feat: adding piped process to replace PTY when needed (#8797)

codex-rs/core/src/exec.rs

@@ -32,6 +32,7 @@ use crate::sandboxing::SandboxPermissions;
 use crate::spawn::StdioPolicy;
 use crate::spawn::spawn_child_async;
 use crate::text_encoding::bytes_to_string_smart;
+use codex_utils_pty::process_group::kill_child_process_group;
 
 pub const DEFAULT_EXEC_COMMAND_TIMEOUT_MS: u64 = 10_000;
 
@@ -750,38 +751,6 @@ fn synthetic_exit_status(code: i32) -> ExitStatus {
     std::process::ExitStatus::from_raw(code as u32)
 }
 
-#[cfg(unix)]
-fn kill_child_process_group(child: &mut Child) -> io::Result<()> {
-    use std::io::ErrorKind;
-
-    if let Some(pid) = child.id() {
-        let pid = pid as libc::pid_t;
-        let pgid = unsafe { libc::getpgid(pid) };
-        if pgid == -1 {
-            let err = std::io::Error::last_os_error();
-            if err.kind() != ErrorKind::NotFound {
-                return Err(err);
-            }
-            return Ok(());
-        }
-
-        let result = unsafe { libc::killpg(pgid, libc::SIGKILL) };
-        if result == -1 {
-            let err = std::io::Error::last_os_error();
-            if err.kind() != ErrorKind::NotFound {
-                return Err(err);
-            }
-        }
-    }
-
-    Ok(())
-}
-
-#[cfg(not(unix))]
-fn kill_child_process_group(_: &mut Child) -> io::Result<()> {
-    Ok(())
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;

codex-rs/core/src/spawn.rs

@@ -70,8 +70,8 @@ pub(crate) async fn spawn_child_async(
         #[cfg(target_os = "linux")]
         let parent_pid = libc::getpid();
         cmd.pre_exec(move || {
-            if set_process_group && libc::setpgid(0, 0) == -1 {
-                return Err(std::io::Error::last_os_error());
+            if set_process_group {
+                codex_utils_pty::process_group::set_process_group()?;
             }
 
             // This relies on prctl(2), so it only works on Linux.
@@ -79,18 +79,7 @@ pub(crate) async fn spawn_child_async(
             {
                 // This prctl call effectively requests, "deliver SIGTERM when my
                 // current parent dies."
-                if libc::prctl(libc::PR_SET_PDEATHSIG, libc::SIGTERM) == -1 {
-                    return Err(std::io::Error::last_os_error());
-                }
-
-                // Though if there was a race condition and this pre_exec() block is
-                // run _after_ the parent (i.e., the Codex process) has already
-                // exited, then parent will be the closest configured "subreaper"
-                // ancestor process, or PID 1 (init). If the Codex process has exited
-                // already, so should the child process.
-                if libc::getppid() != parent_pid {
-                    libc::raise(libc::SIGTERM);
-                }
+                codex_utils_pty::process_group::set_parent_death_signal(parent_pid)?;
             }
             Ok(())
         });

codex-rs/core/src/tools/handlers/unified_exec.rs

@@ -33,6 +33,8 @@ struct ExecCommandArgs {
     shell: Option<String>,
     #[serde(default = "default_login")]
     login: bool,
+    #[serde(default = "default_tty")]
+    tty: bool,
     #[serde(default = "default_exec_yield_time_ms")]
     yield_time_ms: u64,
     #[serde(default)]
@@ -67,6 +69,10 @@ fn default_login() -> bool {
     true
 }
 
+fn default_tty() -> bool {
+    false
+}
+
 #[async_trait]
 impl ToolHandler for UnifiedExecHandler {
     fn kind(&self) -> ToolKind {
@@ -124,6 +130,7 @@ impl ToolHandler for UnifiedExecHandler {
 
                 let ExecCommandArgs {
                     workdir,
+                    tty,
                     yield_time_ms,
                     max_output_tokens,
                     sandbox_permissions,
@@ -173,6 +180,7 @@ impl ToolHandler for UnifiedExecHandler {
                             yield_time_ms,
                             max_output_tokens,
                             workdir,
+                            tty,
                             sandbox_permissions,
                             justification,
                         },

codex-rs/core/src/tools/runtimes/unified_exec.rs

@@ -37,6 +37,7 @@ pub struct UnifiedExecRequest {
     pub command: Vec<String>,
     pub cwd: PathBuf,
     pub env: HashMap<String, String>,
+    pub tty: bool,
     pub sandbox_permissions: SandboxPermissions,
     pub justification: Option<String>,
     pub exec_approval_requirement: ExecApprovalRequirement,
@@ -46,6 +47,7 @@ pub struct UnifiedExecRequest {
 pub struct UnifiedExecApprovalKey {
     pub command: Vec<String>,
     pub cwd: PathBuf,
+    pub tty: bool,
     pub sandbox_permissions: SandboxPermissions,
 }
 
