Struct RbResponse 

#[repr(C)]
pub struct RbResponse {
    pub error_code: u32,
    pub len: u32,
    pub capacity: u32,
    pub data: *mut c_void,
}

FFI buffer for binary transport responses

Similar to FfiBuffer but designed specifically for binary struct responses. The response data is a raw C struct that can be cast directly by the host.

Memory Layout

+------------+--------+----------+------------+
| error_code |  len   | capacity |    data    |
|   (u32)    | (u32)  |  (u32)   | (*mut u8)  |
+------------+--------+----------+------------+

Usage

• error_code == 0: Success, data points to response struct
• error_code != 0: Error, data may point to error message

Fields

error_code: u32

Error code (0 = success)

len: u32

Size of response data in bytes

capacity: u32

Allocation capacity

data: *mut c_void

Pointer to response data (or error message)

Implementations

impl RbResponse

pub fn success<T: Sized>(value: T) -> Self

Create a successful response with struct data

Safety

The type T must be #[repr(C)] and safe to transmit across FFI.

pub fn error(code: u32, message: &str) -> Self

Create an error response

pub fn empty() -> Self

Create an empty response (for invalid calls)

pub fn is_error(&self) -> bool

Check if this response indicates an error

pub unsafe fn free(&mut self)

Free the response buffer

Safety

• Must only be called once
• Must only be called on responses created by Rust
• For success responses, the original type’s size must match len

pub unsafe fn as_ref<T: Sized>(&self) -> Option<&T>

Get the response data as a typed reference

Safety

• Response must be successful (error_code == 0)
• Type T must match the type used to create the response
• T must be #[repr(C)]

Trait Implementations

impl Debug for RbResponse

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for RbResponse

fn default() -> Self

Returns the “default value” for a type.

impl Send for RbResponse