--- /dev/null
+#!/usr/bin/env python
+#
+# Copyright (c) 2016 Cisco and/or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+from __future__ import print_function
+import sys
+import os
+import logging
+import collections
+import struct
+import json
+import threading
+import fnmatch
+import weakref
+import atexit
+from cffi import FFI
+import cffi
+
+if sys.version[0] == '2':
+ import Queue as queue
+else:
+ import queue as queue
+
+ffi = FFI()
+ffi.cdef("""
+typedef void (*vac_callback_t)(unsigned char * data, int len);
+typedef void (*vac_error_callback_t)(void *, unsigned char *, int);
+int vac_connect(char * name, char * chroot_prefix, vac_callback_t cb,
+ int rx_qlen);
+int vac_disconnect(void);
+int vac_read(char **data, int *l, unsigned short timeout);
+int vac_write(char *data, int len);
+void vac_free(void * msg);
+
+int vac_get_msg_index(unsigned char * name);
+int vac_msg_table_size(void);
+int vac_msg_table_max_index(void);
+
+void vac_rx_suspend (void);
+void vac_rx_resume (void);
+void vac_set_error_handler(vac_error_callback_t);
+ """)
+
+# Barfs on failure, no need to check success.
+vpp_api = ffi.dlopen('libvppapiclient.so')
+
+
+def vpp_atexit(vpp_weakref):
+ """Clean up VPP connection on shutdown."""
+ vpp_instance = vpp_weakref()
+ if vpp_instance.connected:
+ vpp_instance.logger.debug('Cleaning up VPP on exit')
+ vpp_instance.disconnect()
+
+
+vpp_object = None
+
+
+def vpp_iterator(d):
+ if sys.version[0] == '2':
+ return d.iteritems()
+ else:
+ return d.items()
+
+
+@ffi.callback("void(unsigned char *, int)")
+def vac_callback_sync(data, len):
+ vpp_object.msg_handler_sync(ffi.buffer(data, len))
+
+
+@ffi.callback("void(unsigned char *, int)")
+def vac_callback_async(data, len):
+ vpp_object.msg_handler_async(ffi.buffer(data, len))
+
+
+@ffi.callback("void(void *, unsigned char *, int)")
+def vac_error_handler(arg, msg, msg_len):
+ vpp_object.logger.warning("VPP API client:: %s", ffi.string(msg, msg_len))
+
+
+class Empty(object):
+ pass
+
+
+class FuncWrapper(object):
+ def __init__(self, func):
+ self._func = func
+ self.__name__ = func.__name__
+
+ def __call__(self, **kwargs):
+ return self._func(**kwargs)
+
+
+class VPP():
+ """VPP interface.
+
+ This class provides the APIs to VPP. The APIs are loaded
+ from provided .api.json files and makes functions accordingly.
+ These functions are documented in the VPP .api files, as they
+ are dynamically created.
+
+ Additionally, VPP can send callback messages; this class
+ provides a means to register a callback function to receive
+ these messages in a background thread.
+ """
+ def __init__(self, apifiles=None, testmode=False, async_thread=True,
+ logger=None, loglevel=None,
+ read_timeout=0):
+ """Create a VPP API object.
+
+ apifiles is a list of files containing API
+ descriptions that will be loaded - methods will be
+ dynamically created reflecting these APIs. If not
+ provided this will load the API files from VPP's
+ default install location.
+
+ logger, if supplied, is the logging logger object to log to.
+ loglevel, if supplied, is the log level this logger is set
+ to report at (from the loglevels in the logging module).
