summaryrefslogtreecommitdiffstats
path: root/test/test_vxlan.py
blob: 028275ccedf9dcb7d14c7097c2666dea043ad38e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
#!/usr/bin/env python3

import socket
from util import ip4_range, reassemble4
import unittest
from framework import VppTestCase, VppTestRunner
from template_bd import BridgeDomain

from scapy.layers.l2 import Ether
from scapy.packet import Raw, bind_layers
from scapy.layers.inet import IP, UDP
from scapy.layers.vxlan import VXLAN

import util
from vpp_ip_route import VppIpRoute, VppRoutePath
from vpp_vxlan_tunnel import VppVxlanTunnel
from vpp_ip import INVALID_INDEX


class TestVxlan(BridgeDomain, VppTestCase):
    """ VXLAN Test Case """

    def __init__(self, *args):
        BridgeDomain.__init__(self)
        VppTestCase.__init__(self, *args)

    def encapsulate(self, pkt, vni):
        """
        Encapsulate the original payload frame by adding VXLAN header with its
        UDP, IP and Ethernet fields
        """
        return (Ether(src=self.pg0.remote_mac, dst=self.pg0.local_mac) /
                IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4) /
                UDP(sport=self.dport, dport=self.dport, chksum=0) /
                VXLAN(vni=vni, flags=self.flags) /
                pkt)

    def ip_range(self, start, end):
        """ range of remote ip's """
        return ip4_range(self.pg0.remote_ip4, start, end)

    def encap_mcast(self, pkt, src_ip, src_mac, vni):
        """
        Encapsulate the original payload frame by adding VXLAN header with its
        UDP, IP and Ethernet fields
        """
        return (Ether(src=src_mac, dst=self.mcast_mac) /
                IP(src=src_ip, dst=self.mcast_ip4) /
                UDP(sport=self.dport, dport=self.dport, chksum=0) /
                VXLAN(vni=vni, flags=self.flags) /
                pkt)

    def decapsulate(self, pkt):
        """
        Decapsulate the original payload frame by removing VXLAN header
        """
        # check if is set I flag
        self.assertEqual(pkt[VXLAN].flags, int('0x8', 16))
        return pkt[VXLAN].payload

    # Method for checking VXLAN encapsulation.
    #
    def check_encapsulation(self, pkt, vni, local_only=False, mcast_pkt=False):
        # TODO: add error messages
        # Verify source MAC is VPP_MAC and destination MAC is MY_MAC resolved
        #  by VPP using ARP.
        self.assertEqual(pkt[Ether].src, self.pg0.local_mac)
        if not local_only:
            if not mcast_pkt:
                self.assertEqual(pkt[Ether].dst, self.pg0.remote_mac)
            else:
                self.assertEqual(pkt[Ether].dst, type(self).mcast_mac)
        # Verify VXLAN tunnel source IP is VPP_IP and destination IP is MY_IP.
        self.assertEqual(pkt[IP].src, self.pg0.local_ip4)
        if not local_only:
            if not mcast_pkt:
                self.assertEqual(pkt[IP].dst, self.pg0.remote_ip4)
            else:
                self.assertEqual(pkt[IP].dst, type(self).mcast_ip4)
        # Verify UDP destination port is VXLAN 4789, source UDP port could be
        #  arbitrary.
        self.assertEqual(pkt[UDP].dport, self.dport)
        # Verify UDP checksum
        self.assert_udp_checksum_valid(pkt)
        # Verify VNI
        self.assertEqual(pkt[VXLAN].vni, vni)

    @classmethod
    def create_vxlan_flood_test_bd(cls, vni, n_ucast_tunnels, port):
        # Create 10 ucast vxlan tunnels under bd
        ip_range_start = 10
        ip_range_end = ip_range_start + n_ucast_tunnels
        next_hop_address = cls.pg0.remote_ip4
        for dest_ip4 in ip4_range(next_hop_address, ip_range_start,
                                  ip_range_end):
            # add host route so dest_ip4 will not be resolved
            rip = VppIpRoute(cls, dest_ip4, 32,
                             [VppRoutePath(next_hop_address,
                                           INVALID_INDEX)],
                             register=False)
            rip.add_vpp_config()

            r = VppVxlanTunnel(cls, src=cls.pg0.local_ip4,
                               src_port=port, dst_port=port,
                               dst=dest_ip4, vni=vni)
            r.add_vpp_config()
            cls.vapi.sw_interface_set_l2_bridge(r.sw_if_index, bd_id=vni)

    @classmethod
    def add_del_shared_mcast_dst_load(cls, port, is_add):
        """
        add or del tunnels sharing the same mcast dst
        to test vxlan ref_count mechanism
        """
        n_shared_dst_tunnels = 20
        vni_start = 10000
        vni_end = vni_start + n_shared_dst_tunnels
        for vni in range(vni_start, vni_end):
            r = VppVxlanTunnel(cls, src=cls.pg0.local_ip4,
                               src_port=port, dst_port=port,
                               dst=cls.mcast_ip4, mcast_sw_if_index=1, vni=vni)
            if is_add:
                r.add_vpp_config()
                if r.sw_if_index == 0xffffffff:
                    raise ValueError("bad sw_if_index: ~0")
            else:
                r.remove_vpp_config()

    @classmethod
    def add_shared_mcast_dst_load(cls, port):
        cls.add_del_shared_mcast_dst_load(port=port, is_add=1)

    @classmethod
    def del_shared_mcast_dst_load(cls, port):
        cls.add_del_shared_mcast_dst_load(port=port, is_add=0)

    @classmethod
    def add_del_mcast_tunnels_load(cls, port, is_add):
        """
        add or del tunnels to test vxlan stability
        """
        n_distinct_dst_tunnels = 200
        ip_range_start = 10
        ip_range_end = ip_range_start + n_distinct_dst_tunnels
        for dest_ip4 in ip4_range(cls.mcast_ip4, ip_range_start,
                                  ip_range_end):
            vni = bytearray(socket.inet_pton(socket.AF_INET, dest_ip4))[3]
            r = VppVxlanTunnel(cls, src=cls.pg0.local_ip4,
                               src_port=port, dst_port=port,
                               dst=dest_ip4, mcast_sw_if_index=1, vni=vni)
            if is_add:
                r.add_vpp_config()
            else:
                r.remove_vpp_config()

    @classmethod
    def add_mcast_tunnels_load(cls, port):
        cls.add_del_mcast_tunnels_load(port=port, is_add=1)

    @classmethod
    def del_mcast_tunnels_load(cls, port):
        cls.add_del_mcast_tunnels_load(port=port, is_add=0)

    # Class method to start the VXLAN test case.
    #  Overrides setUpClass method in VppTestCase class.
    #  Python try..except statement is used to ensure that the tear down of
    #  the class will be executed even if exception is raised.
    #  @param cls The class pointer.
    @classmethod
    def setUpClass(cls):
        super(TestVxlan, cls).setUpClass()

        try:
            cls.flags = 0x8

            # Create 2 pg interfaces.
            cls.create_pg_interfaces(range(4))
            for pg in cls.pg_interfaces:
                pg.admin_up()

            # Configure IPv4 addresses on VPP pg0.
            cls.pg0.config_ip4()

            # Resolve MAC address for VPP's IP address on pg0.
            cls.pg0.resolve_arp()

            # Our Multicast address
            cls.mcast_ip4 = '239.1.1.1'
            cls.mcast_mac = util.mcast_ip_to_mac(cls.mcast_ip4)
        except Exception:
            cls.tearDownClass()
            raise

    @classmethod
    def tearDownClass(cls):
        super(TestVxlan, cls).tearDownClass()

    def setUp(self):
        super(TestVxlan, self).setUp()

    def createVxLANInterfaces(self, port=4789):
        # Create VXLAN VTEP on VPP pg0, and put vxlan_tunnel0 and pg1
        #  into BD.
        self.dport = port

        self.single_tunnel_vni = 0x12345
        self.single_tunnel_bd = 1
        r = VppVxlanTunnel(self, src=self.pg0.local_ip4,
                           dst=self.pg0.remote_ip4,
                           src_port=self.dport, dst_port=self.dport,
                           vni=self.single_tunnel_vni)
        r.add_vpp_config()
        self.vapi.sw_interface_set_l2_bridge(rx_sw_if_index=r.sw_if_index,
                                             bd_id=self.single_tunnel_bd)
        self.vapi.sw_interface_set_l2_bridge(
            rx_sw_if_index=self.pg1.sw_if_index, bd_id=self.single_tunnel_bd)

        # Setup vni 2 to test multicast flooding
        self.n_ucast_tunnels = 10
        self.mcast_flood_bd = 2
        self.create_vxlan_flood_test_bd(self.mcast_flood_bd,
                                        self.n_ucast_tunnels,
                                        self.dport)
        r = VppVxlanTunnel(self, src=self.pg0.local_ip4, dst=self.mcast_ip4,
                           src_port=self.dport, dst_port=self.dport,
                           mcast_sw_if_index=1, vni=self.mcast_flood_bd)
        r.add_vpp_config()
        self.vapi.sw_interface_set_l2_bridge(rx_sw_if_index=r.sw_if_index,
                                             bd_id=self.mcast_flood_bd)
        self.vapi.sw_interface_set_l2_bridge(
            rx_sw_if_index=self.pg2.sw_if_index, bd_id=self.mcast_flood_bd)

        # Add and delete mcast tunnels to check stability
        self.add_shared_mcast_dst_load(self.dport)
        self.add_mcast_tunnels_load(self.dport)
        self.del_shared_mcast_dst_load(self.dport)
        self.del_mcast_tunnels_load(self.dport)

        # Setup vni 3 to test unicast flooding
        self.ucast_flood_bd = 3
        self.create_vxlan_flood_test_bd(self.ucast_flood_bd,
                                        self.n_ucast_tunnels,
                                        self.dport)
        self.vapi.sw_interface_set_l2_bridge(
            rx_sw_if_index=self.pg3.sw_if_index, bd_id=self.ucast_flood_bd)

        # Set scapy listen custom port for VxLAN
        bind_layers(UDP, VXLAN, dport=self.dport)

    def encap_big_packet(self):
        self.vapi.sw_interface_set_mtu(self.pg0.sw_if_index, [1500, 0, 0, 0])

        frame = (Ether(src='00:00:00:00:00:02', dst='00:00:00:00:00:01') /
                 IP(src='4.3.2.1', dst='1.2.3.4') /
                 UDP(sport=20000, dport=10000) /
                 Raw(b'\xa5' * 1450))

        self.pg1.add_stream([frame])

        self.pg0.enable_capture()

        self.pg_start()

        # Pick first received frame and check if it's correctly encapsulated.
        out = self.pg0.get_capture(2)
        ether = out[0]
        pkt = reassemble4(out)
        pkt = ether / pkt
        self.check_encapsulation(pkt, self.single_tunnel_vni)

        payload = self.decapsulate(pkt)
        # TODO: Scapy bug?
        # self.assert_eq_pkts(payload, frame)

    """
    Tests with default port (4789)
    """
    def test_decap(self):
        """ Decapsulation test
        from BridgeDoman
        """
        self.createVxLANInterfaces()
        super(TestVxlan, self).test_decap()

    def test_encap(self):
        """ Encapsulation test
        from BridgeDoman
        """
        self.createVxLANInterfaces()
        super(TestVxlan, self).test_encap()

    def test_encap_big_packet(self):
        """ Encapsulation test send big frame from pg1
        Verify receipt of encapsulated frames on pg0
        """
        self.createVxLANInterfaces()
        self.encap_big_packet()

    def test_ucast_flood(self):
        """ Unicast flood test
        from BridgeDoman
        """
        self.createVxLANInterfaces()
        super(TestVxlan, self).test_ucast_flood()

    def test_mcast_flood(self):
        """ Multicast flood test
        from BridgeDoman
        """
        self.createVxLANInterfaces()
        super(TestVxlan, self).test_mcast_flood()

    def test_mcast_rcv(self):
        """ Multicast receive test
        from BridgeDoman
        """
        self.createVxLANInterfaces()
        super(TestVxlan, self).test_mcast_rcv()

    """
    Tests with custom port
    """
    def test_decap_custom_port(self):
        """ Decapsulation test custom port
        from BridgeDoman
        """
        self.createVxLANInterfaces(1111)
        super(TestVxlan, self).test_decap()

    def test_encap_custom_port(self):
        """ Encapsulation test custom port
        from BridgeDoman
        """
        self.createVxLANInterfaces(1111)
        super(TestVxlan, self).test_encap()

    def test_ucast_flood_custom_port(self):
        """ Unicast flood test custom port
        from BridgeDoman
        """
        self.createVxLANInterfaces(1111)
        super(TestVxlan, self).test_ucast_flood()

    def test_mcast_flood_custom_port(self):
        """ Multicast flood test custom port
        from BridgeDoman
        """
        self.createVxLANInterfaces(1111)
        super(TestVxlan, self).test_mcast_flood()

    def test_mcast_rcv_custom_port(self):
        """ Multicast receive test custom port
        from BridgeDoman
        """
        self.createVxLANInterfaces(1111)
        super(TestVxlan, self).test_mcast_rcv()

    # Method to define VPP actions before tear down of the test case.
    #  Overrides tearDown method in VppTestCase class.
    #  @param self The object pointer.

    def tearDown(self):
        super(TestVxlan, self).tearDown()

    def show_commands_at_teardown(self):
        self.logger.info(self.vapi.cli("show bridge-domain 1 detail"))
        self.logger.info(self.vapi.cli("show bridge-domain 2 detail"))
        self.logger.info(self.vapi.cli("show bridge-domain 3 detail"))
        self.logger.info(self.vapi.cli("show vxlan tunnel"))


class TestVxlan2(VppTestCase):
    """ VXLAN Test Case """
    def setUp(self):
        super(TestVxlan2, self).setUp()

        # Create 2 pg interfaces.
        self.create_pg_interfaces(range(4))
        for pg in self.pg_interfaces:
            pg.admin_up()

        # Configure IPv4 addresses on VPP pg0.
        self.pg0.config_ip4()
        self.pg0.resolve_arp()

    def tearDown(self):
        super(TestVxlan2, self).tearDown()

    def test_xconnect(self):
        """ VXLAN source address not local """

        #
        # test the broken configuration of a VXLAN tunnel whose
        # source address is not local ot the box. packets sent
        # through the tunnel should be dropped
        #
        t = VppVxlanTunnel(self,
                           src="10.0.0.5",
                           dst=self.pg0.local_ip4,
                           vni=1000)
        t.add_vpp_config()
        t.admin_up()

        self.vapi.sw_interface_set_l2_xconnect(t.sw_if_index,
                                               self.pg1.sw_if_index,
                                               enable=1)
        self.vapi.sw_interface_set_l2_xconnect(self.pg1.sw_if_index,
                                               t.sw_if_index,
                                               enable=1)

        p = (Ether(src="00:11:22:33:44:55",
                   dst="00:00:00:11:22:33") /
             IP(src="4.3.2.1", dst="1.2.3.4") /
             UDP(sport=20000, dport=10000) /
             Raw(b'\xa5' * 1450))

        rx = self.send_and_assert_no_replies(self.pg1, [p])


if __name__ == '__main__':
    unittest.main(testRunner=VppTestRunner)
'#n2402'>2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367
/*
 * Copyright (c) 2017-2019 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this
 * 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.
 */

#include <stdio.h>
#include <stdlib.h>
#include <vcl/vppcom.h>
#include <vcl/vcl_debug.h>
#include <vcl/vcl_private.h>
#include <svm/fifo_segment.h>

