/*
** Create new user-defined functions. The sqlite_create_function()
** routine creates a regular function and sqlite_create_aggregate()
** creates an aggregate function.
**
** Passing a NULL xFunc argument or NULL xStep and xFinalize arguments
** disables the function. Calling sqlite_create_function() with the
** same name and number of arguments as a prior call to
** sqlite_create_aggregate() disables the prior call to
** sqlite_create_aggregate(), and vice versa.
**
** If nArg is -1 it means that this function will accept any number
** of arguments, including 0. The maximum allowed value of nArg is 127.
*/
int sqlite_create_function(
sqlite *db, /* Add the function to this database connection */
const char *zName, /* Name of the function to add */
int nArg, /* Number of arguments */
void (*xFunc)(sqlite_func*,int,const char**), /* The implementation */
void *pUserData /* User data */
){
FuncDef *p;
int nName;
if( db==0 || zName==0 || sqliteSafetyCheck(db) ) return 1;
if( nArg<-1 || nArg>127 ) return 1;
nName = strlen(zName);
if( nName>255 ) return 1;
p = sqliteFindFunction(db, zName, nName, nArg, 1);
if( p==0 ) return 1;
p->xFunc = xFunc;
p->xStep = 0;
p->xFinalize = 0;
p->pUserData = pUserData;
return 0;
}
/*
** 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 sqliteExprResolveIds() and sqliteExprCheck().
**
** If errors are seen, leave an error message in zErrMsg and return
** the number of errors.
*/
int sqliteExprAnalyzeAggregates(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( sqliteExprCompare(aAgg[i].pExpr, pExpr) ){
break;
}
}
if( i>=pParse->nAgg ){
i = appendAggInfo(pParse);
if( i<0 ) return 1;
pParse->aAgg[i].isAgg = 1;
pParse->aAgg[i].pExpr = pExpr;
pParse->aAgg[i].pFunc = sqliteFindFunction(pParse->db,
pExpr->token.z, pExpr->token.n,
pExpr->pList ? pExpr->pList->nExpr : 0, 0);
}
pExpr->iAgg = i;
break;
}
default: {
if( pExpr->pLeft ){
nErr = sqliteExprAnalyzeAggregates(pParse, pExpr->pLeft);
}
if( nErr==0 && pExpr->pRight ){
nErr = sqliteExprAnalyzeAggregates(pParse, pExpr->pRight);
}
if( nErr==0 && pExpr->pList ){
int n = pExpr->pList->nExpr;
int i;
for(i=0; nErr==0 && i<n; i++){
nErr = sqliteExprAnalyzeAggregates(pParse, pExpr->pList->a[i].pExpr);
}
}
break;
}
}
return nErr;
}
/*
** 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 sqliteExprCheck(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;
getFunctionName(pExpr, &zId, &nId);
pDef = sqliteFindFunction(pParse->db, zId, nId, n, 0);
if( pDef==0 ){
pDef = sqliteFindFunction(pParse->db, zId, nId, -1, 0);
if( pDef==0 ){
no_such_func = 1;
}else{
wrong_num_args = 1;
}
}else{
is_agg = pDef->xFunc==0;
}
if( is_agg && !allowAgg ){
sqliteErrorMsg(pParse, "misuse of aggregate function %.*s()", nId, zId);
nErr++;
is_agg = 0;
}else if( no_such_func ){
sqliteErrorMsg(pParse, "no such function: %.*s", nId, zId);
nErr++;
}else if( wrong_num_args ){
sqliteErrorMsg(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 = sqliteExprCheck(pParse, pExpr->pList->a[i].pExpr,
allowAgg && !is_agg, pIsAgg);
}
if( pDef==0 ){
/* Already reported an error */
}else if( pDef->dataType>=0 ){
if( pDef->dataType<n ){
pExpr->dataType =
sqliteExprType(pExpr->pList->a[pDef->dataType].pExpr);
}else{
pExpr->dataType = SQLITE_SO_NUM;
}
}else if( pDef->dataType==SQLITE_ARGS ){
pDef->dataType = SQLITE_SO_TEXT;
for(i=0; i<n; i++){
if( sqliteExprType(pExpr->pList->a[i].pExpr)==SQLITE_SO_NUM ){
pExpr->dataType = SQLITE_SO_NUM;
break;
}
}
}else if( pDef->dataType==SQLITE_NUMERIC ){
pExpr->dataType = SQLITE_SO_NUM;
}else{
pExpr->dataType = SQLITE_SO_TEXT;
}
}
default: {
if( pExpr->pLeft ){
nErr = sqliteExprCheck(pParse, pExpr->pLeft, allowAgg, pIsAgg);
}
if( nErr==0 && pExpr->pRight ){
nErr = sqliteExprCheck(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 = sqliteExprCheck(pParse, pE2, allowAgg, pIsAgg);
}
}
break;
}
}
return nErr;
