1 /*
2 *
3 * Copyright 2015 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 #include <grpc/support/port_platform.h>
20
21 #include "src/core/lib/iomgr/port.h"
22
23 #ifdef GRPC_POSIX_SOCKET_UTILS_COMMON
24
25 #include "src/core/lib/iomgr/socket_utils.h"
26 #include "src/core/lib/iomgr/socket_utils_posix.h"
27
28 #include <arpa/inet.h>
29 #include <errno.h>
30 #include <fcntl.h>
31 #include <limits.h>
32 #include <netinet/in.h>
33 #ifdef GRPC_LINUX_TCP_H
34 #include <linux/tcp.h>
35 #else
36 #include <netinet/tcp.h>
37 #endif
38 #include <stdio.h>
39 #include <string.h>
40 #include <sys/socket.h>
41 #include <sys/types.h>
42 #include <unistd.h>
43
44 #include <string>
45
46 #include <grpc/support/alloc.h>
47 #include <grpc/support/log.h>
48 #include <grpc/support/sync.h>
49
50 #include "src/core/lib/channel/channel_args.h"
51 #include "src/core/lib/gpr/string.h"
52 #include "src/core/lib/iomgr/sockaddr.h"
53 #include "src/core/lib/iomgr/sockaddr_utils.h"
54
55 /* set a socket to use zerocopy */
grpc_set_socket_zerocopy(int fd)56 grpc_error* grpc_set_socket_zerocopy(int fd) {
57 #ifdef GRPC_LINUX_ERRQUEUE
58 const int enable = 1;
59 auto err = setsockopt(fd, SOL_SOCKET, SO_ZEROCOPY, &enable, sizeof(enable));
60 if (err != 0) {
61 return GRPC_OS_ERROR(errno, "setsockopt(SO_ZEROCOPY)");
62 }
63 return GRPC_ERROR_NONE;
64 #else
65 (void)fd;
66 return GRPC_OS_ERROR(ENOSYS, "setsockopt(SO_ZEROCOPY)");
67 #endif
68 }
69
70 /* set a socket to non blocking mode */
grpc_set_socket_nonblocking(int fd,int non_blocking)71 grpc_error* grpc_set_socket_nonblocking(int fd, int non_blocking) {
72 int oldflags = fcntl(fd, F_GETFL, 0);
73 if (oldflags < 0) {
74 return GRPC_OS_ERROR(errno, "fcntl");
75 }
76
77 if (non_blocking) {
78 oldflags |= O_NONBLOCK;
79 } else {
80 oldflags &= ~O_NONBLOCK;
81 }
82
83 if (fcntl(fd, F_SETFL, oldflags) != 0) {
84 return GRPC_OS_ERROR(errno, "fcntl");
85 }
86
87 return GRPC_ERROR_NONE;
88 }
89
grpc_set_socket_no_sigpipe_if_possible(int fd)90 grpc_error* grpc_set_socket_no_sigpipe_if_possible(int fd) {
91 #ifdef GRPC_HAVE_SO_NOSIGPIPE
92 int val = 1;
93 int newval;
94 socklen_t intlen = sizeof(newval);
95 if (0 != setsockopt(fd, SOL_SOCKET, SO_NOSIGPIPE, &val, sizeof(val))) {
96 return GRPC_OS_ERROR(errno, "setsockopt(SO_NOSIGPIPE)");
97 }
98 if (0 != getsockopt(fd, SOL_SOCKET, SO_NOSIGPIPE, &newval, &intlen)) {
99 return GRPC_OS_ERROR(errno, "getsockopt(SO_NOSIGPIPE)");
100 }
101 if ((newval != 0) != (val != 0)) {
102 return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to set SO_NOSIGPIPE");
103 }
104 #else
105 // Avoid unused parameter warning for conditional parameter
106 (void)fd;
107 #endif
108 return GRPC_ERROR_NONE;
109 }
110
grpc_set_socket_ip_pktinfo_if_possible(int fd)111 grpc_error* grpc_set_socket_ip_pktinfo_if_possible(int fd) {
112 // Use conditionally-important parameter to avoid warning
113 (void)fd;
114 #ifdef GRPC_HAVE_IP_PKTINFO
115 int get_local_ip = 1;
116 if (0 != setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &get_local_ip,
117 sizeof(get_local_ip))) {
118 return GRPC_OS_ERROR(errno, "setsockopt(IP_PKTINFO)");
119 }
120 #endif
121 return GRPC_ERROR_NONE;
122 }
123
grpc_set_socket_ipv6_recvpktinfo_if_possible(int fd)124 grpc_error* grpc_set_socket_ipv6_recvpktinfo_if_possible(int fd) {
125 // Use conditionally-important parameter to avoid warning
126 (void)fd;