__thread uword __vcl_worker_index = ~0;

static int
vcl_wait_for_segment (u64 segment_handle)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  u32 wait_for_seconds = 10, segment_index;
  f64 timeout;

  if (segment_handle == VCL_INVALID_SEGMENT_HANDLE)
    return 0;

  timeout = clib_time_now (&wrk->clib_time) + wait_for_seconds;
  while (clib_time_now (&wrk->clib_time) < timeout)
    {
      segment_index = vcl_segment_table_lookup (segment_handle);
      if (segment_index != VCL_INVALID_SEGMENT_INDEX)
	return 0;
      usleep (10);
    }
  return 1;
}

static inline int
vcl_mq_dequeue_batch (vcl_worker_t * wrk, svm_msg_q_t * mq, u32 n_max_msg)
{
  svm_msg_q_msg_t *msg;
  u32 n_msgs;
  int i;

  n_msgs = clib_min (svm_msg_q_size (mq), n_max_msg);
  for (i = 0; i < n_msgs; i++)
    {
      vec_add2 (wrk->mq_msg_vector, msg, 1);
      svm_msg_q_sub_w_lock (mq, msg);
    }
  return n_msgs;
}

const char *
vppcom_session_state_str (vcl_session_state_t state)
{
  char *st;

  switch (state)
    {
    case STATE_START:
      st = "STATE_START";
      break;

    case STATE_CONNECT:
      st = "STATE_CONNECT";
      break;

    case STATE_LISTEN:
      st = "STATE_LISTEN";
      break;

    case STATE_ACCEPT:
      st = "STATE_ACCEPT";
      break;

    case STATE_VPP_CLOSING:
      st = "STATE_VPP_CLOSING";
      break;

    case STATE_DISCONNECT:
      st = "STATE_DISCONNECT";
      break;

    case STATE_FAILED:
      st = "STATE_FAILED";
      break;

    case STATE_UPDATED:
      st = "STATE_UPDATED";
      break;

    case STATE_LISTEN_NO_MQ:
      st = "STATE_LISTEN_NO_MQ";
      break;

    default:
      st = "UNKNOWN_STATE";
      break;
    }

  return st;
}

u8 *
format_ip4_address (u8 * s, va_list * args)
{
  u8 *a = va_arg (*args, u8 *);
  return format (s, "%d.%d.%d.%d", a[0], a[1], a[2], a[3]);
}

u8 *
format_ip6_address (u8 * s, va_list * args)
{
  ip6_address_t *a = va_arg (*args, ip6_address_t *);
  u32 i, i_max_n_zero, max_n_zeros, i_first_zero, n_zeros, last_double_colon;

  i_max_n_zero = ARRAY_LEN (a->as_u16);
  max_n_zeros = 0;
  i_first_zero = i_max_n_zero;
  n_zeros = 0;
  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
    {
      u32 is_zero = a->as_u16[i] == 0;
      if (is_zero && i_first_zero >= ARRAY_LEN (a->as_u16))
	{
	  i_first_zero = i;
	  n_zeros = 0;
	}
      n_zeros += is_zero;
      if ((!is_zero && n_zeros > max_n_zeros)
	  || (i + 1 >= ARRAY_LEN (a->as_u16) && n_zeros > max_n_zeros))
	{
	  i_max_n_zero = i_first_zero;
	  max_n_zeros = n_zeros;
	  i_first_zero = ARRAY_LEN (a->as_u16);
	  n_zeros = 0;
	}
    }

  last_double_colon = 0;
  for (i = 0; i < ARRAY_LEN (a->as_u16); i++)
    {
      if (i == i_max_n_zero && max_n_zeros > 1)
	{
	  s = format (s, "::");
	  i += max_n_zeros - 1;
	  last_double_colon = 1;
	}
      else
	{
	  s = format (s, "%s%x",
		      (last_double_colon || i == 0) ? "" : ":",
		      clib_net_to_host_u16 (a->as_u16[i]));
	  last_double_colon = 0;
	}
    }

  return s;
}

/* Format an IP46 address. */
u8 *
format_ip46_address (u8 * s, va_list * args)
{
  ip46_address_t *ip46 = va_arg (*args, ip46_address_t *);
  ip46_type_t type = va_arg (*args, ip46_type_t);
  int is_ip4 = 1;

  switch (type)
    {
    case IP46_TYPE_ANY:
      is_ip4 = ip46_address_is_ip4 (ip46);
      break;
    case IP46_TYPE_IP4:
      is_ip4 = 1;
      break;
    case IP46_TYPE_IP6:
      is_ip4 = 0;
      break;
    }

  return is_ip4 ?
    format (s, "%U", format_ip4_address, &ip46->ip4) :
    format (s, "%U", format_ip6_address, &ip46->ip6);
}

/*
 * VPPCOM Utility Functions
 */


static void
vcl_send_session_accepted_reply (svm_msg_q_t * mq, u32 context,
				 session_handle_t handle, int retval)
{
  app_session_evt_t _app_evt, *app_evt = &_app_evt;
  session_accepted_reply_msg_t *rmp;
  app_alloc_ctrl_evt_to_vpp (mq, app_evt, SESSION_CTRL_EVT_ACCEPTED_REPLY);
  rmp = (session_accepted_reply_msg_t *) app_evt->evt->data;
  rmp->handle = handle;
  rmp->context = context;
  rmp->retval = retval;
  app_send_ctrl_evt_to_vpp (mq, app_evt);
}

static void
vcl_send_session_disconnected_reply (svm_msg_q_t * mq, u32 context,
				     session_handle_t handle, int retval)
{
  app_session_evt_t _app_evt, *app_evt = &_app_evt;
  session_disconnected_reply_msg_t *rmp;
  app_alloc_ctrl_evt_to_vpp (mq, app_evt,
			     SESSION_CTRL_EVT_DISCONNECTED_REPLY);
  rmp = (session_disconnected_reply_msg_t *) app_evt->evt->data;
  rmp->handle = handle;
  rmp->context = context;
  rmp->retval = retval;
  app_send_ctrl_evt_to_vpp (mq, app_evt);
}

static void
vcl_send_session_reset_reply (svm_msg_q_t * mq, u32 context,
			      session_handle_t handle, int retval)
{
  app_session_evt_t _app_evt, *app_evt = &_app_evt;
  session_reset_reply_msg_t *rmp;
  app_alloc_ctrl_evt_to_vpp (mq, app_evt, SESSION_CTRL_EVT_RESET_REPLY);
  rmp = (session_reset_reply_msg_t *) app_evt->evt->data;
  rmp->handle = handle;
  rmp->context = context;
  rmp->retval = retval;
  app_send_ctrl_evt_to_vpp (mq, app_evt);
}

void
vcl_send_session_worker_update (vcl_worker_t * wrk, vcl_session_t * s,
				u32 wrk_index)
{
  app_session_evt_t _app_evt, *app_evt = &_app_evt;
  session_worker_update_msg_t *mp;
  svm_msg_q_t *mq;

  mq = vcl_session_vpp_evt_q (wrk, s);
  app_alloc_ctrl_evt_to_vpp (mq, app_evt, SESSION_CTRL_EVT_WORKER_UPDATE);
  mp = (session_worker_update_msg_t *) app_evt->evt->data;
  mp->client_index = wrk->my_client_index;
  mp->handle = s->vpp_handle;
  mp->req_wrk_index = wrk->vpp_wrk_index;
  mp->wrk_index = wrk_index;
  app_send_ctrl_evt_to_vpp (mq, app_evt);
}

static u32
vcl_session_accepted_handler (vcl_worker_t * wrk, session_accepted_msg_t * mp,
			      u32 ls_index)
{
  vcl_session_t *session, *listen_session;
  svm_fifo_t *rx_fifo, *tx_fifo;
  u32 vpp_wrk_index;
  svm_msg_q_t *evt_q;

  session = vcl_session_alloc (wrk);

  listen_session = vcl_session_get (wrk, ls_index);
  if (listen_session->vpp_handle != mp->listener_handle)
    {
      VDBG (0, "ERROR: listener handle %lu does not match session %u",
	    mp->listener_handle, ls_index);
      goto error;
    }

  if (vcl_wait_for_segment (mp->segment_handle))
    {
      VDBG (0, "ERROR: segment for session %u couldn't be mounted!",
	    session->session_index);
      goto error;
    }

  rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
  tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
  session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
					 svm_msg_q_t *);
  rx_fifo->client_session_index = session->session_index;
  tx_fifo->client_session_index = session->session_index;
  rx_fifo->client_thread_index = vcl_get_worker_index ();
  tx_fifo->client_thread_index = vcl_get_worker_index ();
  vpp_wrk_index = tx_fifo->master_thread_index;
  vec_validate (wrk->vpp_event_queues, vpp_wrk_index);
  wrk->vpp_event_queues[vpp_wrk_index] = session->vpp_evt_q;

  session->vpp_handle = mp->handle;
  session->vpp_thread_index = rx_fifo->master_thread_index;
  session->rx_fifo = rx_fifo;
  session->tx_fifo = tx_fifo;

  session->session_state = STATE_ACCEPT;
  session->transport.rmt_port = mp->rmt.port;
  session->transport.is_ip4 = mp->rmt.is_ip4;
  clib_memcpy_fast (&session->transport.rmt_ip, &mp->rmt.ip,
		    sizeof (ip46_address_t));

  vcl_session_table_add_vpp_handle (wrk, mp->handle, session->session_index);
  session->transport.lcl_port = listen_session->transport.lcl_port;
  session->transport.lcl_ip = listen_session->transport.lcl_ip;
  session->session_type = listen_session->session_type;
  session->is_dgram = session->session_type == VPPCOM_PROTO_UDP;

  VDBG (1, "session %u [0x%llx]: client accept request from %s address %U"
	" port %d queue %p!", session->session_index, mp->handle,
	mp->rmt.is_ip4 ? "IPv4" : "IPv6", format_ip46_address, &mp->rmt.ip,
	mp->rmt.is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
	clib_net_to_host_u16 (mp->rmt.port), session->vpp_evt_q);
  vcl_evt (VCL_EVT_ACCEPT, session, listen_session, session_index);

  vcl_send_session_accepted_reply (session->vpp_evt_q, mp->context,
				   session->vpp_handle, 0);

  return session->session_index;

error:
  evt_q = uword_to_pointer (mp->vpp_event_queue_address, svm_msg_q_t *);
  vcl_send_session_accepted_reply (evt_q, mp->context, mp->handle,
				   VNET_API_ERROR_INVALID_ARGUMENT);
  vcl_session_free (wrk, session);
  return VCL_INVALID_SESSION_INDEX;
}

static u32
vcl_session_connected_handler (vcl_worker_t * wrk,
			       session_connected_msg_t * mp)
{
  u32 session_index, vpp_wrk_index;
  svm_fifo_t *rx_fifo, *tx_fifo;
  vcl_session_t *session = 0;

  session_index = mp->context;
  session = vcl_session_get (wrk, session_index);
  if (!session)
    {
      VDBG (0, "ERROR: vpp handle 0x%llx has no session index (%u)!",
	    mp->handle, session_index);
      return VCL_INVALID_SESSION_INDEX;
    }
  if (mp->retval)
    {
      VDBG (0, "ERROR: session index %u: connect failed! %U",
	    session_index, format_api_error, ntohl (mp->retval));
      session->session_state = STATE_FAILED;
      session->vpp_handle = mp->handle;
      return session_index;
    }

  rx_fifo = uword_to_pointer (mp->server_rx_fifo, svm_fifo_t *);
  tx_fifo = uword_to_pointer (mp->server_tx_fifo, svm_fifo_t *);
  if (vcl_wait_for_segment (mp->segment_handle))
    {
      VDBG (0, "segment for session %u couldn't be mounted!",
	    session->session_index);
      session->session_state = STATE_FAILED;
      return VCL_INVALID_SESSION_INDEX;
    }

  rx_fifo->client_session_index = session_index;
  tx_fifo->client_session_index = session_index;
  rx_fifo->client_thread_index = vcl_get_worker_index ();
  tx_fifo->client_thread_index = vcl_get_worker_index ();

  session->vpp_evt_q = uword_to_pointer (mp->vpp_event_queue_address,
					 svm_msg_q_t *);
  vpp_wrk_index = tx_fifo->master_thread_index;
  vec_validate (wrk->vpp_event_queues, vpp_wrk_index);
  wrk->vpp_event_queues[vpp_wrk_index] = session->vpp_evt_q;

  if (mp->ct_rx_fifo)
    {
      session->ct_rx_fifo = uword_to_pointer (mp->ct_rx_fifo, svm_fifo_t *);
      session->ct_tx_fifo = uword_to_pointer (mp->ct_tx_fifo, svm_fifo_t *);
      if (vcl_wait_for_segment (mp->ct_segment_handle))
	{
	  VDBG (0, "ct segment for session %u couldn't be mounted!",
		session->session_index);
	  session->session_state = STATE_FAILED;
	  return VCL_INVALID_SESSION_INDEX;
	}
    }

  session->rx_fifo = rx_fifo;
  session->tx_fifo = tx_fifo;
  session->vpp_handle = mp->handle;
  session->vpp_thread_index = rx_fifo->master_thread_index;
  session->transport.is_ip4 = mp->lcl.is_ip4;
  clib_memcpy_fast (&session->transport.lcl_ip, &mp->lcl.ip,
		    sizeof (session->transport.lcl_ip));
  session->transport.lcl_port = mp->lcl.port;
  session->session_state = STATE_CONNECT;

  /* Add it to lookup table */
  vcl_session_table_add_vpp_handle (wrk, mp->handle, session_index);

  VDBG (1, "session %u [0x%llx] connected! rx_fifo %p, refcnt %d, tx_fifo %p,"
	" refcnt %d", session_index, mp->handle, session->rx_fifo,
	session->rx_fifo->refcnt, session->tx_fifo, session->tx_fifo->refcnt);

  return session_index;
}

static int
vcl_flag_accepted_session (vcl_session_t * session, u64 handle, u32 flags)
{
  vcl_session_msg_t *accepted_msg;
  int i;

  for (i = 0; i < vec_len (session->accept_evts_fifo); i++)
    {
      accepted_msg = &session->accept_evts_fifo[i];
      if (accepted_msg->accepted_msg.handle == handle)
	{
	  accepted_msg->flags |= flags;
	  return 1;
	}
    }
  return 0;
}

static u32
vcl_session_reset_handler (vcl_worker_t * wrk,
			   session_reset_msg_t * reset_msg)
{
  vcl_session_t *session;
  u32 sid;

  sid = vcl_session_index_from_vpp_handle (wrk, reset_msg->handle);
  session = vcl_session_get (wrk, sid);
  if (!session)
    {
      VDBG (0, "request to reset unknown handle 0x%llx", reset_msg->handle);
      return VCL_INVALID_SESSION_INDEX;
    }

