************************** SDStoreFile.h *******************************



@class SDStoreDirectory;



@interface SDStoreFile:SDStore







{

    BOOL allowWriting;

    NSString *filename;

    NSString *pplFileName;

    NSPPL *ppl;

}



- (id) initWithFile: (NSString *)aFilename;

- (id) initFromFile: (NSString *)aFilename forWriting: (BOOL) writeFlag;

- (void) createBlock:(int *)blockNumber withSize:(unsigned int)aSize;



- (NSString *)filename;



@end





*************************** SDStoreFile.m *******************************



///////////////////////////////////////////////////////////////////////////

//

//      SDStoreFile

//            kaj: Jun 4 1997

//            Purpose: cover for IXStoreFile methods

//      Implemented using an NSPPL (Persistent Property List)

//

///////////////////////////////////////////////////////////////////////////



#import "ixCover.h"



@implementation SDStoreFile:SDStore



#define PPL_FILE_NAME @"Store.ppl"

#define PRIVATE_INFO @"privateInfo"



///////////////////////////////////////////////////////////////////////////

//      

//      initWithFile:

//

//      Initializes the IXStoreFile with filename as its storage file.

//      filename is created and opened for reading and writing,

//      and locked for exclusive access.  This the designated initializer

//      for the IXStoreFile class.  Returns self.

//

///////////////////////////////////////////////////////////////////////////

- (id) initWithFile: (NSString *)aFilename

{

    [super init];



    if (!aFilename) {

        [self release];

        return nil;

    }

    

    filename = [[NSString allocWithZone:[self zone]] initWithString:aFilename];

    

    // check to make sure directory doesn't exist

    if ([[NSFileManager defaultManager] fileExistsAtPath:filename]) {

      // should put up a warning panel that the file exists

      [self release];

      return nil;

    } else {

      // create directory

      [[NSFileManager defaultManager] createDirectoryAtPath:filename attributes: nil];

      

      // create a ppl in directory

      ppl = [[NSPPL allocWithZone:[self zone]] initWithPath:[filename stringByAppendingPathComponent:PPL_FILE_NAME] create:YES readOnly:NO];



        rootDictionary = [[ppl rootDictionary]retain];

        [rootDictionary setObject:privateInfo forKey:PRIVATE_INFO];

        allowWriting = YES;

        transactionLevel = 0;

    }

    

    return self;

}



- (id) initFromFile: (NSString *)aFilename forWriting: (BOOL) writeFlag 

{

    BOOL isDirectory;

    

    [super init];



    if (!aFilename) {

        [self release];

        return nil;

    }

    

    filename = [[NSString allocWithZone:[self zone]] initWithString:aFilename];

    

    // check to make sure directory exists

    if (![[NSFileManager defaultManager] fileExistsAtPath:filename isDirectory:&isDirectory] || !isDirectory) {

      // raise an exception

      [self release];

      return nil;

    }



    NS_DURING

        

       // read the ppl

        pplFileName = [filename stringByAppendingPathComponent:PPL_FILE_NAME];

        

        // NOTE: I was unable to get a root dictionary from a PPL that was opened as readOnly. I don't know why. For right now, we'll just open everything has writeable; later, we may want to investigate further

        // A possible solution is to create a copy PPL and use that; no changes will be reflected back in the original PPL

        

        ppl = [[NSPPL allocWithZone:[self zone]] initWithPath:pplFileName create:NO readOnly:NO];



        if (!ppl) {

            [self release];

            return  nil;

        }



        // read the rootDictionary

        

        rootDictionary = [[ppl rootDictionary] retain];



        

    NS_HANDLER



        // later, we may want to try to recover the PPL from the userInfo dictionary

        [localException raise];



    NS_ENDHANDLER



    [pplFileName retain];

    privateInfo = [[rootDictionary objectForKey:PRIVATE_INFO]retain];

    

    // get the last block number

    lastBlock = [self readLastBlockNumber];

    

    allowWriting = writeFlag;

    transactionLevel = 0;

    return self;

}



- (void) createBlock:(int *)blockNumber withSize:(unsigned int)aSize

{

    *blockNumber = ++lastBlock;

    [self recordLastBlockNumber];

}





- (void) commitTransaction

{

    [super commitTransaction];

    [ppl save];

}



- (void) dealloc

{

    [rootDictionary release];

    [ppl release];



    [pplFileName release];

    [filename release];

    [super dealloc];

}





- (NSString *)filename

{

    return filename;

}



@end