Skip to content

Commit

Permalink
[io] Fix a bug where relative symlinks to directories did not work on…
Browse files Browse the repository at this point in the history 
… Windows.

Also modified `File::GetType` on Windows to correctly report the type of broken links as notFound.

Windows fixes:
co19/LibTest/io/Link/createSync_A04_t08
co19/LibTest/io/Link/createSync_A04_t10
co19/LibTest/io/Link/createSync_A04_t12
co19/LibTest/io/Link/createSync_A04_t14
co19/LibTest/io/Link/createSync_A04_t16
co19/LibTest/io/Link/createSync_A06_t01
co19/LibTest/io/Link/createSync_A06_t03
co19/LibTest/io/Link/createSync_A06_t06
co19/LibTest/io/Link/createSync_A06_t08
co19/LibTest/io/Link/create_A04_t08
co19/LibTest/io/Link/create_A04_t10
co19/LibTest/io/Link/create_A04_t12
co19/LibTest/io/Link/create_A04_t14
co19/LibTest/io/Link/create_A04_t16
co19/LibTest/io/Link/create_A06_t01
co19/LibTest/io/Link/create_A06_t03
co19/LibTest/io/Link/create_A06_t06
co19/LibTest/io/Link/create_A06_t08
co19/LibTest/io/Link/resolveSymbolicLinksSync_A01_t01
co19/LibTest/io/Link/resolveSymbolicLinks_A01_t01


Bug:#53848
Bug:#45981
Change-Id: I3d156f38540089d8adb12dbb79d0477330d9eb07
Tested: updated unit tests plus fixes existing tests
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/335940
Commit-Queue: Brian Quinlan <bquinlan@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
  • Loading branch information
@brianquinlan
brianquinlan authored and Commit Queue committed Feb 21, 2024
1 parent d67f159 commit b457490
Show file tree
Hide file tree
Showing 5 changed files with 150 additions and 38 deletions.
3 changes: 3 additions & 0 deletions runtime/bin/BUILD.gn
View file
Original file line number Diff line number Diff line change
Expand Up @@ -228,6 +228,7 @@ template("build_gen_snapshot") {
libs = [
"iphlpapi.lib",
"ws2_32.lib",
"Pathcch.lib",
"Rpcrt4.lib",
"shlwapi.lib",
"winmm.lib",
Expand Down Expand Up @@ -814,6 +815,7 @@ template("dart_executable") {
# CoTaskMemAlloc up with `DynamicLibrary.process()`.
"ole32.lib",
"iphlpapi.lib",
"Pathcch.lib",
"psapi.lib",
"ws2_32.lib",
"Rpcrt4.lib",
Expand Down Expand Up @@ -1032,6 +1034,7 @@ executable("run_vm_tests") {
# CoTaskMemAlloc up with `DynamicLibrary.process()`.
"ole32.lib",
"iphlpapi.lib",
"Pathcch.lib",
"psapi.lib",
"ws2_32.lib",
"Rpcrt4.lib",
Expand Down
78 changes: 60 additions & 18 deletions runtime/bin/file_win.cc
View file
Original file line number Diff line number Diff line change
Expand Up @@ -12,6 +12,7 @@
#include <Shlwapi.h> // NOLINT
#include <fcntl.h> // NOLINT
#include <io.h> // NOLINT
#include <pathcch.h> // NOLINT
#include <winioctl.h> // NOLINT
#undef StrDup // defined in Shlwapi.h as StrDupW
#include <stdio.h> // NOLINT
Expand Down Expand Up @@ -589,22 +590,69 @@ typedef struct _REPARSE_DATA_BUFFER {
};
} REPARSE_DATA_BUFFER, *PREPARSE_DATA_BUFFER;

static constexpr int kReparseDataHeaderSize =
sizeof(ULONG) + 2 * sizeof(USHORT);
static constexpr int kMountPointHeaderSize = 4 * sizeof(USHORT);

bool File::CreateLink(Namespace* namespc,
const char* utf8_name,
const char* utf8_target) {
Utf8ToWideScope name(PrefixLongFilePath(utf8_name));
Utf8ToWideScope target(PrefixLongFilePath(utf8_target));
DWORD flags = SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE;

File::Type type = File::GetType(namespc, utf8_target, true);
File::Type type;
if (File::IsAbsolutePath(utf8_target)) {
type = File::GetType(namespc, utf8_target, true);
} else {
// The path of `target` is relative to `name`.
//
// To determine if `target` is a file or directory, we need to calculate
// either its absolute path or its path relative to the current working
// directory.
//
// For example:
//
// name= C:\A\B\Link ..\..\Link ..\..\Link
// target= MyFile MyFile ..\Dir\MyFile
// --------------------------------------------------------------------
// target_path= C:\A\B\MyFile ..\..\MyFile ..\..\..\Dir\MyFile
//
// The transformation steps are:
// 1. target_path := name ..\..\Link
// 2. target_path := remove_file(target_path) ..\..\
// 3. target_path := combine(target_path, target) ..\..\..\Dir\MyFile

// 1. target_path := name
intptr_t target_path_max_length = name.length() + target.length();
Wchart target_path(target_path_max_length);
wcscpy_s(target_path.buf(), target_path_max_length, name.wide());

