Python os.ftruncate() Examples

def init(self):
        self.control = socket.socket(socket.AF_UNIX)
        while True:
            try:
                self.control.connect(self.control_filename)
                #self.control.connect(self.control_filename)
                break
            except socket_error:
                pass
                #time.sleep(0.01)

        self.kafl_shm_f     = os.open(self.bitmap_filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
        self.fs_shm_f       = os.open(self.payload_filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
        #argv_fd             = os.open(self.argv_filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
        os.ftruncate(self.kafl_shm_f, self.bitmap_size)
        os.ftruncate(self.fs_shm_f, (128 << 10))
        #os.ftruncate(argv_fd, (4 << 10))

        self.kafl_shm       = mmap.mmap(self.kafl_shm_f, self.bitmap_size, mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
        self.fs_shm         = mmap.mmap(self.fs_shm_f, (128 << 10),  mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)

        return True 

def __set_binary(self, filename, binaryfile, max_size):
        shm_fd = os.open(filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
        os.ftruncate(shm_fd, max_size)
        shm = mmap.mmap(shm_fd, max_size, mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
        shm.seek(0x0)
        shm.write('\x00' * max_size)
        shm.seek(0x0)

        f = open(binaryfile, "rb")
        bytes = f.read(1024)
        if bytes:
            shm.write(bytes)
        while bytes != "":
            bytes = f.read(1024)
            if bytes:
                shm.write(bytes)

        f.close()
        shm.close()
        os.close(shm_fd) 

def init(self):
        self.control = safe_socket(socket.AF_UNIX)
        self.control.settimeout(None)
        self.control.setblocking(1)
        while True:
            try:
                self.control.connect(self.control_filename)
                break
            except socket_error:
                pass

        self.kafl_shm_f     = os.open(self.bitmap_filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
        self.fs_shm_f       = os.open(self.payload_filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
        os.ftruncate(self.kafl_shm_f, self.bitmap_size)
        os.ftruncate(self.fs_shm_f, (128 << 10))

        self.kafl_shm       = mmap.mmap(self.kafl_shm_f, self.bitmap_size, mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
        self.fs_shm         = mmap.mmap(self.fs_shm_f, (128 << 10),  mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)

        return True 

def __set_binary(self, filename, binaryfile, max_size):
        shm_fd = os.open(filename, os.O_RDWR | os.O_SYNC | os.O_CREAT)
        os.ftruncate(shm_fd, max_size)
        shm = mmap.mmap(shm_fd, max_size, mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
        shm.seek(0x0)
        shm.write('\x00' * max_size)
        shm.seek(0x0)

        f = open(binaryfile, "rb")
        bytes = f.read(1024)
        if bytes:
            shm.write(bytes)
        while bytes != "":
            bytes = f.read(1024)
            if bytes:
                shm.write(bytes)

        shm.flush()
        f.close()
        shm.close()
        os.close(shm_fd) 

def wipe(self):
    	filter_bitmap_fd = os.open("/dev/shm/kafl_filter0", os.O_RDWR | os.O_SYNC | os.O_CREAT)
        os.ftruncate(filter_bitmap_fd, self.config.config_values['BITMAP_SHM_SIZE'])
        filter_bitmap = mmap.mmap(filter_bitmap_fd, self.config.config_values['BITMAP_SHM_SIZE'], mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
        for i in range(self.config.config_values['BITMAP_SHM_SIZE']):
        	filter_bitmap[i] = '\x00'
        filter_bitmap.close()
        os.close(filter_bitmap_fd)

        filter_bitmap_fd = os.open("/dev/shm/kafl_tfilter", os.O_RDWR | os.O_SYNC | os.O_CREAT)
        os.ftruncate(filter_bitmap_fd, 0x1000000)
        filter_bitmap = mmap.mmap(filter_bitmap_fd, 0x1000000, mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
        for i in range(0x1000000):
        	filter_bitmap[i] = '\x00'
        filter_bitmap.close()
        os.close(filter_bitmap_fd) 