  /* Caught a reset before actually accepting the session */
  if (session->session_state == STATE_LISTEN)
    {

      if (!vcl_flag_accepted_session (session, reset_msg->handle,
				      VCL_ACCEPTED_F_RESET))
	VDBG (0, "session was not accepted!");
      return VCL_INVALID_SESSION_INDEX;
    }

  session->session_state = STATE_DISCONNECT;
  VDBG (0, "reset session %u [0x%llx]", sid, reset_msg->handle);
  return sid;
}

static u32
vcl_session_bound_handler (vcl_worker_t * wrk, session_bound_msg_t * mp)
{
  vcl_session_t *session;
  u32 sid = mp->context;

  session = vcl_session_get (wrk, sid);
  if (mp->retval)
    {
      VERR ("session %u [0x%llx]: bind failed: %U", sid, mp->handle,
	    format_api_error, mp->retval);
      if (session)
	{
	  session->session_state = STATE_FAILED;
	  session->vpp_handle = mp->handle;
	  return sid;
	}
      else
	{
	  VDBG (0, "ERROR: session %u [0x%llx]: Invalid session index!",
		sid, mp->handle);
	  return VCL_INVALID_SESSION_INDEX;
	}
    }

  session->vpp_handle = mp->handle;
  session->transport.is_ip4 = mp->lcl_is_ip4;
  clib_memcpy_fast (&session->transport.lcl_ip, mp->lcl_ip,
		    sizeof (ip46_address_t));
  session->transport.lcl_port = mp->lcl_port;
  vcl_session_table_add_listener (wrk, mp->handle, sid);
  session->session_state = STATE_LISTEN;

  session->vpp_evt_q = uword_to_pointer (mp->vpp_evt_q, svm_msg_q_t *);
  vec_validate (wrk->vpp_event_queues, 0);
  wrk->vpp_event_queues[0] = session->vpp_evt_q;

  if (session->is_dgram)
    {
      svm_fifo_t *rx_fifo, *tx_fifo;
      session->vpp_evt_q = uword_to_pointer (mp->vpp_evt_q, svm_msg_q_t *);
      rx_fifo = uword_to_pointer (mp->rx_fifo, svm_fifo_t *);
      rx_fifo->client_session_index = sid;
      tx_fifo = uword_to_pointer (mp->tx_fifo, svm_fifo_t *);
      tx_fifo->client_session_index = sid;
      session->rx_fifo = rx_fifo;
      session->tx_fifo = tx_fifo;
    }

  VDBG (0, "session %u [0x%llx]: listen succeeded!", sid, mp->handle);
  return sid;
}

static void
vcl_session_unlisten_reply_handler (vcl_worker_t * wrk, void *data)
{
  session_unlisten_reply_msg_t *mp = (session_unlisten_reply_msg_t *) data;
  vcl_session_t *s;

  s = vcl_session_get_w_vpp_handle (wrk, mp->handle);
  if (!s || s->session_state != STATE_DISCONNECT)
    {
      VDBG (0, "Unlisten reply with wrong handle %llx", mp->handle);
      return;
    }

  if (mp->retval)
    VDBG (0, "ERROR: session %u [0xllx]: unlisten failed: %U",
	  s->session_index, mp->handle, format_api_error, ntohl (mp->retval));

  if (mp->context != wrk->wrk_index)
    VDBG (0, "wrong context");

  vcl_session_table_del_vpp_handle (wrk, mp->handle);
  vcl_session_free (wrk, s);
}

static vcl_session_t *
vcl_session_accepted (vcl_worker_t * wrk, session_accepted_msg_t * msg)
{
  vcl_session_msg_t *vcl_msg;
  vcl_session_t *session;

  session = vcl_session_get_w_vpp_handle (wrk, msg->handle);
  if (PREDICT_FALSE (session != 0))
    VWRN ("session overlap handle %lu state %u!", msg->handle,
	  session->session_state);

  session = vcl_session_table_lookup_listener (wrk, msg->listener_handle);
  if (!session)
    {
      VERR ("couldn't find listen session: listener handle %llx",
	    msg->listener_handle);
      return 0;
    }

  clib_fifo_add2 (session->accept_evts_fifo, vcl_msg);
  vcl_msg->accepted_msg = *msg;
  /* Session handle points to listener until fully accepted by app */
  vcl_session_table_add_vpp_handle (wrk, msg->handle, session->session_index);

  return session;
}

static vcl_session_t *
vcl_session_disconnected_handler (vcl_worker_t * wrk,
				  session_disconnected_msg_t * msg)
{
  vcl_session_t *session;

  session = vcl_session_get_w_vpp_handle (wrk, msg->handle);
  if (!session)
    {
      VDBG (0, "request to disconnect unknown handle 0x%llx", msg->handle);
      return 0;
    }

  /* Caught a disconnect before actually accepting the session */
  if (session->session_state == STATE_LISTEN)
    {
      if (!vcl_flag_accepted_session (session, msg->handle,
				      VCL_ACCEPTED_F_CLOSED))
	VDBG (0, "session was not accepted!");
      return 0;
    }

  session->session_state = STATE_VPP_CLOSING;
  return session;
}

static void
vcl_session_req_worker_update_handler (vcl_worker_t * wrk, void *data)
{
  session_req_worker_update_msg_t *msg;
  vcl_session_t *s;

  msg = (session_req_worker_update_msg_t *) data;
  s = vcl_session_get_w_vpp_handle (wrk, msg->session_handle);
  if (!s)
    return;

  vec_add1 (wrk->pending_session_wrk_updates, s->session_index);
}

static void
vcl_session_worker_update_reply_handler (vcl_worker_t * wrk, void *data)
{
  session_worker_update_reply_msg_t *msg;
  vcl_session_t *s;

  msg = (session_worker_update_reply_msg_t *) data;
  s = vcl_session_get_w_vpp_handle (wrk, msg->handle);
  if (!s)
    {
      VDBG (0, "unknown handle 0x%llx", msg->handle);
      return;
    }
  if (vcl_wait_for_segment (msg->segment_handle))
    {
      clib_warning ("segment for session %u couldn't be mounted!",
		    s->session_index);
      return;
    }

  if (s->rx_fifo)
    {
      s->rx_fifo = uword_to_pointer (msg->rx_fifo, svm_fifo_t *);
      s->tx_fifo = uword_to_pointer (msg->tx_fifo, svm_fifo_t *);
      s->rx_fifo->client_session_index = s->session_index;
      s->tx_fifo->client_session_index = s->session_index;
      s->rx_fifo->client_thread_index = wrk->wrk_index;
      s->tx_fifo->client_thread_index = wrk->wrk_index;
    }
  s->session_state = STATE_UPDATED;

  VDBG (0, "session %u[0x%llx] moved to worker %u", s->session_index,
	s->vpp_handle, wrk->wrk_index);
}

static int
vcl_handle_mq_event (vcl_worker_t * wrk, session_event_t * e)
{
  session_disconnected_msg_t *disconnected_msg;
  vcl_session_t *session;

  switch (e->event_type)
    {
    case SESSION_IO_EVT_RX:
    case SESSION_IO_EVT_TX:
      session = vcl_session_get (wrk, e->session_index);
      if (!session || !(session->session_state & STATE_OPEN))
	break;
      vec_add1 (wrk->unhandled_evts_vector, *e);
      break;
    case SESSION_CTRL_EVT_ACCEPTED:
      vcl_session_accepted (wrk, (session_accepted_msg_t *) e->data);
      break;
    case SESSION_CTRL_EVT_CONNECTED:
      vcl_session_connected_handler (wrk,
				     (session_connected_msg_t *) e->data);
      break;
    case SESSION_CTRL_EVT_DISCONNECTED:
      disconnected_msg = (session_disconnected_msg_t *) e->data;
      session = vcl_session_disconnected_handler (wrk, disconnected_msg);
      if (!session)
	break;
      VDBG (0, "disconnected session %u [0x%llx]", session->session_index,
	    session->vpp_handle);
      break;
    case SESSION_CTRL_EVT_RESET:
      vcl_session_reset_handler (wrk, (session_reset_msg_t *) e->data);
      break;
    case SESSION_CTRL_EVT_BOUND:
      vcl_session_bound_handler (wrk, (session_bound_msg_t *) e->data);
      break;
    case SESSION_CTRL_EVT_UNLISTEN_REPLY:
      vcl_session_unlisten_reply_handler (wrk, e->data);
      break;
    case SESSION_CTRL_EVT_REQ_WORKER_UPDATE:
      vcl_session_req_worker_update_handler (wrk, e->data);
      break;
    case SESSION_CTRL_EVT_WORKER_UPDATE_REPLY:
      vcl_session_worker_update_reply_handler (wrk, e->data);
      break;
    default:
      clib_warning ("unhandled %u", e->event_type);
    }
  return VPPCOM_OK;
}

static int
vppcom_wait_for_session_state_change (u32 session_index,
				      vcl_session_state_t state,
				      f64 wait_for_time)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  f64 timeout = clib_time_now (&wrk->clib_time) + wait_for_time;
  vcl_session_t *volatile session;
  svm_msg_q_msg_t msg;
  session_event_t *e;

  do
    {
      session = vcl_session_get (wrk, session_index);
      if (PREDICT_FALSE (!session))
	{
	  return VPPCOM_EBADFD;
	}
      if (session->session_state & state)
	{
	  return VPPCOM_OK;
	}
      if (session->session_state & STATE_FAILED)
	{
	  return VPPCOM_ECONNREFUSED;
	}

      if (svm_msg_q_sub (wrk->app_event_queue, &msg, SVM_Q_NOWAIT, 0))
	{
	  usleep (100);
	  continue;
	}
      e = svm_msg_q_msg_data (wrk->app_event_queue, &msg);
      vcl_handle_mq_event (wrk, e);
      svm_msg_q_free_msg (wrk->app_event_queue, &msg);
    }
  while (clib_time_now (&wrk->clib_time) < timeout);

  VDBG (0, "timeout waiting for state 0x%x (%s)", state,
	vppcom_session_state_str (state));
  vcl_evt (VCL_EVT_SESSION_TIMEOUT, session, session_state);

  return VPPCOM_ETIMEDOUT;
}

static void
vcl_handle_pending_wrk_updates (vcl_worker_t * wrk)
{
  vcl_session_state_t state;
  vcl_session_t *s;
  u32 *sip;

  if (PREDICT_TRUE (vec_len (wrk->pending_session_wrk_updates) == 0))
    return;

  vec_foreach (sip, wrk->pending_session_wrk_updates)
  {
    s = vcl_session_get (wrk, *sip);
    vcl_send_session_worker_update (wrk, s, wrk->wrk_index);
    state = s->session_state;
    vppcom_wait_for_session_state_change (s->session_index, STATE_UPDATED, 5);
    s->session_state = state;
  }
  vec_reset_length (wrk->pending_session_wrk_updates);
}

void
vcl_flush_mq_events (void)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  svm_msg_q_msg_t *msg;
  session_event_t *e;
  svm_msg_q_t *mq;
  int i;

  mq = wrk->app_event_queue;
  svm_msg_q_lock (mq);
  vcl_mq_dequeue_batch (wrk, mq, ~0);
  svm_msg_q_unlock (mq);

  for (i = 0; i < vec_len (wrk->mq_msg_vector); i++)
    {
      msg = vec_elt_at_index (wrk->mq_msg_vector, i);
      e = svm_msg_q_msg_data (mq, msg);
      vcl_handle_mq_event (wrk, e);
      svm_msg_q_free_msg (mq, msg);
    }
  vec_reset_length (wrk->mq_msg_vector);
  vcl_handle_pending_wrk_updates (wrk);
}

static int
vppcom_app_session_enable (void)
{
  int rv;

  if (vcm->app_state != STATE_APP_ENABLED)
    {
      vppcom_send_session_enable_disable (1 /* is_enabled == TRUE */ );
      rv = vcl_wait_for_app_state_change (STATE_APP_ENABLED);
      if (PREDICT_FALSE (rv))
	{
	  VDBG (0, "application session enable timed out! returning %d (%s)",
		rv, vppcom_retval_str (rv));
	  return rv;
	}
    }
  return VPPCOM_OK;
}

static int
vppcom_app_attach (void)
{
  int rv;

  vppcom_app_send_attach ();
  rv = vcl_wait_for_app_state_change (STATE_APP_ATTACHED);
  if (PREDICT_FALSE (rv))
    {
      VDBG (0, "application attach timed out! returning %d (%s)", rv,
	    vppcom_retval_str (rv));
      return rv;
    }

  return VPPCOM_OK;
}

static int
vppcom_session_unbind (u32 session_handle)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *session = 0;
  u64 vpp_handle;

  session = vcl_session_get_w_handle (wrk, session_handle);
  if (!session)
    return VPPCOM_EBADFD;

  vpp_handle = session->vpp_handle;
  session->vpp_handle = ~0;
  session->session_state = STATE_DISCONNECT;

  VDBG (1, "session %u [0x%llx]: sending unbind!", session->session_index,
	vpp_handle);
  vcl_evt (VCL_EVT_UNBIND, session);
  vppcom_send_unbind_sock (wrk, vpp_handle);

  return VPPCOM_OK;
}

static int
vppcom_session_disconnect (u32 session_handle)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  svm_msg_q_t *vpp_evt_q;
  vcl_session_t *session;
  vcl_session_state_t state;
  u64 vpp_handle;

  session = vcl_session_get_w_handle (wrk, session_handle);
  if (!session)
    return VPPCOM_EBADFD;

  vpp_handle = session->vpp_handle;
  state = session->session_state;

  VDBG (1, "session %u [0x%llx] state 0x%x (%s)", session->session_index,
	vpp_handle, state, vppcom_session_state_str (state));

  if (PREDICT_FALSE (state & STATE_LISTEN))
    {
      VDBG (0, "ERROR: Cannot disconnect a listen socket!");
      return VPPCOM_EBADFD;
    }

  if (state & STATE_VPP_CLOSING)
    {
      vpp_evt_q = vcl_session_vpp_evt_q (wrk, session);
      vcl_send_session_disconnected_reply (vpp_evt_q, wrk->my_client_index,
					   vpp_handle, 0);
      VDBG (1, "session %u [0x%llx]: sending disconnect REPLY...",
	    session->session_index, vpp_handle);
    }
  else
    {
      VDBG (1, "session %u [0x%llx]: sending disconnect...",
	    session->session_index, vpp_handle);
      vppcom_send_disconnect_session (vpp_handle);
    }

  return VPPCOM_OK;
}

/**
 * Handle app exit
 *
 * Notify vpp of the disconnect and mark the worker as free. If we're the
 * last worker, do a full cleanup otherwise, since we're probably a forked
 * child, avoid syscalls as much as possible. We might've lost privileges.
 */
void
vppcom_app_exit (void)
{
  if (!pool_elts (vcm->workers))
    return;
  vcl_worker_cleanup (vcl_worker_get_current (), 1 /* notify vpp */ );
  vcl_set_worker_index (~0);
  vcl_elog_stop (vcm);
  if (vec_len (vcm->workers) == 1)
    vl_client_disconnect_from_vlib ();
  else
    vl_client_send_disconnect (1 /* vpp should cleanup */ );
}

/*
 * VPPCOM Public API functions
 */
int
vppcom_app_create (char *app_name)
{
  vppcom_cfg_t *vcl_cfg = &vcm->cfg;
  int rv;

  if (vcm->is_init)
    {
      VDBG (1, "already initialized");
      return VPPCOM_EEXIST;
    }

  vcm->is_init = 1;
  vppcom_cfg (&vcm->cfg);
  vcl_cfg = &vcm->cfg;

  vcm->main_cpu = pthread_self ();
  vcm->main_pid = getpid ();
  vcm->app_name = format (0, "%s", app_name);
  vppcom_init_error_string_table ();
  fifo_segment_main_init (&vcm->segment_main, vcl_cfg->segment_baseva,
			  20 /* timeout in secs */ );
  pool_alloc (vcm->workers, vcl_cfg->max_workers);
  clib_spinlock_init (&vcm->workers_lock);
  clib_rwlock_init (&vcm->segment_table_lock);
  atexit (vppcom_app_exit);

  /* Allocate default worker */
  vcl_worker_alloc_and_init ();

