diff options
Diffstat (limited to 'test/vpp_pg_interface.py')
-rw-r--r-- | test/vpp_pg_interface.py | 103 |
1 files changed, 57 insertions, 46 deletions
diff --git a/test/vpp_pg_interface.py b/test/vpp_pg_interface.py index d6e6684993c..4707f0b7fdf 100644 --- a/test/vpp_pg_interface.py +++ b/test/vpp_pg_interface.py @@ -16,6 +16,11 @@ from scapy.utils6 import in6_getnsma, in6_getnsmac, in6_ismaddr from scapy.utils import inet_pton, inet_ntop +class CaptureTimeoutError(Exception): + """ Exception raised if capture or packet doesn't appear within timeout """ + pass + + def is_ipv6_misc(p): """ Is packet one of uninteresting IPv6 broadcasts? """ if p.haslayer(ICMPv6ND_RA): @@ -103,13 +108,15 @@ class VppPGInterface(VppInterface): """ Enable capture on this packet-generator interface""" try: if os.path.isfile(self.out_path): - os.rename(self.out_path, - "%s/history.[timestamp:%f].[%s-counter:%04d].%s" % - (self.test.tempdir, - time.time(), - self.name, - self.out_history_counter, - self._out_file)) + name = "%s/history.[timestamp:%f].[%s-counter:%04d].%s" % \ + (self.test.tempdir, + time.time(), + self.name, + self.out_history_counter, + self._out_file) + self.test.logger.debug("Renaming %s->%s" % + (self.out_path, name)) + os.rename(self.out_path, name) except: pass # FIXME this should be an API, but no such exists atm @@ -125,13 +132,15 @@ class VppPGInterface(VppInterface): """ try: if os.path.isfile(self.in_path): - os.rename(self.in_path, - "%s/history.[timestamp:%f].[%s-counter:%04d].%s" % - (self.test.tempdir, - time.time(), - self.name, - self.in_history_counter, - self._in_file)) + name = "%s/history.[timestamp:%f].[%s-counter:%04d].%s" %\ + (self.test.tempdir, + time.time(), + self.name, + self.in_history_counter, + self._in_file) + self.test.logger.debug("Renaming %s->%s" % + (self.in_path, name)) + os.rename(self.in_path, name) except: pass wrpcap(self.in_path, pkts) @@ -263,57 +272,50 @@ class VppPGInterface(VppInterface): :returns: True/False if the file is present or appears within timeout """ - limit = time.time() + timeout + deadline = time.time() + timeout if not os.path.isfile(self.out_path): self.test.logger.debug("Waiting for capture file %s to appear, " "timeout is %ss" % (self.out_path, timeout)) else: - self.test.logger.debug( - "Capture file %s already exists" % - self.out_path) + self.test.logger.debug("Capture file %s already exists" % + self.out_path) return True - while time.time() < limit: + while time.time() < deadline: if os.path.isfile(self.out_path): break time.sleep(0) # yield if os.path.isfile(self.out_path): self.test.logger.debug("Capture file appeared after %fs" % - (time.time() - (limit - timeout))) + (time.time() - (deadline - timeout))) else: self.test.logger.debug("Timeout - capture file still nowhere") return False return True - def wait_for_packet_data(self, deadline): + def verify_enough_packet_data_in_pcap(self): """ - Wait until enough data is available in the file handled by internal - pcap reader so that a whole packet can be read. + Check if enough data is available in file handled by internal pcap + reader so that a whole packet can be read. - :param deadline: timestamp by which the data must arrive - :raises Exception: if not enough data by deadline + :returns: True if enough data present, else False """ orig_pos = self._pcap_reader.f.tell() # save file position enough_data = False - while time.time() < deadline: - # read packet header from pcap - hdr = self._pcap_reader.f.read(16) - if len(hdr) < 16: - time.sleep(0) # yield - continue # cannot read full header, continue looping - # find the capture length - caplen + # read packet header from pcap + packet_header_size = 16 + caplen = None + end_pos = None + hdr = self._pcap_reader.f.read(packet_header_size) + if len(hdr) == packet_header_size: + # parse the capture length - caplen sec, usec, caplen, wirelen = struct.unpack( self._pcap_reader.endian + "IIII", hdr) self._pcap_reader.f.seek(0, 2) # seek to end of file end_pos = self._pcap_reader.f.tell() # get position at end if end_pos >= orig_pos + len(hdr) + caplen: enough_data = True # yay, we have enough data - break - self.test.logger.debug("Partial packet data in pcap") - time.sleep(0) # yield self._pcap_reader.f.seek(orig_pos, 0) # restore original position - if not enough_data: - raise Exception( - "Not enough data to read a full packet within deadline") + return enough_data def wait_for_packet(self, timeout, filter_out_fn=is_ipv6_misc): """ @@ -327,8 +329,8 @@ class VppPGInterface(VppInterface): deadline = time.time() + timeout if self._pcap_reader is None: if not self.wait_for_capture_file(timeout): - raise Exception("Capture file %s did not appear within " - "timeout" % self.out_path) + raise CaptureTimeoutError("Capture file %s did not appear " + "within timeout" % self.out_path) while time.time() < deadline: try: self._pcap_reader = PcapReader(self.out_path) @@ -338,12 +340,20 @@ class VppPGInterface(VppInterface): "Exception in scapy.PcapReader(%s): %s" % (self.out_path, format_exc())) if not self._pcap_reader: - raise Exception("Capture file %s did not appear within " - "timeout" % self.out_path) + raise CaptureTimeoutError("Capture file %s did not appear within " + "timeout" % self.out_path) - self.test.logger.debug("Waiting for packet") - while time.time() < deadline: - self.wait_for_packet_data(deadline) + poll = False + if timeout > 0: + self.test.logger.debug("Waiting for packet") + else: + poll = True + self.test.logger.debug("Polling for packet") + while time.time() < deadline or poll: + if not self.verify_enough_packet_data_in_pcap(): + time.sleep(0) # yield + poll = False + continue p = self._pcap_reader.recv() if p is not None: if filter_out_fn is not None and filter_out_fn(p): @@ -356,8 +366,9 @@ class VppPGInterface(VppInterface): (time.time() - (deadline - timeout))) return p time.sleep(0) # yield + poll = False self.test.logger.debug("Timeout - no packets received") - raise Exception("Packet didn't arrive within timeout") + raise CaptureTimeoutError("Packet didn't arrive within timeout") def create_arp_req(self): """Create ARP request applicable for this interface""" |