenType = TK_MINUS;
132 return 1;
133 }
134 case '(': {
135 *tokenType = TK_LP;
136 return 1;
137 }
138 case ')': {
139 *tokenType = TK_RP;
140 return 1;
141 }
142 case ';': {
143 *tokenType = TK_SEMI;
144 return 1;
145 }
146 case '+': {
147 *tokenType = TK_PLUS;
148 return 1;
149 }
150 case '*': {
151 *tokenType = TK_STAR;
152 return 1;
153 }
154 case '/': {
155 if( z[1]!='*' || z[2]==0 ){
156 *tokenType = TK_SLASH;
157 return 1;
158 }
159 /* IMP: R-15891-05542 -- syntax diagram for comments */
160 for(i=3, c=z[2]; (c!='*' || z[i]!='/') && (c=z[i])!=0; i++){}
161 if( c ) i++;
162 *tokenType = TK_SPACE; /* IMP: R-22934-25134 */
163 return i;
164 }
165 case '%': {
166 *tokenType = TK_REM;
167 return 1;
168 }
169 case '=': {
170 *tokenType = TK_EQ;
171 return 1 + (z[1]=='=');
172 }
173 case '<': {
174 if( (c=z[1])=='=' ){
175 *tokenType = TK_LE;
176 return 2;
177 }else if( c=='>' ){
178 *tokenType = TK_NE;
179 return 2;
180 }else if( c=='<' ){
181 *tokenType = TK_LSHIFT;
182 return 2;
183 }else{
184 *tokenType = TK_LT;
185 return 1;
186 }
187 }
188 case '>': {
189 if( (c=z[1])=='=' ){
190 *tokenType = TK_GE;
191 return 2;
192 }else if( c=='>' ){
193 *tokenType = TK_RSHIFT;
194 return 2;
195 }else{
196 *tokenType = TK_GT;
197 return 1;
198 }
199 }
200 case '!': {
201 if( z[1]!='=' ){
202 *tokenType = TK_ILLEGAL;
203 return 2;
204 }else{
205 *tokenType = TK_NE;
206 return 2;
207 }
208 }
209 case '|': {
210 if( z[1]!='|' ){
211 *tokenType = TK_BITOR;
212 return 1;
213 }else{
214 *tokenType = TK_CONCAT;
215 return 2;
216 }
217 }
218 case ',': {
219 *tokenType = TK_COMMA;
220 return 1;
221 }
222 case '&': {
223 *tokenType = TK_BITAND;
224 return 1;
225 }
226 case '~': {
227 *tokenType = TK_BITNOT;
228 return 1;
229 }
230 case '`':
231 case '\'':
232 case '"': {
233 int delim = z[0];
234 testcase( delim=='`' );
235 testcase( delim=='\'' );
236 testcase( delim=='"' );
237 for(i=1; (c=z[i])!=0; i++){
238 if( c==delim ){
239 if( z[i+1]==delim ){
240 i++;
241 }else{
242 break;
243 }
244 }
245 }
246 if( c=='\'' ){
247 *tokenType = TK_STRING;
248 return i+1;
249 }else if( c!=0 ){
250 *tokenType = TK_ID;
251 return i+1;
252 }else{
253 *tokenType = TK_ILLEGAL;
254 return i;
255 }
256 }
257 case '.': {
258 #ifndef SQLITE_OMIT_FLOATING_POINT
259 if( !sqlite3Isdigit(z[1]) )
260 #endif
261 {
262 *tokenType = TK_DOT;
263 return 1;
264 }
265 /* If the next character is a digit, this is a floating point
266 ** number that begins with ".". Fall thru into the next case */
267 }
268 case '0': case '1': case '2': case '3': case '4':
269 case '5': case '6': case '7': case '8': case '9': {
270 testcase( z[0]=='0' ); testcase( z[0]=='1' ); testcase( z[0]=='2' );
271 testcase( z[0]=='3' ); testcase( z[0]=='4' ); testcase( z[0]=='5' );
272 testcase( z[0]=='6' ); testcase( z[0]=='7' ); testcase( z[0]=='8' );
273 testcase( z[0]=='9' );
