mirror of
				https://github.com/superseriousbusiness/gotosocial.git
				synced 2025-11-03 20:12:25 -06:00 
			
		
		
		
	
		
			
				
	
	
		
			141 lines
		
	
	
	
		
			3.4 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			141 lines
		
	
	
	
		
			3.4 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Copyright 2019+ Klaus Post. All rights reserved.
 | 
						|
// License information can be found in the LICENSE file.
 | 
						|
 | 
						|
package zstd
 | 
						|
 | 
						|
import (
 | 
						|
	"errors"
 | 
						|
	"io"
 | 
						|
	"sync"
 | 
						|
)
 | 
						|
 | 
						|
// ZipMethodWinZip is the method for Zstandard compressed data inside Zip files for WinZip.
 | 
						|
// See https://www.winzip.com/win/en/comp_info.html
 | 
						|
const ZipMethodWinZip = 93
 | 
						|
 | 
						|
// ZipMethodPKWare is the original method number used by PKWARE to indicate Zstandard compression.
 | 
						|
// Deprecated: This has been deprecated by PKWARE, use ZipMethodWinZip instead for compression.
 | 
						|
// See https://pkware.cachefly.net/webdocs/APPNOTE/APPNOTE-6.3.9.TXT
 | 
						|
const ZipMethodPKWare = 20
 | 
						|
 | 
						|
// zipReaderPool is the default reader pool.
 | 
						|
var zipReaderPool = sync.Pool{New: func() interface{} {
 | 
						|
	z, err := NewReader(nil, WithDecoderLowmem(true), WithDecoderMaxWindow(128<<20), WithDecoderConcurrency(1))
 | 
						|
	if err != nil {
 | 
						|
		panic(err)
 | 
						|
	}
 | 
						|
	return z
 | 
						|
}}
 | 
						|
 | 
						|
// newZipReader creates a pooled zip decompressor.
 | 
						|
func newZipReader(opts ...DOption) func(r io.Reader) io.ReadCloser {
 | 
						|
	pool := &zipReaderPool
 | 
						|
	if len(opts) > 0 {
 | 
						|
		opts = append([]DOption{WithDecoderLowmem(true), WithDecoderMaxWindow(128 << 20)}, opts...)
 | 
						|
		// Force concurrency 1
 | 
						|
		opts = append(opts, WithDecoderConcurrency(1))
 | 
						|
		// Create our own pool
 | 
						|
		pool = &sync.Pool{}
 | 
						|
	}
 | 
						|
	return func(r io.Reader) io.ReadCloser {
 | 
						|
		dec, ok := pool.Get().(*Decoder)
 | 
						|
		if ok {
 | 
						|
			dec.Reset(r)
 | 
						|
		} else {
 | 
						|
			d, err := NewReader(r, opts...)
 | 
						|
			if err != nil {
 | 
						|
				panic(err)
 | 
						|
			}
 | 
						|
			dec = d
 | 
						|
		}
 | 
						|
		return &pooledZipReader{dec: dec, pool: pool}
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
type pooledZipReader struct {
 | 
						|
	mu   sync.Mutex // guards Close and Read
 | 
						|
	pool *sync.Pool
 | 
						|
	dec  *Decoder
 | 
						|
}
 | 
						|
 | 
						|
func (r *pooledZipReader) Read(p []byte) (n int, err error) {
 | 
						|
	r.mu.Lock()
 | 
						|
	defer r.mu.Unlock()
 | 
						|
	if r.dec == nil {
 | 
						|
		return 0, errors.New("read after close or EOF")
 | 
						|
	}
 | 
						|
	dec, err := r.dec.Read(p)
 | 
						|
	if err == io.EOF {
 | 
						|
		r.dec.Reset(nil)
 | 
						|
		r.pool.Put(r.dec)
 | 
						|
		r.dec = nil
 | 
						|
	}
 | 
						|
	return dec, err
 | 
						|
}
 | 
						|
 | 
						|
func (r *pooledZipReader) Close() error {
 | 
						|
	r.mu.Lock()
 | 
						|
	defer r.mu.Unlock()
 | 
						|
	var err error
 | 
						|
	if r.dec != nil {
 | 
						|
		err = r.dec.Reset(nil)
 | 
						|
		r.pool.Put(r.dec)
 | 
						|
		r.dec = nil
 | 
						|
	}
 | 
						|
	return err
 | 
						|
}
 | 
						|
 | 
						|
type pooledZipWriter struct {
 | 
						|
	mu   sync.Mutex // guards Close and Read
 | 
						|
	enc  *Encoder
 | 
						|
	pool *sync.Pool
 | 
						|
}
 | 
						|
 | 
						|
func (w *pooledZipWriter) Write(p []byte) (n int, err error) {
 | 
						|
	w.mu.Lock()
 | 
						|
	defer w.mu.Unlock()
 | 
						|
	if w.enc == nil {
 | 
						|
		return 0, errors.New("Write after Close")
 | 
						|
	}
 | 
						|
	return w.enc.Write(p)
 | 
						|
}
 | 
						|
 | 
						|
func (w *pooledZipWriter) Close() error {
 | 
						|
	w.mu.Lock()
 | 
						|
	defer w.mu.Unlock()
 | 
						|
	var err error
 | 
						|
	if w.enc != nil {
 | 
						|
		err = w.enc.Close()
 | 
						|
		w.pool.Put(w.enc)
 | 
						|
		w.enc = nil
 | 
						|
	}
 | 
						|
	return err
 | 
						|
}
 | 
						|
 | 
						|
// ZipCompressor returns a compressor that can be registered with zip libraries.
 | 
						|
// The provided encoder options will be used on all encodes.
 | 
						|
func ZipCompressor(opts ...EOption) func(w io.Writer) (io.WriteCloser, error) {
 | 
						|
	var pool sync.Pool
 | 
						|
	return func(w io.Writer) (io.WriteCloser, error) {
 | 
						|
		enc, ok := pool.Get().(*Encoder)
 | 
						|
		if ok {
 | 
						|
			enc.Reset(w)
 | 
						|
		} else {
 | 
						|
			var err error
 | 
						|
			enc, err = NewWriter(w, opts...)
 | 
						|
			if err != nil {
 | 
						|
				return nil, err
 | 
						|
			}
 | 
						|
		}
 | 
						|
		return &pooledZipWriter{enc: enc, pool: &pool}, nil
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// ZipDecompressor returns a decompressor that can be registered with zip libraries.
 | 
						|
// See ZipCompressor for example.
 | 
						|
// Options can be specified. WithDecoderConcurrency(1) is forced,
 | 
						|
// and by default a 128MB maximum decompression window is specified.
 | 
						|
// The window size can be overridden if required.
 | 
						|
func ZipDecompressor(opts ...DOption) func(r io.Reader) io.ReadCloser {
 | 
						|
	return newZipReader(opts...)
 | 
						|
}
 |