bourdon
ae87c38776
- Core engine with MemTable, SST, WAL - B+Tree indexing for SST files - Leveled compaction strategy - Multi-table database management - Schema validation and secondary indexes - Query builder with complex conditions - Web UI with HTMX for data visualization - Command-line tools for diagnostics
49 lines
800 B
Go
49 lines
800 B
Go
package manifest
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import (
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"encoding/binary"
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"io"
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)
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// Reader MANIFEST 读取器
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type Reader struct {
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file io.Reader
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}
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// NewReader 创建 MANIFEST 读取器
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func NewReader(file io.Reader) *Reader {
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return &Reader{
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file: file,
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}
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}
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// ReadEdit 读取版本变更
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func (r *Reader) ReadEdit() (*VersionEdit, error) {
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// 读取 CRC32 和 Length
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header := make([]byte, 8)
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_, err := io.ReadFull(r.file, header)
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if err != nil {
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return nil, err
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}
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// 读取长度
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length := binary.LittleEndian.Uint32(header[4:8])
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// 读取数据
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data := make([]byte, 8+length)
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copy(data[0:8], header)
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_, err = io.ReadFull(r.file, data[8:])
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if err != nil {
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return nil, err
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}
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// 解码
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edit := NewVersionEdit()
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err = edit.Decode(data)
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if err != nil {
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return nil, err
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}
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return edit, nil
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}
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