def wipe(self):
        filter_bitmap_fd = os.open("/dev/shm/kafl_filter0", os.O_RDWR | os.O_SYNC | os.O_CREAT)
        os.ftruncate(filter_bitmap_fd, self.config.config_values['BITMAP_SHM_SIZE'])
        filter_bitmap = mmap.mmap(filter_bitmap_fd, self.config.config_values['BITMAP_SHM_SIZE'], mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
        for i in range(self.config.config_values['BITMAP_SHM_SIZE']):
            filter_bitmap[i] = '\x00'
        filter_bitmap.close()
        os.close(filter_bitmap_fd)

        filter_bitmap_fd = os.open("/dev/shm/kafl_tfilter", os.O_RDWR | os.O_SYNC | os.O_CREAT)
        os.ftruncate(filter_bitmap_fd, 0x1000000)
        filter_bitmap = mmap.mmap(filter_bitmap_fd, 0x1000000, mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ)
        for i in range(0x1000000):
            filter_bitmap[i] = '\x00'
        filter_bitmap.close()
        os.close(filter_bitmap_fd) 

def create_shm(self):
        for j in range(len(self.files)):
            for i in range(self.num_processes):
                shm_f = os.open(self.files[j]+str(i), os.O_CREAT | os.O_RDWR | os.O_SYNC)
                os.ftruncate(shm_f, self.sizes[j]*self.tasks_per_requests)
                os.close(shm_f) 

def _general_print(head, color, msg = None, stream = None, level = 'normal'):
    global LOG_CONTENT
    if not stream:
        stream = sys.stdout

    if LOG_LEVELS[level] > LOG_LEVEL:
        # skip
        return

    errormsg = ''
    if CATCHERR_BUFFILE_FD > 0:
        size = os.lseek(CATCHERR_BUFFILE_FD , 0, os.SEEK_END)
        os.lseek(CATCHERR_BUFFILE_FD, 0, os.SEEK_SET)
        errormsg = os.read(CATCHERR_BUFFILE_FD, size)
        os.ftruncate(CATCHERR_BUFFILE_FD, 0)

    if LOG_FILE_FP:
        if errormsg:
            LOG_CONTENT += errormsg

        save_msg = msg.strip()
        if save_msg:
            timestr = datetime.now().strftime('[%m/%d %H:%M:%S] ')
            LOG_CONTENT += timestr + save_msg + '\n'

    if errormsg:
        _color_print('', NO_COLOR, errormsg, stream, level)

    _color_print(head, color, msg, stream, level) 

def test_ftruncate(self):
        self.fp.write('jython filenos')
        self.fp.flush()
        os.fsync(self.fd)
        self.assertEqual(os.path.getsize(self.filename), 14)
        os.ftruncate(self.fd, 8)
        self.assertEqual(os.path.getsize(self.filename), 8)
        os.ftruncate(self.fd, 0)
        self.assertEqual(os.path.getsize(self.filename), 0)

        self.fp.close()
        raises(OSError, 9, os.ftruncate, self.fd, 0) 

def test_ftruncate(self):
        if hasattr(os, "ftruncate"):
            self.check(os.ftruncate, 0) 

def truncate(self, size=None):
        """Truncate the file to at most size bytes.

        Size defaults to the current file position, as returned by tell().
        The current file position is changed to the value of size.
        """
        self._checkClosed()
        self._checkWritable()
        if size is None:
            size = self.tell()
        os.ftruncate(self._fd, size)
        return size 

def open_global_bitmap(self):
        self.global_bitmap_fd = os.open(self.config.argument_values['work_dir'] + "/bitmaps/bitmap", os.O_RDWR | os.O_SYNC | os.O_CREAT)
        os.ftruncate(self.global_bitmap_fd, self.bitmap_size)
        self.global_bitmap = mmap.mmap(self.global_bitmap_fd, self.bitmap_size, mmap.MAP_SHARED, mmap.PROT_WRITE | mmap.PROT_READ) 

