2 files changed, 468 insertions, 0 deletions
diff --git a/third_party/rust/dirs-sys/src/lib.rs b/third_party/rust/dirs-sys/src/lib.rs
new file mode 100644
index 0000000000..4f9d67e760
--- /dev/null
+++ b/third_party/rust/dirs-sys/src/lib.rs
@@ -0,0 +1,216 @@
+use std::ffi::OsString;
+use std::path::PathBuf;
+
+// we don't need to explicitly handle empty strings in the code above,
+// because an empty string is not considered to be a absolute path here.
+pub fn is_absolute_path(path: OsString) -> Option<PathBuf> {
+    let path = PathBuf::from(path);
+    if path.is_absolute() {
+        Some(path)
+    } else {
+        None
+    }
+}
+
+#[cfg(all(unix, not(target_os = "redox")))]
+extern crate libc;
+
+#[cfg(all(unix, not(target_os = "redox")))]
+mod target_unix_not_redox {
+
+use std::env;
+use std::ffi::{CStr, OsString};
+use std::mem;
+use std::os::unix::ffi::OsStringExt;
+use std::path::PathBuf;
+use std::ptr;
+
+use super::libc;
+
+// https://github.com/rust-lang/rust/blob/master/src/libstd/sys/unix/os.rs#L498
+pub fn home_dir() -> Option<PathBuf> {
+    return env::var_os("HOME")
+        .and_then(|h| if h.is_empty() { None } else { Some(h) })
+        .or_else(|| unsafe { fallback() })
+        .map(PathBuf::from);
+
+    #[cfg(any(target_os = "android", target_os = "ios", target_os = "emscripten"))]
+    unsafe fn fallback() -> Option<OsString> {
+        None
+    }
+    #[cfg(not(any(target_os = "android", target_os = "ios", target_os = "emscripten")))]
+    unsafe fn fallback() -> Option<OsString> {
+        let amt = match libc::sysconf(libc::_SC_GETPW_R_SIZE_MAX) {
+            n if n < 0 => 512 as usize,
+            n => n as usize,
+        };
+        let mut buf = Vec::with_capacity(amt);
+        let mut passwd: libc::passwd = mem::zeroed();
+        let mut result = ptr::null_mut();
+        match libc::getpwuid_r(
+            libc::getuid(),
+            &mut passwd,
+            buf.as_mut_ptr(),
+            buf.capacity(),
+            &mut result,
+        ) {
+            0 if !result.is_null() => {
+                let ptr = passwd.pw_dir as *const _;
+                let bytes = CStr::from_ptr(ptr).to_bytes();
+                if bytes.is_empty() {
+                    None
+                } else {
+                    Some(OsStringExt::from_vec(bytes.to_vec()))
+                }
+            }
+            _ => None,
+        }
+    }
+}
+
+}
+
+#[cfg(all(unix, not(target_os = "redox")))]
+pub use self::target_unix_not_redox::home_dir;
+
+#[cfg(target_os = "redox")]
+extern crate redox_users;
+
+#[cfg(target_os = "redox")]
+mod target_redox {
+
+use std::path::PathBuf;
+
+use super::redox_users::{All, AllUsers, Config};
+
+pub fn home_dir() -> Option<PathBuf> {
+    let current_uid = redox_users::get_uid().ok()?;
+    let users = AllUsers::basic(Config::default()).ok()?;
+    let user = users.get_by_id(current_uid)?;
+
+    Some(PathBuf::from(user.home.clone()))
+}
+
+}
+
+#[cfg(target_os = "redox")]
+pub use self::target_redox::home_dir;
+
+#[cfg(all(unix, not(any(target_os = "macos", target_os = "ios"))))]
+mod xdg_user_dirs;
+
+#[cfg(all(unix, not(any(target_os = "macos", target_os = "ios"))))]
+mod target_unix_not_mac {
+
+use std::collections::HashMap;
+use std::env;
+use std::path::{Path, PathBuf};
+
+use super::{home_dir, is_absolute_path};
+use super::xdg_user_dirs;
+
+fn user_dir_file(home_dir: &Path) -> PathBuf {
+    env::var_os("XDG_CONFIG_HOME").and_then(is_absolute_path).unwrap_or_else(|| home_dir.join(".config")).join("user-dirs.dirs")
+}
+
+// this could be optimized further to not create a map and instead retrieve the requested path only
+pub fn user_dir(user_dir_name: &str) -> Option<PathBuf> {
+    if let Some(home_dir) = home_dir() {