127 #ifdef GRPC_HAVE_IPV6_RECVPKTINFO
128 int get_local_ip = 1;
129 if (0 != setsockopt(fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &get_local_ip,
130 sizeof(get_local_ip))) {
131 return GRPC_OS_ERROR(errno, "setsockopt(IPV6_RECVPKTINFO)");
132 }
133 #endif
134 return GRPC_ERROR_NONE;
135 }
136
grpc_set_socket_sndbuf(int fd,int buffer_size_bytes)137 grpc_error* grpc_set_socket_sndbuf(int fd, int buffer_size_bytes) {
138 return 0 == setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &buffer_size_bytes,
139 sizeof(buffer_size_bytes))
140 ? GRPC_ERROR_NONE
141 : GRPC_OS_ERROR(errno, "setsockopt(SO_SNDBUF)");
142 }
143
grpc_set_socket_rcvbuf(int fd,int buffer_size_bytes)144 grpc_error* grpc_set_socket_rcvbuf(int fd, int buffer_size_bytes) {
145 return 0 == setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &buffer_size_bytes,
146 sizeof(buffer_size_bytes))
147 ? GRPC_ERROR_NONE
148 : GRPC_OS_ERROR(errno, "setsockopt(SO_RCVBUF)");
149 }
150
151 /* set a socket to close on exec */
grpc_set_socket_cloexec(int fd,int close_on_exec)152 grpc_error* grpc_set_socket_cloexec(int fd, int close_on_exec) {
153 int oldflags = fcntl(fd, F_GETFD, 0);
154 if (oldflags < 0) {
155 return GRPC_OS_ERROR(errno, "fcntl");
156 }
157
158 if (close_on_exec) {
159 oldflags |= FD_CLOEXEC;
160 } else {
161 oldflags &= ~FD_CLOEXEC;
162 }
163
164 if (fcntl(fd, F_SETFD, oldflags) != 0) {
165 return GRPC_OS_ERROR(errno, "fcntl");
166 }
167
168 return GRPC_ERROR_NONE;
169 }
170
171 /* set a socket to reuse old addresses */
grpc_set_socket_reuse_addr(int fd,int reuse)172 grpc_error* grpc_set_socket_reuse_addr(int fd, int reuse) {
173 int val = (reuse != 0);
174 int newval;
175 socklen_t intlen = sizeof(newval);
176 if (0 != setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val))) {
177 return GRPC_OS_ERROR(errno, "setsockopt(SO_REUSEADDR)");
178 }
179 if (0 != getsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &newval, &intlen)) {
180 return GRPC_OS_ERROR(errno, "getsockopt(SO_REUSEADDR)");
181 }
182 if ((newval != 0) != val) {
183 return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to set SO_REUSEADDR");
184 }
185
186 return GRPC_ERROR_NONE;
187 }
188
189 /* set a socket to reuse old addresses */
grpc_set_socket_reuse_port(int fd,int reuse)190 grpc_error* grpc_set_socket_reuse_port(int fd, int reuse) {
191 #ifndef SO_REUSEPORT
192 return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
193 "SO_REUSEPORT unavailable on compiling system");
194 #else
195 int val = (reuse != 0);
196 int newval;
197 socklen_t intlen = sizeof(newval);
198 if (0 != setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &val, sizeof(val))) {
199 return GRPC_OS_ERROR(errno, "setsockopt(SO_REUSEPORT)");
200 }
201 if (0 != getsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &newval, &intlen)) {
202 return GRPC_OS_ERROR(errno, "getsockopt(SO_REUSEPORT)");
203 }
204 if ((newval != 0) != val) {
205 return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to set SO_REUSEPORT");
206 }
207
208 return GRPC_ERROR_NONE;
209 #endif
210 }
211
212 static gpr_once g_probe_so_reuesport_once = GPR_ONCE_INIT;
213 static int g_support_so_reuseport = false;
214
probe_so_reuseport_once(void)215 void probe_so_reuseport_once(void) {
216 int s = socket(AF_INET, SOCK_STREAM, 0);
217 if (s < 0) {
218 /* This might be an ipv6-only environment in which case 'socket(AF_INET,..)'
