diff options
Diffstat (limited to 'library/std/src/sys/pal/windows/fs.rs')
| -rw-r--r-- | library/std/src/sys/pal/windows/fs.rs | 185 |
1 files changed, 60 insertions, 125 deletions
diff --git a/library/std/src/sys/pal/windows/fs.rs b/library/std/src/sys/pal/windows/fs.rs index f8493c21ad4..7fedf15dad5 100644 --- a/library/std/src/sys/pal/windows/fs.rs +++ b/library/std/src/sys/pal/windows/fs.rs @@ -1,10 +1,10 @@ use super::api::{self, WinError}; use super::{IoResult, to_u16s}; -use crate::alloc::{alloc, handle_alloc_error}; +use crate::alloc::{Layout, alloc, dealloc}; use crate::borrow::Cow; use crate::ffi::{OsStr, OsString, c_void}; use crate::io::{self, BorrowedCursor, Error, IoSlice, IoSliceMut, SeekFrom}; -use crate::mem::{self, MaybeUninit}; +use crate::mem::{self, MaybeUninit, offset_of}; use crate::os::windows::io::{AsHandle, BorrowedHandle}; use crate::os::windows::prelude::*; use crate::path::{Path, PathBuf}; @@ -296,6 +296,10 @@ impl OpenOptions { impl File { pub fn open(path: &Path, opts: &OpenOptions) -> io::Result<File> { let path = maybe_verbatim(path)?; + Self::open_native(&path, opts) + } + + fn open_native(path: &[u16], opts: &OpenOptions) -> io::Result<File> { let creation = opts.get_creation_mode()?; let handle = unsafe { c::CreateFileW( @@ -1234,141 +1238,72 @@ pub fn rename(old: &Path, new: &Path) -> io::Result<()> { let old = maybe_verbatim(old)?; let new = maybe_verbatim(new)?; - let new_len_without_nul_in_bytes = (new.len() - 1).try_into().unwrap(); - - // The last field of FILE_RENAME_INFO, the file name, is unsized, - // and FILE_RENAME_INFO has two padding bytes. - // Therefore we need to make sure to not allocate less than - // size_of::<c::FILE_RENAME_INFO>() bytes, which would be the case with - // 0 or 1 character paths + a null byte. - let struct_size = mem::size_of::<c::FILE_RENAME_INFO>() - .max(mem::offset_of!(c::FILE_RENAME_INFO, FileName) + new.len() * mem::size_of::<u16>()); - - let struct_size: u32 = struct_size.try_into().unwrap(); - - let create_file = |extra_access, extra_flags| { - let handle = unsafe { - HandleOrInvalid::from_raw_handle(c::CreateFileW( - old.as_ptr(), - c::SYNCHRONIZE | c::DELETE | extra_access, - c::FILE_SHARE_READ | c::FILE_SHARE_WRITE | c::FILE_SHARE_DELETE, - ptr::null(), - c::OPEN_EXISTING, - c::FILE_ATTRIBUTE_NORMAL | c::FILE_FLAG_BACKUP_SEMANTICS | extra_flags, - ptr::null_mut(), - )) - }; - - OwnedHandle::try_from(handle).map_err(|_| io::Error::last_os_error()) - }; - - // The following code replicates `MoveFileEx`'s behavior as reverse-engineered from its disassembly. - // If `old` refers to a mount point, we move it instead of the target. - let handle = match create_file(c::FILE_READ_ATTRIBUTES, c::FILE_FLAG_OPEN_REPARSE_POINT) { - Ok(handle) => { - let mut file_attribute_tag_info: MaybeUninit<c::FILE_ATTRIBUTE_TAG_INFO> = - MaybeUninit::uninit(); - - let result = unsafe { - cvt(c::GetFileInformationByHandleEx( - handle.as_raw_handle(), - c::FileAttributeTagInfo, - file_attribute_tag_info.as_mut_ptr().cast(), - mem::size_of::<c::FILE_ATTRIBUTE_TAG_INFO>().try_into().unwrap(), - )) + if unsafe { c::MoveFileExW(old.as_ptr(), new.as_ptr(), c::MOVEFILE_REPLACE_EXISTING) } == 0 { + let err = api::get_last_error(); + // if `MoveFileExW` fails with ERROR_ACCESS_DENIED then try to move + // the file while ignoring the readonly attribute. + // This is accomplished by calling `SetFileInformationByHandle` with `FileRenameInfoEx`. + if err == WinError::ACCESS_DENIED { + let mut opts = OpenOptions::new(); + opts.access_mode(c::DELETE); + opts.custom_flags(c::FILE_FLAG_OPEN_REPARSE_POINT | c::FILE_FLAG_BACKUP_SEMANTICS); + let Ok(f) = File::open_native(&old, &opts) else { return Err(err).io_result() }; + + // Calculate the layout of the `FILE_RENAME_INFO` we pass to `SetFileInformation` + // This is a dynamically sized struct so we need to get the position of the last field to calculate the actual size. + let Ok(new_len_without_nul_in_bytes): Result<u32, _> = ((new.len() - 1) * 2).try_into() + else { + return Err(err).io_result(); }; - - if let Err(err) = result { - if err.raw_os_error() == Some(c::ERROR_INVALID_PARAMETER as _) - || err.raw_os_error() == Some(c::ERROR_INVALID_FUNCTION as _) - { - // `GetFileInformationByHandleEx` documents that not all underlying