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Move a few things around to make building without the parser easier. (CVS 2479)

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FossilOrigin-Name: 5fadb464eb77b4b998d8555f83401769960ea904
This commit is contained in:
danielk1977
2005-05-24 12:01:00 +00:00
parent b71090fdfb
commit fd9a0a45a7
11 changed files with 239 additions and 209 deletions
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103
src/expr.c
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@@ -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 1.200 2005/05/23 17:26:51 drh Exp $
** $Id: expr.c,v 1.201 2005/05/24 12:01:02 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
@@ -2049,104 +2049,3 @@ int sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){
walkExprTree(pExpr, analyzeAggregate, pNC);
return pNC->pParse->nErr - 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;
if( pBest==sqlite3HashInsert(&db->aFunc,pBest->zName,nName,(void*)pBest) ){
sqliteFree(pBest);
return 0;
}
}
if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
return pBest;
}
return 0;
}