+ """
+ global vpp_object
+ vpp_object = self
+
+ if logger is None:
+ logger = logging.getLogger(__name__)
+ if loglevel is not None:
+ logger.setLevel(loglevel)
+
+ self.logger = logger
+
+ self.messages = {}
+ self.id_names = []
+ self.id_msgdef = []
+ self.connected = False
+ self.header = struct.Struct('>HI')
+ self.apifiles = []
+ self.event_callback = None
+ self.message_queue = queue.Queue()
+ self.read_timeout = read_timeout
+ self.vpp_api = vpp_api
+ self.async_thread = async_thread
+
+ if not apifiles:
+ # Pick up API definitions from default directory
+ try:
+ apifiles = self.find_api_files()
+ except RuntimeError:
+ # In test mode we don't care that we can't find the API files
+ if testmode:
+ apifiles = []
+ else:
+ raise
+
+ for file in apifiles:
+ with open(file) as apidef_file:
+ api = json.load(apidef_file)
+ for t in api['types']:
+ self.add_type(t[0], t[1:])
+
+ for m in api['messages']:
+ self.add_message(m[0], m[1:])
+ self.apifiles = apifiles
+
+ # Basic sanity check
+ if len(self.messages) == 0 and not testmode:
+ raise ValueError(1, 'Missing JSON message definitions')
+
+ # Make sure we allow VPP to clean up the message rings.
+ atexit.register(vpp_atexit, weakref.ref(self))
+
+ # Register error handler
+ vpp_api.vac_set_error_handler(vac_error_handler)
+
+ # Support legacy CFFI
+ # from_buffer supported from 1.8.0
+ (major, minor, patch) = [int(s) for s in
+ cffi.__version__.split('.', 3)]
+ if major >= 1 and minor >= 8:
+ self._write = self._write_new_cffi
+ else:
+ self._write = self._write_legacy_cffi
+
+ class ContextId(object):
+ """Thread-safe provider of unique context IDs."""
+ def __init__(self):
+ self.context = 0
+ self.lock = threading.Lock()
+
+ def __call__(self):
+ """Get a new unique (or, at least, not recently used) context."""
+ with self.lock:
+ self.context += 1
+ return self.context
+ get_context = ContextId()
+
+ @classmethod
+ def find_api_dir(cls):
+ """Attempt to find the best directory in which API definition
+ files may reside. If the value VPP_API_DIR exists in the environment
+ then it is first on the search list. If we're inside a recognized
+ location in a VPP source tree (src/scripts and src/vpp-api/python)
+ then entries from there to the likely locations in build-root are
+ added. Finally the location used by system packages is added.
+
+ :returns: A single directory name, or None if no such directory
+ could be found.
+ """
+ dirs = []
+
+ if 'VPP_API_DIR' in os.environ:
+ dirs.append(os.environ['VPP_API_DIR'])
+
+ # perhaps we're in the 'src/scripts' or 'src/vpp-api/python' dir;
+ # in which case, plot a course to likely places in the src tree
+ import __main__ as main
+ if hasattr(main, '__file__'):
+ # get the path of the calling script
+ localdir = os.path.dirname(os.path.realpath(main.__file__))
+ else:
+ # use cwd if there is no calling script
+ localdir = os.getcwd()
+ localdir_s = localdir.split(os.path.sep)
+
+ def dmatch(dir):
+ """Match dir against right-hand components of the script dir"""
+ d = dir.split('/') # param 'dir' assumes a / separator
+ length = len(d)
+ return len(localdir_s) > length and localdir_s[-length:] == d
+
+ def sdir(srcdir, variant):
+ """Build a path from srcdir to the staged API files of
+ 'variant' (typically '' or '_debug')"""
+ # Since 'core' and 'plugin' files are staged
+ # in separate directories, we target the parent dir.
+ return os.path.sep.join((
+ srcdir,
+ 'build-root',
+ 'install-vpp%s-native' % variant,
+ 'vpp',
+ 'share',
+ 'vpp',
+ 'api',
+ ))
+
+ srcdir = None
+ if dmatch('src/scripts'):
+ srcdir = os.path.sep.join(localdir_s[:-2])
+ elif dmatch('src/vpp-api/python'):
+ srcdir = os.path.sep.join(localdir_s[:-3])
+ elif dmatch('test'):
+ # we're apparently running tests
+ srcdir = os.path.sep.join(localdir_s[:-1])
+
+ if srcdir:
+ # we're in the source tree, try both the debug and release
+ # variants.