  /* API hookup and connect to VPP */
  vppcom_api_hookup ();
  vcl_elog_init (vcm);
  vcm->app_state = STATE_APP_START;
  rv = vppcom_connect_to_vpp (app_name);
  if (rv)
    {
      VERR ("couldn't connect to VPP!");
      return rv;
    }
  VDBG (0, "sending session enable");
  rv = vppcom_app_session_enable ();
  if (rv)
    {
      VERR ("vppcom_app_session_enable() failed!");
      return rv;
    }

  VDBG (0, "sending app attach");
  rv = vppcom_app_attach ();
  if (rv)
    {
      VERR ("vppcom_app_attach() failed!");
      return rv;
    }

  VDBG (0, "app_name '%s', my_client_index %d (0x%x)", app_name,
	vcm->workers[0].my_client_index, vcm->workers[0].my_client_index);

  return VPPCOM_OK;
}

void
vppcom_app_destroy (void)
{
  int rv;
  f64 orig_app_timeout;

  if (!pool_elts (vcm->workers))
    return;

  vcl_evt (VCL_EVT_DETACH, vcm);

  if (pool_elts (vcm->workers) == 1)
    {
      vppcom_app_send_detach ();
      orig_app_timeout = vcm->cfg.app_timeout;
      vcm->cfg.app_timeout = 2.0;
      rv = vcl_wait_for_app_state_change (STATE_APP_ENABLED);
      vcm->cfg.app_timeout = orig_app_timeout;
      if (PREDICT_FALSE (rv))
	VDBG (0, "application detach timed out! returning %d (%s)", rv,
	      vppcom_retval_str (rv));
      vec_free (vcm->app_name);
      vcl_worker_cleanup (vcl_worker_get_current (), 0 /* notify vpp */ );
    }
  else
    {
      vcl_worker_cleanup (vcl_worker_get_current (), 1 /* notify vpp */ );
    }

  vcl_set_worker_index (~0);
  vcl_elog_stop (vcm);
  vl_client_disconnect_from_vlib ();
}

int
vppcom_session_create (u8 proto, u8 is_nonblocking)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *session;

  session = vcl_session_alloc (wrk);

  session->session_type = proto;
  session->session_state = STATE_START;
  session->vpp_handle = ~0;
  session->is_dgram = proto == VPPCOM_PROTO_UDP;

  if (is_nonblocking)
    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_NONBLOCK);

  vcl_evt (VCL_EVT_CREATE, session, session_type, session->session_state,
	   is_nonblocking, session_index);

  VDBG (0, "created session %u", session->session_index);

  return vcl_session_handle (session);
}

int
vcl_session_cleanup (vcl_worker_t * wrk, vcl_session_t * session,
		     vcl_session_handle_t sh, u8 do_disconnect)
{
  vcl_session_state_t state;
  u32 next_sh, vep_sh;
  int rv = VPPCOM_OK;
  u64 vpp_handle;
  u8 is_vep;

  is_vep = session->is_vep;
  next_sh = session->vep.next_sh;
  vep_sh = session->vep.vep_sh;
  state = session->session_state;
  vpp_handle = session->vpp_handle;

  VDBG (1, "session %u [0x%llx] closing", session->session_index, vpp_handle);

  if (is_vep)
    {
      while (next_sh != ~0)
	{
	  rv = vppcom_epoll_ctl (sh, EPOLL_CTL_DEL, next_sh, 0);
	  if (PREDICT_FALSE (rv < 0))
	    VDBG (0, "vpp handle 0x%llx, sh %u: EPOLL_CTL_DEL vep_idx %u"
		  " failed! rv %d (%s)", vpp_handle, next_sh, vep_sh, rv,
		  vppcom_retval_str (rv));

	  next_sh = session->vep.next_sh;
	}
    }
  else
    {
      if (session->is_vep_session)
	{
	  rv = vppcom_epoll_ctl (vep_sh, EPOLL_CTL_DEL, sh, 0);
	  if (rv < 0)
	    VDBG (0, "session %u [0x%llx]: EPOLL_CTL_DEL vep_idx %u "
		  "failed! rv %d (%s)", session->session_index, vpp_handle,
		  vep_sh, rv, vppcom_retval_str (rv));
	}

      if (!do_disconnect)
	{
	  VDBG (1, "session %u [0x%llx] disconnect skipped",
		session->session_index, vpp_handle);
	  goto cleanup;
	}

      if (state & STATE_LISTEN)
	{
	  rv = vppcom_session_unbind (sh);
	  if (PREDICT_FALSE (rv < 0))
	    VDBG (0, "session %u [0x%llx]: listener unbind failed! "
		  "rv %d (%s)", session->session_index, vpp_handle, rv,
		  vppcom_retval_str (rv));
	  return rv;
	}
      else if (state & STATE_OPEN)
	{
	  rv = vppcom_session_disconnect (sh);
	  if (PREDICT_FALSE (rv < 0))
	    VDBG (0, "ERROR: session %u [0x%llx]: disconnect failed!"
		  " rv %d (%s)", session->session_index, vpp_handle,
		  rv, vppcom_retval_str (rv));
	}
      else if (state == STATE_DISCONNECT)
	{
	  svm_msg_q_t *mq = vcl_session_vpp_evt_q (wrk, session);
	  vcl_send_session_reset_reply (mq, wrk->my_client_index,
					session->vpp_handle, 0);
	}
    }

  VDBG (0, "session %u [0x%llx] removed", session->session_index, vpp_handle);

cleanup:
  vcl_session_table_del_vpp_handle (wrk, vpp_handle);
  vcl_session_free (wrk, session);
  vcl_evt (VCL_EVT_CLOSE, session, rv);

  return rv;
}

int
vppcom_session_close (uint32_t session_handle)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *session;

  session = vcl_session_get_w_handle (wrk, session_handle);
  if (!session)
    return VPPCOM_EBADFD;
  return vcl_session_cleanup (wrk, session, session_handle,
			      1 /* do_disconnect */ );
}

int
vppcom_session_bind (uint32_t session_handle, vppcom_endpt_t * ep)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *session = 0;

  if (!ep || !ep->ip)
    return VPPCOM_EINVAL;

  session = vcl_session_get_w_handle (wrk, session_handle);
  if (!session)
    return VPPCOM_EBADFD;

  if (session->is_vep)
    {
      VDBG (0, "ERROR: cannot bind to epoll session %u!",
	    session->session_index);
      return VPPCOM_EBADFD;
    }

  session->transport.is_ip4 = ep->is_ip4;
  if (ep->is_ip4)
    clib_memcpy_fast (&session->transport.lcl_ip.ip4, ep->ip,
		      sizeof (ip4_address_t));
  else
    clib_memcpy_fast (&session->transport.lcl_ip.ip6, ep->ip,
		      sizeof (ip6_address_t));
  session->transport.lcl_port = ep->port;

  VDBG (0, "session %u handle %u: binding to local %s address %U port %u, "
	"proto %s", session->session_index, session_handle,
	session->transport.is_ip4 ? "IPv4" : "IPv6",
	format_ip46_address, &session->transport.lcl_ip,
	session->transport.is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
	clib_net_to_host_u16 (session->transport.lcl_port),
	vppcom_proto_str (session->session_type));
  vcl_evt (VCL_EVT_BIND, session);

  if (session->session_type == VPPCOM_PROTO_UDP)
    vppcom_session_listen (session_handle, 10);

  return VPPCOM_OK;
}

int
vppcom_session_listen (uint32_t listen_sh, uint32_t q_len)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *listen_session = 0;
  u64 listen_vpp_handle;
  int rv;

  listen_session = vcl_session_get_w_handle (wrk, listen_sh);
  if (!listen_session || listen_session->is_vep)
    return VPPCOM_EBADFD;

  if (q_len == 0 || q_len == ~0)
    q_len = vcm->cfg.listen_queue_size;

  listen_vpp_handle = listen_session->vpp_handle;
  if (listen_session->session_state & STATE_LISTEN)
    {
      VDBG (0, "session %u [0x%llx]: already in listen state!",
	    listen_sh, listen_vpp_handle);
      return VPPCOM_OK;
    }

  VDBG (0, "session %u [0x%llx]: sending vpp listen request...",
	listen_sh, listen_vpp_handle);

  /*
   * Send listen request to vpp and wait for reply
   */
  vppcom_send_bind_sock (listen_session);
  rv = vppcom_wait_for_session_state_change (listen_session->session_index,
					     STATE_LISTEN,
					     vcm->cfg.session_timeout);

  if (PREDICT_FALSE (rv))
    {
      listen_session = vcl_session_get_w_handle (wrk, listen_sh);
      VDBG (0, "session %u [0x%llx]: listen failed! returning %d (%s)",
	    listen_sh, listen_session->vpp_handle, rv,
	    vppcom_retval_str (rv));
      return rv;
    }

  return VPPCOM_OK;
}

int
vppcom_session_tls_add_cert (uint32_t session_handle, char *cert,
			     uint32_t cert_len)
{

  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *session = 0;

  session = vcl_session_get_w_handle (wrk, session_handle);
  if (!session)
    return VPPCOM_EBADFD;

  if (cert_len == 0 || cert_len == ~0)
    return VPPCOM_EBADFD;

  /*
   * Send listen request to vpp and wait for reply
   */
  vppcom_send_application_tls_cert_add (session, cert, cert_len);

  return VPPCOM_OK;

}

int
vppcom_session_tls_add_key (uint32_t session_handle, char *key,
			    uint32_t key_len)
{

  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *session = 0;

  session = vcl_session_get_w_handle (wrk, session_handle);
  if (!session)
    return VPPCOM_EBADFD;

  if (key_len == 0 || key_len == ~0)
    return VPPCOM_EBADFD;

  /*
   * Send listen request to vpp and wait for reply
   */
  vppcom_send_application_tls_key_add (session, key, key_len);

  return VPPCOM_OK;


}

static int
validate_args_session_accept_ (vcl_worker_t * wrk, vcl_session_t * ls)
{
  if (ls->is_vep)
    {
      VDBG (0, "ERROR: cannot accept on epoll session %u!",
	    ls->session_index);
      return VPPCOM_EBADFD;
    }

  if (ls->session_state != STATE_LISTEN)
    {
      VDBG (0, "ERROR: session [0x%llx]: not in listen state! state 0x%x"
	    " (%s)", ls->vpp_handle, ls->session_index, ls->session_state,
	    vppcom_session_state_str (ls->session_state));
      return VPPCOM_EBADFD;
    }
  return VPPCOM_OK;
}

int
vppcom_session_accept (uint32_t listen_session_handle, vppcom_endpt_t * ep,
		       uint32_t flags)
{
  u32 client_session_index = ~0, listen_session_index, accept_flags = 0;
  vcl_worker_t *wrk = vcl_worker_get_current ();
  session_accepted_msg_t accepted_msg;
  vcl_session_t *listen_session = 0;
  vcl_session_t *client_session = 0;
  vcl_session_msg_t *evt;
  svm_msg_q_msg_t msg;
  session_event_t *e;
  u8 is_nonblocking;
  int rv;

  listen_session = vcl_session_get_w_handle (wrk, listen_session_handle);
  if (!listen_session)
    return VPPCOM_EBADFD;

  listen_session_index = listen_session->session_index;
  if ((rv = validate_args_session_accept_ (wrk, listen_session)))
    return rv;

  if (clib_fifo_elts (listen_session->accept_evts_fifo))
    {
      clib_fifo_sub2 (listen_session->accept_evts_fifo, evt);
      accept_flags = evt->flags;
      accepted_msg = evt->accepted_msg;
      goto handle;
    }

  is_nonblocking = VCL_SESS_ATTR_TEST (listen_session->attr,
				       VCL_SESS_ATTR_NONBLOCK);
  if (svm_msg_q_is_empty (wrk->app_event_queue) && is_nonblocking)
    return VPPCOM_EAGAIN;

  while (1)
    {
      if (svm_msg_q_sub (wrk->app_event_queue, &msg, SVM_Q_WAIT, 0))
	return VPPCOM_EAGAIN;

      e = svm_msg_q_msg_data (wrk->app_event_queue, &msg);
      if (e->event_type != SESSION_CTRL_EVT_ACCEPTED)
	{
	  VDBG (0, "discarded event: %u", e->event_type);
	  svm_msg_q_free_msg (wrk->app_event_queue, &msg);
	  continue;
	}
      clib_memcpy_fast (&accepted_msg, e->data, sizeof (accepted_msg));
      svm_msg_q_free_msg (wrk->app_event_queue, &msg);
      break;
    }

handle:

  client_session_index = vcl_session_accepted_handler (wrk, &accepted_msg,
						       listen_session_index);
  if (client_session_index == VCL_INVALID_SESSION_INDEX)
    return VPPCOM_ECONNABORTED;

  listen_session = vcl_session_get (wrk, listen_session_index);
  client_session = vcl_session_get (wrk, client_session_index);

  if (flags & O_NONBLOCK)
    VCL_SESS_ATTR_SET (client_session->attr, VCL_SESS_ATTR_NONBLOCK);

  VDBG (1, "listener %u [0x%llx]: Got a connect request! session %u [0x%llx],"
	" flags %d, is_nonblocking %u", listen_session->session_index,
	listen_session->vpp_handle, client_session_index,
	client_session->vpp_handle, flags,
	VCL_SESS_ATTR_TEST (client_session->attr, VCL_SESS_ATTR_NONBLOCK));

  if (ep)
    {
      ep->is_ip4 = client_session->transport.is_ip4;
      ep->port = client_session->transport.rmt_port;
      if (client_session->transport.is_ip4)
	clib_memcpy_fast (ep->ip, &client_session->transport.rmt_ip.ip4,
			  sizeof (ip4_address_t));
      else
	clib_memcpy_fast (ep->ip, &client_session->transport.rmt_ip.ip6,
			  sizeof (ip6_address_t));
    }

  VDBG (0, "listener %u [0x%llx] accepted %u [0x%llx] peer: %U:%u "
	"local: %U:%u", listen_session_handle, listen_session->vpp_handle,
	client_session_index, client_session->vpp_handle,
	format_ip46_address, &client_session->transport.rmt_ip,
	client_session->transport.is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
	clib_net_to_host_u16 (client_session->transport.rmt_port),
	format_ip46_address, &client_session->transport.lcl_ip,
	client_session->transport.is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
	clib_net_to_host_u16 (client_session->transport.lcl_port));
  vcl_evt (VCL_EVT_ACCEPT, client_session, listen_session,
	   client_session_index);

  /*
   * Session might have been closed already
   */
  if (accept_flags)
    {
      if (accept_flags & VCL_ACCEPTED_F_CLOSED)
	client_session->session_state = STATE_VPP_CLOSING;
      else if (accept_flags & VCL_ACCEPTED_F_RESET)
	client_session->session_state = STATE_DISCONNECT;
    }
  return vcl_session_handle (client_session);
}

int
vppcom_session_connect (uint32_t session_handle, vppcom_endpt_t * server_ep)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *session = 0;
  u32 session_index;
  int rv;

  session = vcl_session_get_w_handle (wrk, session_handle);
  if (!session)
    return VPPCOM_EBADFD;
  session_index = session->session_index;

  if (PREDICT_FALSE (session->is_vep))
    {
      VDBG (0, "ERROR: cannot connect epoll session %u!",
	    session->session_index);
      return VPPCOM_EBADFD;
    }

  if (PREDICT_FALSE (session->session_state & CLIENT_STATE_OPEN))
    {
      VDBG (0, "session handle %u [0x%llx]: session already "
	    "connected to %s %U port %d proto %s, state 0x%x (%s)",
	    session_handle, session->vpp_handle,
	    session->transport.is_ip4 ? "IPv4" : "IPv6",
	    format_ip46_address,
	    &session->transport.rmt_ip, session->transport.is_ip4 ?
	    IP46_TYPE_IP4 : IP46_TYPE_IP6,
	    clib_net_to_host_u16 (session->transport.rmt_port),
	    vppcom_proto_str (session->session_type), session->session_state,
	    vppcom_session_state_str (session->session_state));
      return VPPCOM_OK;
    }

  session->transport.is_ip4 = server_ep->is_ip4;
  if (session->transport.is_ip4)
    clib_memcpy_fast (&session->transport.rmt_ip.ip4, server_ep->ip,
		      sizeof (ip4_address_t));
  else
    clib_memcpy_fast (&session->transport.rmt_ip.ip6, server_ep->ip,
		      sizeof (ip6_address_t));
  session->transport.rmt_port = server_ep->port;

