OSchip
/
llvm-project
mirror of https://github.com/THU-DSP-LAB/llvm-project.git
13
0
Fork 6
Code Issues Packages Projects Releases Wiki Activity
llvm-project/llvm/lib/Support/Windows/Path.inc

1408 lines
47 KiB
C++
Raw Blame History

//===- llvm/Support/Windows/Path.inc - Windows Path Impl --------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Windows specific implementation of the Path API.
//
//===----------------------------------------------------------------------===//
//===----------------------------------------------------------------------===//
//=== WARNING: Implementation here must contain only generic Windows code that
//=== is guaranteed to work on *all* Windows variants.
//===----------------------------------------------------------------------===//
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/ConvertUTF.h"
#include "llvm/Support/WindowsError.h"
#include <fcntl.h>
#include <io.h>
#include <sys/stat.h>
#include <sys/types.h>
// These two headers must be included last, and make sure shlobj is required
// after Windows.h to make sure it picks up our definition of _WIN32_WINNT
#include "WindowsSupport.h"
#include <shellapi.h>
#include <shlobj.h>
#undef max
// MinGW doesn't define this.
#ifndef _ERRNO_T_DEFINED
#define _ERRNO_T_DEFINED
typedef int errno_t;
#endif
#ifdef _MSC_VER
# pragma comment(lib, "advapi32.lib") // This provides CryptAcquireContextW.
# pragma comment(lib, "ole32.lib") // This provides CoTaskMemFree
#endif
using namespace llvm;
using llvm::sys::windows::UTF8ToUTF16;
using llvm::sys::windows::CurCPToUTF16;
using llvm::sys::windows::UTF16ToUTF8;
using llvm::sys::path::widenPath;
static bool is_separator(const wchar_t value) {
switch (value) {
case L'\\':
case L'/':
return true;
default:
return false;
}
}
namespace llvm {
namespace sys {
namespace path {
// Convert a UTF-8 path to UTF-16. Also, if the absolute equivalent of the
// path is longer than CreateDirectory can tolerate, make it absolute and
// prefixed by '\\?\'.
std::error_code widenPath(const Twine &Path8,
SmallVectorImpl<wchar_t> &Path16) {
const size_t MaxDirLen = MAX_PATH - 12; // Must leave room for 8.3 filename.
// Several operations would convert Path8 to SmallString; more efficient to
// do it once up front.
SmallString<128> Path8Str;
Path8.toVector(Path8Str);
// If we made this path absolute, how much longer would it get?
size_t CurPathLen;
if (llvm::sys::path::is_absolute(Twine(Path8Str)))
CurPathLen = 0; // No contribution from current_path needed.
else {
CurPathLen = ::GetCurrentDirectoryW(0, NULL);
if (CurPathLen == 0)
return mapWindowsError(::GetLastError());
}
// Would the absolute path be longer than our limit?
if ((Path8Str.size() + CurPathLen) >= MaxDirLen &&
!Path8Str.startswith("\\\\?\\")) {
SmallString<2*MAX_PATH> FullPath("\\\\?\\");
if (CurPathLen) {
SmallString<80> CurPath;
if (std::error_code EC = llvm::sys::fs::current_path(CurPath))
return EC;
FullPath.append(CurPath);
}
// Traverse the requested path, canonicalizing . and .. (because the \\?\
// prefix is documented to treat them as real components). Ignore
// separators, which can be returned from the iterator if the path has a
// drive name. We don't need to call native() on the result since append()
// always attaches preferred_separator.
for (llvm::sys::path::const_iterator I = llvm::sys::path::begin(Path8Str),
E = llvm::sys::path::end(Path8Str);
I != E; ++I) {
if (I->size() == 1 && is_separator((*I)[0]))
continue;
if (I->size() == 1 && *I == ".")
continue;
if (I->size() == 2 && *I == "..")
llvm::sys::path::remove_filename(FullPath);
else
llvm::sys::path::append(FullPath, *I);
}
return UTF8ToUTF16(FullPath, Path16);
}
// Just use the caller's original path.
return UTF8ToUTF16(Path8Str, Path16);
}
} // end namespace path
namespace fs {
const file_t kInvalidFile = INVALID_HANDLE_VALUE;
std::string getMainExecutable(const char *argv0, void *MainExecAddr) {
SmallVector<wchar_t, MAX_PATH> PathName;
DWORD Size = ::GetModuleFileNameW(NULL, PathName.data(), PathName.capacity());
// A zero return value indicates a failure other than insufficient space.
if (Size == 0)
return "";
// Insufficient space is determined by a return value equal to the size of
// the buffer passed in.
if (Size == PathName.capacity())
return "";
// On success, GetModuleFileNameW returns the number of characters written to
// the buffer not including the NULL terminator.
PathName.set_size(Size);
// Convert the result from UTF-16 to UTF-8.
SmallVector<char, MAX_PATH> PathNameUTF8;
if (UTF16ToUTF8(PathName.data(), PathName.size(), PathNameUTF8))
return "";
return std::string(PathNameUTF8.data());
}
UniqueID file_status::getUniqueID() const {
// The file is uniquely identified by the volume serial number along
// with the 64-bit file identifier.
uint64_t FileID = (static_cast<uint64_t>(FileIndexHigh) << 32ULL) |
static_cast<uint64_t>(FileIndexLow);
return UniqueID(VolumeSerialNumber, FileID);
}
ErrorOr<space_info> disk_space(const Twine &Path) {
ULARGE_INTEGER Avail, Total, Free;
if (!::GetDiskFreeSpaceExA(Path.str().c_str(), &Avail, &Total, &Free))
return mapWindowsError(::GetLastError());
space_info SpaceInfo;
SpaceInfo.capacity =
(static_cast<uint64_t>(Total.HighPart) << 32) + Total.LowPart;
SpaceInfo.free = (static_cast<uint64_t>(Free.HighPart) << 32) + Free.LowPart;
SpaceInfo.available =
(static_cast<uint64_t>(Avail.HighPart) << 32) + Avail.LowPart;
return SpaceInfo;
}
TimePoint<> basic_file_status::getLastAccessedTime() const {
FILETIME Time;
Time.dwLowDateTime = LastAccessedTimeLow;
Time.dwHighDateTime = LastAccessedTimeHigh;
return toTimePoint(Time);
}
TimePoint<> basic_file_status::getLastModificationTime() const {
FILETIME Time;
Time.dwLowDateTime = LastWriteTimeLow;
Time.dwHighDateTime = LastWriteTimeHigh;
return toTimePoint(Time);
}
uint32_t file_status::getLinkCount() const {
return NumLinks;
}
std::error_code current_path(SmallVectorImpl<char> &result) {
SmallVector<wchar_t, MAX_PATH> cur_path;
DWORD len = MAX_PATH;
do {
cur_path.reserve(len);
len = ::GetCurrentDirectoryW(cur_path.capacity(), cur_path.data());
// A zero return value indicates a failure other than insufficient space.