+ dirs.append(sdir(srcdir, '_debug'))
+ dirs.append(sdir(srcdir, ''))
+
+ # Test for staged copies of the scripts
+ # For these, since we explicitly know if we're running a debug versus
+ # release variant, target only the relevant directory
+ if dmatch('build-root/install-vpp_debug-native/vpp/bin'):
+ srcdir = os.path.sep.join(localdir_s[:-4])
+ dirs.append(sdir(srcdir, '_debug'))
+ if dmatch('build-root/install-vpp-native/vpp/bin'):
+ srcdir = os.path.sep.join(localdir_s[:-4])
+ dirs.append(sdir(srcdir, ''))
+
+ # finally, try the location system packages typically install into
+ dirs.append(os.path.sep.join(('', 'usr', 'share', 'vpp', 'api')))
+
+ # check the directories for existance; first one wins
+ for dir in dirs:
+ if os.path.isdir(dir):
+ return dir
+
+ return None
+
+ @classmethod
+ def find_api_files(cls, api_dir=None, patterns='*'):
+ """Find API definition files from the given directory tree with the
+ given pattern. If no directory is given then find_api_dir() is used
+ to locate one. If no pattern is given then all definition files found
+ in the directory tree are used.
+
+ :param api_dir: A directory tree in which to locate API definition
+ files; subdirectories are descended into.
+ If this is None then find_api_dir() is called to discover it.
+ :param patterns: A list of patterns to use in each visited directory
+ when looking for files.
+ This can be a list/tuple object or a comma-separated string of
+ patterns. Each value in the list will have leading/trialing
+ whitespace stripped.
+ The pattern specifies the first part of the filename, '.api.json'
+ is appended.
+ The results are de-duplicated, thus overlapping patterns are fine.
+ If this is None it defaults to '*' meaning "all API files".
+ :returns: A list of file paths for the API files found.
+ """
+ if api_dir is None:
+ api_dir = cls.find_api_dir()
+ if api_dir is None:
+ raise RuntimeError("api_dir cannot be located")
+
+ if isinstance(patterns, list) or isinstance(patterns, tuple):
+ patterns = [p.strip() + '.api.json' for p in patterns]
+ else:
+ patterns = [p.strip() + '.api.json' for p in patterns.split(",")]
+
+ api_files = []
+ for root, dirnames, files in os.walk(api_dir):
+ # iterate all given patterns and de-dup the result
+ files = set(sum([fnmatch.filter(files, p) for p in patterns], []))
+ for filename in files:
+ api_files.append(os.path.join(root, filename))
+
+ return api_files
+
+ def status(self):
+ """Debug function: report current VPP API status to stdout."""
+ print('Connected') if self.connected else print('Not Connected')
+ print('Read API definitions from', ', '.join(self.apifiles))
+
+ def __struct(self, t, n=None, e=-1, vl=None):
+ """Create a packing structure for a message."""
+ base_types = {'u8': 'B',
+ 'u16': 'H',
+ 'u32': 'I',
+ 'i32': 'i',
+ 'u64': 'Q',
+ 'f64': 'd', }
+
+ if t in base_types:
+ if not vl:
+ if e > 0 and t == 'u8':
+ # Fixed byte array
+ s = struct.Struct('>' + str(e) + 's')
+ return s.size, s
+ if e > 0:
+ # Fixed array of base type
+ s = struct.Struct('>' + base_types[t])
+ return s.size, [e, s]
+ elif e == 0:
+ # Old style variable array
+ s = struct.Struct('>' + base_types[t])
+ return s.size, [-1, s]
+ else:
+ # Variable length array
+ if t == 'u8':
+ s = struct.Struct('>s')
+ return s.size, [vl, s]
+ else:
+ s = struct.Struct('>' + base_types[t])
+ return s.size, [vl, s]
+
+ s = struct.Struct('>' + base_types[t])
+ return s.size, s
+
+ if t in self.messages:
+ size = self.messages[t]['sizes'][0]
+
+ # Return a list in case of array
+ if e > 0 and not vl:
+ return size, [e, lambda self, encode, buf, offset, args: (
+ self.__struct_type(encode, self.messages[t], buf, offset,
+ args))]
+ if vl:
+ return size, [vl, lambda self, encode, buf, offset, args: (
+ self.__struct_type(encode, self.messages[t], buf, offset,
+ args))]
+ elif e == 0:
+ # Old style VLA
+ raise NotImplementedError(1,
+ 'No support for compound types ' + t)
+ return size, lambda self, encode, buf, offset, args: (
+ self.__struct_type(encode, self.messages[t], buf, offset, args)
+ )
+
+ raise ValueError(1, 'Invalid message type: ' + t)
+
+ def __struct_type(self, encode, msgdef, buf, offset, kwargs):
+ """Get a message packer or unpacker."""
