SAFE_MACROS: Add memalign()

Signed-off-by: Zeng Linggang <zenglg.jy@cn.fujitsu.com>
read/read02.c: cleanup

* Delete some useless commtents and variable.
* Use SAFE_* macros.
* Some cleanup.

Signed-off-by: Zeng Linggang <zenglg.jy@cn.fujitsu.com>
read/read02.c: add new error number tests

Add EINVAL errnor nuber tests for read(2):
* The file was opened with the O_DIRECT flag, and the alignment of the user
  buffer was not multiples of the logical block size of the file system,
  expect an EINVAL.

* The file was opened with the O_DIRECT flag, and transfer sizes was not
  multiples of the logical block size of the file system, expect an EINVAL.

Signed-off-by: Zeng Linggang <zenglg.jy@cn.fujitsu.com>