if (len == 0)
return mapWindowsError(::GetLastError());
// If there's insufficient space, the len returned is larger than the len
// given.
} while (len > cur_path.capacity());
// On success, GetCurrentDirectoryW returns the number of characters not
// including the null-terminator.
cur_path.set_size(len);
return UTF16ToUTF8(cur_path.begin(), cur_path.size(), result);
}
std::error_code set_current_path(const Twine &path) {
// Convert to utf-16.
SmallVector<wchar_t, 128> wide_path;
if (std::error_code ec = widenPath(path, wide_path))
return ec;
if (!::SetCurrentDirectoryW(wide_path.begin()))
return mapWindowsError(::GetLastError());
return std::error_code();
}
std::error_code create_directory(const Twine &path, bool IgnoreExisting,
perms Perms) {
SmallVector<wchar_t, 128> path_utf16;
if (std::error_code ec = widenPath(path, path_utf16))
return ec;
if (!::CreateDirectoryW(path_utf16.begin(), NULL)) {
DWORD LastError = ::GetLastError();
if (LastError != ERROR_ALREADY_EXISTS || !IgnoreExisting)
return mapWindowsError(LastError);
}
return std::error_code();
}
// We can't use symbolic links for windows.
std::error_code create_link(const Twine &to, const Twine &from) {
// Convert to utf-16.
SmallVector<wchar_t, 128> wide_from;
SmallVector<wchar_t, 128> wide_to;
if (std::error_code ec = widenPath(from, wide_from))
return ec;
if (std::error_code ec = widenPath(to, wide_to))
return ec;
if (!::CreateHardLinkW(wide_from.begin(), wide_to.begin(), NULL))
return mapWindowsError(::GetLastError());
return std::error_code();
}
std::error_code create_hard_link(const Twine &to, const Twine &from) {
return create_link(to, from);
}
std::error_code remove(const Twine &path, bool IgnoreNonExisting) {
SmallVector<wchar_t, 128> path_utf16;
if (std::error_code ec = widenPath(path, path_utf16))
return ec;
// We don't know whether this is a file or a directory, and remove() can
// accept both. The usual way to delete a file or directory is to use one of
// the DeleteFile or RemoveDirectory functions, but that requires you to know
// which one it is. We could stat() the file to determine that, but that would
// cost us additional system calls, which can be slow in a directory
// containing a large number of files. So instead we call CreateFile directly.
// The important part is the FILE_FLAG_DELETE_ON_CLOSE flag, which causes the
// file to be deleted once it is closed. We also use the flags
// FILE_FLAG_BACKUP_SEMANTICS (which allows us to open directories), and
// FILE_FLAG_OPEN_REPARSE_POINT (don't follow symlinks).
ScopedFileHandle h(::CreateFileW(
c_str(path_utf16), DELETE,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL | FILE_FLAG_BACKUP_SEMANTICS |
FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_DELETE_ON_CLOSE,
NULL));
if (!h) {
std::error_code EC = mapWindowsError(::GetLastError());
if (EC != errc::no_such_file_or_directory || !IgnoreNonExisting)
return EC;
}
return std::error_code();
}
static std::error_code is_local_internal(SmallVectorImpl<wchar_t> &Path,
bool &Result) {
SmallVector<wchar_t, 128> VolumePath;
size_t Len = 128;
while (true) {
VolumePath.resize(Len);
BOOL Success =
::GetVolumePathNameW(Path.data(), VolumePath.data(), VolumePath.size());
if (Success)
break;
DWORD Err = ::GetLastError();
if (Err != ERROR_INSUFFICIENT_BUFFER)
return mapWindowsError(Err);
Len *= 2;
}
// If the output buffer has exactly enough space for the path name, but not
// the null terminator, it will leave the output unterminated. Push a null
// terminator onto the end to ensure that this never happens.
VolumePath.push_back(L'\0');
VolumePath.set_size(wcslen(VolumePath.data()));
const wchar_t *P = VolumePath.data();
UINT Type = ::GetDriveTypeW(P);
switch (Type) {
case DRIVE_FIXED:
Result = true;
return std::error_code();
case DRIVE_REMOTE:
case DRIVE_CDROM:
case DRIVE_RAMDISK:
case DRIVE_REMOVABLE:
Result = false;
return std::error_code();
default:
return make_error_code(errc::no_such_file_or_directory);
}
llvm_unreachable("Unreachable!");
}
std::error_code is_local(const Twine &path, bool &result) {
if (!llvm::sys::fs::exists(path) || !llvm::sys::path::has_root_path(path))
return make_error_code(errc::no_such_file_or_directory);
SmallString<128> Storage;
StringRef P = path.toStringRef(Storage);
// Convert to utf-16.
SmallVector<wchar_t, 128> WidePath;
if (std::error_code ec = widenPath(P, WidePath))
return ec;
return is_local_internal(WidePath, result);
}
static std::error_code realPathFromHandle(HANDLE H,
SmallVectorImpl<wchar_t> &Buffer) {
DWORD CountChars = ::GetFinalPathNameByHandleW(
H, Buffer.begin(), Buffer.capacity() - 1, FILE_NAME_NORMALIZED);
if (CountChars > Buffer.capacity()) {
// The buffer wasn't big enough, try again. In this case the return value
// *does* indicate the size of the null terminator.