def write_pid_file(pid_file, pid):
    import fcntl
    import stat

    try:
        fd = os.open(pid_file, os.O_RDWR | os.O_CREAT,
                     stat.S_IRUSR | stat.S_IWUSR)
    except OSError as e:
        shell.print_exception(e)
        return -1
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    assert flags != -1
    flags |= fcntl.FD_CLOEXEC
    r = fcntl.fcntl(fd, fcntl.F_SETFD, flags)
    assert r != -1
    # There is no platform independent way to implement fcntl(fd, F_SETLK, &fl)
    # via fcntl.fcntl. So use lockf instead
    try:
        fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB, 0, 0, os.SEEK_SET)
    except IOError:
        r = os.read(fd, 32)
        if r:
            logging.error('already started at pid %s' % common.to_str(r))
        else:
            logging.error('already started')
        os.close(fd)
        return -1
    os.ftruncate(fd, 0)
    os.write(fd, common.to_bytes(str(pid)))
    return 0 

def write_pid_file(pid_file, pid):
    import fcntl
    import stat

    try:
        fd = os.open(pid_file, os.O_RDWR | os.O_CREAT,
                     stat.S_IRUSR | stat.S_IWUSR)
    except OSError as e:
        shell.print_exception(e)
        return -1
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    assert flags != -1
    flags |= fcntl.FD_CLOEXEC
    r = fcntl.fcntl(fd, fcntl.F_SETFD, flags)
    assert r != -1
    # There is no platform independent way to implement fcntl(fd, F_SETLK, &fl)
    # via fcntl.fcntl. So use lockf instead
    try:
        fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB, 0, 0, os.SEEK_SET)
    except IOError:
        r = os.read(fd, 32)
        if r:
            logging.error('already started at pid %s' % common.to_str(r))
        else:
            logging.error('already started')
        os.close(fd)
        return -1
    os.ftruncate(fd, 0)
    os.write(fd, common.to_bytes(str(pid)))
    return 0 

def write_pid_file(pid_file, pid):
    import fcntl
    import stat

    try:
        fd = os.open(pid_file, os.O_RDWR | os.O_CREAT,
                     stat.S_IRUSR | stat.S_IWUSR)
    except OSError as e:
        shell.print_exception(e)
        return -1
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    assert flags != -1
    flags |= fcntl.FD_CLOEXEC
    r = fcntl.fcntl(fd, fcntl.F_SETFD, flags)
    assert r != -1
    # There is no platform independent way to implement fcntl(fd, F_SETLK, &fl)
    # via fcntl.fcntl. So use lockf instead
    try:
        fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB, 0, 0, os.SEEK_SET)
    except IOError:
        r = os.read(fd, 32)
        if r:
            logging.error('already started at pid %s' % common.to_str(r))
        else:
            logging.error('already started')
        os.close(fd)
        return -1
    os.ftruncate(fd, 0)
    os.write(fd, common.to_bytes(str(pid)))
    return 0 

def truncate(self, offset=0):
        return os.ftruncate(self.fd, offset) 

def delete_content(fd):
    os.ftruncate(fd, 0)
    os.lseek(fd, 0, os.SEEK_SET) 

def allocate_shm_file(filename, nbytes, dbytes, readonly):
  exists = os.path.exists(filename)
  size = 0 if not exists else os.path.getsize(filename)

  if readonly and not exists:
    raise SharedMemoryReadError(filename + " has not been allocated. Requested " + str(nbytes) + " bytes.")
  elif readonly and size != nbytes:
    raise SharedMemoryReadError("{} exists, but the allocation size ({} bytes) does not match the request ({} bytes).".format(
      filename, size, nbytes
    ))

  if exists: 
    if size > nbytes:
      with open(filename, 'wb') as f:
        os.ftruncate(f.fileno(), nbytes)
    elif size < nbytes:
      # too small? just remake it below
      os.unlink(filename) 

  exists = os.path.exists(filename)

