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Merged
merged 1 commit into from
Jul 22, 2019
Merged

Implement _contentsEqual on Windows #2411

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28 changes: 0 additions & 28 deletions Foundation/FileManager+POSIX.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -853,34 +853,6 @@ extension FileManager {
}
}

private func _compareFiles(withFileSystemRepresentation file1Rep: UnsafePointer<Int8>, andFileSystemRepresentation file2Rep: UnsafePointer<Int8>, size: Int64, bufSize: Int) -> Bool {
guard let file1 = FileHandle(fileSystemRepresentation: file1Rep, flags: O_RDONLY, createMode: 0) else { return false }
guard let file2 = FileHandle(fileSystemRepresentation: file2Rep, flags: O_RDONLY, createMode: 0) else { return false }

var buffer1 = UnsafeMutablePointer<UInt8>.allocate(capacity: bufSize)
var buffer2 = UnsafeMutablePointer<UInt8>.allocate(capacity: bufSize)
defer {
buffer1.deallocate()
buffer2.deallocate()
}
var bytesLeft = size
while bytesLeft > 0 {
let bytesToRead = Int(min(Int64(bufSize), bytesLeft))

guard let file1BytesRead = try? file1._readBytes(into: buffer1, length: bytesToRead), file1BytesRead == bytesToRead else {
return false
}
guard let file2BytesRead = try? file2._readBytes(into: buffer2, length: bytesToRead), file2BytesRead == bytesToRead else {
return false
}
guard memcmp(buffer1, buffer2, bytesToRead) == 0 else {
return false
}
bytesLeft -= Int64(bytesToRead)
}
return true
}

private func _compareSymlinks(withFileSystemRepresentation file1Rep: UnsafePointer<Int8>, andFileSystemRepresentation file2Rep: UnsafePointer<Int8>, size: Int64) -> Bool {
let bufSize = Int(size)
let buffer1 = UnsafeMutablePointer<CChar>.allocate(capacity: bufSize)
Expand Down
102 changes: 89 additions & 13 deletions Foundation/FileManager+Win32.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -589,7 +589,7 @@ extension FileManager {

if ffd.dwFileAttributes & DWORD(FILE_ATTRIBUTE_READONLY) == FILE_ATTRIBUTE_READONLY {
let readableAttributes = ffd.dwFileAttributes & DWORD(bitPattern: ~FILE_ATTRIBUTE_READONLY)
guard file.withCString(encodedAs: UTF16.self, { SetFileAttributesW($0, readableAttributes) }) else {
guard itemPath.withCString(encodedAs: UTF16.self, { SetFileAttributesW($0, readableAttributes) }) else {
throw _NSErrorWithWindowsError(GetLastError(), reading: false, paths: [file])
}
}
Expand Down Expand Up @@ -684,10 +684,6 @@ extension FileManager {
return true
}

internal func _compareFiles(withFileSystemRepresentation file1Rep: UnsafePointer<Int8>, andFileSystemRepresentation file2Rep: UnsafePointer<Int8>, size: Int64, bufSize: Int) -> Bool {
NSUnimplemented()
}

internal func _lstatFile(atPath path: String, withFileSystemRepresentation fsRep: UnsafePointer<Int8>? = nil) throws -> stat {
let _fsRep: UnsafePointer<Int8>
if fsRep == nil {
Expand Down Expand Up @@ -749,7 +745,86 @@ extension FileManager {
}

internal func _contentsEqual(atPath path1: String, andPath path2: String) -> Bool {
NSUnimplemented()
guard let path1Handle = path1.withCString(encodedAs: UTF16.self, {
CreateFileW($0, GENERIC_READ, DWORD(FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE), nil,
DWORD(OPEN_EXISTING), DWORD(FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_BACKUP_SEMANTICS), nil)
}), path1Handle != INVALID_HANDLE_VALUE else {
return false
}

