FreeTDS Development Group

["Xander Maas (GMAIL)" <xjmaas AT gmail.com>]

Hi all,

I am just beginning using the FreeTDS library to write an Objective-C 
application for Mac OS X. I have build the library from the 
freetds-0.82.1.dev.20100810 tree.

When I try to get a second column containing a SYBINT4 column, I keep getting 
a EXC_BAD_ACCESS error from gdb. I have tried several ways to get the value, 
to no avail.

I am trying this in the code below. First I tried it with dbdata, like 
intObject=*((DBINT *)dbdata(sybConn,i)); but also using a memcpy.

The first time I fetch the SYBINT4 I get the correct result, the second 
column I fetch, kills my application.

Hope someone can help me with this.

Thanks in advance,

Xander


- (NSArray *)getRecordForCurrentRow {
        int numCols = [self numberOfFields];
        int i;
        NSMutableArray *record = [NSMutableArray arrayWithCapacity:numCols];
        
        /* First run through the columns and get their type and put their 
value
         * in our Array
         */
        
        static DBINT intObject;
        char charObject[255];
        char varCharObject[255];
        /*
         * To be implemented later on...
         * float floatObject;
         */

        NSLog(@"We have %d columns to process", numCols);
        
        for ( i = 1; i < (numCols + 1); i++ ) {
                NSLog(@"We got a field of type: %d for column %d", 
dbcoltype(sybConn, i), i);
                switch (dbcoltype(sybConn, i)) {
                        case SYBINT4:

                                NSLog(@"We want to read the value at: %d", 
(DBINT *)dbdata(sybConn, 1));
                                
                                /* 
                                 * We want to return a value, if we got no 
value from the query, BUT
                                 * requested the field, return a nil to be 
inserted into the array
                                 */
                                /*
                                if (dbdatlen(sybConn, i) == 0 ) {
                                        NSLog(@"The length of this intObject 
is: %d", dbdatlen(sybConn, i));
                                        NSLog(@"We got no result? adding nil 
to array");
                                        [record addObject:[NSNumber 
numberWithInt:0]];
                                } else {
                                        NSLog(@"The length of this intObject 
is: %d", dbdatlen(sybConn, i));

                                        intObject = *((DBINT 
*)dbdata(sybConn, i));
                                        
                                        // Add the INT value to the array
                                        NSLog(@"Adding INT: %d", intObject);
                                        [record addObject:[NSNumber 
numberWithInt:intObject]];
                                }
                                 */
                                
                                memcpy(&intObject, dbdata(sybConn, i), 
sizeof(intObject));
                                NSLog(@"Add the INT value: %d", intObject);
                                [record addObject:[NSNumber 
numberWithInt:intObject]];
                                
                                break;
                        case SYBCHAR:                           

                                if (dbdatlen(sybConn, 1) == 0 ) {
                                        NSLog(@"The length of this charObject 
is: %d", dbdatlen(sybConn, i));
                                        NSLog(@"We got no result? adding nil 
to array");
                                        [record addObject:[NSString 
stringWithString:@""]];
                                } else {
                                         /* Copy the data from the buffer */
                                        NSLog(@"This wil be address of our 
charObject: %d", &charObject);
                                        strncpy(charObject, (char 
*)dbdata(sybConn, i), (int)dbdatlen(sybConn, i));
                                
                                        /* Add the terminating null character 
*/
                                        charObject[dbdatlen(sybConn, i)] = 
'\0';
                                
                                        /* Add the charObject to the Array */
                                        [record addObject: [self 
stringWithUTF8CString:charObject] ];
                                        NSLog(@"Adding NSString value %s", 
charObject);
                                }
                                break;
                        case SYBVARCHAR:
                                if (dbdatlen(sybConn, 1) == 0 ) {
                                        NSLog(@"The length of this charObject 
is: %d", dbdatlen(sybConn, i));
                                        NSLog(@"We got no result? adding nil 
to array");
                                        [record addObject:[NSString 
stringWithString:@""]];
                                } else {
                                        
                                        /* Copy the data from the buffer */
                                        strncpy(varCharObject, (char 
*)dbdata(sybConn, i), (int)dbdatlen(sybConn, i));
                                 
                                        /* Add the terminating null character 
*/
                                        charObject[dbdatlen(sybConn, i)] = 
'\0';
                                  
                                        /* Add the charObject to the Array */
                                        [record addObject:[self 
stringWithUTF8CString:varCharObject]];
                                        NSLog(@"Adding NSString value %s", 
varCharObject);
                                }
                                break;

                        default:
                                return NULL;
                                break;
                }
        }
        NSLog(@"We got the following Array: \n%@", record);
        return (record) ? [NSArray arrayWithArray:record] : nil;
}