swaitsandClaude Opus 4.6
3102fc747a
Implement full SSD1306 OLED display support: - Splash screen on boot (1.5s) with project name, version, board - Dashboard showing radio state, config, counters, RSSI/SNR - RSSI history sparkline (64-sample ring buffer, 2px-wide bars) - DisplayOn/DisplayOff host commands routed via dedicated channel - Pure render functions against generic DrawTarget (no hardware coupling) - Display on/off control bypasses radio task entirely Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
53 lines
1.5 KiB
Rust
53 lines
1.5 KiB
Rust
/// Macro to create a mutable reference to a statically allocated value
|
|
///
|
|
/// This macro returns a value with type `Option<&'static mut $ty>`.
|
|
/// `Some($expr)` will be returned the first time the macro is executed; further
|
|
/// calls will return `None`. To avoid `unwrap`ping a `None` variant the caller
|
|
/// must ensure that the macro is called from a function that's executed at most
|
|
/// once in the whole lifetime of the program.
|
|
///
|
|
/// # Example
|
|
///
|
|
/// ``` no_run
|
|
/// use xtensa_lx::singleton;
|
|
///
|
|
/// fn main() {
|
|
/// // OK if `main` is executed only once
|
|
/// let x: &'static mut bool = singleton!(: bool = false).unwrap();
|
|
///
|
|
/// let y = alias();
|
|
/// // BAD this second call to `alias` will definitively `panic!`
|
|
/// let y_alias = alias();
|
|
/// }
|
|
///
|
|
/// fn alias() -> &'static mut bool {
|
|
/// singleton!(: bool = false).unwrap()
|
|
/// }
|
|
/// ```
|
|
#[macro_export]
|
|
macro_rules! singleton {
|
|
(: $ty:ty = $expr:expr) => {
|
|
$crate::interrupt::free(|_| {
|
|
static mut VAR: Option<$ty> = None;
|
|
|
|
#[allow(unsafe_code)]
|
|
let used = unsafe { VAR.is_some() };
|
|
if used {
|
|
None
|
|
} else {
|
|
let expr = $expr;
|
|
|
|
#[allow(unsafe_code)]
|
|
unsafe {
|
|
VAR = Some(expr)
|
|
}
|
|
|
|
#[allow(unsafe_code)]
|
|
unsafe {
|
|
VAR.as_mut()
|
|
}
|
|
}
|
|
})
|
|
};
|
|
}
|