// Copyright 2015 The Gogs Authors. All rights reserved.// Copyright 2019 The Gitea Authors. All rights reserved.// SPDX-License-Identifier: MIT package git import (	"bufio"	"bytes"	"encoding/base64"	"io" 	"forgejo.org/modules/log"	"forgejo.org/modules/typesniffer"	"forgejo.org/modules/util") // Blob represents a Git object.type Blob struct {	ID ObjectID 	gotSize bool	size    int64	name    string	repo    *Repository} // DataAsync gets a ReadCloser for the contents of a blob without reading it all.// Calling the Close function on the result will discard all unread output.func (b *Blob) DataAsync() (io.ReadCloser, error) {	wr, rd, cancel, err := b.repo.CatFileBatch(b.repo.Ctx)	if err != nil {		return nil, err	} 	_, err = wr.Write([]byte(b.ID.String() + "\n"))	if err != nil {		cancel()		return nil, err	}	_, _, size, err := ReadBatchLine(rd)	if err != nil {		cancel()		return nil, err	}	b.gotSize = true	b.size = size 	if size < 4096 {		bs, err := io.ReadAll(io.LimitReader(rd, size))		defer cancel()		if err != nil {			return nil, err		}		_, err = rd.Discard(1)		return io.NopCloser(bytes.NewReader(bs)), err	} 	return &blobReader{		rd:     rd,		n:      size,		cancel: cancel,	}, nil} // Size returns the uncompressed size of the blobfunc (b *Blob) Size() int64 {	if b.gotSize {		return b.size	} 	wr, rd, cancel, err := b.repo.CatFileBatchCheck(b.repo.Ctx)	if err != nil {		log.Debug("error whilst reading size for %s in %s. Error: %v", b.ID.String(), b.repo.Path, err)		return 0	}	defer cancel()	_, err = wr.Write([]byte(b.ID.String() + "\n"))	if err != nil {		log.Debug("error whilst reading size for %s in %s. Error: %v", b.ID.String(), b.repo.Path, err)		return 0	}	_, _, b.size, err = ReadBatchLine(rd)	if err != nil {		log.Debug("error whilst reading size for %s in %s. Error: %v", b.ID.String(), b.repo.Path, err)		return 0	} 	b.gotSize = true 	return b.size} type blobReader struct {	rd     *bufio.Reader	n      int64	cancel func()} func (b *blobReader) Read(p []byte) (n int, err error) {	if b.n <= 0 {		return 0, io.EOF	}	if int64(len(p)) > b.n {		p = p[0:b.n]	}	n, err = b.rd.Read(p)	b.n -= int64(n)	return n, err} // Close implements io.Closerfunc (b *blobReader) Close() error {	if b.rd == nil {		return nil	} 	defer b.cancel() 	if err := DiscardFull(b.rd, b.n+1); err != nil {		return err	} 	b.rd = nil 	return nil} // Name returns name of the tree entry this blob object was created from (or empty string)func (b *Blob) Name() string {	return b.name} // GetBlobContent Gets the limited content of the blob as raw textfunc (b *Blob) GetBlobContent(limit int64) (string, error) {	if limit <= 0 {		return "", nil	}	dataRc, err := b.DataAsync()	if err != nil {		return "", err	}	defer dataRc.Close()	buf, err := util.ReadWithLimit(dataRc, int(limit))	return string(buf), err} // GetBlobLineCount gets line count of the blobfunc (b *Blob) GetBlobLineCount() (int, error) {	reader, err := b.DataAsync()	if err != nil {		return 0, err	}	defer reader.Close()	buf := make([]byte, 32*1024)	count := 1	lineSep := []byte{'\n'} 	c, err := reader.Read(buf)	if c == 0 && err == io.EOF {		return 0, nil	}	for {		count += bytes.Count(buf[:c], lineSep)		switch {		case err == io.EOF:			return count, nil		case err != nil:			return count, err		}		c, err = reader.Read(buf)	}} // GetBlobContentBase64 Reads the content of the blob with a base64 encode and returns the encoded stringfunc (b *Blob) GetBlobContentBase64() (string, error) {	dataRc, err := b.DataAsync()	if err != nil {		return "", err	}	defer dataRc.Close() 	pr, pw := io.Pipe()	encoder := base64.NewEncoder(base64.StdEncoding, pw) 	go func() {		_, err := io.Copy(encoder, dataRc)		_ = encoder.Close() 		if err != nil {			_ = pw.CloseWithError(err)		} else {			_ = pw.Close()		}	}() 	out, err := io.ReadAll(pr)	if err != nil {		return "", err	}	return string(out), nil} // GuessContentType guesses the content type of the blob.func (b *Blob) GuessContentType() (typesniffer.SniffedType, error) {	r, err := b.DataAsync()	if err != nil {		return typesniffer.SniffedType{}, err	}	defer r.Close() 	return typesniffer.DetectContentTypeFromReader(r)} // GetBlob finds the blob object in the repository.func (repo *Repository) GetBlob(idStr string) (*Blob, error) {	id, err := NewIDFromString(idStr)	if err != nil {		return nil, err	}	if id.IsZero() {		return nil, ErrNotExist{id.String(), ""}	}	return &Blob{		ID:   id,		repo: repo,	}, nil}