Start better error reporting for sockets

runtime/bin/socket_linux.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include <arpa/inet.h>
 #include <errno.h>
 #include <netdb.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ skipping 89 matching lines @@
   }
   return ntohs(socket_address.sin_port);
 }
 
 
 intptr_t Socket::GetStdioHandle(int num) {
   return static_cast<intptr_t>(num);
 }
 
 
+const char* Socket::LookupIPv4Address(char* host, OSError** os_error) {
+  // Perform a name lookup for an IPv4 address.
+  struct addrinfo hints;
+  memset(&hints, 0, sizeof(hints));
+  hints.ai_family = AF_INET;
+  hints.ai_socktype = SOCK_STREAM;
+  hints.ai_protocol = IPPROTO_TCP;
+  struct addrinfo* info = NULL;
+  int status = getaddrinfo(host, 0, &hints, &info);
+  if (status != 0) {
+    ASSERT(*os_error == NULL);
+    *os_error = new OSError(status,
+                            gai_strerror(status),
+                            OSError::kGetAddressInfo);
+    (*os_error)->set_code(status);
+    (*os_error)->SetMessage(gai_strerror(status));
+    return NULL;
+  }
+  // Convert the address into IPv4 dotted decomal notation.

[Mads Ager (google), 2012/03/14 12:51:51]

decomal -> decimal

[Søren Gjesse, 2012/03/19 10:05:43]

Done.

+  char* buffer = reinterpret_cast<char*>(malloc(INET_ADDRSTRLEN));
+  sockaddr_in *sockaddr = reinterpret_cast<sockaddr_in *>(info->ai_addr);
+  const char* result = inet_ntop(AF_INET,
+                                 reinterpret_cast<void *>(&sockaddr->sin_addr),
+                                 buffer,
+                                 INET_ADDRSTRLEN);
+  if (result == NULL) {
+    free(buffer);
+    return NULL;
+  }
+  ASSERT(result == buffer);
+  return buffer;
+}
+
+
 intptr_t ServerSocket::CreateBindListen(const char* host,
                                         intptr_t port,
                                         intptr_t backlog) {
   intptr_t fd;
   struct sockaddr_in server_address;
 
   fd = TEMP_FAILURE_RETRY(socket(AF_INET, SOCK_STREAM, 0));
   if (fd < 0) {
     fprintf(stderr, "Error CreateBind: %s\n", strerror(errno));
     return -1;
@@ skipping 31 matching lines @@
   struct sockaddr clientaddr;
   socklen_t addrlen = sizeof(clientaddr);
   socket = TEMP_FAILURE_RETRY(accept(fd, &clientaddr, &addrlen));
   if (socket < 0) {
     fprintf(stderr, "Error Accept: %s\n", strerror(errno));
   } else {
     FDUtils::SetNonBlocking(socket);
   }
   return socket;
 }