mojo/shell/sample_app.cc

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include <stdio.h>
   6
   7 #include "base/basictypes.h"
   8 #include "mojo/public/system/core.h"
   9 #include "mojo/system/core_impl.h"
  10
  11 #if defined(OS_WIN)
  12 #if !defined(CDECL)
  13 #define CDECL __cdecl
  14 #endif
  15 #define SAMPLE_APP_EXPORT __declspec(dllexport)
  16 #else
  17 #define CDECL
  18 #define SAMPLE_APP_EXPORT __attribute__((visibility("default")))
  19 #endif
  20
  21 char* ReadStringFromPipe(mojo::Handle pipe) {
  22   uint32_t len = 0;
  23   char* buf = NULL;
  24   MojoResult result = mojo::ReadMessage(pipe, buf, &len, NULL, NULL,
  25                                         MOJO_READ_MESSAGE_FLAG_NONE);
  26   if (result == MOJO_RESULT_RESOURCE_EXHAUSTED) {
  27     buf = new char[len];
  28     result = mojo::ReadMessage(pipe, buf, &len, NULL, NULL,
  29                                MOJO_READ_MESSAGE_FLAG_NONE);
  30   }
  31   if (result < MOJO_RESULT_OK) {
  32     // Failure..
  33     if (buf)
  34       delete[] buf;
  35     return NULL;
  36   }
  37   return buf;
  38 }
  39
  40 class SampleMessageWaiter {
  41  public:
  42   explicit SampleMessageWaiter(mojo::Handle pipe) : pipe_(pipe) {}
  43   ~SampleMessageWaiter() {}
  44
  45   void Read() {
  46     char* string = ReadStringFromPipe(pipe_);
  47     if (string) {
  48       printf("Read string from pipe: %s\n", string);
  49       delete[] string;
  50       string = NULL;
  51     }
  52   }
  53
  54   void WaitAndRead() {
  55     MojoResult result = mojo::Wait(pipe_, MOJO_WAIT_FLAG_READABLE, 100);
  56     if (result < MOJO_RESULT_OK) {
  57       // Failure...
  58     }
  59
  60     Read();
  61   }
  62
  63  private:
  64
  65   mojo::Handle pipe_;
  66   DISALLOW_COPY_AND_ASSIGN(SampleMessageWaiter);
  67 };
  68
  69 extern "C" SAMPLE_APP_EXPORT MojoResult CDECL MojoMain(
  70     mojo::Handle pipe) {
  71   SampleMessageWaiter(pipe).WaitAndRead();
  72   return MOJO_RESULT_OK;
  73 }