  if not exists:
    # Previously we were writing out real files full of zeros, 
    # but a) that takes forever and b) modern OSes support sparse
    # files (i.e. gigabytes of zeros that take up only a few real bytes).
    #
    # The following should take advantage of this functionality and be faster.
    # It should work on Python 2.7 Unix, and Python 3.5+ on Unix and Windows.
    #
    # References:
    #   https://stackoverflow.com/questions/8816059/create-file-of-particular-size-in-python
    #   https://docs.python.org/3/library/os.html#os.ftruncate
    #   https://docs.python.org/2/library/os.html#os.ftruncate
    #
    with open(filename, 'wb') as f:
      os.ftruncate(f.fileno(), nbytes) 

def test_ftruncate(self):
        self.fp.write('jython filenos')
        self.fp.flush()
        os.fsync(self.fd)
        self.assertEqual(os.path.getsize(self.filename), 14)
        os.ftruncate(self.fd, 8)
        self.assertEqual(os.path.getsize(self.filename), 8)
        os.ftruncate(self.fd, 0)
        self.assertEqual(os.path.getsize(self.filename), 0)

        self.fp.close()
        raises(IOError, 9, os.ftruncate, self.fd, 0) 

def test_ftruncate(self):
        self.check(os.truncate, 0)
        self.check(os.ftruncate, 0) 

def truncate(self, size=None):
        """Truncate the file to at most size bytes.

        Size defaults to the current file position, as returned by tell().
        The current file position is changed to the value of size.
        """
        self._checkClosed()
        self._checkWritable()
        if size is None:
            size = self.tell()
        os.ftruncate(self._fd, size)
        return size 

def write_pid_file(pid_file, pid):
    import fcntl
    import stat

    try:
        fd = os.open(pid_file, os.O_RDWR | os.O_CREAT,
                     stat.S_IRUSR | stat.S_IWUSR)
    except OSError as e:
        shell.print_exception(e)
        return -1
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    assert flags != -1
    flags |= fcntl.FD_CLOEXEC
    r = fcntl.fcntl(fd, fcntl.F_SETFD, flags)
    assert r != -1
    # There is no platform independent way to implement fcntl(fd, F_SETLK, &fl)
    # via fcntl.fcntl. So use lockf instead
    try:
        fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB, 0, 0, os.SEEK_SET)
    except IOError:
        r = os.read(fd, 32)
        if r:
            logging.error('already started at pid %s' % common.to_str(r))
        else:
            logging.error('already started')
        os.close(fd)
        return -1
    os.ftruncate(fd, 0)
    os.write(fd, common.to_bytes(str(pid)))
    return 0 

def test_ftruncate(self):
        self.check(os.ftruncate, 0) 

def write_pid_file(pid_file, pid):
    import fcntl
    import stat

    try:
        fd = os.open(pid_file, os.O_RDWR | os.O_CREAT,
                     stat.S_IRUSR | stat.S_IWUSR)
    except OSError as e:
        shell.print_exception(e)
        return -1
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    assert flags != -1
    flags |= fcntl.FD_CLOEXEC
    r = fcntl.fcntl(fd, fcntl.F_SETFD, flags)
    assert r != -1
    # There is no platform independent way to implement fcntl(fd, F_SETLK, &fl)
    # via fcntl.fcntl. So use lockf instead
    try:
        fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB, 0, 0, os.SEEK_SET)
    except IOError:
        r = os.read(fd, 32)
        if r:
            logging.error('already started at pid %s' % common.to_str(r))
        else:
            logging.error('already started')
        os.close(fd)
        return -1
    os.ftruncate(fd, 0)
    os.write(fd, common.to_bytes(str(pid)))
    return 0 

def mmap(self, data):
        url = "mmap://{0}?offset=0&length={1}".format(
            self.temp.name, len(data))
        os.ftruncate(self.temp.fileno(), 4096)
        mm = mmap(self.temp.fileno(), 4096)
        mm.write(data)
        mm.close()
        return url 

