Add new C API

Change-Id: I717ce3cd7c867c155de149ec56623269d26d0ff7
Signed-off-by: Klement Sekera <ksekera@cisco.com>

1 files changed, 303 insertions, 0 deletions

diff --git a/src/vpp-api/vapi/vapi_json_parser.py b/src/vpp-api/vapi/vapi_json_parser.py
new file mode 100644
index 00000000000..57a2238322b
--- /dev/null
+++ b/src/vpp-api/vapi/vapi_json_parser.py
@@ -0,0 +1,303 @@
+#!/usr/bin/env python3
+
+import json
+
+
+def msg_is_reply(name):
+    return name.endswith('_reply') or name.endswith('_details') \
+        or name.endswith('_event') or name.endswith('_counters')
+
+
+class ParseError (Exception):
+    pass
+
+
+magic_prefix = "vl_api_"
+magic_suffix = "_t"
+
+
+def remove_magic(what):
+    if what.startswith(magic_prefix) and what.endswith(magic_suffix):
+        return what[len(magic_prefix): - len(magic_suffix)]
+    return what
+
+
+class Field:
+
+    def __init__(
+            self,
+            field_name,
+            field_type,
+            array_len=None,
+            nelem_field=None):
+        self.name = field_name
+        self.type = field_type
+        self.len = array_len
+        self.nelem_field = nelem_field
+
+    def __str__(self):
+        if self.len is None:
+            return "name: %s, type: %s" % (self.name, self.type)
+        elif self.len > 0:
+            return "name: %s, type: %s, length: %s" % (self.name, self.type,
+                                                       self.len)
+        else:
+            return ("name: %s, type: %s, variable length stored in: %s" %
+                    (self.name, self.type, self.nelem_field))
+
+
+class Type:
+    def __init__(self, name):
+        self.name = name
+
+
+class SimpleType (Type):
+
+    def __init__(self, name):
+        super().__init__(name)
+
+    def __str__(self):
+        return self.name
+
+
+def get_msg_header_defs(struct_type_class, field_class, typedict):
+    return [
+        struct_type_class(['msg_header1_t',
+                           ['u16', '_vl_msg_id'],
+                           ['u32', 'context'],
+                           ],
+                          typedict, field_class
+                          ),
+        struct_type_class(['msg_header2_t',
+                           ['u16', '_vl_msg_id'],
+                           ['u32', 'client_index'],
+                           ['u32', 'context'],
+                           ],
+                          typedict, field_class
+                          ),
+    ]
+
+
+class Struct:
+
+    def __init__(self, name, fields):
+        self.name = name
+        self.fields = fields
+        self.field_names = [n.name for n in self.fields]
+
+
+class Message:
+
+    def __init__(self, logger, definition, typedict,
+                 struct_type_class, simple_type_class, field_class):
+        self.logger = logger
+        m = definition
+        logger.debug("Parsing message definition `%s'" % m)
+        name = m[0]
+        self.name = name
+        logger.debug("Message name is `%s'" % name)
+        ignore = True
+        self.header = None
+        fields = []
+        for header in get_msg_header_defs(struct_type_class, field_class,
+                                          typedict):
+            logger.debug("Probing header `%s'" % header.name)
+            if header.is_part_of_def(m[1:]):
+                self.header = header
+                logger.debug("Found header `%s'" % header.name)
+                fields.append(field_class(field_name='header',
+                                          field_type=self.header))
+                ignore = False
+                break
+        if ignore and not msg_is_reply(name):
+            raise ParseError("While parsing message `%s': could not find all "
+                             "common header fields" % name)
+        for field in m[1:]:
+            if len(field) == 1 and 'crc' in field:
+                self.crc = field['crc']
+                logger.debug("Found CRC `%s'" % self.crc)
+                continue
+            else:
+                field_type = field[0]
+                if field_type in typedict:
+                    field_type = typedict[field_type]
+                else:
+                    field_type = typedict[remove_magic(field_type)]
+                if len(field) == 2:
+                    if self.header is not None and\
+                            self.header.has_field(field[1]):
+                        continue
+                    p = field_class(field_name=field[1],
+                                    field_type=field_type)
+                elif len(field) == 3:
+                    if field[2] == 0:
+                        raise ParseError(
+                            "While parsing message `%s': variable length "
+                            "array `%s' doesn't have reference to member "
+                            "containing the actual length" % (
+                                name, field[1]))
+                    p = field_class(
+                        field_name=field[1],
+                        field_type=field_type,
+                        array_len=field[2])
+                elif len(field) == 4:
+                    nelem_field = None
+                    for f in fields:
+                        if f.name == field[3]:
+                            nelem_field = f
+                    if nelem_field is None:
+                        raise ParseError(
+                            "While parsing message `%s': couldn't find "
+                            "variable length array `%s' member containing "
+                            "the actual length `%s'" % (
+                                name, field[1], field[3]))
+                    p = field_class(
+                        field_name=field[1],
+                        field_type=field_type,
