Cleanup mojo_shell and sample_app a bit

mojo/shell/sample_app.cc

-// Copyright 2013 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include <stdio.h>
-
-#include "base/basictypes.h"
-#include "mojo/public/system/core.h"
-#include "mojo/system/core_impl.h"
-
-#if defined(OS_WIN)
-#if !defined(CDECL)
-#define CDECL __cdecl
-#endif
-#define SAMPLE_APP_EXPORT __declspec(dllexport)
-#else
-#define CDECL
-#define SAMPLE_APP_EXPORT __attribute__((visibility("default")))
-#endif
-
-char* ReadStringFromPipe(mojo::Handle pipe) {
-  uint32_t len = 0;
-  char* buf = NULL;
-  MojoResult result = mojo::ReadMessage(pipe, buf, &len, NULL, NULL,
-                                        MOJO_READ_MESSAGE_FLAG_NONE);
-  if (result == MOJO_RESULT_RESOURCE_EXHAUSTED) {
-    buf = new char[len];
-    result = mojo::ReadMessage(pipe, buf, &len, NULL, NULL,
-                               MOJO_READ_MESSAGE_FLAG_NONE);
-  }
-  if (result < MOJO_RESULT_OK) {
-    // Failure..
-    if (buf)
-      delete[] buf;
-    return NULL;
-  }
-  return buf;
-}
-
-class SampleMessageWaiter {
- public:
-  explicit SampleMessageWaiter(mojo::Handle pipe) : pipe_(pipe) {}
-  ~SampleMessageWaiter() {}
-
-  void Read() {
-    char* string = ReadStringFromPipe(pipe_);
-    if (string) {
-      printf("Read string from pipe: %s\n", string);
-      delete[] string;
-      string = NULL;
-    }
-  }
-
-  void WaitAndRead() {
-    MojoResult result = mojo::Wait(pipe_, MOJO_WAIT_FLAG_READABLE, 100);
-    if (result < MOJO_RESULT_OK) {
-      // Failure...
-    }
-
-    Read();
-  }
-
- private:
-
-  mojo::Handle pipe_;
-  DISALLOW_COPY_AND_ASSIGN(SampleMessageWaiter);
-};
-
-extern "C" SAMPLE_APP_EXPORT MojoResult CDECL MojoMain(
-    mojo::Handle pipe) {
-  SampleMessageWaiter(pipe).WaitAndRead();
-  return MOJO_RESULT_OK;
-}