+ if encode:
+ return self.__struct_type_encode(msgdef, buf, offset, kwargs)
+ else:
+ return self.__struct_type_decode(msgdef, buf, offset)
+
+ def __struct_type_encode(self, msgdef, buf, offset, kwargs):
+ off = offset
+ size = 0
+
+ for k in kwargs:
+ if k not in msgdef['args']:
+ raise ValueError(1, 'Non existing argument [' + k + ']' +
+ ' used in call to: ' +
+ self.id_names[kwargs['_vl_msg_id']] + '()')
+
+ for k, v in vpp_iterator(msgdef['args']):
+ off += size
+ if k in kwargs:
+ if type(v) is list:
+ if callable(v[1]):
+ e = kwargs[v[0]] if v[0] in kwargs else v[0]
+ if e != len(kwargs[k]):
+ raise (ValueError(1,
+ 'Input list length mismatch: '
+ '%s (%s != %s)' %
+ (k, e, len(kwargs[k]))))
+ size = 0
+ for i in range(e):
+ size += v[1](self, True, buf, off + size,
+ kwargs[k][i])
+ else:
+ if v[0] in kwargs:
+ kwargslen = kwargs[v[0]]
+ if kwargslen != len(kwargs[k]):
+ raise ValueError(1,
+ 'Input list length mismatch:'
+ ' %s (%s != %s)' %
+ (k, kwargslen,
+ len(kwargs[k])))
+ else:
+ kwargslen = len(kwargs[k])
+ if v[1].size == 1:
+ buf[off:off + kwargslen] = bytearray(kwargs[k])
+ size = kwargslen
+ else:
+ size = 0
+ for i in kwargs[k]:
+ v[1].pack_into(buf, off + size, i)
+ size += v[1].size
+ else:
+ if callable(v):
+ size = v(self, True, buf, off, kwargs[k])
+ else:
+ if type(kwargs[k]) is str and v.size < len(kwargs[k]):
+ raise ValueError(1,
+ 'Input list length mismatch: '
+ '%s (%s < %s)' %
+ (k, v.size, len(kwargs[k])))
+ v.pack_into(buf, off, kwargs[k])
+ size = v.size
+ else:
+ size = v.size if not type(v) is list else 0
+
+ return off + size - offset
+
+ def __getitem__(self, name):
+ if name in self.messages:
+ return self.messages[name]
+ return None
+
+ def get_size(self, sizes, kwargs):
+ total_size = sizes[0]
+ for e in sizes[1]:
+ if e in kwargs and type(kwargs[e]) is list:
+ total_size += len(kwargs[e]) * sizes[1][e]
+ return total_size
+
+ def encode(self, msgdef, kwargs):
+ # Make suitably large buffer
+ size = self.get_size(msgdef['sizes'], kwargs)
+ buf = bytearray(size)
+ offset = 0
+ size = self.__struct_type(True, msgdef, buf, offset, kwargs)
+ return buf[:offset + size]
+
+ def decode(self, msgdef, buf):
+ return self.__struct_type(False, msgdef, buf, 0, None)[1]
+
+ def __struct_type_decode(self, msgdef, buf, offset):
+ res = []
+ off = offset
+ size = 0
+ for k, v in vpp_iterator(msgdef['args']):
+ off += size
+ if type(v) is list:
+ lst = []
+ if callable(v[1]): # compound type
+ size = 0
+ if v[0] in msgdef['args']: # vla
+ e = res[v[2]]
+ else: # fixed array
+ e = v[0]
+ res.append(lst)
+ for i in range(e):
+ (s, l) = v[1](self, False, buf, off + size, None)
+ lst.append(l)
+ size += s
+ continue
+ if v[1].size == 1:
+ if type(v[0]) is int:
+ size = len(buf) - off
+ else:
+ size = res[v[2]]
+ res.append(buf[off:off + size])
+ else:
+ e = v[0] if type(v[0]) is int else res[v[2]]
+ if e == -1:
+ e = (len(buf) - off) / v[1].size
+ lst = []
+ res.append(lst)
+ size = 0
+ for i in range(e):
+ lst.append(v[1].unpack_from(buf, off + size)[0])
+ size += v[1].size
+ else:
+ if callable(v):
+ size = 0
+ (s, l) = v(self, False, buf, off, None)
+ res.append(l)
+ size += s
+ else:
+ res.append(v.unpack_from(buf, off)[0])
+ size = v.size
+
+ return off + size - offset, msgdef['return_tuple']._make(res)
+