}
/*
** Generate code into the current Vdbe to evaluate the given
** expression and leave the result on the top of stack.
*/
void sqliteExprCode(Parse *pParse, Expr *pExpr){
Vdbe *v = pParse->pVdbe;
int op;
if( v==0 || pExpr==0 ) return;
switch( pExpr->op ){
case TK_PLUS: op = OP_Add; break;
case TK_MINUS: op = OP_Subtract; break;
case TK_STAR: op = OP_Multiply; break;
case TK_SLASH: op = OP_Divide; break;
case TK_AND: op = OP_And; break;
case TK_OR: op = OP_Or; break;
case TK_LT: op = OP_Lt; break;
case TK_LE: op = OP_Le; break;
case TK_GT: op = OP_Gt; break;
case TK_GE: op = OP_Ge; break;
case TK_NE: op = OP_Ne; break;
case TK_EQ: op = OP_Eq; break;
case TK_ISNULL: op = OP_IsNull; break;
case TK_NOTNULL: op = OP_NotNull; break;
case TK_NOT: op = OP_Not; break;
case TK_UMINUS: op = OP_Negative; break;
case TK_BITAND: op = OP_BitAnd; break;
case TK_BITOR: op = OP_BitOr; break;
case TK_BITNOT: op = OP_BitNot; break;
case TK_LSHIFT: op = OP_ShiftLeft; break;
case TK_RSHIFT: op = OP_ShiftRight; break;
case TK_REM: op = OP_Remainder; break;
default: break;
}
switch( pExpr->op ){
case TK_COLUMN: {
if( pParse->useAgg ){
sqliteVdbeAddOp(v, OP_AggGet, 0, pExpr->iAgg);
}else if( pExpr->iColumn>=0 ){
sqliteVdbeAddOp(v, OP_Column, pExpr->iTable, pExpr->iColumn);
}else{
sqliteVdbeAddOp(v, OP_Recno, pExpr->iTable, 0);
}
break;
}
case TK_STRING:
case TK_FLOAT:
case TK_INTEGER: {
if( pExpr->op==TK_INTEGER && sqliteFitsIn32Bits(pExpr->token.z) ){
sqliteVdbeAddOp(v, OP_Integer, atoi(pExpr->token.z), 0);
}else{
sqliteVdbeAddOp(v, OP_String, 0, 0);
}
assert( pExpr->token.z );
sqliteVdbeChangeP3(v, -1, pExpr->token.z, pExpr->token.n);
sqliteVdbeDequoteP3(v, -1);
break;
}
case TK_NULL: {
sqliteVdbeAddOp(v, OP_String, 0, 0);
break;
}
case TK_VARIABLE: {
sqliteVdbeAddOp(v, OP_Variable, pExpr->iTable, 0);
break;
}
case TK_LT:
case TK_LE:
case TK_GT:
case TK_GE:
case TK_NE:
case TK_EQ: {
if( pParse->db->file_format>=4 && sqliteExprType(pExpr)==SQLITE_SO_TEXT ){
op += 6; /* Convert numeric opcodes to text opcodes */
}
/* Fall through into the next case */
}
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: {
sqliteExprCode(pParse, pExpr->pLeft);
sqliteExprCode(pParse, pExpr->pRight);
sqliteVdbeAddOp(v, op, 0, 0);
break;
}
case TK_LSHIFT:
case TK_RSHIFT: {
sqliteExprCode(pParse, pExpr->pRight);
sqliteExprCode(pParse, pExpr->pLeft);
sqliteVdbeAddOp(v, op, 0, 0);
break;
}
case TK_CONCAT: {
sqliteExprCode(pParse, pExpr->pLeft);
sqliteExprCode(pParse, pExpr->pRight);
sqliteVdbeAddOp(v, OP_Concat, 2, 0);
break;
}
case TK_UMINUS: {
assert( pExpr->pLeft );
if( pExpr->pLeft->op==TK_FLOAT || pExpr->pLeft->op==TK_INTEGER ){
Token *p = &pExpr->pLeft->token;
char *z = sqliteMalloc( p->n + 2 );
sprintf(z, "-%.*s", p->n, p->z);
if( pExpr->pLeft->op==TK_INTEGER && sqliteFitsIn32Bits(z) ){
sqliteVdbeAddOp(v, OP_Integer, atoi(z), 0);
}else{
sqliteVdbeAddOp(v, OP_String, 0, 0);
}
sqliteVdbeChangeP3(v, -1, z, p->n+1);
sqliteFree(z);
break;
}
/* Fall through into TK_NOT */
}
case TK_BITNOT:
case TK_NOT: {
sqliteExprCode(pParse, pExpr->pLeft);
