tracer: refactor TracerMode to include foreground and impl it in eBPF…

… tracer

src/bpf.rs

@@ -425,7 +425,7 @@ impl EbpfTracer {
             .as_ref()
             .map(|tx| filterable_event!(TraceeSpawn(child)).send_if_match(tx, self.filter))
             .transpose()?;
-          if let TracerMode::Log | TracerMode::None = &self.mode {
+          if let TracerMode::Log { foreground: true } = &self.mode {
             match tcsetpgrp(stdin(), child) {
               Ok(_) => {}
               Err(Errno::ENOTTY) => {
@@ -451,7 +451,7 @@ impl EbpfTracer {
         ForkResult::Child => {
           let slave_pty = match &self.mode {
             TracerMode::Tui(tty) => tty.as_ref(),
-            TracerMode::Log | TracerMode::None => None,
+            _ => None,
           };
 
           if let Some(pts) = slave_pty {
@@ -573,7 +573,9 @@ pub async fn run(command: EbpfCommand, user: Option<User>, color: Color) -> colo
         baseline,
         tx: None,
         filter: TracerEventDetailsKind::empty(), // FIXME
-        mode: TracerMode::Log,
+        mode: TracerMode::Log {
+          foreground: log_args.foreground(),
+        },
       };
       let running_tracer = tracer.spawn(&mut obj, Some(output))?;
       running_tracer.run_until_exit();

src/cli/args.rs

@@ -290,13 +290,9 @@ pub struct LogModeArgs {
 impl LogModeArgs {
   pub fn foreground(&self) -> bool {
     match (self.foreground, self.no_foreground) {
-      (true, false) => true,
       (false, true) => false,
-      // Disable foreground mode in test by default
-      #[cfg(not(test))]
+      (true, false) => true,
       _ => true,
-      #[cfg(test)]
-      _ => false,
     }
   }
 

src/main.rs

@@ -105,7 +105,9 @@ async fn main() -> color_eyre::Result<()> {
       let (tracer_tx, mut tracer_rx) = mpsc::unbounded_channel();
       let (req_tx, req_rx) = mpsc::unbounded_channel();
       let tracer = Arc::new(tracer::Tracer::new(
-        TracerMode::Log,
+        TracerMode::Log {
+          foreground: tracing_args.foreground(),
+        },
         tracing_args,
         modifier_args,
         ptrace_args,
@@ -242,7 +244,9 @@ async fn main() -> color_eyre::Result<()> {
       let (req_tx, req_rx) = mpsc::unbounded_channel();
       let baseline = BaselineInfo::new()?;
       let tracer = Arc::new(tracer::Tracer::new(
-        TracerMode::None,
+        TracerMode::Log {
+          foreground: tracing_args.foreground(),
+        },
         tracing_args.clone(),
         modifier_args.clone(),
         ptrace_args,

src/tracer.rs

@@ -97,8 +97,7 @@ pub struct Tracer {
 
 pub enum TracerMode {
   Tui(Option<UnixSlavePty>),
-  Log,
-  None,
+  Log { foreground: bool },
 }
 
 #[derive(Debug, Clone, Copy, PartialEq)]
@@ -124,7 +123,7 @@ impl PartialEq for TracerMode {
     // I think a plain match is more readable here
     #[allow(clippy::match_like_matches_macro)]
     match (self, other) {
-      (Self::Log, Self::Log) => true,
+      (Self::Log { foreground: a }, Self::Log { foreground: b }) => a == b,
       _ => false,
     }
   }
@@ -162,8 +161,7 @@ impl Tracer {
     Ok(Self {
       with_tty: match &mode {
         TracerMode::Tui(tty) => tty.is_some(),
-        TracerMode::Log => true,
-        TracerMode::None => true,
+        TracerMode::Log { .. } => true,
       },
       store: RwLock::new(ProcessStateStore::new()),
       #[cfg(feature = "seccomp-bpf")]
@@ -173,7 +171,7 @@ impl Tracer {
       filter: {
         let mut filter = tracer_event_args.filter()?;
         trace!("Event filter: {:?}", filter);
-        if mode == TracerMode::Log {
+        if let TracerMode::Log { .. } = mode {
           // FIXME: In logging mode, we rely on root child exit event to exit the process
           //        with the same exit code as the root child. It is not printed in logging mode.
           //        Ideally we should use another channel to send the exit code to the main thread.
@@ -245,7 +243,7 @@ impl Tracer {
     let seccomp_bpf = self.seccomp_bpf;
     let slave_pty = match &self.mode {
       TracerMode::Tui(tty) => tty.as_ref(),
-      TracerMode::Log | TracerMode::None => None,
+      TracerMode::Log { .. } => None,
     };
     let with_tty = self.with_tty;
     let use_pseudo_term = slave_pty.is_some();
@@ -338,15 +336,13 @@ impl Tracer {
       self.store.write().unwrap().insert(root_child_state);
     }
     // Set foreground process group of the terminal
-    if let TracerMode::Log | TracerMode::None = &self.mode {
-      if self.foreground {
-        match tcsetpgrp(stdin(), root_child) {
-          Ok(_) => {}
-          Err(Errno::ENOTTY) => {
-            warn!("tcsetpgrp failed: ENOTTY");
-          }
-          r => r?,
+    if let TracerMode::Log { foreground: true } = &self.mode {
+      match tcsetpgrp(stdin(), root_child) {
+        Ok(_) => {}
+        Err(Errno::ENOTTY) => {
+          warn!("tcsetpgrp failed: ENOTTY");
         }
+        r => r?,
       }
     }
     let mut ptrace_opts = {

src/tracer/test.rs

@@ -23,7 +23,7 @@ fn tracer(
   UnboundedReceiver<TracerMessage>,
   UnboundedReceiver<PendingRequest>,
 ) {
-  let tracer_mod = TracerMode::Log;
+  let tracer_mod = TracerMode::Log { foreground: false };
   let tracing_args = LogModeArgs::default();
   let tracer_event_args = TracerEventArgs::all();
   let (msg_tx, msg_rx) = tokio::sync::mpsc::unbounded_channel();