amberjs 1.16.1

// 零拷贝数据传输优化模块
// 通过引用传递和内存映射实现高性能数据传输

use crate::lock_free_temp::{AtomicStats, LockFreeBufferPool, LockFreeCounter};
use std::collections::{BTreeMap, HashMap};
use std::sync::{Arc, Mutex};
use std::fs::File;
use tokio::io::{AsyncSeekExt, AsyncWriteExt};
use std::time::Instant;
use std::sync::atomic::{AtomicUsize, Ordering};
use std::num::NonZeroUsize;
use std::marker::PhantomData;
use tempfile::TempDir;

/// 零拷贝缓冲区
/// 包装一个字节切片，允许零拷贝传递
#[derive(Debug, Clone)]
#[allow(dead_code)]
pub struct ZeroCopyBuffer {
    data: Arc<[u8]>,
}
#[allow(dead_code)]
impl ZeroCopyBuffer {
    /// 从字节向量创建零拷贝缓冲区
    pub fn new(data: Vec<u8>) -> Self {
        Self {
            data: Arc::from(data.into_boxed_slice()),
        }
    }
    /// 从字节切片创建零拷贝缓冲区
    pub fn from_slice(data: &[u8]) -> Self {
        Self {
            data: Arc::from(data.to_vec().into_boxed_slice()),
        }
    }
    /// 获取数据长度
    pub fn len(&self) -> usize {
        self.data.len()
    }
    /// 检查是否为空
    pub fn is_empty(&self) -> bool {
        self.data.is_empty()
    }
    /// 获取数据引用（零拷贝）
    pub fn as_slice(&self) -> &[u8] {
        &self.data
    }
    /// 转换为字节向量（需要分配）
    pub fn to_vec(&self) -> Vec<u8> {
        self.data.to_vec()
    }
    /// 克隆缓冲区（共享内部数据）
    pub fn duplicate(&self) -> Self {
        Self {
            data: Arc::clone(&self.data),
        }
    }
}
/// 零拷贝数据传输通道
#[derive(Debug)]
#[allow(dead_code)]
pub struct ZeroCopyChannel<T> {
    sender: crossbeam::channel::Sender<T>,
    receiver: crossbeam::channel::Receiver<T>,
    _phantom: PhantomData<T>,
}
#[allow(dead_code)]
impl<T> ZeroCopyChannel<T> {
    /// 创建新的零拷贝通道
    pub fn new(capacity: usize) -> Self {
        let (sender, receiver) = crossbeam::channel::bounded(capacity);
        Self {
            sender,
            receiver,
            _phantom: PhantomData,
        }
    }
    /// 发送数据（零拷贝）
    pub fn send(&self, data: T) -> Result<(), crossbeam::channel::SendError<T>> {
        self.sender.send(data)
    }
    /// 接收数据（零拷贝）
    pub fn recv(&self) -> Result<T, crossbeam::channel::RecvError> {
        self.receiver.recv()
    }
    /// 尝试发送
    pub fn try_send(&self, data: T) -> Result<(), crossbeam::channel::TrySendError<T>> {
        self.sender.try_send(data)
    }
    /// 尝试接收
    pub fn try_recv(&self) -> Result<T, crossbeam::channel::TryRecvError> {
        self.receiver.try_recv()
    }
}
/// 零拷贝文件读取器
#[derive(Debug)]
#[allow(dead_code)]
pub struct ZeroCopyFileReader {
    file: File,
}
#[allow(dead_code)]
impl ZeroCopyFileReader {
    /// 创建新的零拷贝文件读取器
    pub async fn new(path: &str) -> Result<Self, std::io::Error> {
        let file: _ = tokio::fs::File::open(path).await?;
        Ok(Self { file })
    }
    /// 读取文件到零拷贝缓冲区
    pub async fn read_to_buffer(&mut self) -> Result<ZeroCopyBuffer, std::io::Error> {
        let metadata: _ = self.file.metadata().await?;
        let size: _ = metadata.len() as usize;
        let mut buffer = vec![0u8; size];
        self.file.read_exact(&mut buffer).await?;
        Ok(ZeroCopyBuffer::new(buffer))
    }
    /// 读取文件的部分内容到零拷贝缓冲区
    pub async fn read_partial(&mut self, offset: u64, length: usize) -> Result<ZeroCopyBuffer, std::io::Error> {
        self.file.seek(std::io::SeekFrom::Start(offset)).await?;
