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-rw-r--r--kopete/plugins/statistics/sqlite/expr.c1927
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diff --git a/kopete/plugins/statistics/sqlite/expr.c b/kopete/plugins/statistics/sqlite/expr.c
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--- a/kopete/plugins/statistics/sqlite/expr.c
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-/*
-** 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.
-**
-*************************************************************************
-** This file contains routines used for analyzing expressions and
-** for generating VDBE code that evaluates expressions in SQLite.
-**
-** $Id$
-*/
-#include "sqliteInt.h"
-#include <ctype.h>
-
-/*
-** Return the 'affinity' of the expression pExpr if any.
-**
-** If pExpr is a column, a reference to a column via an 'AS' alias,
-** or a sub-select with a column as the return value, then the
-** affinity of that column is returned. Otherwise, 0x00 is returned,
-** indicating no affinity for the expression.
-**
-** i.e. the WHERE clause expresssions in the following statements all
-** have an affinity:
-**
-** CREATE TABLE t1(a);
-** SELECT * FROM t1 WHERE a;
-** SELECT a AS b FROM t1 WHERE b;
-** SELECT * FROM t1 WHERE (select a from t1);
-*/
-char sqlite3ExprAffinity(Expr *pExpr){
- if( pExpr->op==TK_AS ){
- return sqlite3ExprAffinity(pExpr->pLeft);
- }
- if( pExpr->op==TK_SELECT ){
- return sqlite3ExprAffinity(pExpr->pSelect->pEList->a[0].pExpr);
- }
- return pExpr->affinity;
-}
-
-/*
-** Return the default collation sequence for the expression pExpr. If
-** there is no default collation type, return 0.
-*/
-CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
- CollSeq *pColl = 0;
- if( pExpr ){
- pColl = pExpr->pColl;
- if( pExpr->op==TK_AS && !pColl ){
- return sqlite3ExprCollSeq(pParse, pExpr->pLeft);
- }
- }
- if( sqlite3CheckCollSeq(pParse, pColl) ){
- pColl = 0;
- }
- return pColl;
-}
-
-/*
-** pExpr is the left operand of a comparison operator. aff2 is the
-** type affinity of the right operand. This routine returns the
-** type affinity that should be used for the comparison operator.
-*/
-char sqlite3CompareAffinity(Expr *pExpr, char aff2){
- char aff1 = sqlite3ExprAffinity(pExpr);
- if( aff1 && aff2 ){
- /* Both sides of the comparison are columns. If one has numeric or
- ** integer affinity, use that. Otherwise use no affinity.
- */
- if( aff1==SQLITE_AFF_INTEGER || aff2==SQLITE_AFF_INTEGER ){
- return SQLITE_AFF_INTEGER;
- }else if( aff1==SQLITE_AFF_NUMERIC || aff2==SQLITE_AFF_NUMERIC ){
- return SQLITE_AFF_NUMERIC;
- }else{
- return SQLITE_AFF_NONE;
- }
- }else if( !aff1 && !aff2 ){
- /* Neither side of the comparison is a column. Compare the
- ** results directly.
- */
- /* return SQLITE_AFF_NUMERIC; // Ticket #805 */
- return SQLITE_AFF_NONE;
- }else{
- /* One side is a column, the other is not. Use the columns affinity. */
- return (aff1 + aff2);
- }
-}
-
-/*
-** pExpr is a comparison operator. Return the type affinity that should
-** be applied to both operands prior to doing the comparison.
-*/
-static char comparisonAffinity(Expr *pExpr){
- char aff;
- assert( pExpr->op==TK_EQ || pExpr->op==TK_IN || pExpr->op==TK_LT ||
- pExpr->op==TK_GT || pExpr->op==TK_GE || pExpr->op==TK_LE ||
- pExpr->op==TK_NE );
- assert( pExpr->pLeft );
- aff = sqlite3ExprAffinity(pExpr->pLeft);
- if( pExpr->pRight ){
- aff = sqlite3CompareAffinity(pExpr->pRight, aff);
- }
- else if( pExpr->pSelect ){
- aff = sqlite3CompareAffinity(pExpr->pSelect->pEList->a[0].pExpr, aff);
- }
- else if( !aff ){
- aff = SQLITE_AFF_NUMERIC;
- }
- return aff;
-}
-
-/*
-** pExpr is a comparison expression, eg. '=', '<', IN(...) etc.
-** idx_affinity is the affinity of an indexed column. Return true
-** if the index with affinity idx_affinity may be used to implement
-** the comparison in pExpr.
-*/
-int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity){
- char aff = comparisonAffinity(pExpr);
- return
- (aff==SQLITE_AFF_NONE) ||
- (aff==SQLITE_AFF_NUMERIC && idx_affinity==SQLITE_AFF_INTEGER) ||
- (aff==SQLITE_AFF_INTEGER && idx_affinity==SQLITE_AFF_NUMERIC) ||
- (aff==idx_affinity);
-}
-
-/*
-** Return the P1 value that should be used for a binary comparison
-** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2.
-** If jumpIfNull is true, then set the low byte of the returned
-** P1 value to tell the opcode to jump if either expression
-** evaluates to NULL.
-*/
-static int binaryCompareP1(Expr *pExpr1, Expr *pExpr2, int jumpIfNull){
- char aff = sqlite3ExprAffinity(pExpr2);
- return (((int)sqlite3CompareAffinity(pExpr1, aff))<<8)+(jumpIfNull?1:0);
-}
-
-/*
-** Return a pointer to the collation sequence that should be used by
-** a binary comparison operator comparing pLeft and pRight.
-**
-** If the left hand expression has a collating sequence type, then it is
-** used. Otherwise the collation sequence for the right hand expression
-** is used, or the default (BINARY) if neither expression has a collating
-** type.
-*/
-static CollSeq* binaryCompareCollSeq(Parse *pParse, Expr *pLeft, Expr *pRight){
- CollSeq *pColl = sqlite3ExprCollSeq(pParse, pLeft);
- if( !pColl ){
- pColl = sqlite3ExprCollSeq(pParse, pRight);
- }
- return pColl;
-}
-
-/*
-** Generate code for a comparison operator.
-*/
-static int codeCompare(
- Parse *pParse, /* The parsing (and code generating) context */
- Expr *pLeft, /* The left operand */
- Expr *pRight, /* The right operand */
- int opcode, /* The comparison opcode */
- int dest, /* Jump here if true. */
- int jumpIfNull /* If true, jump if either operand is NULL */
-){
- int p1 = binaryCompareP1(pLeft, pRight, jumpIfNull);
- CollSeq *p3 = binaryCompareCollSeq(pParse, pLeft, pRight);
- return sqlite3VdbeOp3(pParse->pVdbe, opcode, p1, dest, (void*)p3, P3_COLLSEQ);
-}
-
-/*
-** Construct a new expression node and return a pointer to it. Memory
-** for this node is obtained from sqliteMalloc(). The calling function
-** is responsible for making sure the node eventually gets freed.
-*/
-Expr *sqlite3Expr(int op, Expr *pLeft, Expr *pRight, Token *pToken){
- Expr *pNew;
- pNew = sqliteMalloc( sizeof(Expr) );
- if( pNew==0 ){
- /* When malloc fails, we leak memory from pLeft and pRight */
- return 0;
- }
- pNew->op = op;
- pNew->pLeft = pLeft;
- pNew->pRight = pRight;
- if( pToken ){
- assert( pToken->dyn==0 );
- pNew->span = pNew->token = *pToken;
- }else if( pLeft && pRight ){
- sqlite3ExprSpan(pNew, &pLeft->span, &pRight->span);
- }
- return pNew;
-}
-
-/*
-** Join two expressions using an AND operator. If either expression is
-** NULL, then just return the other expression.
-*/
-Expr *sqlite3ExprAnd(Expr *pLeft, Expr *pRight){
- if( pLeft==0 ){
- return pRight;
- }else if( pRight==0 ){
- return pLeft;
- }else{
- return sqlite3Expr(TK_AND, pLeft, pRight, 0);
- }
-}
-
-/*
-** Set the Expr.span field of the given expression to span all
-** text between the two given tokens.
-*/
-void sqlite3ExprSpan(Expr *pExpr, Token *pLeft, Token *pRight){
- assert( pRight!=0 );
- assert( pLeft!=0 );
- if( !sqlite3_malloc_failed && pRight->z && pLeft->z ){
- assert( pLeft->dyn==0 || pLeft->z[pLeft->n]==0 );
- if( pLeft->dyn==0 && pRight->dyn==0 ){
- pExpr->span.z = pLeft->z;
- pExpr->span.n = pRight->n + Addr(pRight->z) - Addr(pLeft->z);
- }else{
- pExpr->span.z = 0;
- }
- }
-}
-
-/*
-** Construct a new expression node for a function with multiple
-** arguments.