defer { CloseHandle(path1Handle) }

guard let path2Handle = path2.withCString(encodedAs: UTF16.self, {
CreateFileW($0, GENERIC_READ, DWORD(FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE), nil,
DWORD(OPEN_EXISTING), DWORD(FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_BACKUP_SEMANTICS), nil)
}), path2Handle != INVALID_HANDLE_VALUE else {
return false
}
defer { CloseHandle(path2Handle) }

let file1Type = GetFileType(path1Handle)
guard GetLastError() == NO_ERROR else {
return false
}
let file2Type = GetFileType(path2Handle)
guard GetLastError() == NO_ERROR else {
return false
}

guard file1Type == FILE_TYPE_DISK, file2Type == FILE_TYPE_DISK else {
return false
}

var path1FileInfo = BY_HANDLE_FILE_INFORMATION()
var path2FileInfo = BY_HANDLE_FILE_INFORMATION()
guard GetFileInformationByHandle(path1Handle, &path1FileInfo),
GetFileInformationByHandle(path2Handle, &path2FileInfo) else {
return false
}

// If both paths point to the same volume/filenumber or they are both zero length
// then they are considered equal
if path1FileInfo.nFileIndexHigh == path2FileInfo.nFileIndexHigh
&& path1FileInfo.nFileIndexLow == path2FileInfo.nFileIndexLow
&& path1FileInfo.dwVolumeSerialNumber == path2FileInfo.dwVolumeSerialNumber {
return true
}

let path1Attrs = path1FileInfo.dwFileAttributes
let path2Attrs = path2FileInfo.dwFileAttributes
if path1Attrs & DWORD(FILE_ATTRIBUTE_REPARSE_POINT) == FILE_ATTRIBUTE_REPARSE_POINT
|| path2Attrs & DWORD(FILE_ATTRIBUTE_REPARSE_POINT) == FILE_ATTRIBUTE_REPARSE_POINT {
guard path1Attrs & DWORD(FILE_ATTRIBUTE_REPARSE_POINT) == FILE_ATTRIBUTE_REPARSE_POINT
&& path2Attrs & DWORD(FILE_ATTRIBUTE_REPARSE_POINT) == FILE_ATTRIBUTE_REPARSE_POINT else {
return false
}
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Huh? What am I missing? Isn't this the condition that is in the if?

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The inner one is &&, the outer is ||. If either is a reparse point, go into the if, but if one is not a reparse point, the immediately bail out. Sadly there's no logical XOR which might make that clearer.

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Hmm, does ^ not work here?

guard let pathDest1 = try? _destinationOfSymbolicLink(atPath: path1),
let pathDest2 = try? _destinationOfSymbolicLink(atPath: path2) else {
return false
}
return pathDest1 == pathDest2
} else if DWORD(FILE_ATTRIBUTE_DIRECTORY) & path1Attrs == DWORD(FILE_ATTRIBUTE_DIRECTORY)
|| DWORD(FILE_ATTRIBUTE_DIRECTORY) & path2Attrs == DWORD(FILE_ATTRIBUTE_DIRECTORY) {
guard DWORD(FILE_ATTRIBUTE_DIRECTORY) & path1Attrs == DWORD(FILE_ATTRIBUTE_DIRECTORY)
&& DWORD(FILE_ATTRIBUTE_DIRECTORY) & path2Attrs == FILE_ATTRIBUTE_DIRECTORY else {
return false
}
return _compareDirectories(atPath: path1, andPath: path2)
} else {
if path1FileInfo.nFileSizeHigh == 0 && path1FileInfo.nFileSizeLow == 0
&& path2FileInfo.nFileSizeHigh == 0 && path2FileInfo.nFileSizeLow == 0 {
return true
}