  VDBG (0, "session handle %u [0x%llx]: connecting to server %s %U "
	"port %d proto %s", session_handle, session->vpp_handle,
	session->transport.is_ip4 ? "IPv4" : "IPv6",
	format_ip46_address,
	&session->transport.rmt_ip, session->transport.is_ip4 ?
	IP46_TYPE_IP4 : IP46_TYPE_IP6,
	clib_net_to_host_u16 (session->transport.rmt_port),
	vppcom_proto_str (session->session_type));

  /*
   * Send connect request and wait for reply from vpp
   */
  vppcom_send_connect_sock (session);
  rv = vppcom_wait_for_session_state_change (session_index, STATE_CONNECT,
					     vcm->cfg.session_timeout);

  session = vcl_session_get (wrk, session_index);
  VDBG (0, "session %u [0x%llx]: connect %s!", session->session_index,
	session->vpp_handle, rv ? "failed" : "succeeded");

  return rv;
}

static u8
vcl_is_rx_evt_for_session (session_event_t * e, u32 sid, u8 is_ct)
{
  return (e->event_type == SESSION_IO_EVT_RX && e->session_index == sid);
}

static inline int
vppcom_session_read_internal (uint32_t session_handle, void *buf, int n,
			      u8 peek)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  int n_read = 0, is_nonblocking;
  vcl_session_t *s = 0;
  svm_fifo_t *rx_fifo;
  svm_msg_q_msg_t msg;
  session_event_t *e;
  svm_msg_q_t *mq;
  u8 is_ct;

  if (PREDICT_FALSE (!buf))
    return VPPCOM_EINVAL;

  s = vcl_session_get_w_handle (wrk, session_handle);
  if (PREDICT_FALSE (!s || s->is_vep))
    return VPPCOM_EBADFD;

  if (PREDICT_FALSE (!vcl_session_is_open (s)))
    {
      VDBG (0, "session %u[0x%llx] is not open! state 0x%x (%s)",
	    s->session_index, s->vpp_handle, s->session_state,
	    vppcom_session_state_str (s->session_state));
      return vcl_session_closed_error (s);
    }

  is_nonblocking = VCL_SESS_ATTR_TEST (s->attr, VCL_SESS_ATTR_NONBLOCK);
  is_ct = vcl_session_is_ct (s);
  mq = wrk->app_event_queue;
  rx_fifo = is_ct ? s->ct_rx_fifo : s->rx_fifo;
  s->has_rx_evt = 0;

  if (svm_fifo_is_empty_cons (rx_fifo))
    {
      if (is_nonblocking)
	{
	  svm_fifo_unset_event (s->rx_fifo);
	  return VPPCOM_EWOULDBLOCK;
	}
      while (svm_fifo_is_empty_cons (rx_fifo))
	{
	  if (vcl_session_is_closing (s))
	    return vcl_session_closing_error (s);

	  svm_fifo_unset_event (s->rx_fifo);
	  svm_msg_q_lock (mq);
	  if (svm_msg_q_is_empty (mq))
	    svm_msg_q_wait (mq);

	  svm_msg_q_sub_w_lock (mq, &msg);
	  e = svm_msg_q_msg_data (mq, &msg);
	  svm_msg_q_unlock (mq);
	  if (!vcl_is_rx_evt_for_session (e, s->session_index, is_ct))
	    vcl_handle_mq_event (wrk, e);
	  svm_msg_q_free_msg (mq, &msg);
	}
    }

  if (s->is_dgram)
    n_read = app_recv_dgram_raw (rx_fifo, buf, n, &s->transport, 0, peek);
  else
    n_read = app_recv_stream_raw (rx_fifo, buf, n, 0, peek);

  if (svm_fifo_is_empty_cons (rx_fifo))
    svm_fifo_unset_event (s->rx_fifo);

  /* Cut-through sessions might request tx notifications on rx fifos */
  if (PREDICT_FALSE (rx_fifo->want_deq_ntf))
    {
      app_send_io_evt_to_vpp (s->vpp_evt_q, s->rx_fifo->master_session_index,
			      SESSION_IO_EVT_RX, SVM_Q_WAIT);
      svm_fifo_reset_has_deq_ntf (s->rx_fifo);
    }

  VDBG (2, "session %u[0x%llx]: read %d bytes from (%p)", s->session_index,
	s->vpp_handle, n_read, rx_fifo);

  return n_read;
}

int
vppcom_session_read (uint32_t session_handle, void *buf, size_t n)
{
  return (vppcom_session_read_internal (session_handle, buf, n, 0));
}

static int
vppcom_session_peek (uint32_t session_handle, void *buf, int n)
{
  return (vppcom_session_read_internal (session_handle, buf, n, 1));
}

int
vppcom_session_read_segments (uint32_t session_handle,
			      vppcom_data_segments_t ds)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  int n_read = 0, is_nonblocking;
  vcl_session_t *s = 0;
  svm_fifo_t *rx_fifo;
  svm_msg_q_msg_t msg;
  session_event_t *e;
  svm_msg_q_t *mq;
  u8 is_ct;

  s = vcl_session_get_w_handle (wrk, session_handle);
  if (PREDICT_FALSE (!s || s->is_vep))
    return VPPCOM_EBADFD;

  if (PREDICT_FALSE (!vcl_session_is_open (s)))
    return vcl_session_closed_error (s);

  is_nonblocking = VCL_SESS_ATTR_TEST (s->attr, VCL_SESS_ATTR_NONBLOCK);
  is_ct = vcl_session_is_ct (s);
  mq = is_ct ? s->our_evt_q : wrk->app_event_queue;
  rx_fifo = s->rx_fifo;
  s->has_rx_evt = 0;

  if (is_ct)
    svm_fifo_unset_event (s->rx_fifo);

  if (svm_fifo_is_empty_cons (rx_fifo))
    {
      if (is_nonblocking)
	{
	  svm_fifo_unset_event (rx_fifo);
	  return VPPCOM_EWOULDBLOCK;
	}
      while (svm_fifo_is_empty_cons (rx_fifo))
	{
	  if (vcl_session_is_closing (s))
	    return vcl_session_closing_error (s);

	  svm_fifo_unset_event (rx_fifo);
	  svm_msg_q_lock (mq);
	  if (svm_msg_q_is_empty (mq))
	    svm_msg_q_wait (mq);

	  svm_msg_q_sub_w_lock (mq, &msg);
	  e = svm_msg_q_msg_data (mq, &msg);
	  svm_msg_q_unlock (mq);
	  if (!vcl_is_rx_evt_for_session (e, s->session_index, is_ct))
	    vcl_handle_mq_event (wrk, e);
	  svm_msg_q_free_msg (mq, &msg);
	}
    }

  n_read = svm_fifo_segments (rx_fifo, (svm_fifo_seg_t *) ds);
  svm_fifo_unset_event (rx_fifo);

  return n_read;
}

void
vppcom_session_free_segments (uint32_t session_handle,
			      vppcom_data_segments_t ds)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *s;

  s = vcl_session_get_w_handle (wrk, session_handle);
  if (PREDICT_FALSE (!s || s->is_vep))
    return;

  svm_fifo_segments_free (s->rx_fifo, (svm_fifo_seg_t *) ds);
}

int
vppcom_data_segment_copy (void *buf, vppcom_data_segments_t ds, u32 max_bytes)
{
  u32 first_copy = clib_min (ds[0].len, max_bytes);
  clib_memcpy_fast (buf, ds[0].data, first_copy);
  if (first_copy < max_bytes)
    {
      clib_memcpy_fast (buf + first_copy, ds[1].data,
			clib_min (ds[1].len, max_bytes - first_copy));
    }
  return 0;
}

static u8
vcl_is_tx_evt_for_session (session_event_t * e, u32 sid, u8 is_ct)
{
  return (e->event_type == SESSION_IO_EVT_TX && e->session_index == sid);
}

static inline int
vppcom_session_write_inline (uint32_t session_handle, void *buf, size_t n,
			     u8 is_flush)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  int n_write, is_nonblocking;
  vcl_session_t *s = 0;
  session_evt_type_t et;
  svm_msg_q_msg_t msg;
  svm_fifo_t *tx_fifo;
  session_event_t *e;
  svm_msg_q_t *mq;
  u8 is_ct;

  if (PREDICT_FALSE (!buf))
    return VPPCOM_EINVAL;

  s = vcl_session_get_w_handle (wrk, session_handle);
  if (PREDICT_FALSE (!s))
    return VPPCOM_EBADFD;

  if (PREDICT_FALSE (s->is_vep))
    {
      VDBG (0, "ERROR: session %u [0x%llx]: cannot write to an epoll"
	    " session!", s->session_index, s->vpp_handle);
      return VPPCOM_EBADFD;
    }

  if (PREDICT_FALSE (!vcl_session_is_open (s)))
    {
      VDBG (1, "session %u [0x%llx]: is not open! state 0x%x (%s)",
	    s->session_index, s->vpp_handle, s->session_state,
	    vppcom_session_state_str (s->session_state));
      return vcl_session_closed_error (s);;
    }

  is_ct = vcl_session_is_ct (s);
  tx_fifo = is_ct ? s->ct_tx_fifo : s->tx_fifo;
  is_nonblocking = VCL_SESS_ATTR_TEST (s->attr, VCL_SESS_ATTR_NONBLOCK);

  mq = wrk->app_event_queue;
  if (svm_fifo_is_full_prod (tx_fifo))
    {
      if (is_nonblocking)
	{
	  return VPPCOM_EWOULDBLOCK;
	}
      while (svm_fifo_is_full_prod (tx_fifo))
	{
	  svm_fifo_add_want_deq_ntf (tx_fifo, SVM_FIFO_WANT_DEQ_NOTIF);
	  if (vcl_session_is_closing (s))
	    return vcl_session_closing_error (s);
	  svm_msg_q_lock (mq);
	  if (svm_msg_q_is_empty (mq))
	    svm_msg_q_wait (mq);

	  svm_msg_q_sub_w_lock (mq, &msg);
	  e = svm_msg_q_msg_data (mq, &msg);
	  svm_msg_q_unlock (mq);

	  if (!vcl_is_tx_evt_for_session (e, s->session_index, is_ct))
	    vcl_handle_mq_event (wrk, e);
	  svm_msg_q_free_msg (mq, &msg);
	}
    }

  et = SESSION_IO_EVT_TX;
  if (is_flush && !is_ct)
    et = SESSION_IO_EVT_TX_FLUSH;

  if (s->is_dgram)
    n_write = app_send_dgram_raw (tx_fifo, &s->transport,
				  s->vpp_evt_q, buf, n, et,
				  0 /* do_evt */ , SVM_Q_WAIT);
  else
    n_write = app_send_stream_raw (tx_fifo, s->vpp_evt_q, buf, n, et,
				   0 /* do_evt */ , SVM_Q_WAIT);

  if (svm_fifo_set_event (s->tx_fifo))
    app_send_io_evt_to_vpp (s->vpp_evt_q, s->tx_fifo->master_session_index,
			    et, SVM_Q_WAIT);

  ASSERT (n_write > 0);

  VDBG (2, "session %u [0x%llx]: wrote %d bytes", s->session_index,
	s->vpp_handle, n_write);

  return n_write;
}

int
vppcom_session_write (uint32_t session_handle, void *buf, size_t n)
{
  return vppcom_session_write_inline (session_handle, buf, n,
				      0 /* is_flush */ );
}

int
vppcom_session_write_msg (uint32_t session_handle, void *buf, size_t n)
{
  return vppcom_session_write_inline (session_handle, buf, n,
				      1 /* is_flush */ );
}

#define vcl_fifo_rx_evt_valid_or_break(_s)				\
if (PREDICT_FALSE (svm_fifo_is_empty (_s->rx_fifo)))			\
  {									\
    if (!vcl_session_is_ct (_s))					\
      {									\
	svm_fifo_unset_event (_s->rx_fifo);				\
	if (svm_fifo_is_empty (_s->rx_fifo))				\
	  break;							\
      }									\
    else if (svm_fifo_is_empty (_s->ct_rx_fifo))			\
      {									\
	svm_fifo_unset_event (_s->ct_rx_fifo);				\
	if (svm_fifo_is_empty (_s->ct_rx_fifo))				\
	  break;							\
      }									\
  }									\

static void
vcl_select_handle_mq_event (vcl_worker_t * wrk, session_event_t * e,
			    unsigned long n_bits, unsigned long *read_map,
			    unsigned long *write_map,
			    unsigned long *except_map, u32 * bits_set)
{
  session_disconnected_msg_t *disconnected_msg;
  session_connected_msg_t *connected_msg;
  vcl_session_t *session;
  u32 sid;

  switch (e->event_type)
    {
    case SESSION_IO_EVT_RX:
      sid = e->session_index;
      session = vcl_session_get (wrk, sid);
      if (!session)
	break;
      vcl_fifo_rx_evt_valid_or_break (session);
      if (sid < n_bits && read_map)
	{
	  clib_bitmap_set_no_check ((uword *) read_map, sid, 1);
	  *bits_set += 1;
	}
      break;
    case SESSION_IO_EVT_TX:
      sid = e->session_index;
      session = vcl_session_get (wrk, sid);
      if (!session)
	break;
      if (sid < n_bits && write_map)
	{
	  clib_bitmap_set_no_check ((uword *) write_map, sid, 1);
	  *bits_set += 1;
	}
      break;
    case SESSION_CTRL_EVT_ACCEPTED:
      session = vcl_session_accepted (wrk,
				      (session_accepted_msg_t *) e->data);
      if (!session)
	break;
      sid = session->session_index;
      if (sid < n_bits && read_map)
	{
	  clib_bitmap_set_no_check ((uword *) read_map, sid, 1);
	  *bits_set += 1;
	}
      break;
    case SESSION_CTRL_EVT_CONNECTED:
      connected_msg = (session_connected_msg_t *) e->data;
      vcl_session_connected_handler (wrk, connected_msg);
      break;
    case SESSION_CTRL_EVT_DISCONNECTED:
      disconnected_msg = (session_disconnected_msg_t *) e->data;
      session = vcl_session_disconnected_handler (wrk, disconnected_msg);
      if (!session)
	break;
      sid = session->session_index;
      if (sid < n_bits && except_map)
	{
	  clib_bitmap_set_no_check ((uword *) except_map, sid, 1);
	  *bits_set += 1;
	}
      break;
    case SESSION_CTRL_EVT_RESET:
      sid = vcl_session_reset_handler (wrk, (session_reset_msg_t *) e->data);
      if (sid < n_bits && except_map)
	{
	  clib_bitmap_set_no_check ((uword *) except_map, sid, 1);
	  *bits_set += 1;
	}
      break;
    case SESSION_CTRL_EVT_UNLISTEN_REPLY:
      vcl_session_unlisten_reply_handler (wrk, e->data);
      break;
    case SESSION_CTRL_EVT_WORKER_UPDATE_REPLY:
      vcl_session_worker_update_reply_handler (wrk, e->data);
      break;
    case SESSION_CTRL_EVT_REQ_WORKER_UPDATE:
      vcl_session_req_worker_update_handler (wrk, e->data);
      break;
    default:
      clib_warning ("unhandled: %u", e->event_type);
      break;
    }
}

