gitea/models/dbfs/dbfile.go
Jason Song 6daf21c9b7
Fix content holes in Actions task logs file (#25560)
Fix #25451.

Bugfixes:
- When stopping the zombie or endless tasks, set `LogInStorage` to true
after transferring the file to storage. It was missing, it could write
to a nonexistent file in DBFS because `LogInStorage` was false.
- Always update `ActionTask.Updated` when there's a new state reported
by the runner, even if there's no change. This is to avoid the task
being judged as a zombie task.

Enhancement:
- Support `Stat()` for DBFS file.
- `WriteLogs` refuses to write if it could result in content holes.

---------

Co-authored-by: Giteabot <teabot@gitea.io>
2023-06-28 19:07:29 +02:00

376 lines
8.0 KiB
Go

// Copyright 2022 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package dbfs
import (
"context"
"errors"
"io"
"io/fs"
"os"
"path/filepath"
"strconv"
"strings"
"time"
"code.gitea.io/gitea/models/db"
)
var defaultFileBlockSize int64 = 32 * 1024
type File interface {
io.ReadWriteCloser
io.Seeker
fs.File
}
type file struct {
ctx context.Context
metaID int64
fullPath string
blockSize int64
allowRead bool
allowWrite bool
offset int64
}
var _ File = (*file)(nil)
func (f *file) readAt(fileMeta *dbfsMeta, offset int64, p []byte) (n int, err error) {
if offset >= fileMeta.FileSize {
return 0, io.EOF
}
blobPos := int(offset % f.blockSize)
blobOffset := offset - int64(blobPos)
blobRemaining := int(f.blockSize) - blobPos
needRead := len(p)
if needRead > blobRemaining {
needRead = blobRemaining
}
if blobOffset+int64(blobPos)+int64(needRead) > fileMeta.FileSize {
needRead = int(fileMeta.FileSize - blobOffset - int64(blobPos))
}
if needRead <= 0 {
return 0, io.EOF
}
var fileData dbfsData
ok, err := db.GetEngine(f.ctx).Where("meta_id = ? AND blob_offset = ?", f.metaID, blobOffset).Get(&fileData)
if err != nil {
return 0, err
}
blobData := fileData.BlobData
if !ok {
blobData = nil
}
canCopy := len(blobData) - blobPos
if canCopy <= 0 {
canCopy = 0
}
realRead := needRead
if realRead > canCopy {
realRead = canCopy
}
if realRead > 0 {
copy(p[:realRead], fileData.BlobData[blobPos:blobPos+realRead])
}
for i := realRead; i < needRead; i++ {
p[i] = 0
}
return needRead, nil
}
func (f *file) Read(p []byte) (n int, err error) {
if f.metaID == 0 || !f.allowRead {
return 0, os.ErrInvalid
}
fileMeta, err := findFileMetaByID(f.ctx, f.metaID)
if err != nil {
return 0, err
}
n, err = f.readAt(fileMeta, f.offset, p)
f.offset += int64(n)
return n, err
}
func (f *file) Write(p []byte) (n int, err error) {
if f.metaID == 0 || !f.allowWrite {
return 0, os.ErrInvalid
}
fileMeta, err := findFileMetaByID(f.ctx, f.metaID)
if err != nil {
return 0, err
}
needUpdateSize := false
written := 0
for len(p) > 0 {
blobPos := int(f.offset % f.blockSize)
blobOffset := f.offset - int64(blobPos)
blobRemaining := int(f.blockSize) - blobPos
needWrite := len(p)
if needWrite > blobRemaining {
needWrite = blobRemaining
}
buf := make([]byte, f.blockSize)
readBytes, err := f.readAt(fileMeta, blobOffset, buf)
if err != nil && !errors.Is(err, io.EOF) {
return written, err
}
copy(buf[blobPos:blobPos+needWrite], p[:needWrite])
if blobPos+needWrite > readBytes {
buf = buf[:blobPos+needWrite]
} else {
buf = buf[:readBytes]
}
fileData := dbfsData{
MetaID: fileMeta.ID,
BlobOffset: blobOffset,
BlobData: buf,
}
if res, err := db.GetEngine(f.ctx).Exec("UPDATE dbfs_data SET revision=revision+1, blob_data=? WHERE meta_id=? AND blob_offset=?", buf, fileMeta.ID, blobOffset); err != nil {
return written, err
} else if updated, err := res.RowsAffected(); err != nil {
return written, err
} else if updated == 0 {
if _, err = db.GetEngine(f.ctx).Insert(&fileData); err != nil {
return written, err
}
}
written += needWrite
f.offset += int64(needWrite)
if f.offset > fileMeta.FileSize {
fileMeta.FileSize = f.offset
needUpdateSize = true
}
p = p[needWrite:]
}
fileMetaUpdate := dbfsMeta{
ModifyTimestamp: timeToFileTimestamp(time.Now()),
}
if needUpdateSize {
fileMetaUpdate.FileSize = f.offset
}
if _, err := db.GetEngine(f.ctx).ID(fileMeta.ID).Update(fileMetaUpdate); err != nil {
return written, err
}
return written, nil
}
func (f *file) Seek(n int64, whence int) (int64, error) {
