Fix skiaserve in debug mode

tools/skiaserve/skiaserve.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "Request.h"
 #include "Response.h"
 
 #include "SkCommandLineFlags.h"
 
 #include "microhttpd.h"
 
 #include "urlhandlers/UrlHandler.h"
+
+#include <errno.h>
 #include <sys/socket.h>
 #include <arpa/inet.h>
 
 using namespace Response;
 
 DEFINE_int32(port, 8888, "The port to listen on.");
-DEFINE_string(address, "localhost", "The address to bind to.");
+DEFINE_string(address, "127.0.0.1", "The address to bind to.");
 
 class UrlManager {
 public:
     UrlManager() {
         // Register handlers
         fHandlers.push_back(new RootHandler);
         fHandlers.push_back(new PostHandler);
         fHandlers.push_back(new ImgHandler);
         fHandlers.push_back(new ClipAlphaHandler);
         fHandlers.push_back(new EnableGPUHandler);
@@ skipping 42 matching lines @@
     }
     return result;
 }
 
 int skiaserve_main() {
     Request request(SkString("/data")); // This simple server has one request
 
     struct sockaddr_in address;
     address.sin_family = AF_INET;
     address.sin_port = htons(FLAGS_port);
-    inet_pton(AF_INET, FLAGS_address[0], &address.sin_addr);
+    int result = inet_pton(AF_INET, FLAGS_address[0], &address.sin_addr);
+    if (result != 1) {
+        printf("inet_pton for %s:%d failed with return %d %s\n", 
+                FLAGS_address[0], FLAGS_port, result, strerror(errno));
+        return 1;
+    }
 
     printf("Visit http://%s:%d in your browser.\n", FLAGS_address[0], FLAGS_port);
 
     struct MHD_Daemon* daemon;
     daemon = MHD_start_daemon(MHD_USE_SELECT_INTERNALLY
 #ifdef SK_DEBUG
                               | MHD_USE_DEBUG
 #endif  
                               , FLAGS_port, nullptr, nullptr,
                               &answer_to_connection, &request,
                               MHD_OPTION_SOCK_ADDR, &address,
                               MHD_OPTION_END);
     if (NULL == daemon) {
         SkDebugf("Could not initialize daemon\n");
         return 1;
     }
 
     getchar();
     MHD_stop_daemon(daemon);
     return 0;
 }
 
 #if !defined SK_BUILD_FOR_IOS
 int main(int argc, char** argv) {
     SkCommandLineFlags::Parse(argc, argv);
     return skiaserve_main();
 }
 #endif