        let mut buffer = vec![0u8; length];
        self.file.read_exact(&mut buffer).await?;
        Ok(ZeroCopyBuffer::new(buffer))
    }
}
/// 零拷贝文件写入器
#[derive(Debug)]
#[allow(dead_code)]
pub struct ZeroCopyFileWriter {
    file: File,
}
#[allow(dead_code)]
impl ZeroCopyFileWriter {
    /// 创建新的零拷贝文件写入器
    pub async fn new(path: &str) -> Result<Self, std::io::Error> {
        let file: _ = tokio::fs::File::create(path).await?;
        Ok(Self { file })
    }
    /// 从零拷贝缓冲区写入文件
    pub async fn write_from_buffer(&mut self, buffer: &ZeroCopyBuffer) -> Result<usize, std::io::Error> {
        // TODO: Remove unused import: use tokio::io::AsyncWriteExt;
        let bytes_written: _ = self.file.write(buffer.as_slice()).await?;
        self.file.flush().await?;
        Ok(bytes_written)
    }
    /// 追加零拷贝缓冲区内容到文件
    pub async fn append_from_buffer(&mut self, buffer: &ZeroCopyBuffer) -> Result<usize, std::io::Error> {
        // TODO: Remove unused import: use tokio::io::AsyncWriteExt;
        self.file.seek(std::io::SeekFrom::End(0)).await?;
        let bytes_written: _ = self.file.write(buffer.as_slice()).await?;
        self.file.flush().await?;
        Ok(bytes_written)
    }
}
/// 零拷贝内存映射文件
#[cfg(unix)]
// Removed unused imports: AsRawFd, RawFd
#[cfg(unix)]
#[allow(dead_code)]
pub struct MemoryMappedFile {
    mapping: Arc<memmap2::Mmap>,
    file: File,
}
#[cfg(unix)]
#[allow(dead_code)]
impl MemoryMappedFile {
    /// 创建内存映射文件
    pub async fn open(path: &str) -> Result<Self, std::io::Error> {
        let file: _ = OpenOptions::new()
            .read(true)
            .write(true)
            .create(true)
            .open(path)
            .await?;
        let mapping: _ = unsafe { memmap2::MmapOptions::new().map(&file)? };
        Ok(Self {
            mapping: Arc::new(Mutex::new(mapping)),
            file,
        })
    }
    /// 获取映射内存的切片（零拷贝）
    pub fn as_slice(&self) -> &[u8] {
        &self.mapping
    }
    /// 同步内存映射
    pub fn sync(&self) -> Result<(), std::io::Error> {
        // Arc<Mmap> dereference to &Mmap, then call sync
        let _: _ = Arc::as_ptr(&self.mapping);
        // 简化的实现：内存映射通常自动同步
        Ok(())
    }
    /// 分片读取大文件（零拷贝）
    pub fn read_chunk(&self, offset: usize, size: usize) -> Result<&[u8], std::io::Error> {
        if offset + size > self.mapping.len() {
            return Err(std::io::Error::new(
                std::io::ErrorKind::InvalidInput,
                "Offset + size exceeds file size"
            ));
        }
        Ok(&self.mapping[offset..offset + size])
    }
    /// 获取文件大小
    pub fn len(&self) -> usize {
        self.mapping.len()
    }
    /// 检查是否为空
    pub fn is_empty(&self) -> bool {
        self.mapping.is_empty()
    }
}
/// 零拷贝数据传输管理器
#[derive(Debug)]
#[allow(dead_code)]
pub struct ZeroCopyManager {
    buffer_pool: LockFreeBufferPool,
    channel_stats: Arc<AtomicStats>,
}
#[allow(dead_code)]
impl ZeroCopyManager {
    /// 创建新的零拷贝管理器
    pub fn new() -> Self {
        Self {
            buffer_pool: LockFreeBufferPool::new(),
            channel_stats: Arc::new(Mutex::new(AtomicStats::new())),
        }
    }
    /// 创建新的零拷贝通道
    pub fn create_channel<T>(&self, capacity: usize) -> ZeroCopyChannel<T> {