+                        array_len=field[2],
+                        nelem_field=nelem_field)
+                else:
+                    raise Exception("Don't know how to parse message "
+                                    "definition for message `%s': `%s'" %
+                                    (m, m[1:]))
+                logger.debug("Parsed field `%s'" % p)
+                fields.append(p)
+        self.fields = fields
+
+    def is_dump(self):
+        return self.name.endswith('_dump')
+
+    def is_reply(self):
+        return msg_is_reply(self.name)
+
+
+class StructType (Type, Struct):
+
+    def __init__(self, definition, typedict, field_class):
+        t = definition
+        name = t[0]
+        fields = []
+        for field in t[1:]:
+            if len(field) == 1 and 'crc' in field:
+                self.crc = field['crc']
+                continue
+            elif len(field) == 2:
+                p = field_class(field_name=field[1],
+                                field_type=typedict[field[0]])
+            elif len(field) == 3:
+                if field[2] == 0:
+                    raise ParseError("While parsing type `%s': array `%s' has "
+                                     "variable length" % (name, field[1]))
+                p = field_class(field_name=field[1],
+                                field_type=typedict[field[0]],
+                                array_len=field[2])
+            else:
+                raise ParseError(
+                    "Don't know how to parse type definition for "
+                    "type `%s': `%s'" % (t, t[1:]))
+            fields.append(p)
+        Type.__init__(self, name)
+        Struct.__init__(self, name, fields)
+
+    def has_field(self, name):
+        return name in self.field_names
+
+    def is_part_of_def(self, definition):
+        for idx in range(len(self.fields)):
+            field = definition[idx]
+            p = self.fields[idx]
+            if field[1] != p.name:
+                return False
+            if field[0] != p.type.name:
+                raise ParseError(
+                    "Unexpected field type `%s' (should be `%s'), "
+                    "while parsing msg/def/field `%s/%s/%s'" %
+                    (field[0], p.type, p.name, definition, field))
+        return True
+
+
+class JsonParser:
+    def __init__(self, logger, files, simple_type_class=SimpleType,
+                 struct_type_class=StructType, field_class=Field,
+                 message_class=Message):
+        self.messages = {}
+        self.types = {
+            x: simple_type_class(x) for x in [
+                'i8', 'i16', 'i32', 'i64',
+                'u8', 'u16', 'u32', 'u64',
+                'f64'
+            ]
+        }
+
+        self.simple_type_class = simple_type_class
+        self.struct_type_class = struct_type_class
+        self.field_class = field_class
+        self.message_class = message_class
+
+        self.exceptions = []
+        self.json_files = []
+        self.types_by_json = {}
+        self.messages_by_json = {}
+        self.logger = logger
+        for f in files:
+            self.parse_json_file(f)
+        self.finalize_parsing()
+
+    def parse_json_file(self, path):
+        self.logger.info("Parsing json api file: `%s'" % path)
+        self.json_files.append(path)
+        self.types_by_json[path] = {}
+        self.messages_by_json[path] = {}
+        with open(path) as f:
+            j = json.load(f)
+            for t in j['types']:
+                try:
+                    type_ = self.struct_type_class(t, self.types,
+                                                   self.field_class)
+                    if type_.name in self.types:
+                        raise ParseError("Duplicate type `%s'" % type_.name)
+                except ParseError as e:
+                    self.exceptions.append(e)
+                    continue
+                self.types[type_.name] = type_
+                self.types_by_json[path][type_.name] = type_
+            for m in j['messages']:
+                try:
+                    msg = self.message_class(self.logger, m, self.types,
+                                             self.struct_type_class,
+                                             self.simple_type_class,
+                                             self.field_class)
+                    if msg.name in self.messages:
+                        raise ParseError("Duplicate message `%s'" % msg.name)
+                except ParseError as e:
+                    self.exceptions.append(e)
+                    continue
+                self.messages[msg.name] = msg
+                self.messages_by_json[path][msg.name] = msg
+
+    def get_reply(self, message):
+        if self.messages[message].is_dump():
+            return self.messages["%s_details" % message[:-len("_dump")]]
+        return self.messages["%s_reply" % message]
+
+    def finalize_parsing(self):
+        if len(self.messages) == 0:
+            for e in self.exceptions:
+                self.logger.error(e)
+            raise Exception("No messages parsed.")
+        for jn, j in self.messages_by_json.items():
+            remove = []
+            for n, m in j.items():
+                try:
+                    if not m.is_reply():
+                        try:
+                            m.reply = self.get_reply(n)
+                        except:
+                            raise ParseError(
+                                "Cannot find reply to message `%s'" % n)
+                except ParseError as e:
+                    self.exceptions.append(e)
+                    remove.append(n)
+
+            self.messages_by_json[jn] = {
+                k: v for k, v in j.items() if k not in remove}