PR 67585 Handle EINTR

PR 67585 Handle EINTR

Many POSIX systems have the bad habit of not restarting interrupted
syscalls. On these systems it's up to the user to check for an error
with errno == EINTR and restart manually. This patch does this for
libgfortran, so that GFortran users don't have to do it.

2016-10-09  Janne Blomqvist  <jb@gcc.gnu.org>

        PR libfortran/67585
        * io/io.h: TEMP_FAILURE_RETRY: Define macro if not found.
        * io/unix.c (raw_read): Handle EINTR.
        (raw_write): Check for return value -1.
        (raw_seek): Handle EINTR.
        (raw_tell): Likewise.
        (raw_size): Likewise.
        (raw_truncate): Likewise.
        (raw_close): Likewise.
        (buf_flush): Call raw_seek instead of lseek.
        (buf_read): Likewise.
        (buf_write): Likewise.
        (fd_to_stream): Handle EINTR.
        (tempfile_open): Likewise.
        (regular_file2): Likewise.
        (compare_file_filename): Likewise.
        (find_file): Likewise.
        (inquire_sequential): Likewise.
        (inquire_direct): Likewise.
        (inquire_formatted): Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@240902 138bc75d-0d04-0410-961f-82ee72b054a4