servicepoint-binding-c/src/commands/generic_command.rs
2025-05-07 08:53:49 +02:00

293 lines
10 KiB
Rust

use crate::mem::{
heap_clone, heap_drop, heap_move_nonnull, heap_move_ok, heap_remove,
};
use servicepoint::{
BitVecCommand, BitmapCommand, BrightnessGridCommand, CharGridCommand,
ClearCommand, Cp437GridCommand, FadeOutCommand, GlobalBrightnessCommand,
HardResetCommand, Packet, TypedCommand,
};
use std::ptr::{null_mut, NonNull};
/// Pointer to one of the available command structs.
#[repr(C)]
#[allow(missing_docs)]
pub union CommandUnion {
pub null: *mut u8,
pub bitmap: NonNull<BitmapCommand>,
pub bitvec: NonNull<BitVecCommand>,
pub brightness_grid: NonNull<BrightnessGridCommand>,
pub char_grid: NonNull<CharGridCommand>,
pub cp437_grid: NonNull<Cp437GridCommand>,
pub global_brightness: NonNull<GlobalBrightnessCommand>,
pub clear: NonNull<ClearCommand>,
#[allow(deprecated)]
pub bitmap_legacy: NonNull<servicepoint::BitmapLegacyCommand>,
pub hard_reset: NonNull<HardResetCommand>,
pub fade_out: NonNull<FadeOutCommand>,
}
/// Specifies the kind of command struct.
///
/// This is _not_ equivalent to the [servicepoint::CommandCode]s.
#[repr(u8)]
#[allow(missing_docs)]
pub enum CommandTag {
Invalid = 0,
Bitmap,
BitVec,
BrightnessGrid,
CharGrid,
Cp437Grid,
GlobalBrightness,
Clear,
HardReset,
FadeOut,
BitmapLegacy,
}
/// This struct represents a pointer to one of the possible command structs.
///
/// Only ever access `data` with the correct data type as specified by `tag`!
///
/// Rust equivalent: [TypedCommand].
#[repr(C)]
pub struct SPCommand {
/// Specifies which kind of command struct is contained in `data`
pub tag: CommandTag,
/// The pointer to the command struct
pub data: CommandUnion,
}
impl SPCommand {
const INVALID: SPCommand = SPCommand {
tag: CommandTag::Invalid,
data: CommandUnion { null: null_mut() },
};
}
/// Tries to turn a [Packet] into a [SPCommand].
///
/// The packet is dropped in the process.
///
/// Returns: pointer to new [SPCommand] instance or NULL if parsing failed.
#[no_mangle]
pub unsafe extern "C" fn sp_cmd_generic_try_from_packet(
packet: NonNull<Packet>,
) -> *mut SPCommand {
let packet = *unsafe { Box::from_raw(packet.as_ptr()) };
heap_move_ok(servicepoint::TypedCommand::try_from(packet).map(|value| {
match value {
TypedCommand::Clear(clear) => SPCommand {
tag: CommandTag::Clear,
data: CommandUnion {
clear: heap_move_nonnull(clear),
},
},
TypedCommand::CharGrid(char_grid) => SPCommand {
tag: CommandTag::CharGrid,
data: CommandUnion {
char_grid: heap_move_nonnull(char_grid),
},
},
TypedCommand::Cp437Grid(cp437_grid) => SPCommand {
tag: CommandTag::Cp437Grid,
data: CommandUnion {
cp437_grid: heap_move_nonnull(cp437_grid),
},
},
TypedCommand::Bitmap(bitmap) => SPCommand {
tag: CommandTag::Bitmap,
data: CommandUnion {
bitmap: heap_move_nonnull(bitmap),
},
},
TypedCommand::Brightness(global_brightness) => SPCommand {
tag: CommandTag::GlobalBrightness,
data: CommandUnion {
global_brightness: heap_move_nonnull(global_brightness),
},
},
TypedCommand::BrightnessGrid(brightness_grid) => SPCommand {
tag: CommandTag::BrightnessGrid,
data: CommandUnion {
brightness_grid: heap_move_nonnull(brightness_grid),
},
},
TypedCommand::BitVec(bitvec) => SPCommand {
tag: CommandTag::BitVec,
data: CommandUnion {
bitvec: heap_move_nonnull(bitvec),
},
},
TypedCommand::HardReset(hard_reset) => SPCommand {
tag: CommandTag::HardReset,
data: CommandUnion {
hard_reset: heap_move_nonnull(hard_reset),
},
},
TypedCommand::FadeOut(fade_out) => SPCommand {
tag: CommandTag::FadeOut,
data: CommandUnion {
fade_out: heap_move_nonnull(fade_out),
},
},
#[allow(deprecated)]
TypedCommand::BitmapLegacy(bitmap_legacy) => SPCommand {
tag: CommandTag::BitmapLegacy,
data: CommandUnion {
bitmap_legacy: heap_move_nonnull(bitmap_legacy),
},
},
}
}))
}
/// Clones an [SPCommand] instance.