if f.metaID == 0 {
return 0, os.ErrInvalid
}
newOffset := f.offset
switch whence {
case io.SeekStart:
newOffset = n
case io.SeekCurrent:
newOffset += n
case io.SeekEnd:
size, err := f.size()
if err != nil {
return f.offset, err
}
newOffset = size + n
default:
return f.offset, os.ErrInvalid
}
if newOffset < 0 {
return f.offset, os.ErrInvalid
}
f.offset = newOffset
return newOffset, nil
}
func (f *file) Close() error {
return nil
}
func (f *file) Stat() (os.FileInfo, error) {
if f.metaID == 0 {
return nil, os.ErrInvalid
}
fileMeta, err := findFileMetaByID(f.ctx, f.metaID)
if err != nil {
return nil, err
}
return fileMeta, nil
}
func timeToFileTimestamp(t time.Time) int64 {
return t.UnixMicro()
}
func fileTimestampToTime(timestamp int64) time.Time {
return time.UnixMicro(timestamp)
}
func (f *file) loadMetaByPath() (*dbfsMeta, error) {
var fileMeta dbfsMeta
if ok, err := db.GetEngine(f.ctx).Where("full_path = ?", f.fullPath).Get(&fileMeta); err != nil {
return nil, err
} else if ok {
f.metaID = fileMeta.ID
f.blockSize = fileMeta.BlockSize
return &fileMeta, nil
}
return nil, nil
}
func (f *file) open(flag int) (err error) {
// see os.OpenFile for flag values
if flag&os.O_WRONLY != 0 {
f.allowWrite = true
} else if flag&os.O_RDWR != 0 {
f.allowRead = true
f.allowWrite = true
} else /* O_RDONLY */ {
f.allowRead = true
}
if f.allowWrite {
if flag&os.O_CREATE != 0 {
if flag&os.O_EXCL != 0 {
// file must not exist.
if f.metaID != 0 {
return os.ErrExist
}
} else {
// create a new file if none exists.
if f.metaID == 0 {
if err = f.createEmpty(); err != nil {
return err
}
}
}
}
if flag&os.O_TRUNC != 0 {
if err = f.truncate(); err != nil {
return err
}
}
if flag&os.O_APPEND != 0 {
if _, err = f.Seek(0, io.SeekEnd); err != nil {
return err
}
}
return nil
}
// read only mode
if f.metaID == 0 {
return os.ErrNotExist
}
return nil
}
func (f *file) createEmpty() error {
if f.metaID != 0 {
return os.ErrExist
}
now := time.Now()
_, err := db.GetEngine(f.ctx).Insert(&dbfsMeta{
FullPath: f.fullPath,
BlockSize: f.blockSize,
CreateTimestamp: timeToFileTimestamp(now),
ModifyTimestamp: timeToFileTimestamp(now),
})
if err != nil {
return err
}
if _, err = f.loadMetaByPath(); err != nil {
return err
}
return nil
}
func (f *file) truncate() error {
if f.metaID == 0 {
return os.ErrNotExist
}
return db.WithTx(f.ctx, func(ctx context.Context) error {
if _, err := db.GetEngine(ctx).Exec("UPDATE dbfs_meta SET file_size = 0 WHERE id = ?", f.metaID); err != nil {
return err
}
if _, err := db.GetEngine(ctx).Delete(&dbfsData{MetaID: f.metaID}); err != nil {
return err
}
return nil
})
}
func (f *file) renameTo(newPath string) error {
if f.metaID == 0 {
return os.ErrNotExist
}
newPath = buildPath(newPath)
return db.WithTx(f.ctx, func(ctx context.Context) error {
if _, err := db.GetEngine(ctx).Exec("UPDATE dbfs_meta SET full_path = ? WHERE id = ?", newPath, f.metaID); err != nil {
return err
}
return nil
})
}
func (f *file) delete() error {
if f.metaID == 0 {
return os.ErrNotExist
}
return db.WithTx(f.ctx, func(ctx context.Context) error {
if _, err := db.GetEngine(ctx).Delete(&dbfsMeta{ID: f.metaID}); err != nil {
return err
}
if _, err := db.GetEngine(ctx).Delete(&dbfsData{MetaID: f.metaID}); err != nil {
return err
}
return nil
})
}
func (f *file) size() (int64, error) {
if f.metaID == 0 {
return 0, os.ErrNotExist
}
fileMeta, err := findFileMetaByID(f.ctx, f.metaID)
if err != nil {
return 0, err
}
return fileMeta.FileSize, nil
}
func findFileMetaByID(ctx context.Context, metaID int64) (*dbfsMeta, error) {
var fileMeta dbfsMeta
if ok, err := db.GetEngine(ctx).Where("id = ?", metaID).Get(&fileMeta); err != nil {
return nil, err
} else if ok {
return &fileMeta, nil
}
return nil, nil
}
func buildPath(path string) string {
path = filepath.Clean(path)
path = strings.ReplaceAll(path, "\\", "/")
path = strings.TrimPrefix(path, "/")
return strconv.Itoa(strings.Count(path, "/")) + ":" + path
}
func newDbFile(ctx context.Context, path string) (*file, error) {
path = buildPath(path)
f := &file{ctx: ctx, fullPath: path, blockSize: defaultFileBlockSize}
if _, err := f.loadMetaByPath(); err != nil {
return nil, err
}
return f, nil
}