[lwip/core/dhcp.c]Fixed incorrect pairing of DHCP enable/disable in lwip (≤v2.0.3)

[Rbb666]

Fixed incorrect pairing of DHCP enable/disable in lwip (≤v2.0.3)

测试发现 lwip (≤v2.0.3) 版本成对调用打开和关闭DHCP的API的时候，会出现：dhcp_create_msg: dhcp->p_out == NULL 断言错误，在 v2.1.2后lwip源码已经修复此问题

测试代码如下：

static void test_netdev_dhcp(void)
{
    rt_err_t res;
    rt_bool_t initial_state;

    /* Save initial DHCP state */
    initial_state = netdev_is_dhcp_enabled(netdev_default);

    /* DHCP disable */
    res = netdev_dhcp_enabled(netdev_default, RT_FALSE);
    if (res == RT_EOK)
    {
        uassert_false(netdev_is_dhcp_enabled(netdev_default));
    }
    else
    {
        uassert_true(RT_FALSE);
        return;
    }

    /* Restore initial state */
    res = netdev_dhcp_enabled(netdev_default, initial_state);
    uassert_true(res == RT_EOK);
}

[github-actions]

📌 Code Review Assignment

🏷️ Tag: components

Reviewers: Maihuanyi

Changed Files (Click to expand)

• components/net/lwip/lwip-1.4.1/src/core/dhcp.c
• components/net/lwip/lwip-2.0.3/src/core/ipv4/dhcp.c

---

📊 Current Review Status (Last Updated: 2025-09-13 20:12 CST)

• ⌛ Maihuanyi Pending Review

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[Rbb666]

@Ryan-CW-Code 大佬帮看看

[Ryan-CW-Code]

感觉尽量不修改lwip的源代码比较好，尽量不增加修改源码的地方了。
看看netifapi_dhcp_start和netifapi_dhcp_stop这种线程安全封装可以不