+ def ret_tup(self, name):
+ if name in self.messages and 'return_tuple' in self.messages[name]:
+ return self.messages[name]['return_tuple']
+ return None
+
+ def duplicate_check_ok(self, name, msgdef):
+ crc = None
+ for c in msgdef:
+ if type(c) is dict and 'crc' in c:
+ crc = c['crc']
+ break
+ if crc:
+ # We can get duplicates because of imports
+ if crc == self.messages[name]['crc']:
+ return True
+ return False
+
+ def add_message(self, name, msgdef, typeonly=False):
+ if name in self.messages:
+ if typeonly:
+ if self.duplicate_check_ok(name, msgdef):
+ return
+ raise ValueError('Duplicate message name: ' + name)
+
+ args = collections.OrderedDict()
+ argtypes = collections.OrderedDict()
+ fields = []
+ msg = {}
+ total_size = 0
+ sizes = {}
+ for i, f in enumerate(msgdef):
+ if type(f) is dict and 'crc' in f:
+ msg['crc'] = f['crc']
+ continue
+ field_type = f[0]
+ field_name = f[1]
+ if len(f) == 3 and f[2] == 0 and i != len(msgdef) - 2:
+ raise ValueError('Variable Length Array must be last: ' + name)
+ size, s = self.__struct(*f)
+ args[field_name] = s
+ if type(s) == list and type(s[0]) == int and \
+ type(s[1]) == struct.Struct:
+ if s[0] < 0:
+ sizes[field_name] = size
+ else:
+ sizes[field_name] = size
+ total_size += s[0] * size
+ else:
+ sizes[field_name] = size
+ total_size += size
+
+ argtypes[field_name] = field_type
+ if len(f) == 4: # Find offset to # elements field
+ idx = list(args.keys()).index(f[3]) - i
+ args[field_name].append(idx)
+ fields.append(field_name)
+ msg['return_tuple'] = collections.namedtuple(name, fields,
+ rename=True)
+ self.messages[name] = msg
+ self.messages[name]['args'] = args
+ self.messages[name]['argtypes'] = argtypes
+ self.messages[name]['typeonly'] = typeonly
+ self.messages[name]['sizes'] = [total_size, sizes]
+ return self.messages[name]
+
+ def add_type(self, name, typedef):
+ return self.add_message('vl_api_' + name + '_t', typedef,
+ typeonly=True)
+
+ def make_function(self, name, i, msgdef, multipart, async):
+ if (async):
+ def f(**kwargs):
+ return self._call_vpp_async(i, msgdef, **kwargs)
+ else:
+ def f(**kwargs):
+ return self._call_vpp(i, msgdef, multipart, **kwargs)
+ args = self.messages[name]['args']
+ argtypes = self.messages[name]['argtypes']
+ f.__name__ = str(name)
+ f.__doc__ = ", ".join(["%s %s" %
+ (argtypes[k], k) for k in args.keys()])
+ return f
+
+ @property
+ def api(self):
+ if not hasattr(self, "_api"):
+ raise Exception("Not connected, api definitions not available")
+ return self._api
+
+ def _register_functions(self, async=False):
+ self.id_names = [None] * (self.vpp_dictionary_maxid + 1)
+ self.id_msgdef = [None] * (self.vpp_dictionary_maxid + 1)
+ self._api = Empty()
+ for name, msgdef in vpp_iterator(self.messages):
+ if self.messages[name]['typeonly']:
+ continue
+ crc = self.messages[name]['crc']
+ n = name + '_' + crc[2:]
+ i = vpp_api.vac_get_msg_index(n.encode())
+ if i > 0:
+ self.id_msgdef[i] = msgdef
+ self.id_names[i] = name
+ multipart = True if name.find('_dump') > 0 else False
+ f = self.make_function(name, i, msgdef, multipart, async)
+ setattr(self._api, name, FuncWrapper(f))
+ else:
+ self.logger.debug(
+ 'No such message type or failed CRC checksum: %s', n)
+
+ def _write_new_cffi(self, buf):
+ """Send a binary-packed message to VPP."""
