如何在VSCode的launch.json中通过Bash命令动态配置调试地址？

我的VS Code中launch.json包含如下调试配置：

{
    "request": "launch",
    "type": "cortex-debug",
    "name": "Rt117xDemo Start",
    "cwd": "${workspaceFolder}",
    "executable": "${workspaceFolder}/FW/image/Rt117xDemo.elf",
    "servertype": "jlink",
    "device": "MIMXRT1176xxxA_M7",
    "interface": "swd",
    "rtos": "FreeRTOS",
    "svdFile": "${workspaceFolder}/FW/bsp/device/MIMXRT1175_cm7.svd",
    "runToEntryPoint": "main",
    "preLaunchTask": "build",
    "serverArgs": [
        "-gui"
    ],
    "preLaunchCommands": [
        "directory ${workspaceFolder}/FW"
    ],
    "postLaunchCommands": [
        "monitor reg pc 0x30002100"
    ]
}

我希望将postLaunchCommands中的固定地址0x30002100替换为Bash命令的输出，且每次启动调试（尤其是执行构建任务后）都自动运行该命令获取最新地址。

2023-06-23 更新
具体需要执行的Bash命令为从编译生成的ELF文件提取入口地址：

/path/to/arm-none-eabi-readelf -l ${workspaceFolder}/FW/image/Rt117xDemo.elf | sed -n 's/Entry point \(0x[[:xdigit:]]\{8\}\)/\1/p'

期望launch.json能写成类似如下形式：

"postLaunchCommands": [
    "monitor reg pc ${command: 此处填入命令输出}"
]

方法一：使用Command Variable扩展（推荐） #

1. 安装VS Code扩展：Command Variable（作者：rioj7）
2. 修改launch.json中的postLaunchCommands配置，注意JSON语法要求反斜杠需转义（\改为\\）：

"postLaunchCommands": [
    "monitor reg pc ${command:extension.commandvariable.shell.execute(/path/to/arm-none-eabi-readelf -l ${workspaceFolder}/FW/image/Rt117xDemo.elf | sed -n 's/Entry point \\(0x[[:xdigit:]]\\{8\\}\\)/\\1/p')}"
]

该配置会在每次启动调试时自动执行指定Bash命令，将输出结果直接替换到pc寄存器的赋值位置。

方法二：自定义任务+输入变量 #

1. 在.vscode/tasks.json中添加一个用于提取入口地址的任务：

{
    "version": "2.0.0",
    "tasks": [
        {
            "label": "fetch-entry-address",
            "type": "shell",
            "command": "/path/to/arm-none-eabi-readelf -l ${workspaceFolder}/FW/image/Rt117xDemo.elf | sed -n 's/Entry point \\(0x[[:xdigit:]]\\{8\\}\\)/\\1/p'",
            "problemMatcher": [],
            "presentation": {
                "echo": false,
                "reveal": "never"
            },
            "outputCapture": "stdout"
        }
    ]
}

2. 在launch.json中添加输入配置，并更新postLaunchCommands：

{
    // 保留原有调试配置项...
    "inputs": [
        {
            "id": "entryAddress",
            "type": "command",
            "command": "extension.commandvariable.task.output",
            "args": {
                "task": "fetch-entry-address",
                "line": 0,
                "trim": true
            }
        }
    ],
    "postLaunchCommands": [
        "monitor reg pc ${input:entryAddress}"
    ]
}

此方法通过先执行任务获取地址，再将任务输出作为变量传入调试命令，确保每次调试都能获取最新的入口地址。

内容的提问来源于stack exchange，提问作者mastupristi