Buffer.reserve(CountChars);
CountChars = ::GetFinalPathNameByHandleW(
H, Buffer.data(), Buffer.capacity() - 1, FILE_NAME_NORMALIZED);
}
if (CountChars == 0)
return mapWindowsError(GetLastError());
Buffer.set_size(CountChars);
return std::error_code();
}
static std::error_code realPathFromHandle(HANDLE H,
SmallVectorImpl<char> &RealPath) {
RealPath.clear();
SmallVector<wchar_t, MAX_PATH> Buffer;
if (std::error_code EC = realPathFromHandle(H, Buffer))
return EC;
const wchar_t *Data = Buffer.data();
DWORD CountChars = Buffer.size();
if (CountChars >= 4) {
if (0 == ::memcmp(Data, L"\\\\?\\", 8)) {
CountChars -= 4;
Data += 4;
}
}
// Convert the result from UTF-16 to UTF-8.
return UTF16ToUTF8(Data, CountChars, RealPath);
}
std::error_code is_local(int FD, bool &Result) {
SmallVector<wchar_t, 128> FinalPath;
HANDLE Handle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
if (std::error_code EC = realPathFromHandle(Handle, FinalPath))
return EC;
return is_local_internal(FinalPath, Result);
}
static std::error_code setDeleteDisposition(HANDLE Handle, bool Delete) {
FILE_DISPOSITION_INFO Disposition;
Disposition.DeleteFile = Delete;
if (!SetFileInformationByHandle(Handle, FileDispositionInfo, &Disposition,
sizeof(Disposition)))
return mapWindowsError(::GetLastError());
return std::error_code();
}
static std::error_code rename_internal(HANDLE FromHandle, const Twine &To,
bool ReplaceIfExists) {
SmallVector<wchar_t, 0> ToWide;
if (auto EC = widenPath(To, ToWide))
return EC;
std::vector<char> RenameInfoBuf(sizeof(FILE_RENAME_INFO) - sizeof(wchar_t) +
(ToWide.size() * sizeof(wchar_t)));
FILE_RENAME_INFO &RenameInfo =
*reinterpret_cast<FILE_RENAME_INFO *>(RenameInfoBuf.data());
RenameInfo.ReplaceIfExists = ReplaceIfExists;
RenameInfo.RootDirectory = 0;
RenameInfo.FileNameLength = ToWide.size();
std::copy(ToWide.begin(), ToWide.end(), &RenameInfo.FileName[0]);
SetLastError(ERROR_SUCCESS);
if (!SetFileInformationByHandle(FromHandle, FileRenameInfo, &RenameInfo,
RenameInfoBuf.size())) {
unsigned Error = GetLastError();
if (Error == ERROR_SUCCESS)
Error = ERROR_CALL_NOT_IMPLEMENTED; // Wine doesn't always set error code.
return mapWindowsError(Error);
}
return std::error_code();
}
static std::error_code rename_handle(HANDLE FromHandle, const Twine &To) {
SmallVector<wchar_t, 128> WideTo;
if (std::error_code EC = widenPath(To, WideTo))
return EC;
// We normally expect this loop to succeed after a few iterations. If it
// requires more than 200 tries, it's more likely that the failures are due to
// a true error, so stop trying.
for (unsigned Retry = 0; Retry != 200; ++Retry) {
auto EC = rename_internal(FromHandle, To, true);
if (EC ==
std::error_code(ERROR_CALL_NOT_IMPLEMENTED, std::system_category())) {
// Wine doesn't support SetFileInformationByHandle in rename_internal.
// Fall back to MoveFileEx.
SmallVector<wchar_t, MAX_PATH> WideFrom;
if (std::error_code EC2 = realPathFromHandle(FromHandle, WideFrom))
return EC2;
if (::MoveFileExW(WideFrom.begin(), WideTo.begin(),
MOVEFILE_REPLACE_EXISTING))
return std::error_code();
return mapWindowsError(GetLastError());
}
if (!EC || EC != errc::permission_denied)
return EC;
// The destination file probably exists and is currently open in another
// process, either because the file was opened without FILE_SHARE_DELETE or
// it is mapped into memory (e.g. using MemoryBuffer). Rename it in order to
// move it out of the way of the source file. Use FILE_FLAG_DELETE_ON_CLOSE
// to arrange for the destination file to be deleted when the other process
// closes it.
ScopedFileHandle ToHandle(
::CreateFileW(WideTo.begin(), GENERIC_READ | DELETE,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
NULL, OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL | FILE_FLAG_DELETE_ON_CLOSE, NULL));
if (!ToHandle) {
auto EC = mapWindowsError(GetLastError());
// Another process might have raced with us and moved the existing file
// out of the way before we had a chance to open it. If that happens, try
// to rename the source file again.
if (EC == errc::no_such_file_or_directory)
continue;
return EC;
}
BY_HANDLE_FILE_INFORMATION FI;
if (!GetFileInformationByHandle(ToHandle, &FI))
return mapWindowsError(GetLastError());
// Try to find a unique new name for the destination file.
for (unsigned UniqueId = 0; UniqueId != 200; ++UniqueId) {
std::string TmpFilename = (To + ".tmp" + utostr(UniqueId)).str();
if (auto EC = rename_internal(ToHandle, TmpFilename, false)) {
if (EC == errc::file_exists || EC == errc::permission_denied) {
// Again, another process might have raced with us and moved the file
// before we could move it. Check whether this is the case, as it
// might have caused the permission denied error. If that was the
// case, we don't need to move it ourselves.
ScopedFileHandle ToHandle2(::CreateFileW(
WideTo.begin(), 0,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL));
if (!ToHandle2) {
auto EC = mapWindowsError(GetLastError());
if (EC == errc::no_such_file_or_directory)
break;
return EC;
}
BY_HANDLE_FILE_INFORMATION FI2;
if (!GetFileInformationByHandle(ToHandle2, &FI2))
return mapWindowsError(GetLastError());
if (FI.nFileIndexHigh != FI2.nFileIndexHigh ||
FI.nFileIndexLow != FI2.nFileIndexLow ||
FI.dwVolumeSerialNumber != FI2.dwVolumeSerialNumber)
break;
continue;
}
return EC;
}
break;
}
// Okay, the old destination file has probably been moved out of the way at
// this point, so try to rename the source file again. Still, another
// process might have raced with us to create and open the destination
// file, so we need to keep doing this until we succeed.
