/*
** 2001 September 15
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** An tokenizer for SQL
**
** This file contains C code that splits an SQL input string up into
** individual tokens and sends those tokens one-by-one over to the
** parser for analysis.
**
** $Id: tokenize.c,v 1.104 2005/06/22 08:48:06 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include <stdlib.h>
/*
** The sqlite3KeywordCode function looks up an identifier to determine if
** it is a keyword. If it is a keyword, the token code of that keyword is
** returned. If the input is not a keyword, TK_ID is returned.
**
** The implementation of this routine was generated by a program,
** mkkeywordhash.h, located in the tool subdirectory of the distribution.
** The output of the mkkeywordhash.c program is written into a file
** named keywordhash.h and then included into this source file by
** the #include below.
*/
#include "keywordhash.h"
/*
** If X is a character that can be used in an identifier and
** X&0x80==0 then isIdChar[X] will be 1. If X&0x80==0x80 then
** X is always an identifier character. (Hence all UTF-8
** characters can be part of an identifier). isIdChar[X] will
** be 0 for every character in the lower 128 ASCII characters
** that cannot be used as part of an identifier.
**
** In this implementation, an identifier can be a string of
** alphabetic characters, digits, and "_" plus any character
** with the high-order bit set. The latter rule means that
** any sequence of UTF-8 characters or characters taken from
** an extended ISO8859 character set can form an identifier.
**
** Ticket #1066. the SQL standard does not allow '$' in the
** middle of identfiers. But many SQL implementations do.
** SQLite will allow '$' in identifiers for compatibility.
** But the feature is undocumented.
*/
static const char isIdChar[] = {
/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 2x */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, /* 3x */
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 4x */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, /* 5x */
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 6x */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, /* 7x */
};
#define IdChar(C) (((c=C)&0x80)!=0 || (c>0x1f && isIdChar[c-0x20]))
/*
** Return the length of the token that begins at z[0].
** Store the token type in *tokenType before returning.
*/
static int getToken(const unsigned char *z, int *tokenType){
int i, c;
switch( *z ){
case ' ': case '\t': case '\n': case '\f': case '\r': {
for(i=1; isspace(z[i]); i++){}
*tokenType = TK_SPACE;
return i;
}
case '-': {
if( z[1]=='-' ){
for(i=2; (c=z[i])!=0 && c!='\n'; i++){}
*tokenType = TK_COMMENT;
return i;
}
*tokenType = TK_MINUS;
return 1;
}
case '(': {
*tokenType = TK_LP;
return 1;
}
case ')': {
*tokenType = TK_RP;
return 1;
}
case ';': {
*tokenType = TK_SEMI;
return 1;
}
case '+': {
*tokenType = TK_PLUS;
return 1;
}
case '*': {
*tokenType = TK_STAR;
return 1;
}
case '/': {
if( z[1]!='*' || z[2]==0 ){
*tokenType = TK_SLASH;
return 1;
}
for(i=3, c=z[2]; (c!='*' || z[i]!='/') && (c=z[i])!=0; i++){}
