root/remoting/host/plugin/host_plugin.cc

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DEFINITIONS

This source file includes following definitions.
  1. __divdi3
  2. __udivdi3
  3. scriptable_object_
  4. Init
  5. Save
  6. GetScriptableObject
  7. RunOnPluginThread
  8. SetWindow
  9. NPDelayedTaskSpringboard
  10. ScriptableFromObject
  11. Allocate
  12. Deallocate
  13. Invalidate
  14. HasMethod
  15. InvokeDefault
  16. Invoke
  17. HasProperty
  18. GetProperty
  19. SetProperty
  20. RemoveProperty
  21. Enumerate
  22. InitializePlugin
  23. ShutdownPlugin
  24. PluginFromInstance
  25. CreatePlugin
  26. DestroyPlugin
  27. GetValue
  28. HandleEvent
  29. SetWindow
  30. DllMain
  31. NP_GetEntryPoints
  32. NP_Initialize
  33. NP_Shutdown
  34. NP_GetMIMEDescription
  35. NP_GetValue

// Copyright (c) 2012 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 <string.h>

#include <string>
#include <vector>

#include "base/at_exit.h"
#include "base/basictypes.h"
#include "base/command_line.h"
#include "base/logging.h"
#include "base/strings/stringize_macros.h"
#include "net/socket/ssl_server_socket.h"
#include "remoting/base/plugin_thread_task_runner.h"
#include "remoting/base/resources.h"
#include "remoting/base/string_resources.h"
#include "remoting/host/plugin/host_log_handler.h"
#include "remoting/host/plugin/host_plugin_utils.h"
#include "remoting/host/plugin/host_script_object.h"
#if defined(OS_WIN)
#include "ui/gfx/win/dpi.h"
#endif
#include "third_party/npapi/bindings/npapi.h"
#include "third_party/npapi/bindings/npfunctions.h"
#include "third_party/npapi/bindings/npruntime.h"
#include "ui/base/l10n/l10n_util.h"

// Symbol export is handled with a separate def file on Windows.
#if defined (__GNUC__) && __GNUC__ >= 4
#define EXPORT __attribute__((visibility("default")))
#else
#define EXPORT
#endif

#if defined(OS_WIN)
// TODO(wez): libvpx expects these 64-bit division functions to be provided
// by libgcc.a, which we aren't linked against.  These implementations can
// be removed once we have native MSVC libvpx builds for Windows.
extern "C" {

int64_t __cdecl __divdi3(int64_t a, int64_t b) {
  return a / b;
}
uint64_t __cdecl __udivdi3(uint64_t a, uint64_t b) {
  return a / b;
}

}
#endif

using remoting::g_npnetscape_funcs;
using remoting::HostLogHandler;
using remoting::HostNPScriptObject;
using remoting::StringFromNPIdentifier;

namespace {

bool g_initialized = false;

base::AtExitManager* g_at_exit_manager = NULL;

// The plugin name and description returned by GetValue().
std::string* g_ui_name = NULL;
std::string* g_ui_description = NULL;

// NPAPI plugin implementation for remoting host.
// Documentation for most of the calls in this class can be found here:
// https://developer.mozilla.org/en/Gecko_Plugin_API_Reference/Scripting_plugins
class HostNPPlugin : public remoting::PluginThreadTaskRunner::Delegate {
 public:
  // |mode| is the display mode of plug-in. Values:
  // NP_EMBED: (1) Instance was created by an EMBED tag and shares the browser
  //               window with other content.
  // NP_FULL: (2) Instance was created by a separate file and is the primary
  //              content in the window.
  HostNPPlugin(NPP instance, uint16 mode)
      : instance_(instance),
        scriptable_object_(NULL) {
    plugin_task_runner_ = new remoting::PluginThreadTaskRunner(this);
    plugin_auto_task_runner_ =
        new remoting::AutoThreadTaskRunner(
            plugin_task_runner_,
            base::Bind(&remoting::PluginThreadTaskRunner::Quit,
                       plugin_task_runner_));
  }

  virtual ~HostNPPlugin() {
    if (scriptable_object_) {
      DCHECK_EQ(scriptable_object_->referenceCount, 1UL);
      g_npnetscape_funcs->releaseobject(scriptable_object_);
      scriptable_object_ = NULL;
    }