        self.channel_stats.record_operation("create_channel");
        ZeroCopyChannel::new(capacity)
    }
    /// 创建零拷贝缓冲区
    pub fn create_buffer(&self, data: Vec<u8>) -> ZeroCopyBuffer {
        self.buffer_pool.allocate(data.len());
        ZeroCopyBuffer::new(data)
    }
    /// 克隆缓冲区（共享内部数据，零拷贝）
    pub fn clone_buffer(&self, buffer: &ZeroCopyBuffer) -> ZeroCopyBuffer {
        self.channel_stats.record_operation("clone_buffer");
        buffer.duplicate()
    }
    /// 销毁缓冲区
    pub fn destroy_buffer(&self, _buffer: &ZeroCopyBuffer) {
        self.buffer_pool.deallocate(Vec::new());
    }
    /// 获取统计信息
    pub fn get_stats(&self) -> String {
        format!(
            "Buffer Pool: Active={}, Total Allocations={}, Available={}\nChannel Stats: {}",
            self.buffer_pool.active_count(),
            self.buffer_pool.total_allocations(),
            self.buffer_pool.available_count(),
            self.channel_stats.get_report()
        )
    }
    /// 重置统计信息
    pub fn reset_stats(&self) {
        // 注意：在实际实现中，需要在 AtomicStats 中添加重置方法
    }
}
/// 高性能零拷贝消息传递
#[derive(Debug)]
#[allow(dead_code)]
pub struct ZeroCopyMessage<T> {
    data: T,
    metadata: MessageMetadata,
}
#[derive(Debug, Clone)]
#[allow(dead_code)]
pub struct MessageMetadata {
    pub timestamp: std::time::Instant,
    pub size: usize,
    pub priority: u8,
}
#[allow(dead_code)]
impl<T> ZeroCopyMessage<T> {
    /// 创建新的零拷贝消息
    pub fn new(data: T) -> Self {
        Self {
            data,
            metadata: MessageMetadata {
                timestamp: std::time::Instant::now(),
                size: std::mem::size_of::<T>(),
                priority: 0,
            },
        }
    }
    /// 创建带优先级的高优先级消息
    pub fn new_with_priority(data: T, priority: u8) -> Self {
        Self {
            data,
            metadata: MessageMetadata {
                timestamp: std::time::Instant::now(),
                size: std::mem::size_of::<T>(),
                priority,
            },
        }
    }
    /// 获取消息数据引用
    pub fn get_data(&self) -> &T {
        &self.data
    }
    /// 获取消息元数据
    pub fn get_metadata(&self) -> &MessageMetadata {
        &self.metadata
    }
}
/// 零拷贝环形缓冲区
#[derive(Debug)]
#[allow(dead_code)]
pub struct ZeroCopyRingBuffer<T> {
    buffer: Vec<Option<T>>,
    write_index: LockFreeCounter,
    read_index: LockFreeCounter,
    capacity: usize,
}
#[allow(dead_code)]
impl<T> ZeroCopyRingBuffer<T> {
    /// 创建新的零拷贝环形缓冲区
    pub fn new(capacity: usize) -> Self {
        let mut buffer = Vec::with_capacity(capacity);
        for _ in 0..capacity {
            buffer.push(None);
        }
        Self {
            buffer,
            write_index: LockFreeCounter::new(0),
            read_index: LockFreeCounter::new(0),
            capacity,
        }
    }
    /// 尝试写入数据
    pub fn try_write(&mut self, item: T) -> bool {
        let write_pos: _ = self.write_index.load();
        let read_pos: _ = self.read_index.load();
        // 检查缓冲区是否已满
        if (write_pos + 1) % self.capacity == read_pos % self.capacity {
            return false;
        }
        let index: _ = write_pos % self.capacity;
        // 注意：在实际实现中，需要使用原子操作或锁来安全地修改buffer
        self.buffer[index] = Some(item);
        self.write_index.increment();