-*/
-Expr *sqlite3ExprFunction(ExprList *pList, Token *pToken){
- Expr *pNew;
- pNew = sqliteMalloc( sizeof(Expr) );
- if( pNew==0 ){
- /* sqlite3ExprListDelete(pList); // Leak pList when malloc fails */
- return 0;
- }
- pNew->op = TK_FUNCTION;
- pNew->pList = pList;
- if( pToken ){
- assert( pToken->dyn==0 );
- pNew->token = *pToken;
- }else{
- pNew->token.z = 0;
- }
- pNew->span = pNew->token;
- return pNew;
-}
-
-/*
-** Assign a variable number to an expression that encodes a wildcard
-** in the original SQL statement.
-**
-** Wildcards consisting of a single "?" are assigned the next sequential
-** variable number.
-**
-** Wildcards of the form "?nnn" are assigned the number "nnn". We make
-** sure "nnn" is not too be to avoid a denial of service attack when
-** the SQL statement comes from an external source.
-**
-** Wildcards of the form ":aaa" or "$aaa" are assigned the same number
-** as the previous instance of the same wildcard. Or if this is the first
-** instance of the wildcard, the next sequenial variable number is
-** assigned.
-*/
-void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
- Token *pToken;
- if( pExpr==0 ) return;
- pToken = &pExpr->token;
- assert( pToken->n>=1 );
- assert( pToken->z!=0 );
- assert( pToken->z[0]!=0 );
- if( pToken->n==1 ){
- /* Wildcard of the form "?". Assign the next variable number */
- pExpr->iTable = ++pParse->nVar;
- }else if( pToken->z[0]=='?' ){
- /* Wildcard of the form "?nnn". Convert "nnn" to an integer and
- ** use it as the variable number */
- int i;
- pExpr->iTable = i = atoi(&pToken->z[1]);
- if( i<1 || i>SQLITE_MAX_VARIABLE_NUMBER ){
- sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
- SQLITE_MAX_VARIABLE_NUMBER);
- }
- if( i>pParse->nVar ){
- pParse->nVar = i;
- }
- }else{
- /* Wildcards of the form ":aaa" or "$aaa". Reuse the same variable
- ** number as the prior appearance of the same name, or if the name
- ** has never appeared before, reuse the same variable number
- */
- int i, n;
- n = pToken->n;
- for(i=0; i<pParse->nVarExpr; i++){
- Expr *pE;
- if( (pE = pParse->apVarExpr[i])!=0
- && pE->token.n==n
- && memcmp(pE->token.z, pToken->z, n)==0 ){
- pExpr->iTable = pE->iTable;
- break;
- }
- }
- if( i>=pParse->nVarExpr ){
- pExpr->iTable = ++pParse->nVar;
- if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){
- pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;
- pParse->apVarExpr = sqliteRealloc(pParse->apVarExpr,
- pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0]) );
- }
- if( !sqlite3_malloc_failed ){
- assert( pParse->apVarExpr!=0 );
- pParse->apVarExpr[pParse->nVarExpr++] = pExpr;
- }
- }
- }
-}
-
-/*
-** Recursively delete an expression tree.
-*/
-void sqlite3ExprDelete(Expr *p){
- if( p==0 ) return;
- if( p->span.dyn ) sqliteFree((char*)p->span.z);
- if( p->token.dyn ) sqliteFree((char*)p->token.z);
- sqlite3ExprDelete(p->pLeft);
- sqlite3ExprDelete(p->pRight);
- sqlite3ExprListDelete(p->pList);
- sqlite3SelectDelete(p->pSelect);
- sqliteFree(p);
-}
-
-
-/*
-** The following group of routines make deep copies of expressions,
-** expression lists, ID lists, and select statements. The copies can
-** be deleted (by being passed to their respective ...Delete() routines)
-** without effecting the originals.
-**
-** The expression list, ID, and source lists return by sqlite3ExprListDup(),
-** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded
-** by subsequent calls to sqlite*ListAppend() routines.
-**
-** Any tables that the SrcList might point to are not duplicated.
-*/
-Expr *sqlite3ExprDup(Expr *p){
- Expr *pNew;
- if( p==0 ) return 0;
- pNew = sqliteMallocRaw( sizeof(*p) );
- if( pNew==0 ) return 0;
- memcpy(pNew, p, sizeof(*pNew));
- if( p->token.z!=0 ){
- pNew->token.z = sqliteStrDup(p->token.z);
- pNew->token.dyn = 1;
- }else{
- assert( pNew->token.z==0 );
- }
- pNew->span.z = 0;
- pNew->pLeft = sqlite3ExprDup(p->pLeft);
- pNew->pRight = sqlite3ExprDup(p->pRight);
- pNew->pList = sqlite3ExprListDup(p->pList);
- pNew->pSelect = sqlite3SelectDup(p->pSelect);
- return pNew;
-}
-void sqlite3TokenCopy(Token *pTo, Token *pFrom){
- if( pTo->dyn ) sqliteFree((char*)pTo->z);
- if( pFrom->z ){
- pTo->n = pFrom->n;
- pTo->z = sqliteStrNDup(pFrom->z, pFrom->n);
- pTo->dyn = 1;
- }else{
- pTo->z = 0;
- }
-}
-ExprList *sqlite3ExprListDup(ExprList *p){
- ExprList *pNew;
- struct ExprList_item *pItem, *pOldItem;
- int i;
- if( p==0 ) return 0;
- pNew = sqliteMalloc( sizeof(*pNew) );
- if( pNew==0 ) return 0;
- pNew->nExpr = pNew->nAlloc = p->nExpr;
- pNew->a = pItem = sqliteMalloc( p->nExpr*sizeof(p->a[0]) );
- if( pItem==0 ){
- sqliteFree(pNew);
- return 0;
- }
- pOldItem = p->a;
- for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
- Expr *pNewExpr, *pOldExpr;
- pItem->pExpr = pNewExpr = sqlite3ExprDup(pOldExpr = pOldItem->pExpr);
- if( pOldExpr->span.z!=0 && pNewExpr ){
- /* Always make a copy of the span for top-level expressions in the
- ** expression list. The logic in SELECT processing that determines
- ** the names of columns in the result set needs this information */
- sqlite3TokenCopy(&pNewExpr->span, &pOldExpr->span);
- }
- assert( pNewExpr==0 || pNewExpr->span.z!=0
- || pOldExpr->span.z==0 || sqlite3_malloc_failed );
- pItem->zName = sqliteStrDup(pOldItem->zName);
- pItem->sortOrder = pOldItem->sortOrder;
- pItem->isAgg = pOldItem->isAgg;
- pItem->done = 0;
- }
- return pNew;
-}
-SrcList *sqlite3SrcListDup(SrcList *p){
- SrcList *pNew;
- int i;
- int nByte;
- if( p==0 ) return 0;
- nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
- pNew = sqliteMallocRaw( nByte );
- if( pNew==0 ) return 0;
- pNew->nSrc = pNew->nAlloc = p->nSrc;
- for(i=0; i<p->nSrc; i++){
- struct SrcList_item *pNewItem = &pNew->a[i];
- struct SrcList_item *pOldItem = &p->a[i];
- pNewItem->zDatabase = sqliteStrDup(pOldItem->zDatabase);
- pNewItem->zName = sqliteStrDup(pOldItem->zName);
- pNewItem->zAlias = sqliteStrDup(pOldItem->zAlias);
- pNewItem->jointype = pOldItem->jointype;
- pNewItem->iCursor = pOldItem->iCursor;
- pNewItem->pTab = 0;
- pNewItem->pSelect = sqlite3SelectDup(pOldItem->pSelect);
- pNewItem->pOn = sqlite3ExprDup(pOldItem->pOn);
- pNewItem->pUsing = sqlite3IdListDup(pOldItem->pUsing);
- }
- return pNew;
-}
-IdList *sqlite3IdListDup(IdList *p){
- IdList *pNew;
- int i;
- if( p==0 ) return 0;
- pNew = sqliteMallocRaw( sizeof(*pNew) );
- if( pNew==0 ) return 0;
- pNew->nId = pNew->nAlloc = p->nId;
- pNew->a = sqliteMallocRaw( p->nId*sizeof(p->a[0]) );
- if( pNew->a==0 ) return 0;
- for(i=0; i<p->nId; i++){
- struct IdList_item *pNewItem = &pNew->a[i];
- struct IdList_item *pOldItem = &p->a[i];
- pNewItem->zName = sqliteStrDup(pOldItem->zName);
- pNewItem->idx = pOldItem->idx;
- }
- return pNew;
-}
-Select *sqlite3SelectDup(Select *p){
- Select *pNew;
- if( p==0 ) return 0;
- pNew = sqliteMallocRaw( sizeof(*p) );
- if( pNew==0 ) return 0;
- pNew->isDistinct = p->isDistinct;
- pNew->pEList = sqlite3ExprListDup(p->pEList);
- pNew->pSrc = sqlite3SrcListDup(p->pSrc);
- pNew->pWhere = sqlite3ExprDup(p->pWhere);
- pNew->pGroupBy = sqlite3ExprListDup(p->pGroupBy);
- pNew->pHaving = sqlite3ExprDup(p->pHaving);
- pNew->pOrderBy = sqlite3ExprListDup(p->pOrderBy);
- pNew->op = p->op;
- pNew->pPrior = sqlite3SelectDup(p->pPrior);
- pNew->nLimit = p->nLimit;
- pNew->nOffset = p->nOffset;
- pNew->zSelect = 0;
- pNew->iLimit = -1;
- pNew->iOffset = -1;
- pNew->ppOpenTemp = 0;
- return pNew;
-}
-
-
-/*
-** Add a new element to the end of an expression list. If pList is
-** initially NULL, then create a new expression list.
