SQLPutData() with a size of zero

Hello,

I believe I found a defect (0.92.377): with SQL_DATA_AT_EXEC binding, when a
blob is empty but not null, it should be possible to call SQLPutData() with
a size of zero:

    r = SQLPutData(st->stmtHandle, (SQLPOINTER) "", 0L);

This is working with SQL Native Client and Easysoft ODBC for SQL Server...

But FreeTDS returns:

HY001 / [FreeTDS][SQL Server]Memory allocation failure

...

It appears that the code in prepare_query.c:continue_parse_prepared_query()
is not prepared to get a StrLen_or_Ind of zero...

In fact we end up in this part, with len=0:

                 if (blob->textvalue)
                         p = (TDS_CHAR *) realloc(blob->textvalue, len + curcol->column_cur_size);
                 else {
                         assert(curcol->column_cur_size == 0);
                         p = (TDS_CHAR *) malloc(len);
                 }
                 if (!p) {
                         odbc_errs_add(&stmt->errs, "HY001", NULL); /* Memory allocation error */
                         return SQL_ERROR;
                 }


and here malloc(0) returns zero (AIX 6.1)...

Seb