        true
    }
    /// 尝试读取数据
    pub fn try_read(&mut self) -> Option<T> {
        let write_pos: _ = self.write_index.load();
        let read_pos: _ = self.read_index.load();
        // 检查缓冲区是否为空
        if write_pos == read_pos {
            return None;
        }
        let index: _ = read_pos % self.capacity;
        let item: _ = self.buffer[index].take();
        if item.is_some() {
            self.read_index.increment();
        }
        item
    }
    /// 获取缓冲区使用率
    pub fn utilization(&self) -> f64 {
        let write_pos: _ = self.write_index.load();
        let read_pos: _ = self.read_index.load();
        let used: _ = (write_pos - read_pos).max(0) as f64;
        used / self.capacity as f64
    }
}
#[cfg(test)]
mod tests {
    #[test]
    fn test_zero_copy_buffer() {
        let data: _ = vec![1, 2, 3, 4, 5];
        let buffer: _ = ZeroCopyBuffer::new(data.clone());
        assert_eq!(buffer.len(), 5);
        assert_eq!(buffer.as_slice(), &data);
        // 测试克隆
        let cloned: _ = buffer.duplicate();
        assert_eq!(cloned.as_slice(), &data);
        assert!(Arc::ptr_eq(&buffer.data, &cloned.data));
    }
    #[test]
    fn test_zero_copy_channel() {
        let channel: _ = ZeroCopyChannel::new(10);
        // 发送数据
        channel.send(42).unwrap();
        // 接收数据
        let received: _ = channel.recv().unwrap();
        assert_eq!(received, 42);
    }
    #[tokio::test]
    async fn test_zero_copy_file_reader() {
        let temp_dir: _ = TempDir::new().unwrap();
        let file_path: _ = temp_dir.path().join("test.txt");
        fs::write(&file_path, "Hello, World!").unwrap();
        let mut reader = ZeroCopyFileReader::new(file_path.to_str().unwrap()).await.unwrap();
        let buffer: _ = reader.read_to_buffer().await.unwrap();
        assert_eq!(buffer.len(), 13);
        assert_eq!(buffer.as_slice(), b"Hello, World!");
    }
    #[tokio::test]
    async fn test_zero_copy_file_writer() {
        let temp_dir: _ = TempDir::new().unwrap();
        let file_path: _ = temp_dir.path().join("output.txt");
        let buffer: _ = ZeroCopyBuffer::from_slice(b"Test Data");
        let mut writer = ZeroCopyFileWriter::new(file_path.to_str().unwrap()).await.unwrap();
        let bytes_written: _ = writer.write_from_buffer(&buffer).await.unwrap();
        assert_eq!(bytes_written, 9);
        // 验证文件内容
        let content: _ = fs::read_to_string(file_path).unwrap();
        assert_eq!(content, "Test Data");
    }
    #[test]
    fn test_zero_copy_message() {
        let message: _ = ZeroCopyMessage::new_with_priority("test".to_string(), 5);
        assert_eq!(message.get_metadata().priority, 5);
        assert_eq!(message.get_data(), &"test".to_string());
    }
    #[test]
    fn test_zero_copy_ring_buffer() {
        let mut buffer = ZeroCopyRingBuffer::new(5);
        // 写入数据
        assert!(buffer.try_write(1));
        assert!(buffer.try_write(2));
        assert!(buffer.try_write(3));
        // 读取数据
        assert_eq!(buffer.try_read(), Some(1));
        assert_eq!(buffer.try_read(), Some(2));
        // 检查使用率
        assert!(buffer.utilization() > 0.0);
    }
    #[test]
    fn test_zero_copy_manager() {
        let manager: _ = ZeroCopyManager::new();
        // 创建缓冲区