}
// The most likely root cause.
return errc::permission_denied;
}
static std::error_code rename_fd(int FromFD, const Twine &To) {
HANDLE FromHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FromFD));
return rename_handle(FromHandle, To);
}
std::error_code rename(const Twine &From, const Twine &To) {
// Convert to utf-16.
SmallVector<wchar_t, 128> WideFrom;
if (std::error_code EC = widenPath(From, WideFrom))
return EC;
ScopedFileHandle FromHandle;
// Retry this a few times to defeat badly behaved file system scanners.
for (unsigned Retry = 0; Retry != 200; ++Retry) {
if (Retry != 0)
::Sleep(10);
FromHandle =
::CreateFileW(WideFrom.begin(), GENERIC_READ | DELETE,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (FromHandle)
break;
}
if (!FromHandle)
return mapWindowsError(GetLastError());
return rename_handle(FromHandle, To);
}
std::error_code resize_file(int FD, uint64_t Size) {
#ifdef HAVE__CHSIZE_S
errno_t error = ::_chsize_s(FD, Size);
#else
errno_t error = ::_chsize(FD, Size);
#endif
return std::error_code(error, std::generic_category());
}
std::error_code access(const Twine &Path, AccessMode Mode) {
SmallVector<wchar_t, 128> PathUtf16;
if (std::error_code EC = widenPath(Path, PathUtf16))
return EC;
DWORD Attributes = ::GetFileAttributesW(PathUtf16.begin());
if (Attributes == INVALID_FILE_ATTRIBUTES) {
// See if the file didn't actually exist.
DWORD LastError = ::GetLastError();
if (LastError != ERROR_FILE_NOT_FOUND &&
LastError != ERROR_PATH_NOT_FOUND)
return mapWindowsError(LastError);
return errc::no_such_file_or_directory;
}
if (Mode == AccessMode::Write && (Attributes & FILE_ATTRIBUTE_READONLY))
return errc::permission_denied;
return std::error_code();
}
bool can_execute(const Twine &Path) {
return !access(Path, AccessMode::Execute) ||
!access(Path + ".exe", AccessMode::Execute);
}
bool equivalent(file_status A, file_status B) {
assert(status_known(A) && status_known(B));
return A.FileIndexHigh == B.FileIndexHigh &&
A.FileIndexLow == B.FileIndexLow &&
A.FileSizeHigh == B.FileSizeHigh &&
A.FileSizeLow == B.FileSizeLow &&
A.LastAccessedTimeHigh == B.LastAccessedTimeHigh &&
A.LastAccessedTimeLow == B.LastAccessedTimeLow &&
A.LastWriteTimeHigh == B.LastWriteTimeHigh &&
A.LastWriteTimeLow == B.LastWriteTimeLow &&
A.VolumeSerialNumber == B.VolumeSerialNumber;
}
std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {
file_status fsA, fsB;
if (std::error_code ec = status(A, fsA))
return ec;
if (std::error_code ec = status(B, fsB))
return ec;
result = equivalent(fsA, fsB);
return std::error_code();
}
static bool isReservedName(StringRef path) {
// This list of reserved names comes from MSDN, at:
// http://msdn.microsoft.com/en-us/library/aa365247%28v=vs.85%29.aspx
static const char *const sReservedNames[] = { "nul", "con", "prn", "aux",
"com1", "com2", "com3", "com4",
"com5", "com6", "com7", "com8",
"com9", "lpt1", "lpt2", "lpt3",
"lpt4", "lpt5", "lpt6", "lpt7",
"lpt8", "lpt9" };
// First, check to see if this is a device namespace, which always
// starts with \\.\, since device namespaces are not legal file paths.
if (path.startswith("\\\\.\\"))
return true;
// Then compare against the list of ancient reserved names.
for (size_t i = 0; i < array_lengthof(sReservedNames); ++i) {
if (path.equals_lower(sReservedNames[i]))
return true;
}
// The path isn't what we consider reserved.
return false;
}
static file_type file_type_from_attrs(DWORD Attrs) {
return (Attrs & FILE_ATTRIBUTE_DIRECTORY) ? file_type::directory_file
: file_type::regular_file;
}
static perms perms_from_attrs(DWORD Attrs) {
return (Attrs & FILE_ATTRIBUTE_READONLY) ? (all_read | all_exe) : all_all;
}
static std::error_code getStatus(HANDLE FileHandle, file_status &Result) {
if (FileHandle == INVALID_HANDLE_VALUE)
goto handle_status_error;
switch (::GetFileType(FileHandle)) {
default:
llvm_unreachable("Don't know anything about this file type");
case FILE_TYPE_UNKNOWN: {
DWORD Err = ::GetLastError();
if (Err != NO_ERROR)
return mapWindowsError(Err);
Result = file_status(file_type::type_unknown);
return std::error_code();
}
case FILE_TYPE_DISK:
break;
case FILE_TYPE_CHAR:
Result = file_status(file_type::character_file);
return std::error_code();
case FILE_TYPE_PIPE:
Result = file_status(file_type::fifo_file);
return std::error_code();
}
BY_HANDLE_FILE_INFORMATION Info;
if (!::GetFileInformationByHandle(FileHandle, &Info))
goto handle_status_error;
Result = file_status(
file_type_from_attrs(Info.dwFileAttributes),
perms_from_attrs(Info.dwFileAttributes), Info.nNumberOfLinks,
Info.ftLastAccessTime.dwHighDateTime, Info.ftLastAccessTime.dwLowDateTime,
Info.ftLastWriteTime.dwHighDateTime, Info.ftLastWriteTime.dwLowDateTime,
Info.dwVolumeSerialNumber, Info.nFileSizeHigh, Info.nFileSizeLow,
Info.nFileIndexHigh, Info.nFileIndexLow);
return std::error_code();
handle_status_error:
DWORD LastError = ::GetLastError();
if (LastError == ERROR_FILE_NOT_FOUND ||
LastError == ERROR_PATH_NOT_FOUND)
Result = file_status(file_type::file_not_found);
else if (LastError == ERROR_SHARING_VIOLATION)
Result = file_status(file_type::type_unknown);
else
Result = file_status(file_type::status_error);
return mapWindowsError(LastError);
}
std::error_code status(const Twine &path, file_status &result, bool Follow) {
SmallString<128> path_storage;
SmallVector<wchar_t, 128> path_utf16;
StringRef path8 = path.toStringRef(path_storage);
if (isReservedName(path8)) {
result = file_status(file_type::character_file);
return std::error_code();
}
if (std::error_code ec = widenPath(path8, path_utf16))
return ec;
DWORD attr = ::GetFileAttributesW(path_utf16.begin());
if (attr == INVALID_FILE_ATTRIBUTES)
return getStatus(INVALID_HANDLE_VALUE, result);
DWORD Flags = FILE_FLAG_BACKUP_SEMANTICS;
// Handle reparse points.