274 *tokenType = TK_INTEGER;
275 for(i=0; sqlite3Isdigit(z[i]); i++){}
276 #ifndef SQLITE_OMIT_FLOATING_POINT
277 if( z[i]=='.' ){
278 i++;
279 while( sqlite3Isdigit(z[i]) ){ i++; }
280 *tokenType = TK_FLOAT;
281 }
282 if( (z[i]=='e' || z[i]=='E') &&
283 ( sqlite3Isdigit(z[i+1])
284 || ((z[i+1]=='+' || z[i+1]=='-') && sqlite3Isdigit(z[i+2]))
285 )
286 ){
287 i += 2;
288 while( sqlite3Isdigit(z[i]) ){ i++; }
289 *tokenType = TK_FLOAT;
290 }
291 #endif
292 while( IdChar(z[i]) ){
293 *tokenType = TK_ILLEGAL;
294 i++;
295 }
296 return i;
297 }
298 case '[': {
299 for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){}
300 *tokenType = c==']' ? TK_ID : TK_ILLEGAL;
301 return i;
302 }
303 case '?': {
304 *tokenType = TK_VARIABLE;
305 for(i=1; sqlite3Isdigit(z[i]); i++){}
306 return i;
307 }
308 case '#': {
309 for(i=1; sqlite3Isdigit(z[i]); i++){}
310 if( i>1 ){
311 /* Parameters of the form #NNN (where NNN is a number) are used
312 ** internally by sqlite3NestedParse. */
313 *tokenType = TK_REGISTER;
314 return i;
315 }
316 /* Fall through into the next case if the '#' is not followed by
317 ** a digit. Try to match #AAAA where AAAA is a parameter name. */
318 }
319 #ifndef SQLITE_OMIT_TCL_VARIABLE
320 case '$':
321 #endif
322 case '@': /* For compatibility with MS SQL Server */
323 case ':': {
324 int n = 0;
325 testcase( z[0]=='$' ); testcase( z[0]=='@' ); testcase( z[0]==':' );
326 *tokenType = TK_VARIABLE;
327 for(i=1; (c=z[i])!=0; i++){
328 if( IdChar(c) ){
329 n++;
330 #ifndef SQLITE_OMIT_TCL_VARIABLE
331 }else if( c=='(' && n>0 ){
332 do{
333 i++;
334 }while( (c=z[i])!=0 && !sqlite3Isspace(c) && c!=')' );
335 if( c==')' ){
336 i++;
337 }else{
338 *tokenType = TK_ILLEGAL;
339 }
340 break;
341 }else if( c==':' && z[i+1]==':' ){
342 i++;
343 #endif
344 }else{
345 break;
346 }
347 }
348 if( n==0 ) *tokenType = TK_ILLEGAL;
349 return i;
350 }
351 #ifndef SQLITE_OMIT_BLOB_LITERAL
352 case 'x': case 'X': {
353 testcase( z[0]=='x' ); testcase( z[0]=='X' );
354 if( z[1]=='\'' ){
355 *tokenType = TK_BLOB;
356 for(i=2; (c=z[i])!=0 && c!='\''; i++){
357 if( !sqlite3Isxdigit(c) ){
358 *tokenType = TK_ILLEGAL;
359 }
360 }
361 if( i%2 || !c ) *tokenType = TK_ILLEGAL;
362 if( c ) i++;
363 return i;
364 }
365 /* Otherwise fall through to the next case */
366 }
367 #endif
368 default: {
369 if( !IdChar(*z) ){
370 break;
371 }
372 for(i=1; IdChar(z[i]); i++){}
373 *tokenType = keywordCode((char*)z, i);
374 return i;
375 }
376 }
377 *tokenType = TK_ILLEGAL;
378 return 1;
379 }
380
381 /*
382 ** Run the parser on the given SQL string. The parser structure is
383 ** passed in. An SQLITE_ status code is returned. If an error occurs
384 ** then an and attempt is made to write an error message into
385 ** memory obtained from sqlite3_malloc() and to make *pzErrMsg point to that
386 ** error message.