+        xdg_user_dirs::single(&home_dir, &user_dir_file(&home_dir), user_dir_name).remove(user_dir_name)
+    } else {
+        None
+    }
+}
+
+pub fn user_dirs(home_dir_path: &Path) -> HashMap<String, PathBuf> {
+    xdg_user_dirs::all(home_dir_path, &user_dir_file(home_dir_path))
+}
+
+}
+
+#[cfg(all(unix, not(any(target_os = "macos", target_os = "ios"))))]
+pub use self::target_unix_not_mac::{user_dir, user_dirs};
+
+#[cfg(target_os = "windows")]
+extern crate winapi;
+
+#[cfg(target_os = "windows")]
+mod target_windows {
+
+use std::ffi::OsString;
+use std::os::windows::ffi::OsStringExt;
+use std::path::PathBuf;
+use std::ptr;
+use std::slice;
+
+use super::winapi;
+use super::winapi::shared::winerror;
+use super::winapi::um::{combaseapi, knownfolders, shlobj, shtypes, winbase, winnt};
+
+pub fn known_folder(folder_id: shtypes::REFKNOWNFOLDERID) -> Option<PathBuf> {
+    unsafe {
+        let mut path_ptr: winnt::PWSTR = ptr::null_mut();
+        let result = shlobj::SHGetKnownFolderPath(folder_id, 0, ptr::null_mut(), &mut path_ptr);
+        if result == winerror::S_OK {
+            let len = winbase::lstrlenW(path_ptr) as usize;
+            let path = slice::from_raw_parts(path_ptr, len);
+            let ostr: OsString = OsStringExt::from_wide(path);
+            combaseapi::CoTaskMemFree(path_ptr as *mut winapi::ctypes::c_void);
+            Some(PathBuf::from(ostr))
+        } else {
+            combaseapi::CoTaskMemFree(path_ptr as *mut winapi::ctypes::c_void);
+            None
+        }
+    }
+}
+
+pub fn known_folder_profile() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_Profile)
+}
+
+pub fn known_folder_roaming_app_data() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_RoamingAppData)
+}
+
+pub fn known_folder_local_app_data() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_LocalAppData)
+}
+
+pub fn known_folder_music() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_Music)
+}
+
+pub fn known_folder_desktop() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_Desktop)
+}
+
+pub fn known_folder_documents() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_Documents)
+}
+
+pub fn known_folder_downloads() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_Downloads)
+}
+
+pub fn known_folder_pictures() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_Pictures)
+}
+
+pub fn known_folder_public() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_Public)
+}
+pub fn known_folder_templates() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_Templates)
+}
+pub fn known_folder_videos() -> Option<PathBuf> {
+    known_folder(&knownfolders::FOLDERID_Videos)
+}
+
+}
+
+#[cfg(target_os = "windows")]
+pub use self::target_windows::{
+    known_folder, known_folder_profile, known_folder_roaming_app_data, known_folder_local_app_data,
+    known_folder_music, known_folder_desktop, known_folder_documents, known_folder_downloads,
+    known_folder_pictures, known_folder_public, known_folder_templates, known_folder_videos
+};
diff --git a/third_party/rust/dirs-sys/src/xdg_user_dirs.rs b/third_party/rust/dirs-sys/src/xdg_user_dirs.rs
new file mode 100644
index 0000000000..de7e9e9d20
--- /dev/null
+++ b/third_party/rust/dirs-sys/src/xdg_user_dirs.rs
@@ -0,0 +1,252 @@
+use std::collections::HashMap;
+use std::ffi::OsString;
+use std::fs;
+use std::io::{self, Read};
+use std::os::unix::ffi::OsStringExt;
+use std::path::{Path, PathBuf};
+use std::str;
+
+/// Returns all XDG user directories obtained from $(XDG_CONFIG_HOME)/user-dirs.dirs.
+pub fn all(home_dir_path: &Path, user_dir_file_path: &Path) -> HashMap<String, PathBuf> {
+    let bytes = read_all(user_dir_file_path).unwrap_or(Vec::new());
+    parse_user_dirs(home_dir_path, None, &bytes)
+}
+
+/// Returns a single XDG user directory obtained from $(XDG_CONFIG_HOME)/user-dirs.dirs.
