feat: add gdbserver support for native code debugging

.devcontainer/install-deps.sh

@@ -18,6 +18,7 @@ sudo apt-get install -y --no-install-recommends \
   build-essential \
   device-tree-compiler \
   gperf g++-multilib gcc-multilib \
+  gdb-multiarch \
   libnl-3-dev libdbus-1-dev libelf-dev libmpc-dev dwarves \
   bc openssl flex bison libssl-dev python3 python-is-python3 texinfo kmod cmake \
   wget zstd \

.vscode/launch.json

@@ -0,0 +1,28 @@
+{
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "GDB Debug - Native (binary)",
+            "type": "cppdbg",
+            "request": "launch",
+            "program": "internal/native/cgo/build/jknative-bin",
+            "args": [],
+            "stopAtEntry": true,
+            "cwd": "${workspaceFolder}",
+            "environment": [],
+            "MIMode": "gdb",
+            "miDebuggerPath": "/usr/bin/gdb-multiarch",
+            "miDebuggerServerAddress": "${config:TARGET_IP}:${config:DEBUG_PORT}",
+            "targetArchitecture": "arm",
+            "preLaunchTask": "deploy",
+            "setupCommands": [
+                {
+                    "description": "Pretty-printing for gdb",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                }
+            ],
+            "externalConsole": true
+        }
+    ]
+}

.vscode/settings.json

@@ -14,5 +14,12 @@
   "cmake.ignoreCMakeListsMissing": true,
   "C_Cpp.inlayHints.autoDeclarationTypes.enabled": true,
   "C_Cpp.inlayHints.parameterNames.enabled": true,
-  "C_Cpp.inlayHints.referenceOperator.enabled": true
+  "C_Cpp.inlayHints.referenceOperator.enabled": true,
+  "files.associations": {
+    "*.yml": "yaml",
+    "*.libsonet": "jsonnet",
+    "rk_comm_mb.h": "c"
+  },
+  "TARGET_IP": "192.168.0.199",
+  "DEBUG_PORT": "2345",
 }

.vscode/tasks.json

@@ -0,0 +1,30 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "deploy",
+            "isBackground": true,
+            "type": "shell",
+            "command": "bash",
+            "args": [
+                "dev_deploy.sh",
+                "-r",
+                "${config:TARGET_IP}",
+                "--gdb-port",
+                "${config:DEBUG_PORT}",
+                "--native-binary",
+                "--disable-docker"
+            ],
+            "problemMatcher": {
+                "base": "$gcc",
+                "background": {
+                    "activeOnStart": true,
+                    "beginsPattern": "${config:BINARY}",
+                    "endsPattern": "Listening on port [0-9]{4}"
+                }
+            }
+        },
+    ]
+}

