设备搜索：要访问一个IPC摄像头，或者说要调用IPC摄像头提供的WEB服务接口，就要先知道其IP地址，这就是设备发现的过程，或者叫设备搜索的过程。IPC摄像头用的是239.255.255.250(端口3702)，所以设备搜索的原理是，只要在设备上服务器监听239.255.255.250的3702端口。ONVIF规范并没有自己定义服务设备发现框架，而是复用了已经很成熟的WS-Discovery标准，根据.wsdl的文件，用gsoap产生框架代码，调用其产生的函数接口去实现设备的搜索。

1、gsoap框架代码：https://blog.csdn.net/weixin_42432281/article/details/84818575

2、上一部如果完成，就直接略过，将安装的gsoap-2.8\gsoap目录下的两个文件：stdsoap2.c、stdsoap2.h拷贝到你工作目录下

3、注释stdsoap2.c如下代码：不注释的话会在编译运行的时候产生log日志，最后会发现磁盘已满的现象。

/*

#ifdef SOAP_DEBUG

#ifdef TANDEM_NONSTOP

soap_set_test_logfile(soap, "TESTLOG");

soap_set_sent_logfile(soap, "SENTLOG");

soap_set_recv_logfile(soap, "RECVLOG");

#else

soap_set_test_logfile(soap, "TEST.log");

soap_set_sent_logfile(soap, "SENT.log");

soap_set_recv_logfile(soap, "RECV.log");

#endif

#endif

*/

和修改

if (/*s == r || *r || */n < -128 || n > 127)

4、将安装的gsoap2.8目录下的import目录，拷贝到生成.c、.h的工作的文件夹里，cp gsoap-2.8/gsoap/import ./  ,REAMOD.txt是我写的记录文档，不必在意，其他的文件都拷贝到这个目录下

5、设备搜索的代码：我是直接copy别人的代码，做了一下修改(https://blog.csdn.net/saloon_yuan/article/details/27524875)

#include #include#include#include"soapH.h"#include"stdsoap2.h"#include"soapStub.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, inttimeout)

{struct soap *soap = NULL; //soap环境变量

unsigned char macaddr[6];char _HwId[1024];

unsignedintFlagrand;

soap=soap_new();if(soap ==NULL)

{

printf("[%d]soap = NULL\n", __LINE__);returnNULL;

}

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;returnsoap;

}//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

}intONVIF_ClientDiscovery()

{int FoundDevNo = 0;int retval =SOAP_OK;

wsdd__ProbeType req;//用于发送Probe消息

struct __wsdd__ProbeMatches resp; //用于接收Probe应答

wsdd__ScopesType sScope;structSOAP_ENV__Header header;struct soap*soap;const char *was_To = "urn:schemas-xmlsoap-org:ws:2005:04:discovery";const char *was_Action = "http://schemas.xmlsoap.org/ws/2005/04/discovery/Probe";//IP Adress and PortNo, broadCast

const char *soap_endpoint = "soap.udp://239.255.255.250:3702/"; //设备上服务器监听239.255.255.250的3702端口//Create new soap object with info

soap = ONVIF_Initsoap(&header, was_To, was_Action, 10);

soap_default_SOAP_ENV__Header(soap,&header);

soap->header = &header;

soap_default_wsdd__ScopesType(soap,&sScope); //设置寻找设备的范围

sScope.__item =NULL;

soap_default_wsdd__ProbeType(soap,&req); //设置寻找设备的类型

req.Scopes = &sScope;

req.Types= NULL; //"dn:NetworkVideoTransmitter";//sent the message broadcast and wait

retval = soap_send___wsdd__Probe(soap, soap_endpoint, NULL, &req); //向组播地址广播Probe消息

while(retval ==SOAP_OK)

{

printf("**************1**************\n");

retval= soap_recv___wsdd__ProbeMatches(soap, &resp);if(retval ==SOAP_OK)

{if(soap->error)

{

printf("[%d]:recv soap error :%d, %s, %s\n", __LINE__, soap->error, *soap_faultcode(soap), *soap_faultstring(soap));

retval= soap->error;

}else //we find a device

{

FoundDevNo++;if(resp.wsdd__ProbeMatches->ProbeMatch != NULL && resp.wsdd__ProbeMatches->ProbeMatch->XAddrs !=NULL)

{

printf("***** No %d Devices Information *****\n", FoundDevNo);

printf("Device Service Address : %s\r\n", resp.wsdd__ProbeMatches->ProbeMatch->XAddrs);

printf("Device EP Address : %s\r\n", resp.wsdd__ProbeMatches->ProbeMatch->wsa__EndpointReference.Address);

printf("Device Type : %s\r\n", resp.wsdd__ProbeMatches->ProbeMatch->Types);

printf("Device Metadata Version: %d\r\n", resp.wsdd__ProbeMatches->ProbeMatch->MetadataVersion);

printf("[%d]*********************************\n", __LINE__);

}

}

}else if(soap->error)

{if(FoundDevNo == 0)

{

printf("No Device found!\n");

retval= soap->error;

}else{

printf("Search end! Find %d Device! \n", FoundDevNo);

retval= 0;

}break;

}

}//释放函数

ONVIF_soap_delete(soap);returnretval;

}int main(int argc, char *argv[])

{if(ONVIF_ClientDiscovery() != 0)

{

printf("discover failed! \n");return -1;

}return 0;

}

6、在编译时如果出现：对‘namespaces’未定义的引用，那是你在程序中没有加 #include "wsdd.nsmap" ，这个头文件，加上即可。

7、编译，生成可执行文件test：gcc -o test search_test.c  stdsoap2.c  soapC.c  soapClient.c -I import/

8、运行test： ./test

设备搜索已完成！

设备搜索的主要目的是获取他服务器的地址：http://172.168.0.216/onvif/device_service，为下一步获取能力做准备。