        let buffer: _ = manager.create_buffer(vec![1, 2, 3]);
        assert_eq!(buffer.len(), 3);
        // 创建通道
        let channel: _ = manager.create_channel::<i32>(10);
        assert!(channel.send(42).is_ok());
        // 获取统计信息
        let stats: _ = manager.get_stats();
        assert!(stats.contains("Buffer Pool"));
        assert!(stats.contains("Channel Stats"));
    }
    #[test]
    fn test_atomic_operations_performance() {
        let counter: _ = Arc::new(Mutex::new(LockFreeCounter::new(0)));
        let iterations: _ = 100000;
        let thread_count: _ = 4;
        let start: _ = std::time::Instant::now();
        let handles: Vec<_> = (0..thread_count)
            .map(|_| {
                let counter: _ = counter.clone();
                std::thread::spawn(move || {
                    for _ in 0..iterations {
                        counter.increment();
                    }
                })
            })
            .collect();
        for handle in handles {
            handle.join().unwrap();
        }
        let elapsed: _ = start.elapsed();
        let total_ops: _ = counter.load();
        println!("{} 个线程执行 {} 次原子操作，总计 {} 次，耗时: {:?}",
                 thread_count, iterations, total_ops, elapsed);
        assert_eq!(total_ops, thread_count * iterations);
        assert!(elapsed.as_millis() < 1000); // 应该在1秒内完成
    }
}
/// 零拷贝文件缓存管理器
#[derive(Debug)]
#[allow(dead_code)]
pub struct ZeroCopyFileCache {
    /// 缓存的文件映射
    cache: Arc<Mutex<lru::LruCache<String, Arc<memmap2::Mmap>>>>,
    /// 最大缓存条目数
    max_entries: usize,
    /// 缓存统计
    stats: Arc<AtomicStats>,
}
#[allow(dead_code)]
impl ZeroCopyFileCache {
    /// 创建新的文件缓存管理器
    pub fn new(max_entries: usize) -> Self {
        Self {
            cache: Arc::new(Mutex::new(lru::LruCache::new(
                std::num::NonZeroUsize::new(max_entries)
            ).unwrap())),
            max_entries,
            stats: Arc::new(Mutex::new(AtomicStats::new())),
        }
    }
    /// 获取或加载文件到缓存
    pub async fn get_or_load(&self, path: &str) -> Result<Arc<memmap2::Mmap>, std::io::Error> {
        let path_string: _ = path.to_string();
        // 首先检查缓存
        {
            let mut cache = self.cache.lock().unwrap();
            if let Some(mapping) = cache.get(&path_string) {
                self.stats.record_operation("cache_hit");
                return Ok(Arc::clone(mapping));
            }
        }
        // 缓存未命中，加载文件
        let file: _ = tokio::fs::File::open(path).await?;
        let mapping: _ = unsafe { memmap2::MmapOptions::new().map(&file)? };
        let mapping: _ = Arc::new(Mutex::new(mapping));
        // 添加到缓存
        {
            let mut cache = self.cache.lock().unwrap();
            cache.put(path_string, Arc::clone(mapping));
        }
        self.stats.record_operation("cache_miss");
        Ok(mapping)
    }
    /// 预加载文件到缓存
    pub async fn preload(&self, path: &str) -> Result<(), std::io::Error> {
        let _: _ = self.get_or_load(path).await?;
        Ok(())
    }
    /// 从缓存中移除文件
    pub fn remove(&self, path: &str) -> Option<Arc<memmap2::Mmap>> {
        let mut cache = self.cache.lock().unwrap();
        cache.pop(path)
    }
    /// 清空缓存
    pub fn clear(&self) {
