diff options
| -rw-r--r-- | src/tools/miri/src/shims/windows/foreign_items.rs | 118 | ||||
| -rw-r--r-- | src/tools/miri/tests/pass/path.rs | 25 |
2 files changed, 107 insertions, 36 deletions
diff --git a/src/tools/miri/src/shims/windows/foreign_items.rs b/src/tools/miri/src/shims/windows/foreign_items.rs index 33b65404239..7d97e333cd9 100644 --- a/src/tools/miri/src/shims/windows/foreign_items.rs +++ b/src/tools/miri/src/shims/windows/foreign_items.rs @@ -21,57 +21,107 @@ pub fn is_dyn_sym(name: &str) -> bool { } #[cfg(windows)] -fn win_absolute<'tcx>(path: &Path) -> InterpResult<'tcx, io::Result<PathBuf>> { +fn win_get_full_path_name<'tcx>(path: &Path) -> InterpResult<'tcx, io::Result<PathBuf>> { // We are on Windows so we can simply let the host do this. interp_ok(path::absolute(path)) } #[cfg(unix)] #[expect(clippy::get_first, clippy::arithmetic_side_effects)] -fn win_absolute<'tcx>(path: &Path) -> InterpResult<'tcx, io::Result<PathBuf>> { - // We are on Unix, so we need to implement parts of the logic ourselves. +fn win_get_full_path_name<'tcx>(path: &Path) -> InterpResult<'tcx, io::Result<PathBuf>> { + use std::sync::LazyLock; + + use rustc_data_structures::fx::FxHashSet; + + // We are on Unix, so we need to implement parts of the logic ourselves. `path` will use `/` + // separators, and the result should also use `/`. + // See <https://chrisdenton.github.io/omnipath/Overview.html#absolute-win32-paths> for more + // information about Windows paths. + // This does not handle all corner cases correctly, see + // <https://github.com/rust-lang/miri/pull/4262#issuecomment-2792168853> for more cursed + // examples. let bytes = path.as_os_str().as_encoded_bytes(); - // If it starts with `//` (these were backslashes but are already converted) - // then this is a magic special path, we just leave it unchanged. - if bytes.get(0).copied() == Some(b'/') && bytes.get(1).copied() == Some(b'/') { + // If it starts with `//./` or `//?/` then this is a magic special path, we just leave it + // unchanged. + if bytes.get(0).copied() == Some(b'/') + && bytes.get(1).copied() == Some(b'/') + && matches!(bytes.get(2), Some(b'.' | b'?')) + && bytes.get(3).copied() == Some(b'/') + { return interp_ok(Ok(path.into())); }; - // Special treatment for Windows' magic filenames: they are treated as being relative to `\\.\`. - let magic_filenames = &[ - "CON", "PRN", "AUX", "NUL", "COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", "COM8", - "COM9", "LPT1", "LPT2", "LPT3", "LPT4", "LPT5", "LPT6", "LPT7", "LPT8", "LPT9", - ]; - if magic_filenames.iter().any(|m| m.as_bytes() == bytes) { - let mut result: Vec<u8> = br"//./".into(); + let is_unc = bytes.starts_with(b"//"); + // Special treatment for Windows' magic filenames: they are treated as being relative to `//./`. + static MAGIC_FILENAMES: LazyLock<FxHashSet<&'static str>> = LazyLock::new(|| { + FxHashSet::from_iter([ + "CON", "PRN", "AUX", "NUL", "COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", + "COM8", "COM9", "LPT1", "LPT2", "LPT3", "LPT4", "LPT5", "LPT6", "LPT7", "LPT8", "LPT9", + ]) + }); + if str::from_utf8(bytes).is_ok_and(|s| MAGIC_FILENAMES.contains(&*s.to_ascii_uppercase())) { + let mut result: Vec<u8> = b"//./".into(); result.extend(bytes); return interp_ok(Ok(bytes_to_os_str(&result)?.into())); } // Otherwise we try to do something kind of close to what Windows does, but this is probably not - // right in all cases. We iterate over the components between `/`, and remove trailing `.`, - // except that trailing `..` remain unchanged. - let mut result = vec![]; + // right in all cases. + let mut result: Vec<&[u8]> = vec![]; // will be a vecot of components, joined by `/`. let mut bytes = bytes; // the remaining bytes to process - loop { - let len = bytes.iter().position(|&b| b == b'/').unwrap_or(bytes.len()); - let mut component = &bytes[..len]; - if len >= 2 && component[len - 1] == b'.' && component[len - 2] != b'.' { - // Strip trailing `.