-*/
-ExprList *sqlite3ExprListAppend(ExprList *pList, Expr *pExpr, Token *pName){
- if( pList==0 ){
- pList = sqliteMalloc( sizeof(ExprList) );
- if( pList==0 ){
- /* sqlite3ExprDelete(pExpr); // Leak memory if malloc fails */
- return 0;
- }
- assert( pList->nAlloc==0 );
- }
- if( pList->nAlloc<=pList->nExpr ){
- pList->nAlloc = pList->nAlloc*2 + 4;
- pList->a = sqliteRealloc(pList->a, pList->nAlloc*sizeof(pList->a[0]));
- if( pList->a==0 ){
- /* sqlite3ExprDelete(pExpr); // Leak memory if malloc fails */
- pList->nExpr = pList->nAlloc = 0;
- return pList;
- }
- }
- assert( pList->a!=0 );
- if( pExpr || pName ){
- struct ExprList_item *pItem = &pList->a[pList->nExpr++];
- memset(pItem, 0, sizeof(*pItem));
- pItem->pExpr = pExpr;
- pItem->zName = sqlite3NameFromToken(pName);
- }
- return pList;
-}
-
-/*
-** Delete an entire expression list.
-*/
-void sqlite3ExprListDelete(ExprList *pList){
- int i;
- struct ExprList_item *pItem;
- if( pList==0 ) return;
- assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );
- assert( pList->nExpr<=pList->nAlloc );
- for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
- sqlite3ExprDelete(pItem->pExpr);
- sqliteFree(pItem->zName);
- }
- sqliteFree(pList->a);
- sqliteFree(pList);
-}
-
-/*
-** Walk an expression tree. Return 1 if the expression is constant
-** and 0 if it involves variables.
-**
-** For the purposes of this function, a double-quoted string (ex: "abc")
-** is considered a variable but a single-quoted string (ex: 'abc') is
-** a constant.
-*/
-int sqlite3ExprIsConstant(Expr *p){
- switch( p->op ){
- case TK_ID:
- case TK_COLUMN:
- case TK_DOT:
- case TK_FUNCTION:
- return 0;
- case TK_NULL:
- case TK_STRING:
- case TK_BLOB:
- case TK_INTEGER:
- case TK_FLOAT:
- case TK_VARIABLE:
- return 1;
- default: {
- if( p->pLeft && !sqlite3ExprIsConstant(p->pLeft) ) return 0;
- if( p->pRight && !sqlite3ExprIsConstant(p->pRight) ) return 0;
- if( p->pList ){
- int i;
- for(i=0; i<p->pList->nExpr; i++){
- if( !sqlite3ExprIsConstant(p->pList->a[i].pExpr) ) return 0;
- }
- }
- return p->pLeft!=0 || p->pRight!=0 || (p->pList && p->pList->nExpr>0);
- }
- }
- return 0;
-}
-
-/*
-** If the given expression codes a constant integer that is small enough
-** to fit in a 32-bit integer, return 1 and put the value of the integer
-** in *pValue. If the expression is not an integer or if it is too big
-** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.
-*/
-int sqlite3ExprIsInteger(Expr *p, int *pValue){
- switch( p->op ){
- case TK_INTEGER: {
- if( sqlite3GetInt32(p->token.z, pValue) ){
- return 1;
- }
- break;
- }
- case TK_STRING: {
- const u8 *z = (u8*)p->token.z;
- int n = p->token.n;
- if( n>0 && z[0]=='-' ){ z++; n--; }
- while( n>0 && *z && isdigit(*z) ){ z++; n--; }
- if( n==0 && sqlite3GetInt32(p->token.z, pValue) ){
- return 1;
- }
- break;
- }
- case TK_UPLUS: {
- return sqlite3ExprIsInteger(p->pLeft, pValue);
- }
- case TK_UMINUS: {
- int v;
- if( sqlite3ExprIsInteger(p->pLeft, &v) ){
- *pValue = -v;
- return 1;
- }
- break;
- }
- default: break;
- }
- return 0;
-}
-
-/*
-** Return TRUE if the given string is a row-id column name.
-*/
-int sqlite3IsRowid(const char *z){
- if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1;
- if( sqlite3StrICmp(z, "ROWID")==0 ) return 1;
- if( sqlite3StrICmp(z, "OID")==0 ) return 1;
- return 0;
-}
-
-/*
-** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up
-** that name in the set of source tables in pSrcList and make the pExpr
-** expression node refer back to that source column. The following changes
-** are made to pExpr:
-**
-** pExpr->iDb Set the index in db->aDb[] of the database holding
-** the table.
-** pExpr->iTable Set to the cursor number for the table obtained
-** from pSrcList.
-** pExpr->iColumn Set to the column number within the table.
-** pExpr->op Set to TK_COLUMN.
-** pExpr->pLeft Any expression this points to is deleted
-** pExpr->pRight Any expression this points to is deleted.
-**
-** The pDbToken is the name of the database (the "X"). This value may be
-** NULL meaning that name is of the form Y.Z or Z. Any available database
-** can be used. The pTableToken is the name of the table (the "Y"). This
-** value can be NULL if pDbToken is also NULL. If pTableToken is NULL it
-** means that the form of the name is Z and that columns from any table
-** can be used.
-**
-** If the name cannot be resolved unambiguously, leave an error message
-** in pParse and return non-zero. Return zero on success.
-*/
-static int lookupName(
- Parse *pParse, /* The parsing context */
- Token *pDbToken, /* Name of the database containing table, or NULL */
- Token *pTableToken, /* Name of table containing column, or NULL */
- Token *pColumnToken, /* Name of the column. */
- SrcList *pSrcList, /* List of tables used to resolve column names */
- ExprList *pEList, /* List of expressions used to resolve "AS" */
- Expr *pExpr /* Make this EXPR node point to the selected column */
-){
- char *zDb = 0; /* Name of the database. The "X" in X.Y.Z */
- char *zTab = 0; /* Name of the table. The "Y" in X.Y.Z or Y.Z */
- char *zCol = 0; /* Name of the column. The "Z" */
- int i, j; /* Loop counters */
- int cnt = 0; /* Number of matching column names */
- int cntTab = 0; /* Number of matching table names */
- sqlite3 *db = pParse->db; /* The database */
-
- assert( pColumnToken && pColumnToken->z ); /* The Z in X.Y.Z cannot be NULL */
- zDb = sqlite3NameFromToken(pDbToken);
- zTab = sqlite3NameFromToken(pTableToken);
- zCol = sqlite3NameFromToken(pColumnToken);
- if( sqlite3_malloc_failed ){
- return 1; /* Leak memory (zDb and zTab) if malloc fails */
- }
- assert( zTab==0 || pEList==0 );
-
- pExpr->iTable = -1;
- for(i=0; i<pSrcList->nSrc; i++){
- struct SrcList_item *pItem = &pSrcList->a[i];
- Table *pTab = pItem->pTab;
- Column *pCol;
-
- if( pTab==0 ) continue;
- assert( pTab->nCol>0 );
- if( zTab ){
- if( pItem->zAlias ){
- char *zTabName = pItem->zAlias;
- if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
- }else{
- char *zTabName = pTab->zName;
- if( zTabName==0 || sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
- if( zDb!=0 && sqlite3StrICmp(db->aDb[pTab->iDb].zName, zDb)!=0 ){
- continue;
- }
- }
- }
- if( 0==(cntTab++) ){
- pExpr->iTable = pItem->iCursor;
- pExpr->iDb = pTab->iDb;
- }
- for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
- if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
- cnt++;
- pExpr->iTable = pItem->iCursor;
- pExpr->iDb = pTab->iDb;
- /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
- pExpr->iColumn = j==pTab->iPKey ? -1 : j;
- pExpr->affinity = pTab->aCol[j].affinity;
- pExpr->pColl = pTab->aCol[j].pColl;
- break;
- }
- }
- }
-
- /* If we have not already resolved the name, then maybe
- ** it is a new.* or old.* trigger argument reference
- */
- if( zDb==0 && zTab!=0 && cnt==0 && pParse->trigStack!=0 ){
- TriggerStack *pTriggerStack = pParse->trigStack;
- Table *pTab = 0;
- if( pTriggerStack->newIdx != -1 && sqlite3StrICmp("new", zTab) == 0 ){
- pExpr->iTable = pTriggerStack->newIdx;
- assert( pTriggerStack->pTab );
- pTab = pTriggerStack->pTab;
- }else if( pTriggerStack->oldIdx != -1 && sqlite3StrICmp("old", zTab) == 0 ){
- pExpr->iTable = pTriggerStack->oldIdx;
- assert( pTriggerStack->pTab );
- pTab = pTriggerStack->pTab;
- }
-
- if( pTab ){
- int j;
- Column *pCol = pTab->aCol;
-
- pExpr->iDb = pTab->iDb;
- cntTab++;
- for(j=0; j < pTab->nCol; j++, pCol++) {
- if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
- cnt++;
- pExpr->iColumn = j==pTab->iPKey ? -1 : j;
- pExpr->affinity = pTab->aCol[j].affinity;
- pExpr->pColl = pTab->aCol[j].pColl;
- break;
- }
- }
- }
- }
-
- /*
- ** Perhaps the name is a reference to the ROWID
- */
- if( cnt==0 && cntTab==1 && sqlite3IsRowid(zCol) ){
- cnt = 1;
- pExpr->iColumn = -1;
- pExpr->affinity = SQLITE_AFF_INTEGER;
- }
-
- /*
- ** If the input is of the form Z (not Y.Z or X.Y.Z) then the name Z
- ** might refer to an result-set alias. This happens, for example, when
- ** we are resolving names in the WHERE clause of the following command:
- **
- ** SELECT a+b AS x FROM table WHERE x<10;
- **
- ** In cases like this, replace pExpr with a copy of the expression that
- ** forms the result set entry ("a+b" in the example) and return immediately.
