func TestDirectIo(t *testing.T) {
// Make a temporary file name
fd, err := ioutil.TempFile("", "direct_io_test")
if err != nil {
t.Fatal("Failed to make temp file", err)
}
path := fd.Name()
fd.Close()
// starting block
block1 := directio.AlignedBlock(directio.BlockSize)
for i := 0; i < len(block1); i++ {
block1[i] = 'A'
}
// Write the file
out, err := directio.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0666)
if err != nil {
t.Fatal("Failed to directio.OpenFile for read", err)
}
_, err = out.Write(block1)
if err != nil {
t.Fatal("Failed to write", err)
}
err = out.Close()
if err != nil {
t.Fatal("Failed to close writer", err)
}
// Read the file
block2 := directio.AlignedBlock(directio.BlockSize)
in, err := directio.OpenFile(path, os.O_RDONLY, 0666)
if err != nil {
t.Fatal("Failed to directio.OpenFile for write", err)
}
_, err = io.ReadFull(in, block2)
if err != nil {
t.Fatal("Failed to read", err)
}
err = in.Close()
if err != nil {
t.Fatal("Failed to close reader", err)
}
// Tidy
err = os.Remove(path)
if err != nil {
t.Fatal("Failed to remove temp file", path, err)
}
// Compare
if !bytes.Equal(block1, block2) {
t.Fatal("Read not the same as written")
}
}
// WriteFile writes the random source for size bytes to the file given
//
// Returns a true if the write failed, false otherwise.
func WriteFile(file string, size int64) bool {
out, err := directio.OpenFile(file, os.O_CREATE|os.O_WRONLY, 0666)
if err != nil {
log.Fatalf("Couldn't open file %q for write: %s\n", file, err)
}
log.Printf("Writing file %q size %d\n", file, size)
failed := false
random := NewRandom()
br := NewBlockReader(random, "random")
defer br.Close()
for size > 0 {
block := br.Read()
_, err := out.Write(block)
br.Return(block)
if err != nil {
log.Printf("Error while writing %q\n", file)
failed = true
break
}
size -= BlockSize
stats.Written(BlockSize)
}
out.Close()
if failed {
log.Printf("Removing incomplete file %q\n", file)
err = os.Remove(file)
if err != nil {
log.Fatalf("Failed to remove incomplete file %q: %s\n", file, err)
}
}
return failed
}
// ReadFile reads the file given and checks it against the random source
func ReadFile(file string) {
in, err := directio.OpenFile(file, os.O_RDONLY, 0666)
if err != nil {
log.Fatalf("Failed to open %s for reading: %s\n", file, err)
}
defer in.Close()
random := NewRandom()
pos := int64(0)
log.Printf("Reading file %q\n", file)
// FIXME this is similar code to ReadTwoFiles
br1 := NewBlockReader(in, file)
defer br1.Close()
br2 := NewBlockReader(random, "random")
defer br2.Close()
output := true
for {
block1 := br1.Read()
block2 := br2.Read()
if block1 == nil {
break
}
if bytes.Compare(block1, block2) != 0 {
output = outputDiff(pos, block1, block2, output)
}
pos += BlockSize
br1.Return(block1)
br2.Return(block2)
}
}
func (s *streamSender) Run() error {
if err := s.prepare(); err != nil {
return err
}
if err := s.putHeader(&s.header); err != nil {
return err
}
if len(s.srcname) > 0 {
// always activate original lv so that target lv can be activated later
if err := lvmutil.ActivateLv(s.vgname, s.srcname); err != nil {
return err
}
defer lvmutil.DeactivateLv(s.vgname, s.srcname)
}
if err := lvmutil.ActivateLv(s.vgname, s.lvname); err != nil {
return err
}
defer lvmutil.DeactivateLv(s.vgname, s.lvname)
devpath := lvmutil.LvDevicePath(s.vgname, s.lvname)
devFile, err := directio.OpenFile(devpath, os.O_RDONLY, 0644)
if err != nil {
return err
}
defer devFile.Close()
buf := directio.AlignedBlock(int(s.header.BlockSize))
blockSize := int64(s.header.BlockSize)
for _, e := range s.blocks {
if e.OpType == thindump.DeltaOpDelete {
for i := 0; i < len(buf); i++ {
buf[i] = 0
}
} else {
if _, err := devFile.Seek(e.OriginBlock*blockSize, os.SEEK_SET); err != nil {
return err
}
if _, err := io.ReadFull(devFile, buf); err != nil {
return err
}
}
if err := s.putBlock(e.OriginBlock, buf); err != nil {
return err
}
}
return nil
}
// ReadTwoFiles reads two files and checks them to be the same as it goes along.
