Can decompress raw files to sparse file

virtweb_backend/src/constants.rs

@@ -129,3 +129,9 @@ pub const COPY_PROGRAM: &str = "/bin/cp";
 
 /// Gzip program path
 pub const GZIP_PROGRAM: &str = "/usr/bin/gzip";
+
+/// Bash program
+pub const BASH_PROGRAM: &str = "/usr/bin/bash";
+
+/// DD program
+pub const DD_PROGRAM: &str = "/usr/bin/dd";

virtweb_backend/src/utils/file_disks_utils.rs

@@ -251,6 +251,20 @@ impl DiskFileInfo {
                 cmd
             }
 
+            // Decompress Raw to sparse file
+            // https://benou.fr/www/ben/decompressing-sparse-files.html
+            (DiskFileFormat::CompressedRaw, DiskFileFormat::Raw { is_sparse: true }) => {
+                let mut cmd = Command::new(constants::BASH_PROGRAM);
+                cmd.arg("-c").arg(format!(
+                    "{} -d -c {} | {} conv=sparse of={}",
+                    constants::GZIP_PROGRAM,
+                    self.file_path.display(),
+                    constants::DD_PROGRAM,
+                    temp_file.display()
+                ));
+                cmd
+            }
+
             // Dumb copy of file
             (a, b) if a == b => {
                 let mut cmd = Command::new(constants::COPY_PROGRAM);