static int
vcl_select_handle_mq (vcl_worker_t * wrk, svm_msg_q_t * mq,
		      unsigned long n_bits, unsigned long *read_map,
		      unsigned long *write_map, unsigned long *except_map,
		      double time_to_wait, u32 * bits_set)
{
  svm_msg_q_msg_t *msg;
  session_event_t *e;
  u32 i;

  svm_msg_q_lock (mq);
  if (svm_msg_q_is_empty (mq))
    {
      if (*bits_set)
	{
	  svm_msg_q_unlock (mq);
	  return 0;
	}

      if (!time_to_wait)
	{
	  svm_msg_q_unlock (mq);
	  return 0;
	}
      else if (time_to_wait < 0)
	{
	  svm_msg_q_wait (mq);
	}
      else
	{
	  if (svm_msg_q_timedwait (mq, time_to_wait))
	    {
	      svm_msg_q_unlock (mq);
	      return 0;
	    }
	}
    }
  vcl_mq_dequeue_batch (wrk, mq, ~0);
  svm_msg_q_unlock (mq);

  for (i = 0; i < vec_len (wrk->mq_msg_vector); i++)
    {
      msg = vec_elt_at_index (wrk->mq_msg_vector, i);
      e = svm_msg_q_msg_data (mq, msg);
      vcl_select_handle_mq_event (wrk, e, n_bits, read_map, write_map,
				  except_map, bits_set);
      svm_msg_q_free_msg (mq, msg);
    }
  vec_reset_length (wrk->mq_msg_vector);
  vcl_handle_pending_wrk_updates (wrk);
  return *bits_set;
}

static int
vppcom_select_condvar (vcl_worker_t * wrk, int n_bits,
		       vcl_si_set * read_map, vcl_si_set * write_map,
		       vcl_si_set * except_map, double time_to_wait,
		       u32 * bits_set)
{
  double wait = 0, start = 0;

  if (!*bits_set)
    {
      wait = time_to_wait;
      start = clib_time_now (&wrk->clib_time);
    }

  do
    {
      vcl_select_handle_mq (wrk, wrk->app_event_queue, n_bits, read_map,
			    write_map, except_map, wait, bits_set);
      if (*bits_set)
	return *bits_set;
      if (wait == -1)
	continue;

      wait = wait - (clib_time_now (&wrk->clib_time) - start);
    }
  while (wait > 0);

  return 0;
}

static int
vppcom_select_eventfd (vcl_worker_t * wrk, int n_bits,
		       vcl_si_set * read_map, vcl_si_set * write_map,
		       vcl_si_set * except_map, double time_to_wait,
		       u32 * bits_set)
{
  vcl_mq_evt_conn_t *mqc;
  int __clib_unused n_read;
  int n_mq_evts, i;
  u64 buf;

  vec_validate (wrk->mq_events, pool_elts (wrk->mq_evt_conns));
  n_mq_evts = epoll_wait (wrk->mqs_epfd, wrk->mq_events,
			  vec_len (wrk->mq_events), time_to_wait);
  for (i = 0; i < n_mq_evts; i++)
    {
      mqc = vcl_mq_evt_conn_get (wrk, wrk->mq_events[i].data.u32);
      n_read = read (mqc->mq_fd, &buf, sizeof (buf));
      vcl_select_handle_mq (wrk, mqc->mq, n_bits, read_map, write_map,
			    except_map, 0, bits_set);
    }

  return (n_mq_evts > 0 ? (int) *bits_set : 0);
}

int
vppcom_select (int n_bits, vcl_si_set * read_map, vcl_si_set * write_map,
	       vcl_si_set * except_map, double time_to_wait)
{
  u32 sid, minbits = clib_max (n_bits, BITS (uword)), bits_set = 0;
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *session = 0;
  int rv, i;

  if (n_bits && read_map)
    {
      clib_bitmap_validate (wrk->rd_bitmap, minbits);
      clib_memcpy_fast (wrk->rd_bitmap, read_map,
			vec_len (wrk->rd_bitmap) * sizeof (vcl_si_set));
      memset (read_map, 0, vec_len (wrk->rd_bitmap) * sizeof (vcl_si_set));
    }
  if (n_bits && write_map)
    {
      clib_bitmap_validate (wrk->wr_bitmap, minbits);
      clib_memcpy_fast (wrk->wr_bitmap, write_map,
			vec_len (wrk->wr_bitmap) * sizeof (vcl_si_set));
      memset (write_map, 0, vec_len (wrk->wr_bitmap) * sizeof (vcl_si_set));
    }
  if (n_bits && except_map)
    {
      clib_bitmap_validate (wrk->ex_bitmap, minbits);
      clib_memcpy_fast (wrk->ex_bitmap, except_map,
			vec_len (wrk->ex_bitmap) * sizeof (vcl_si_set));
      memset (except_map, 0, vec_len (wrk->ex_bitmap) * sizeof (vcl_si_set));
    }

  if (!n_bits)
    return 0;

  if (!write_map)
    goto check_rd;

  /* *INDENT-OFF* */
  clib_bitmap_foreach (sid, wrk->wr_bitmap, ({
    if (!(session = vcl_session_get (wrk, sid)))
      {
        if (except_map && sid < minbits)
          clib_bitmap_set_no_check (except_map, sid, 1);
        continue;
      }

    rv = svm_fifo_is_full_prod (session->tx_fifo);
    if (!rv)
      {
        clib_bitmap_set_no_check ((uword*)write_map, sid, 1);
        bits_set++;
      }
    else
      svm_fifo_add_want_deq_ntf (session->tx_fifo, SVM_FIFO_WANT_DEQ_NOTIF);
  }));

check_rd:
  if (!read_map)
    goto check_mq;

  clib_bitmap_foreach (sid, wrk->rd_bitmap, ({
    if (!(session = vcl_session_get (wrk, sid)))
      {
        if (except_map && sid < minbits)
          clib_bitmap_set_no_check (except_map, sid, 1);
        continue;
      }

    rv = vcl_session_read_ready (session);
    if (rv)
      {
        clib_bitmap_set_no_check ((uword*)read_map, sid, 1);
        bits_set++;
      }
  }));
  /* *INDENT-ON* */

check_mq:

  for (i = 0; i < vec_len (wrk->unhandled_evts_vector); i++)
    {
      vcl_select_handle_mq_event (wrk, &wrk->unhandled_evts_vector[i], n_bits,
				  read_map, write_map, except_map, &bits_set);
    }
  vec_reset_length (wrk->unhandled_evts_vector);

  if (vcm->cfg.use_mq_eventfd)
    vppcom_select_eventfd (wrk, n_bits, read_map, write_map, except_map,
			   time_to_wait, &bits_set);
  else
    vppcom_select_condvar (wrk, n_bits, read_map, write_map, except_map,
			   time_to_wait, &bits_set);

  return (bits_set);
}

static inline void
vep_verify_epoll_chain (vcl_worker_t * wrk, u32 vep_idx)
{
  vcl_session_t *session;
  vppcom_epoll_t *vep;
  u32 sid = vep_idx;

  if (VPPCOM_DEBUG <= 2)
    return;

  session = vcl_session_get (wrk, vep_idx);
  if (PREDICT_FALSE (!session))
    {
      VDBG (0, "ERROR: Invalid vep_idx (%u)!", vep_idx);
      goto done;
    }
  if (PREDICT_FALSE (!session->is_vep))
    {
      VDBG (0, "ERROR: vep_idx (%u) is not a vep!", vep_idx);
      goto done;
    }
  vep = &session->vep;
  VDBG (0, "vep_idx (%u): Dumping epoll chain\n"
	"{\n"
	"   is_vep         = %u\n"
	"   is_vep_session = %u\n"
	"   next_sid       = 0x%x (%u)\n"
	"}\n", vep_idx, session->is_vep, session->is_vep_session,
	vep->next_sh, vep->next_sh);

  for (sid = vep->next_sh; sid != ~0; sid = vep->next_sh)
    {
      session = vcl_session_get (wrk, sid);
      if (PREDICT_FALSE (!session))
	{
	  VDBG (0, "ERROR: Invalid sid (%u)!", sid);
	  goto done;
	}
      if (PREDICT_FALSE (session->is_vep))
	{
	  VDBG (0, "ERROR: sid (%u) is a vep!", vep_idx);
	}
      else if (PREDICT_FALSE (!session->is_vep_session))
	{
	  VDBG (0, "ERROR: session (%u) is not a vep session!", sid);
	  goto done;
	}
      vep = &session->vep;
      if (PREDICT_FALSE (vep->vep_sh != vep_idx))
	VDBG (0, "ERROR: session (%u) vep_idx (%u) != vep_idx (%u)!",
	      sid, session->vep.vep_sh, vep_idx);
      if (session->is_vep_session)
	{
	  VDBG (0, "vep_idx[%u]: sid 0x%x (%u)\n"
		"{\n"
		"   next_sid       = 0x%x (%u)\n"
		"   prev_sid       = 0x%x (%u)\n"
		"   vep_idx        = 0x%x (%u)\n"
		"   ev.events      = 0x%x\n"
		"   ev.data.u64    = 0x%llx\n"
		"   et_mask        = 0x%x\n"
		"}\n",
		vep_idx, sid, sid, vep->next_sh, vep->next_sh, vep->prev_sh,
		vep->prev_sh, vep->vep_sh, vep->vep_sh, vep->ev.events,
		vep->ev.data.u64, vep->et_mask);
	}
    }

done:
  VDBG (0, "vep_idx (%u): Dump complete!\n", vep_idx);
}

int
vppcom_epoll_create (void)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *vep_session;

  vep_session = vcl_session_alloc (wrk);

  vep_session->is_vep = 1;
  vep_session->vep.vep_sh = ~0;
  vep_session->vep.next_sh = ~0;
  vep_session->vep.prev_sh = ~0;
  vep_session->vpp_handle = ~0;

  vcl_evt (VCL_EVT_EPOLL_CREATE, vep_session, vep_session->session_index);
  VDBG (0, "Created vep_idx %u", vep_session->session_index);

  return vcl_session_handle (vep_session);
}

int
vppcom_epoll_ctl (uint32_t vep_handle, int op, uint32_t session_handle,
		  struct epoll_event *event)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *vep_session;
  vcl_session_t *session;
  int rv = VPPCOM_OK;

  if (vep_handle == session_handle)
    {
      VDBG (0, "vep_sh == session handle (%u)!", vep_handle);
      return VPPCOM_EINVAL;
    }

  vep_session = vcl_session_get_w_handle (wrk, vep_handle);
  if (PREDICT_FALSE (!vep_session))
    {
      VDBG (0, "Invalid vep_sh (%u)!", vep_handle);
      return VPPCOM_EBADFD;
    }
  if (PREDICT_FALSE (!vep_session->is_vep))
    {
      VDBG (0, "vep_sh (%u) is not a vep!", vep_handle);
      return VPPCOM_EINVAL;
    }

  ASSERT (vep_session->vep.vep_sh == ~0);
  ASSERT (vep_session->vep.prev_sh == ~0);

  session = vcl_session_get_w_handle (wrk, session_handle);
  if (PREDICT_FALSE (!session))
    {
      VDBG (0, "Invalid session_handle (%u)!", session_handle);
      return VPPCOM_EBADFD;
    }
  if (PREDICT_FALSE (session->is_vep))
    {
      VDBG (0, "session_handle (%u) is a vep!", vep_handle);
      return VPPCOM_EINVAL;
    }

  switch (op)
    {
    case EPOLL_CTL_ADD:
      if (PREDICT_FALSE (!event))
	{
	  VDBG (0, "EPOLL_CTL_ADD: NULL pointer to epoll_event structure!");
	  return VPPCOM_EINVAL;
	}
      if (vep_session->vep.next_sh != ~0)
	{
	  vcl_session_t *next_session;
	  next_session = vcl_session_get_w_handle (wrk,
						   vep_session->vep.next_sh);
	  if (PREDICT_FALSE (!next_session))
	    {
	      VDBG (0, "EPOLL_CTL_ADD: Invalid vep.next_sh (%u) on "
		    "vep_idx (%u)!", vep_session->vep.next_sh, vep_handle);
	      return VPPCOM_EBADFD;
	    }
	  ASSERT (next_session->vep.prev_sh == vep_handle);
	  next_session->vep.prev_sh = session_handle;
	}
      session->vep.next_sh = vep_session->vep.next_sh;
      session->vep.prev_sh = vep_handle;
      session->vep.vep_sh = vep_handle;
      session->vep.et_mask = VEP_DEFAULT_ET_MASK;
      session->vep.ev = *event;
      session->is_vep = 0;
      session->is_vep_session = 1;
      vep_session->vep.next_sh = session_handle;

      if (session->tx_fifo)
	svm_fifo_add_want_deq_ntf (session->tx_fifo,
				   SVM_FIFO_WANT_DEQ_NOTIF_IF_FULL);

      VDBG (1, "EPOLL_CTL_ADD: vep_sh %u, sh %u, events 0x%x, data 0x%llx!",
	    vep_handle, session_handle, event->events, event->data.u64);
      vcl_evt (VCL_EVT_EPOLL_CTLADD, session, event->events, event->data.u64);
      break;

    case EPOLL_CTL_MOD:
      if (PREDICT_FALSE (!event))
	{
	  VDBG (0, "EPOLL_CTL_MOD: NULL pointer to epoll_event structure!");
	  rv = VPPCOM_EINVAL;
	  goto done;
	}
      else if (PREDICT_FALSE (!session->is_vep_session))
	{
	  VDBG (0, "sh %u EPOLL_CTL_MOD: not a vep session!", session_handle);
	  rv = VPPCOM_EINVAL;
	  goto done;
	}
      else if (PREDICT_FALSE (session->vep.vep_sh != vep_handle))
	{
	  VDBG (0, "EPOLL_CTL_MOD: sh %u vep_sh (%u) != vep_sh (%u)!",
		session_handle, session->vep.vep_sh, vep_handle);
	  rv = VPPCOM_EINVAL;
	  goto done;
	}
      session->vep.et_mask = VEP_DEFAULT_ET_MASK;
      session->vep.ev = *event;
      VDBG (1, "EPOLL_CTL_MOD: vep_sh %u, sh %u, events 0x%x, data 0x%llx!",
	    vep_handle, session_handle, event->events, event->data.u64);
      break;

    case EPOLL_CTL_DEL:
      if (PREDICT_FALSE (!session->is_vep_session))
	{
	  VDBG (0, "EPOLL_CTL_DEL: %u not a vep session!", session_handle);
	  rv = VPPCOM_EINVAL;
	  goto done;
	}
      else if (PREDICT_FALSE (session->vep.vep_sh != vep_handle))
	{
	  VDBG (0, "EPOLL_CTL_DEL: sh %u vep_sh (%u) != vep_sh (%u)!",
		session_handle, session->vep.vep_sh, vep_handle);
	  rv = VPPCOM_EINVAL;
	  goto done;
	}

      if (session->vep.prev_sh == vep_handle)
	vep_session->vep.next_sh = session->vep.next_sh;
      else
	{
	  vcl_session_t *prev_session;
	  prev_session = vcl_session_get_w_handle (wrk, session->vep.prev_sh);
	  if (PREDICT_FALSE (!prev_session))
	    {
	      VDBG (0, "EPOLL_CTL_DEL: Invalid prev_sh (%u) on sh (%u)!",
		    session->vep.prev_sh, session_handle);
	      return VPPCOM_EBADFD;
	    }
	  ASSERT (prev_session->vep.next_sh == session_handle);
	  prev_session->vep.next_sh = session->vep.next_sh;
	}
      if (session->vep.next_sh != ~0)
	{
	  vcl_session_t *next_session;
	  next_session = vcl_session_get_w_handle (wrk, session->vep.next_sh);
	  if (PREDICT_FALSE (!next_session))
	    {
	      VDBG (0, "EPOLL_CTL_DEL: Invalid next_sh (%u) on sh (%u)!",
		    session->vep.next_sh, session_handle);
	      return VPPCOM_EBADFD;
	    }
	  ASSERT (next_session->vep.prev_sh == session_handle);
	  next_session->vep.prev_sh = session->vep.prev_sh;
	}

      memset (&session->vep, 0, sizeof (session->vep));
      session->vep.next_sh = ~0;
      session->vep.prev_sh = ~0;
      session->vep.vep_sh = ~0;
      session->is_vep_session = 0;

      if (session->tx_fifo)
	svm_fifo_del_want_deq_ntf (session->tx_fifo, SVM_FIFO_NO_DEQ_NOTIF);