` - component = &component[..len - 1]; + let mut stop = false; + while !stop { + // Find next component, and advance `bytes`. + let mut component = match bytes.iter().position(|&b| b == b'/') { + Some(pos) => { + let (component, tail) = bytes.split_at(pos); + bytes = &tail[1..]; // remove the `/`. + component + } + None => { + // There's no more `/`. + stop = true; + let component = bytes; + bytes = &[]; + component + } + }; + // `NUL` and only `NUL` also gets changed to be relative to `//./` later in the path. + // (This changed with Windows 11; previously, all magic filenames behaved like this.) + // Also, this does not apply to UNC paths. + if !is_unc && component.eq_ignore_ascii_case(b"NUL") { + let mut result: Vec<u8> = b"//./".into(); + result.extend(component); + return interp_ok(Ok(bytes_to_os_str(&result)?.into())); } - // Add this component to output. - result.extend(component); - // Prepare next iteration. - if len < bytes.len() { - // There's a component after this; add `/` and process remaining bytes. - result.push(b'/'); - bytes = &bytes[len + 1..]; + // Deal with `..` -- Windows handles this entirely syntactically. + if component == b".." { + // Remove previous component, unless we are at the "root" already, then just ignore the `..`. + let is_root = { + // Paths like `/C:`. + result.len() == 2 && matches!(result[0], []) && matches!(result[1], [_, b':']) + } || { + // Paths like `//server/share` + result.len() == 4 && matches!(result[0], []) && matches!(result[1], []) + }; + if !is_root { + result.pop(); + } continue; - } else { - // This was the last component and it did not have a trailing `/`. - break; } + // Preserve this component. + // Strip trailing `.`, but preserve trailing `..`. But not for UNC paths! + let len = component.len(); + if !is_unc && len >= 2 && component[len - 1] == b'.' && component[len - 2] != b'.' { + component = &component[..len - 1]; + } + // Add this component to output. + result.push(component); + } + // Drive letters must be followed by a `/`. + if result.len() == 2 && matches!(result[0], []) && matches!(result[1], [_, b':']) { + result.push(&[]); } - // Let the host `absolute` function do working-dir handling + // Let the host `absolute` function do working-dir handling. + let result = result.join(&b'/'); interp_ok(path::absolute(bytes_to_os_str(&result)?)) } @@ -226,7 +276,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> { } let filename = this.read_path_from_wide_str(filename)?; - let result = match win_absolute(&filename)? { + let result = match win_get_full_path_name(&filename)? { Err(err) => { this.set_last_error(err)?; Scalar::from_u32(0) // return zero upon failure diff --git a/src/tools/miri/tests/pass/path.rs b/src/tools/miri/tests/pass/path.rs index 299ee6cfe9d..7428d0afcc6 100644 --- a/src/tools/miri/tests/pass/path.rs +++ b/src/tools/miri/tests/pass/path.rs @@ -6,7 +6,11 @@ mod utils; #[track_caller] fn assert_absolute_eq(in_: &str, out: &str) { - assert_eq!(absolute(in_).unwrap().as_os_str(), Path::new(out).as_os_str()); + assert_eq!( + absolute(in_).unwrap().as_os_str(), + Path::new(out).as_os_str(), + "incorrect absolute path for {in_:?}" + ); } fn test_absolute() { @@ -29,11 +33,28 @@ fn test_absolute() { assert_absolute_eq(r"\\?\C:\path\to\file", r"\\?\C:\path\to\file"); assert_absolute_eq(r"\\?\UNC\server\share\to\file", r"\\?\UNC\server\share\to\file"); assert_absolute_eq(r"\\?\PIPE\name", r"\\?\PIPE\name"); + assert_absolute_eq(r"\\server\share\NUL", r"\\server\share\NUL"); + // This fails on Windows 10 hosts. FIXME: enable this once GHA runners are on Windows 11. + //assert_absolute_eq(r"C:\path\to\COM1", r"C:\path\to\COM1"); // Verbatim paths are always unchanged, no matter what. assert_absolute_eq(r"\\?\path.\to/file..", r"\\?\path.\to/file.."); - + // Trailing dot is removed here. assert_absolute_eq(r"C:\path..\to.\file.", r"C:\path..\to\file"); + // `..` is resolved here. + assert_absolute_eq(r"C:\path\to\..\file", r"C:\path\file"); + assert_absolute_eq(r"C:\path\to\..\..\file", r"C:\file"); + assert_absolute_eq(r"C:\path\to\..\..\..\..\..\..\file", r"C:\file"); + assert_absolute_eq(r"C:\..", r"C:\"); + assert_absolute_eq(r"\\server\share\to\path\with\..\file", r"\\server\share\to\path\file"); + assert_absolute_eq(r"\\server\share\to\..\..\..\..\file", r"\\server\share\file"); + assert_absolute_eq(r"\\server\share\..", r"\\server\share"); + // Magic filenames. + assert_absolute_eq(r"NUL", r"\\.\NUL"); + assert_absolute_eq(r"nul", r"\\.\nul"); assert_absolute_eq(r"COM1", r"\\.\COM1"); + assert_absolute_eq(r"com1", r"\\.\com1"); + assert_absolute_eq(r"C:\path\to\NUL", r"\\.\NUL"); + assert_absolute_eq(r"C:\path\to\nul", r"\\.\nul"); } else { panic!("unsupported OS"); } |