if (!Follow && (attr & FILE_ATTRIBUTE_REPARSE_POINT))
Flags |= FILE_FLAG_OPEN_REPARSE_POINT;
ScopedFileHandle h(
::CreateFileW(path_utf16.begin(), 0, // Attributes only.
FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL, OPEN_EXISTING, Flags, 0));
if (!h)
return getStatus(INVALID_HANDLE_VALUE, result);
return getStatus(h, result);
}
std::error_code status(int FD, file_status &Result) {
HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
return getStatus(FileHandle, Result);
}
std::error_code setPermissions(const Twine &Path, perms Permissions) {
SmallVector<wchar_t, 128> PathUTF16;
if (std::error_code EC = widenPath(Path, PathUTF16))
return EC;
DWORD Attributes = ::GetFileAttributesW(PathUTF16.begin());
if (Attributes == INVALID_FILE_ATTRIBUTES)
return mapWindowsError(GetLastError());
// There are many Windows file attributes that are not to do with the file
// permissions (e.g. FILE_ATTRIBUTE_HIDDEN). We need to be careful to preserve
// them.
if (Permissions & all_write) {
Attributes &= ~FILE_ATTRIBUTE_READONLY;
if (Attributes == 0)
// FILE_ATTRIBUTE_NORMAL indicates no other attributes are set.
Attributes |= FILE_ATTRIBUTE_NORMAL;
}
else {
Attributes |= FILE_ATTRIBUTE_READONLY;
// FILE_ATTRIBUTE_NORMAL is not compatible with any other attributes, so
// remove it, if it is present.
Attributes &= ~FILE_ATTRIBUTE_NORMAL;
}
if (!::SetFileAttributesW(PathUTF16.begin(), Attributes))
return mapWindowsError(GetLastError());
return std::error_code();
}
std::error_code setLastAccessAndModificationTime(int FD, TimePoint<> AccessTime,
TimePoint<> ModificationTime) {
FILETIME AccessFT = toFILETIME(AccessTime);
FILETIME ModifyFT = toFILETIME(ModificationTime);
HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
if (!SetFileTime(FileHandle, NULL, &AccessFT, &ModifyFT))
return mapWindowsError(::GetLastError());
return std::error_code();
}
std::error_code mapped_file_region::init(int FD, uint64_t Offset,
mapmode Mode) {
this->Mode = Mode;
HANDLE OrigFileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
if (OrigFileHandle == INVALID_HANDLE_VALUE)
return make_error_code(errc::bad_file_descriptor);
DWORD flprotect;
switch (Mode) {
case readonly: flprotect = PAGE_READONLY; break;
case readwrite: flprotect = PAGE_READWRITE; break;
case priv: flprotect = PAGE_WRITECOPY; break;
}
HANDLE FileMappingHandle =
::CreateFileMappingW(OrigFileHandle, 0, flprotect,
Hi_32(Size),
Lo_32(Size),
0);
if (FileMappingHandle == NULL) {
std::error_code ec = mapWindowsError(GetLastError());
return ec;
}
DWORD dwDesiredAccess;
switch (Mode) {
case readonly: dwDesiredAccess = FILE_MAP_READ; break;
case readwrite: dwDesiredAccess = FILE_MAP_WRITE; break;
case priv: dwDesiredAccess = FILE_MAP_COPY; break;
}
Mapping = ::MapViewOfFile(FileMappingHandle,
dwDesiredAccess,
Offset >> 32,
Offset & 0xffffffff,
Size);
if (Mapping == NULL) {
std::error_code ec = mapWindowsError(GetLastError());
::CloseHandle(FileMappingHandle);
return ec;
}
if (Size == 0) {
MEMORY_BASIC_INFORMATION mbi;
SIZE_T Result = VirtualQuery(Mapping, &mbi, sizeof(mbi));
if (Result == 0) {
std::error_code ec = mapWindowsError(GetLastError());
::UnmapViewOfFile(Mapping);
::CloseHandle(FileMappingHandle);
return ec;
}
Size = mbi.RegionSize;
}
// Close the file mapping handle, as it's kept alive by the file mapping. But
// neither the file mapping nor the file mapping handle keep the file handle
// alive, so we need to keep a reference to the file in case all other handles
// are closed and the file is deleted, which may cause invalid data to be read
// from the file.
::CloseHandle(FileMappingHandle);
if (!::DuplicateHandle(::GetCurrentProcess(), OrigFileHandle,
::GetCurrentProcess(), &FileHandle, 0, 0,
DUPLICATE_SAME_ACCESS)) {
std::error_code ec = mapWindowsError(GetLastError());
::UnmapViewOfFile(Mapping);
return ec;
}
return std::error_code();
}
mapped_file_region::mapped_file_region(int fd, mapmode mode, size_t length,
uint64_t offset, std::error_code &ec)
: Size(length), Mapping() {
ec = init(fd, offset, mode);
if (ec)
Mapping = 0;
}
mapped_file_region::~mapped_file_region() {
if (Mapping) {
::UnmapViewOfFile(Mapping);
if (Mode == mapmode::readwrite) {
// There is a Windows kernel bug, the exact trigger conditions of which
// are not well understood. When triggered, dirty pages are not properly
// flushed and subsequent process's attempts to read a file can return
// invalid data. Calling FlushFileBuffers on the write handle is
// sufficient to ensure that this bug is not triggered.
