split platform

lib/python3.5/site-packages/OpenSSL/_util.py

@@ -0,0 +1,127 @@
+from warnings import warn
+import sys
+
+from six import PY3, binary_type, text_type
+
+from cryptography.hazmat.bindings.openssl.binding import Binding
+binding = Binding()
+ffi = binding.ffi
+lib = binding.lib
+
+
+
+def text(charp):
+    """
+    Get a native string type representing of the given CFFI ``char*`` object.
+
+    :param charp: A C-style string represented using CFFI.
+
+    :return: :class:`str`
+    """
+    if not charp:
+        return ""
+    return native(ffi.string(charp))
+
+
+
+def exception_from_error_queue(exception_type):
+    """
+    Convert an OpenSSL library failure into a Python exception.
+
+    When a call to the native OpenSSL library fails, this is usually signalled
+    by the return value, and an error code is stored in an error queue
+    associated with the current thread. The err library provides functions to
+    obtain these error codes and textual error messages.
+    """
+
+    errors = []
+
+    while True:
+        error = lib.ERR_get_error()
+        if error == 0:
+            break
+        errors.append((
+                text(lib.ERR_lib_error_string(error)),
+                text(lib.ERR_func_error_string(error)),
+                text(lib.ERR_reason_error_string(error))))
+
+    raise exception_type(errors)
+
+
+
+def native(s):
+    """
+    Convert :py:class:`bytes` or :py:class:`unicode` to the native
+    :py:class:`str` type, using UTF-8 encoding if conversion is necessary.
+
+    :raise UnicodeError: The input string is not UTF-8 decodeable.
+
+    :raise TypeError: The input is neither :py:class:`bytes` nor
+        :py:class:`unicode`.
+    """
+    if not isinstance(s, (binary_type, text_type)):
+        raise TypeError("%r is neither bytes nor unicode" % s)
+    if PY3:
+        if isinstance(s, binary_type):
+            return s.decode("utf-8")
+    else:
+        if isinstance(s, text_type):
+            return s.encode("utf-8")
+    return s
+
+
+
+def path_string(s):
+    """
+    Convert a Python string to a :py:class:`bytes` string identifying the same
+    path and which can be passed into an OpenSSL API accepting a filename.
+
+    :param s: An instance of :py:class:`bytes` or :py:class:`unicode`.
+
+    :return: An instance of :py:class:`bytes`.
+    """
+    if isinstance(s, binary_type):
+        return s
+    elif isinstance(s, text_type):
+        return s.encode(sys.getfilesystemencoding())
+    else:
+        raise TypeError("Path must be represented as bytes or unicode string")
+
+
+if PY3:
+    def byte_string(s):
+        return s.encode("charmap")
+else:
+    def byte_string(s):
+        return s
+
+
+# A marker object to observe whether some optional arguments are passed any
+# value or not.
+UNSPECIFIED = object()
+
+_TEXT_WARNING = (
+    text_type.__name__ + " for {0} is no longer accepted, use bytes"
+)
+
+def text_to_bytes_and_warn(label, obj):
+    """
+    If ``obj`` is text, emit a warning that it should be bytes instead and try
+    to convert it to bytes automatically.
+
+    :param str label: The name of the parameter from which ``obj`` was taken
+        (so a developer can easily find the source of the problem and correct
+        it).
+
+    :return: If ``obj`` is the text string type, a ``bytes`` object giving the
+        UTF-8 encoding of that text is returned.  Otherwise, ``obj`` itself is
+        returned.
+    """
+    if isinstance(obj, text_type):
+        warn(
+            _TEXT_WARNING.format(label),
+            category=DeprecationWarning,
+            stacklevel=3
+        )
+        return obj.encode('utf-8')
+    return obj