Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 71 insertions, 0 deletions

diff --git a/scripts/qapi/source.py b/scripts/qapi/source.py
new file mode 100644
index 000000000..04193cc96
--- /dev/null
+++ b/scripts/qapi/source.py
@@ -0,0 +1,71 @@
+#
+# QAPI frontend source file info
+#
+# Copyright (c) 2019 Red Hat Inc.
+#
+# Authors:
+#  Markus Armbruster <armbru@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2.
+# See the COPYING file in the top-level directory.
+
+import copy
+from typing import List, Optional, TypeVar
+
+
+class QAPISchemaPragma:
+    # Replace with @dataclass in Python 3.7+
+    # pylint: disable=too-few-public-methods
+
+    def __init__(self) -> None:
+        # Are documentation comments required?
+        self.doc_required = False
+        # Commands whose names may use '_'
+        self.command_name_exceptions: List[str] = []
+        # Commands allowed to return a non-dictionary
+        self.command_returns_exceptions: List[str] = []
+        # Types whose member names may violate case conventions
+        self.member_name_exceptions: List[str] = []
+
+
+class QAPISourceInfo:
+    T = TypeVar('T', bound='QAPISourceInfo')
+
+    def __init__(self, fname: str, parent: Optional['QAPISourceInfo']):
+        self.fname = fname
+        self.line = 1
+        self.parent = parent
+        self.pragma: QAPISchemaPragma = (
+            parent.pragma if parent else QAPISchemaPragma()
+        )
+        self.defn_meta: Optional[str] = None
+        self.defn_name: Optional[str] = None
+
+    def set_defn(self, meta: str, name: str) -> None:
+        self.defn_meta = meta
+        self.defn_name = name
+
+    def next_line(self: T) -> T:
+        info = copy.copy(self)
+        info.line += 1
+        return info
+
+    def loc(self) -> str:
+        return f"{self.fname}:{self.line}"
+
+    def in_defn(self) -> str:
+        if self.defn_name:
+            return "%s: In %s '%s':\n" % (self.fname,
+                                          self.defn_meta, self.defn_name)
+        return ''
+
+    def include_path(self) -> str:
+        ret = ''
+        parent = self.parent
+        while parent:
+            ret = 'In file included from %s:\n' % parent.loc() + ret
+            parent = parent.parent
+        return ret
+
+    def __str__(self) -> str:
+        return self.include_path() + self.in_defn() + self.loc()