::FlushFileBuffers(FileHandle);
}
::CloseHandle(FileHandle);
}
}
size_t mapped_file_region::size() const {
assert(Mapping && "Mapping failed but used anyway!");
return Size;
}
char *mapped_file_region::data() const {
assert(Mapping && "Mapping failed but used anyway!");
return reinterpret_cast<char*>(Mapping);
}
const char *mapped_file_region::const_data() const {
assert(Mapping && "Mapping failed but used anyway!");
return reinterpret_cast<const char*>(Mapping);
}
int mapped_file_region::alignment() {
SYSTEM_INFO SysInfo;
::GetSystemInfo(&SysInfo);
return SysInfo.dwAllocationGranularity;
}
static basic_file_status status_from_find_data(WIN32_FIND_DATAW *FindData) {
return basic_file_status(file_type_from_attrs(FindData->dwFileAttributes),
perms_from_attrs(FindData->dwFileAttributes),
FindData->ftLastAccessTime.dwHighDateTime,
FindData->ftLastAccessTime.dwLowDateTime,
FindData->ftLastWriteTime.dwHighDateTime,
FindData->ftLastWriteTime.dwLowDateTime,
FindData->nFileSizeHigh, FindData->nFileSizeLow);
}
std::error_code detail::directory_iterator_construct(detail::DirIterState &IT,
StringRef Path,
bool FollowSymlinks) {
SmallVector<wchar_t, 128> PathUTF16;
if (std::error_code EC = widenPath(Path, PathUTF16))
return EC;
// Convert path to the format that Windows is happy with.
if (PathUTF16.size() > 0 &&
!is_separator(PathUTF16[Path.size() - 1]) &&
PathUTF16[Path.size() - 1] != L':') {
PathUTF16.push_back(L'\\');
PathUTF16.push_back(L'*');
} else {
PathUTF16.push_back(L'*');
}
// Get the first directory entry.
WIN32_FIND_DATAW FirstFind;
ScopedFindHandle FindHandle(::FindFirstFileExW(
c_str(PathUTF16), FindExInfoBasic, &FirstFind, FindExSearchNameMatch,
NULL, FIND_FIRST_EX_LARGE_FETCH));
if (!FindHandle)
return mapWindowsError(::GetLastError());
size_t FilenameLen = ::wcslen(FirstFind.cFileName);
while ((FilenameLen == 1 && FirstFind.cFileName[0] == L'.') ||
(FilenameLen == 2 && FirstFind.cFileName[0] == L'.' &&
FirstFind.cFileName[1] == L'.'))
if (!::FindNextFileW(FindHandle, &FirstFind)) {
DWORD LastError = ::GetLastError();
// Check for end.
if (LastError == ERROR_NO_MORE_FILES)
return detail::directory_iterator_destruct(IT);
return mapWindowsError(LastError);
} else
FilenameLen = ::wcslen(FirstFind.cFileName);
// Construct the current directory entry.
SmallString<128> DirectoryEntryNameUTF8;
if (std::error_code EC =
UTF16ToUTF8(FirstFind.cFileName, ::wcslen(FirstFind.cFileName),
DirectoryEntryNameUTF8))
return EC;
IT.IterationHandle = intptr_t(FindHandle.take());
SmallString<128> DirectoryEntryPath(Path);
path::append(DirectoryEntryPath, DirectoryEntryNameUTF8);
IT.CurrentEntry =
directory_entry(DirectoryEntryPath, FollowSymlinks,
file_type_from_attrs(FirstFind.dwFileAttributes),
status_from_find_data(&FirstFind));
return std::error_code();
}
std::error_code detail::directory_iterator_destruct(detail::DirIterState &IT) {
if (IT.IterationHandle != 0)
// Closes the handle if it's valid.
ScopedFindHandle close(HANDLE(IT.IterationHandle));
IT.IterationHandle = 0;
IT.CurrentEntry = directory_entry();
return std::error_code();
}
std::error_code detail::directory_iterator_increment(detail::DirIterState &IT) {
WIN32_FIND_DATAW FindData;
if (!::FindNextFileW(HANDLE(IT.IterationHandle), &FindData)) {
DWORD LastError = ::GetLastError();
// Check for end.
if (LastError == ERROR_NO_MORE_FILES)
return detail::directory_iterator_destruct(IT);
return mapWindowsError(LastError);
}
size_t FilenameLen = ::wcslen(FindData.cFileName);
if ((FilenameLen == 1 && FindData.cFileName[0] == L'.') ||
(FilenameLen == 2 && FindData.cFileName[0] == L'.' &&
FindData.cFileName[1] == L'.'))
return directory_iterator_increment(IT);
SmallString<128> DirectoryEntryPathUTF8;
if (std::error_code EC =
UTF16ToUTF8(FindData.cFileName, ::wcslen(FindData.cFileName),
DirectoryEntryPathUTF8))
return EC;
IT.CurrentEntry.replace_filename(
Twine(DirectoryEntryPathUTF8),
file_type_from_attrs(FindData.dwFileAttributes),
status_from_find_data(&FindData));
return std::error_code();
}
ErrorOr<basic_file_status> directory_entry::status() const {
return Status;
}
static std::error_code nativeFileToFd(Expected<HANDLE> H, int &ResultFD,
OpenFlags Flags) {
int CrtOpenFlags = 0;
if (Flags & OF_Append)
CrtOpenFlags |= _O_APPEND;
if (Flags & OF_Text)
CrtOpenFlags |= _O_TEXT;
ResultFD = -1;
if (!H)
return errorToErrorCode(H.takeError());
ResultFD = ::_open_osfhandle(intptr_t(*H), CrtOpenFlags);
if (ResultFD == -1) {
::CloseHandle(*H);
return mapWindowsError(ERROR_INVALID_HANDLE);
}
return std::error_code();
}
static DWORD nativeDisposition(CreationDisposition Disp, OpenFlags Flags) {
// This is a compatibility hack. Really we should respect the creation
// disposition, but a lot of old code relied on the implicit assumption that
// OF_Append implied it would open an existing file. Since the disposition is
// now explicit and defaults to CD_CreateAlways, this assumption would cause
// any usage of OF_Append to append to a new file, even if the file already
// existed. A better solution might have two new creation dispositions:
// CD_AppendAlways and CD_AppendNew. This would also address the problem of
// OF_Append being used on a read-only descriptor, which doesn't make sense.