- ** Note that the expression in the result set should have already been
- ** resolved by the time the WHERE clause is resolved.
- */
- if( cnt==0 && pEList!=0 ){
- for(j=0; j<pEList->nExpr; j++){
- char *zAs = pEList->a[j].zName;
- if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){
- assert( pExpr->pLeft==0 && pExpr->pRight==0 );
- pExpr->op = TK_AS;
- pExpr->iColumn = j;
- pExpr->pLeft = sqlite3ExprDup(pEList->a[j].pExpr);
- sqliteFree(zCol);
- assert( zTab==0 && zDb==0 );
- return 0;
- }
- }
- }
-
- /*
- ** If X and Y are NULL (in other words if only the column name Z is
- ** supplied) and the value of Z is enclosed in double-quotes, then
- ** Z is a string literal if it doesn't match any column names. In that
- ** case, we need to return right away and not make any changes to
- ** pExpr.
- */
- if( cnt==0 && zTab==0 && pColumnToken->z[0]=='"' ){
- sqliteFree(zCol);
- return 0;
- }
-
- /*
- ** cnt==0 means there was not match. cnt>1 means there were two or
- ** more matches. Either way, we have an error.
- */
- if( cnt!=1 ){
- char *z = 0;
- char *zErr;
- zErr = cnt==0 ? "no such column: %s" : "ambiguous column name: %s";
- if( zDb ){
- sqlite3SetString(&z, zDb, ".", zTab, ".", zCol, 0);
- }else if( zTab ){
- sqlite3SetString(&z, zTab, ".", zCol, 0);
- }else{
- z = sqliteStrDup(zCol);
- }
- sqlite3ErrorMsg(pParse, zErr, z);
- sqliteFree(z);
- }
-
- /* Clean up and return
- */
- sqliteFree(zDb);
- sqliteFree(zTab);
- sqliteFree(zCol);
- sqlite3ExprDelete(pExpr->pLeft);
- pExpr->pLeft = 0;
- sqlite3ExprDelete(pExpr->pRight);
- pExpr->pRight = 0;
- pExpr->op = TK_COLUMN;
- sqlite3AuthRead(pParse, pExpr, pSrcList);
- return cnt!=1;
-}
-
-/*
-** This routine walks an expression tree and resolves references to
-** table columns. Nodes of the form ID.ID or ID resolve into an
-** index to the table in the table list and a column offset. The
-** Expr.opcode for such nodes is changed to TK_COLUMN. The Expr.iTable
-** value is changed to the index of the referenced table in pTabList
-** plus the "base" value. The base value will ultimately become the
-** VDBE cursor number for a cursor that is pointing into the referenced
-** table. The Expr.iColumn value is changed to the index of the column
-** of the referenced table. The Expr.iColumn value for the special
-** ROWID column is -1. Any INTEGER PRIMARY KEY column is tried as an
-** alias for ROWID.
-**
-** We also check for instances of the IN operator. IN comes in two
-** forms:
-**
-** expr IN (exprlist)
-** and
-** expr IN (SELECT ...)
-**
-** The first form is handled by creating a set holding the list
-** of allowed values. The second form causes the SELECT to generate
-** a temporary table.
-**
-** This routine also looks for scalar SELECTs that are part of an expression.
-** If it finds any, it generates code to write the value of that select
-** into a memory cell.
-**
-** Unknown columns or tables provoke an error. The function returns
-** the number of errors seen and leaves an error message on pParse->zErrMsg.
-*/
-int sqlite3ExprResolveIds(
- Parse *pParse, /* The parser context */
- SrcList *pSrcList, /* List of tables used to resolve column names */
- ExprList *pEList, /* List of expressions used to resolve "AS" */
- Expr *pExpr /* The expression to be analyzed. */
-){
- int i;
-
- if( pExpr==0 || pSrcList==0 ) return 0;
- for(i=0; i<pSrcList->nSrc; i++){
- assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab );
- }
- switch( pExpr->op ){
- /* Double-quoted strings (ex: "abc") are used as identifiers if
- ** possible. Otherwise they remain as strings. Single-quoted
- ** strings (ex: 'abc') are always string literals.
- */
- case TK_STRING: {
- if( pExpr->token.z[0]=='\'' ) break;
- /* Fall thru into the TK_ID case if this is a double-quoted string */
- }
- /* A lone identifier is the name of a columnd.
- */
- case TK_ID: {
- if( lookupName(pParse, 0, 0, &pExpr->token, pSrcList, pEList, pExpr) ){
- return 1;
- }
- break;
- }
-
- /* A table name and column name: ID.ID
- ** Or a database, table and column: ID.ID.ID
- */
- case TK_DOT: {
- Token *pColumn;
- Token *pTable;
- Token *pDb;
- Expr *pRight;
-
- pRight = pExpr->pRight;
- if( pRight->op==TK_ID ){
- pDb = 0;
- pTable = &pExpr->pLeft->token;
- pColumn = &pRight->token;
- }else{
- assert( pRight->op==TK_DOT );
- pDb = &pExpr->pLeft->token;
- pTable = &pRight->pLeft->token;
- pColumn = &pRight->pRight->token;
- }
- if( lookupName(pParse, pDb, pTable, pColumn, pSrcList, 0, pExpr) ){
- return 1;
- }
- break;
- }
-
- case TK_IN: {
- char affinity;
- Vdbe *v = sqlite3GetVdbe(pParse);
- KeyInfo keyInfo;
- int addr; /* Address of OP_OpenTemp instruction */
-
- if( v==0 ) return 1;
- if( sqlite3ExprResolveIds(pParse, pSrcList, pEList, pExpr->pLeft) ){
- return 1;
- }
- affinity = sqlite3ExprAffinity(pExpr->pLeft);
-
- /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
- ** expression it is handled the same way. A temporary table is
- ** filled with single-field index keys representing the results
- ** from the SELECT or the <exprlist>.
- **
- ** If the 'x' expression is a column value, or the SELECT...
- ** statement returns a column value, then the affinity of that
- ** column is used to build the index keys. If both 'x' and the
- ** SELECT... statement are columns, then numeric affinity is used
- ** if either column has NUMERIC or INTEGER affinity. If neither
- ** 'x' nor the SELECT... statement are columns, then numeric affinity
- ** is used.
- */
- pExpr->iTable = pParse->nTab++;
- addr = sqlite3VdbeAddOp(v, OP_OpenTemp, pExpr->iTable, 0);
- memset(&keyInfo, 0, sizeof(keyInfo));
- keyInfo.nField = 1;
- sqlite3VdbeAddOp(v, OP_SetNumColumns, pExpr->iTable, 1);
-
- if( pExpr->pSelect ){
- /* Case 1: expr IN (SELECT ...)
- **
- ** Generate code to write the results of the select into the temporary
- ** table allocated and opened above.
- */
- int iParm = pExpr->iTable + (((int)affinity)<<16);
- ExprList *pEList;
- assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
- sqlite3Select(pParse, pExpr->pSelect, SRT_Set, iParm, 0, 0, 0, 0);
- pEList = pExpr->pSelect->pEList;
- if( pEList && pEList->nExpr>0 ){
- keyInfo.aColl[0] = binaryCompareCollSeq(pParse, pExpr->pLeft,
- pEList->a[0].pExpr);
- }
- }else if( pExpr->pList ){
- /* Case 2: expr IN (exprlist)
- **
- ** For each expression, build an index key from the evaluation and
- ** store it in the temporary table. If <expr> is a column, then use
- ** that columns affinity when building index keys. If <expr> is not
- ** a column, use numeric affinity.