      VDBG (1, "EPOLL_CTL_DEL: vep_idx %u, sh %u!", vep_handle,
	    session_handle);
      vcl_evt (VCL_EVT_EPOLL_CTLDEL, session, vep_sh);
      break;

    default:
      VDBG (0, "Invalid operation (%d)!", op);
      rv = VPPCOM_EINVAL;
    }

  vep_verify_epoll_chain (wrk, vep_handle);

done:
  return rv;
}

static inline void
vcl_epoll_wait_handle_mq_event (vcl_worker_t * wrk, session_event_t * e,
				struct epoll_event *events, u32 * num_ev)
{
  session_disconnected_msg_t *disconnected_msg;
  session_connected_msg_t *connected_msg;
  u32 sid = ~0, session_events;
  u64 session_evt_data = ~0;
  vcl_session_t *session;
  u8 add_event = 0;

  switch (e->event_type)
    {
    case SESSION_IO_EVT_RX:
      sid = e->session_index;
      if (!(session = vcl_session_get (wrk, sid)))
	break;
      vcl_fifo_rx_evt_valid_or_break (session);
      session_events = session->vep.ev.events;
      if (!(EPOLLIN & session->vep.ev.events) || session->has_rx_evt)
	break;
      add_event = 1;
      events[*num_ev].events |= EPOLLIN;
      session_evt_data = session->vep.ev.data.u64;
      session->has_rx_evt = 1;
      break;
    case SESSION_IO_EVT_TX:
      sid = e->session_index;
      if (!(session = vcl_session_get (wrk, sid)))
	break;
      session_events = session->vep.ev.events;
      if (!(EPOLLOUT & session_events))
	break;
      add_event = 1;
      events[*num_ev].events |= EPOLLOUT;
      session_evt_data = session->vep.ev.data.u64;
      svm_fifo_reset_has_deq_ntf (session->tx_fifo);
      break;
    case SESSION_CTRL_EVT_ACCEPTED:
      session = vcl_session_accepted (wrk,
				      (session_accepted_msg_t *) e->data);
      if (!session)
	break;

      session_events = session->vep.ev.events;
      if (!(EPOLLIN & session_events))
	break;

      add_event = 1;
      events[*num_ev].events |= EPOLLIN;
      session_evt_data = session->vep.ev.data.u64;
      break;
    case SESSION_CTRL_EVT_CONNECTED:
      connected_msg = (session_connected_msg_t *) e->data;
      vcl_session_connected_handler (wrk, connected_msg);
      /* Generate EPOLLOUT because there's no connected event */
      sid = vcl_session_index_from_vpp_handle (wrk, connected_msg->handle);
      if (!(session = vcl_session_get (wrk, sid)))
	break;
      session_events = session->vep.ev.events;
      if (!(EPOLLOUT & session_events))
	break;
      add_event = 1;
      events[*num_ev].events |= EPOLLOUT;
      session_evt_data = session->vep.ev.data.u64;
      break;
    case SESSION_CTRL_EVT_DISCONNECTED:
      disconnected_msg = (session_disconnected_msg_t *) e->data;
      session = vcl_session_disconnected_handler (wrk, disconnected_msg);
      if (!session)
	break;
      session_events = session->vep.ev.events;
      if (!((EPOLLHUP | EPOLLRDHUP) & session_events))
	break;
      add_event = 1;
      events[*num_ev].events |= EPOLLHUP | EPOLLRDHUP;
      session_evt_data = session->vep.ev.data.u64;
      break;
    case SESSION_CTRL_EVT_RESET:
      sid = vcl_session_reset_handler (wrk, (session_reset_msg_t *) e->data);
      if (!(session = vcl_session_get (wrk, sid)))
	break;
      session_events = session->vep.ev.events;
      if (!((EPOLLHUP | EPOLLRDHUP) & session_events))
	break;
      add_event = 1;
      events[*num_ev].events |= EPOLLHUP | EPOLLRDHUP;
      session_evt_data = session->vep.ev.data.u64;
      break;
    case SESSION_CTRL_EVT_UNLISTEN_REPLY:
      vcl_session_unlisten_reply_handler (wrk, e->data);
      break;
    case SESSION_CTRL_EVT_REQ_WORKER_UPDATE:
      vcl_session_req_worker_update_handler (wrk, e->data);
      break;
    case SESSION_CTRL_EVT_WORKER_UPDATE_REPLY:
      vcl_session_worker_update_reply_handler (wrk, e->data);
      break;
    default:
      VDBG (0, "unhandled: %u", e->event_type);
      break;
    }

  if (add_event)
    {
      events[*num_ev].data.u64 = session_evt_data;
      if (EPOLLONESHOT & session_events)
	{
	  session = vcl_session_get (wrk, sid);
	  session->vep.ev.events = 0;
	}
      *num_ev += 1;
    }
}

static int
vcl_epoll_wait_handle_mq (vcl_worker_t * wrk, svm_msg_q_t * mq,
			  struct epoll_event *events, u32 maxevents,
			  double wait_for_time, u32 * num_ev)
{
  svm_msg_q_msg_t *msg;
  session_event_t *e;
  int i;

  if (vec_len (wrk->mq_msg_vector) && svm_msg_q_is_empty (mq))
    goto handle_dequeued;

  svm_msg_q_lock (mq);
  if (svm_msg_q_is_empty (mq))
    {
      if (!wait_for_time)
	{
	  svm_msg_q_unlock (mq);
	  return 0;
	}
      else if (wait_for_time < 0)
	{
	  svm_msg_q_wait (mq);
	}
      else
	{
	  if (svm_msg_q_timedwait (mq, wait_for_time / 1e3))
	    {
	      svm_msg_q_unlock (mq);
	      return 0;
	    }
	}
    }
  ASSERT (maxevents > *num_ev);
  vcl_mq_dequeue_batch (wrk, mq, maxevents - *num_ev);
  svm_msg_q_unlock (mq);

handle_dequeued:
  for (i = 0; i < vec_len (wrk->mq_msg_vector); i++)
    {
      msg = vec_elt_at_index (wrk->mq_msg_vector, i);
      e = svm_msg_q_msg_data (mq, msg);
      vcl_epoll_wait_handle_mq_event (wrk, e, events, num_ev);
      svm_msg_q_free_msg (mq, msg);
    }
  vec_reset_length (wrk->mq_msg_vector);
  vcl_handle_pending_wrk_updates (wrk);
  return *num_ev;
}

static int
vppcom_epoll_wait_condvar (vcl_worker_t * wrk, struct epoll_event *events,
			   int maxevents, u32 n_evts, double wait_for_time)
{
  double wait = 0, start = 0, now;

  if (!n_evts)
    {
      wait = wait_for_time;
      start = clib_time_now (&wrk->clib_time);
    }

  do
    {
      vcl_epoll_wait_handle_mq (wrk, wrk->app_event_queue, events, maxevents,
				wait, &n_evts);
      if (n_evts)
	return n_evts;
      if (wait == -1)
	continue;

      now = clib_time_now (&wrk->clib_time);
      wait -= now - start;
      start = now;
    }
  while (wait > 0);

  return 0;
}

static int
vppcom_epoll_wait_eventfd (vcl_worker_t * wrk, struct epoll_event *events,
			   int maxevents, u32 n_evts, double wait_for_time)
{
  vcl_mq_evt_conn_t *mqc;
  int __clib_unused n_read;
  int n_mq_evts, i;
  u64 buf;

  vec_validate (wrk->mq_events, pool_elts (wrk->mq_evt_conns));
again:
  n_mq_evts = epoll_wait (wrk->mqs_epfd, wrk->mq_events,
			  vec_len (wrk->mq_events), wait_for_time);
  for (i = 0; i < n_mq_evts; i++)
    {
      mqc = vcl_mq_evt_conn_get (wrk, wrk->mq_events[i].data.u32);
      n_read = read (mqc->mq_fd, &buf, sizeof (buf));
      vcl_epoll_wait_handle_mq (wrk, mqc->mq, events, maxevents, 0, &n_evts);
    }
  if (!n_evts && n_mq_evts > 0)
    goto again;

  return (int) n_evts;
}

int
vppcom_epoll_wait (uint32_t vep_handle, struct epoll_event *events,
		   int maxevents, double wait_for_time)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *vep_session;
  u32 n_evts = 0;
  int i;

  if (PREDICT_FALSE (maxevents <= 0))
    {
      VDBG (0, "ERROR: Invalid maxevents (%d)!", maxevents);
      return VPPCOM_EINVAL;
    }

  vep_session = vcl_session_get_w_handle (wrk, vep_handle);
  if (!vep_session)
    return VPPCOM_EBADFD;

  if (PREDICT_FALSE (!vep_session->is_vep))
    {
      VDBG (0, "ERROR: vep_idx (%u) is not a vep!", vep_handle);
      return VPPCOM_EINVAL;
    }

  memset (events, 0, sizeof (*events) * maxevents);

  if (vec_len (wrk->unhandled_evts_vector))
    {
      for (i = 0; i < vec_len (wrk->unhandled_evts_vector); i++)
	{
	  vcl_epoll_wait_handle_mq_event (wrk, &wrk->unhandled_evts_vector[i],
					  events, &n_evts);
	  if (n_evts == maxevents)
	    {
	      vec_delete (wrk->unhandled_evts_vector, i + 1, 0);
	      return n_evts;
	    }
	}
      vec_reset_length (wrk->unhandled_evts_vector);
    }

  if (vcm->cfg.use_mq_eventfd)
    return vppcom_epoll_wait_eventfd (wrk, events, maxevents, n_evts,
				      wait_for_time);

  return vppcom_epoll_wait_condvar (wrk, events, maxevents, n_evts,
				    wait_for_time);
}

int
vppcom_session_attr (uint32_t session_handle, uint32_t op,
		     void *buffer, uint32_t * buflen)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  vcl_session_t *session;
  int rv = VPPCOM_OK;
  u32 *flags = buffer, tmp_flags = 0;
  vppcom_endpt_t *ep = buffer;

  session = vcl_session_get_w_handle (wrk, session_handle);
  if (!session)
    return VPPCOM_EBADFD;

  switch (op)
    {
    case VPPCOM_ATTR_GET_NREAD:
      rv = vcl_session_read_ready (session);
      VDBG (2, "VPPCOM_ATTR_GET_NREAD: sh %u, nread = %d", session_handle,
	    rv);
      break;

    case VPPCOM_ATTR_GET_NWRITE:
      rv = vcl_session_write_ready (session);
      VDBG (2, "VPPCOM_ATTR_GET_NWRITE: sh %u, nwrite = %d", session_handle,
	    rv);
      break;

    case VPPCOM_ATTR_GET_FLAGS:
      if (PREDICT_TRUE (buffer && buflen && (*buflen >= sizeof (*flags))))
	{
	  *flags = O_RDWR | (VCL_SESS_ATTR_TEST (session->attr,
						 VCL_SESS_ATTR_NONBLOCK));
	  *buflen = sizeof (*flags);
	  VDBG (2, "VPPCOM_ATTR_GET_FLAGS: sh %u, flags = 0x%08x, "
		"is_nonblocking = %u", session_handle, *flags,
		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_NONBLOCK));
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_FLAGS:
      if (PREDICT_TRUE (buffer && buflen && (*buflen == sizeof (*flags))))
	{
	  if (*flags & O_NONBLOCK)
	    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_NONBLOCK);
	  else
	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_NONBLOCK);

	  VDBG (2, "VPPCOM_ATTR_SET_FLAGS: sh %u, flags = 0x%08x,"
		" is_nonblocking = %u", session_handle, *flags,
		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_NONBLOCK));
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_PEER_ADDR:
      if (PREDICT_TRUE (buffer && buflen &&
			(*buflen >= sizeof (*ep)) && ep->ip))
	{
	  ep->is_ip4 = session->transport.is_ip4;
	  ep->port = session->transport.rmt_port;
	  if (session->transport.is_ip4)
	    clib_memcpy_fast (ep->ip, &session->transport.rmt_ip.ip4,
			      sizeof (ip4_address_t));
	  else
	    clib_memcpy_fast (ep->ip, &session->transport.rmt_ip.ip6,
			      sizeof (ip6_address_t));
	  *buflen = sizeof (*ep);
	  VDBG (1, "VPPCOM_ATTR_GET_PEER_ADDR: sh %u, is_ip4 = %u, "
		"addr = %U, port %u", session_handle, ep->is_ip4,
		format_ip46_address, &session->transport.rmt_ip,
		ep->is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
		clib_net_to_host_u16 (ep->port));
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_LCL_ADDR:
      if (PREDICT_TRUE (buffer && buflen &&
			(*buflen >= sizeof (*ep)) && ep->ip))
	{
	  ep->is_ip4 = session->transport.is_ip4;
	  ep->port = session->transport.lcl_port;
	  if (session->transport.is_ip4)
	    clib_memcpy_fast (ep->ip, &session->transport.lcl_ip.ip4,
			      sizeof (ip4_address_t));
	  else
	    clib_memcpy_fast (ep->ip, &session->transport.lcl_ip.ip6,
			      sizeof (ip6_address_t));
	  *buflen = sizeof (*ep);
	  VDBG (1, "VPPCOM_ATTR_GET_LCL_ADDR: sh %u, is_ip4 = %u, addr = %U"
		" port %d", session_handle, ep->is_ip4, format_ip46_address,
		&session->transport.lcl_ip,
		ep->is_ip4 ? IP46_TYPE_IP4 : IP46_TYPE_IP6,
		clib_net_to_host_u16 (ep->port));
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_LIBC_EPFD:
      rv = session->libc_epfd;
      VDBG (2, "VPPCOM_ATTR_GET_LIBC_EPFD: libc_epfd %d", rv);
      break;

    case VPPCOM_ATTR_SET_LIBC_EPFD:
      if (PREDICT_TRUE (buffer && buflen &&
			(*buflen == sizeof (session->libc_epfd))))
	{
	  session->libc_epfd = *(int *) buffer;
	  *buflen = sizeof (session->libc_epfd);