219 call would fail. Try creating IPv6 socket in that case */
220 s = socket(AF_INET6, SOCK_STREAM, 0);
221 }
222 if (s >= 0) {
223 g_support_so_reuseport = GRPC_LOG_IF_ERROR(
224 "check for SO_REUSEPORT", grpc_set_socket_reuse_port(s, 1));
225 close(s);
226 }
227 }
228
grpc_is_socket_reuse_port_supported()229 bool grpc_is_socket_reuse_port_supported() {
230 gpr_once_init(&g_probe_so_reuesport_once, probe_so_reuseport_once);
231 return g_support_so_reuseport;
232 }
233
234 /* disable nagle */
grpc_set_socket_low_latency(int fd,int low_latency)235 grpc_error* grpc_set_socket_low_latency(int fd, int low_latency) {
236 int val = (low_latency != 0);
237 int newval;
238 socklen_t intlen = sizeof(newval);
239 if (0 != setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val))) {
240 return GRPC_OS_ERROR(errno, "setsockopt(TCP_NODELAY)");
241 }
242 if (0 != getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &newval, &intlen)) {
243 return GRPC_OS_ERROR(errno, "getsockopt(TCP_NODELAY)");
244 }
245 if ((newval != 0) != val) {
246 return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to set TCP_NODELAY");
247 }
248 return GRPC_ERROR_NONE;
249 }
250
251 /* The default values for TCP_USER_TIMEOUT are currently configured to be in
252 * line with the default values of KEEPALIVE_TIMEOUT as proposed in
253 * https://github.com/grpc/proposal/blob/master/A18-tcp-user-timeout.md */
254 #define DEFAULT_CLIENT_TCP_USER_TIMEOUT_MS 20000 /* 20 seconds */
255 #define DEFAULT_SERVER_TCP_USER_TIMEOUT_MS 20000 /* 20 seconds */
256
257 static int g_default_client_tcp_user_timeout_ms =
258 DEFAULT_CLIENT_TCP_USER_TIMEOUT_MS;
259 static int g_default_server_tcp_user_timeout_ms =
260 DEFAULT_SERVER_TCP_USER_TIMEOUT_MS;
261 static bool g_default_client_tcp_user_timeout_enabled = false;
262 static bool g_default_server_tcp_user_timeout_enabled = true;
263
264 #if GPR_LINUX == 1
265 // For Linux, it will be detected to support TCP_USER_TIMEOUT
266 #ifndef TCP_USER_TIMEOUT
267 #define TCP_USER_TIMEOUT 18
268 #endif
269 #define SOCKET_SUPPORTS_TCP_USER_TIMEOUT_DEFAULT 0
270 #else
271 // For non-Linux, TCP_USER_TIMEOUT will be used if TCP_USER_TIMEOUT is defined.
272 #ifdef TCP_USER_TIMEOUT
273 #define SOCKET_SUPPORTS_TCP_USER_TIMEOUT_DEFAULT 0
274 #else
275 #define TCP_USER_TIMEOUT 0
276 #define SOCKET_SUPPORTS_TCP_USER_TIMEOUT_DEFAULT -1
277 #endif // TCP_USER_TIMEOUT
278 #endif // GPR_LINUX == 1
279
280 // Whether the socket supports TCP_USER_TIMEOUT option.