sqliteVdbeAddOp(v, op, 0, 0);
break;
}
case TK_ISNULL:
case TK_NOTNULL: {
int dest;
sqliteVdbeAddOp(v, OP_Integer, 1, 0);
sqliteExprCode(pParse, pExpr->pLeft);
dest = sqliteVdbeCurrentAddr(v) + 2;
sqliteVdbeAddOp(v, op, 1, dest);
sqliteVdbeAddOp(v, OP_AddImm, -1, 0);
break;
}
case TK_AGG_FUNCTION: {
sqliteVdbeAddOp(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;
getFunctionName(pExpr, &zId, &nId);
pDef = sqliteFindFunction(pParse->db, zId, nId, nExpr, 0);
assert( pDef!=0 );
nExpr = sqliteExprCodeExprList(pParse, pList, pDef->includeTypes);
sqliteVdbeOp3(v, OP_Function, nExpr, 0, (char*)pDef, P3_POINTER);
break;
}
case TK_SELECT: {
sqliteVdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
break;
}
case TK_IN: {
int addr;
sqliteVdbeAddOp(v, OP_Integer, 1, 0);
sqliteExprCode(pParse, pExpr->pLeft);
addr = sqliteVdbeCurrentAddr(v);
sqliteVdbeAddOp(v, OP_NotNull, -1, addr+4);
sqliteVdbeAddOp(v, OP_Pop, 1, 0);
sqliteVdbeAddOp(v, OP_String, 0, 0);
sqliteVdbeAddOp(v, OP_Goto, 0, addr+6);
if( pExpr->pSelect ){
sqliteVdbeAddOp(v, OP_Found, pExpr->iTable, addr+6);
}else{
sqliteVdbeAddOp(v, OP_SetFound, pExpr->iTable, addr+6);
}
sqliteVdbeAddOp(v, OP_AddImm, -1, 0);
break;
}
case TK_BETWEEN: {
sqliteExprCode(pParse, pExpr->pLeft);
sqliteVdbeAddOp(v, OP_Dup, 0, 0);
sqliteExprCode(pParse, pExpr->pList->a[0].pExpr);
sqliteVdbeAddOp(v, OP_Ge, 0, 0);
sqliteVdbeAddOp(v, OP_Pull, 1, 0);
sqliteExprCode(pParse, pExpr->pList->a[1].pExpr);
sqliteVdbeAddOp(v, OP_Le, 0, 0);
sqliteVdbeAddOp(v, OP_And, 0, 0);
break;
}
case TK_UPLUS:
case TK_AS: {
sqliteExprCode(pParse, pExpr->pLeft);
break;
}
case TK_CASE: {
int expr_end_label;
int jumpInst;
int addr;
int nExpr;
int i;
assert(pExpr->pList);
assert((pExpr->pList->nExpr % 2) == 0);
assert(pExpr->pList->nExpr > 0);
nExpr = pExpr->pList->nExpr;
expr_end_label = sqliteVdbeMakeLabel(v);
if( pExpr->pLeft ){
sqliteExprCode(pParse, pExpr->pLeft);
}
for(i=0; i<nExpr; i=i+2){
sqliteExprCode(pParse, pExpr->pList->a[i].pExpr);
if( pExpr->pLeft ){
sqliteVdbeAddOp(v, OP_Dup, 1, 1);
jumpInst = sqliteVdbeAddOp(v, OP_Ne, 1, 0);
sqliteVdbeAddOp(v, OP_Pop, 1, 0);
}else{
jumpInst = sqliteVdbeAddOp(v, OP_IfNot, 1, 0);
}
sqliteExprCode(pParse, pExpr->pList->a[i+1].pExpr);
sqliteVdbeAddOp(v, OP_Goto, 0, expr_end_label);
addr = sqliteVdbeCurrentAddr(v);
sqliteVdbeChangeP2(v, jumpInst, addr);
}
if( pExpr->pLeft ){
sqliteVdbeAddOp(v, OP_Pop, 1, 0);
}
if( pExpr->pRight ){
sqliteExprCode(pParse, pExpr->pRight);
}else{
sqliteVdbeAddOp(v, OP_String, 0, 0);
}
sqliteVdbeResolveLabel(v, expr_end_label);
break;
}
case TK_RAISE: {
if( !pParse->trigStack ){
sqliteErrorMsg(pParse,
"RAISE() may only be used within a trigger-program");
pParse->nErr++;
return;
}
if( pExpr->iColumn == OE_Rollback ||
pExpr->iColumn == OE_Abort ||
pExpr->iColumn == OE_Fail ){
sqliteVdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn,
pExpr->token.z, pExpr->token.n);
sqliteVdbeDequoteP3(v, -1);
} else {
assert( pExpr->iColumn == OE_Ignore );
sqliteVdbeOp3(v, OP_Goto, 0, pParse->trigStack->ignoreJump,
"(IGNORE jump)", 0);
}
}
break;
}
}