if (Flags & OF_Append)
return OPEN_ALWAYS;
switch (Disp) {
case CD_CreateAlways:
return CREATE_ALWAYS;
case CD_CreateNew:
return CREATE_NEW;
case CD_OpenAlways:
return OPEN_ALWAYS;
case CD_OpenExisting:
return OPEN_EXISTING;
}
llvm_unreachable("unreachable!");
}
static DWORD nativeAccess(FileAccess Access, OpenFlags Flags) {
DWORD Result = 0;
if (Access & FA_Read)
Result |= GENERIC_READ;
if (Access & FA_Write)
Result |= GENERIC_WRITE;
if (Flags & OF_Delete)
Result |= DELETE;
if (Flags & OF_UpdateAtime)
Result |= FILE_WRITE_ATTRIBUTES;
return Result;
}
static std::error_code openNativeFileInternal(const Twine &Name,
file_t &ResultFile, DWORD Disp,
DWORD Access, DWORD Flags,
bool Inherit = false) {
SmallVector<wchar_t, 128> PathUTF16;
if (std::error_code EC = widenPath(Name, PathUTF16))
return EC;
SECURITY_ATTRIBUTES SA;
SA.nLength = sizeof(SA);
SA.lpSecurityDescriptor = nullptr;
SA.bInheritHandle = Inherit;
HANDLE H =
::CreateFileW(PathUTF16.begin(), Access,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, &SA,
Disp, Flags, NULL);
if (H == INVALID_HANDLE_VALUE) {
DWORD LastError = ::GetLastError();
std::error_code EC = mapWindowsError(LastError);
// Provide a better error message when trying to open directories.
// This only runs if we failed to open the file, so there is probably
// no performances issues.
if (LastError != ERROR_ACCESS_DENIED)
return EC;
if (is_directory(Name))
return make_error_code(errc::is_a_directory);
return EC;
}
ResultFile = H;
return std::error_code();
}
Expected<file_t> openNativeFile(const Twine &Name, CreationDisposition Disp,
FileAccess Access, OpenFlags Flags,
unsigned Mode) {
// Verify that we don't have both "append" and "excl".
assert((!(Disp == CD_CreateNew) || !(Flags & OF_Append)) &&
"Cannot specify both 'CreateNew' and 'Append' file creation flags!");
DWORD NativeDisp = nativeDisposition(Disp, Flags);
DWORD NativeAccess = nativeAccess(Access, Flags);
bool Inherit = false;
if (Flags & OF_ChildInherit)
Inherit = true;
file_t Result;
std::error_code EC = openNativeFileInternal(
Name, Result, NativeDisp, NativeAccess, FILE_ATTRIBUTE_NORMAL, Inherit);
if (EC)
return errorCodeToError(EC);
if (Flags & OF_UpdateAtime) {
FILETIME FileTime;
SYSTEMTIME SystemTime;
GetSystemTime(&SystemTime);
if (SystemTimeToFileTime(&SystemTime, &FileTime) == 0 ||
SetFileTime(Result, NULL, &FileTime, NULL) == 0) {
DWORD LastError = ::GetLastError();
::CloseHandle(Result);
return errorCodeToError(mapWindowsError(LastError));
}
}
if (Flags & OF_Delete) {
if ((EC = setDeleteDisposition(Result, true))) {
::CloseHandle(Result);
return errorCodeToError(EC);
}
}
return Result;
}
std::error_code openFile(const Twine &Name, int &ResultFD,
CreationDisposition Disp, FileAccess Access,
OpenFlags Flags, unsigned int Mode) {
Expected<file_t> Result = openNativeFile(Name, Disp, Access, Flags);
if (!Result)
return errorToErrorCode(Result.takeError());
return nativeFileToFd(*Result, ResultFD, Flags);
}
static std::error_code directoryRealPath(const Twine &Name,
SmallVectorImpl<char> &RealPath) {
file_t File;
std::error_code EC = openNativeFileInternal(
Name, File, OPEN_EXISTING, GENERIC_READ, FILE_FLAG_BACKUP_SEMANTICS);
if (EC)
return EC;
EC = realPathFromHandle(File, RealPath);
::CloseHandle(File);
return EC;
}
std::error_code openFileForRead(const Twine &Name, int &ResultFD,
OpenFlags Flags,
SmallVectorImpl<char> *RealPath) {
Expected<HANDLE> NativeFile = openNativeFileForRead(Name, Flags, RealPath);
return nativeFileToFd(std::move(NativeFile), ResultFD, OF_None);
}
Expected<file_t> openNativeFileForRead(const Twine &Name, OpenFlags Flags,
SmallVectorImpl<char> *RealPath) {
Expected<file_t> Result =
openNativeFile(Name, CD_OpenExisting, FA_Read, Flags);
// Fetch the real name of the file, if the user asked
if (Result && RealPath)
realPathFromHandle(*Result, *RealPath);
return Result;
}
void closeFile(file_t &F) {
::CloseHandle(F);
F = kInvalidFile;
}
std::error_code remove_directories(const Twine &path, bool IgnoreErrors) {
// Convert to utf-16.
SmallVector<wchar_t, 128> Path16;
std::error_code EC = widenPath(path, Path16);
if (EC && !IgnoreErrors)
return EC;
// SHFileOperation() accepts a list of paths, and so must be double null-
// terminated to indicate the end of the list. The buffer is already null
// terminated, but since that null character is not considered part of the
// vector's size, pushing another one will just consume that byte. So we
// need to push 2 null terminators.