+ if not self.connected:
+ raise IOError(1, 'Not connected')
+ return vpp_api.vac_write(ffi.from_buffer(buf), len(buf))
+
+ def _write_legacy_cffi(self, buf):
+ """Send a binary-packed message to VPP."""
+ if not self.connected:
+ raise IOError(1, 'Not connected')
+ return vpp_api.vac_write(bytes(buf), len(buf))
+
+ def _read(self):
+ if not self.connected:
+ raise IOError(1, 'Not connected')
+ mem = ffi.new("char **")
+ size = ffi.new("int *")
+ rv = vpp_api.vac_read(mem, size, self.read_timeout)
+ if rv:
+ raise IOError(rv, 'vac_read failed')
+ msg = bytes(ffi.buffer(mem[0], size[0]))
+ vpp_api.vac_free(mem[0])
+ return msg
+
+ def connect_internal(self, name, msg_handler, chroot_prefix, rx_qlen,
+ async):
+ pfx = chroot_prefix.encode() if chroot_prefix else ffi.NULL
+ rv = vpp_api.vac_connect(name.encode(), pfx, msg_handler, rx_qlen)
+ if rv != 0:
+ raise IOError(2, 'Connect failed')
+ self.connected = True
+
+ self.vpp_dictionary_maxid = vpp_api.vac_msg_table_max_index()
+ self._register_functions(async=async)
+
+ # Initialise control ping
+ crc = self.messages['control_ping']['crc']
+ self.control_ping_index = vpp_api.vac_get_msg_index(
+ ('control_ping' + '_' + crc[2:]).encode())
+ self.control_ping_msgdef = self.messages['control_ping']
+ if self.async_thread:
+ self.event_thread = threading.Thread(
+ target=self.thread_msg_handler)
+ self.event_thread.daemon = True
+ self.event_thread.start()
+ return rv
+
+ def connect(self, name, chroot_prefix=None, async=False, rx_qlen=32):
+ """Attach to VPP.
+
+ name - the name of the client.
+ chroot_prefix - if VPP is chroot'ed, the prefix of the jail
+ async - if true, messages are sent without waiting for a reply
+ rx_qlen - the length of the VPP message receive queue between
+ client and server.
+ """
+ msg_handler = vac_callback_sync if not async else vac_callback_async
+ return self.connect_internal(name, msg_handler, chroot_prefix, rx_qlen,
+ async)
+
+ def connect_sync(self, name, chroot_prefix=None, rx_qlen=32):
+ """Attach to VPP in synchronous mode. Application must poll for events.
+
+ name - the name of the client.
+ chroot_prefix - if VPP is chroot'ed, the prefix of the jail
+ rx_qlen - the length of the VPP message receive queue between
+ client and server.
+ """
+
+ return self.connect_internal(name, ffi.NULL, chroot_prefix, rx_qlen,
+ async=False)
+
+ def disconnect(self):
+ """Detach from VPP."""
+ rv = vpp_api.vac_disconnect()
+ self.connected = False
+ self.message_queue.put("terminate event thread")
+ return rv
+
+ def msg_handler_sync(self, msg):
+ """Process an incoming message from VPP in sync mode.
+
+ The message may be a reply or it may be an async notification.
+ """
+ r = self.decode_incoming_msg(msg)
+ if r is None:
+ return
+
+ # If we have a context, then use the context to find any
+ # request waiting for a reply
+ context = 0
+ if hasattr(r, 'context') and r.context > 0:
+ context = r.context
+
+ if context == 0:
+ # No context -> async notification that we feed to the callback
+ self.message_queue.put_nowait(r)
+ else:
+ raise IOError(2, 'RPC reply message received in event handler')
+
+ def decode_incoming_msg(self, msg):
+ if not msg:
+ self.logger.warning('vpp_api.read failed')
+ return
+
+ i, ci = self.header.unpack_from(msg, 0)
+ if self.id_names[i] == 'rx_thread_exit':
+ return
+
+ #
+ # Decode message and returns a tuple.
