NanoPB 帮助！编码嵌套的重复项，但不确定我是否正确定义了架构

如何解决NanoPB 帮助！编码嵌套的重复项，但不确定我是否正确定义了架构

我正在定义电池组的故障。 包由一个或多个模块组成。 模块由6个Cell组成。

我已经能够得到包信息减去重复的模块。我相信我重复的模块现在正在编码但出现错误： Decoding failed: parent stream too short

目前我的原型是这样的

    syntax = "proto2";
    
    package TeslaBMS;
    
    message Pack { 
      required int32 numberOfModules = 2;
      required float currentVoltage = 3;
      required float averagePacktemp = 4;
      repeated Module modules = 5;
    
        message Module {
          required int32 id = 1;
          required float moduleVoltage = 2;
          required float moduleTemp = 3;
          required float lowestCellVolt = 4;
          required float highestCellVolt = 5;
      //   repeated Cell cells = 6;
    
      //  message Cell{
      //       required int32 cellId = 1;
      //       required float cellVolt = 2;
      //       required string balanceState = 3;
      //  }
    
      }
    }

产生这些结构定义

/* Struct definitions */
typedef struct _TeslaBMS_Pack {
    int32_t numberOfModules;
    float currentVoltage;
    float averagePacktemp;
    pb_callback_t modules;
} TeslaBMS_Pack;

typedef struct _TeslaBMS_Pack_Module {
    int32_t id;
    float moduleVoltage;
    float moduleTemp;
    float lowestCellVolt;
    float highestCellVolt;
} TeslaBMS_Pack_Module;

我创建了一个 typedef 结构来保存一个模块数组

typedef struct{
    TeslaBMS_Pack_Module modarr[MAX_MODULE_ADDR];
    int listSize = 0;
}
ModuleList;

这些是一些构建模块数组的辅助函数 modulelist_add_module 用于解码，module_array_maker 用于编码

以下是我根据我能找到的示例进行编码/解码的内容。

编码：

void encoder(){
    // Setup pack message
    TeslaBMS_Pack mypack = TeslaBMS_Pack_init_zero;
    
    // stream to write buffer
    pb_ostream_t stream = pb_ostream_from_buffer(buffer,sizeof(buffer));

    // set deffinitions     
    mypack.averagePacktemp = bms.getAvgTemperature();
    mypack.currentVoltage = bms.getPackVoltage();
    mypack.numberOfModules = bms.getNumOfModules();

    ModuleList modArr;
    module_array_maker(&modArr);

      // set the arg to data needed
    mypack.modules.arg = &modArr;

      // encode the modules
    mypack.modules.funcs.encode = modules_encode;

      //encode the pack
    status = pb_encode(&stream,TeslaBMS_Pack_fields,&mypack);
    message_length = stream.bytes_written;
        
        if (!status) printf("Encoding failed: %s\n",PB_GET_ERROR(&stream));
}     

为重复模块字段编码回调

bool modules_encode(pb_ostream_t *stream,const pb_field_iter_t *field,void * const *arg)
{    
    ModuleList *source = (ModuleList*)(*arg);

    for(int i=0; i<bms.getNumOfModules();i++)
    {
        printf(" \n Mod %i is at %f \n",(int)source->modarr[i].id,source->modarr[i].moduleVoltage);
        if (!pb_encode_tag_for_field(stream,field))
        {
            const char * error = PB_GET_ERROR(stream);
            printf("encode_modules error: %s",error);
            return false;
        }
        if (!(stream,TeslaBMS_Pack_Module_fields,&source->modarr[i]))
        {
            const char * error = PB_GET_ERROR(stream);
            printf("SimpleMessage_encode_numbers error: %s",error);
            return false;
        }
    }
    return true;
}

解码：

void decode(){
    /* Allocate space for the decoded message. */
    TeslaBMS_Pack myPack = TeslaBMS_Pack_init_zero;
    
    /* Create a stream that reads from the buffer. */
    
    ModuleList modArr;
    module_array_maker(&modArr);
    myPack.modules.arg = &modArr;
    myPack.modules.funcs.decode = modules_decode;

    pb_istream_t stream = pb_istream_from_buffer(buffer,message_length);
    /* Now we are ready to decode the message. */
    status = pb_decode(&stream,&myPack);
    
    /* Check for errors... */
    if (!status)
    {
        printf("Decoding failed: %s\n",PB_GET_ERROR(&stream));
    }
    else
    {
        /* Print the data contained in the message. */
        printf("\n********MESSAGE FROM NANOPB!*********\n");
        // printf("Number Of Modules in Pack: ",myPack.numberOfModules);
        printf("Pack Voltage: %.3f\n",myPack.currentVoltage);
        printf("Average Temp: %.3f\n",myPack.averagePacktemp);
        printf("Number of modules: %i\n",(int)myPack.numberOfModules);
        for (size_t i = 0; i < myPack.numberOfModules ; i++)
        {
            printf("\n    ************  Module %i  ************\n",modArr.modarr[i].id);
            printf("       Voltage: %.3f Temperature: %.3f \n",modArr.modarr[i].moduleVoltage,modArr.modarr[i].moduleTemp);
        }        
        printf("********MESSAGE FROM NANOPB!*********\n");
    }
}

模块的解码回调

bool modules_decode(pb_istream_t *istream,const pb_field_t *field,void **arg){
    ModuleList * dest = (ModuleList*)(*arg);

    TeslaBMS_Pack_Module module;
    if(!pb_decode(istream,&module)){
        const char * error = PB_GET_ERROR(istream);
        printf("module_decode error: %s",error);
        return false;
    }
    
    modulelist_add_module(dest,module);
    return true;
}