//
// It reads the files in BlockSize chunks.
func ReadTwoFiles(file1, file2 string) {
in1, err := directio.OpenFile(file1, os.O_RDONLY, 0666)
if err != nil {
log.Fatalf("Couldn't open file %q for read\n", file1)
}
defer in1.Close()
in2, err := directio.OpenFile(file2, os.O_RDONLY, 0666)
if err != nil {
log.Fatalf("Couldn't open file %q for read\n", file2)
}
defer in2.Close()
log.Printf("Reading file %q, %q\n", file1, file2)
stats.SetMode(modeRead)
defer stats.SetMode(modeReadDone)
pos := int64(0)
br1 := NewBlockReader(in1, file1)
defer br1.Close()
br2 := NewBlockReader(in2, file2)
defer br2.Close()
output := true
for {
block1 := br1.Read()
block2 := br2.Read()
if block1 == nil || block2 == nil {
if block1 != nil || block2 != nil {
log.Fatalf("Files %q and %q are different sizes\n", file1, file2)
}
break
}
if bytes.Compare(block1, block2) != 0 {
output = outputDiff(pos, block1, block2, output)
}
pos += BlockSize
br1.Return(block1)
br2.Return(block2)
}
}
func main() {
// Get hold of the current working dir
cwd, err := os.Getwd()
fatalIfErr(err)
// Create a temporary file
fd, err := ioutil.TempFile(cwd, "sleepless")
fatalIfErr(err)
// We just need the file name, we're going to reopen it with the right flags
path := fd.Name()
fd.Close()
// Allocate a block which will be filled with garbage on each iteration
garbage := directio.AlignedBlock(directio.BlockSize)
// Get ready
out, err := directio.OpenFile(path, os.O_CREATE|os.O_RDWR|os.O_SYNC, 0600)
fatalIfErr(err)
// Setup signal handling
sigint := make(chan os.Signal, 1)
signal.Notify(sigint, os.Interrupt)
go func() {
<-sigint
cleanup(out, path)
os.Exit(0)
}()
// Start the main loop
for {
// Garbage in...
if _, err = rand.Read(garbage); err != nil {
cleanup(out, path)
log.Fatal(err)
}
// ... garbage out
if _, err = out.Write(garbage); err != nil {
cleanup(out, path)
log.Fatal(err)
}
// Rewind the file to the start so that it does not grow
// indefintely
if _, err = out.Seek(0, os.SEEK_SET); err != nil {
cleanup(out, path)
log.Fatal(err)
}
// Take a nap
time.Sleep(10 * time.Second)
}
}
func Open(path string, sch Scheduler) (Disk, error) {
stat, err := os.Stat(path)
if err != nil {
return nil, err
}
f, err := directio.OpenFile(path, os.O_RDWR, 0666)
if err != nil {
return nil, err
}
return &disk{
f: f,
sch: sch,
size: uint64(stat.Size()),
path: path,
}, nil
}
func (sr *streamRecver) recvNextStream() error {
if err := sr.prepare(); err != nil {
return err
}
devpath := lvmutil.LvDevicePath(sr.vgname, sr.lvname)
devFile, err := directio.OpenFile(devpath, os.O_WRONLY, 0644)
if err != nil {
return err
}
defer devFile.Close()
n := 8 + sr.header.BlockSize
b := make([]byte, n+md5.Size)
buf := directio.AlignedBlock(int(sr.header.BlockSize))
for i := uint64(0); i < sr.header.BlockCount; i++ {
if _, err := io.ReadFull(sr.r, b); err != nil {
return err
}
sr.h.Reset()
sr.h.Write(b[:n])
if !bytes.Equal(sr.h.Sum(nil), b[n:n+md5.Size]) {
return fmt.Errorf("check sum mismatch for %dst block", i)
}
index := int64(binary.BigEndian.Uint64(b))
copy(buf, b[8:n])
if _, err := devFile.Seek(int64(sr.header.BlockSize)*index, os.SEEK_SET); err != nil {
return err
}
if _, err := devFile.Write(buf); err != nil {
return err
}
}
sr.prevUUID = string(sr.header.VolumeUUID[:])
return nil
}
func (c *OSClient) open(filename string, flags int) (File, error) {
fullpath := path.Join(c.RootDir, filename)
var f *os.File
var err error
if c.Direct {
f, err = directio.OpenFile(fullpath, flags, 0666)
} else {
f, err = os.OpenFile(fullpath, flags, 0644)
}
if err != nil {
return nil, err
}
return &OSFile{
BaseFile: BaseFile{filename: fullpath},
file: f,
}, nil
}