if( c ) i++;
*tokenType = TK_COMMENT;
return i;
}
case '%': {
*tokenType = TK_REM;
return 1;
}
case '=': {
*tokenType = TK_EQ;
return 1 + (z[1]=='=');
}
case '<': {
if( (c=z[1])=='=' ){
*tokenType = TK_LE;
return 2;
}else if( c=='>' ){
*tokenType = TK_NE;
return 2;
}else if( c=='<' ){
*tokenType = TK_LSHIFT;
return 2;
}else{
*tokenType = TK_LT;
return 1;
}
}
case '>': {
if( (c=z[1])=='=' ){
*tokenType = TK_GE;
return 2;
}else if( c=='>' ){
*tokenType = TK_RSHIFT;
return 2;
}else{
*tokenType = TK_GT;
return 1;
}
}
case '!': {
if( z[1]!='=' ){
*tokenType = TK_ILLEGAL;
return 2;
}else{
*tokenType = TK_NE;
return 2;
}
}
case '|': {
if( z[1]!='|' ){
*tokenType = TK_BITOR;
return 1;
}else{
*tokenType = TK_CONCAT;
return 2;
}
}
case ',': {
*tokenType = TK_COMMA;
return 1;
}
case '&': {
*tokenType = TK_BITAND;
return 1;
}
case '~': {
*tokenType = TK_BITNOT;
return 1;
}
case '\'': case '"': {
int delim = z[0];
for(i=1; (c=z[i])!=0; i++){
if( c==delim ){
if( z[i+1]==delim ){
i++;
}else{
break;
}
}
}
if( c ) i++;
*tokenType = TK_STRING;
return i;
}
case '.': {
*tokenType = TK_DOT;
return 1;
}
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9': {
*tokenType = TK_INTEGER;
for(i=1; isdigit(z[i]); i++){}
#ifndef SQLITE_OMIT_FLOATING_POINT
if( z[i]=='.' && isdigit(z[i+1]) ){
i += 2;
while( isdigit(z[i]) ){ i++; }
*tokenType = TK_FLOAT;
}
if( (z[i]=='e' || z[i]=='E') &&
( isdigit(z[i+1])
|| ((z[i+1]=='+' || z[i+1]=='-') && isdigit(z[i+2]))
)
){
i += 2;
while( isdigit(z[i]) ){ i++; }
*tokenType = TK_FLOAT;
}
#endif
return i;
}
case '[': {
for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){}
*tokenType = TK_ID;
return i;
}
case '?': {
*tokenType = TK_VARIABLE;
for(i=1; isdigit(z[i]); i++){}
return i;
}
case '#': {
for(i=1; isdigit(z[i]); i++){}
if( i>1 ){
/* Parameters of the form #NNN (where NNN is a number) are used
** internally by sqlite3NestedParse. */
*tokenType = TK_REGISTER;
return i;
}
/* Fall through into the next case if the '#' is not followed by
** a digit. Try to match #AAAA where AAAA is a parameter name. */
}
#ifndef SQLITE_OMIT_TCL_VARIABLE
case '$':
#endif
case ':': {
int n = 0;
*tokenType = TK_VARIABLE;
for(i=1; (c=z[i])!=0; i++){
if( IdChar(c) ){
n++;
#ifndef SQLITE_OMIT_TCL_VARIABLE
}else if( c=='(' && n>0 ){
do{
i++;
}while( (c=z[i])!=0 && !isspace(c) && c!=')' );
if( c==')' ){
i++;
}else{
*tokenType = TK_ILLEGAL;
}
break;
}else if( c==':' && z[i+1]==':' ){
i++;
#endif
}else{
break;
}
}
if( n==0 ) *tokenType = TK_ILLEGAL;
return i;
}
#ifndef SQLITE_OMIT_BLOB_LITERAL
case 'x': case 'X': {
if( (c=z[1])=='\'' || c=='"' ){
int delim = c;
*tokenType = TK_BLOB;
for(i=2; (c=z[i])!=0; i++){
if( c==delim ){
if( i%2 ) *tokenType = TK_ILLEGAL;
break;
}
if( !isxdigit(c) ){
*tokenType = TK_ILLEGAL;
return i;
}
}
if( c ) i++;
return i;
}
/* Otherwise fall through to the next case */
}
#endif
default: {
if( !IdChar(*z) ){
break;
}
for(i=1; IdChar(z[i]); i++){}
*tokenType = keywordCode((char*)z, i);
return i;
}
}
*tokenType = TK_ILLEGAL;
return 1;
}
int sqlite3GetToken(const unsigned char *z, int *tokenType){
return getToken(z, tokenType);
