GetCapabilities:获取能力,主要目的获取设备能力信息（获取媒体服务地址）

鉴权：但是在调用获取设备能力之前是需要鉴权的。ONVIF协议规定，部分接口需要鉴权，部分接口不需要鉴权，在调用需要鉴权的接口时不使用鉴权，会导致接口调用失败。实现鉴权的方式之一可以调用gSOAP源码中的 soap_wsse_add_UsernameTokenDigest()函数。要安装依赖库OpenSSL

关于完整ipc摄像头设备的发现、GetCapabilities、GetServices、 GetProfiles、 GetStreamUri可以查看之前的文章：

https://blog.csdn.net/weixin_42432281/article/details/84837192

实现代码：

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

#include "soapH.h"
#include "stdsoap2.h"
#include "soapStub.h"
#include "wsseapi.h"

#include "wsdd.nsmap" //命名空间

static struct soap* ONVIF_Initsoap(struct SOAP_ENV__Header *header, const char *was_To, const char *was_Action, int timeout)
{
    struct soap *soap = NULL;    // soap环境变量
    unsigned char macaddr[6];
    char _HwId[1024];
    unsigned int Flagrand;

    soap = soap_new();
    if(soap == NULL)
    {
        printf("[%d]soap = NULL\n", __LINE__);
        return NULL;
    }

    soap_set_namespaces(soap, namespaces);   // 设置soap的namespaces，即设置命名空间

    // 设置超时（超过指定时间没有数据就退出）
    if(timeout > 0)
    {
        soap->recv_timeout = timeout;
        soap->send_timeout = timeout;
        soap->connect_timeout = timeout;
    }
    else
    {
        //Maximum waittime : 20s
        soap->recv_timeout  = 20;
        soap->send_timeout  = 20;
        soap->connect_timeout = 20;
    }

    soap_default_SOAP_ENV__Header(soap, header);

    //Create SessionID randomly,生成uuid(windows下叫guid，linux下叫uuid)，格式为urn:uuid:8-4-4-4-12，由系统随机产生
    srand((int)time(0));
    Flagrand = rand()%9000 + 8888;
    macaddr[0] = 0x1;
    macaddr[1] = 0x2;
    macaddr[2] = 0x3;
    macaddr[3] = 0x4;
    macaddr[4] = 0x5;
    macaddr[5] = 0x6;
    sprintf(_HwId, "urn:uuid:%ud68a-1dd2-11b2-a105-%02X%02X%02X%02X%02X%02X", Flagrand, macaddr[0], macaddr[1], macaddr[2],macaddr[3],macaddr[4],macaddr[5]);
    header->wsa__MessageID = (char *)malloc(100);  
    memset(header->wsa__MessageID, 0, 100);
    strncpy(header->wsa__MessageID, _HwId, strlen(_HwId));    //wsa__MessageID存放的是uuid

    if(was_Action != NULL)
    {
        header->wsa__Action = (char*)malloc(1024);
        memset(header->wsa__Action, '\0', 1024);
        strncpy(header->wsa__Action, was_Action, 1024); //
    }
    if(was_To != NULL)
    {
        header->wsa__To = (char *)malloc(1024);
        memset(header->wsa__To, '\0', 1024);
        strncpy(header->wsa__To, was_To, 1024);//"urn:schemas-xmlsoap-org:ws:2005:04:discovery";
    }
    soap->header = header;
    return soap;
}


//释放函数
void ONVIF_soap_delete(struct soap *soap)
{
    soap_destroy(soap);                      // remove deserialized class instances (C++ only)
    soap_end(soap);                          // Clean up deserialized data (except class instances) and temporary data
    soap_free(soap);                         // Reset and deallocate the context created with soap_new or soap_copy
}


//鉴权
static int ONVIF_SetAuthInfo(struct soap *soap, const char *username, const char *password)
{
    int result = 0;
    if((NULL != username) || (NULL != password)){
        soap_wsse_add_UsernameTokenDigest(soap, NULL, username, password);
    }else{
        printf("un etAuth\n");
        result = -1;
    }

    return result;
}



int main(int argc,char *argv[])
{
    int ret = 0;
    char sercer_addr[] = "http://172.168.0.211/onvif/device_service"; //设备搜索得到的地址

    struct SOAP_ENV__Header header;
    struct soap* soap = ONVIF_Initsoap(&header, NULL, NULL, 5);

    struct _tds__GetCapabilities *req;
    struct _tds__GetCapabilitiesResponse *Response;
    
    if(NULL == (req = (struct _tds__GetCapabilities *)calloc(1,sizeof(struct _tds__GetCapabilities))))
    {
        printf("calloc is error \n");
        ret = -1;
        return ret;
    }else{
        req->__sizeCategory = 1;
        req->Category = (enum tt__CapabilityCategory *)soap_malloc(soap, sizeof(int));
        *(req->Category) = (enum tt__CapabilityCategory)5; //5表示：tt__CapabilityCategory__Media

        ONVIF_SetAuthInfo(soap,"admin","hk123456");  //鉴权，输入摄像头的用户名、密码
        ret = soap_call___tds__GetCapabilities(soap, sercer_addr, NULL,req, Response);
        if(soap->error){ 
            ret = -1;
            printf("soap error: %d, %s, %s\n", soap->error, *soap_faultcode(soap), *soap_faultstring(soap));
            return ret;
        }else{;
            if(NULL != Response->Capabilities)
            {
                if (Response->Capabilities->Media != NULL){
                    if (Response->Capabilities->Media->XAddr != NULL){
                        printf(" media_addr: %s \n", Response->Capabilities->Media->XAddr); 
                    }
                }
            }
        }
    }

    if(NULL != req)
    {
        free(req);
        req = NULL;
    }

    ONVIF_soap_delete(soap);
    return ret;
}

在编译之前要把：stdsoap2.c  soapC.c  md5.c dom.c mecevp.c smdevp.c threads.c wsaapi.c wsseapi.c soapClient.c   把这些.c 还有有些配套的.h  拷贝到当前工作目录下。

如果出现以下错误要在编译的时候加：-DWITH_OPENSSL

/tmp/cccao7U5.o：在函数‘soap_mec_init’中：
mecevp.c:(.text+0xe)：对‘soap_ssl_init’未定义的引用
/tmp/ccV2yl3Q.o：在函数‘soap_smd_init’中：
smdevp.c:(.text+0x24c)：对‘soap_ssl_init’未定义的引用

编译：gcc -o test get_GetCapabilities_test.c stdsoap2.c soapC.c md5.c dom.c mecevp.c smdevp.c threads.c wsaapi.c wsseapi.c soapClient.c -I import/ -DWITH_OPENSSL -lssl -lcrypto -ldl 

结果：成功得到我们想要的媒体地址