After successfully implementing a scan with getattrlistbulk (thanks to https://developer.apple.com/forums/thread/656787/), I'm now trying for each file to get whether the extension is shown in the Finder or not. I think this could be read from the Finder Info (i.e.ATTR_CMN_FNDRINFO), although I'm not sure, since there doesn't seem do be any documentation about what this attribute actually contains. From the setattrlist documentation archive it seems that it is char[32], and I've tried different changes within readUnaligned() so that it would work with an array, but I couldn't get it to work.
Below is my current implementation. The comment How to get Finder Info? shows where the implementation currently doesn't work.
class AppDelegate: NSObject, NSApplicationDelegate {
private static var attributeKeys: attrlist = {
var attributeKeys = attrlist()
attributeKeys.bitmapcount = u_short(ATTR_BIT_MAP_COUNT)
attributeKeys.commonattr = attrgroup_t(ATTR_CMN_RETURNED_ATTRS) | attrgroup_t(bitPattern: ATTR_CMN_ERROR | ATTR_CMN_NAME | ATTR_CMN_OBJTYPE | ATTR_CMN_MODTIME | ATTR_CMN_FNDRINFO | ATTR_CMN_FILEID)
attributeKeys.fileattr = attrgroup_t(bitPattern: ATTR_FILE_DATALENGTH)
return attributeKeys
}()
private let bufferWithAlignment16 = UnsafeMutableRawBufferPointer.allocate(byteCount: 256, alignment: 16)
func applicationDidFinishLaunching(_ notification: Notification) {
let openPanel = NSOpenPanel()
openPanel.canChooseDirectories = true
openPanel.canChooseFiles = false
openPanel.runModal()
try! scan(directoryPath: openPanel.urls[0].path)
}
deinit {
bufferWithAlignment16.deallocate()
}
func scan(directoryPath: String) throws {
let fileDescriptor = open(directoryPath, O_RDONLY)
if fileDescriptor < 0 {
throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno))
}
defer {
let result = close(fileDescriptor)
assert(result == 0)
}
let attributeBuffer = UnsafeMutableRawBufferPointer.allocate(byteCount: 2048, alignment: 16)
defer {
attributeBuffer.deallocate()
}
while true {
let itemCount = Int(getattrlistbulk(fileDescriptor, &AppDelegate.attributeKeys, attributeBuffer.baseAddress!, attributeBuffer.count, 0))
if itemCount == 0 {
return
} else if itemCount > 0 {
var entryOffset = attributeBuffer.baseAddress!
for _ in 0..<itemCount {
let length = Int(entryOffset.load(as: UInt32.self))
try unpackResources(at: entryOffset + MemoryLayout<UInt32>.size, parentDirectory: directoryPath)
entryOffset += length
}
} else if errno != EINTR {
throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno))
}
}
}
private func unpackResources(at attributeOffset: UnsafeMutableRawPointer, parentDirectory: String) throws {
var attributeOffset = attributeOffset
let returned = attributeOffset.load(as: attribute_set_t.self)
attributeOffset += MemoryLayout<attribute_set_t>.size
var error: Error?
if (returned.commonattr & attrgroup_t(bitPattern: ATTR_CMN_ERROR)) != 0 {
error = NSError(domain: NSPOSIXErrorDomain, code: Int(attributeOffset.load(as: UInt32.self)))
attributeOffset += MemoryLayout<UInt32>.size
}
let name: String
if (returned.commonattr & attrgroup_t(bitPattern: ATTR_CMN_NAME)) != 0 {
let nameInfo = attributeOffset.load(as: attrreference_t.self)
name = String(cString: (attributeOffset + Int(nameInfo.attr_dataoffset)).assumingMemoryBound(to: CChar.self))
attributeOffset += MemoryLayout<attrreference_t>.size
} else {
name = ""
}
let fileType: fsobj_type_t
if (returned.commonattr & attrgroup_t(bitPattern: ATTR_CMN_OBJTYPE)) != 0 {
fileType = attributeOffset.load(as: fsobj_type_t.self)
attributeOffset += MemoryLayout<fsobj_type_t>.size
} else {
fileType = VNON.rawValue
}
var modificationDate: Date?
if (returned.commonattr & attrgroup_t(bitPattern: ATTR_CMN_MODTIME)) != 0 {
modificationDate = Date(timeIntervalSince1970: TimeInterval(readUnaligned(pointer: attributeOffset, as: timespec.self).tv_sec))
attributeOffset += MemoryLayout<timespec>.size
}
// How to get Finder Info?
let finderInfo: [Int8]
if (returned.commonattr & attrgroup_t(bitPattern: ATTR_CMN_FNDRINFO)) != 0 {
finderInfo = readUnaligned(pointer: attributeOffset, as: [Int8].self)
attributeOffset += MemoryLayout<Int8>.size
} else {
finderInfo = []
}
let fileId: UInt64
if (returned.commonattr & attrgroup_t(bitPattern: ATTR_CMN_FILEID)) != 0 {
fileId = readUnaligned(pointer: attributeOffset, as: UInt64.self)
attributeOffset += MemoryLayout<UInt64>.size
} else {
fileId = 0
}
let size: Int64
if (returned.fileattr & attrgroup_t(bitPattern: ATTR_FILE_DATALENGTH)) != 0 {
size = Int64(readUnaligned(pointer: attributeOffset, as: off_t.self))
attributeOffset += MemoryLayout<off_t>.size
} else {
size = 0
}
if let error = error {
throw error
}
let isDirectory = fileType == VDIR.rawValue
let isSymbolicLink = fileType == VLNK.rawValue
print(name, isDirectory, isSymbolicLink, modificationDate as Any, finderInfo, fileId, size)
}
private func readUnaligned<Result>(pointer: UnsafeRawPointer, as: Result.Type) -> Result {
bufferWithAlignment16.copyMemory(from: UnsafeRawBufferPointer(start: pointer, count: MemoryLayout<Result>.size))
return bufferWithAlignment16.baseAddress!.load(as: Result.self)
}
}