}
/*
** Run the parser on the given SQL string. The parser structure is
** passed in. An SQLITE_ status code is returned. If an error occurs
** and pzErrMsg!=NULL then an error message might be written into
** memory obtained from malloc() and *pzErrMsg made to point to that
** error message. Or maybe not.
*/
int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){
int nErr = 0;
int i;
void *pEngine;
int tokenType;
int lastTokenParsed = -1;
sqlite3 *db = pParse->db;
extern void *sqlite3ParserAlloc(void*(*)(int));
extern void sqlite3ParserFree(void*, void(*)(void*));
extern int sqlite3Parser(void*, int, Token, Parse*);
db->flags &= ~SQLITE_Interrupt;
pParse->rc = SQLITE_OK;
i = 0;
pEngine = sqlite3ParserAlloc((void*(*)(int))sqlite3MallocX);
if( pEngine==0 ){
sqlite3SetString(pzErrMsg, "out of memory", (char*)0);
return SQLITE_NOMEM;
}
assert( pParse->sLastToken.dyn==0 );
assert( pParse->pNewTable==0 );
assert( pParse->pNewTrigger==0 );
assert( pParse->nVar==0 );
assert( pParse->nVarExpr==0 );
assert( pParse->nVarExprAlloc==0 );
assert( pParse->apVarExpr==0 );
pParse->zTail = pParse->zSql = zSql;
while( sqlite3_malloc_failed==0 && zSql[i]!=0 ){
assert( i>=0 );
pParse->sLastToken.z = &zSql[i];
assert( pParse->sLastToken.dyn==0 );
pParse->sLastToken.n = getToken((unsigned char*)&zSql[i],&tokenType);
i += pParse->sLastToken.n;
switch( tokenType ){
case TK_SPACE:
case TK_COMMENT: {
if( (db->flags & SQLITE_Interrupt)!=0 ){
pParse->rc = SQLITE_INTERRUPT;
sqlite3SetString(pzErrMsg, "interrupt", (char*)0);
goto abort_parse;
}
break;
}
case TK_ILLEGAL: {
if( pzErrMsg ){
sqliteFree(*pzErrMsg);
*pzErrMsg = sqlite3MPrintf("unrecognized token: \"%T\"",
&pParse->sLastToken);
}
nErr++;
goto abort_parse;
}
case TK_SEMI: {
pParse->zTail = &zSql[i];
/* Fall thru into the default case */
}
default: {
sqlite3Parser(pEngine, tokenType, pParse->sLastToken, pParse);
lastTokenParsed = tokenType;
if( pParse->rc!=SQLITE_OK ){
goto abort_parse;
}
break;
}
}
}
abort_parse:
if( zSql[i]==0 && nErr==0 && pParse->rc==SQLITE_OK ){
if( lastTokenParsed!=TK_SEMI ){
sqlite3Parser(pEngine, TK_SEMI, pParse->sLastToken, pParse);
pParse->zTail = &zSql[i];
}
sqlite3Parser(pEngine, 0, pParse->sLastToken, pParse);
}
sqlite3ParserFree(pEngine, sqlite3FreeX);
if( sqlite3_malloc_failed ){
pParse->rc = SQLITE_NOMEM;
}
if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){
sqlite3SetString(&pParse->zErrMsg, sqlite3ErrStr(pParse->rc),
(char*)0);
}
if( pParse->zErrMsg ){
if( pzErrMsg && *pzErrMsg==0 ){
*pzErrMsg = pParse->zErrMsg;
}else{
sqliteFree(pParse->zErrMsg);
}
pParse->zErrMsg = 0;
if( !nErr ) nErr++;
}
if( pParse->pVdbe && pParse->nErr>0 && pParse->nested==0 ){
sqlite3VdbeDelete(pParse->pVdbe);
pParse->pVdbe = 0;
}
sqlite3DeleteTable(pParse->db, pParse->pNewTable);
sqlite3DeleteTrigger(pParse->pNewTrigger);
sqliteFree(pParse->apVarExpr);
if( nErr>0 && (pParse->rc==SQLITE_OK || pParse->rc==SQLITE_DONE) ){
pParse->rc = SQLITE_ERROR;
}
return nErr;