DEVELOPMENT.md

@@ -208,6 +208,12 @@ rm /userdata/kvm_config.json
 systemctl restart jetkvm
 ```
 
+### Debug native code with gdbserver
+
+Change the `TARGET_IP` in `.vscode/settings.json` to your JetKVM device IP, then set breakpoints in your native code and start the `Debug Native` configuration in VSCode.
+
+The code and GDB server will be deployed automatically.
+
 ---
 
 ## Testing Your Changes

Makefile

@@ -14,6 +14,8 @@ SKIP_NATIVE_IF_EXISTS ?= 0
 SKIP_UI_BUILD ?= 0
 ENABLE_SYNC_TRACE ?= 0
 
+CMAKE_BUILD_TYPE ?= Release
+
 GO_BUILD_ARGS := -tags netgo,timetzdata,nomsgpack
 ifeq ($(ENABLE_SYNC_TRACE), 1)
 	GO_BUILD_ARGS := $(GO_BUILD_ARGS),synctrace
@@ -52,6 +54,7 @@ build_native:
 		echo "Building native..."; \
 			CC="$(BUILDKIT_PATH)/bin/$(BUILDKIT_FLAVOR)-gcc" \
 			LD="$(BUILDKIT_PATH)/bin/$(BUILDKIT_FLAVOR)-ld" \
+			CMAKE_BUILD_TYPE=$(CMAKE_BUILD_TYPE) \
 			./scripts/build_cgo.sh; \
 	fi
 

scripts/build_cgo.sh

@@ -4,6 +4,8 @@ set -e
 SCRIPT_PATH=$(realpath "$(dirname $(realpath "${BASH_SOURCE[0]}"))")
 source ${SCRIPT_PATH}/build_utils.sh
 
+CMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE:-Release}
+
 CGO_PATH=$(realpath "${SCRIPT_PATH}/../internal/native/cgo")
 BUILD_DIR=${CGO_PATH}/build
 
@@ -31,7 +33,7 @@ VERBOSE=1 cmake -B "${BUILD_DIR}" \
     -DCONFIG_LV_BUILD_EXAMPLES=OFF \
     -DCONFIG_LV_BUILD_DEMOS=OFF \
     -DSKIP_GLIBC_NAMES=ON \
-    -DCMAKE_BUILD_TYPE=Release \
+    -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} \
     -DCMAKE_INSTALL_PREFIX="${TMP_DIR}"
 
 msg_info "▶ Copying built library and header files"

scripts/dev_deploy.sh

@@ -12,6 +12,7 @@ show_help() {
     echo
     echo "Optional:"
     echo "  -u, --user <remote_user>   Remote username (default: root)"
+    echo "      --gdb-port <port>      GDB debug port (default: 2345)"
     echo "      --run-go-tests         Run go tests"
     echo "      --run-go-tests-only    Run go tests and exit"
     echo "      --skip-ui-build        Skip frontend/UI build"
@@ -59,6 +60,7 @@ REMOTE_PATH="/userdata/jetkvm/bin"
 SKIP_UI_BUILD=false
 SKIP_UI_BUILD_RELEASE=0
 SKIP_NATIVE_BUILD=0
+GDB_DEBUG_PORT=2345
 BUILD_NATIVE_BINARY=false
 ENABLE_SYNC_TRACE=0
 RESET_USB_HID_DEVICE=false
@@ -81,6 +83,10 @@ while [[ $# -gt 0 ]]; do
             REMOTE_USER="$2"
             shift 2
             ;;
+        --gdb-port)
+            GDB_DEBUG_PORT="$2"
+            shift 2
+            ;;
         --skip-ui-build)
             SKIP_UI_BUILD=true
             shift
@@ -148,7 +154,8 @@ fi
 check_ping "${REMOTE_HOST}"
 check_ssh "${REMOTE_USER}" "${REMOTE_HOST}"
 function sshdev() {
-    ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no "${REMOTE_USER}@${REMOTE_HOST}" $@
+    ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no "${REMOTE_USER}@${REMOTE_HOST}" "$@"
+    return $?
 }
 
 # check if the current CPU architecture is x86_64
@@ -163,10 +170,17 @@ fi
 
 if [ "$BUILD_NATIVE_BINARY" = true ]; then
     msg_info "▶ Building native binary"
-    make build_native
-    sshdev "killall -9 jetkvm_app jetkvm_app_debug jetkvm_native_debug || true"
+    CMAKE_BUILD_TYPE=Debug make build_native
+    msg_info "▶ Checking if GDB is available on remote host"
+    if ! sshdev "command -v gdbserver > /dev/null 2>&1"; then
+        msg_warn "Error: gdbserver is not installed on the remote host"
+        tar -czf - -C /opt/jetkvm-native-buildkit/gdb/ . | sshdev "tar -xzf - -C /usr/bin"
+        msg_info "✓ gdbserver installed on remote host"
+    fi
+    msg_info "▶ Stopping any existing instances of jetkvm_native_debug on remote host"
+    sshdev "killall -9 jetkvm_app jetkvm_app_debug jetkvm_native_debug gdbserver || true >> /dev/null 2>&1"
     sshdev "cat > ${REMOTE_PATH}/jetkvm_native_debug" < internal/native/cgo/build/jknative-bin
-    sshdev ash << EOF
+    sshdev -t ash << EOF
 set -e
 
 # Set the library path to include the directory where librockit.so is located
@@ -177,7 +191,7 @@ killall -9 jetkvm_app jetkvm_app_debug jetkvm_native_debug || true
 sleep 5
 echo 'V' > /dev/watchdog
 chmod +x jetkvm_native_debug
-./jetkvm_native_debug
+gdbserver localhost:${GDB_DEBUG_PORT} ./jetkvm_native_debug
 EOF
     exit 0
 fi