- */
- int i;
- if( !affinity ){
- affinity = SQLITE_AFF_NUMERIC;
- }
- keyInfo.aColl[0] = pExpr->pLeft->pColl;
-
- /* Loop through each expression in <exprlist>. */
- for(i=0; i<pExpr->pList->nExpr; i++){
- Expr *pE2 = pExpr->pList->a[i].pExpr;
-
- /* Check that the expression is constant and valid. */
- if( !sqlite3ExprIsConstant(pE2) ){
- sqlite3ErrorMsg(pParse,
- "right-hand side of IN operator must be constant");
- return 1;
- }
- if( sqlite3ExprCheck(pParse, pE2, 0, 0) ){
- return 1;
- }
-
- /* Evaluate the expression and insert it into the temp table */
- sqlite3ExprCode(pParse, pE2);
- sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1);
- sqlite3VdbeAddOp(v, OP_String8, 0, 0);
- sqlite3VdbeAddOp(v, OP_PutStrKey, pExpr->iTable, 0);
- }
- }
- sqlite3VdbeChangeP3(v, addr, (void *)&keyInfo, P3_KEYINFO);
-
- break;
- }
-
- case TK_SELECT: {
- /* This has to be a scalar SELECT. Generate code to put the
- ** value of this select in a memory cell and record the number
- ** of the memory cell in iColumn.
- */
- pExpr->iColumn = pParse->nMem++;
- if(sqlite3Select(pParse, pExpr->pSelect, SRT_Mem,pExpr->iColumn,0,0,0,0)){
- return 1;
- }
- break;
- }
-
- /* For all else, just recursively walk the tree */
- default: {
- if( pExpr->pLeft
- && sqlite3ExprResolveIds(pParse, pSrcList, pEList, pExpr->pLeft) ){
- return 1;
- }
- if( pExpr->pRight
- && sqlite3ExprResolveIds(pParse, pSrcList, pEList, pExpr->pRight) ){
- return 1;
- }
- if( pExpr->pList ){
- int i;
- ExprList *pList = pExpr->pList;
- for(i=0; i<pList->nExpr; i++){
- Expr *pArg = pList->a[i].pExpr;
- if( sqlite3ExprResolveIds(pParse, pSrcList, pEList, pArg) ){
- return 1;
- }
- }
- }
- }
- }
- return 0;
-}
-
-/*
-** pExpr is a node that defines a function of some kind. It might
-** be a syntactic function like "count(x)" or it might be a function
-** that implements an operator, like "a LIKE b".
-**
-** This routine makes *pzName point to the name of the function and
-** *pnName hold the number of characters in the function name.
-*/
-static void getFunctionName(Expr *pExpr, const char **pzName, int *pnName){
- switch( pExpr->op ){
- case TK_FUNCTION: {
- *pzName = pExpr->token.z;
- *pnName = pExpr->token.n;
- break;
- }
- case TK_LIKE: {
- *pzName = "like";
- *pnName = 4;
- break;
- }
- case TK_GLOB: {
- *pzName = "glob";
- *pnName = 4;
- break;
- }
- default: {
- *pzName = "can't happen";
- *pnName = 12;
- break;
- }
- }
-}
-
-/*
-** Error check the functions in an expression. Make sure all
-** function names are recognized and all functions have the correct
-** number of arguments. Leave an error message in pParse->zErrMsg
-** if anything is amiss. Return the number of errors.
-**
-** if pIsAgg is not null and this expression is an aggregate function
-** (like count(*) or max(value)) then write a 1 into *pIsAgg.
-*/
-int sqlite3ExprCheck(Parse *pParse, Expr *pExpr, int allowAgg, int *pIsAgg){
- int nErr = 0;
- if( pExpr==0 ) return 0;
- switch( pExpr->op ){
- case TK_GLOB:
- case TK_LIKE:
- case TK_FUNCTION: {
- int n = pExpr->pList ? pExpr->pList->nExpr : 0; /* Number of arguments */
- int no_such_func = 0; /* True if no such function exists */
- int wrong_num_args = 0; /* True if wrong number of arguments */
- int is_agg = 0; /* True if is an aggregate function */
- int i;
- int nId; /* Number of characters in function name */
- const char *zId; /* The function name. */
- FuncDef *pDef;
- int enc = pParse->db->enc;
-
- getFunctionName(pExpr, &zId, &nId);
- pDef = sqlite3FindFunction(pParse->db, zId, nId, n, enc, 0);
- if( pDef==0 ){
- pDef = sqlite3FindFunction(pParse->db, zId, nId, -1, enc, 0);
- if( pDef==0 ){
- no_such_func = 1;
- }else{
- wrong_num_args = 1;
- }
- }else{
- is_agg = pDef->xFunc==0;
- }
- if( is_agg && !allowAgg ){
- sqlite3ErrorMsg(pParse, "misuse of aggregate function %.*s()", nId, zId);
- nErr++;
- is_agg = 0;
- }else if( no_such_func ){
- sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId);
- nErr++;
- }else if( wrong_num_args ){
- sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()",
- nId, zId);
- nErr++;
- }
- if( is_agg ){
- pExpr->op = TK_AGG_FUNCTION;
- if( pIsAgg ) *pIsAgg = 1;
- }
- for(i=0; nErr==0 && i<n; i++){
- nErr = sqlite3ExprCheck(pParse, pExpr->pList->a[i].pExpr,
- allowAgg && !is_agg, pIsAgg);
- }
- /* FIX ME: Compute pExpr->affinity based on the expected return
- ** type of the function
- */
- }
- default: {
- if( pExpr->pLeft ){
- nErr = sqlite3ExprCheck(pParse, pExpr->pLeft, allowAgg, pIsAgg);
- }
- if( nErr==0 && pExpr->pRight ){
- nErr = sqlite3ExprCheck(pParse, pExpr->pRight, allowAgg, pIsAgg);
- }
- if( nErr==0 && pExpr->pList ){
- int n = pExpr->pList->nExpr;
- int i;
- for(i=0; nErr==0 && i<n; i++){
- Expr *pE2 = pExpr->pList->a[i].pExpr;
- nErr = sqlite3ExprCheck(pParse, pE2, allowAgg, pIsAgg);
- }
- }
- break;
- }
- }
- return nErr;
-}
-
-/*
-** Call sqlite3ExprResolveIds() followed by sqlite3ExprCheck().
-**
-** This routine is provided as a convenience since it is very common
-** to call ResolveIds() and Check() back to back.
-*/
-int sqlite3ExprResolveAndCheck(
- Parse *pParse, /* The parser context */
- SrcList *pSrcList, /* List of tables used to resolve column names */
- ExprList *pEList, /* List of expressions used to resolve "AS" */
- Expr *pExpr, /* The expression to be analyzed. */
- int allowAgg, /* True to allow aggregate expressions */
- int *pIsAgg /* Set to TRUE if aggregates are found */
-){
- if( pExpr==0 ) return 0;
- if( sqlite3ExprResolveIds(pParse,pSrcList,pEList,pExpr) ){
- return 1;
- }
- return sqlite3ExprCheck(pParse, pExpr, allowAgg, pIsAgg);
-}
-
-/*
-** Generate an instruction that will put the integer describe by
-** text z[0..n-1] on the stack.
-*/
-static void codeInteger(Vdbe *v, const char *z, int n){
- int i;
- if( sqlite3GetInt32(z, &i) ){
- sqlite3VdbeAddOp(v, OP_Integer, i, 0);
- }else if( sqlite3FitsIn64Bits(z) ){
- sqlite3VdbeOp3(v, OP_Integer, 0, 0, z, n);
- }else{
- sqlite3VdbeOp3(v, OP_Real, 0, 0, z, n);
- }
-}
-
-/*
-** Generate code into the current Vdbe to evaluate the given
-** expression and leave the result on the top of stack.
-**
-** This code depends on the fact that certain token values (ex: TK_EQ)
-** are the same as opcode values (ex: OP_Eq) that implement the corresponding
-** operation. Special comments in vdbe.c and the mkopcodeh.awk script in
-** the make process cause these values to align. Assert()s in the code
-** below verify that the numbers are aligned correctly.
