7.3. Generic parameters Arg

7.3.2. Overview

2. arg can hold a value of any type in it. The types supported by arg are: int, float, pointer, string, null, bytes. 1.

3. arg can be put into an object and the value of arg can be accessed directly in the python script.

The data type of a generic argument is Arg.

    Arg* next;
    uint32_t size;
    uint8_t type;
    Hash name_hash;
    uint8_t content[];

The generic arguments internally include header information ( size, type, name_hash ), the data body (content), and a pointer (next) used to form the chain.

7.3.4. Creating and destroying generic arguments

• Creating a new generic argument

Creates a new generic argument from the heap and returns a pointer to the generic argument.

**Note that newly created generic parameters need to be manually destroyed to reclaim memory. Constantly creating new generic parameters but not destroying them can lead to memory leaks. **

[Note] The following api requires a kernel version of at least v1.9.2

New arg The argument passed in is the value of arg.

• Destroy generic arguments.

void arg_deinit(Arg* self);

• Copy generic arguments

Use the following API to determine the current type of a generic argument.

ArgType arg_getType(Arg* self);

Use the following API to convert a generic argument to a basic type.

7.3.6. Important Notes

Direct use of the arg_new<Type>() api **is highly likely to cause **memory leaks or dangling references, resulting in fatal flaws.

Please develop under docker development environment to ensure sufficient unit testing and memory checking.

...
    /* Create a list object */
    PikaObj* list = newNormalObj(New_PikaStdData_List);
    PikaStdData_List___init__(list);
    /* Create arg with api of arg_new<type> */
    Arg* str_arg1 = arg_newStr("aaa");
    /* add to list object */
    PikaStdData_List_append(list, str_arg1);
    /* destroy arg */