281 // (0: don't know, 1: support, -1: not support)
282 static std::atomic<int> g_socket_supports_tcp_user_timeout(
283 SOCKET_SUPPORTS_TCP_USER_TIMEOUT_DEFAULT);
284
config_default_tcp_user_timeout(bool enable,int timeout,bool is_client)285 void config_default_tcp_user_timeout(bool enable, int timeout, bool is_client) {
286 if (is_client) {
287 g_default_client_tcp_user_timeout_enabled = enable;
288 if (timeout > 0) {
289 g_default_client_tcp_user_timeout_ms = timeout;
290 }
291 } else {
292 g_default_server_tcp_user_timeout_enabled = enable;
293 if (timeout > 0) {
294 g_default_server_tcp_user_timeout_ms = timeout;
295 }
296 }
297 }
298
299 /* Set TCP_USER_TIMEOUT */
grpc_set_socket_tcp_user_timeout(int fd,const grpc_channel_args * channel_args,bool is_client)300 grpc_error* grpc_set_socket_tcp_user_timeout(
301 int fd, const grpc_channel_args* channel_args, bool is_client) {
302 // Use conditionally-important parameter to avoid warning
303 (void)fd;
304 (void)channel_args;
305 (void)is_client;
306 extern grpc_core::TraceFlag grpc_tcp_trace;
307 if (g_socket_supports_tcp_user_timeout.load() >= 0) {
308 bool enable;
309 int timeout;
310 if (is_client) {
311 enable = g_default_client_tcp_user_timeout_enabled;
312 timeout = g_default_client_tcp_user_timeout_ms;
313 } else {
314 enable = g_default_server_tcp_user_timeout_enabled;
315 timeout = g_default_server_tcp_user_timeout_ms;
316 }
317 if (channel_args) {
318 for (unsigned int i = 0; i < channel_args->num_args; i++) {
319 if (0 ==
320 strcmp(channel_args->args[i].key, GRPC_ARG_KEEPALIVE_TIME_MS)) {
321 const int value = grpc_channel_arg_get_integer(
322 &channel_args->args[i], grpc_integer_options{0, 1, INT_MAX});
323 /* Continue using default if value is 0 */
324 if (value == 0) {
325 continue;
326 }
327 /* Disable if value is INT_MAX */
328 enable = value != INT_MAX;
329 } else if (0 == strcmp(channel_args->args[i].key,
330 GRPC_ARG_KEEPALIVE_TIMEOUT_MS)) {
331 const int value = grpc_channel_arg_get_integer(
332 &channel_args->args[i], grpc_integer_options{0, 1, INT_MAX});
333 /* Continue using default if value is 0 */
334 if (value == 0) {
335 continue;
336 }
337 timeout = value;
338 }
339 }
340 }
341 if (enable) {
342 int newval;
343 socklen_t len = sizeof(newval);
344 // If this is the first time to use TCP_USER_TIMEOUT, try to check
345 // if it is available.