-*/
-void sqlite3ExprCode(Parse *pParse, Expr *pExpr){
- Vdbe *v = pParse->pVdbe;
- int op;
- if( v==0 || pExpr==0 ) return;
- op = pExpr->op;
- switch( op ){
- case TK_COLUMN: {
- if( pParse->useAgg ){
- sqlite3VdbeAddOp(v, OP_AggGet, 0, pExpr->iAgg);
- }else if( pExpr->iColumn>=0 ){
- sqlite3VdbeAddOp(v, OP_Column, pExpr->iTable, pExpr->iColumn);
-#ifndef NDEBUG
- if( pExpr->span.z && pExpr->span.n>0 && pExpr->span.n<100 ){
- VdbeComment((v, "# %T", &pExpr->span));
- }
-#endif
- }else{
- sqlite3VdbeAddOp(v, OP_Recno, pExpr->iTable, 0);
- }
- break;
- }
- case TK_INTEGER: {
- codeInteger(v, pExpr->token.z, pExpr->token.n);
- break;
- }
- case TK_FLOAT:
- case TK_STRING: {
- assert( TK_FLOAT==OP_Real );
- assert( TK_STRING==OP_String8 );
- sqlite3VdbeOp3(v, op, 0, 0, pExpr->token.z, pExpr->token.n);
- sqlite3VdbeDequoteP3(v, -1);
- break;
- }
- case TK_BLOB: {
- assert( TK_BLOB==OP_HexBlob );
- sqlite3VdbeOp3(v, op, 0, 0, pExpr->token.z+1, pExpr->token.n-1);
- sqlite3VdbeDequoteP3(v, -1);
- break;
- }
- case TK_NULL: {
- sqlite3VdbeAddOp(v, OP_String8, 0, 0);
- break;
- }
- case TK_VARIABLE: {
- sqlite3VdbeAddOp(v, OP_Variable, pExpr->iTable, 0);
- if( pExpr->token.n>1 ){
- sqlite3VdbeChangeP3(v, -1, pExpr->token.z, pExpr->token.n);
- }
- break;
- }
- case TK_LT:
- case TK_LE:
- case TK_GT:
- case TK_GE:
- case TK_NE:
- case TK_EQ: {
- assert( TK_LT==OP_Lt );
- assert( TK_LE==OP_Le );
- assert( TK_GT==OP_Gt );
- assert( TK_GE==OP_Ge );
- assert( TK_EQ==OP_Eq );
- assert( TK_NE==OP_Ne );
- sqlite3ExprCode(pParse, pExpr->pLeft);
- sqlite3ExprCode(pParse, pExpr->pRight);
- codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, 0, 0);
- break;
- }
- case TK_AND:
- case TK_OR:
- case TK_PLUS:
- case TK_STAR:
- case TK_MINUS:
- case TK_REM:
- case TK_BITAND:
- case TK_BITOR:
- case TK_SLASH:
- case TK_LSHIFT:
- case TK_RSHIFT:
- case TK_CONCAT: {
- assert( TK_AND==OP_And );
- assert( TK_OR==OP_Or );
- assert( TK_PLUS==OP_Add );
- assert( TK_MINUS==OP_Subtract );
- assert( TK_REM==OP_Remainder );
- assert( TK_BITAND==OP_BitAnd );
- assert( TK_BITOR==OP_BitOr );
- assert( TK_SLASH==OP_Divide );
- assert( TK_LSHIFT==OP_ShiftLeft );
- assert( TK_RSHIFT==OP_ShiftRight );
- assert( TK_CONCAT==OP_Concat );
- sqlite3ExprCode(pParse, pExpr->pLeft);
- sqlite3ExprCode(pParse, pExpr->pRight);
- sqlite3VdbeAddOp(v, op, 0, 0);
- break;
- }
- case TK_UMINUS: {
- Expr *pLeft = pExpr->pLeft;
- assert( pLeft );
- if( pLeft->op==TK_FLOAT || pLeft->op==TK_INTEGER ){
- Token *p = &pLeft->token;
- char *z = sqliteMalloc( p->n + 2 );
- sprintf(z, "-%.*s", p->n, p->z);
- if( pLeft->op==TK_FLOAT ){
- sqlite3VdbeOp3(v, OP_Real, 0, 0, z, p->n+1);
- }else{
- codeInteger(v, z, p->n+1);
- }
- sqliteFree(z);
- break;
- }
- /* Fall through into TK_NOT */
- }
- case TK_BITNOT:
- case TK_NOT: {
- assert( TK_BITNOT==OP_BitNot );
- assert( TK_NOT==OP_Not );
- sqlite3ExprCode(pParse, pExpr->pLeft);
- sqlite3VdbeAddOp(v, op, 0, 0);
- break;
- }
- case TK_ISNULL:
- case TK_NOTNULL: {
- int dest;
- assert( TK_ISNULL==OP_IsNull );
- assert( TK_NOTNULL==OP_NotNull );
- sqlite3VdbeAddOp(v, OP_Integer, 1, 0);
- sqlite3ExprCode(pParse, pExpr->pLeft);
- dest = sqlite3VdbeCurrentAddr(v) + 2;
- sqlite3VdbeAddOp(v, op, 1, dest);
- sqlite3VdbeAddOp(v, OP_AddImm, -1, 0);
- break;
- }
- case TK_AGG_FUNCTION: {
- sqlite3VdbeAddOp(v, OP_AggGet, 0, pExpr->iAgg);
- break;
- }
- case TK_GLOB:
- case TK_LIKE:
- case TK_FUNCTION: {
- ExprList *pList = pExpr->pList;
- int nExpr = pList ? pList->nExpr : 0;
- FuncDef *pDef;
- int nId;
- const char *zId;
- int p2 = 0;
- int i;
- u8 enc = pParse->db->enc;
- CollSeq *pColl = 0;
- getFunctionName(pExpr, &zId, &nId);
- pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, enc, 0);
- assert( pDef!=0 );
- nExpr = sqlite3ExprCodeExprList(pParse, pList);
- for(i=0; i<nExpr && i<32; i++){
- if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){
- p2 |= (1<<i);
- }
- if( pDef->needCollSeq && !pColl ){
- pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr);
- }
- }
- if( pDef->needCollSeq ){
- if( !pColl ) pColl = pParse->db->pDfltColl;
- sqlite3VdbeOp3(v, OP_CollSeq, 0, 0, (char *)pColl, P3_COLLSEQ);
- }
- sqlite3VdbeOp3(v, OP_Function, nExpr, p2, (char*)pDef, P3_FUNCDEF);
- break;
- }
- case TK_SELECT: {
- sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
- VdbeComment((v, "# load subquery result"));
- break;
- }
- case TK_IN: {
- int addr;
- char affinity;
-
- /* Figure out the affinity to use to create a key from the results
- ** of the expression. affinityStr stores a static string suitable for
- ** P3 of OP_MakeRecord.
- */
- affinity = comparisonAffinity(pExpr);
-
- sqlite3VdbeAddOp(v, OP_Integer, 1, 0);
-
- /* Code the <expr> from "<expr> IN (...)". The temporary table
- ** pExpr->iTable contains the values that make up the (...) set.
- */
- sqlite3ExprCode(pParse, pExpr->pLeft);
- addr = sqlite3VdbeCurrentAddr(v);
- sqlite3VdbeAddOp(v, OP_NotNull, -1, addr+4); /* addr + 0 */
- sqlite3VdbeAddOp(v, OP_Pop, 2, 0);
- sqlite3VdbeAddOp(v, OP_String8, 0, 0);
- sqlite3VdbeAddOp(v, OP_Goto, 0, addr+7);
- sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1); /* addr + 4 */
- sqlite3VdbeAddOp(v, OP_Found, pExpr->iTable, addr+7);
- sqlite3VdbeAddOp(v, OP_AddImm, -1, 0); /* addr + 6 */
-
- break;
- }
- case TK_BETWEEN: {
- Expr *pLeft = pExpr->pLeft;
- struct ExprList_item *pLItem = pExpr->pList->a;
- Expr *pRight = pLItem->pExpr;
- sqlite3ExprCode(pParse, pLeft);
- sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
- sqlite3ExprCode(pParse, pRight);
- codeCompare(pParse, pLeft, pRight, OP_Ge, 0, 0);
- sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
- pLItem++;
- pRight = pLItem->pExpr;
- sqlite3ExprCode(pParse, pRight);
- codeCompare(pParse, pLeft, pRight, OP_Le, 0, 0);
- sqlite3VdbeAddOp(v, OP_And, 0, 0);
- break;
- }
- case TK_UPLUS:
- case TK_AS: {
- sqlite3ExprCode(pParse, pExpr->pLeft);
- break;
- }
- case TK_CASE: {
- int expr_end_label;
- int jumpInst;
- int addr;
- int nExpr;
- int i;
- ExprList *pEList;
- struct ExprList_item *aListelem;
-
- assert(pExpr->pList);
- assert((pExpr->pList->nExpr % 2) == 0);
- assert(pExpr->pList->nExpr > 0);
- pEList = pExpr->pList;
- aListelem = pEList->a;
- nExpr = pEList->nExpr;
- expr_end_label = sqlite3VdbeMakeLabel(v);
- if( pExpr->pLeft ){
- sqlite3ExprCode(pParse, pExpr->pLeft);
- }
- for(i=0; i<nExpr; i=i+2){
- sqlite3ExprCode(pParse, aListelem[i].pExpr);
- if( pExpr->pLeft ){
- sqlite3VdbeAddOp(v, OP_Dup, 1, 1);
- jumpInst = codeCompare(pParse, pExpr->pLeft, aListelem[i].pExpr,
- OP_Ne, 0, 1);
- sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
- }else{
- jumpInst = sqlite3VdbeAddOp(v, OP_IfNot, 1, 0);
- }
- sqlite3ExprCode(pParse, aListelem[i+1].pExpr);
- sqlite3VdbeAddOp(v, OP_Goto, 0, expr_end_label);
- addr = sqlite3VdbeCurrentAddr(v);
- sqlite3VdbeChangeP2(v, jumpInst, addr);
- }
- if( pExpr->pLeft ){
- sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
- }
- if( pExpr->pRight ){
- sqlite3ExprCode(pParse, pExpr->pRight);
- }else{
- sqlite3VdbeAddOp(v, OP_String8, 0, 0);
- }
- sqlite3VdbeResolveLabel(v, expr_end_label);
- break;
- }
- case TK_RAISE: {
- if( !pParse->trigStack ){
- sqlite3ErrorMsg(pParse,
- "RAISE() may only be used within a trigger-program");
- return;
- }
- if( pExpr->iColumn!=OE_Ignore ){
- assert( pExpr->iColumn==OE_Rollback ||
- pExpr->iColumn == OE_Abort ||
- pExpr->iColumn == OE_Fail );
- sqlite3VdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn,
- pExpr->token.z, pExpr->token.n);
- sqlite3VdbeDequoteP3(v, -1);
- } else {
- assert( pExpr->iColumn == OE_Ignore );
- sqlite3VdbeAddOp(v, OP_ContextPop, 0, 0);
- sqlite3VdbeAddOp(v, OP_Goto, 0, pParse->trigStack->ignoreJump);
- VdbeComment((v, "# raise(IGNORE)"));
- }
- }
- break;
- }
-}
-
-/*
-** Generate code that pushes the value of every element of the given
-** expression list onto the stack.
