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#![cfg(any(doc, all(unix, feature = "std")))]
use std::env;
use std::io;
#[cfg(not(doc))]
use std::os::unix::ffi::OsStrExt;
use std::path::Component;
use std::path::{Path, PathBuf};
pub trait PosixPathExt: Sealed {
/// [Unix only] Make a POSIX path absolute without changing its semantics.
///
/// Unlike canonicalize the path does not need to exist. Symlinks and `..`
/// components will not be resolved.
///
/// # Example
///
/// ```
/// #[cfg(unix)]
/// {
/// use omnipath::posix::PosixPathExt;
/// use std::path::Path;
/// use std::env::current_dir;
///
/// let path = Path::new(r"path/to/..//./file");
/// assert_eq!(
/// path.posix_absolute().unwrap(),
/// current_dir().unwrap().join("path/to/../file")
/// )
/// }
/// ```
fn posix_absolute(&self) -> io::Result<PathBuf>;
/// [Unix only] Make a POSIX path lexically absolute.
///
/// Unlike `canonicalize` the path does not need to exist. Symlinks will not be resolved.
/// Unlike [`posix_absolute`][PosixPathExt::posix_absolute] this resolves `..` components by popping the
/// parent component. This means that it may resolve to a different path
/// than would be resolved by passing the path directly to the OS.
///
/// Usually this is not the preferred behaviour.
///
/// # Example
///
/// ```
/// #[cfg(unix)]
/// {
/// use omnipath::posix::PosixPathExt;
/// use std::path::Path;
/// use std::env::current_dir;
///
/// let path = Path::new(r"path/to/..//./file");
/// assert_eq!(
/// path.posix_lexically_absolute().unwrap(),
/// current_dir().unwrap().join("path/file")
/// )
/// }
/// ```
fn posix_lexically_absolute(&self) -> io::Result<PathBuf>;
/// [Unix only] Make a POSIX path absolute relative to a provided working
/// directory without changing its semantics.
///
/// See [`PosixPathExt::posix_absolute`] for a version of this function that
/// is relative to [`std::env::current_dir()`] instead.
///
/// # Example
///
/// ```
/// #[cfg(unix)]
/// {
/// use omnipath::posix::PosixPathExt;
/// use std::path::Path;
/// let working_dir = Path::new("/tmp");
/// let path = Path::new("path/to/..//./file");
///
/// assert_eq!(
/// &path.posix_absolute_from(working_dir).unwrap(),
/// Path::new("/tmp/path/to/../file"),
/// )
/// }
/// ```
///
/// ```
/// #[cfg(unix)]
/// {
/// use omnipath::posix::PosixPathExt;
/// use std::path::Path;
/// use std::env::current_dir;
/// let root = Path::new("/tmp/foo//.././bar");
/// let path = Path::new(r"path/to/..//./file");
/// assert_eq!(
/// &path.posix_absolute_from(root).unwrap(),
/// Path::new("/tmp/foo/../bar/path/to/../file"),
/// );
/// }
/// ```
fn posix_absolute_from(&self, path: &Path) -> io::Result<PathBuf>;
/// [Unix only] Make a POSIX path lexically absolute relative to a provided
/// current working directory.
///
/// Unlike `canonicalize` the path does not need to exist. Symlinks will not be resolved.
/// Unlike [`posix_absolute`][PosixPathExt::posix_absolute] this resolves `..` components by popping the
/// parent component. This means that it may resolve to a different path
/// than would be resolved by passing the path directly to the OS.
///
/// Usually this is not the preferred behaviour.
///
/// See [`PosixPathExt::posix_lexically_absolute`] for a version of this function that
/// is relative to [`std::env::current_dir()`] instead.
