servicepoint-binding-c/src/packet.rs
Vinzenz Schroeter 3589a90385
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Rust / build (pull_request) Failing after 3m9s
add functions to convert containers directly into packet
2025-04-12 22:13:29 +02:00

129 lines
3.5 KiB
Rust

use crate::{heap_drop, heap_move, heap_move_nonnull, heap_remove, ByteSlice};
use servicepoint::{CommandCode, Header, Packet, TypedCommand};
use std::ptr::NonNull;
/// Turns a [TypedCommand] into a [Packet].
/// The [TypedCommand] gets consumed.
///
/// Returns NULL in case of an error.
#[no_mangle]
pub unsafe extern "C" fn sp_packet_from_command(
command: NonNull<TypedCommand>,
) -> *mut Packet {
let command = unsafe { heap_remove(command) };
if let Ok(packet) = command.try_into() {
heap_move(packet)
} else {
std::ptr::null_mut()
}
}
/// Tries to load a [Packet] from the passed array with the specified length.
///
/// returns: NULL in case of an error, pointer to the allocated packet otherwise
#[no_mangle]
pub unsafe extern "C" fn sp_packet_try_load(data: ByteSlice) -> *mut Packet {
let data = unsafe { data.as_slice() };
match servicepoint::Packet::try_from(data) {
Err(_) => std::ptr::null_mut(),
Ok(packet) => heap_move(packet),
}
}
/// Creates a raw [Packet] from parts.
///
/// returns: new instance. Will never return null.
#[no_mangle]
pub unsafe extern "C" fn sp_packet_from_parts(
header: Header,
payload: *const ByteSlice,
) -> NonNull<Packet> {
let payload = if payload.is_null() {
vec![]
} else {
let payload = unsafe { (*payload).as_slice() };
Vec::from(payload)
};
heap_move_nonnull(Packet { header, payload })
}
/// Returns a pointer to the header field of the provided packet.
///
/// The returned header can be changed and will be valid for the lifetime of the packet.
#[no_mangle]
pub unsafe extern "C" fn sp_packet_get_header(
packet: NonNull<Packet>,
) -> NonNull<Header> {
NonNull::from(&mut unsafe { (*packet.as_ptr()).header })
}
/// Returns a pointer to the current payload of the provided packet.
///
/// The returned memory can be changed and will be valid until a new payload is set.
#[no_mangle]
pub unsafe extern "C" fn sp_packet_get_payload(
packet: NonNull<Packet>,
) -> ByteSlice {
unsafe { ByteSlice::from_slice(&mut (*packet.as_ptr()).payload) }
}
/// Sets the payload of the provided packet to the provided data.
///
/// This makes previous payload pointers invalid.
#[no_mangle]
pub unsafe extern "C" fn sp_packet_set_payload(
packet: NonNull<Packet>,
data: ByteSlice,
) {
unsafe { (*packet.as_ptr()).payload = data.as_slice().to_vec() }
}
/// Serialize the packet into the provided buffer.
///
/// # Panics
///
/// - if the buffer is not big enough to hold header+payload.
#[no_mangle]
pub unsafe extern "C" fn sp_packet_serialize_to(
packet: NonNull<Packet>,
mut buffer: ByteSlice,
) {
unsafe {
packet.as_ref().serialize_to(buffer.as_slice_mut());
}
}
/// Clones a [Packet].
#[no_mangle]
pub unsafe extern "C" fn sp_packet_clone(
packet: NonNull<Packet>,
) -> NonNull<Packet> {
heap_move_nonnull(unsafe { packet.as_ref().clone() })
}
/// Deallocates a [Packet].
#[no_mangle]
pub unsafe extern "C" fn sp_packet_free(packet: NonNull<Packet>) {
unsafe { heap_drop(packet) }
}
/// Converts u16 into [CommandCode].
///
/// If the provided value is not valid, false is returned and result is not changed.
#[no_mangle]
pub unsafe extern "C" fn sp_u16_to_command_code(
code: u16,
result: *mut CommandCode,
) -> bool {
match CommandCode::try_from(code) {
Ok(code) => {
unsafe {
*result = code;
}
true
}
Err(_) => false,
}
}