-**
-** Return the number of elements pushed onto the stack.
-*/
-int sqlite3ExprCodeExprList(
- Parse *pParse, /* Parsing context */
- ExprList *pList /* The expression list to be coded */
-){
- struct ExprList_item *pItem;
- int i, n;
- Vdbe *v;
- if( pList==0 ) return 0;
- v = sqlite3GetVdbe(pParse);
- n = pList->nExpr;
- for(pItem=pList->a, i=0; i<n; i++, pItem++){
- sqlite3ExprCode(pParse, pItem->pExpr);
- }
- return n;
-}
-
-/*
-** Generate code for a boolean expression such that a jump is made
-** to the label "dest" if the expression is true but execution
-** continues straight thru if the expression is false.
-**
-** If the expression evaluates to NULL (neither true nor false), then
-** take the jump if the jumpIfNull flag is true.
-**
-** This code depends on the fact that certain token values (ex: TK_EQ)
-** are the same as opcode values (ex: OP_Eq) that implement the corresponding
-** operation. Special comments in vdbe.c and the mkopcodeh.awk script in
-** the make process cause these values to align. Assert()s in the code
-** below verify that the numbers are aligned correctly.
-*/
-void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
- Vdbe *v = pParse->pVdbe;
- int op = 0;
- if( v==0 || pExpr==0 ) return;
- op = pExpr->op;
- switch( op ){
- case TK_AND: {
- int d2 = sqlite3VdbeMakeLabel(v);
- sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2, !jumpIfNull);
- sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
- sqlite3VdbeResolveLabel(v, d2);
- break;
- }
- case TK_OR: {
- sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
- sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
- break;
- }
- case TK_NOT: {
- sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
- break;
- }
- case TK_LT:
- case TK_LE:
- case TK_GT:
- case TK_GE:
- case TK_NE:
- case TK_EQ: {
- assert( TK_LT==OP_Lt );
- assert( TK_LE==OP_Le );
- assert( TK_GT==OP_Gt );
- assert( TK_GE==OP_Ge );
- assert( TK_EQ==OP_Eq );
- assert( TK_NE==OP_Ne );
- sqlite3ExprCode(pParse, pExpr->pLeft);
- sqlite3ExprCode(pParse, pExpr->pRight);
- codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, dest, jumpIfNull);
- break;
- }
- case TK_ISNULL:
- case TK_NOTNULL: {
- assert( TK_ISNULL==OP_IsNull );
- assert( TK_NOTNULL==OP_NotNull );
- sqlite3ExprCode(pParse, pExpr->pLeft);
- sqlite3VdbeAddOp(v, op, 1, dest);
- break;
- }
- case TK_BETWEEN: {
- /* The expression "x BETWEEN y AND z" is implemented as:
- **
- ** 1 IF (x < y) GOTO 3
- ** 2 IF (x <= z) GOTO <dest>
- ** 3 ...
- */
- int addr;
- Expr *pLeft = pExpr->pLeft;
- Expr *pRight = pExpr->pList->a[0].pExpr;
- sqlite3ExprCode(pParse, pLeft);
- sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
- sqlite3ExprCode(pParse, pRight);
- addr = codeCompare(pParse, pLeft, pRight, OP_Lt, 0, !jumpIfNull);
-
- pRight = pExpr->pList->a[1].pExpr;
- sqlite3ExprCode(pParse, pRight);
- codeCompare(pParse, pLeft, pRight, OP_Le, dest, jumpIfNull);
-
- sqlite3VdbeAddOp(v, OP_Integer, 0, 0);
- sqlite3VdbeChangeP2(v, addr, sqlite3VdbeCurrentAddr(v));
- sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
- break;
- }
- default: {
- sqlite3ExprCode(pParse, pExpr);
- sqlite3VdbeAddOp(v, OP_If, jumpIfNull, dest);
- break;
- }
- }
-}
-
-/*
-** Generate code for a boolean expression such that a jump is made
-** to the label "dest" if the expression is false but execution
-** continues straight thru if the expression is true.
-**
-** If the expression evaluates to NULL (neither true nor false) then
-** jump if jumpIfNull is true or fall through if jumpIfNull is false.
-*/
-void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
- Vdbe *v = pParse->pVdbe;
- int op = 0;
- if( v==0 || pExpr==0 ) return;
-
- /* The value of pExpr->op and op are related as follows:
- **
- ** pExpr->op op
- ** --------- ----------
- ** TK_ISNULL OP_NotNull
- ** TK_NOTNULL OP_IsNull
- ** TK_NE OP_Eq
- ** TK_EQ OP_Ne
- ** TK_GT OP_Le
- ** TK_LE OP_Gt
- ** TK_GE OP_Lt
- ** TK_LT OP_Ge
- **
- ** For other values of pExpr->op, op is undefined and unused.
- ** The value of TK_ and OP_ constants are arranged such that we
- ** can compute the mapping above using the following expression.
- ** Assert()s verify that the computation is correct.
- */
- op = ((pExpr->op+(TK_ISNULL&1))^1)-(TK_ISNULL&1);
-
- /* Verify correct alignment of TK_ and OP_ constants
- */
- assert( pExpr->op!=TK_ISNULL || op==OP_NotNull );
- assert( pExpr->op!=TK_NOTNULL || op==OP_IsNull );
- assert( pExpr->op!=TK_NE || op==OP_Eq );
- assert( pExpr->op!=TK_EQ || op==OP_Ne );
- assert( pExpr->op!=TK_LT || op==OP_Ge );
- assert( pExpr->op!=TK_LE || op==OP_Gt );
- assert( pExpr->op!=TK_GT || op==OP_Le );
- assert( pExpr->op!=TK_GE || op==OP_Lt );
-
- switch( pExpr->op ){
- case TK_AND: {
- sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
- sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
- break;
- }
- case TK_OR: {
- int d2 = sqlite3VdbeMakeLabel(v);
- sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, !jumpIfNull);
- sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
- sqlite3VdbeResolveLabel(v, d2);
- break;
- }
- case TK_NOT: {
- sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
- break;
- }
- case TK_LT:
- case TK_LE:
- case TK_GT:
- case TK_GE:
- case TK_NE:
- case TK_EQ: {
- sqlite3ExprCode(pParse, pExpr->pLeft);
- sqlite3ExprCode(pParse, pExpr->pRight);
- codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, dest, jumpIfNull);
- break;
- }
- case TK_ISNULL:
- case TK_NOTNULL: {
- sqlite3ExprCode(pParse, pExpr->pLeft);
- sqlite3VdbeAddOp(v, op, 1, dest);
- break;
- }
- case TK_BETWEEN: {
- /* The expression is "x BETWEEN y AND z". It is implemented as:
- **
- ** 1 IF (x >= y) GOTO 3
- ** 2 GOTO <dest>
- ** 3 IF (x > z) GOTO <dest>
- */
- int addr;
- Expr *pLeft = pExpr->pLeft;
- Expr *pRight = pExpr->pList->a[0].pExpr;
- sqlite3ExprCode(pParse, pLeft);
- sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
- sqlite3ExprCode(pParse, pRight);
- addr = sqlite3VdbeCurrentAddr(v);
- codeCompare(pParse, pLeft, pRight, OP_Ge, addr+3, !jumpIfNull);
-
- sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
- sqlite3VdbeAddOp(v, OP_Goto, 0, dest);
- pRight = pExpr->pList->a[1].pExpr;
- sqlite3ExprCode(pParse, pRight);
- codeCompare(pParse, pLeft, pRight, OP_Gt, dest, jumpIfNull);
- break;
- }
- default: {
- sqlite3ExprCode(pParse, pExpr);
- sqlite3VdbeAddOp(v, OP_IfNot, jumpIfNull, dest);
- break;
- }
- }
-}
-
-/*
-** Do a deep comparison of two expression trees. Return TRUE (non-zero)
-** if they are identical and return FALSE if they differ in any way.