    // Process tasks on |plugin_task_runner_| until all references to
    // |plugin_auto_task_runner_| have been dropped. This requires that the
    // browser has dropped any script object references - see above.
    plugin_auto_task_runner_ = NULL;
    plugin_task_runner_->DetachAndRunShutdownLoop();
  }

  bool Init(int16 argc, char** argn, char** argv, NPSavedData* saved) {
#if defined(OS_MACOSX)
    // Use the modern CoreGraphics and Cocoa models when available, since
    // QuickDraw and Carbon are deprecated.
    // The drawing and event models don't change anything for this plugin, since
    // none of the functions affected by the models actually do anything.
    // This does however keep the plugin from breaking when Chromium eventually
    // drops support for QuickDraw and Carbon, and it also keeps the browser
    // from sending Null Events once a second to support old Carbon based
    // timers.
    // Chromium should always be supporting the newer models.

    // Sanity check to see if Chromium supports the CoreGraphics drawing model.
    NPBool supports_core_graphics = false;
    NPError err = g_npnetscape_funcs->getvalue(instance_,
                                               NPNVsupportsCoreGraphicsBool,
                                               &supports_core_graphics);
    if (err == NPERR_NO_ERROR && supports_core_graphics) {
      // Switch to CoreGraphics drawing model.
      g_npnetscape_funcs->setvalue(instance_, NPPVpluginDrawingModel,
          reinterpret_cast<void*>(NPDrawingModelCoreGraphics));
    } else {
      LOG(ERROR) << "No Core Graphics support";
      return false;
    }

    // Sanity check to see if Chromium supports the Cocoa event model.
    NPBool supports_cocoa = false;
    err = g_npnetscape_funcs->getvalue(instance_, NPNVsupportsCocoaBool,
                                       &supports_cocoa);
    if (err == NPERR_NO_ERROR && supports_cocoa) {
      // Switch to Cocoa event model.
      g_npnetscape_funcs->setvalue(instance_, NPPVpluginEventModel,
          reinterpret_cast<void*>(NPEventModelCocoa));
    } else {
      LOG(ERROR) << "No Cocoa Event Model support";
      return false;
    }
#endif  // OS_MACOSX
    net::EnableSSLServerSockets();
    return true;
  }

  bool Save(NPSavedData** saved) {
    return true;
  }

  NPObject* GetScriptableObject() {
    if (!scriptable_object_) {
      // Must be static. If it is a temporary, objects created by this
      // method will fail in weird and wonderful ways later.
      static NPClass npc_ref_object = {
        NP_CLASS_STRUCT_VERSION,
        &Allocate,
        &Deallocate,
        &Invalidate,
        &HasMethod,
        &Invoke,
        &InvokeDefault,
        &HasProperty,
        &GetProperty,
        &SetProperty,
        &RemoveProperty,
        &Enumerate,
        NULL
      };
      scriptable_object_ = g_npnetscape_funcs->createobject(instance_,
                                                            &npc_ref_object);
    }
    return scriptable_object_;
  }

  // PluginThreadTaskRunner::Delegate implementation.
  virtual bool RunOnPluginThread(
      base::TimeDelta delay, void(function)(void*), void* data) OVERRIDE {
    if (delay == base::TimeDelta()) {
      g_npnetscape_funcs->pluginthreadasynccall(instance_, function, data);
    } else {
      base::AutoLock auto_lock(timers_lock_);
      uint32_t timer_id = g_npnetscape_funcs->scheduletimer(
          instance_, delay.InMilliseconds(), false, &NPDelayedTaskSpringboard);
      DelayedTask task = {function, data};
      timers_[timer_id] = task;
    }
    return true;
  }

  void SetWindow(NPWindow* np_window) {
    if (scriptable_object_) {
      ScriptableFromObject(scriptable_object_)->SetWindow(np_window);
    }
  }

  static void NPDelayedTaskSpringboard(NPP npp, uint32_t timer_id) {
    HostNPPlugin* self = reinterpret_cast<HostNPPlugin*>(npp->pdata);
    DelayedTask task;
    {
      base::AutoLock auto_lock(self->timers_lock_);
      std::map<uint32_t, DelayedTask>::iterator it =
          self->timers_.find(timer_id);
      CHECK(it != self->timers_.end());
      task = it->second;
      self->timers_.erase(it);
    }
    task.function(task.data);
  }