387 */
sqlite3RunParser(Parse * pParse,const char * zSql,char ** pzErrMsg)388 int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){
389 int nErr = 0; /* Number of errors encountered */
390 int i; /* Loop counter */
391 void *pEngine; /* The LEMON-generated LALR(1) parser */
392 int tokenType; /* type of the next token */
393 int lastTokenParsed = -1; /* type of the previous token */
394 u8 enableLookaside; /* Saved value of db->lookaside.bEnabled */
395 sqlite3 *db = pParse->db; /* The database connection */
396 int mxSqlLen; /* Max length of an SQL string */
397
398
399 mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
400 if( db->activeVdbeCnt==0 ){
401 db->u1.isInterrupted = 0;
402 }
403 pParse->rc = SQLITE_OK;
404 pParse->zTail = zSql;
405 i = 0;
406 assert( pzErrMsg!=0 );
407 pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3Malloc);
408 if( pEngine==0 ){
409 db->mallocFailed = 1;
410 return SQLITE_NOMEM;
411 }
412 assert( pParse->pNewTable==0 );
413 assert( pParse->pNewTrigger==0 );
414 assert( pParse->nVar==0 );
415 assert( pParse->nVarExpr==0 );
416 assert( pParse->nVarExprAlloc==0 );
417 assert( pParse->apVarExpr==0 );
418 enableLookaside = db->lookaside.bEnabled;
419 if( db->lookaside.pStart ) db->lookaside.bEnabled = 1;
420 while( !db->mallocFailed && zSql[i]!=0 ){
421 assert( i>=0 );
422 pParse->sLastToken.z = &zSql[i];
423 pParse->sLastToken.n = sqlite3GetToken((unsigned char*)&zSql[i],&tokenType);
424 i += pParse->sLastToken.n;
425 if( i>mxSqlLen ){
426 pParse->rc = SQLITE_TOOBIG;
427 break;
428 }
429 switch( tokenType ){
430 case TK_SPACE: {
431 if( db->u1.isInterrupted ){
432 sqlite3ErrorMsg(pParse, "interrupt");
433 pParse->rc = SQLITE_INTERRUPT;
434 goto abort_parse;
435 }
436 break;
437 }
438 case TK_ILLEGAL: {
439 sqlite3DbFree(db, *pzErrMsg);
440 *pzErrMsg = sqlite3MPrintf(db, "unrecognized token: \"%T\"",
441 &pParse->sLastToken);
442 nErr++;
443 goto abort_parse;
444 }
445 case TK_SEMI: {
446 pParse->zTail = &zSql[i];
447 /* Fall thru into the default case */
448 }
449 default: {
450 sqlite3Parser(pEngine, tokenType, pParse->sLastToken, pParse);
451 lastTokenParsed = tokenType;
452 if( pParse->rc!=SQLITE_OK ){
453 goto abort_parse;
454 }
455 break;
456 }
457 }
458 }
459 abort_parse:
460 if( zSql[i]==0 && nErr==0 && pParse->rc==SQLITE_OK ){
461 if( lastTokenParsed!=TK_SEMI ){
462 sqlite3Parser(pEngine, TK_SEMI, pParse->sLastToken, pParse);
463 pParse->zTail = &zSql[i];
464 }
465 sqlite3Parser(pEngine, 0, pParse->sLastToken, pParse);
466 }
467 #ifdef YYTRACKMAXSTACKDEPTH
468 sqlite3StatusSet(SQLITE_STATUS_PARSER_STACK,
469 sqlite3ParserStackPeak(pEngine)
470 );
471 #endif /* YYDEBUG */
472 sqlite3ParserFree(pEngine, sqlite3_free);
473 db->lookaside.bEnabled = enableLookaside;
474 if( db->mallocFailed ){
475 pParse->rc = SQLITE_NOMEM;
476 }
477 if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){
478 sqlite3SetString(&pParse->zErrMsg, db, "%s", sqlite3ErrStr(pParse->rc));
479 }
480 assert( pzErrMsg!=0 );
481 if( pParse->zErrMsg ){
482 *pzErrMsg = pParse->zErrMsg;
483 sqlite3_log(pParse->rc, "%s", *pzErrMsg);
484 pParse->zErrMsg = 0;
485 nErr++;
486 }
487 if( pParse->pVdbe && pParse->nErr>0 && pParse->nested==0 ){
488 sqlite3VdbeDelete(pParse->pVdbe);
489 pParse->pVdbe = 0;
490 }
491 #ifndef SQLITE_OMIT_SHARED_CACHE
492 if( pParse->nested==0 ){
493 sqlite3DbFree(db, pParse->aTableLock);
494 pParse->aTableLock = 0;
495 pParse->nTableLock = 0;
496 }
497 #endif
498 #ifndef SQLITE_OMIT_VIRTUALTABLE
499 sqlite3_free(pParse->apVtabLock);
500 #endif
501
502 if( !IN_DECLARE_VTAB ){
503 /* If the pParse->declareVtab flag is set, do not delete any table
504 ** structure built up in pParse->pNewTable. The calling code (see vtab.c)
505 ** will take responsibility for freeing the Table structure.
506 */
507 sqlite3DeleteTable(db, pParse->pNewTable);
508 }
509
510 sqlite3DeleteTrigger(db, pParse->pNewTrigger);
511 sqlite3DbFree(db, pParse->apVarExpr);
512 sqlite3DbFree(db, pParse->aAlias);
513 while( pParse->pAinc ){
514 AutoincInfo *p = pParse->pAinc;
515 pParse->pAinc = p->pNext;
516 sqlite3DbFree(db, p);
517 }
518 while( pParse->pZombieTab ){
519 Table *p = pParse->pZombieTab;
520 pParse->pZombieTab = p->pNextZombie;
521 sqlite3DeleteTable(db, p);
522 }
523 if( nErr>0 && pParse->rc==SQLITE_OK ){
524 pParse->rc = SQLITE_ERROR;
525 }
526 return nErr;
527 }
528