// 2. target_path := remove_file(target_path)
HRESULT remove_result =
PathCchRemoveFileSpec(target_path.buf(), target_path_max_length);
if (remove_result == S_FALSE) {
// If the file component could not be removed, then `name` is
// top-level, like "C:\" or "/". Attempts to create files at those paths
// will fail with ERROR_ACCESS_DENIED.
SetLastError(ERROR_ACCESS_DENIED);
return false;
} else if (remove_result != S_OK) {
SetLastError(remove_result);
return false;
}

// 3. target_path := combine(target_path, target)
HRESULT combine_result = PathCchCombineEx(
target_path.buf(), target_path_max_length, target_path.buf(),
target.wide(), PATHCCH_ALLOW_LONG_PATHS);
if (combine_result != S_OK) {
SetLastError(combine_result);
return false;
}

type = PathIsDirectoryW(target_path.buf()) ? kIsDirectory : kIsFile;
}

if (type == kIsDirectory) {
flags |= SYMBOLIC_LINK_FLAG_DIRECTORY;
}

int create_status = CreateSymbolicLinkW(name.wide(), target.wide(), flags);

// If running on a Windows 10 build older than 14972, an invalid parameter
Expand Down Expand Up @@ -1120,40 +1168,34 @@ File::Type File::GetType(Namespace* namespc,
// Convert to wchar_t string.
Utf8ToWideScope name(prefixed_path);
DWORD attributes = GetFileAttributesW(name.wide());
File::Type result = kIsFile;
if (attributes == INVALID_FILE_ATTRIBUTES) {
result = kDoesNotExist;
return kDoesNotExist;
} else if ((attributes & FILE_ATTRIBUTE_REPARSE_POINT) != 0) {
if (follow_links) {
HANDLE target_handle = CreateFileW(
name.wide(), 0,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, nullptr,
OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, nullptr);
if (target_handle == INVALID_HANDLE_VALUE) {
DWORD last_error = GetLastError();
if ((last_error == ERROR_FILE_NOT_FOUND) ||
(last_error == ERROR_PATH_NOT_FOUND)) {
return kDoesNotExist;
}
result = kIsLink;
return kDoesNotExist;
} else {
BY_HANDLE_FILE_INFORMATION info;
if (!GetFileInformationByHandle(target_handle, &info)) {
CloseHandle(target_handle);
return File::kIsLink;
return File::kDoesNotExist;
}
CloseHandle(target_handle);
return ((info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0)
? kIsDirectory
: kIsFile;
}
} else {
result = kIsLink;
return kIsLink;
}
} else if ((attributes & FILE_ATTRIBUTE_DIRECTORY) != 0) {
result = kIsDirectory;
return kIsDirectory;
}
return result;
return kIsFile;
}

File::Identical File::AreIdentical(Namespace* namespc_1,
Expand Down
50 changes: 32 additions & 18 deletions tests/standalone/io/file_long_path_test.dart
View file
Original file line number Diff line number Diff line change
Expand Up @@ -109,31 +109,44 @@ void testFileStat(String dir) {
}

void testCreateLinkToDir(String dir) {
final path = '${dir}\\a_long_path_linkname';
Expect.isTrue(path.length > maxPath);
var target = '$dir\\a_long_path_target';
final link = Link(path)..createSync(target);
final linkPath = '$dir\\a_long_path_linkname';
final renamedPath = '$dir\\a_long_renamed_path_linkname';

final dest = Directory(target)..createSync();
Expect.isTrue(dest.existsSync());
Expect.isTrue(linkPath.length > maxPath);
Expect.isTrue(renamedPath.length > maxPath);

var targetDirectory1 = '$dir\\a_long_directory_target1';
var targetDirectory2 = '$dir\\a_long_directory_target2';

Directory(targetDirectory1).createSync();
Directory(targetDirectory2).createSync();

// Create link
final link = Link(linkPath)..createSync(targetDirectory1);
Expect.isTrue(link.existsSync());
Expect.isTrue(link.targetSync().contains('a_long_path_target'));
final resolvedCreatePath = link.resolveSymbolicLinksSync();
Expect.isTrue(
FileSystemEntity.identicalSync(targetDirectory1, resolvedCreatePath),
'${link.path} should resolve to $targetDirectory1 but resolved to $resolvedCreatePath');

// Rename link
var renamedLink = link.renameSync('${dir}\\a_renamed_long_path_link');
var renamedLink = link.renameSync(renamedPath);
Expect.isTrue(renamedLink.existsSync());
Expect.isFalse(link.existsSync());
Expect.isTrue(renamedLink.targetSync().contains('a_long_path_target'));
final resolvedRenamePath = renamedLink.resolveSymbolicLinksSync();
Expect.isTrue(
FileSystemEntity.identicalSync(targetDirectory1, resolvedRenamePath),
'${link.path} should resolve to $targetDirectory1 but resolved to $resolvedRenamePath');