346 if (g_socket_supports_tcp_user_timeout.load() == 0) {
347 if (0 != getsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &newval, &len)) {
348 gpr_log(GPR_INFO,
349 "TCP_USER_TIMEOUT is not available. TCP_USER_TIMEOUT won't "
350 "be used thereafter");
351 g_socket_supports_tcp_user_timeout.store(-1);
352 } else {
353 gpr_log(GPR_INFO,
354 "TCP_USER_TIMEOUT is available. TCP_USER_TIMEOUT will be "
355 "used thereafter");
356 g_socket_supports_tcp_user_timeout.store(1);
357 }
358 }
359 if (g_socket_supports_tcp_user_timeout.load() > 0) {
360 if (GRPC_TRACE_FLAG_ENABLED(grpc_tcp_trace)) {
361 gpr_log(GPR_INFO, "Enabling TCP_USER_TIMEOUT with a timeout of %d ms",
362 timeout);
363 }
364 if (0 != setsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &timeout,
365 sizeof(timeout))) {
366 gpr_log(GPR_ERROR, "setsockopt(TCP_USER_TIMEOUT) %s",
367 strerror(errno));
368 return GRPC_ERROR_NONE;
369 }
370 if (0 != getsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &newval, &len)) {
371 gpr_log(GPR_ERROR, "getsockopt(TCP_USER_TIMEOUT) %s",
372 strerror(errno));
373 return GRPC_ERROR_NONE;
374 }
375 if (newval != timeout) {
376 /* Do not fail on failing to set TCP_USER_TIMEOUT for now. */
377 gpr_log(GPR_ERROR, "Failed to set TCP_USER_TIMEOUT");
378 return GRPC_ERROR_NONE;
379 }
380 }
381 }
382 } else {
383 if (GRPC_TRACE_FLAG_ENABLED(grpc_tcp_trace)) {
384 gpr_log(GPR_INFO, "TCP_USER_TIMEOUT not supported for this platform");
385 }
386 }
387 return GRPC_ERROR_NONE;
388 }
389
390 /* set a socket using a grpc_socket_mutator */
grpc_set_socket_with_mutator(int fd,grpc_socket_mutator * mutator)391 grpc_error* grpc_set_socket_with_mutator(int fd, grpc_socket_mutator* mutator) {
392 GPR_ASSERT(mutator);
393 if (!grpc_socket_mutator_mutate_fd(mutator, fd)) {
394 return GRPC_ERROR_CREATE_FROM_STATIC_STRING("grpc_socket_mutator failed.");
395 }
396 return GRPC_ERROR_NONE;
397 }
398
grpc_apply_socket_mutator_in_args(int fd,const grpc_channel_args * args)399 grpc_error* grpc_apply_socket_mutator_in_args(int fd,
400 const grpc_channel_args* args) {
401 const grpc_arg* socket_mutator_arg =
402 grpc_channel_args_find(args, GRPC_ARG_SOCKET_MUTATOR);
403 if (socket_mutator_arg == nullptr) {
404 return GRPC_ERROR_NONE;
405 }
406 GPR_DEBUG_ASSERT(socket_mutator_arg->type == GRPC_ARG_POINTER);
407 grpc_socket_mutator* mutator =
408 static_cast<grpc_socket_mutator*>(socket_mutator_arg->value.pointer.p);
409 return grpc_set_socket_with_mutator(fd, mutator);
410 }
411
412 static gpr_once g_probe_ipv6_once = GPR_ONCE_INIT;
413 static int g_ipv6_loopback_available;
414
probe_ipv6_once(void)415 static void probe_ipv6_once(void) {
416 int fd = socket(AF_INET6, SOCK_STREAM, 0);
417 g_ipv6_loopback_available = 0;
418 if (fd < 0) {
419 gpr_log(GPR_INFO, "Disabling AF_INET6 sockets because socket() failed.");
420 } else {
421 grpc_sockaddr_in6 addr;
422 memset(&addr, 0, sizeof(addr));
423 addr.sin6_family = AF_INET6;
424 addr.sin6_addr.s6_addr[15] = 1; /* [::1]:0 */
425 if (bind(fd, reinterpret_cast<grpc_sockaddr*>(&addr), sizeof(addr)) == 0) {
426 g_ipv6_loopback_available = 1;
427 } else {
428 gpr_log(GPR_INFO,
429 "Disabling AF_INET6 sockets because ::1 is not available.");
430 }
431 close(fd);
432 }
433 }
434
grpc_ipv6_loopback_available(void)435 int grpc_ipv6_loopback_available(void) {
436 gpr_once_init(&g_probe_ipv6_once, probe_ipv6_once);
437 return g_ipv6_loopback_available;
438 }
439