	  VDBG (2, "VPPCOM_ATTR_SET_LIBC_EPFD: libc_epfd %d, buflen %d",
		session->libc_epfd, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_PROTOCOL:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  *(int *) buffer = session->session_type;
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_PROTOCOL: %d (%s), buflen %d",
		*(int *) buffer, *(int *) buffer ? "UDP" : "TCP", *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_LISTEN:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  *(int *) buffer = VCL_SESS_ATTR_TEST (session->attr,
						VCL_SESS_ATTR_LISTEN);
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_LISTEN: %d, buflen %d", *(int *) buffer,
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_ERROR:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  *(int *) buffer = 0;
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_ERROR: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_TX_FIFO_LEN:
      if (buffer && buflen && (*buflen >= sizeof (u32)))
	{

	  /* VPP-TBD */
	  *(size_t *) buffer = (session->sndbuf_size ? session->sndbuf_size :
				session->tx_fifo ? session->tx_fifo->nitems :
				vcm->cfg.tx_fifo_size);
	  *buflen = sizeof (u32);

	  VDBG (2, "VPPCOM_ATTR_GET_TX_FIFO_LEN: %u (0x%x), buflen %d,"
		" #VPP-TBD#", *(size_t *) buffer, *(size_t *) buffer,
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_TX_FIFO_LEN:
      if (buffer && buflen && (*buflen == sizeof (u32)))
	{
	  /* VPP-TBD */
	  session->sndbuf_size = *(u32 *) buffer;
	  VDBG (2, "VPPCOM_ATTR_SET_TX_FIFO_LEN: %u (0x%x), buflen %d,"
		" #VPP-TBD#", session->sndbuf_size, session->sndbuf_size,
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_RX_FIFO_LEN:
      if (buffer && buflen && (*buflen >= sizeof (u32)))
	{

	  /* VPP-TBD */
	  *(size_t *) buffer = (session->rcvbuf_size ? session->rcvbuf_size :
				session->rx_fifo ? session->rx_fifo->nitems :
				vcm->cfg.rx_fifo_size);
	  *buflen = sizeof (u32);

	  VDBG (2, "VPPCOM_ATTR_GET_RX_FIFO_LEN: %u (0x%x), buflen %d, "
		"#VPP-TBD#", *(size_t *) buffer, *(size_t *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_RX_FIFO_LEN:
      if (buffer && buflen && (*buflen == sizeof (u32)))
	{
	  /* VPP-TBD */
	  session->rcvbuf_size = *(u32 *) buffer;
	  VDBG (2, "VPPCOM_ATTR_SET_RX_FIFO_LEN: %u (0x%x), buflen %d,"
		" #VPP-TBD#", session->sndbuf_size, session->sndbuf_size,
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_REUSEADDR:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  /* VPP-TBD */
	  *(int *) buffer = VCL_SESS_ATTR_TEST (session->attr,
						VCL_SESS_ATTR_REUSEADDR);
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_REUSEADDR: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_REUSEADDR:
      if (buffer && buflen && (*buflen == sizeof (int)) &&
	  !VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_LISTEN))
	{
	  /* VPP-TBD */
	  if (*(int *) buffer)
	    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_REUSEADDR);
	  else
	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_REUSEADDR);

	  VDBG (2, "VPPCOM_ATTR_SET_REUSEADDR: %d, buflen %d, #VPP-TBD#",
		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_REUSEADDR),
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_REUSEPORT:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  /* VPP-TBD */
	  *(int *) buffer = VCL_SESS_ATTR_TEST (session->attr,
						VCL_SESS_ATTR_REUSEPORT);
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_REUSEPORT: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_REUSEPORT:
      if (buffer && buflen && (*buflen == sizeof (int)) &&
	  !VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_LISTEN))
	{
	  /* VPP-TBD */
	  if (*(int *) buffer)
	    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_REUSEPORT);
	  else
	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_REUSEPORT);

	  VDBG (2, "VPPCOM_ATTR_SET_REUSEPORT: %d, buflen %d, #VPP-TBD#",
		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_REUSEPORT),
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_BROADCAST:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  /* VPP-TBD */
	  *(int *) buffer = VCL_SESS_ATTR_TEST (session->attr,
						VCL_SESS_ATTR_BROADCAST);
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_BROADCAST: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_BROADCAST:
      if (buffer && buflen && (*buflen == sizeof (int)))
	{
	  /* VPP-TBD */
	  if (*(int *) buffer)
	    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_BROADCAST);
	  else
	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_BROADCAST);

	  VDBG (2, "VPPCOM_ATTR_SET_BROADCAST: %d, buflen %d, #VPP-TBD#",
		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_BROADCAST),
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_V6ONLY:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  /* VPP-TBD */
	  *(int *) buffer = VCL_SESS_ATTR_TEST (session->attr,
						VCL_SESS_ATTR_V6ONLY);
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_V6ONLY: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_V6ONLY:
      if (buffer && buflen && (*buflen == sizeof (int)))
	{
	  /* VPP-TBD */
	  if (*(int *) buffer)
	    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_V6ONLY);
	  else
	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_V6ONLY);

	  VDBG (2, "VPPCOM_ATTR_SET_V6ONLY: %d, buflen %d, #VPP-TBD#",
		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_V6ONLY),
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_KEEPALIVE:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  /* VPP-TBD */
	  *(int *) buffer = VCL_SESS_ATTR_TEST (session->attr,
						VCL_SESS_ATTR_KEEPALIVE);
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_KEEPALIVE: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_KEEPALIVE:
      if (buffer && buflen && (*buflen == sizeof (int)))
	{
	  /* VPP-TBD */
	  if (*(int *) buffer)
	    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_KEEPALIVE);
	  else
	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_KEEPALIVE);

	  VDBG (2, "VPPCOM_ATTR_SET_KEEPALIVE: %d, buflen %d, #VPP-TBD#",
		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_KEEPALIVE),
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_TCP_NODELAY:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  /* VPP-TBD */
	  *(int *) buffer = VCL_SESS_ATTR_TEST (session->attr,
						VCL_SESS_ATTR_TCP_NODELAY);
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_TCP_NODELAY: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_TCP_NODELAY:
      if (buffer && buflen && (*buflen == sizeof (int)))
	{
	  /* VPP-TBD */
	  if (*(int *) buffer)
	    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_TCP_NODELAY);
	  else
	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_TCP_NODELAY);

	  VDBG (2, "VPPCOM_ATTR_SET_TCP_NODELAY: %d, buflen %d, #VPP-TBD#",
		VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_TCP_NODELAY),
		*buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_TCP_KEEPIDLE:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  /* VPP-TBD */
	  *(int *) buffer = VCL_SESS_ATTR_TEST (session->attr,
						VCL_SESS_ATTR_TCP_KEEPIDLE);
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_TCP_KEEPIDLE: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_TCP_KEEPIDLE:
      if (buffer && buflen && (*buflen == sizeof (int)))
	{
	  /* VPP-TBD */
	  if (*(int *) buffer)
	    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_TCP_KEEPIDLE);
	  else
	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_TCP_KEEPIDLE);

	  VDBG (2, "VPPCOM_ATTR_SET_TCP_KEEPIDLE: %d, buflen %d, #VPP-TBD#",
		VCL_SESS_ATTR_TEST (session->attr,
				    VCL_SESS_ATTR_TCP_KEEPIDLE), *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_TCP_KEEPINTVL:
      if (buffer && buflen && (*buflen >= sizeof (int)))
	{
	  /* VPP-TBD */
	  *(int *) buffer = VCL_SESS_ATTR_TEST (session->attr,
						VCL_SESS_ATTR_TCP_KEEPINTVL);
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_TCP_KEEPINTVL: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_TCP_KEEPINTVL:
      if (buffer && buflen && (*buflen == sizeof (int)))
	{
	  /* VPP-TBD */
	  if (*(int *) buffer)
	    VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_TCP_KEEPINTVL);
	  else
	    VCL_SESS_ATTR_CLR (session->attr, VCL_SESS_ATTR_TCP_KEEPINTVL);

	  VDBG (2, "VPPCOM_ATTR_SET_TCP_KEEPINTVL: %d, buflen %d, #VPP-TBD#",
		VCL_SESS_ATTR_TEST (session->attr,
				    VCL_SESS_ATTR_TCP_KEEPINTVL), *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_GET_TCP_USER_MSS:
      if (buffer && buflen && (*buflen >= sizeof (u32)))
	{
	  /* VPP-TBD */
	  *(u32 *) buffer = session->user_mss;
	  *buflen = sizeof (int);

	  VDBG (2, "VPPCOM_ATTR_GET_TCP_USER_MSS: %d, buflen %d, #VPP-TBD#",
		*(int *) buffer, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_TCP_USER_MSS:
      if (buffer && buflen && (*buflen == sizeof (u32)))
	{
	  /* VPP-TBD */
	  session->user_mss = *(u32 *) buffer;

	  VDBG (2, "VPPCOM_ATTR_SET_TCP_USER_MSS: %u, buflen %d, #VPP-TBD#",
		session->user_mss, *buflen);
	}
      else
	rv = VPPCOM_EINVAL;
      break;

    case VPPCOM_ATTR_SET_SHUT:
      if (*flags == SHUT_RD || *flags == SHUT_RDWR)
	VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_SHUT_RD);
      if (*flags == SHUT_WR || *flags == SHUT_RDWR)
	VCL_SESS_ATTR_SET (session->attr, VCL_SESS_ATTR_SHUT_WR);
      break;

    case VPPCOM_ATTR_GET_SHUT:
      if (VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_SHUT_RD))
	tmp_flags = 1;
      if (VCL_SESS_ATTR_TEST (session->attr, VCL_SESS_ATTR_SHUT_WR))
	tmp_flags |= 2;
      if (tmp_flags == 1)
	*(int *) buffer = SHUT_RD;
      else if (tmp_flags == 2)
	*(int *) buffer = SHUT_WR;
      else if (tmp_flags == 3)
	*(int *) buffer = SHUT_RDWR;
      *buflen = sizeof (int);
      break;
    default:
      rv = VPPCOM_EINVAL;
      break;
    }

  return rv;
}

int
vppcom_session_recvfrom (uint32_t session_handle, void *buffer,
			 uint32_t buflen, int flags, vppcom_endpt_t * ep)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  int rv = VPPCOM_OK;
  vcl_session_t *session = 0;

  if (ep)
    {
      session = vcl_session_get_w_handle (wrk, session_handle);
      if (PREDICT_FALSE (!session))
	{
	  VDBG (0, "sh 0x%llx is closed!", session_handle);
	  return VPPCOM_EBADFD;
	}
      ep->is_ip4 = session->transport.is_ip4;
      ep->port = session->transport.rmt_port;
    }

  if (flags == 0)
    rv = vppcom_session_read (session_handle, buffer, buflen);
  else if (flags & MSG_PEEK)
    rv = vppcom_session_peek (session_handle, buffer, buflen);
  else
    {
      VDBG (0, "Unsupport flags for recvfrom %d", flags);
      return VPPCOM_EAFNOSUPPORT;
    }

  if (ep)
    {
      if (session->transport.is_ip4)
	clib_memcpy_fast (ep->ip, &session->transport.rmt_ip.ip4,
			  sizeof (ip4_address_t));
      else
	clib_memcpy_fast (ep->ip, &session->transport.rmt_ip.ip6,
			  sizeof (ip6_address_t));
    }

  return rv;
}

int
vppcom_session_sendto (uint32_t session_handle, void *buffer,
		       uint32_t buflen, int flags, vppcom_endpt_t * ep)
{
  if (!buffer)
    return VPPCOM_EINVAL;

  if (ep)
    {
      // TBD
      return VPPCOM_EINVAL;
    }

  if (flags)
    {
      // TBD check the flags and do the right thing
      VDBG (2, "handling flags 0x%u (%d) not implemented yet.", flags, flags);
    }

  return (vppcom_session_write_inline (session_handle, buffer, buflen, 1));
}

int
vppcom_poll (vcl_poll_t * vp, uint32_t n_sids, double wait_for_time)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  f64 timeout = clib_time_now (&wrk->clib_time) + wait_for_time;
  u32 i, keep_trying = 1;
  svm_msg_q_msg_t msg;
  session_event_t *e;
  int rv, num_ev = 0;

  VDBG (3, "vp %p, nsids %u, wait_for_time %f", vp, n_sids, wait_for_time);

  if (!vp)
    return VPPCOM_EFAULT;

  do
    {
      vcl_session_t *session;

      /* Dequeue all events and drop all unhandled io events */
      while (svm_msg_q_sub (wrk->app_event_queue, &msg, SVM_Q_NOWAIT, 0) == 0)
	{
	  e = svm_msg_q_msg_data (wrk->app_event_queue, &msg);
	  vcl_handle_mq_event (wrk, e);
	  svm_msg_q_free_msg (wrk->app_event_queue, &msg);
	}
      vec_reset_length (wrk->unhandled_evts_vector);

      for (i = 0; i < n_sids; i++)
	{
	  session = vcl_session_get (wrk, vp[i].sh);
	  if (!session)
	    {
	      vp[i].revents = POLLHUP;
	      num_ev++;
	      continue;
	    }

	  vp[i].revents = 0;

	  if (POLLIN & vp[i].events)
	    {
	      rv = vcl_session_read_ready (session);
	      if (rv > 0)
		{
		  vp[i].revents |= POLLIN;
		  num_ev++;
		}
	      else if (rv < 0)
		{
		  switch (rv)
		    {
		    case VPPCOM_ECONNRESET:
		      vp[i].revents = POLLHUP;
		      break;

		    default:
		      vp[i].revents = POLLERR;
		      break;
		    }
		  num_ev++;
		}
	    }

	  if (POLLOUT & vp[i].events)
	    {
	      rv = vcl_session_write_ready (session);
	      if (rv > 0)
		{
		  vp[i].revents |= POLLOUT;
		  num_ev++;
		}
	      else if (rv < 0)
		{
		  switch (rv)
		    {
		    case VPPCOM_ECONNRESET:
		      vp[i].revents = POLLHUP;
		      break;

		    default:
		      vp[i].revents = POLLERR;
		      break;
		    }
		  num_ev++;
		}
	    }

	  if (0)		// Note "done:" label used by VCL_SESSION_LOCK_AND_GET()
	    {
	      vp[i].revents = POLLNVAL;
	      num_ev++;
	    }
	}
      if (wait_for_time != -1)
	keep_trying = (clib_time_now (&wrk->clib_time) <= timeout) ? 1 : 0;
    }
  while ((num_ev == 0) && keep_trying);

  return num_ev;
}

int
vppcom_mq_epoll_fd (void)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  return wrk->mqs_epfd;
}

int
vppcom_session_index (vcl_session_handle_t session_handle)
{
  return session_handle & 0xFFFFFF;
}

int
vppcom_session_worker (vcl_session_handle_t session_handle)
{
  return session_handle >> 24;
}

int
vppcom_worker_register (void)
{
  if (!vcl_worker_alloc_and_init ())
    return VPPCOM_EEXIST;

  if (vcl_worker_set_bapi ())
    return VPPCOM_EEXIST;

  if (vcl_worker_register_with_vpp ())
    return VPPCOM_EEXIST;

  return VPPCOM_OK;
}

int
vppcom_worker_index (void)
{
  return vcl_get_worker_index ();
}

int
vppcom_worker_mqs_epfd (void)
{
  vcl_worker_t *wrk = vcl_worker_get_current ();
  if (!vcm->cfg.use_mq_eventfd)
    return -1;
  return wrk->mqs_epfd;
}

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */