[rust] Add XZ uncompressor

Add a XZ uncompressor to uncompress the new Firefox nightly builds for
Linux. This is based on the BZ2 uncompressor.

rust/src/files.rs

@@ -27,6 +27,7 @@ use apple_flat_package::PkgReader;
 use bzip2::read::BzDecoder;
 use directories::BaseDirs;
 use flate2::read::GzDecoder;
+use xz2::read::XzDecoder;
 use regex::Regex;
 use std::fs;
 use std::fs::File;
@@ -49,6 +50,7 @@ const DMG: &str = "dmg";
 const EXE: &str = "exe";
 const DEB: &str = "deb";
 const MSI: &str = "msi";
+const XZ: &str = "xz";
 const SEVEN_ZIP_HEADER: &[u8; 6] = b"7z\xBC\xAF\x27\x1C";
 const UNCOMPRESS_MACOS_ERR_MSG: &str = "{} files are only supported in macOS";
 
@@ -124,6 +126,8 @@ pub fn uncompress(
         untargz(compressed_file, target, log)?
     } else if extension.eq_ignore_ascii_case(BZ2) {
         uncompress_bz2(compressed_file, target, log)?
+    } else if extension.eq_ignore_ascii_case(XZ) {
+        uncompress_xz(compressed_file, target, log)?
     } else if extension.eq_ignore_ascii_case(PKG) {
         uncompress_pkg(compressed_file, target, log)?
     } else if extension.eq_ignore_ascii_case(DMG) {
@@ -339,6 +343,28 @@ pub fn uncompress_bz2(compressed_file: &str, target: &Path, log: &Logger) -> Res
     Ok(())
 }
 
+pub fn uncompress_xz(compressed_file: &str, target: &Path, log: &Logger) -> Result<(), Error> {
+    log.trace(format!(
+        "Uncompress {} to {}",
+        compressed_file,
+        target.display()
+    ));
+    let mut xz_decoder = XzDecoder::new(File::open(compressed_file)?);
+    let mut buffer: Vec<u8> = Vec::new();
+    xz_decoder.read_to_end(&mut buffer)?;
+    let mut archive = Archive::new(Cursor::new(buffer));
+    if !target.exists() {
+        for entry in archive.entries()? {
+            let mut entry_decoder = entry?;
+            let entry_path: PathBuf = entry_decoder.path()?.iter().skip(1).collect();
+            let entry_target = target.join(entry_path);
+            fs::create_dir_all(entry_target.parent().unwrap())?;
+            entry_decoder.unpack(entry_target)?;
+        }
+    }
+    Ok(())
+}
+
 pub fn unzip(
     compressed_file: &str,
     target: &Path,