// Update link target
target = '$dir\\an_updated_target';
final renamedDest = Directory(target)..createSync();
renamedLink.updateSync(target);
Expect.isTrue(renamedLink.targetSync().contains('an_updated_target'));

dest.deleteSync();
renamedDest.deleteSync();
renamedLink.updateSync(targetDirectory2);
final resolvedUpdatedPath = renamedLink.resolveSymbolicLinksSync();
Expect.isTrue(
FileSystemEntity.identicalSync(targetDirectory2, resolvedUpdatedPath),
'${link.path} should resolve to $targetDirectory2 but resolved to $resolvedRenamePath');

Directory(targetDirectory1).deleteSync();
Directory(targetDirectory2).deleteSync();
renamedLink.deleteSync();
}

Expand All @@ -147,8 +160,9 @@ void testCreateLinkToFile(String dir) {
Expect.isTrue(dest.existsSync());

Expect.isTrue(link.existsSync());
Expect.isTrue(link.targetSync().contains('a_long_path_target'));
Expect.isTrue(link.resolveSymbolicLinksSync().contains('a_long_path_target'));
final resolvedPath = link.resolveSymbolicLinksSync();
Expect.isTrue(FileSystemEntity.identicalSync(target, resolvedPath),
'${link.path} should resolve to $target but resolved to $resolvedPath');

// Rename link
var renamedLink = link.renameSync('${dir}\\a_renamed_long_path_link');
Expand Down
31 changes: 29 additions & 2 deletions tests/standalone/io/link_async_test.dart
View file
Original file line number Diff line number Diff line change
Expand Up @@ -280,7 +280,22 @@ Future testRelativeLinks(_) {
});
}

Future testBrokenLinkTypeSync(_) async {
Future testRelativeLinkToDirectoryNotRelativeToCurrentWorkingDirectory(
_) async {
final tempDirectory = await Directory.systemTemp.createTemp('dart_link');
final dir2 = await Directory(join(tempDirectory.path, 'dir1', 'dir2'))
.create(recursive: true);

final link =
await Link(join(tempDirectory.path, 'link')).create(join('dir1', 'dir2'));

String resolvedDir2Path = await link.resolveSymbolicLinks();
Expect.isTrue(await FileSystemEntity.identical(dir2.path, resolvedDir2Path));

await tempDirectory.delete(recursive: true);
}

Future testBrokenLinkType(_) async {
String base = (await Directory.systemTemp.createTemp('dart_link')).path;
String link = join(base, 'link');
await Link(link).create('does not exist');
Expand All @@ -292,12 +307,24 @@ Future testBrokenLinkTypeSync(_) async {
await FileSystemEntity.type(link, followLinks: true));
}

Future testTopLevelLink(_) async {
if (!Platform.isWindows) return;
try {
await Link(r"C:\").create('the target does not matter');
Expect.fail("expected FileSystemException");
} on FileSystemException catch (e) {
Expect.equals(5, e.osError!.errorCode); // ERROR_ACCESS_DENIED
}
}

main() {
asyncStart();
testCreate()
.then(testCreateLoopingLink)
.then(testRename)
.then(testRelativeLinks)
.then(testBrokenLinkTypeSync)
.then(testRelativeLinkToDirectoryNotRelativeToCurrentWorkingDirectory)
.then(testBrokenLinkType)
.then(testTopLevelLink)
.then((_) => asyncEnd());
}
26 changes: 26 additions & 0 deletions tests/standalone/io/link_test.dart
View file
Original file line number Diff line number Diff line change
Expand Up @@ -275,6 +275,20 @@ testRelativeLinksSync() {
tempDirectory.deleteSync(recursive: true);
}

void testRelativeLinkToDirectoryNotRelativeToCurrentWorkingDirectory() {
final tempDirectory = Directory.systemTemp.createTempSync('dart_link');
final dir2 = Directory(join(tempDirectory.path, 'dir1', 'dir2'))
..createSync(recursive: true);

final link = Link(join(tempDirectory.path, 'link'))
..createSync(join('dir1', 'dir2'));

String resolvedDir2Path = link.resolveSymbolicLinksSync();
Expect.isTrue(FileSystemEntity.identicalSync(dir2.path, resolvedDir2Path));

tempDirectory.deleteSync(recursive: true);
}

testIsDir() async {
// Only run on Platforms that supports file watcher
if (!Platform.isWindows && !Platform.isLinux && !Platform.isMacOS) return;
Expand Down Expand Up @@ -326,12 +340,24 @@ testBrokenLinkTypeSync() {
FileSystemEntity.typeSync(link, followLinks: true));
}

void testTopLevelLinkSync() {
if (!Platform.isWindows) return;
try {
Link(r"C:\").createSync('the target does not matter');
Expect.fail("expected FileSystemException");
} on FileSystemException catch (e) {
Expect.equals(5, e.osError!.errorCode); // ERROR_ACCESS_DENIED
}
}

main() {
testCreateSync();
testCreateLoopingLink();
testRenameSync();
testLinkErrorSync();
testRelativeLinksSync();
testRelativeLinkToDirectoryNotRelativeToCurrentWorkingDirectory();
testIsDir();
testBrokenLinkTypeSync();
testTopLevelLinkSync();
}

0 comments on commit b457490

Please sign in to comment.