sgx_tstd/src/untrusted/path.rs

// Copyright (C) 2017-2018 Baidu, Inc. All Rights Reserved.
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use untrusted::fs;
use io;
use path::Path;
use path::PathBuf;

pub trait PathEx {
    fn metadata(&self) -> io::Result<fs::Metadata>;
    fn symlink_metadata(&self) -> io::Result<fs::Metadata>; 
    fn canonicalize(&self) -> io::Result<PathBuf>;
    fn read_link(&self) -> io::Result<PathBuf>;
    fn exists(&self) -> bool;
    fn is_file(&self) -> bool;
    fn is_dir(&self) -> bool;
}

impl PathEx for Path { 
    /// Queries the file system to get information about a file, directory, etc.
    ///
    /// This function will traverse symbolic links to query information about the
    /// destination file.
    ///
    /// This is an alias to [`fs::metadata`].
    ///
    /// [`fs::metadata`]: ../fs/fn.metadata.html
    ///
    fn metadata(&self) -> io::Result<fs::Metadata> {
        fs::metadata(self)
    }

    /// Queries the metadata about a file without following symlinks.
    ///
    /// This is an alias to [`fs::symlink_metadata`].
    ///
    /// [`fs::symlink_metadata`]: ../fs/fn.symlink_metadata.html
    ///
    fn symlink_metadata(&self) -> io::Result<fs::Metadata> {
        fs::symlink_metadata(self)
    }

    /// Returns the canonical form of the path with all intermediate components
    /// normalized and symbolic links resolved.
    ///
    /// This is an alias to [`fs::canonicalize`].
    ///
    /// [`fs::canonicalize`]: ../fs/fn.canonicalize.html
    ///
    fn canonicalize(&self) -> io::Result<PathBuf> {
        fs::canonicalize(self)
    }

    /// Reads a symbolic link, returning the file that the link points to.
    ///
    /// This is an alias to [`fs::read_link`].
    ///
    /// [`fs::read_link`]: ../fs/fn.read_link.html
    ///
    fn read_link(&self) -> io::Result<PathBuf> {
        fs::read_link(self)
    }

    /// Returns whether the path points at an existing entity.
    ///
    /// This function will traverse symbolic links to query information about the
    /// destination file. In case of broken symbolic links this will return `false`.
    ///
    /// If you cannot access the directory containing the file, e.g. because of a
    /// permission error, this will return `false`.
    ///
    fn exists(&self) -> bool {
        fs::metadata(self).is_ok()
    }

    /// Returns whether the path exists on disk and is pointing at a regular file.
    ///
    /// This function will traverse symbolic links to query information about the
    /// destination file. In case of broken symbolic links this will return `false`.
    ///
    /// If you cannot access the directory containing the file, e.g. because of a
    /// permission error, this will return `false`.
    ///
    fn is_file(&self) -> bool {
        fs::metadata(self).map(|m| m.is_file()).unwrap_or(false)
    }

    /// Returns whether the path exists on disk and is pointing at a directory.
    ///
    /// This function will traverse symbolic links to query information about the
    /// destination file. In case of broken symbolic links this will return `false`.
    ///
    /// If you cannot access the directory containing the file, e.g. because of a
    /// permission error, this will return `false`.
    ///
    fn is_dir(&self) -> bool {
        fs::metadata(self).map(|m| m.is_dir()).unwrap_or(false)
    }
}