comparison mercurial/posix.py @ 30445:1ce4c2062ab0

posix: simplify checkexec check

Use a slightly simpler logic that in some cases can avoid an unnecessary chmod
and stat.

Instead of flipping the X bits, make it more clear that we rely on no X bits
being set on initial file creation, and that at least some of them stick after
they all have been set.

30444:b1ce25a40826

        if not os.path.isdir(cachedir):
            cachedir = path
        fh, fn = tempfile.mkstemp(dir=cachedir, prefix='hg-checkexec-')
        try:
            os.close(fh)
            m = os.stat(fn).st_mode & 0o777
            new_file_has_exec = m & EXECFLAGS
            os.chmod(fn, m ^ EXECFLAGS)
            exec_flags_cannot_flip = ((os.stat(fn).st_mode & 0o777) == m)
        finally:
            os.unlink(fn)
    except (IOError, OSError):
        # we don't care, the user probably won't be able to commit anyway
        return False
    return not (new_file_has_exec or exec_flags_cannot_flip)

def checklink(path):
    """check whether the given path is on a symlink-capable filesystem"""
    # mktemp is not racy because symlink creation will fail if the
    # file already exists

30445:1ce4c2062ab0

        if not os.path.isdir(cachedir):
            cachedir = path
        fh, fn = tempfile.mkstemp(dir=cachedir, prefix='hg-checkexec-')
        try:
            os.close(fh)
            m = os.stat(fn).st_mode
            if m & EXECFLAGS:
                return False
            os.chmod(fn, m & 0o777 | EXECFLAGS)
            return os.stat(fn).st_mode & EXECFLAGS
        finally:
            os.unlink(fn)
    except (IOError, OSError):
        # we don't care, the user probably won't be able to commit anyway
        return False

def checklink(path):
    """check whether the given path is on a symlink-capable filesystem"""
    # mktemp is not racy because symlink creation will fail if the
    # file already exists