@@ -58,6 +60,7 @@ impl UnifiedExecRequest {
         command: Vec<String>,
         cwd: PathBuf,
         env: HashMap<String, String>,
+        tty: bool,
         sandbox_permissions: SandboxPermissions,
         justification: Option<String>,
         exec_approval_requirement: ExecApprovalRequirement,
@@ -66,6 +69,7 @@ impl UnifiedExecRequest {
             command,
             cwd,
             env,
+            tty,
             sandbox_permissions,
             justification,
             exec_approval_requirement,
@@ -96,6 +100,7 @@ impl Approvable<UnifiedExecRequest> for UnifiedExecRuntime<'_> {
         vec![UnifiedExecApprovalKey {
             command: req.command.clone(),
             cwd: req.cwd.clone(),
+            tty: req.tty,
             sandbox_permissions: req.sandbox_permissions,
         }]
     }
@@ -189,7 +194,7 @@ impl<'a> ToolRuntime<UnifiedExecRequest, UnifiedExecProcess> for UnifiedExecRunt
             .env_for(spec)
             .map_err(|err| ToolError::Codex(err.into()))?;
         self.manager
-            .open_session_with_exec_env(&exec_env)
+            .open_session_with_exec_env(&exec_env, req.tty)
             .await
             .map_err(|err| match err {
                 UnifiedExecError::SandboxDenied { output, .. } => {

codex-rs/core/src/tools/spec.rs

@@ -168,6 +168,15 @@ fn create_exec_command_tool() -> ToolSpec {
                 ),
             },
         ),
+        (
+            "tty".to_string(),
+            JsonSchema::Boolean {
+                description: Some(
+                    "Whether to allocate a TTY for the command. Defaults to false (plain pipes); set to true to open a PTY and access TTY process."
+                        .to_string(),
+                ),
+            }
+        ),
         (
             "yield_time_ms".to_string(),
             JsonSchema::Number {

codex-rs/core/src/unified_exec/mod.rs

@@ -79,6 +79,7 @@ pub(crate) struct ExecCommandRequest {
     pub yield_time_ms: u64,
     pub max_output_tokens: Option<usize>,
     pub workdir: Option<PathBuf>,
+    pub tty: bool,
     pub sandbox_permissions: SandboxPermissions,
     pub justification: Option<String>,
 }
@@ -200,6 +201,7 @@ mod tests {
                     yield_time_ms,
                     max_output_tokens: None,
                     workdir: None,
+                    tty: true,
                     sandbox_permissions: SandboxPermissions::UseDefault,
                     justification: None,
                 },

codex-rs/core/src/unified_exec/process_manager.rs

@@ -126,6 +126,7 @@ impl UnifiedExecProcessManager {
                 cwd.clone(),
                 request.sandbox_permissions,
                 request.justification,
+                request.tty,
                 context,
             )
             .await;
@@ -442,21 +443,34 @@ impl UnifiedExecProcessManager {
     pub(crate) async fn open_session_with_exec_env(
         &self,
         env: &ExecEnv,
+        tty: bool,
     ) -> Result<UnifiedExecProcess, UnifiedExecError> {
         let (program, args) = env
             .command
             .split_first()
             .ok_or(UnifiedExecError::MissingCommandLine)?;
 
-        let spawned = codex_utils_pty::spawn_pty_process(
-            program,
-            args,
-            env.cwd.as_path(),
-            &env.env,
-            &env.arg0,
-        )
-        .await
-        .map_err(|err| UnifiedExecError::create_process(err.to_string()))?;
+        let spawn_result = if tty {
+            codex_utils_pty::pty::spawn_process(
+                program,
+                args,
+                env.cwd.as_path(),
+                &env.env,
+                &env.arg0,
+            )
+            .await
+        } else {
+            codex_utils_pty::pipe::spawn_process(
+                program,
+                args,
+                env.cwd.as_path(),
+                &env.env,
+                &env.arg0,
+            )
+            .await
+        };
+        let spawned =
+            spawn_result.map_err(|err| UnifiedExecError::create_process(err.to_string()))?;
         UnifiedExecProcess::from_spawned(spawned, env.sandbox).await
     }
 
@@ -466,6 +480,7 @@ impl UnifiedExecProcessManager {
         cwd: PathBuf,
         sandbox_permissions: SandboxPermissions,
         justification: Option<String>,
+        tty: bool,
         context: &UnifiedExecContext,
     ) -> Result<UnifiedExecProcess, UnifiedExecError> {
         let env = apply_unified_exec_env(create_env(&context.turn.shell_environment_policy));
@@ -488,6 +503,7 @@ impl UnifiedExecProcessManager {
             command.to_vec(),
             cwd,
             env,
+            tty,
             sandbox_permissions,
             justification,
             exec_approval_requirement,