ifmxdb.c

一个简单的数据库管理工具

SetDbNulls(DbInfo_t *pDbInfo)
{
    if(pDbInfo->rlen==SQL_NULL_DATA && pDbInfo->pValue) {
	DebugHTML(__FILE__,__LINE__,3,"Fetched a Null");
	memset(pDbInfo->pValue,0,pDbInfo->iLen);
    }
        switch (pDbInfo->iColType)
        {
	    case SQL_DECIMAL:
	    case SQL_DOUBLE:
	    case SQL_REAL:
	    case SQL_INTEGER:
	    case SQL_SMALLINT:
		if((pDbInfo->iScale)==0) {
		    char *p;
		    for(p=pDbInfo->pValue;*p;p++)if(*p=='.')*p=0;
		}
        }
    return(eTrue);
}

/*
/* Get the Next Available CursorIndex from
/* the gaCDA array.
 */
static eBoolean_t
GetCursorIndex(int *piCursorIndex)
{
    static int siCursorIndex;
    int iStart, i;

    for(i=0, iStart=siCursorIndex
	    ;i==0 || (iStart != siCursorIndex && i>0)
	    ;i++, siCursorIndex = (siCursorIndex+1)%MAX_CURSORS)
    {
	/* the gbaOpen array simply lets me know when
	/* a cursor has been opened or closed so that
	/* in this routine I can re-use cursors!
	 */
	if( gbaOpen[siCursorIndex]==eFalse ) {
	    (*piCursorIndex) = siCursorIndex;
	    return(eTrue);
	}
    }
    MsgPush("Exceeded Maximum Cursors");
    return(eFalse);
}

/*
/* Describe the BIND Variables...
/*    this is much simplified since the parsing of the SQL
/*    string itself is handled in the PrepareParameters() function
/*    which was a hack of the origional decrbindvars...
 */
static eBoolean_t
DescribeBindVars(SQLWEB_CURSOR *pCursor)
{
    int iParamCnt=1;
    DbInfo_t *pDbInfo;

    for( pDbInfo=l_ffirst(pCursor->lBind);
	 pDbInfo;
	 pDbInfo=l_fnext(pCursor->lBind))
    {
	RETCODE rc;
	if( !pDbInfo->pValue) {
	     pDbInfo->pValue = DupBuf("");
	     pDbInfo->rlen = SQL_NULL_DATA;
	}
	else if( !*pDbInfo->pValue) {
	     pDbInfo->rlen = SQL_NULL_DATA;
	}
	else pDbInfo->rlen = SQL_NTS;

	/* bug fix ... */
	pDbInfo->rlen = SQL_NTS;
	/* bug fix ... */

	rc=SQLBindParameter( gaCDA[pCursor->iCursorIndex]
		    ,iParamCnt++
		    ,SQL_PARAM_INPUT
		    ,SQL_C_CHAR /* SQL_C_CHAR */
		    ,SQL_CHAR /* SQL_CHAR */
		    ,pDbInfo->iLen+1
		    ,0
		    ,pDbInfo->pValue /* &pDbInfo->pValue[0] */
		    ,pDbInfo->iLen+1
		    ,&pDbInfo->rlen
		    );
	if(rc!=SQL_SUCCESS && rc!=SQL_SUCCESS_WITH_INFO) {
	    PushDBErr(gaLDA[pCursor->pLDA->iLdaIndex]
		     ,gaCDA[pCursor->iCursorIndex]
		     ,"SQLBindParameter failed."
		     );
	    MsgPush("s='?',b=%x",pDbInfo->pValue);
	    return(eFalse);
	}
	DebugHTML(__FILE__,__LINE__,2,"Describe:Bound(%d: %s)",iParamCnt-1,pDbInfo->pValue);
    }
    return(eTrue);
}