}
/* The sqlite3_complete() API may be omitted (to save code space) by
** defining the following symbol.
*/
#ifndef SQLITE_OMIT_COMPLETE
/*
** Token types used by the sqlite3_complete() routine. See the header
** comments on that procedure for additional information.
*/
#define tkSEMI 0
#define tkWS 1
#define tkOTHER 2
#define tkEXPLAIN 3
#define tkCREATE 4
#define tkTEMP 5
#define tkTRIGGER 6
#define tkEND 7
/*
** Return TRUE if the given SQL string ends in a semicolon.
**
** Special handling is require for CREATE TRIGGER statements.
** Whenever the CREATE TRIGGER keywords are seen, the statement
** must end with ";END;".
**
** This implementation uses a state machine with 7 states:
**
** (0) START At the beginning or end of an SQL statement. This routine
** returns 1 if it ends in the START state and 0 if it ends
** in any other state.
**
** (1) NORMAL We are in the middle of statement which ends with a single
** semicolon.
**
** (2) EXPLAIN The keyword EXPLAIN has been seen at the beginning of
** a statement.
**
** (3) CREATE The keyword CREATE has been seen at the beginning of a
** statement, possibly preceeded by EXPLAIN and/or followed by
** TEMP or TEMPORARY
**
** (4) TRIGGER We are in the middle of a trigger definition that must be
** ended by a semicolon, the keyword END, and another semicolon.
**
** (5) SEMI We've seen the first semicolon in the ";END;" that occurs at
** the end of a trigger definition.
**
** (6) END We've seen the ";END" of the ";END;" that occurs at the end
** of a trigger difinition.
**
** Transitions between states above are determined by tokens extracted
** from the input. The following tokens are significant:
**
** (0) tkSEMI A semicolon.
** (1) tkWS Whitespace
** (2) tkOTHER Any other SQL token.
** (3) tkEXPLAIN The "explain" keyword.
** (4) tkCREATE The "create" keyword.
** (5) tkTEMP The "temp" or "temporary" keyword.
** (6) tkTRIGGER The "trigger" keyword.
** (7) tkEND The "end" keyword.
**
** Whitespace never causes a state transition and is always ignored.
**
** If we compile with SQLITE_OMIT_TRIGGER, all of the computation needed
** to recognize the end of a trigger can be omitted. All we have to do
** is look for a semicolon that is not part of an string or comment.
*/
int sqlite3_complete(const char *zSql){
u8 state = 0; /* Current state, using numbers defined in header comment */
u8 token; /* Value of the next token */
#ifndef SQLITE_OMIT_TRIGGER
/* A complex statement machine used to detect the end of a CREATE TRIGGER
** statement. This is the normal case.
*/
static const u8 trans[7][8] = {
/* Token: */
/* State: ** SEMI WS OTHER EXPLAIN CREATE TEMP TRIGGER END */
/* 0 START: */ { 0, 0, 1, 2, 3, 1, 1, 1, },
/* 1 NORMAL: */ { 0, 1, 1, 1, 1, 1, 1, 1, },
/* 2 EXPLAIN: */ { 0, 2, 1, 1, 3, 1, 1, 1, },
/* 3 CREATE: */ { 0, 3, 1, 1, 1, 3, 4, 1, },
/* 4 TRIGGER: */ { 5, 4, 4, 4, 4, 4, 4, 4, },
/* 5 SEMI: */ { 5, 5, 4, 4, 4, 4, 4, 6, },
