From 0fc4819beec7a29b8a0b2b055694bd662d404c4a Mon Sep 17 00:00:00 2001
From: Bet4 <0xbet4@gmail.com>
Date: Thu, 30 Mar 2023 20:30:06 +0800
Subject: [PATCH] Toggle support for `QStartNoAckMode`

---
 example_no_std/src/gdb.rs  | 6 ++++++
 src/stub/core_impl/base.rs | 5 ++++-
 src/target/mod.rs          | 9 +++++++++
 3 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/example_no_std/src/gdb.rs b/example_no_std/src/gdb.rs
index ea6612b..76fa51d 100644
--- a/example_no_std/src/gdb.rs
+++ b/example_no_std/src/gdb.rs
@@ -22,6 +22,12 @@ impl Target for DummyTarget {
         target::ext::base::BaseOps::MultiThread(self)
     }
 
+    // disable `QStartNoAckMode`
+    #[inline(always)]
+    fn use_no_ack_mode(&self) -> bool {
+        false
+    }
+
     // disable X packet optimization in order to save space
     #[inline(always)]
     fn use_x_upcase_packet(&self) -> bool {
diff --git a/src/stub/core_impl/base.rs b/src/stub/core_impl/base.rs
index d5fe3b2..1fe6f0c 100644
--- a/src/stub/core_impl/base.rs
+++ b/src/stub/core_impl/base.rs
@@ -103,9 +103,12 @@ impl<T: Target, C: Connection> GdbStubImpl<T, C> {
                 res.write_str(concat!(
                     ";vContSupported+",
                     ";multiprocess+",
-                    ";QStartNoAckMode+",
                 ))?;
 
+                if target.use_no_ack_mode() {
+                    res.write_str(";QStartNoAckMode+",)?;
+                }
+
                 if let Some(resume_ops) = target.base_ops().resume_ops() {
                     let (reverse_cont, reverse_step) = match resume_ops {
                         ResumeOps::MultiThread(ops) => (
diff --git a/src/target/mod.rs b/src/target/mod.rs
index 985eea6..accc6ee 100644
--- a/src/target/mod.rs
+++ b/src/target/mod.rs
@@ -543,6 +543,14 @@ pub trait Target {
         true
     }
 
+    /// Enable/disable `QStartNoAckMode`
+    ///
+    /// By default, this method returns `true`.
+    #[inline(always)]
+    fn use_no_ack_mode(&self) -> bool {
+        true
+    }
+
     /// Whether `gdbstub` should provide a "stub" `resume` implementation on
     /// targets without support for resumption.
     ///
@@ -728,6 +736,7 @@ macro_rules! impl_dyn_target {
             __delegate!(fn guard_rail_single_step_gdb_behavior(&self) -> SingleStepGdbBehavior);
 
             __delegate!(fn use_x_upcase_packet(&self) -> bool);
+            __delegate!(fn use_no_ack_mode(&self) -> bool);
             __delegate!(fn use_resume_stub(&self) -> bool);
             __delegate!(fn use_rle(&self) -> bool);
             __delegate!(fn use_target_description_xml(&self) -> bool);