Golang Pwrite Examples

Example #1

File: main.go Project: krishnasrinivas/constor

func (constor *Constor) Write(input *fuse.WriteIn, data []byte) (written uint32, code fuse.Status) {
	constor.log("%d", input.Fh)
	ptr := uintptr(input.Fh)
	offset := input.Offset

	F := constor.getfd(ptr)
	if F == nil {
		constor.error("F == nil")
		return 0, fuse.EIO
	}
	inode, err := constor.inodemap.findInode(input.NodeId)
	if err != nil {
		constor.error("%s", err)
		return 0, fuse.ToStatus(err)
	}
	if F.layer != 0 && inode.layer != 0 {
		err = constor.copyup(inode)
		if err != nil {
			constor.error("%s", err)
			return 0, fuse.ToStatus(err)
		}
		path, err := constor.dentrymap.getPath(inode.ino)
		if err != nil {
			constor.error("%s", err)
			return 0, fuse.ToStatus(err)
		}
		pathl := Path.Join(constor.layers[0], path)
		syscall.Close(F.fd)
		fd, err := syscall.Open(pathl, F.flags, 0)
		if err != nil {
			constor.error("%s", err)
			return 0, fuse.ToStatus(err)
		}
		F.fd = fd
		F.layer = 0
		constor.log("reset fd for %s", path)
	} else if F.layer != 0 && inode.layer == 0 {
		syscall.Close(F.fd)
		path, err := constor.dentrymap.getPath(inode.ino)
		if err != nil {
			constor.error("%s", err)
			return 0, fuse.ToStatus(err)
		}
		pathl := Path.Join(constor.layers[0] + path)
		fd, err := syscall.Open(pathl, F.flags, 0)
		if err != nil {
			constor.error("%s", err)
			return 0, fuse.ToStatus(err)
		}
		F.fd = fd
		F.layer = 0
		constor.log("reset fd for %s", path)
	}

	fd := F.fd
	n, err := syscall.Pwrite(fd, data, int64(offset))
	return uint32(n), fuse.ToStatus(err)
}

Example #2

File: io.go Project: lunixbochs/usercorn

func (k *PosixKernel) Pwrite64(fd co.Fd, buf co.Buf, size co.Len, offset int64) uint64 {
	p := make([]byte, size)
	if err := buf.Unpack(p); err != nil {
		return UINT64_MAX // FIXME
	}
	n, err := syscall.Pwrite(int(fd), p, offset)
	if err != nil {
		return Errno(err)
	}
	return uint64(n)
}

Example #3

File: main.go Project: krishnasrinivas/confs

func (constor *Constor) Write(input *fuse.WriteIn, data []byte) (written uint32, code fuse.Status) {
	constor.log("%d %d", input.Fh, len(data))
	ptr := uintptr(input.Fh)
	offset := input.Offset
	wdata := data

	F := constor.getfd(ptr)
	if F == nil {
		constor.error("F == nil")
		return 0, fuse.EIO
	}
	if F.flags&syscall.O_DIRECT != 0 {
		wdata = directio.AlignedBlock(len(data))
		copy(wdata, data)
	}
	inode := constor.inodemap.findInodePtr(input.NodeId)
	if inode == nil {
		return 0, fuse.ENOENT
	}
	if F.layer != 0 && inode.layer != 0 {
		err := constor.copyup(inode)
		if err != nil {
			constor.error("%s", err)
			return 0, fuse.ToStatus(err)
		}
		path := constor.getPath(0, inode.id)
		syscall.Close(F.fd)
		fd, err := syscall.Open(path, F.flags, 0)
		if err != nil {
			constor.error("%s", err)
			return 0, fuse.ToStatus(err)
		}
		F.fd = fd
		F.layer = 0
		constor.log("reset fd for %s", path)
	} else if F.layer != 0 && inode.layer == 0 {
		syscall.Close(F.fd)
		path := constor.getPath(0, inode.id)
		fd, err := syscall.Open(path, F.flags, 0)
		if err != nil {
			constor.error("%s", err)
			return 0, fuse.ToStatus(err)
		}
		F.fd = fd
		F.layer = 0
		constor.log("reset fd for %s", path)
	}

	fd := F.fd
	n, err := syscall.Pwrite(fd, wdata, int64(offset))
	return uint32(n), fuse.ToStatus(err)
}

Example #4

File: beaglebone.go Project: enjenye/beaglebone

func (b Bone) WriteInt16(addr int, val uint16) error {
	data := make([]byte, 2)
	data[0] = byte((val) & 0x00FF)
	data[1] = byte((val >> 8) & 0x00FF)
	count, err := syscall.Pwrite(int(b), data, int64(addr))
	if err != nil {
		return err
	}
	if count != 2 {
		return errors.New("wrong number of bytes written")
	}
	return nil
}

Example #5

File: file.go Project: lougxing/golang-china

// WriteAt writes len(b) bytes to the File starting at byte offset off.
// It returns the number of bytes written and an Error, if any.
// WriteAt returns a non-nil Error when n != len(b).
func (file *File) WriteAt(b []byte, off int64) (n int, err Error) {
	if file == nil {
		return 0, EINVAL
	}
	for len(b) > 0 {
		m, e := syscall.Pwrite(file.fd, b, off)
		if e != 0 {
			err = &PathError{"write", file.name, Errno(e)}
			break
		}
		n += m
		b = b[m:]
		off += int64(m)
	}
	return
}

Example #6

File: file_plan9.go Project: kostyll/gccpy

// pwrite writes len(b) bytes to the File starting at byte offset off.
// It returns the number of bytes written and an error, if any.
// Since Plan 9 preserves message boundaries, never allow
// a zero-byte write.
func (f *File) pwrite(b []byte, off int64) (n int, err error) {
	if len(b) == 0 {
		return 0, nil
	}
	return syscall.Pwrite(f.fd, b, off)
}

Example #7

File: file_unix.go Project: kuangchanglang/go

// pwrite writes len(b) bytes to the File starting at byte offset off.
// It returns the number of bytes written and an error, if any.
func (f *File) pwrite(b []byte, off int64) (n int, err error) {
	if needsMaxRW && len(b) > maxRW {
		b = b[:maxRW]
	}
	return fixCount(syscall.Pwrite(f.fd, b, off))
}

Example #8

File: file_unix.go Project: gnanderson/go

// pwrite writes len(b) bytes to the File starting at byte offset off.
// It returns the number of bytes written and an error, if any.
func (f *File) pwrite(b []byte, off int64) (n int, err error) {
	return syscall.Pwrite(f.fd, b, off)
}

Example #9

File: syncio.go Project: lovefcaaa/split

func (s *SyncFile) Write(buf []byte, off int64) (n int, err error) {
	s.mutex.Lock()
	defer s.mutex.Unlock()
	return syscall.Pwrite(int(s.fp.Fd()), buf, off)
}