/* 6 END: */ { 0, 6, 4, 4, 4, 4, 4, 4, },
};
#else
/* If triggers are not suppored by this compile then the statement machine
** used to detect the end of a statement is much simplier
*/
static const u8 trans[2][3] = {
/* Token: */
/* State: ** SEMI WS OTHER */
/* 0 START: */ { 0, 0, 1, },
/* 1 NORMAL: */ { 0, 1, 1, },
};
#endif /* SQLITE_OMIT_TRIGGER */
while( *zSql ){
switch( *zSql ){
case ';': { /* A semicolon */
token = tkSEMI;
break;
}
case ' ':
case '\r':
case '\t':
case '\n':
case '\f': { /* White space is ignored */
token = tkWS;
break;
}
case '/': { /* C-style comments */
if( zSql[1]!='*' ){
token = tkOTHER;
break;
}
zSql += 2;
while( zSql[0] && (zSql[0]!='*' || zSql[1]!='/') ){ zSql++; }
if( zSql[0]==0 ) return 0;
zSql++;
token = tkWS;
break;
}
case '-': { /* SQL-style comments from "--" to end of line */
if( zSql[1]!='-' ){
token = tkOTHER;
break;
}
while( *zSql && *zSql!='\n' ){ zSql++; }
if( *zSql==0 ) return state==0;
token = tkWS;
break;
}
case '[': { /* Microsoft-style identifiers in [...] */
zSql++;
while( *zSql && *zSql!=']' ){ zSql++; }
if( *zSql==0 ) return 0;
token = tkOTHER;
break;
}
case '"': /* single- and double-quoted strings */
case '\'': {
int c = *zSql;
zSql++;
while( *zSql && *zSql!=c ){ zSql++; }
if( *zSql==0 ) return 0;
token = tkOTHER;
break;
}
default: {
int c;
if( IdChar((u8)*zSql) ){
/* Keywords and unquoted identifiers */
int nId;
for(nId=1; IdChar(zSql[nId]); nId++){}
#ifdef SQLITE_OMIT_TRIGGER
token = tkOTHER;
#else
switch( *zSql ){
case 'c': case 'C': {
if( nId==6 && sqlite3StrNICmp(zSql, "create", 6)==0 ){
token = tkCREATE;
}else{
token = tkOTHER;
}
break;
}
case 't': case 'T': {
if( nId==7 && sqlite3StrNICmp(zSql, "trigger", 7)==0 ){
token = tkTRIGGER;
}else if( nId==4 && sqlite3StrNICmp(zSql, "temp", 4)==0 ){
token = tkTEMP;
}else if( nId==9 && sqlite3StrNICmp(zSql, "temporary", 9)==0 ){
token = tkTEMP;
}else{
token = tkOTHER;
}
break;
}
case 'e': case 'E': {
if( nId==3 && sqlite3StrNICmp(zSql, "end", 3)==0 ){
token = tkEND;
}else
#ifndef SQLITE_OMIT_EXPLAIN
if( nId==7 && sqlite3StrNICmp(zSql, "explain", 7)==0 ){
token = tkEXPLAIN;
}else
#endif
{
token = tkOTHER;
}
break;
}
default: {
token = tkOTHER;
break;
}
}
#endif /* SQLITE_OMIT_TRIGGER */
zSql += nId-1;
}else{
/* Operators and special symbols */
token = tkOTHER;
}
break;
}
}
state = trans[state][token];
zSql++;
}
return state==0;
}
#ifndef SQLITE_OMIT_UTF16
/*
** This routine is the same as the sqlite3_complete() routine described
** above, except that the parameter is required to be UTF-16 encoded, not
** UTF-8.
*/
int sqlite3_complete16(const void *zSql){
sqlite3_value *pVal;
char const *zSql8;
int rc = 0;
pVal = sqlite3ValueNew();
sqlite3ValueSetStr(pVal, -1, zSql, SQLITE_UTF16NATIVE, SQLITE_STATIC);
zSql8 = sqlite3ValueText(pVal, SQLITE_UTF8);
if( zSql8 ){
rc = sqlite3_complete(zSql8);
}
sqlite3ValueFree(pVal);
return rc;
}
#endif /* SQLITE_OMIT_UTF16 */
#endif /* SQLITE_OMIT_COMPLETE */