def primitiveFileTruncate(interp, s_frame, w_rcvr, fd, position):
    try:
        ftruncate(fd, position)
    except OSError:
        raise PrimitiveFailedError
    return w_rcvr 

def write_pid_file(pid_file, pid):
    import fcntl
    import stat

    try:
        fd = os.open(pid_file, os.O_RDWR | os.O_CREAT,
                     stat.S_IRUSR | stat.S_IWUSR)
    except OSError as e:
        shell.print_exception(e)
        return -1
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    assert flags != -1
    flags |= fcntl.FD_CLOEXEC
    r = fcntl.fcntl(fd, fcntl.F_SETFD, flags)
    assert r != -1
    # There is no platform independent way to implement fcntl(fd, F_SETLK, &fl)
    # via fcntl.fcntl. So use lockf instead
    try:
        fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB, 0, 0, os.SEEK_SET)
    except IOError:
        r = os.read(fd, 32)
        if r:
            logging.error('already started at pid %s' % common.to_str(r))
        else:
            logging.error('already started')
        os.close(fd)
        return -1
    os.ftruncate(fd, 0)
    os.write(fd, common.to_bytes(str(pid)))
    return 0 

def count(delta, file_path):
    """
    Increments counter file and returns the max number of times the file
    has been modified. Counter data must be in the form:
    concurrent tasks, max concurrent tasks (counter should be initialized to 0,0)

    :param int delta: increment value
    :param str file_path: path to shared counter file
    :return int max concurrent tasks:
    """
    fd = os.open(file_path, os.O_RDWR)
    try:
        fcntl.flock(fd, fcntl.LOCK_EX)
        try:
            s = os.read(fd, 10)
            value, maxValue = list(map(int, s.decode('utf-8').split(',')))
            value += delta
            if value > maxValue: maxValue = value
            os.lseek(fd, 0, 0)
            os.ftruncate(fd, 0)
            os.write(fd, ','.join(map(str, (value, maxValue))).encode('utf-8'))
        finally:
            fcntl.flock(fd, fcntl.LOCK_UN)
    finally:
        os.close(fd)
    return maxValue 

def write_pid_file(pid_file, pid):
    import fcntl
    import stat

    try:
        fd = os.open(pid_file, os.O_RDWR | os.O_CREAT,
                     stat.S_IRUSR | stat.S_IWUSR)
    except OSError as e:
        shell.print_exception(e)
        return -1
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    assert flags != -1
    flags |= fcntl.FD_CLOEXEC
    r = fcntl.fcntl(fd, fcntl.F_SETFD, flags)
    assert r != -1
    # There is no platform independent way to implement fcntl(fd, F_SETLK, &fl)
    # via fcntl.fcntl. So use lockf instead
    try:
        fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB, 0, 0, os.SEEK_SET)
    except IOError:
        r = os.read(fd, 32)
        if r:
            logging.error('already started at pid %s' % common.to_str(r))
        else:
            logging.error('already started')
        os.close(fd)
        return -1
    os.ftruncate(fd, 0)
    os.write(fd, common.to_bytes(str(pid)))
    return 0 

def write_pid_file(pid_file, pid):
    import fcntl
    import stat

    try:
        fd = os.open(pid_file, os.O_RDWR | os.O_CREAT,
                     stat.S_IRUSR | stat.S_IWUSR)
    except OSError as e:
        shell.print_exception(e)
        return -1
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    assert flags != -1
    flags |= fcntl.FD_CLOEXEC
    r = fcntl.fcntl(fd, fcntl.F_SETFD, flags)
    assert r != -1
    # There is no platform independent way to implement fcntl(fd, F_SETLK, &fl)
    # via fcntl.fcntl. So use lockf instead
    try:
        fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB, 0, 0, os.SEEK_SET)
    except IOError:
        r = os.read(fd, 32)
        if r:
            logging.error('already started at pid %s' % common.to_str(r))
        else:
            logging.error('already started')
        os.close(fd)
        return -1
    os.ftruncate(fd, 0)
    os.write(fd, common.to_bytes(str(pid)))
    return 0