path: root/src/file.rs

use std::ascii::AsciiExt;
use std::env::current_dir;
use std::fs;
use std::io;
use std::os::unix;
use std::os::unix::raw::mode_t;
use std::os::unix::fs::{MetadataExt, PermissionsExt};
use std::path::{Component, Path, PathBuf};

use ansi_term::{ANSIString, ANSIStrings, Colour, Style};
use ansi_term::Style::Plain;
use ansi_term::Colour::{Red, Green, Yellow, Blue, Purple, Cyan, Fixed};

use users::Users;

use locale;

use unicode_width::UnicodeWidthStr;

use number_prefix::{binary_prefix, decimal_prefix, Prefixed, Standalone, PrefixNames};

use datetime::local::{LocalDateTime, DatePiece};
use datetime::format::{DateFormat};

use colours::Colours;
use column::{Column, Cell};
use column::Column::*;
use dir::Dir;
use filetype::file_colour;
use options::{SizeFormat, TimeType};
use output::details::UserLocale;
use feature::Attribute;

/// This grey value is directly in between white and black, so it's guaranteed
/// to show up on either backgrounded terminal.
pub static GREY: Colour = Fixed(244);

/// A **File** is a wrapper around one of Rust's Path objects, along with
/// associated data about the file.
///
/// Each file is definitely going to have its filename displayed at least
/// once, have its file extension extracted at least once, and have its stat
/// information queried at least once, so it makes sense to do all this at the
/// start and hold on to all the information.
pub struct File<'a> {
    pub name:  String,
    pub dir:   Option<&'a Dir>,
    pub ext:   Option<String>,
    pub path:  PathBuf,
    pub stat:  fs::Metadata,
    pub xattrs: Vec<Attribute>,
    pub this:  Option<Dir>,
}

impl<'a> File<'a> {
    /// Create a new File object from the given Path, inside the given Dir, if
    /// appropriate. Paths specified directly on the command-line have no Dirs.
    ///
    /// This uses `symlink_metadata` instead of `metadata`, which doesn't
    /// follow symbolic links.
    pub fn from_path(path: &Path, parent: Option<&'a Dir>, recurse: bool) -> io::Result<File<'a>> {
        fs::symlink_metadata(path).map(|stat| File::with_stat(stat, path, parent, recurse))
    }

    /// Create a new File object from the given Stat result, and other data.
    pub fn with_stat(stat: fs::Metadata, path: &Path, parent: Option<&'a Dir>, recurse: bool) -> File<'a> {
        let filename = path_filename(path);

        // If we are recursing, then the `this` field contains a Dir object
        // that represents the current File as a directory, if it is a
        // directory. This is used for the --tree option.
        let this = if recurse && stat.is_dir() {
            Dir::readdir(path).ok()
        }
        else {
            None
        };

        File {
            path:   path.to_path_buf(),
            dir:    parent,
            stat:   stat,
            ext:    ext(&filename),
            xattrs: Attribute::llist(path).unwrap_or(Vec::new()),
            name:   filename.to_string(),
            this:   this,
        }
    }

    pub fn is_directory(&self) -> bool {
        self.stat.is_dir()
    }

    pub fn is_file(&self) -> bool {
        self.stat.is_file()
    }

    pub fn is_executable_file(&self) -> bool {
        let bit = unix::fs::USER_EXECUTE;
        self.is_file() && (self.stat.permissions().mode() & bit) == bit
    }

    pub fn is_link(&self) -> bool {
        self.stat.file_type().is_symlink()
    }

    pub fn is_pipe(&self) -> bool {
        false  // TODO: Still waiting on this one...
    }

    /// Whether this file is a dotfile or not.
    pub fn is_dotfile(&self) -> bool {
        self.name.starts_with(".")
    }

    /// Get the data for a column, formatted as a coloured string.
    pub fn display<U: Users>(&self, column: &Column, users_cache: &mut U, locale: &UserLocale) -> Cell {
        match *column {
            Permissions     => self.permissions_string(),
            FileSize(f)     => self.file_size(f, &locale.numeric),
            Timestamp(t, y) => self.timestamp(t, y, &locale.time),
            HardLinks       => self.hard_links(&locale.numeric),
            Inode           => self.inode(),
            Blocks          => self.blocks(&locale.numeric),
            User            => self.user(users_cache),
            Group           => self.group(users_cache),
            GitStatus       => self.git_status(),
        }
    }

    /// The "file name view" is what's displayed in the column and lines
    /// views, but *not* in the grid view.
    ///
    /// It consists of the file name coloured in the appropriate style,
    /// with special formatting for a symlink.
    pub fn file_name_view(&self, colours: &Colours) -> String {
        if self.is_link() {
            self.symlink_file_name_view(colours)
        }
        else {
            file_colour(colours, self).paint(&*self.name).to_string()
        }
    }

    /// If this file is a symlink, returns a string displaying its name,
    /// and an arrow pointing to the file it links to, which is also
    /// coloured in the appropriate style.
    ///
    /// If the symlink target doesn't exist, then instead of displaying
    /// an error, highlight the target and arrow in red. The error would
    /// be shown out of context, and it's almost always because the
    /// target doesn't exist.
    fn symlink_file_name_view(&self, colours: &Colours) -> String {
        let name = &*self.name;
        let style = file_colour(colours, self);

        if let Ok(path) = fs::read_link(&self.path) {
            let target_path = match self.dir {
                Some(dir) => dir.join(&*path),
                None => path,
            };

            match self.target_file(&target_path) {
                Ok(file) => {

                    // Generate a preview for the path this symlink links to.
                    // The preview should consist of the directory of the file
                    // (if present) in cyan, an extra slash if necessary, then
                    // the target file, colourised in the appropriate style.
                    let mut path_prefix = String::new();

                    let path_bytes: Vec<Component> = file.path.components().collect();
                    if !path_bytes.is_empty() {
                        // Use init() to add all but the last component of the
                        // path to the prefix. init() panics when given an
                        // empty list, hence the check.
                        for