Method try_push

nodedb-bridge/src/buffer.rs:157–195

Try to enqueue a value. Returns `Err(BridgeError::Full)` if the ring is full, or `Err(BridgeError::Disconnected)` if the consumer was dropped.

(&mut self, value: T)

    /// Try to enqueue a value. Returns `Err(BridgeError::Full)` if the ring is full,
    /// or `Err(BridgeError::Disconnected)` if the consumer was dropped.
    pub fn try_push(&mut self, value: T) -> Result<()> {
        if self.shared.disconnected.load(Ordering::Relaxed) {
            return Err(BridgeError::Disconnected { side: "consumer" });
        }

        let tail = self.shared.tail.value.load(Ordering::Relaxed);

        // Fast path: check cached head first (avoids atomic load).
        if tail.wrapping_sub(self.cached_head) >= self.shared.capacity as u64 {
            // Slow path: refresh cached head from the atomic.
            self.cached_head = self.shared.head.value.load(Ordering::Acquire);

            if tail.wrapping_sub(self.cached_head) >= self.shared.capacity as u64 {
                self.shared.metrics.record_full();
                return Err(BridgeError::Full {
                    capacity: self.shared.capacity,
                    pending: (tail.wrapping_sub(self.cached_head)) as usize,
                });
            }
        }

        let idx = (tail as usize) & self.shared.mask;

        // SAFETY: We have exclusive write access to this slot because:
        // 1. We are the only producer (SPSC).
        // 2. The consumer's head hasn't reached this slot yet (checked above).
        unsafe {
            (*self.shared.slots[idx].get()) = Some(value);
        }

        // Make the value visible to the consumer.
        self.shared
            .tail
            .value
            .store(tail.wrapping_add(1), Ordering::Release);

        self.shared.metrics.record_push();
        Ok(())
    }

    /// Returns the current queue utilization as a percentage (0-100).
    pub fn utilization(&self) -> u8 {