+pub fn single(home_dir_path: &Path, user_dir_file_path: &Path, user_dir_name: &str) -> HashMap<String, PathBuf> {
+    let bytes = read_all(user_dir_file_path).unwrap_or(Vec::new());
+    parse_user_dirs(home_dir_path, Some(user_dir_name), &bytes)
+}
+
+fn parse_user_dirs(home_dir: &Path, user_dir: Option<&str>, bytes: &[u8]) -> HashMap<String, PathBuf> {
+    let mut user_dirs = HashMap::new();
+
+    for line in bytes.split(|b| *b == b'\n') {
+        let mut single_dir_found = false;
+        let (key, value) = match split_once(line, b'=') {
+            Some(kv) => kv,
+            None => continue,
+        };
+
+        let key = trim_blank(key);
+        let key = if key.starts_with(b"XDG_") && key.ends_with(b"_DIR") {
+            match str::from_utf8(&key[4..key.len()-4]) {
+                Ok(key) =>
+                    if user_dir.is_some() && option_contains(user_dir, key) {
+                        single_dir_found = true;
+                        key
+                    } else if user_dir.is_none() {
+                        key
+                    } else {
+                        continue
+                    },
+                Err(_)  => continue,
+            }
+        } else {
+            continue
+        };
+
+        // xdg-user-dirs-update uses double quotes and we don't support anything else.
+        let value = trim_blank(value);
+        let mut value = if value.starts_with(b"\"") && value.ends_with(b"\"") {
+            &value[1..value.len()-1]
+        } else {
+            continue
+        };
+
+        // Path should be either relative to the home directory or absolute.
+        let is_relative = if value == b"$HOME/" {
+            // "Note: To disable a directory, point it to the homedir."
+            // Source: https://www.freedesktop.org/wiki/Software/xdg-user-dirs/
+            // Additionally directory is reassigned to homedir when removed.
+            continue
+        } else if value.starts_with(b"$HOME/") {
+            value = &value[b"$HOME/".len()..];
+            true
+        } else if value.starts_with(b"/") {
+            false
+        } else {
+            continue
+        };
+
+        let value = OsString::from_vec(shell_unescape(value));
+
+        let path = if is_relative {
+            let mut path = PathBuf::from(&home_dir);
+            path.push(value);
+            path
+        } else {
+            PathBuf::from(value)
+        };
+
+        user_dirs.insert(key.to_owned(), path);
+        if single_dir_found {
+            break;
+        }
+    }
+
+    user_dirs
+}
+
+/// Reads the entire contents of a file into a byte vector.
+fn read_all(path: &Path) -> io::Result<Vec<u8>> {
+    let mut file = fs::File::open(path)?;
+    let mut bytes = Vec::with_capacity(1024);
+    file.read_to_end(&mut bytes)?;
+    Ok(bytes)
+}
+
+/// Returns bytes before and after first occurrence of separator.
+fn split_once(bytes: &[u8], separator: u8) -> Option<(&[u8], &[u8])> {
+    bytes.iter().position(|b| *b == separator).map(|i| {
+        (&bytes[..i], &bytes[i+1..])
+    })
+}
+
+/// Returns a slice with leading and trailing <blank> characters removed.
+fn trim_blank(bytes: &[u8]) -> &[u8] {
+    // Trim leading <blank> characters.
+    let i = bytes.iter().cloned().take_while(|b| *b == b' ' || *b == b'\t').count();
+    let bytes = &bytes[i..];
+
+    // Trim trailing <blank> characters.
+    let i = bytes.iter().cloned().rev().take_while(|b| *b == b' ' || *b == b'\t').count();
+    &bytes[..bytes.len()-i]
+}
+
+/// Unescape bytes escaped with POSIX shell double-quotes rules (as used by xdg-user-dirs-update).
+fn shell_unescape(escaped: &[u8]) -> Vec<u8> {
+    // We assume that byte string was created by xdg-user-dirs-update which
+    // escapes all characters that might potentially have special meaning,
+    // so there is no need to check if backslash is actually followed by
+    // $ ` " \ or a <newline>.