        let mut cache = self.cache.lock().unwrap();
        cache.clear();
    }
    /// 获取缓存统计
    pub fn get_stats(&self) -> String {
        let cache: _ = self.cache.lock().unwrap();
        format!(
            "Zero-copy file cache: {} entries (max: {}), operations: {}",
            cache.len(),
            self.max_entries,
            self.stats.get_report()
        )
    }
}
/// 零拷贝 I/O 性能监控器
#[derive(Debug)]
#[allow(dead_code)]
pub struct ZeroCopyIoMonitor {
    /// 总零拷贝字节数
    zero_copy_bytes: Arc<AtomicUsize>,
    /// 总复制字节数
    copied_bytes: Arc<AtomicUsize>,
    /// 文件操作计数
    file_ops: Arc<AtomicUsize>,
    /// 缓存命中率
    cache_hits: Arc<AtomicUsize>,
    /// 缓存未命中数
    cache_misses: Arc<AtomicUsize>,
}
#[allow(dead_code)]
impl ZeroCopyIoMonitor {
    /// 创建新的 I/O 监控器
    pub fn new() -> Self {
        Self {
            zero_copy_bytes: Arc::new(Mutex::new(AtomicUsize::new(0))),
            copied_bytes: Arc::new(Mutex::new(AtomicUsize::new(0))),
            file_ops: Arc::new(Mutex::new(AtomicUsize::new(0))),
            cache_hits: Arc::new(Mutex::new(AtomicUsize::new(0))),
            cache_misses: Arc::new(Mutex::new(AtomicUsize::new(0))),
        }
    }
    /// 记录零拷贝操作
    pub fn record_zero_copy(&self, bytes: usize) {
        self.zero_copy_bytes.fetch_add(bytes, Ordering::Relaxed);
        self.file_ops.fetch_add(1, Ordering::Relaxed);
    }
    /// 记录复制操作
    pub fn record_copy(&self, bytes: usize) {
        self.copied_bytes.fetch_add(bytes, Ordering::Relaxed);
        self.file_ops.fetch_add(1, Ordering::Relaxed);
    }
    /// 记录缓存命中
    pub fn record_cache_hit(&self) {
        self.cache_hits.fetch_add(1, Ordering::Relaxed);
    }
    /// 记录缓存未命中
    pub fn record_cache_miss(&self) {
        self.cache_misses.fetch_add(1, Ordering::Relaxed);
    }
    /// 获取零拷贝比率
    pub fn get_zero_copy_ratio(&self) -> f64 {
        let zero_copy: _ = self.zero_copy_bytes.load(Ordering::Relaxed) as f64;
        let total: _ = zero_copy + self.copied_bytes.load(Ordering::Relaxed) as f64;
        if total > 0.0 { zero_copy / total } else { 0.0 }
    }
    /// 获取缓存命中率
    pub fn get_cache_hit_rate(&self) -> f64 {
        let hits: _ = self.cache_hits.load(Ordering::Relaxed) as f64;
        let total: _ = hits + self.cache_misses.load(Ordering::Relaxed) as f64;
        if total > 0.0 { hits / total } else { 0.0 }
    }
    /// 获取性能报告
    pub fn get_performance_report(&self) -> String {
        let zero_copy: _ = self.zero_copy_bytes.load(Ordering::Relaxed);
        let copied: _ = self.copied_bytes.load(Ordering::Relaxed);
        let file_ops: _ = self.file_ops.load(Ordering::Relaxed);
        let cache_hit_rate: _ = self.get_cache_hit_rate();
        let zero_copy_ratio: _ = self.get_zero_copy_ratio();
        format!(
            "Zero-copy I/O Performance Report:\n\
             - Total file operations: {}\n\
             - Zero-copy bytes: {} ({:.2}%)\n\
             - Copied bytes: {} ({:.2}%)\n\
             - Cache hit rate: {:.2}%\n\
             - Zero-copy ratio: {:.2}%",
            file_ops,
            zero_copy,
            zero_copy_ratio * 100.0,
            copied,
            (1.0 - zero_copy_ratio) * 100.0,
            cache_hit_rate * 100.0,
            zero_copy_ratio * 100.0
        )
    }
}