///
/// # Example
///
/// ```
/// #[cfg(unix)]
/// {
/// use omnipath::posix::PosixPathExt;
/// use std::path::Path;
/// use std::env::current_dir;
/// let root = Path::new("/tmp");
/// let path = Path::new(r"path/to/..//./file");
/// assert_eq!(
/// &path.posix_lexically_absolute_from(root).unwrap(),
/// Path::new("/tmp/path/file")
/// );
/// }
/// ```
///
/// ```
/// #[cfg(unix)]
/// {
/// use omnipath::posix::PosixPathExt;
/// use std::path::Path;
/// use std::env::current_dir;
/// let root = Path::new("/tmp/foo//.././bar");
/// let path = Path::new(r"path/to/..//./file");
/// assert_eq!(
/// &path.posix_lexically_absolute_from(root).unwrap(),
/// Path::new("/tmp/bar/path/file")
/// );
/// }
/// ```
fn posix_lexically_absolute_from(&self, cwd: &Path) -> io::Result<PathBuf>;
}
impl PosixPathExt for Path {
fn posix_absolute(&self) -> io::Result<PathBuf> {
posix_absolute_from(self, env::current_dir)
}
fn posix_lexically_absolute(&self) -> io::Result<PathBuf> {
posix_lexically_absolute_from(self, env::current_dir)
}
fn posix_absolute_from(&self, cwd: &Path) -> io::Result<PathBuf> {
if !cwd.is_absolute() {
return Err(cwd_error());
}
posix_absolute_from(self, || posix_absolute_from(cwd, || unreachable!()))
}
fn posix_lexically_absolute_from(&self, cwd: &Path) -> io::Result<PathBuf> {
if !cwd.is_absolute() {
return Err(cwd_error());
}
posix_lexically_absolute_from(self, || {
posix_lexically_absolute_from(cwd, || unreachable!())
})
}
}
fn cwd_error() -> io::Error {
io::Error::new(
io::ErrorKind::InvalidInput,
"expected an absolute path as the current working directory",
)
}
mod private {
pub trait Sealed {}
impl Sealed for std::path::Path {}
}
use private::Sealed;
fn posix_lexically_absolute_from<F>(path: &Path, get_cwd: F) -> io::Result<PathBuf>
where
F: FnOnce() -> io::Result<PathBuf>,
{
// This is mostly a wrapper around collecting `Path::components`, with
// exceptions made where this conflicts with the POSIX specification.
// See 4.13 Pathname Resolution, IEEE Std 1003.1-2017
// https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13
// Get the components, skipping the redundant leading "." component if it exists.
let mut components = path.strip_prefix(".").unwrap_or(path).components();
let path_os = path.as_os_str().as_bytes();
let mut normalized = if path.is_absolute() {
// "If a pathname begins with two successive <slash> characters, the
// first component following the leading <slash> characters may be
// interpreted in an implementation-defined manner, although more than
// two leading <slash> characters shall be treated as a single <slash>
// character."
if path_os.starts_with(b"//") && !path_os.starts_with(b"///") {
components.next();
PathBuf::from("//")
} else {
PathBuf::new()
}
} else {
get_cwd()?
};
components.for_each(|component| {
if component == Component::ParentDir {
normalized.pop();
} else {
normalized.push(component);
}
});
// "Interfaces using pathname resolution may specify additional constraints
// when a pathname that does not name an existing directory contains at
// least one non- <slash> character and contains one or more trailing
// <slash> characters".
// A trailing <slash> is also meaningful if "a symbolic link is
// encountered during pathname resolution".
if path_os.ends_with(b"/") {
normalized.push("");
}
Ok(normalized)
}
fn posix_absolute_from<F>(path: &Path, get_cwd: F) -> io::Result<PathBuf>
where
F: FnOnce() -> io::Result<PathBuf>,
{
// This is mostly a wrapper around collecting `Path::components`, with
// exceptions made where this conflicts with the POSIX specification.
// See 4.13 Pathname Resolution, IEEE Std 1003.1-2017
// https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13
// Get the components, skipping the redundant leading "." component if it exists.
let mut components = path.strip_prefix(".").unwrap_or(path).components();
let path_os = path.as_os_str().as_bytes();
let mut normalized = if path.is_absolute() {
// "If a pathname begins with two successive <slash> characters, the
// first component following the leading <slash> characters may be
// interpreted in an implementation-defined manner, although more than
// two leading <slash> characters shall be treated as a single <slash>
// character."
if path_os.starts_with(b"//") && !path_os.starts_with(b"///") {
components.next();
PathBuf::from("//")
} else {
PathBuf::new()
}
} else {
get_cwd()?
};
normalized.extend(components);
// "Interfaces using pathname resolution may specify additional constraints
// when a pathname that does not name an existing directory contains at
// least one non- <slash> character and contains one or more trailing
// <slash> characters".
// A trailing <slash> is also meaningful if "a symbolic link is
// encountered during pathname resolution".
if path_os.ends_with(b"/") {
normalized.push("");
}
Ok(normalized)
}