Method read_files

nodedb/src/data/io/uring_reader.rs:100–244

Read multiple files in a single batched io_uring submission. Opens each file, submits `IORING_OP_READ` SQEs for all, then waits for all completions. Returns file contents in the same order as `paths`. Files that fail to open are returned as empty `Vec `.

(&mut self, paths: &[&Path])

    ///
    /// Files that fail to open are returned as empty `Vec<u8>`.
    pub fn read_files(&mut self, paths: &[&Path]) -> Vec<Vec<u8>> {
        if paths.is_empty() {
            return Vec::new();
        }

        // Phase 1: Open files, determine sizes, assign buffers.
        let mut reads: Vec<PendingRead> = Vec::with_capacity(paths.len());
        let mut oversized: Vec<AlignedBuf> = Vec::new();

        for (i, path) in paths.iter().enumerate() {
            let file = match std::fs::File::open(path) {
                Ok(f) => f,
                Err(_) => {
                    reads.push(PendingRead::failed(i));
                    continue;
                }
            };
            let size = file.metadata().map(|m| m.len() as usize).unwrap_or(0);
            if size == 0 {
                reads.push(PendingRead::failed(i));
                continue;
            }

            let buf_source = if size <= self.buf_size {
                if let Some(slot) = self.free.pop() {
                    BufSource::Pool(slot)
                } else {
                    // Pool exhausted — allocate dedicated.
                    match AlignedBuf::new(size) {
                        Ok(buf) => {
                            let idx = oversized.len();
                            oversized.push(buf);
                            BufSource::Oversized(idx)
                        }
                        Err(_) => {
                            reads.push(PendingRead::failed(i));
                            continue;
                        }
                    }
                }
            } else {
                match AlignedBuf::new(size) {
                    Ok(buf) => {
                        let idx = oversized.len();
                        oversized.push(buf);
                        BufSource::Oversized(idx)
                    }
                    Err(_) => {
                        reads.push(PendingRead::failed(i));
                        continue;
                    }
                }
            };

            reads.push(PendingRead {
                index: i,
                file: Some(file),
                size,