Use untar in extract_compressed_from_readable

So that we can specify the files we want to extract to avoid io and save
disk usage.

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

src/helpers.rs

@@ -1,4 +1,5 @@
 use std::{
+    borrow::Cow,
     fs,
     io::{stderr, stdin, Write},
     path::{Path, PathBuf},
@@ -53,14 +54,19 @@ pub async fn remote_exists(url: Url, method: Method) -> Result<bool, BinstallErr
 /// Download a file from the provided URL to the provided path
 pub async fn download<P: AsRef<Path>>(url: &str, path: P) -> Result<(), BinstallError> {
     let url = Url::parse(url)?;
-    download_and_extract(url, PkgFmt::Bin, path.as_ref()).await
+    download_and_extract::<_, 0>(url, PkgFmt::Bin, path.as_ref(), None).await
 }
 
 /// Download a file from the provided URL and extract it to the provided path
-pub async fn download_and_extract<P: AsRef<Path>>(
+///
+///  * `desired_outputs - If Some(_) and `fmt` is not `PkgFmt::Bin` or
+///    `PkgFmt::Zip`, then it will filter the tar and only extract files
+///    specified in it.
+pub async fn download_and_extract<P: AsRef<Path>, const N: usize>(
     url: Url,
     fmt: PkgFmt,
     path: P,
+    desired_outputs: Option<[Cow<'static, Path>; N]>,
 ) -> Result<(), BinstallError> {
     debug!("Downloading from: '{url}'");
 
@@ -77,7 +83,7 @@ pub async fn download_and_extract<P: AsRef<Path>>(
     debug!("Downloading to file: '{}'", path.display());
 
     let mut bytes_stream = resp.bytes_stream();
-    let mut writer = AsyncFileWriter::new(path, fmt);
+    let mut writer = AsyncFileWriter::new(path, fmt, desired_outputs);
 
     while let Some(res) = bytes_stream.next().await {
         writer.write(res?).await?;

src/helpers/async_file_writer.rs

@@ -1,3 +1,4 @@
+use std::borrow::Cow;
 use std::fs;
 use std::io::{self, Seek, Write};
 use std::path::Path;
@@ -27,7 +28,13 @@ struct AsyncFileWriterInner {
 }
 
 impl AsyncFileWriterInner {
-    fn new(path: &Path, fmt: PkgFmt) -> Self {
+    ///  * `desired_outputs - If Some(_), then it will filter the tar
+    ///    and only extract files specified in it.
+    fn new<const N: usize>(
+        path: &Path,
+        fmt: PkgFmt,
+        desired_outputs: Option<[Cow<'static, Path>; N]>,
+    ) -> Self {
         let path = path.to_owned();
         let (tx, rx) = mpsc::channel::<Content>(100);
 
@@ -65,7 +72,12 @@ impl AsyncFileWriterInner {
 
                     unzip(file, &path)?;
                 }
-                _ => extract_compressed_from_readable(ReadableRx::new(&mut rx), fmt, &path)?,
+                _ => extract_compressed_from_readable(
+                    ReadableRx::new(&mut rx),
+                    fmt,
+                    &path,
+                    desired_outputs.as_ref().map(|arr| &arr[..]),
+                )?,
             }
 
             Ok(())
@@ -141,8 +153,15 @@ impl AsyncFileWriterInner {
 pub struct AsyncFileWriter(ScopeGuard<AsyncFileWriterInner, fn(AsyncFileWriterInner), Always>);
 
 impl AsyncFileWriter {
-    pub fn new(path: &Path, fmt: PkgFmt) -> Self {
-        let inner = AsyncFileWriterInner::new(path, fmt);
+    ///  * `desired_outputs - If Some(_) and `fmt` is not `PkgFmt::Bin` or
+    ///    `PkgFmt::Zip`, then it will filter the tar and only extract files
+    ///    specified in it.
+    pub fn new<const N: usize>(
+        path: &Path,
+        fmt: PkgFmt,
+        desired_outputs: Option<[Cow<'static, Path>; N]>,
+    ) -> Self {
+        let inner = AsyncFileWriterInner::new(path, fmt, desired_outputs);
         Self(guard(inner, AsyncFileWriterInner::abort))
     }
 

src/helpers/extracter.rs

@@ -12,6 +12,8 @@ use zstd::stream::Decoder as ZstdDecoder;
 
 use crate::{BinstallError, PkgFmt};
 
+///  * `desired_outputs - If Some(_), then it will filter the tar
+///    and only extract files specified in it.
 fn untar(
     dat: impl Read,
     path: &Path,
@@ -40,37 +42,34 @@ fn untar(
 /// Extract files from the specified source onto the specified path.
 ///
 ///  * `fmt` - must not be `PkgFmt::Bin` or `PkgFmt::Zip`.
+///  * `desired_outputs - If Some(_), then it will filter the tar
+///    and only extract files specified in it.
 pub(crate) fn extract_compressed_from_readable(
     dat: impl Read,
     fmt: PkgFmt,
     path: &Path,
+    desired_outputs: Option<&[Cow<'_, Path>]>,
 ) -> Result<(), BinstallError> {
     match fmt {
         PkgFmt::Tar => {
             // Extract to install dir
             debug!("Extracting from tar archive to `{path:?}`");
 
-            let mut tar = Archive::new(dat);
-
-            tar.unpack(path)?;
+            untar(dat, path, desired_outputs)?
         }
         PkgFmt::Tgz => {
             // Extract to install dir
             debug!("Decompressing from tgz archive to `{path:?}`");
 
             let tar = GzDecoder::new(dat);
-            let mut tgz = Archive::new(tar);
-
-            tgz.unpack(path)?;
+            untar(tar, path, desired_outputs)?;
         }
         PkgFmt::Txz => {
             // Extract to install dir
             debug!("Decompressing from txz archive to `{path:?}`");
 
             let tar = XzDecoder::new(dat);
-            let mut txz = Archive::new(tar);
-
-            txz.unpack(path)?;
+            untar(tar, path, desired_outputs)?;
         }
         PkgFmt::Tzstd => {
             // Extract to install dir
@@ -81,9 +80,7 @@ pub(crate) fn extract_compressed_from_readable(
             // as &[] by ZstdDecoder::new, thus ZstdDecoder::new
             // should not return any error.
             let tar = ZstdDecoder::new(dat)?;
-            let mut txz = Archive::new(tar);
-
-            txz.unpack(path)?;
+            untar(tar, path, desired_outputs)?;
         }
         PkgFmt::Zip => panic!("Unexpected PkgFmt::Zip!"),
         PkgFmt::Bin => panic!("Unexpected PkgFmt::Bin!"),