1 files changed, 70 insertions, 0 deletions
diff --git a/ouroboros/_qosspec.py b/ouroboros/_qosspec.py
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+++ b/ouroboros/_qosspec.py
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+#
+# Ouroboros - Copyright (C) 2016 - 2026
+#
+# Internal helpers for translating QoSSpec <-> CFFI qosspec_t.
+#
+#    Dimitri Staessens <dimitri@ouroboros.rocks>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public License
+# version 2.1 as published by the Free Software Foundation.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., http://www.fsf.org/about/contact/.
+#
+
+"""Shared QoSSpec <-> qosspec_t conversion helpers.
+
+dev.py and irm.py each link against their own CFFI extension module
+(``_ouroboros_dev_cffi`` and ``_ouroboros_irm_cffi``), so they each
+have their own ``ffi`` instance and their own ``qosspec_t`` type.
+CFFI types are not interchangeable across modules, so these helpers
+take the caller's ``ffi`` instance as a parameter.
+"""
+
+from __future__ import annotations
+
+from typing import Optional
+
+from ouroboros.qos import QoSSpec
+
+
+def qos_to_qosspec(ffi, qos: Optional[QoSSpec]):
+    """Convert a :class:`QoSSpec` to a freshly-allocated ``qosspec_t *``.
+
+    Returns ``ffi.NULL`` when *qos* is ``None``.
+    """
+    if qos is None:
+        return ffi.NULL
+    return ffi.new("qosspec_t *",
+                   [qos.service,
+                    qos.delay,
+                    qos.bandwidth,
+                    qos.availability,
+                    qos.loss,
+                    qos.ber,
+                    qos.max_gap,
+                    qos.timeout])
+
+
+def qosspec_to_qos(ffi, _qos) -> Optional[QoSSpec]:
+    """Convert a ``qosspec_t *`` back to a :class:`QoSSpec`.
+
+    Returns ``None`` when *_qos* is ``ffi.NULL``.
+    """
+    if _qos == ffi.NULL:
+        return None
+    return QoSSpec(service=_qos.service,
+                   delay=_qos.delay,
+                   bandwidth=_qos.bandwidth,
+                   availability=_qos.availability,
+                   loss=_qos.loss,
+                   ber=_qos.ber,
+                   max_gap=_qos.max_gap,
+                   timeout=_qos.timeout)