Add support for reading channel args

1 files changed, 73 insertions, 14 deletions

diff --git a/src/core/lib/iomgr/socket_utils_common_posix.cc b/src/core/lib/iomgr/socket_utils_common_posix.cc
index b7fc833608..4ef3d8319f 100644
--- a/src/core/lib/iomgr/socket_utils_common_posix.cc
+++ b/src/core/lib/iomgr/socket_utils_common_posix.cc
@@ -41,6 +41,7 @@
 #include <grpc/support/log.h>
 #include <grpc/support/sync.h>
 
+#include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/gpr/host_port.h"
 #include "src/core/lib/gpr/string.h"
 #include "src/core/lib/iomgr/sockaddr.h"
@@ -222,25 +223,83 @@ grpc_error* grpc_set_socket_low_latency(int fd, int low_latency) {
   return GRPC_ERROR_NONE;
 }
 
-#define DEFAULT_TCP_USER_TIMEOUT 20000 /* 20 seconds */
+/* The default values for TCP_USER_TIMEOUT are currently configured to be in
+ * line with the default values of KEEPALIVE_TIMEOUT as proposed in
+ * https://github.com/grpc/proposal/blob/master/A18-tcp-user-timeout.md */
+#define DEFAULT_CLIENT_TCP_USER_TIMEOUT_MS 20000 /* 20 seconds */
+#define DEFAULT_SERVER_TCP_USER_TIMEOUT_MS 20000 /* 20 seconds */
+
+static int g_default_client_tcp_user_timeout_ms =
+    DEFAULT_CLIENT_TCP_USER_TIMEOUT_MS;
+static int g_default_server_tcp_user_timeout_ms =
+    DEFAULT_SERVER_TCP_USER_TIMEOUT_MS;
+static bool g_default_client_tcp_user_timeout_enabled = false;
+static bool g_default_server_tcp_user_timeout_enabled = true;
+
+void config_default_tcp_user_timeout(bool enable, int timeout, bool is_client) {
+  if (is_client) {
+    g_default_client_tcp_user_timeout_enabled = enable;
+    if (timeout > 0) {
+      g_default_client_tcp_user_timeout_ms = timeout;
+    }
+  } else {
+    g_default_server_tcp_user_timeout_enabled = enable;
+    if (timeout > 0) {
+      g_default_server_tcp_user_timeout_ms = timeout;
+    }
+  }
+}
 
 /* Set TCP_USER_TIMEOUT */
-grpc_error* grpc_set_socket_tcp_user_timeout(int fd, int val) {
+grpc_error* grpc_set_socket_tcp_user_timeout(
+    int fd, const grpc_channel_args* channel_args, bool is_client) {
 #ifdef GRPC_HAVE_TCP_USER_TIMEOUT
-  int newval;
-  socklen_t len = sizeof(newval);
-  if (val == 0) {
-    val = DEFAULT_TCP_USER_TIMEOUT;
-  }
-  if (0 != setsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &val, sizeof(val))) {
-    return GRPC_OS_ERROR(errno, "setsockopt(TCP_USER_TIMEOUT)");
+  bool enable;
+  int timeout;
+  if (is_client) {
+    enable = g_default_client_tcp_user_timeout_enabled;
+    timeout = g_default_client_tcp_user_timeout_ms;
+  } else {
+    enable = g_default_server_tcp_user_timeout_enabled;
+    timeout = g_default_server_tcp_user_timeout_ms;
   }
-  if (0 != getsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &newval, &len)) {
-    return GRPC_OS_ERROR(errno, "getsockopt(TCP_USER_TIMEOUT)");
+  if (channel_args) {
+    for (unsigned int i = 0; i < channel_args->num_args; i++) {
+      if (0 == strcmp(channel_args->args[i].key, GRPC_ARG_KEEPALIVE_TIME_MS)) {
+        const int value = grpc_channel_arg_get_integer(
+            &channel_args->args[i], grpc_integer_options{0, 1, INT_MAX});
+        /* Continue using default if value is 0 */
+        if (value == 0) {
+          continue;
+        }
+        /* Disable if value is INT_MAX */
+        enable = value != INT_MAX;
+      } else if (0 == strcmp(channel_args->args[i].key,
+                             GRPC_ARG_KEEPALIVE_TIMEOUT_MS)) {
+        const int value = grpc_channel_arg_get_integer(
+            &channel_args->args[i], grpc_integer_options{0, 1, INT_MAX});
+        /* Continue using default if value is 0 */
+        if (value == 0) {
+          continue;
+        }
+        timeout = value;
+      }
+    }
   }
-  if (newval != val) {
-    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
-        "Failed to set TCP_USER_TIMEOUT");
+  if (enable) {
+    int newval;
+    socklen_t len = sizeof(newval);
+    if (0 != setsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &timeout,
+                        sizeof(timeout))) {
+      return GRPC_OS_ERROR(errno, "setsockopt(TCP_USER_TIMEOUT)");
+    }
+    if (0 != getsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &newval, &len)) {
+      return GRPC_OS_ERROR(errno, "getsockopt(TCP_USER_TIMEOUT)");
+    }
+    if (newval != timeout) {
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+          "Failed to set TCP_USER_TIMEOUT");
+    }
   }
 #else
   gpr_log(GPR_INFO, "TCP_USER_TIMEOUT not supported for this platform");