/*
/* Describe the SELECT Variables...
 */
static eBoolean_t
DescribeSelectVars(SQLWEB_CURSOR *pCursor)
{
    SWORD NumCols, Col;
    RETCODE rc;
    UCHAR sColName [ MAX_ITEM_BUFFER_SIZE ];
    SWORD iColNameSize = sizeof(sColName)
	    ,iColType
	    ,iScale
	    ,iNullable
	;
    UDWORD iLength;
    char *pBuf;
    DbInfo_t *pDbInfo;

    rc=SQLNumResultCols(gaCDA[pCursor->iCursorIndex], &NumCols);
    if(rc!=SQL_SUCCESS && rc!=SQL_SUCCESS_WITH_INFO) {
	PushDBErr(gaLDA[pCursor->pLDA->iLdaIndex]
		 ,gaCDA[pCursor->iCursorIndex]
		 ,"SQLNumResultCols failed."
		 );
	return(eFalse);
    }

    if(NumCols!=0) {
	gbaOpen[pCursor->iCursorIndex]=pCursor->bOpen=eTrue;
    }

    /* Describe each select-list item.
     */
    for(Col=1;Col<=NumCols;Col++) {
	rc=SQLDescribeCol(gaCDA[pCursor->iCursorIndex]
			,Col
			,sColName
			,(SWORD)sizeof(sColName)
			,&iColNameSize
			,&iColType
			,&iLength
			,&iScale
			,&iNullable
			);
	if(rc!=SQL_SUCCESS && rc!=SQL_SUCCESS_WITH_INFO) {
	    PushDBErr(gaLDA[pCursor->pLDA->iLdaIndex]
		 ,gaCDA[pCursor->iCursorIndex]
		 ,"SQLDescribe failed."
		 );
	    return(eFalse);
        }
	sColName[iColNameSize]=0;

	DebugHTML(__FILE__,__LINE__,2,"DbOpen:Desc:%s:Len=%d:Scale=%d:T=%d"
		,sColName
		,iLength
		,iScale
		,iColType
		);

        switch (iColType)
        {
	    case SQL_LONGVARBINARY:
	    case SQL_LONGVARCHAR:
		iLength = 65533;
		break;
	    case SQL_DATE:
	    case SQL_TIMESTAMP:
	    case SQL_DECIMAL:
	    case SQL_DOUBLE:
	    case SQL_INTEGER:
	    case SQL_REAL:
	    case SQL_SMALLINT:
		iLength=44;
		break;
	    case SQL_CHAR:
	    case SQL_VARCHAR:
		/* iLength set by Describe
		 */
		break;
	    default:
		iLength = 32768; break;
        }

	/*
	/* Build a "DB" Symbol
	 */
	pDbInfo = NewDbInfo();
	if(!pDbInfo){
	    MsgPush("malloc failed");
	    return(eFalse);
	}
	pDbInfo->pValue  =(char*)malloc(iLength+1);
	pDbInfo->iLen    =iLength+1;
	pDbInfo->iScale  =iScale;
	pDbInfo->iColType=iColType;
	if(!pDbInfo->pValue) {
	    /* Impossible occured! */
	    MsgPush("malloc failed");
	    return(eFalse);
	}
	memset(pDbInfo->pValue,0,iLength+1);
	ENQ(pCursor->lSelect,pDbInfo);	/* For NULL Processing */

	if(ISeTrue(GetSymbolValueREF((char*)sColName,&pBuf))
		&& strlen(pBuf)<=iLength)
	{
	    strcpy(pDbInfo->pValue,pBuf);
		/* Don't assume a symbol was malloc'd, (you hosehead)
		/* Add Symbol will take care of memory leakage...
		 */
	}

	if(! *pDbInfo->pValue)
	     pDbInfo->rlen = SQL_NULL_DATA;
	else pDbInfo->rlen = SQL_NTS;

	RETeFalse2(AddSymbol(SEL_SYMBOL
			    ,DupBuf((const char*)sColName)
			    ,pDbInfo->pValue
			    ,eTrue
			    ,(long)iLength+1
			    )
		  ,"AddSymbol(SEL,%s) Failed." 
		  ,(char*)sColName
		  );

	DebugHTML(__FILE__,__LINE__,2,"DbOpen:AddS(%s)",sColName);