drivers support all file information classes. - // Since we know we passed the correct arguments, this means the underlying driver didn't understand our request; - // `MoveFileEx` proceeds by reopening the file without inhibiting reparse point behavior. - None - } else { - Some(Err(err)) - } - } else { - // SAFETY: The struct has been initialized by GetFileInformationByHandleEx - let file_attribute_tag_info = unsafe { file_attribute_tag_info.assume_init() }; - let file_type = FileType::new( - file_attribute_tag_info.FileAttributes, - file_attribute_tag_info.ReparseTag, - ); - - if file_type.is_symlink() { - // The file is a mount point, junction point or symlink so - // don't reopen the file so that the link gets renamed. - Some(Ok(handle)) - } else { - // Otherwise reopen the file without inhibiting reparse point behavior. - None + let offset: u32 = offset_of!(c::FILE_RENAME_INFO, FileName).try_into().unwrap(); + let struct_size = offset + new_len_without_nul_in_bytes + 2; + let layout = + Layout::from_size_align(struct_size as usize, align_of::<c::FILE_RENAME_INFO>()) + .unwrap(); + + // SAFETY: We allocate enough memory for a full FILE_RENAME_INFO struct and a filename. + let file_rename_info; + unsafe { + file_rename_info = alloc(layout).cast::<c::FILE_RENAME_INFO>(); + if file_rename_info.is_null() { + return Err(io::ErrorKind::OutOfMemory.into()); } - } - } - // The underlying driver may not support `FILE_FLAG_OPEN_REPARSE_POINT`: Retry without it. - Err(err) if err.raw_os_error() == Some(c::ERROR_INVALID_PARAMETER as _) => None, - Err(err) => Some(Err(err)), - } - .unwrap_or_else(|| create_file(0, 0))?; - let layout = core::alloc::Layout::from_size_align( - struct_size as _, - mem::align_of::<c::FILE_RENAME_INFO>(), - ) - .unwrap(); - - let file_rename_info = unsafe { alloc(layout) } as *mut c::FILE_RENAME_INFO; - - if file_rename_info.is_null() { - handle_alloc_error(layout); - } - - // SAFETY: file_rename_info is a non-null pointer pointing to memory allocated by the global allocator. - let mut file_rename_info = unsafe { Box::from_raw(file_rename_info) }; - - // SAFETY: We have allocated enough memory for a full FILE_RENAME_INFO struct and a filename. - unsafe { - (&raw mut (*file_rename_info).Anonymous).write(c::FILE_RENAME_INFO_0 { - Flags: c::FILE_RENAME_FLAG_REPLACE_IF_EXISTS | c::FILE_RENAME_FLAG_POSIX_SEMANTICS, - }); - - (&raw mut (*file_rename_info).RootDirectory).write(ptr::null_mut()); - (&raw mut (*file_rename_info).FileNameLength).write(new_len_without_nul_in_bytes); - - new.as_ptr() - .copy_to_nonoverlapping((&raw mut (*file_rename_info).FileName) as *mut u16, new.len()); - } + (&raw mut (*file_rename_info).Anonymous).write(c::FILE_RENAME_INFO_0 { + Flags: c::FILE_RENAME_FLAG_REPLACE_IF_EXISTS + | c::FILE_RENAME_FLAG_POSIX_SEMANTICS, + }); - // We don't use `set_file_information_by_handle` here as `FILE_RENAME_INFO` is used for both `FileRenameInfo` and `FileRenameInfoEx`. - let result = unsafe { - cvt(c::SetFileInformationByHandle( - handle.as_raw_handle(), - c::FileRenameInfoEx, - (&raw const *file_rename_info).cast::<c_void>(), - struct_size, - )) - }; + (&raw mut (*file_rename_info).RootDirectory).write(ptr::null_mut()); + // Don't include the NULL in the size + (&raw mut (*file_rename_info).FileNameLength).write(new_len_without_nul_in_bytes); - if let Err(err) = result { - if err.raw_os_error() == Some(c::ERROR_INVALID_PARAMETER as _) { - // FileRenameInfoEx and FILE_RENAME_FLAG_POSIX_SEMANTICS were added in Windows 10 1607; retry with FileRenameInfo. - file_rename_info.Anonymous.ReplaceIfExists = 1; + new.as_ptr().copy_to_nonoverlapping( + (&raw mut (*file_rename_info).FileName).cast::<u16>(), + new.len(), + ); + } - cvt(unsafe { + let result = unsafe { c::SetFileInformationByHandle( - handle.as_raw_handle(), - c::FileRenameInfo, - (&raw const *file_rename_info).cast::<c_void>(), + f.as_raw_handle(), + c::FileRenameInfoEx, + file_rename_info.cast::<c_void>(), struct_size, ) - })?; + }; + unsafe { dealloc(file_rename_info.cast::<u8>(), layout) }; + if result == 0 { + if api::get_last_error() == WinError::DIR_NOT_EMPTY { + return Err(WinError::DIR_NOT_EMPTY).io_result(); + } else { + return Err(err).io_result(); + } + } } else { - return Err(err); + return Err(err).io_result(); } } - Ok(()) } |