+ #
+ msgdef = self.id_msgdef[i]
+ if not msgdef:
+ raise IOError(2, 'Reply message undefined')
+
+ r = self.decode(msgdef, msg)
+
+ return r
+
+ def msg_handler_async(self, msg):
+ """Process a message from VPP in async mode.
+
+ In async mode, all messages are returned to the callback.
+ """
+ r = self.decode_incoming_msg(msg)
+ if r is None:
+ return
+
+ msgname = type(r).__name__
+
+ if self.event_callback:
+ self.event_callback(msgname, r)
+
+ def _control_ping(self, context):
+ """Send a ping command."""
+ self._call_vpp_async(self.control_ping_index,
+ self.control_ping_msgdef,
+ context=context)
+
+ def _call_vpp(self, i, msgdef, multipart, **kwargs):
+ """Given a message, send the message and await a reply.
+
+ msgdef - the message packing definition
+ i - the message type index
+ multipart - True if the message returns multiple
+ messages in return.
+ context - context number - chosen at random if not
+ supplied.
+ The remainder of the kwargs are the arguments to the API call.
+
+ The return value is the message or message array containing
+ the response. It will raise an IOError exception if there was
+ no response within the timeout window.
+ """
+
+ if 'context' not in kwargs:
+ context = self.get_context()
+ kwargs['context'] = context
+ else:
+ context = kwargs['context']
+ kwargs['_vl_msg_id'] = i
+ b = self.encode(msgdef, kwargs)
+
+ vpp_api.vac_rx_suspend()
+ self._write(b)
+
+ if multipart:
+ # Send a ping after the request - we use its response
+ # to detect that we have seen all results.
+ self._control_ping(context)
+
+ # Block until we get a reply.
+ rl = []
+ while (True):
+ msg = self._read()
+ if not msg:
+ raise IOError(2, 'VPP API client: read failed')
+
+ r = self.decode_incoming_msg(msg)
+ msgname = type(r).__name__
+ if context not in r or r.context == 0 or context != r.context:
+ self.message_queue.put_nowait(r)
+ continue
+
+ if not multipart:
+ rl = r
+ break
+ if msgname == 'control_ping_reply':
+ break
+
+ rl.append(r)
+
+ vpp_api.vac_rx_resume()
+
+ return rl
+
+ def _call_vpp_async(self, i, msgdef, **kwargs):
+ """Given a message, send the message and await a reply.
+
+ msgdef - the message packing definition
+ i - the message type index
+ context - context number - chosen at random if not
+ supplied.
+ The remainder of the kwargs are the arguments to the API call.
+ """
+ if 'context' not in kwargs:
+ context = self.get_context()
+ kwargs['context'] = context
+ else:
+ context = kwargs['context']
+ kwargs['_vl_msg_id'] = i
+ b = self.encode(msgdef, kwargs)
+
+ self._write(b)
+
+ def register_event_callback(self, callback):
+ """Register a callback for async messages.
+
+ This will be called for async notifications in sync mode,
+ and all messages in async mode. In sync mode, replies to
+ requests will not come here.
+
+ callback is a fn(msg_type_name, msg_type) that will be
+ called when a message comes in. While this function is
+ executing, note that (a) you are in a background thread and
+ may wish to use threading.Lock to protect your datastructures,
+ and (b) message processing from VPP will stop (so if you take
+ a long while about it you may provoke reply timeouts or cause
+ VPP to fill the RX buffer). Passing None will disable the
+ callback.
+ """
+ self.event_callback = callback
+
+ def thread_msg_handler(self):
+ """Python thread calling the user registerd message handler.
+
+ This is to emulate the old style event callback scheme. Modern
+ clients should provide their own thread to poll the event
+ queue.
+ """
+ while True:
+ r = self.message_queue.get()
+ if r == "terminate event thread":
+ break
+ msgname = type(r).__name__
+ if self.event_callback:
+ self.event_callback(msgname, r)
+
+
+# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4
Code Review / vpp.git / blobdiff