-*/
-int sqlite3ExprCompare(Expr *pA, Expr *pB){
- int i;
- if( pA==0 ){
- return pB==0;
- }else if( pB==0 ){
- return 0;
- }
- if( pA->op!=pB->op ) return 0;
- if( !sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 0;
- if( !sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 0;
- if( pA->pList ){
- if( pB->pList==0 ) return 0;
- if( pA->pList->nExpr!=pB->pList->nExpr ) return 0;
- for(i=0; i<pA->pList->nExpr; i++){
- if( !sqlite3ExprCompare(pA->pList->a[i].pExpr, pB->pList->a[i].pExpr) ){
- return 0;
- }
- }
- }else if( pB->pList ){
- return 0;
- }
- if( pA->pSelect || pB->pSelect ) return 0;
- if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 0;
- if( pA->token.z ){
- if( pB->token.z==0 ) return 0;
- if( pB->token.n!=pA->token.n ) return 0;
- if( sqlite3StrNICmp(pA->token.z, pB->token.z, pB->token.n)!=0 ) return 0;
- }
- return 1;
-}
-
-/*
-** Add a new element to the pParse->aAgg[] array and return its index.
-*/
-static int appendAggInfo(Parse *pParse){
- if( (pParse->nAgg & 0x7)==0 ){
- int amt = pParse->nAgg + 8;
- AggExpr *aAgg = sqliteRealloc(pParse->aAgg, amt*sizeof(pParse->aAgg[0]));
- if( aAgg==0 ){
- return -1;
- }
- pParse->aAgg = aAgg;
- }
- memset(&pParse->aAgg[pParse->nAgg], 0, sizeof(pParse->aAgg[0]));
- return pParse->nAgg++;
-}
-
-/*
-** Analyze the given expression looking for aggregate functions and
-** for variables that need to be added to the pParse->aAgg[] array.
-** Make additional entries to the pParse->aAgg[] array as necessary.
-**
-** This routine should only be called after the expression has been
-** analyzed by sqlite3ExprResolveIds() and sqlite3ExprCheck().
-**
-** If errors are seen, leave an error message in zErrMsg and return
-** the number of errors.
-*/
-int sqlite3ExprAnalyzeAggregates(Parse *pParse, Expr *pExpr){
- int i;
- AggExpr *aAgg;
- int nErr = 0;
-
- if( pExpr==0 ) return 0;
- switch( pExpr->op ){
- case TK_COLUMN: {
- aAgg = pParse->aAgg;
- for(i=0; i<pParse->nAgg; i++){
- if( aAgg[i].isAgg ) continue;
- if( aAgg[i].pExpr->iTable==pExpr->iTable
- && aAgg[i].pExpr->iColumn==pExpr->iColumn ){
- break;
- }
- }
- if( i>=pParse->nAgg ){
- i = appendAggInfo(pParse);
- if( i<0 ) return 1;
- pParse->aAgg[i].isAgg = 0;
- pParse->aAgg[i].pExpr = pExpr;
- }
- pExpr->iAgg = i;
- break;
- }
- case TK_AGG_FUNCTION: {
- aAgg = pParse->aAgg;
- for(i=0; i<pParse->nAgg; i++){
- if( !aAgg[i].isAgg ) continue;
- if( sqlite3ExprCompare(aAgg[i].pExpr, pExpr) ){
- break;
- }
- }
- if( i>=pParse->nAgg ){
- u8 enc = pParse->db->enc;
- i = appendAggInfo(pParse);
- if( i<0 ) return 1;
- pParse->aAgg[i].isAgg = 1;
- pParse->aAgg[i].pExpr = pExpr;
- pParse->aAgg[i].pFunc = sqlite3FindFunction(pParse->db,
- pExpr->token.z, pExpr->token.n,
- pExpr->pList ? pExpr->pList->nExpr : 0, enc, 0);
- }
- pExpr->iAgg = i;
- break;
- }
- default: {
- if( pExpr->pLeft ){
- nErr = sqlite3ExprAnalyzeAggregates(pParse, pExpr->pLeft);
- }
- if( nErr==0 && pExpr->pRight ){
- nErr = sqlite3ExprAnalyzeAggregates(pParse, pExpr->pRight);
- }
- if( nErr==0 && pExpr->pList ){
- int n = pExpr->pList->nExpr;
- int i;
- for(i=0; nErr==0 && i<n; i++){
- nErr = sqlite3ExprAnalyzeAggregates(pParse, pExpr->pList->a[i].pExpr);
- }
- }
- break;
- }
- }
- return nErr;
-}
-
-/*
-** Locate a user function given a name, a number of arguments and a flag
-** indicating whether the function prefers UTF-16 over UTF-8. Return a
-** pointer to the FuncDef structure that defines that function, or return
-** NULL if the function does not exist.
-**
-** If the createFlag argument is true, then a new (blank) FuncDef
-** structure is created and liked into the "db" structure if a
-** no matching function previously existed. When createFlag is true
-** and the nArg parameter is -1, then only a function that accepts
-** any number of arguments will be returned.
-**
-** If createFlag is false and nArg is -1, then the first valid
-** function found is returned. A function is valid if either xFunc
-** or xStep is non-zero.
-**
-** If createFlag is false, then a function with the required name and
-** number of arguments may be returned even if the eTextRep flag does not
-** match that requested.
-*/
-FuncDef *sqlite3FindFunction(
- sqlite3 *db, /* An open database */
- const char *zName, /* Name of the function. Not null-terminated */
- int nName, /* Number of characters in the name */
- int nArg, /* Number of arguments. -1 means any number */
- u8 enc, /* Preferred text encoding */
- int createFlag /* Create new entry if true and does not otherwise exist */
-){
- FuncDef *p; /* Iterator variable */
- FuncDef *pFirst; /* First function with this name */
- FuncDef *pBest = 0; /* Best match found so far */
- int bestmatch = 0;
-
-
- assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
- if( nArg<-1 ) nArg = -1;
-
- pFirst = (FuncDef*)sqlite3HashFind(&db->aFunc, zName, nName);
- for(p=pFirst; p; p=p->pNext){
- /* During the search for the best function definition, bestmatch is set
- ** as follows to indicate the quality of the match with the definition
- ** pointed to by pBest:
- **
- ** 0: pBest is NULL. No match has been found.
- ** 1: A variable arguments function that prefers UTF-8 when a UTF-16
- ** encoding is requested, or vice versa.
- ** 2: A variable arguments function that uses UTF-16BE when UTF-16LE is
- ** requested, or vice versa.
- ** 3: A variable arguments function using the same text encoding.
- ** 4: A function with the exact number of arguments requested that
- ** prefers UTF-8 when a UTF-16 encoding is requested, or vice versa.
- ** 5: A function with the exact number of arguments requested that
- ** prefers UTF-16LE when UTF-16BE is requested, or vice versa.
- ** 6: An exact match.
- **
- ** A larger value of 'matchqual' indicates a more desirable match.
- */
- if( p->nArg==-1 || p->nArg==nArg || nArg==-1 ){
- int match = 1; /* Quality of this match */
- if( p->nArg==nArg || nArg==-1 ){
- match = 4;
- }
- if( enc==p->iPrefEnc ){
- match += 2;
- }
- else if( (enc==SQLITE_UTF16LE && p->iPrefEnc==SQLITE_UTF16BE) ||
- (enc==SQLITE_UTF16BE && p->iPrefEnc==SQLITE_UTF16LE) ){
- match += 1;
- }
-
- if( match>bestmatch ){
- pBest = p;
- bestmatch = match;
- }
- }
- }
-
- /* If the createFlag parameter is true, and the seach did not reveal an
- ** exact match for the name, number of arguments and encoding, then add a
- ** new entry to the hash table and return it.
- */
- if( createFlag && bestmatch<6 &&
- (pBest = sqliteMalloc(sizeof(*pBest)+nName+1)) ){
- pBest->nArg = nArg;
- pBest->pNext = pFirst;
- pBest->zName = (char*)&pBest[1];
- pBest->iPrefEnc = enc;
- memcpy(pBest->zName, zName, nName);
- pBest->zName[nName] = 0;
- sqlite3HashInsert(&db->aFunc, pBest->zName, nName, (void*)pBest);
- }
-
- if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
- return pBest;
- }
- return 0;
-}