Merge pull request 'feat: ambient-run extracts run exit code and checks it' (#28) from exit-code into main

Reviewed-on: https://codeberg.org/ambient/ambient-run/pulls/28

4 files changed, 61 insertions, 10 deletions

diff --git a/ambient-run.md b/ambient-run.md
index 7be3be6..b3cee4a 100644
--- a/ambient-run.md
+++ b/ambient-run.md
@@ -275,8 +275,9 @@ given an installed ambient-run
 given file no-artifact-project.yaml
 given file foo/README.md from foo-project.yaml
 given image file image.qcow2 specified for test suite
-when I run ambient-run build no-artifact-project.yaml --log foo.log
+when I try to run ambient-run build no-artifact-project.yaml --log foo.log
 then file foo.log contains "EXIT CODE: 2"
+then exit code is 1
 ~~~
 
 
@@ -303,8 +304,9 @@ given an installed ambient-run
 given file small-artifact-project.yaml
 given file foo/README.md from foo-project.yaml
 given image file image.qcow2 specified for test suite
-when I run ambient-run build small-artifact-project.yaml --log foo.log
+when I try to run ambient-run build small-artifact-project.yaml --log foo.log
 then file foo.log contains "EXIT CODE: 2"
+then exit code is 1
 ~~~
 
 
@@ -461,7 +463,7 @@ then file extracted/README.md contains "my project!"
 ~~~
 
 ## Errors during build
-### Bad  per-user configuration
+### Bad per-user configuration
 
 _Requirement:_ `ambient-run` fails if the per-user configuration is
 bad.
diff --git a/src/bin/ambient-run.rs b/src/bin/ambient-run.rs
index 6083286..602e4d6 100644
--- a/src/bin/ambient-run.rs
+++ b/src/bin/ambient-run.rs
@@ -224,7 +224,12 @@ impl BuildCommand {
         if let Some(log) = &self.log {
             qemu = qemu.with_log(log);
         }
-        qemu.run()?;
-        Ok(())
+        let exit = qemu.run()?;
+        eprintln!("ambient-run build exit code {exit}");
+        if exit == 0 {
+            Ok(())
+        } else {
+            Err(AmbientRunError::RunFailed(exit))
+        }
     }
 }
diff --git a/src/error.rs b/src/error.rs
index 0958d35..e55dcde 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -12,6 +12,9 @@ pub enum AmbientRunError {
     #[error(transparent)]
     Qemu(#[from] crate::qemu::QemuError),
 
+    #[error("run in VM failed with exit code {0}")]
+    RunFailed(i32),
+
     #[error(transparent)]
     VDrive(#[from] crate::vdrive::VirtualDriveError),
 }
diff --git a/src/qemu.rs b/src/qemu.rs
index a3e344d..d1b0761 100644
--- a/src/qemu.rs
+++ b/src/qemu.rs
@@ -5,7 +5,7 @@ use crate::vdrive::{VirtualDrive, VirtualDriveBuilder, VirtualDriveError};
 use std::{
     fs::{copy, write, File},
     path::{Path, PathBuf},
-    process::{Command, Stdio},
+    process::Command,
 };
 
 const MAX_OUTPUT_SIZE: u64 = 1024 * 1024 * 1024;
@@ -78,7 +78,7 @@ impl Qemu {
     }
 
     /// Run QEMU in the specified way.
-    pub fn run(&self) -> Result<(), QemuError> {
+    pub fn run(&self) -> Result<i32, QemuError> {
         eprintln!("qemu run");
         let tmp = tempfile::tempdir().map_err(QemuError::TempDir)?;
         let empty = tempfile::tempdir().map_err(QemuError::TempDir)?;
@@ -156,7 +156,6 @@ impl Qemu {
             .with_raw(cache_drive.filename(), false)
             .with_raw(deps_drive.filename(), true)
             .with_arg("-nodefaults");
-        eprintln!("Args: {:#?}", args);
 
         eprintln!("spawn qemu");
         let child = Command::new("kvm")
@@ -180,7 +179,11 @@ impl Qemu {
                     .extract_to(dirname)
                     .map_err(|e| QemuError::ExtractCache(dirname.into(), e))?;
             }
-            Ok(())
+            eprintln!("reading build log");
+            let log = Self::build_log(&build_log)?;
+            eprintln!("log:\n{}", log);
+            let exit = Self::exit_code(&log)?;
+            Ok(exit)
         } else {
             let exit = output.status.code().unwrap_or(255);
             let out = String::from_utf8_lossy(&output.stdout).to_string();
@@ -191,7 +194,7 @@ impl Qemu {
                 "kvm failed: exit={}\nstdout: {:?}\nstderr: {:?}\nVM console: {:?}",
                 exit, out, err, log
             );
-            Err(QemuError::Kvm(exit, err, log))
+            Ok(exit)
         }
     }
 
@@ -205,6 +208,38 @@ impl Qemu {
         Ok(filename.into())
     }
 
+    fn build_log(filename: &Path) -> Result<String, QemuError> {
+        const BEGIN: &str = "====================== BEGIN ======================";
+        const END: &str = "====================== END ======================";
+
+        let log = std::fs::read(filename).map_err(|e| QemuError::ReadLog(filename.into(), e))?;
+        let log = String::from_utf8_lossy(&log);
+
+        if let Some((_, log)) = log.split_once(BEGIN) {
+            if let Some((log, _)) = log.split_once(END) {
+                return Ok(log.into());
+            }
+        }
+
+        Ok("".into())
+    }
+
+    fn exit_code(log: &str) -> Result<i32, QemuError> {
+        const EXIT: &str = "\nEXIT CODE: ";
+        if let Some((_, rest)) = log.split_once(EXIT) {
+            eprintln!("log has {:?}", EXIT);
+            if let Some((exit, _)) = rest.split_once('\n') {
+                eprintln!("log has newline after exit: {:?}", exit);
+                if let Ok(exit) = exit.trim().parse::<i32>() {
+                    eprintln!("log exit coded parses ok: {}", exit);
+                    return Ok(exit);
+                }
+                eprintln!("log exit does not parse");
+            }
+        }
+        Err(QemuError::NoExit)
+    }
+
     fn create_tar(tar_filename: PathBuf, dirname: &Path) -> Result<VirtualDrive, QemuError> {
         let tar = VirtualDriveBuilder::default()
             .filename(&tar_filename)
@@ -315,6 +350,9 @@ pub enum QemuError {
     #[error("failed to write temporary file")]
     Write(#[source] std::io::Error),
 
+    #[error("failed to read log file {0}")]
+    ReadLog(PathBuf, #[source] std::io::Error),
+
     #[error("failed to open log file for writing")]
     Log(PathBuf, #[source] std::io::Error),
 
@@ -329,6 +367,9 @@ pub enum QemuError {
 
     #[error("failed to read temporary file for logging")]
     TemporaryLog(#[source] std::io::Error),
+
+    #[error("build log lacks exit code of run")]
+    NoExit,
 }
 
 #[cfg(test)]