	/* Let Informix Convert everything to STRING
	 */
	rc=SQLBindCol( gaCDA[pCursor->iCursorIndex]
			,Col
			,SQL_C_CHAR
			,&pDbInfo->pValue[0]
			,iLength+1
			,&pDbInfo->rlen
			);
	if(rc!=SQL_SUCCESS && rc!=SQL_SUCCESS_WITH_INFO) {
	    PushDBErr(gaLDA[pCursor->pLDA->iLdaIndex]
		     ,gaCDA[pCursor->iCursorIndex]
		     ,"SQLBindCol failed."
		     );
            return(eFalse);
        }
    }
    return(eTrue);
}

static DbInfo_t *
NewDbInfo()
{
    DbInfo_t *pDbInfo;
    if(!glDbInfoList){
	glDbInfoList=l_create("STACK");
	if(!glDbInfoList) {
	    MsgPush("NewDbInfo:l_create failed");
	    return(0);
	}
    }
    if(l_size(glDbInfoList)>0) {
	DebugHTML(__FILE__,__LINE__,3,"NewDbInfo:POP(%d)",l_size(glDbInfoList));
	pDbInfo=(DbInfo_t*)POP(glDbInfoList);
    } else {
	pDbInfo=(DbInfo_t*)malloc(sizeof(DbInfo_t));
    }
    if(!pDbInfo) {
	MsgPush("NewDbInfo:malloc or POP failed");
	return(0);
    }
    (void)memset(pDbInfo,0,sizeof(DbInfo_t));
    pDbInfo->rlen = SQL_NTS;
    return(pDbInfo);
}

static eBoolean_t
FreeDbInfo(DbInfo_t *pDbInfo)
{
    DebugHTML(__FILE__,__LINE__,3,"FreeDbInfo[%x]",pDbInfo);
    if(!glDbInfoList) {
	glDbInfoList=l_create("STACK");
	if(!glDbInfoList) {
	    MsgPush("FreeDbInfo:l_create failed");
	    return(eFalse);
	}
    }

    /*
    /* Free pValue....
    Free(pDbInfo->pValue);
     */

    /*
    /* Store This PI on the FreeLIst
     */
    DebugHTML(__FILE__,__LINE__,3,"FreeDbInfo:PUSH(%d)",l_size(glDbInfoList));
    PUSH(glDbInfoList,pDbInfo);

    return(eTrue);
}

/*
/* New function for Informix prot.  change the 
/* symbol references in the sql string to 
/* informix's '?' parameters so something like:
/* select * from dual where a = :a
/* becomes
/* select * from dual where a = ?
/* each symbol is converted into a ? parameter and the
/* DbInfo is stuffed onto the lBind list for the
/* cursor.
 */
static eBoolean_t
PrepareParameters(SQLWEB_CURSOR *pCursor)
{
    char *pNewStmt, *cpNew;
    int i, n;
    eBoolean_t bLiteral;
    char *cp;

    /* New stmt will always be at at most the same size
    /* as the origional because any symbol reference is
    /* requires a ':' and a symbol name and the parameter
    /* is a single '?'
     */
    cpNew = pNewStmt = malloc(strlen(pCursor->pStmt)+1);
    if(!pNewStmt) {
	MsgPush("Malloc Failed in PrepareParameters");
        return(eFalse);
    }
    /* Find and bind input variables for placeholders.
     */
    for (i=0, bLiteral=eFalse, cp=pCursor->pStmt; *cp; ) {
	DbInfo_t *pDbInfo;

	/* Single Quoted Strings are SQL literals */
        if (*cp == '\'') {
            bLiteral = ISeTrue(bLiteral)?eFalse:eTrue; /* Toggle */
	}

	/* Oh, boy, we've got a live one!
	 */
        /* if(*cp == ':' && ISeFalse(bLiteral) && *(cp+1) != '=') */
        if(*cp == ':' && ISeFalse(bLiteral))
        {
	    char buf[MAX_SQL_IDENTIFIER];
            for ( ++cp, n=0;
                 *cp && (isalnum(*cp) || *cp == '_')
                     && n < MAX_SQL_IDENTIFIER;
                 cp++, n++
                )
	    {
                buf[n]=*cp;
	    }
            buf[n]=0;		/* NULL the 'buf' Buffer */
	    /* if(! *cp) --cp;	/* If this the end of the buffer, there
				/* is a problem because the outer loop */
				/* increments the cp pointer again, 
				/* BEYOND THE END OF THIS STRING!!!
				 */
	    /*
	    /* buf now points to the SYMBOL NAME
	    /* so...  go-n-get it!
	     */
	    pDbInfo = NewDbInfo();
	    if(!pDbInfo){
		MsgPush("malloc failed");
		return(eFalse);
	    }
	    ENQ(pCursor->lBind,pDbInfo);

