Persisting bookmark in core-data - objective-c

Question

I have an OSX application that is supposed to have a list of files from anywhere in the user's disk.
The first version of the app saves the path to these files in a core-data model.
However, if the file is moved or renamed, the tool loses its purpose and the app can crash.
So I decided to use bookmarks. It seems to be working, but every time I try to recover the data, I get the old path of the files. Why is that? What am I missing?
My core-data entity uses a binary data field to persist the bookmark.
The bookmark itself is done like this:
NSData * bookmark = [filePath bookmarkDataWithOptions:NSURLBookmarkCreationMinimalBookmark
includingResourceValuesForKeys:NULL
relativeToURL:NULL
error:NULL];
And on loading the application, I have a loop to iterate all the table and recover the bookmark like this:
while (object = [rowEnumerator nextObject]) {
NSError * error = noErr;
NSURL * bookmark = [NSURL URLByResolvingBookmarkData:[object fileBookmark]
options:NSURLBookmarkResolutionWithoutUI
relativeToURL:NULL
bookmarkDataIsStale:NO
error:&error];
if (error != noErr)
DDLogCError(#"%#", [error description]);
DDLogCInfo(#"File Path: %#", [bookmark fileReferenceURL]);
}
If I rename the file, the path is null. I see no difference between storing this NSData object and a string with the path. So I am obviously missing something.
Edit:
I also often get an error like this: CFURLSetTemporaryResourcePropertyForKey failed because it was passed this URL which has no scheme.
I appreciate any help, thanks!

Answer 1

I can't find any issues in my code, so I changed it.
After looking for the reason of the "no scheme" message, I came to the conclusion some third-party application is required for this code to work, and that's undesirable.
I am now using aliases. This is how I create them:
FSRef fsFile, fsOriginal;
AliasHandle aliasHandle;
NSString * fileOriginalPath = [[filePath absoluteString] stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
OSStatus status = FSPathMakeRef((unsigned char*)[fileOriginalPath cStringUsingEncoding: NSUTF8StringEncoding], &fsOriginal, NULL);
status = FSPathMakeRef((unsigned char*)[fileOriginalPath cStringUsingEncoding: NSUTF8StringEncoding], &fsFile, NULL);
OSErr err = FSNewAlias(&fsOriginal, &fsFile, &aliasHandle);
NSData * aliasData = [NSData dataWithBytes: *aliasHandle length: GetAliasSize(aliasHandle)];
And now I recover the path like this:
while (object = [rowEnumerator nextObject]) {
NSData * aliasData = [object fileBookmark];
NSUInteger aliasLen = [aliasData length];
if (aliasLen > 0) {
FSRef fsFile, fsOriginal;
AliasHandle aliasHandle;
OSErr err = PtrToHand([aliasData bytes], (Handle*)&aliasHandle, aliasLen);
Boolean changed;
err = FSResolveAlias(&fsOriginal, aliasHandle, &fsFile, &changed);
if (err == noErr) {
char pathC[2*1024];
OSStatus status = FSRefMakePath(&fsFile, (UInt8*) &pathC, sizeof(pathC));
NSAssert(status == 0, #"FSRefMakePath failed");
NSLog(#"%#", [NSString stringWithCString: pathC encoding: NSUTF8StringEncoding]);
} else {
NSLog(#"The file disappeared!");
}
} else {
NSLog(#"CardCollectionUserDefault was zero length");
}
}
However, I am still curious on why my previous code failed. I appreciate any thoughts on that. Thanks!