C++ SrsAmf0Object::total_size方法代码示例

// user scenario: coding and decoding with amf0
VOID TEST(AMF0Test, ScenarioMain)
{
    // coded amf0 object
    int nb_bytes = 0;
    char* bytes = NULL;
    
    // coding data to binaries by amf0
    // for example, send connect app response to client.
    if (true) {
        // props: object
        //        fmsVer: string
        //        capabilities: number
        //        mode: number
        // info: object
        //         level: string
        //        code: string
        //        descrption: string
        //        objectEncoding: number
        //        data: array
        //                version: string
        //                srs_sig: string
        SrsAmf0Object* props = SrsAmf0Any::object();
        SrsAutoFree(SrsAmf0Object, props);
        props->set("fmsVer", SrsAmf0Any::str("FMS/3,5,3,888"));
        props->set("capabilities", SrsAmf0Any::number(253));
        props->set("mode", SrsAmf0Any::number(123));
        
        SrsAmf0Object* info = SrsAmf0Any::object();
        SrsAutoFree(SrsAmf0Object, info);
        info->set("level", SrsAmf0Any::str("info"));
        info->set("code", SrsAmf0Any::str("NetStream.Connnect.Success"));
        info->set("descrption", SrsAmf0Any::str("connected"));
        info->set("objectEncoding", SrsAmf0Any::number(3));
        
        SrsAmf0EcmaArray* data = SrsAmf0Any::ecma_array();
        info->set("data", data);
        data->set("version", SrsAmf0Any::str("FMS/3,5,3,888"));
        data->set("srs_sig", SrsAmf0Any::str("srs"));
        
        // buf store the serialized props/info
        nb_bytes = props->total_size() + info->total_size();
        ASSERT_GT(nb_bytes, 0);
        bytes = new char[nb_bytes];
        
        // use SrsStream to write props/info to binary buf.
        SrsStream s;
        EXPECT_EQ(ERROR_SUCCESS, s.initialize(bytes, nb_bytes));
        EXPECT_EQ(ERROR_SUCCESS, props->write(&s));
        EXPECT_EQ(ERROR_SUCCESS, info->write(&s));
        EXPECT_TRUE(s.empty());
        
        // now, user can use the buf
        EXPECT_EQ(0x03, bytes[0]);
        EXPECT_EQ(0x09, bytes[nb_bytes - 1]);
    }
    SrsAutoFree(char, bytes);
    
    // decoding amf0 object from bytes
    // when user know the schema
    if (true) {
        ASSERT_TRUE(NULL != bytes);
        
        // use SrsStream to assist amf0 object to read from bytes.
        SrsStream s;
        EXPECT_EQ(ERROR_SUCCESS, s.initialize(bytes, nb_bytes));
        
        // decoding
        // if user know the schema, for instance, it's an amf0 object,
        // user can use specified object to decoding.
        SrsAmf0Object* props = SrsAmf0Any::object();
        SrsAutoFree(SrsAmf0Object, props);
        EXPECT_EQ(ERROR_SUCCESS, props->read(&s));
        
        // user can use specified object to decoding.
        SrsAmf0Object* info = SrsAmf0Any::object();
        SrsAutoFree(SrsAmf0Object, info);
        EXPECT_EQ(ERROR_SUCCESS, info->read(&s));
        
        // use the decoded data.
        SrsAmf0Any* prop = NULL;
        
        // if user requires specified property, use ensure of amf0 object
        EXPECT_TRUE(NULL != (prop = props->ensure_property_string("fmsVer")));
        // the property can assert to string.
        ASSERT_TRUE(prop->is_string());
        // get the prop string value.
        EXPECT_STREQ("FMS/3,5,3,888", prop->to_str().c_str());
        
        // get other type property value
        EXPECT_TRUE(NULL != (prop = info->get_property("data")));
        // we cannot assert the property is ecma array
        if (prop->is_ecma_array()) {
            SrsAmf0EcmaArray* data = prop->to_ecma_array();
            // it must be a ecma array.
            ASSERT_TRUE(NULL != data);
            
            // get property of array
            EXPECT_TRUE(NULL != (prop = data->ensure_property_string("srs_sig")));
            ASSERT_TRUE(prop->is_string());
//.........这里部分代码省略.........

int SrsFlvSegment::write_metadata(SrsSharedPtrMessage* metadata)
{
    int ret = ERROR_SUCCESS;

    if (duration_offset || filesize_offset) {
        return ret;
    }

    SrsBuffer stream;
    if ((ret = stream.initialize(metadata->payload, metadata->size)) != ERROR_SUCCESS) {
        return ret;
    }

    SrsAmf0Any* name = SrsAmf0Any::str();
    SrsAutoFree(SrsAmf0Any, name);
    if ((ret = name->read(&stream)) != ERROR_SUCCESS) {
        return ret;
    }

    SrsAmf0Object* obj = SrsAmf0Any::object();
    SrsAutoFree(SrsAmf0Object, obj);
    if ((ret = obj->read(&stream)) != ERROR_SUCCESS) {
        return ret;
    }

    // remove duration and filesize.
    obj->set("filesize", NULL);
    obj->set("duration", NULL);

    // add properties.
    obj->set("service", SrsAmf0Any::str(RTMP_SIG_SRS_SERVER));
    obj->set("filesize", SrsAmf0Any::number(0));
    obj->set("duration", SrsAmf0Any::number(0));
    
    int size = name->total_size() + obj->total_size();
    char* payload = new char[size];
    SrsAutoFreeA(char, payload);

    // 11B flv header, 3B object EOF, 8B number value, 1B number flag.
    duration_offset = fs->tellg() + size + 11 - SrsAmf0Size::object_eof() - SrsAmf0Size::number();
    // 2B string flag, 8B number value, 8B string 'duration', 1B number flag
    filesize_offset = duration_offset - SrsAmf0Size::utf8("duration") - SrsAmf0Size::number();

    // convert metadata to bytes.
    if ((ret = stream.initialize(payload, size)) != ERROR_SUCCESS) {
        return ret;
    }
    if ((ret = name->write(&stream)) != ERROR_SUCCESS) {
        return ret;
    }
    if ((ret = obj->write(&stream)) != ERROR_SUCCESS) {
        return ret;
    }
    
    // to flv file.
    if ((ret = enc->write_metadata(18, payload, size)) != ERROR_SUCCESS) {
        return ret;
    }
    
    return ret;
}