	    if(ISeFalse(GetSymbolValueREF(buf,&pDbInfo->pValue))){
		/* There is no symbol by that name, stick in NULL
		/* WARNING?
		 */
		pDbInfo->pValue=0; /* should have been done by Get.. */
		/* pDbInfo->rlen = SQL_NULL_DATA;
		 */
	    }
	    DebugHTML(__FILE__,__LINE__,2
		    ,"DbOpen:GetS(%s:%s)"
		    ,buf
		    ,pDbInfo->pValue? pDbInfo->pValue: ""
		    );

	    pDbInfo->iLen = pDbInfo->pValue ? strlen(pDbInfo->pValue) : 0;
	    /* pDbInfo->ind  = pDbInfo->iLen>0 ? 0 : -1;
	     */

            i++;

	    /* Install the Informix place holder
	     */
	    *cpNew++ = '?';
	    /* *cpNew++ = ' ';
	     */

        }   /* end if (*cp == ':') */
	else {
	    /* Update the Modified SQLStmt
	     */
	    *cpNew++ = *cp++;
	}
    }       /* end for () */
    /* NULL terminate the newly processed SQL stmt
     */
    *cpNew=0;

    /* Update the pCursor Structure 
     */
    pCursor->pStmt = pNewStmt;
    DebugHTML(__FILE__,__LINE__,3,"DbSQL(%s) OK!",pNewStmt);
    return(eTrue);
}

#define ErrMsgLen 200
static void
PushDBErr(HENV pLDA
	 ,HSTMT pCDA
	 ,char *pErrMsg
	 )
{
    RETCODE     rc = SQL_NO_DATA_FOUND;
    SWORD       pcbErrorMsgLen = 0;
    SDWORD      pfNativeError;
    UCHAR	ErrMsg[ErrMsgLen];
    char        SqlState[6];
    HENV        henv = (HENV)0;
    HDBC        hdbc = (HDBC)0;
    HSTMT       hstmt = pCDA;

    if(pErrMsg)
	MsgPush("%s",pErrMsg);

    if(hstmt) {
	rc=SQLError(NULL,NULL,hstmt
		,(UCHAR *)SqlState
		,&pfNativeError
		,(UCHAR *)ErrMsg
		,ErrMsgLen
		,&pcbErrorMsgLen
		);
    } else if(hdbc) {
	rc=SQLError(NULL,hdbc,NULL
		,(UCHAR *)SqlState
		,&pfNativeError
		,(UCHAR *)ErrMsg
		,ErrMsgLen
		,&pcbErrorMsgLen
		);
    } else if (henv) {
	rc=SQLError(henv,NULL,NULL
		,(UCHAR *)SqlState
		,&pfNativeError
		,(UCHAR *)ErrMsg
		,ErrMsgLen
		,&pcbErrorMsgLen
		);
    }

    if(rc==SQL_SUCCESS || rc==SQL_SUCCESS_WITH_INFO) {
	MsgPush("DBERROR:IFMX:%d:%s:%s",pfNativeError,SqlState,ErrMsg);
    } else if (rc== SQL_NO_DATA_FOUND ) {
	MsgPush("DBERROR:IFMX:?:?:Unknown error");
    } else {
	MsgPush("DBERROR:IFMX:?:?:Unknown error rc=%d",rc);
    }
    return;
}

static eBoolean_t
FreeStmt(SQLWEB_CURSOR *pCursor)
{
    RETCODE rc;

    rc=SQLFreeStmt( gaCDA[pCursor->iCursorIndex], SQL_CLOSE );
    if( rc != SQL_SUCCESS && rc != SQL_SUCCESS_WITH_INFO ) {
	PushDBErr(gaLDA[pCursor->pLDA->iLdaIndex]
		 ,gaCDA[pCursor->iCursorIndex]
		 ,"oclose failed."
		 );
	return(eFalse);
    }
    gbaOpen[pCursor->iCursorIndex]=eFalse;
    return(eTrue);
}