+
+    let mut unescaped: Vec<u8> = Vec::with_capacity(escaped.len());
+    let mut i = escaped.iter().cloned();
+
+    while let Some(b) = i.next() {
+        if b == b'\\' {
+            if let Some(b) = i.next() {
+                unescaped.push(b);
+            }
+        } else {
+            unescaped.push(b);
+        }
+    }
+
+    unescaped
+}
+
+fn option_contains<T : PartialEq>(option: Option<T>, value: T) -> bool {
+    match option {
+        Some(val) => val == value,
+        None => false
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::collections::HashMap;
+    use std::path::{Path, PathBuf};
+    use super::{trim_blank, shell_unescape, split_once, parse_user_dirs};
+
+    #[test]
+    fn test_trim_blank() {
+        assert_eq!(b"x", trim_blank(b"x"));
+        assert_eq!(b"", trim_blank(b" \t  "));
+        assert_eq!(b"hello there", trim_blank(b" \t hello there \t "));
+        assert_eq!(b"\r\n", trim_blank(b"\r\n"));
+    }
+
+    #[test]
+    fn test_split_once() {
+        assert_eq!(None, split_once(b"a b c", b'='));
+        assert_eq!(Some((b"before".as_ref(), b"after".as_ref())), split_once(b"before=after", b'='));
+    }
+
+    #[test]
+    fn test_shell_unescape() {
+        assert_eq!(b"abc", shell_unescape(b"abc").as_slice());
+        assert_eq!(b"x\\y$z`", shell_unescape(b"x\\\\y\\$z\\`").as_slice());
+    }
+
+    #[test]
+    fn test_parse_empty() {
+        assert_eq!(HashMap::new(), parse_user_dirs(Path::new("/root/"), None, b""));
+        assert_eq!(HashMap::new(), parse_user_dirs(Path::new("/root/"), Some("MUSIC"), b""));
+    }
+
+    #[test]
+    fn test_absolute_path_is_accepted() {
+        let mut dirs = HashMap::new();
+        dirs.insert("MUSIC".to_owned(), PathBuf::from("/media/music"));
+        let bytes = br#"XDG_MUSIC_DIR="/media/music""#;
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/john"), None, bytes));
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/john"), Some("MUSIC"), bytes));
+    }
+
+    #[test]
+    fn test_relative_path_is_rejected() {
+        let dirs = HashMap::new();
+        let bytes = br#"XDG_MUSIC_DIR="music""#;
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/john"), None, bytes));
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/john"), Some("MUSIC"), bytes));
+    }
+
+    #[test]
+    fn test_relative_to_home() {
+        let mut dirs = HashMap::new();
+        dirs.insert("MUSIC".to_owned(), PathBuf::from("/home/john/Music"));
+        let bytes = br#"XDG_MUSIC_DIR="$HOME/Music""#;
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/john"), None, bytes));
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/john"), Some("MUSIC"), bytes));
+    }
+
+    #[test]
+    fn test_disabled_directory() {
+        let dirs = HashMap::new();
+        let bytes = br#"XDG_MUSIC_DIR="$HOME/""#;
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/john"), None, bytes));
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/john"), Some("MUSIC"), bytes));
+    }
+
+    #[test]
+    fn test_parse_user_dirs() {
+        let mut dirs: HashMap<String, PathBuf> = HashMap::new();
+        dirs.insert("DESKTOP".to_string(), PathBuf::from("/home/bob/Desktop"));
+        dirs.insert("DOWNLOAD".to_string(), PathBuf::from("/home/bob/Downloads"));
+        dirs.insert("PICTURES".to_string(), PathBuf::from("/home/eve/pics"));
+
+        let bytes = br#"
+# This file is written by xdg-user-dirs-update
+# If you want to change or add directories, just edit the line you're
+# interested in. All local changes will be retained on the next run.
+# Format is XDG_xxx_DIR="$HOME/yyy", where yyy is a shell-escaped
+# homedir-relative path, or XDG_xxx_DIR="/yyy", where /yyy is an
+# absolute path. No other format is supported.
+XDG_DESKTOP_DIR="$HOME/Desktop"
+XDG_DOWNLOAD_DIR="$HOME/Downloads"
+XDG_TEMPLATES_DIR=""
+XDG_PUBLICSHARE_DIR="$HOME"
+XDG_DOCUMENTS_DIR="$HOME/"
+XDG_PICTURES_DIR="/home/eve/pics"
+XDG_VIDEOS_DIR="$HOxyzME/Videos"
+"#;
+
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/bob"), None, bytes));
+
+        let mut dirs: HashMap<String, PathBuf> = HashMap::new();
+        dirs.insert("DESKTOP".to_string(), PathBuf::from("/home/bob/Desktop"));
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/bob"), Some("DESKTOP"), bytes));
+
+        let mut dirs: HashMap<String, PathBuf> = HashMap::new();
+        dirs.insert("PICTURES".to_string(), PathBuf::from("/home/eve/pics"));
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/bob"), Some("PICTURES"), bytes));
+
+        let dirs: HashMap<String, PathBuf> = HashMap::new();
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/bob"), Some("TEMPLATES"), bytes));
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/bob"), Some("PUBLICSHARE"), bytes));
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/bob"), Some("DOCUMENTS"), bytes));
+        assert_eq!(dirs, parse_user_dirs(Path::new("/home/bob"), Some("VIDEOS"), bytes));
+    }
+}