error_for_fd(int fd,const grpc_resolved_address * addr)440 static grpc_error* error_for_fd(int fd, const grpc_resolved_address* addr) {
441 if (fd >= 0) return GRPC_ERROR_NONE;
442 std::string addr_str = grpc_sockaddr_to_string(addr, false);
443 grpc_error* err = grpc_error_set_str(
444 GRPC_OS_ERROR(errno, "socket"), GRPC_ERROR_STR_TARGET_ADDRESS,
445 grpc_slice_from_copied_string(addr_str.c_str()));
446 return err;
447 }
448
grpc_create_dualstack_socket(const grpc_resolved_address * resolved_addr,int type,int protocol,grpc_dualstack_mode * dsmode,int * newfd)449 grpc_error* grpc_create_dualstack_socket(
450 const grpc_resolved_address* resolved_addr, int type, int protocol,
451 grpc_dualstack_mode* dsmode, int* newfd) {
452 return grpc_create_dualstack_socket_using_factory(
453 nullptr, resolved_addr, type, protocol, dsmode, newfd);
454 }
455
create_socket(grpc_socket_factory * factory,int domain,int type,int protocol)456 static int create_socket(grpc_socket_factory* factory, int domain, int type,
457 int protocol) {
458 return (factory != nullptr)
459 ? grpc_socket_factory_socket(factory, domain, type, protocol)
460 : socket(domain, type, protocol);
461 }
462
grpc_create_dualstack_socket_using_factory(grpc_socket_factory * factory,const grpc_resolved_address * resolved_addr,int type,int protocol,grpc_dualstack_mode * dsmode,int * newfd)463 grpc_error* grpc_create_dualstack_socket_using_factory(
464 grpc_socket_factory* factory, const grpc_resolved_address* resolved_addr,
465 int type, int protocol, grpc_dualstack_mode* dsmode, int* newfd) {
466 const grpc_sockaddr* addr =
467 reinterpret_cast<const grpc_sockaddr*>(resolved_addr->addr);
468 int family = addr->sa_family;
469 if (family == AF_INET6) {
470 if (grpc_ipv6_loopback_available()) {
471 *newfd = create_socket(factory, family, type, protocol);
472 } else {
473 *newfd = -1;
474 errno = EAFNOSUPPORT;
475 }
476 /* Check if we've got a valid dualstack socket. */
477 if (*newfd >= 0 && grpc_set_socket_dualstack(*newfd)) {
478 *dsmode = GRPC_DSMODE_DUALSTACK;
479 return GRPC_ERROR_NONE;
480 }
481 /* If this isn't an IPv4 address, then return whatever we've got. */
482 if (!grpc_sockaddr_is_v4mapped(resolved_addr, nullptr)) {
483 *dsmode = GRPC_DSMODE_IPV6;
484 return error_for_fd(*newfd, resolved_addr);
485 }
486 /* Fall back to AF_INET. */
487 if (*newfd >= 0) {
488 close(*newfd);
489 }
490 family = AF_INET;
491 }
492 *dsmode = family == AF_INET ? GRPC_DSMODE_IPV4 : GRPC_DSMODE_NONE;
493 *newfd = create_socket(factory, family, type, protocol);
494 return error_for_fd(*newfd, resolved_addr);
495 }
496
grpc_htons(uint16_t hostshort)497 uint16_t grpc_htons(uint16_t hostshort) { return htons(hostshort); }
498
grpc_ntohs(uint16_t netshort)499 uint16_t grpc_ntohs(uint16_t netshort) { return ntohs(netshort); }
500
grpc_htonl(uint32_t hostlong)501 uint32_t grpc_htonl(uint32_t hostlong) { return htonl(hostlong); }
502
grpc_ntohl(uint32_t netlong)503 uint32_t grpc_ntohl(uint32_t netlong) { return ntohl(netlong); }
504
grpc_inet_pton(int af,const char * src,void * dst)505 int grpc_inet_pton(int af, const char* src, void* dst) {
506 return inet_pton(af, src, dst);
507 }
508
grpc_inet_ntop(int af,const void * src,char * dst,size_t size)509 const char* grpc_inet_ntop(int af, const void* src, char* dst, size_t size) {
510 GPR_ASSERT(size <= (socklen_t)-1);
511 return inet_ntop(af, src, dst, static_cast<socklen_t>(size));
512 }
513
514 #endif
515