ACTION!="add", GOTO="drivers_end"的意思

这同样是一个udev规则，通常存储在 /etc/udev/rules.d/ 目录下的 .rules 文件中。该规则的意思是：

如果一个设备不是 "add" 操作（例如，设备被删除），则执行一个 GOTO 操作，跳转到名为 "drivers_end" 的标签处，后面的规则将不再执行。

解释一下：

- ACTION!="add"：表示匹配除了 "add" 操作之外的所有操作，例如，删除设备的操作。
- GOTO="drivers_end"：表示执行一个跳转操作，跳转到名为 "drivers_end" 的标签处。

因此，该规则的作用是在设备被删除时，跳转到名为 "drivers_end" 的标签处，从而避免后面的规则被执行。这可以用于优化udev规则的执行效率，避免不必要的操作。

相关问题

WORD32 packetShadowDelete(SDDM_LPP_PACKET_KEY* pPacketKey, SDDM_LPP_PACKET* pPacketValue) { WORD32 dwRet = ROSNG_PARAM_ERROR; WORD32 so_desc = 0; WORD32 tcp_index = 0; if((NULL == pPacketKey) || (NULL == pPacketValue)) { ROSNG_TRACE_WARNING("Invalid para!!!\n"); goto error; } so_desc = pPacketValue->so_desc; tcp_index = pPacketValue->sddm_tcp_packet_cb.index; if((TCP_RECV_QUEUE == pPacketValue->pkt_queue) && (0 != so_desc)) { if(ROSNG_SUCCESS != packetShadowDeletePkt(&gSocketTable.packetRecvAvlTree,pPacketKey,pPacketValue,so_desc)) { ROSNG_TRACE_WARNING("packetShadowDeletePkt fail\n"); goto error; } } else if((TCP_SEND_QUEUE == pPacketValue->pkt_queue) && (0 != tcp_index)) { if(ROSNG_SUCCESS != packetShadowDeletePkt(&tcp_config.packetSendAvlTree,pPacketKey,pPacketValue,tcp_index)) { ROSNG_TRACE_WARNING("packetShadowDeletePkt fail\n"); goto error; } } else { XOS_ASSERT(0); goto error; } dwRet = ROSNG_SUCCESS; error: return dwRet; } 用c语言写一个ft测试用例

以下是一个简单的ft测试用例，测试packetShadowDelete函数是否能够正常处理输入参数并返回正确的结果。

#include <stdio.h>
#include <assert.h>

typedef unsigned int WORD32;

typedef struct {
    WORD32 index;
} SDDM_TCP_PACKET_CB;

typedef struct {
    WORD32 so_desc;
    SDDM_TCP_PACKET_CB sddm_tcp_packet_cb;
    WORD32 pkt_queue;
} SDDM_LPP_PACKET;

typedef struct {
    // some fields
} SDDM_LPP_PACKET_KEY;

#define TCP_RECV_QUEUE 0
#define TCP_SEND_QUEUE 1

#define ROSNG_SUCCESS 0
#define ROSNG_PARAM_ERROR -1

#define ROSNG_TRACE_WARNING(...) printf(__VA_ARGS__)
#define XOS_ASSERT(...) assert(__VA_ARGS__)

typedef struct {
    // some fields
} PacketAvlTree;

PacketAvlTree packetRecvAvlTree;
PacketAvlTree packetSendAvlTree;

WORD32 packetShadowDeletePkt(PacketAvlTree* tree, SDDM_LPP_PACKET_KEY* key, SDDM_LPP_PACKET* value, WORD32 index) {
    // some implementation
    return ROSNG_SUCCESS;
}

