start on image

4 files changed, 53 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index fac79e6..77bb5c4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,3 +7,4 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+thiserror = "1"
diff --git a/src/errors.rs b/src/errors.rs
new file mode 100644
index 0000000..ba7875a
--- /dev/null
+++ b/src/errors.rs
@@ -0,0 +1,4 @@
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+pub enum VmadminError {}
diff --git a/src/image.rs b/src/image.rs
new file mode 100644
index 0000000..e0b5a98
--- /dev/null
+++ b/src/image.rs
@@ -0,0 +1,47 @@
+use std::fs::copy;
+use std::path::{Path, PathBuf};
+use std::process::Command;
+use std::result::Result;
+
+#[derive(Debug, thiserror::Error)]
+pub enum ImageError {
+    #[error("qemu-img resize failed: {0}")]
+    ResizeError(String),
+
+    #[error(transparent)]
+    IoError(#[from] std::io::Error),
+
+    #[error(transparent)]
+    StringError(#[from] std::string::FromUtf8Error),
+}
+
+pub struct VirtualMachineImage {
+    filename: PathBuf,
+}
+
+impl VirtualMachineImage {
+    pub fn new_from_base(base_image: &Path, image: &Path) -> Result<Self, ImageError> {
+        copy(base_image, image)?;
+        Ok(Self {
+            filename: image.to_path_buf(),
+        })
+    }
+
+    pub fn filename(&self) -> &Path {
+        &self.filename
+    }
+
+    pub fn resize(&self, new_size: usize) -> Result<(), ImageError> {
+        let r = Command::new("qemu-img")
+            .arg("resize")
+            .arg("-f")
+            .arg(self.filename())
+            .arg(format!("{}", new_size))
+            .output()?;
+        if !r.status.success() {
+            let stderr = String::from_utf8(r.stderr)?;
+            return Err(ImageError::ResizeError(stderr));
+        }
+        Ok(())
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index 3766a04..16a21b3 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1 +1,2 @@
 pub mod cloudinit;
+pub mod image;