1 files changed, 208 insertions, 0 deletions
diff --git a/src/core/lib/iomgr/socket_utils_common_posix.c b/src/core/lib/iomgr/socket_utils_common_posix.c
new file mode 100644
index 0000000000..9dbc2784e4
--- /dev/null
+++ b/src/core/lib/iomgr/socket_utils_common_posix.c
@@ -0,0 +1,208 @@
+/*
+ *
+ * Copyright 2015-2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <grpc/support/port_platform.h>
+
+#ifdef GPR_POSIX_SOCKET
+
+#include "src/core/lib/iomgr/socket_utils_posix.h"
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <grpc/support/host_port.h>
+#include <grpc/support/log.h>
+#include <grpc/support/port_platform.h>
+#include <grpc/support/sync.h>
+#include "src/core/lib/iomgr/sockaddr_utils.h"
+#include "src/core/lib/support/string.h"
+
+/* set a socket to non blocking mode */
+int grpc_set_socket_nonblocking(int fd, int non_blocking) {
+  int oldflags = fcntl(fd, F_GETFL, 0);
+  if (oldflags < 0) {
+    return 0;
+  }
+
+  if (non_blocking) {
+    oldflags |= O_NONBLOCK;
+  } else {
+    oldflags &= ~O_NONBLOCK;
+  }
+
+  if (fcntl(fd, F_SETFL, oldflags) != 0) {
+    return 0;
+  }
+
+  return 1;
+}
+
+int grpc_set_socket_no_sigpipe_if_possible(int fd) {
+#ifdef GPR_HAVE_SO_NOSIGPIPE
+  int val = 1;
+  int newval;
+  socklen_t intlen = sizeof(newval);
+  return 0 == setsockopt(fd, SOL_SOCKET, SO_NOSIGPIPE, &val, sizeof(val)) &&
+         0 == getsockopt(fd, SOL_SOCKET, SO_NOSIGPIPE, &newval, &intlen) &&
+         (newval != 0) == val;
+#else
+  return 1;
+#endif
+}
+
+/* set a socket to close on exec */
+int grpc_set_socket_cloexec(int fd, int close_on_exec) {
+  int oldflags = fcntl(fd, F_GETFD, 0);
+  if (oldflags < 0) {
+    return 0;
+  }
+
+  if (close_on_exec) {
+    oldflags |= FD_CLOEXEC;
+  } else {
+    oldflags &= ~FD_CLOEXEC;
+  }
+
+  if (fcntl(fd, F_SETFD, oldflags) != 0) {
+    return 0;
+  }
+
+  return 1;
+}
+
+/* set a socket to reuse old addresses */
+int grpc_set_socket_reuse_addr(int fd, int reuse) {
+  int val = (reuse != 0);
+  int newval;
+  socklen_t intlen = sizeof(newval);
+  return 0 == setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) &&
+         0 == getsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &newval, &intlen) &&
+         (newval != 0) == val;
+}
+
+/* disable nagle */
+int grpc_set_socket_low_latency(int fd, int low_latency) {
+  int val = (low_latency != 0);
+  int newval;
+  socklen_t intlen = sizeof(newval);
+  return 0 == setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val)) &&
+         0 == getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &newval, &intlen) &&
+         (newval != 0) == val;
+}
+
+static gpr_once g_probe_ipv6_once = GPR_ONCE_INIT;
+static int g_ipv6_loopback_available;
+
+static void probe_ipv6_once(void) {
+  int fd = socket(AF_INET6, SOCK_STREAM, 0);
+  g_ipv6_loopback_available = 0;
+  if (fd < 0) {
+    gpr_log(GPR_INFO, "Disabling AF_INET6 sockets because socket() failed.");
+  } else {
+    struct sockaddr_in6 addr;
+    memset(&addr, 0, sizeof(addr));
+    addr.sin6_family = AF_INET6;
+    addr.sin6_addr.s6_addr[15] = 1; /* [::1]:0 */
+    if (bind(fd, (struct sockaddr *)&addr, sizeof(addr)) == 0) {
+      g_ipv6_loopback_available = 1;
+    } else {
+      gpr_log(GPR_INFO,
+              "Disabling AF_INET6 sockets because ::1 is not available.");
+    }
+    close(fd);
+  }
+}
+
+int grpc_ipv6_loopback_available(void) {
+  gpr_once_init(&g_probe_ipv6_once, probe_ipv6_once);
+  return g_ipv6_loopback_available;
+}
+
+/* This should be 0 in production, but it may be enabled for testing or
+   debugging purposes, to simulate an environment where IPv6 sockets can't
+   also speak IPv4. */
+int grpc_forbid_dualstack_sockets_for_testing = 0;
+
+static int set_socket_dualstack(int fd) {
+  if (!grpc_forbid_dualstack_sockets_for_testing) {
+    const int off = 0;
+    return 0 == setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &off, sizeof(off));
+  } else {
+    /* Force an IPv6-only socket, for testing purposes. */
+    const int on = 1;
+    setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on));
+    return 0;
+  }
+}
+
+int grpc_create_dualstack_socket(const struct sockaddr *addr, int type,
+                                 int protocol, grpc_dualstack_mode *dsmode) {
+  int family = addr->sa_family;
+  if (family == AF_INET6) {
+    int fd;
+    if (grpc_ipv6_loopback_available()) {
+      fd = socket(family, type, protocol);
+    } else {
+      fd = -1;
+      errno = EAFNOSUPPORT;
+    }
+    /* Check if we've got a valid dualstack socket. */
+    if (fd >= 0 && set_socket_dualstack(fd)) {
+      *dsmode = GRPC_DSMODE_DUALSTACK;
+      return fd;
+    }
+    /* If this isn't an IPv4 address, then return whatever we've got. */
+    if (!grpc_sockaddr_is_v4mapped(addr, NULL)) {
+      *dsmode = GRPC_DSMODE_IPV6;
+      return fd;
+    }
+    /* Fall back to AF_INET. */
+    if (fd >= 0) {
+      close(fd);
+    }
+    family = AF_INET;
+  }
+  *dsmode = family == AF_INET ? GRPC_DSMODE_IPV4 : GRPC_DSMODE_NONE;
+  return socket(family, type, protocol);
+}
+
+#endif