diff options
Diffstat (limited to 'src/expr.c')
| -rw-r--r-- | src/expr.c | 103 |
1 files changed, 70 insertions, 33 deletions
diff --git a/src/expr.c b/src/expr.c index b3ba9f47f..dd2a8cef3 100644 --- a/src/expr.c +++ b/src/expr.c @@ -12,7 +12,7 @@ ** This file contains routines used for analyzing expressions and ** for generating VDBE code that evaluates expressions in SQLite. ** -** $Id: expr.c,v 1.134 2004/06/05 10:22:17 danielk1977 Exp $ +** $Id: expr.c,v 1.135 2004/06/06 09:44:04 danielk1977 Exp $ */ #include "sqliteInt.h" #include <ctype.h> @@ -968,11 +968,12 @@ int sqlite3ExprCheck(Parse *pParse, Expr *pExpr, int allowAgg, int *pIsAgg){ int nId; /* Number of characters in function name */ const char *zId; /* The function name. */ FuncDef *pDef; + int iPrefEnc = (pParse->db->enc==TEXT_Utf8)?0:1; getFunctionName(pExpr, &zId, &nId); - pDef = sqlite3FindFunction(pParse->db, zId, nId, n, 0); + pDef = sqlite3FindFunction(pParse->db, zId, nId, n, iPrefEnc, 0); if( pDef==0 ){ - pDef = sqlite3FindFunction(pParse->db, zId, nId, -1, 0); + pDef = sqlite3FindFunction(pParse->db, zId, nId, -1, iPrefEnc, 0); if( pDef==0 ){ no_such_func = 1; }else{ @@ -1233,12 +1234,15 @@ void sqlite3ExprCode(Parse *pParse, Expr *pExpr){ const char *zId; int p2 = 0; int i; + int iPrefEnc = (pParse->db->enc==TEXT_Utf8)?0:1; getFunctionName(pExpr, &zId, &nId); - pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, 0); + pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, iPrefEnc, 0); assert( pDef!=0 ); nExpr = sqlite3ExprCodeExprList(pParse, pList); for(i=0; i<nExpr && i<32; i++){ - p2 &= (1<<i); + if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){ + p2 |= (1<<i); + } } sqlite3VdbeOp3(v, OP_Function, nExpr, p2, (char*)pDef, P3_FUNCDEF); break; @@ -1645,13 +1649,14 @@ int sqlite3ExprAnalyzeAggregates(Parse *pParse, Expr *pExpr){ } } if( i>=pParse->nAgg ){ + int iPrefEnc = (pParse->db->enc==TEXT_Utf8)?0:1; 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, 0); + pExpr->pList ? pExpr->pList->nExpr : 0, iPrefEnc, 0); } pExpr->iAgg = i; break; @@ -1677,9 +1682,10 @@ int sqlite3ExprAnalyzeAggregates(Parse *pParse, Expr *pExpr){ } /* -** Locate a user function given a name and a number of arguments. -** Return a pointer to the FuncDef structure that defines that -** function, or return NULL if the function does not exist. +** 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 @@ -1690,39 +1696,70 @@ int sqlite3ExprAnalyzeAggregates(Parse *pParse, Expr *pExpr){ ** 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( sqlite *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 */ + int eTextRep, /* True to retrieve UTF-16 versions. */ int createFlag /* Create new entry if true and does not otherwise exist */ ){ - FuncDef *pFirst, *p, *pMaybe; - pFirst = p = (FuncDef*)sqlite3HashFind(&db->aFunc, zName, nName); - if( p && !createFlag && nArg<0 ){ - while( p && p->xFunc==0 && p->xStep==0 ){ p = p->pNext; } - return p; - } - pMaybe = 0; - while( p && p->nArg!=nArg ){ - if( p->nArg<0 && !createFlag && (p->xFunc || p->xStep) ) pMaybe = p; - p = p->pNext; - } - if( p && !createFlag && p->xFunc==0 && p->xStep==0 ){ - return 0; + FuncDef *p; /* Iterator variable */ + FuncDef *pFirst; /* First function with this name */ + FuncDef *pBest = 0; /* Best match found so far */ + int matchqual = 0; + + /* Normalize argument values to simplify comparisons below. */ + if( eTextRep ) eTextRep = 1; + if( nArg<-1 ) nArg = -1; + + pFirst = (FuncDef*)sqlite3HashFind(&db->aFunc, zName, nName); + for(p=pFirst; p; p=p->pNext){ + if( 1 || p->xFunc || p->xStep ){ + if( p->nArg==nArg && p->iPrefEnc==eTextRep ){ + /* A perfect match. */ + pBest = p; + matchqual = 4; + break; + } + if( p->nArg==nArg ){ + /* Number of arguments matches, but not the text encoding */ + pBest = p; + matchqual = 3; + } + else if( (p->nArg<0) || (nArg<0) ){ + if( matchqual<2 && p->iPrefEnc==eTextRep ){ + /* Matched a varargs function with correct text encoding */ + pBest = p; + matchqual = 2; + } + if( matchqual<1 ){ + /* Matched a varargs function with incorrect text encoding */ + pBest = p; + matchqual = 1; + } + } + } } - if( p==0 && pMaybe ){ - assert( createFlag==0 ); - return pMaybe; + + if( createFlag && matchqual<4 && + (pBest = sqliteMalloc(sizeof(*pBest)+nName+1)) ){ + pBest->nArg = nArg; + pBest->pNext = pFirst; + pBest->zName = (char*)&pBest[1]; + memcpy(pBest->zName, zName, nName); + pBest->zName[nName] = 0; + sqlite3HashInsert(&db->aFunc, pBest->zName, nName, (void*)pBest); } - if( p==0 && createFlag && (p = sqliteMalloc(sizeof(*p)+nName+1))!=0 ){ - p->nArg = nArg; - p->pNext = pFirst; - p->zName = (char*)&p[1]; - memcpy(p->zName, zName, nName); - p->zName[nName] = 0; - sqlite3HashInsert(&db->aFunc, p->zName, nName, (void*)p); + + if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){ + return pBest; } - return p; + return 0; } + |