 private:
  struct ScriptableNPObject : public NPObject {
    HostNPScriptObject* scriptable_object;
  };

  struct DelayedTask {
    void (*function)(void*);
    void* data;
  };

  static HostNPScriptObject* ScriptableFromObject(NPObject* obj) {
    return reinterpret_cast<ScriptableNPObject*>(obj)->scriptable_object;
  }

  static NPObject* Allocate(NPP npp, NPClass* aClass) {
    VLOG(2) << "static Allocate";
    ScriptableNPObject* object =
        reinterpret_cast<ScriptableNPObject*>(
            g_npnetscape_funcs->memalloc(sizeof(ScriptableNPObject)));
    HostNPPlugin* plugin = reinterpret_cast<HostNPPlugin*>(npp->pdata);

    object->_class = aClass;
    object->referenceCount = 1;
    object->scriptable_object =
        new HostNPScriptObject(npp, object, plugin->plugin_auto_task_runner_);
    return object;
  }

  static void Deallocate(NPObject* npobj) {
    VLOG(2) << "static Deallocate";
    if (npobj) {
      Invalidate(npobj);
      g_npnetscape_funcs->memfree(npobj);
    }
  }

  static void Invalidate(NPObject* npobj) {
    if (npobj) {
      ScriptableNPObject* object = reinterpret_cast<ScriptableNPObject*>(npobj);
      if (object->scriptable_object) {
        delete object->scriptable_object;
        object->scriptable_object = NULL;
      }
    }
  }

  static bool HasMethod(NPObject* obj, NPIdentifier method_name) {
    VLOG(2) << "static HasMethod";
    HostNPScriptObject* scriptable = ScriptableFromObject(obj);
    if (!scriptable) return false;
    std::string method_name_string = StringFromNPIdentifier(method_name);
    if (method_name_string.empty())
      return false;
    return scriptable->HasMethod(method_name_string);
  }

  static bool InvokeDefault(NPObject* obj,
                            const NPVariant* args,
                            uint32_t argCount,
                            NPVariant* result) {
    VLOG(2) << "static InvokeDefault";
    HostNPScriptObject* scriptable = ScriptableFromObject(obj);
    if (!scriptable) return false;
    return scriptable->InvokeDefault(args, argCount, result);
  }

  static bool Invoke(NPObject* obj,
                     NPIdentifier method_name,
                     const NPVariant* args,
                     uint32_t argCount,
                     NPVariant* result) {
    VLOG(2) << "static Invoke";
    HostNPScriptObject* scriptable = ScriptableFromObject(obj);
    if (!scriptable)
      return false;
    std::string method_name_string = StringFromNPIdentifier(method_name);
    if (method_name_string.empty())
      return false;
    return scriptable->Invoke(method_name_string, args, argCount, result);
  }

  static bool HasProperty(NPObject* obj, NPIdentifier property_name) {
    VLOG(2) << "static HasProperty";
    HostNPScriptObject* scriptable = ScriptableFromObject(obj);
    if (!scriptable) return false;
    std::string property_name_string = StringFromNPIdentifier(property_name);
    if (property_name_string.empty())
      return false;
    return scriptable->HasProperty(property_name_string);
  }

  static bool GetProperty(NPObject* obj,
                          NPIdentifier property_name,
                          NPVariant* result) {
    VLOG(2) << "static GetProperty";
    HostNPScriptObject* scriptable = ScriptableFromObject(obj);
    if (!scriptable) return false;
    std::string property_name_string = StringFromNPIdentifier(property_name);
    if (property_name_string.empty())
      return false;
    return scriptable->GetProperty(property_name_string, result);
  }

  static bool SetProperty(NPObject* obj,
                          NPIdentifier property_name,
                          const NPVariant* value) {
    VLOG(2) << "static SetProperty";
    HostNPScriptObject* scriptable = ScriptableFromObject(obj);
    if (!scriptable) return false;
    std::string property_name_string = StringFromNPIdentifier(property_name);
    if (property_name_string.empty())
      return false;
    return scriptable->SetProperty(property_name_string, value);
  }