WORD32 packetShadowDelete(SDDM_LPP_PACKET_KEY* pPacketKey, SDDM_LPP_PACKET* pPacketValue) {
    WORD32 dwRet = ROSNG_PARAM_ERROR;
    WORD32 so_desc = 0;
    WORD32 tcp_index = 0;

    if((NULL == pPacketKey) || (NULL == pPacketValue))
    {
        ROSNG_TRACE_WARNING("Invalid para!!!\n");
        goto error;
    }

    so_desc = pPacketValue->so_desc;
    tcp_index = pPacketValue->sddm_tcp_packet_cb.index;

    if((TCP_RECV_QUEUE == pPacketValue->pkt_queue) && (0 != so_desc))
    {
        if(ROSNG_SUCCESS != packetShadowDeletePkt(&packetRecvAvlTree,pPacketKey,pPacketValue,so_desc))
        {
            ROSNG_TRACE_WARNING("packetShadowDeletePkt fail\n");
            goto error;
        }
    }
    else if((TCP_SEND_QUEUE == pPacketValue->pkt_queue) && (0 != tcp_index))
    {
        if(ROSNG_SUCCESS != packetShadowDeletePkt(&packetSendAvlTree,pPacketKey,pPacketValue,tcp_index))
        {
            ROSNG_TRACE_WARNING("packetShadowDeletePkt fail\n");
            goto error;
        }
    }
    else
    {
        XOS_ASSERT(0);
        goto error;
    }

    dwRet = ROSNG_SUCCESS;

error:
    return dwRet;
}

int main() {
    SDDM_LPP_PACKET_KEY key;
    key.some_field = 123;

    SDDM_LPP_PACKET value;
    value.so_desc = 456;
    value.sddm_tcp_packet_cb.index = 789;
    value.pkt_queue = TCP_RECV_QUEUE;

    WORD32 ret = packetShadowDelete(&key, &value);
    assert(ret == ROSNG_SUCCESS);

    return 0;
}

优化以下代码：int MainWindow::ONVIF_GetDeviceInformation(const char *DeviceXAddr) { int result = 0; struct soap *soap = NULL; _tds__GetDeviceInformation * devinfo_req; _tds__GetDeviceInformationResponse * devinfo_resp; SOAP_ASSERT(NULL != DeviceXAddr); SOAP_ASSERT(NULL != (soap = ONVIF_soap_new(SOAP_SOCK_TIMEOUT))); memset(&devinfo_req, 0x00, sizeof(devinfo_req)); memset(&devinfo_resp, 0x00, sizeof(devinfo_resp)); result = soap_call___tds__GetDeviceInformation(soap, DeviceXAddr, NULL, devinfo_req, devinfo_resp); SOAP_CHECK_ERROR(result, soap, "GetDeviceInformation"); dump_tds__GetDeviceInformationResponse(devinfo_resp); EXIT: if (NULL != soap) { ONVIF_soap_delete(soap); } return result; }

优化后的代码如下：

int MainWindow::ONVIF_GetDeviceInformation(const char *DeviceXAddr) {
    int result = 0;
    struct soap *soap = ONVIF_soap_new(SOAP_SOCK_TIMEOUT);
    if (soap == NULL) {
        return SOAP_ERR;
    }

    _tds__GetDeviceInformation devinfo_req;
    _tds__GetDeviceInformationResponse devinfo_resp;

    memset(&devinfo_req, 0x00, sizeof(devinfo_req));
    memset(&devinfo_resp, 0x00, sizeof(devinfo_resp));

    result = soap_call___tds__GetDeviceInformation(soap, DeviceXAddr, NULL, &devinfo_req, &devinfo_resp);
    SOAP_CHECK_ERROR(result, soap, "GetDeviceInformation");

    dump_tds__GetDeviceInformationResponse(&devinfo_resp);

EXIT:
    ONVIF_soap_delete(soap);
    return result;
}

优化点如下：

1. 减少了多余的 NULL 判断，使用 ONVIF_soap_new 函数直接创建并初始化了 soap 对象。
2. 去掉了不必要的结构体指针，直接定义结构体变量 devinfo_req 和 devinfo_resp。
3. 修正了调用 soap_call___tds__GetDeviceInformation 函数时的参数类型，将结构体指针改为结构体变量的地址。
4. 去掉了 goto 语句，改用代码块 EXIT 来进行错误处理和资源释放。