Path16.push_back(0);
Path16.push_back(0);
SHFILEOPSTRUCTW shfos = {};
shfos.wFunc = FO_DELETE;
shfos.pFrom = Path16.data();
shfos.fFlags = FOF_NO_UI;
int result = ::SHFileOperationW(&shfos);
if (result != 0 && !IgnoreErrors)
return mapWindowsError(result);
return std::error_code();
}
static void expandTildeExpr(SmallVectorImpl<char> &Path) {
// Path does not begin with a tilde expression.
if (Path.empty() || Path[0] != '~')
return;
StringRef PathStr(Path.begin(), Path.size());
PathStr = PathStr.drop_front();
StringRef Expr = PathStr.take_until([](char c) { return path::is_separator(c); });
if (!Expr.empty()) {
// This is probably a ~username/ expression. Don't support this on Windows.
return;
}
SmallString<128> HomeDir;
if (!path::home_directory(HomeDir)) {
// For some reason we couldn't get the home directory. Just exit.
return;
}
// Overwrite the first character and insert the rest.
Path[0] = HomeDir[0];
Path.insert(Path.begin() + 1, HomeDir.begin() + 1, HomeDir.end());
}
std::error_code real_path(const Twine &path, SmallVectorImpl<char> &dest,
bool expand_tilde) {
dest.clear();
if (path.isTriviallyEmpty())
return std::error_code();
if (expand_tilde) {
SmallString<128> Storage;
path.toVector(Storage);
expandTildeExpr(Storage);
return real_path(Storage, dest, false);
}
if (is_directory(path))
return directoryRealPath(path, dest);
int fd;
if (std::error_code EC =
llvm::sys::fs::openFileForRead(path, fd, OF_None, &dest))
return EC;
::close(fd);
return std::error_code();
}
} // end namespace fs
namespace path {
static bool getKnownFolderPath(KNOWNFOLDERID folderId,
SmallVectorImpl<char> &result) {
wchar_t *path = nullptr;
if (::SHGetKnownFolderPath(folderId, KF_FLAG_CREATE, nullptr, &path) != S_OK)
return false;
bool ok = !UTF16ToUTF8(path, ::wcslen(path), result);
::CoTaskMemFree(path);
return ok;
}
bool home_directory(SmallVectorImpl<char> &result) {
return getKnownFolderPath(FOLDERID_Profile, result);
}
static bool getTempDirEnvVar(const wchar_t *Var, SmallVectorImpl<char> &Res) {
SmallVector<wchar_t, 1024> Buf;
size_t Size = 1024;
do {
Buf.reserve(Size);
Size = GetEnvironmentVariableW(Var, Buf.data(), Buf.capacity());
if (Size == 0)
return false;
// Try again with larger buffer.
} while (Size > Buf.capacity());
Buf.set_size(Size);
return !windows::UTF16ToUTF8(Buf.data(), Size, Res);
}
static bool getTempDirEnvVar(SmallVectorImpl<char> &Res) {
const wchar_t *EnvironmentVariables[] = {L"TMP", L"TEMP", L"USERPROFILE"};
for (auto *Env : EnvironmentVariables) {
if (getTempDirEnvVar(Env, Res))
return true;
}
return false;
}
void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
(void)ErasedOnReboot;
Result.clear();
// Check whether the temporary directory is specified by an environment var.
// This matches GetTempPath logic to some degree. GetTempPath is not used
// directly as it cannot handle evn var longer than 130 chars on Windows 7
// (fixed on Windows 8).
if (getTempDirEnvVar(Result)) {
assert(!Result.empty() && "Unexpected empty path");
native(Result); // Some Unix-like shells use Unix path separator in $TMP.
fs::make_absolute(Result); // Make it absolute if not already.
return;
}
// Fall back to a system default.
const char *DefaultResult = "C:\\Temp";
Result.append(DefaultResult, DefaultResult + strlen(DefaultResult));
}
} // end namespace path
namespace windows {
std::error_code CodePageToUTF16(unsigned codepage,
llvm::StringRef original,
llvm::SmallVectorImpl<wchar_t> &utf16) {
if (!original.empty()) {
int len = ::MultiByteToWideChar(codepage, MB_ERR_INVALID_CHARS, original.begin(),
original.size(), utf16.begin(), 0);
if (len == 0) {
return mapWindowsError(::GetLastError());
}
utf16.reserve(len + 1);
utf16.set_size(len);
len = ::MultiByteToWideChar(codepage, MB_ERR_INVALID_CHARS, original.begin(),
original.size(), utf16.begin(), utf16.size());
if (len == 0) {
return mapWindowsError(::GetLastError());
}
}
// Make utf16 null terminated.
utf16.push_back(0);
utf16.pop_back();
return std::error_code();
}
std::error_code UTF8ToUTF16(llvm::StringRef utf8,
llvm::SmallVectorImpl<wchar_t> &utf16) {
return CodePageToUTF16(CP_UTF8, utf8, utf16);
}
std::error_code CurCPToUTF16(llvm::StringRef curcp,
llvm::SmallVectorImpl<wchar_t> &utf16) {
return CodePageToUTF16(CP_ACP, curcp, utf16);
}
static
std::error_code UTF16ToCodePage(unsigned codepage, const wchar_t *utf16,
size_t utf16_len,
llvm::SmallVectorImpl<char> &converted) {
if (utf16_len) {
// Get length.
int len = ::WideCharToMultiByte(codepage, 0, utf16, utf16_len, converted.begin(),
0, NULL, NULL);
if (len == 0) {
return mapWindowsError(::GetLastError());
}
converted.reserve(len);
converted.set_size(len);
// Now do the actual conversion.
len = ::WideCharToMultiByte(codepage, 0, utf16, utf16_len, converted.data(),
converted.size(), NULL, NULL);
if (len == 0) {
return mapWindowsError(::GetLastError());
}
}
// Make the new string null terminated.
converted.push_back(0);
converted.pop_back();
return std::error_code();
}
std::error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len,
llvm::SmallVectorImpl<char> &utf8) {
return UTF16ToCodePage(CP_UTF8, utf16, utf16_len, utf8);
}
std::error_code UTF16ToCurCP(const wchar_t *utf16, size_t utf16_len,
llvm::SmallVectorImpl<char> &curcp) {
return UTF16ToCodePage(CP_ACP, utf16, utf16_len, curcp);
}
} // end namespace windows
} // end namespace sys
} // end namespace llvm
Reference in New Issue View Git Blame Copy Permalink