///
/// returns: a new [SPCommand] instance.
#[no_mangle]
pub unsafe extern "C" fn sp_cmd_generic_clone(command: SPCommand) -> SPCommand {
unsafe {
match command.tag {
CommandTag::Clear => SPCommand {
tag: CommandTag::Clear,
data: CommandUnion {
clear: heap_clone(command.data.clear),
},
},
CommandTag::CharGrid => SPCommand {
tag: CommandTag::CharGrid,
data: CommandUnion {
char_grid: heap_clone(command.data.char_grid),
},
},
CommandTag::Cp437Grid => SPCommand {
tag: CommandTag::Cp437Grid,
data: CommandUnion {
cp437_grid: heap_clone(command.data.cp437_grid),
},
},
CommandTag::Bitmap => SPCommand {
tag: CommandTag::Bitmap,
data: CommandUnion {
bitmap: heap_clone(command.data.bitmap),
},
},
CommandTag::GlobalBrightness => SPCommand {
tag: CommandTag::GlobalBrightness,
data: CommandUnion {
global_brightness: heap_clone(
command.data.global_brightness,
),
},
},
CommandTag::BrightnessGrid => SPCommand {
tag: CommandTag::BrightnessGrid,
data: CommandUnion {
brightness_grid: heap_clone(command.data.brightness_grid),
},
},
CommandTag::BitVec => SPCommand {
tag: CommandTag::BitVec,
data: CommandUnion {
bitvec: heap_clone(command.data.bitvec),
},
},
CommandTag::HardReset => SPCommand {
tag: CommandTag::HardReset,
data: CommandUnion {
hard_reset: heap_clone(command.data.hard_reset),
},
},
CommandTag::FadeOut => SPCommand {
tag: CommandTag::FadeOut,
data: CommandUnion {
fade_out: heap_clone(command.data.fade_out),
},
},
#[allow(deprecated)]
CommandTag::BitmapLegacy => SPCommand {
tag: CommandTag::BitmapLegacy,
data: CommandUnion {
bitmap_legacy: heap_clone(command.data.bitmap_legacy),
},
},
CommandTag::Invalid => SPCommand::INVALID,
}
}
}
/// Deallocates an [SPCommand].
///
/// # Examples
///
/// ```C
/// SPCommand c = sp_cmd_clear_into_generic(sp_cmd_clear_new());
/// sp_command_free(c);
/// ```
#[no_mangle]
pub unsafe extern "C" fn sp_cmd_generic_free(command: SPCommand) {
unsafe {
match command.tag {
CommandTag::Invalid => return,
CommandTag::Bitmap => heap_drop(command.data.bitmap),
CommandTag::BitVec => heap_drop(command.data.bitvec),
CommandTag::BrightnessGrid => {
heap_drop(command.data.brightness_grid)
}
CommandTag::CharGrid => heap_drop(command.data.char_grid),
CommandTag::Cp437Grid => heap_drop(command.data.cp437_grid),
CommandTag::GlobalBrightness => {
heap_drop(command.data.global_brightness)
}
CommandTag::Clear => heap_drop(command.data.clear),
CommandTag::HardReset => heap_drop(command.data.hard_reset),
CommandTag::FadeOut => heap_drop(command.data.fade_out),
CommandTag::BitmapLegacy => heap_drop(command.data.bitmap_legacy),
}
}
}
/// Tries to turn a [SPCommand] into a [Packet].
/// The [SPCommand] gets consumed.
///
/// Returns tag [CommandTag::Invalid] in case of an error.
#[no_mangle]
pub unsafe extern "C" fn sp_cmd_generic_into_packet(
command: SPCommand,
) -> *mut Packet {
match command.tag {
CommandTag::Invalid => null_mut(),
CommandTag::Bitmap => {
heap_move_ok(unsafe { heap_remove(command.data.bitmap).try_into() })
}
CommandTag::BitVec => {
heap_move_ok(unsafe { heap_remove(command.data.bitvec).try_into() })
}
CommandTag::BrightnessGrid => heap_move_ok(unsafe {
heap_remove(command.data.brightness_grid).try_into()
}),
CommandTag::CharGrid => heap_move_ok(unsafe {
heap_remove(command.data.char_grid).try_into()
}),
CommandTag::Cp437Grid => heap_move_ok(unsafe {
heap_remove(command.data.cp437_grid).try_into()
}),
CommandTag::GlobalBrightness => heap_move_ok(unsafe {
heap_remove(command.data.global_brightness).try_into()
}),
CommandTag::Clear => {
heap_move_ok(unsafe { heap_remove(command.data.clear).try_into() })
}
CommandTag::HardReset => heap_move_ok(unsafe {
heap_remove(command.data.hard_reset).try_into()
}),
CommandTag::FadeOut => heap_move_ok(unsafe {
heap_remove(command.data.fade_out).try_into()
}),
CommandTag::BitmapLegacy => heap_move_ok(unsafe {
heap_remove(command.data.bitmap_legacy).try_into()
}),
}
}