xref: /aosp_15_r20/external/grpc-grpc/test/core/util/port_isolated_runtime_environment.cc (revision cc02d7e222339f7a4f6ba5f422e6413f4bd931f2)
1 //
2 //
3 // Copyright 2017 gRPC authors.
4 //
5 // Licensed under the Apache License, Version 2.0 (the "License");
6 // you may not use this file except in compliance with the License.
7 // You may obtain a copy of the License at
8 //
9 //     http://www.apache.org/licenses/LICENSE-2.0
10 //
11 // Unless required by applicable law or agreed to in writing, software
12 // distributed under the License is distributed on an "AS IS" BASIS,
13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 // See the License for the specific language governing permissions and
15 // limitations under the License.
16 //
17 //
18 
19 #if defined(GRPC_PORT_ISOLATED_RUNTIME)
20 
21 // When individual tests run in an isolated runtime environment (e.g. each test
22 // runs in a separate container) the framework takes a round-robin pick of a
23 // port within certain range. There is no need to recycle ports.
24 //
25 #include <stdlib.h>
26 
27 #include <grpc/support/atm.h>
28 #include <grpc/support/log.h>
29 #include <grpc/support/time.h>
30 
31 #include "src/core/lib/gprpp/crash.h"
32 #include "src/core/lib/iomgr/port.h"
33 #include "test/core/util/port.h"
34 #include "test/core/util/test_config.h"
35 
36 #define MIN_PORT 1025
37 #define MAX_PORT 32766
38 
get_random_port_offset()39 static int get_random_port_offset() {
40   srand(gpr_now(GPR_CLOCK_REALTIME).tv_nsec);
41   double rnd = static_cast<double>(rand()) /
42                (static_cast<double>(RAND_MAX) + 1.0);  // values from [0,1)
43   return static_cast<int>(rnd * (MAX_PORT - MIN_PORT + 1));
44 }
45 
46 static int s_initial_offset = get_random_port_offset();
47 static gpr_atm s_pick_counter = 0;
48 
grpc_pick_unused_port_or_die_impl(void)49 static int grpc_pick_unused_port_or_die_impl(void) {
50   int orig_counter_val =
51       static_cast<int>(gpr_atm_full_fetch_add(&s_pick_counter, 1));
52   GPR_ASSERT(orig_counter_val < (MAX_PORT - MIN_PORT + 1));
53   return MIN_PORT +
54          (s_initial_offset + orig_counter_val) % (MAX_PORT - MIN_PORT + 1);
55 }
56 
isolated_pick_unused_port_or_die(void)57 static int isolated_pick_unused_port_or_die(void) {
58   while (true) {
59     int port = grpc_pick_unused_port_or_die_impl();
60     // 5985 cannot be bound on Windows RBE and results in
61     // WSA_ERROR 10013: "An attempt was made to access a socket in a way
62     // forbidden by its access permissions."
63     if (port == 5985) {
64       continue;
65     }
66     return port;
67   }
68 }
69 
isolated_recycle_unused_port(int port)70 static void isolated_recycle_unused_port(int port) { (void)port; }
71 
72 // We don't actually use prev_fns for anything, but need to save it in order to
73 // be able to call grpc_set_pick_port_functions() to override defaults for this
74 // environment.
75 static const auto prev_fns =
76     grpc_set_pick_port_functions(grpc_pick_port_functions{
77         isolated_pick_unused_port_or_die, isolated_recycle_unused_port});
78 
79 #endif  // GRPC_PORT_ISOLATED_RUNTIME
80