let path1Fsr = fileSystemRepresentation(withPath: path1)
defer { path1Fsr.deallocate() }
let path2Fsr = fileSystemRepresentation(withPath: path2)
defer { path2Fsr.deallocate() }
return _compareFiles(withFileSystemRepresentation: path1Fsr,
andFileSystemRepresentation: path2Fsr,
size: (Int64(path1FileInfo.nFileSizeHigh) << 32) | Int64(path1FileInfo.nFileSizeLow),
bufSize: 0x1000)
}
}

internal func _appendSymlinkDestination(_ dest: String, toPath: String) -> String {
Expand Down Expand Up @@ -810,7 +885,7 @@ extension FileManager {
override func nextObject() -> Any? {
func firstValidItem() -> URL? {
while let url = _stack.popLast() {
if !FileManager.default.fileExists(atPath: url.path, isDirectory: nil) {
if !FileManager.default.fileExists(atPath: url.path) {
guard let handler = _errorHandler,
handler(url, _NSErrorWithWindowsError(GetLastError(), reading: true, paths: [url.path]))
else { return nil }
Expand All @@ -823,15 +898,16 @@ extension FileManager {
}

// If we most recently returned a directory, decend into it
var isDir: ObjCBool = false
guard FileManager.default.fileExists(atPath: _lastReturned.path, isDirectory: &isDir) else {
guard let handler = _errorHandler,
guard let attrs = try? FileManager.default.windowsFileAttributes(atPath: _lastReturned.path) else {
guard let handler = _errorHandler,
handler(_lastReturned, _NSErrorWithWindowsError(GetLastError(), reading: true, paths: [_lastReturned.path]))
else { return nil }
return firstValidItem()
else { return nil }
return firstValidItem()
}

if isDir.boolValue && (level == 0 || !_options.contains(.skipsSubdirectoryDescendants)) {
let isDir = attrs.dwFileAttributes & DWORD(FILE_ATTRIBUTE_DIRECTORY) == DWORD(FILE_ATTRIBUTE_DIRECTORY)
&& attrs.dwFileAttributes & DWORD(FILE_ATTRIBUTE_REPARSE_POINT) == 0
if isDir && (level == 0 || !_options.contains(.skipsSubdirectoryDescendants)) {
var ffd = WIN32_FIND_DATAW()
let dirPath = joinPath(prefix: _lastReturned.path, suffix: "*")
let handle = dirPath.withCString(encodedAs: UTF16.self) {
Expand Down
31 changes: 30 additions & 1 deletion Foundation/FileManager.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -825,6 +825,8 @@ open class FileManager : NSObject {
guard let enumerator2 = enumerator(atPath: path2) else {
return false
}
enumerator1.skipDescendants()
enumerator2.skipDescendants()

var path1entries = Set<String>()
while let item = enumerator1.nextObject() as? String {
Expand Down Expand Up @@ -871,9 +873,36 @@ open class FileManager : NSObject {
}()
#endif

internal func _compareFiles(withFileSystemRepresentation file1Rep: UnsafePointer<Int8>, andFileSystemRepresentation file2Rep: UnsafePointer<Int8>, size: Int64, bufSize: Int) -> Bool {
guard let file1 = FileHandle(fileSystemRepresentation: file1Rep, flags: O_RDONLY, createMode: 0) else { return false }
guard let file2 = FileHandle(fileSystemRepresentation: file2Rep, flags: O_RDONLY, createMode: 0) else { return false }

var buffer1 = UnsafeMutablePointer<UInt8>.allocate(capacity: bufSize)
var buffer2 = UnsafeMutablePointer<UInt8>.allocate(capacity: bufSize)
defer {
buffer1.deallocate()
buffer2.deallocate()
}
var bytesLeft = size
while bytesLeft > 0 {
let bytesToRead = Int(min(Int64(bufSize), bytesLeft))

guard let file1BytesRead = try? file1._readBytes(into: buffer1, length: bytesToRead), file1BytesRead == bytesToRead else {
return false
}
guard let file2BytesRead = try? file2._readBytes(into: buffer2, length: bytesToRead), file2BytesRead == bytesToRead else {
return false
}
guard memcmp(buffer1, buffer2, bytesToRead) == 0 else {
return false
}
bytesLeft -= Int64(bytesToRead)
}
return true
}

/* -contentsEqualAtPath:andPath: does not take into account data stored in the resource fork or filesystem extended attributes.
*/
@available(Windows, deprecated, message: "Not Yet Implemented")
open func contentsEqual(atPath path1: String, andPath path2: String) -> Bool {
return _contentsEqual(atPath: path1, andPath: path2)
}
Expand Down
32 changes: 32 additions & 0 deletions TestFoundation/TestFileManager.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -841,6 +841,9 @@ class TestFileManager : XCTestCase {
let srcLink = srcPath + "/testlink"
let destLink = destPath + "/testlink"
do {
#if os(Windows)
fm.createFile(atPath: srcPath.appendingPathComponent("linkdest"), contents: Data(), attributes: nil)
#endif
try fm.createSymbolicLink(atPath: srcLink, withDestinationPath: "linkdest")
try fm.copyItem(atPath: srcLink, toPath: destLink)
XCTAssertEqual(try fm.destinationOfSymbolicLink(atPath: destLink), "linkdest")
Expand Down Expand Up @@ -925,6 +928,9 @@ class TestFileManager : XCTestCase {
let srcLink = srcPath + "/testlink"
let destLink = destPath + "/testlink"
do {
#if os(Windows)
fm.createFile(atPath: srcPath.appendingPathComponent("linkdest"), contents: Data(), attributes: nil)
#endif
try fm.createSymbolicLink(atPath: srcLink, withDestinationPath: "linkdest")
try fm.linkItem(atPath: srcLink, toPath: destLink)
XCTAssertEqual(try fm.destinationOfSymbolicLink(atPath: destLink), "linkdest")
Expand Down Expand Up @@ -1009,8 +1015,10 @@ class TestFileManager : XCTestCase {

// testDir1
try fm.createDirectory(atPath: testDir1.path, withIntermediateDirectories: true)
#if !os(Windows)
try fm.createSymbolicLink(atPath: testDir1.appendingPathComponent("null1").path, withDestinationPath: "/dev/null")
try fm.createSymbolicLink(atPath: testDir1.appendingPathComponent("zero1").path, withDestinationPath: "/dev/zero")
#endif
try "foo".write(toFile: testDir1.appendingPathComponent("foo.txt").path, atomically: false, encoding: .ascii)
try fm.createSymbolicLink(atPath: testDir1.appendingPathComponent("foo1").path, withDestinationPath: "foo.txt")
try fm.createSymbolicLink(atPath: testDir1.appendingPathComponent("bar2").path, withDestinationPath: "foo1")
Expand All @@ -1026,32 +1034,55 @@ class TestFileManager : XCTestCase {

// testDir2
try fm.createDirectory(atPath: testDir2.path, withIntermediateDirectories: true)
#if os(Windows)
try "foo".write(toFile: testDir2.appendingPathComponent("foo1").path, atomically: false, encoding: .ascii)
try fm.createDirectory(atPath: testDir2.appendingPathComponent("../testDir1").path, withIntermediateDirectories: true)
try "foo".write(toFile: testDir2.appendingPathComponent("../testDir1/foo.txt").path, atomically: false, encoding: .ascii)
#endif
try fm.createSymbolicLink(atPath: testDir2.appendingPathComponent("bar2").path, withDestinationPath: "foo1")
try fm.createSymbolicLink(atPath: testDir2.appendingPathComponent("foo2").path, withDestinationPath: "../testDir1/foo.txt")

// testDir3
try fm.createDirectory(atPath: testDir3.path, withIntermediateDirectories: true)
#if os(Windows)
try fm.createDirectory(atPath: testDir3.appendingPathComponent("../testDir1").path, withIntermediateDirectories: true)
try "foo".write(toFile: testDir3.appendingPathComponent("../testDir1/foo.txt").path, atomically: false, encoding: .ascii)
try "foo".write(toFile: testDir3.appendingPathComponent("foo1").path, atomically: false, encoding: .ascii)
#endif
try fm.createSymbolicLink(atPath: testDir3.appendingPathComponent("bar2").path, withDestinationPath: "foo1")
try fm.createSymbolicLink(atPath: testDir3.appendingPathComponent("foo2").path, withDestinationPath: "../testDir1/foo.txt")
} catch {
XCTFail(String(describing: error))
}

#if os(Windows)
XCTAssertFalse(fm.contentsEqual(atPath: "NUL", andPath: "NUL"))
#else
XCTAssertTrue(fm.contentsEqual(atPath: "/dev/null", andPath: "/dev/null"))
XCTAssertTrue(fm.contentsEqual(atPath: "/dev/urandom", andPath: "/dev/urandom"))
XCTAssertFalse(fm.contentsEqual(atPath: "/dev/null", andPath: "/dev/zero"))
XCTAssertFalse(fm.contentsEqual(atPath: testDir1.appendingPathComponent("null1").path, andPath: "/dev/null"))
XCTAssertFalse(fm.contentsEqual(atPath: testDir1.appendingPathComponent("zero").path, andPath: "/dev/zero"))
#endif
XCTAssertFalse(fm.contentsEqual(atPath: testDir1.appendingPathComponent("foo.txt").path, andPath: testDir1.appendingPathComponent("foo1").path))
XCTAssertFalse(fm.contentsEqual(atPath: testDir1.appendingPathComponent("foo.txt").path, andPath: testDir1.appendingPathComponent("foo2").path))
XCTAssertTrue(fm.contentsEqual(atPath: testDir1.appendingPathComponent("bar2").path, andPath: testDir2.appendingPathComponent("bar2").path))
XCTAssertFalse(fm.contentsEqual(atPath: testDir1.appendingPathComponent("foo1").path, andPath: testDir2.appendingPathComponent("foo2").path))
XCTAssertFalse(fm.contentsEqual(atPath: "/non_existent_file", andPath: "/non_existent_file"))

let emptyFile = testDir1.appendingPathComponent("empty_file")
#if os(Windows)
XCTAssertFalse(fm.contentsEqual(atPath: emptyFile.path, andPath: "NUL"))
#else
XCTAssertFalse(fm.contentsEqual(atPath: emptyFile.path, andPath: "/dev/null"))
#endif
XCTAssertFalse(fm.contentsEqual(atPath: emptyFile.path, andPath: testDir1.appendingPathComponent("null1").path))
#if os(Windows)
// A file cannot be unreadable on Windows
XCTAssertTrue(fm.contentsEqual(atPath: emptyFile.path, andPath: testDir1.appendingPathComponent("unreadable_file").path))
#else
XCTAssertFalse(fm.contentsEqual(atPath: emptyFile.path, andPath: testDir1.appendingPathComponent("unreadable_file").path))
#endif

XCTAssertTrue(fm.contentsEqual(atPath: testFile1URL.path, andPath: testFile1URL.path))
XCTAssertFalse(fm.contentsEqual(atPath: testFile1URL.path, andPath: testFile2URL.path))
Expand Down Expand Up @@ -1774,6 +1805,7 @@ VIDEOS=StopgapVideos
("test_getRelationship", test_getRelationship),
("test_displayNames", test_displayNames),
("test_getItemReplacementDirectory", test_getItemReplacementDirectory),
("test_contentsEqual", test_contentsEqual),
/* ⚠️ */ ("test_replacement", testExpectedToFail(test_replacement,
/* ⚠️ */ "<https://bugs.swift.org/browse/SR-10819> Re-enable Foundation test TestFileManager.test_replacement")),
]
Expand Down