  static bool RemoveProperty(NPObject* obj, NPIdentifier property_name) {
    VLOG(2) << "static RemoveProperty";
    HostNPScriptObject* scriptable = ScriptableFromObject(obj);
    if (!scriptable) return false;
    std::string property_name_string = StringFromNPIdentifier(property_name);
    if (property_name_string.empty())
      return false;
    return scriptable->RemoveProperty(property_name_string);
  }

  static bool Enumerate(NPObject* obj,
                        NPIdentifier** value,
                        uint32_t* count) {
    VLOG(2) << "static Enumerate";
    HostNPScriptObject* scriptable = ScriptableFromObject(obj);
    if (!scriptable) return false;
    std::vector<std::string> values;
    bool is_good = scriptable->Enumerate(&values);
    if (is_good) {
      *count = values.size();
      *value = reinterpret_cast<NPIdentifier*>(
          g_npnetscape_funcs->memalloc(sizeof(NPIdentifier) * (*count)));
      for (uint32_t i = 0; i < *count; ++i) {
        (*value)[i] =
            g_npnetscape_funcs->getstringidentifier(values[i].c_str());
      }
    }
    return is_good;
  }

  NPP instance_;
  NPObject* scriptable_object_;

  scoped_refptr<remoting::PluginThreadTaskRunner> plugin_task_runner_;
  scoped_refptr<remoting::AutoThreadTaskRunner> plugin_auto_task_runner_;

  std::map<uint32_t, DelayedTask> timers_;
  base::Lock timers_lock_;
};

void InitializePlugin() {
  if (g_initialized)
    return;

  g_initialized = true;
  g_at_exit_manager = new base::AtExitManager;

  // Init an empty command line for common objects that use it.
  CommandLine::Init(0, NULL);

  if (remoting::LoadResources("")) {
    g_ui_name = new std::string(
        l10n_util::GetStringUTF8(IDS_REMOTING_HOST_PLUGIN_NAME));
    g_ui_description = new std::string(
        l10n_util::GetStringUTF8(IDS_REMOTING_HOST_PLUGIN_DESCRIPTION));
  } else {
    g_ui_name = new std::string();
    g_ui_description = new std::string();
  }
}

void ShutdownPlugin() {
  delete g_ui_name;
  delete g_ui_description;

  remoting::UnloadResources();

  delete g_at_exit_manager;
}

// Utility functions to map NPAPI Entry Points to C++ Objects.
HostNPPlugin* PluginFromInstance(NPP instance) {
  return reinterpret_cast<HostNPPlugin*>(instance->pdata);
}

NPError CreatePlugin(NPMIMEType pluginType,
                     NPP instance,
                     uint16 mode,
                     int16 argc,
                     char** argn,
                     char** argv,
                     NPSavedData* saved) {
  VLOG(2) << "CreatePlugin";

  // Register a global log handler.
  // The LogMessage registration code is not thread-safe, so we need to perform
  // this while we're running in a single thread.
  HostLogHandler::RegisterLogMessageHandler();

  HostNPPlugin* plugin = new HostNPPlugin(instance, mode);
  instance->pdata = plugin;
  if (!plugin->Init(argc, argn, argv, saved)) {
    delete plugin;
    instance->pdata = NULL;
    return NPERR_INVALID_PLUGIN_ERROR;
  } else {
    return NPERR_NO_ERROR;
  }
}

NPError DestroyPlugin(NPP instance,
                      NPSavedData** save) {
  VLOG(2) << "DestroyPlugin";

  // Normally, we would unregister the global log handler that we registered
  // in CreatePlugin. However, the LogHandler registration code is not thread-
  // safe so we could crash if we update (register or unregister) the
  // LogHandler while it's being read on another thread.
  // At this point, all our threads should be shutdown, but it's safer to leave
  // the handler registered until we're completely destroyed.

