Merge pull request #184 from nix-community/improve-subprocess-errors

tool: improve command error messages

rust/tool/src/pe.rs

@@ -71,7 +71,7 @@ fn wrap_in_pe(stub: &Path, sections: Vec<Section>, output: &Path) -> Result<()>
     let status = Command::new("objcopy")
         .args(&args)
         .status()
-        .context("Failed to run objcopy command")?;
+        .context("Failed to run objcopy. Most likely, the binary is not on PATH.")?;
     if !status.success() {
         return Err(anyhow::anyhow!(
             "Failed to wrap in pe with args `{:?}`",

rust/tool/src/signature.rs

@@ -29,7 +29,10 @@ impl KeyPair {
             to.as_os_str().to_owned(),
         ];
 
-        let output = Command::new("sbsign").args(&args).output()?;
+        let output = Command::new("sbsign")
+            .args(&args)
+            .output()
+            .context("Failed to run sbsign. Most likely, the binary is not on PATH.")?;
 
         if !output.status.success() {
             std::io::stderr()
@@ -50,10 +53,10 @@ impl KeyPair {
             path.as_os_str().to_owned(),
         ];
 
-        let output = match Command::new("sbverify").args(&args).output() {
+        let output = Command::new("sbverify")
-            Ok(output) => output,
+            .args(&args)
-            Err(_) => return false,
+            .output()
-        };
+            .expect("Failed to run sbverify. Most likely, the binary is not on PATH.");
 
         if !output.status.success() {
             if std::io::stderr().write_all(&output.stderr).is_err() {

rust/tool/tests/common/mod.rs

@@ -182,7 +182,8 @@ pub fn remove_signature(path: &Path) -> Result<()> {
     let output = Command::new("sbattach")
         .arg("--remove")
         .arg(path.as_os_str())
-        .output()?;
+        .output()
+        .context("Failed to run sbattach. Most likely, the binary is not on PATH.")?;
     print!("{}", String::from_utf8(output.stdout)?);
     print!("{}", String::from_utf8(output.stderr)?);
     Ok(())
@@ -194,7 +195,8 @@ pub fn verify_signature(path: &Path) -> Result<bool> {
         .arg(path.as_os_str())
         .arg("--cert")
         .arg("tests/fixtures/uefi-keys/db.pem")
-        .output()?;
+        .output()
+        .context("Failed to run sbverify. Most likely, the binary is not on PATH.")?;
     print!("{}", String::from_utf8(output.stdout)?);
     print!("{}", String::from_utf8(output.stderr)?);
     Ok(output.status.success())