Reduce duplicated code

Take shared code between copy_local_input and copy_remote_input into
helper functions.

Signed-off-by: Rafael Garcia Ruiz <rafael.garcia@collabora.com>

bmap-rs/src/main.rs

@@ -163,6 +163,23 @@ async fn setup_remote_input(url: Url) -> Result<Response> {
     reqwest::get(url).await.map_err(anyhow::Error::new)
 }
 
+fn setup_progress_bar(bmap: &Bmap) -> Result<ProgressBar> {
+    let pb = ProgressBar::new(bmap.total_mapped_size());
+    pb.set_style(ProgressStyle::with_template("{spinner:.green} [{elapsed_precise}] [{wide_bar:.cyan/blue}] {bytes}/{total_bytes} ({eta})")
+        .unwrap()
+        .with_key("eta", |state: &ProgressState, w: &mut dyn Write| write!(w, "{:.1}s", state.eta().as_secs_f64()).unwrap())
+        .progress_chars("#>-"));
+    Ok(pb)
+}
+
+fn setup_output<T: AsRawFd>(output: &T, bmap: &Bmap, metadata: std::fs::Metadata) -> Result<()> {
+    if metadata.is_file() {
+        ftruncate(output.as_raw_fd(), bmap.image_size() as i64)
+            .context("Failed to truncate file")?;
+    }
+    Ok(())
+}
+
 async fn copy(c: Copy) -> Result<()> {
     match c.image {
         Image::Path(_) => copy_local_input(c),
@@ -188,17 +205,10 @@ fn copy_local_input(c: Copy) -> Result<()> {
         .create(true)
         .open(c.dest)?;
 
-    if output.metadata()?.is_file() {
-        ftruncate(output.as_raw_fd(), bmap.image_size() as i64)
-            .context("Failed to truncate file")?;
-    }
+    setup_output(&output, &bmap, output.metadata()?)?;
 
     let mut input = setup_local_input(&path)?;
-    let pb = ProgressBar::new(bmap.total_mapped_size());
-    pb.set_style(ProgressStyle::with_template("{spinner:.green} [{elapsed_precise}] [{wide_bar:.cyan/blue}] {bytes}/{total_bytes} ({eta})")
-        .unwrap()
-        .with_key("eta", |state: &ProgressState, w: &mut dyn Write| write!(w, "{:.1}s", state.eta().as_secs_f64()).unwrap())
-        .progress_chars("#>-"));
+    let pb = setup_progress_bar(&bmap)?;
     bmap::copy(&mut input, &mut pb.wrap_write(&output), &bmap)?;
     pb.finish_and_clear();
 
@@ -222,10 +232,7 @@ async fn copy_remote_input(c: Copy) -> Result<()> {
         .open(c.dest)
         .await?;
 
-    if output.metadata().await?.is_file() {
-        ftruncate(output.as_raw_fd(), bmap.image_size() as i64)
-            .context("Failed to truncate file")?;
-    }
+    setup_output(&output, &bmap, output.metadata().await?)?;
 
     let res = setup_remote_input(url).await?;
     let stream = res
@@ -234,11 +241,7 @@ async fn copy_remote_input(c: Copy) -> Result<()> {
         .into_async_read();
     let reader = async_compression::futures::bufread::GzipDecoder::new(stream);
     let mut input = AsyncDiscarder::new(reader);
-    let pb = ProgressBar::new(bmap.total_mapped_size());
-    pb.set_style(ProgressStyle::with_template("{spinner:.green} [{elapsed_precise}] [{wide_bar:.cyan/blue}] {bytes}/{total_bytes} ({eta})")
-        .unwrap()
-        .with_key("eta", |state: &ProgressState, w: &mut dyn Write| write!(w, "{:.1}s", state.eta().as_secs_f64()).unwrap())
-        .progress_chars("#>-"));
+    let pb = setup_progress_bar(&bmap)?;
     bmap::copy_async(
         &mut input,
         &mut pb.wrap_async_write(&mut output).compat(),