  HostNPPlugin* plugin = PluginFromInstance(instance);
  if (plugin) {
    plugin->Save(save);
    delete plugin;
    instance->pdata = NULL;
    return NPERR_NO_ERROR;
  } else {
    return NPERR_INVALID_PLUGIN_ERROR;
  }
}

NPError GetValue(NPP instance, NPPVariable variable, void* value) {
  // NP_GetValue() can be called before NP_Initialize().
  InitializePlugin();

  switch(variable) {
  default:
    VLOG(2) << "GetValue - default " << variable;
    return NPERR_GENERIC_ERROR;
  case NPPVpluginNameString:
    VLOG(2) << "GetValue - name string";
    *reinterpret_cast<const char**>(value) = g_ui_name->c_str();
    break;
  case NPPVpluginDescriptionString:
    VLOG(2) << "GetValue - description string";
    *reinterpret_cast<const char**>(value) = g_ui_description->c_str();
    break;
  case NPPVpluginNeedsXEmbed:
    VLOG(2) << "GetValue - NeedsXEmbed";
    *(static_cast<NPBool*>(value)) = true;
    break;
  case NPPVpluginScriptableNPObject:
    VLOG(2) << "GetValue - scriptable object";
    HostNPPlugin* plugin = PluginFromInstance(instance);
    if (!plugin)
      return NPERR_INVALID_PLUGIN_ERROR;
    NPObject* scriptable_object = plugin->GetScriptableObject();
    g_npnetscape_funcs->retainobject(scriptable_object);
    *reinterpret_cast<NPObject**>(value) = scriptable_object;
    break;
  }
  return NPERR_NO_ERROR;
}

NPError HandleEvent(NPP instance, void* ev) {
  VLOG(2) << "HandleEvent";
  return NPERR_NO_ERROR;
}

NPError SetWindow(NPP instance, NPWindow* pNPWindow) {
  VLOG(2) << "SetWindow";
  HostNPPlugin* plugin = PluginFromInstance(instance);
  if (plugin) {
    plugin->SetWindow(pNPWindow);
  }
  return NPERR_NO_ERROR;
}

}  // namespace

#if defined(OS_WIN)
BOOL APIENTRY DllMain(HMODULE hModule, DWORD dwReason, LPVOID lpReserved) {
  switch (dwReason) {
    case DLL_PROCESS_ATTACH:
      DisableThreadLibraryCalls(hModule);
      break;
    case DLL_PROCESS_DETACH:
    case DLL_THREAD_ATTACH:
    case DLL_THREAD_DETACH:
      break;
  }
  return TRUE;
}
#endif

// The actual required NPAPI Entry points

extern "C" {

EXPORT NPError API_CALL NP_GetEntryPoints(NPPluginFuncs* nppfuncs) {
  VLOG(2) << "NP_GetEntryPoints";
  nppfuncs->version = (NP_VERSION_MAJOR << 8) | NP_VERSION_MINOR;
  nppfuncs->newp = &CreatePlugin;
  nppfuncs->destroy = &DestroyPlugin;
  nppfuncs->getvalue = &GetValue;
  nppfuncs->event = &HandleEvent;
  nppfuncs->setwindow = &SetWindow;

  return NPERR_NO_ERROR;
}

EXPORT NPError API_CALL NP_Initialize(NPNetscapeFuncs* npnetscape_funcs
#if defined(OS_POSIX) && !defined(OS_MACOSX)
                            , NPPluginFuncs* nppfuncs
#endif
                            ) {
  VLOG(2) << "NP_Initialize";
  InitializePlugin();

  if(npnetscape_funcs == NULL)
    return NPERR_INVALID_FUNCTABLE_ERROR;

  if(((npnetscape_funcs->version & 0xff00) >> 8) > NP_VERSION_MAJOR)
    return NPERR_INCOMPATIBLE_VERSION_ERROR;

  g_npnetscape_funcs = npnetscape_funcs;
#if defined(OS_POSIX) && !defined(OS_MACOSX)
  NP_GetEntryPoints(nppfuncs);
#endif

#if defined(OS_WIN)
  gfx::EnableHighDPISupport();
#endif

  return NPERR_NO_ERROR;
}

EXPORT NPError API_CALL NP_Shutdown() {
  VLOG(2) << "NP_Shutdown";
  ShutdownPlugin();

  return NPERR_NO_ERROR;
}

#if defined(OS_POSIX) && !defined(OS_MACOSX)
EXPORT const char* API_CALL NP_GetMIMEDescription(void) {
  VLOG(2) << "NP_GetMIMEDescription";
  return STRINGIZE(HOST_PLUGIN_MIME_TYPE) "::";
}

EXPORT NPError API_CALL NP_GetValue(void* npp,
                                    NPPVariable variable,
                                    void* value) {
  return GetValue((NPP)npp, variable, value);
}
#endif

}  // extern "C"

/* [<][>][^][v][top][bottom][index][help] */