embedding/browser/nsCommandHandler.cpp

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "nsCommandHandler.h"
   8 #include "nsWebBrowser.h"
   9 #include "nsDocShellTreeOwner.h"
  10
  11 #include "nsMemory.h"
  12 #include "nsPIDOMWindow.h"
  13
  14 nsCommandHandler::nsCommandHandler() :
  15     mWindow(nullptr)
  16 {
  17 }
  18
  19 nsCommandHandler::~nsCommandHandler()
  20 {
  21 }
  22
  23 nsresult nsCommandHandler::GetCommandHandler(nsICommandHandler **aCommandHandler)
  24 {
  25     NS_ENSURE_ARG_POINTER(aCommandHandler);
  26
  27     *aCommandHandler = nullptr;
  28     if (mWindow == nullptr)
  29     {
  30         return NS_ERROR_FAILURE;
  31     }
  32
  33     nsCOMPtr<nsPIDOMWindow> window(do_QueryInterface(mWindow));
  34     if (!window)
  35     {
  36         return NS_ERROR_FAILURE;
  37     }
  38
  39     // Get the document tree owner
  40
  41     nsCOMPtr<nsIDocShellTreeItem> docShellAsTreeItem =
  42       do_QueryInterface(window->GetDocShell());
  43     nsIDocShellTreeOwner *treeOwner = nullptr;
  44     docShellAsTreeItem->GetTreeOwner(&treeOwner);
  45
  46     // Make sure the tree owner is an an nsDocShellTreeOwner object
  47     // by QI'ing for a hidden interface. If it doesn't have the interface
  48     // then it's not safe to do the casting.
  49
  50     nsCOMPtr<nsICDocShellTreeOwner> realTreeOwner(do_QueryInterface(treeOwner));
  51     if (realTreeOwner)
  52     {
  53         nsDocShellTreeOwner *tree = static_cast<nsDocShellTreeOwner *>(treeOwner);
  54         if (tree->mTreeOwner)
  55         {
  56             nsresult rv;
  57             rv = tree->mTreeOwner->QueryInterface(NS_GET_IID(nsICommandHandler), (void **)aCommandHandler);
  58             NS_RELEASE(treeOwner);
  59             return rv;
  60         }
  61
  62         NS_RELEASE(treeOwner);
  63      }
  64
  65     *aCommandHandler = nullptr;
  66
  67     return NS_OK;
  68 }
  69
  70
  71 NS_IMPL_ADDREF(nsCommandHandler)
  72 NS_IMPL_RELEASE(nsCommandHandler)
  73
  74 NS_INTERFACE_MAP_BEGIN(nsCommandHandler)
  75     NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsICommandHandler)
  76     NS_INTERFACE_MAP_ENTRY(nsICommandHandlerInit)
  77     NS_INTERFACE_MAP_ENTRY(nsICommandHandler)
  78 NS_INTERFACE_MAP_END
  79
  80 ///////////////////////////////////////////////////////////////////////////////
  81 // nsICommandHandlerInit implementation
  82
  83 /* attribute nsIDocShell docShell; */
  84 NS_IMETHODIMP nsCommandHandler::GetWindow(nsIDOMWindow * *aWindow)
  85 {
  86     *aWindow = nullptr;
  87     return NS_OK;
  88 }
  89
  90 NS_IMETHODIMP nsCommandHandler::SetWindow(nsIDOMWindow * aWindow)
  91 {
  92     if (aWindow == nullptr)
  93     {
  94        return NS_ERROR_FAILURE;
  95     }
  96     mWindow = aWindow;
  97     return NS_OK;
  98 }
  99
 100 ///////////////////////////////////////////////////////////////////////////////
 101 // nsICommandHandler implementation
 102
 103 /* string exec (in string aCommand, in string aStatus); */
 104 NS_IMETHODIMP nsCommandHandler::Exec(const char *aCommand, const char *aStatus, char **aResult)
 105 {
 106     NS_ENSURE_ARG_POINTER(aCommand);
 107     NS_ENSURE_ARG_POINTER(aResult);
 108
 109     nsCOMPtr<nsICommandHandler> commandHandler;
 110     GetCommandHandler(getter_AddRefs(commandHandler));
 111
 112     // Call the client's command handler to deal with this command
 113     if (commandHandler)
 114     {
 115         *aResult = nullptr;
 116         return commandHandler->Exec(aCommand, aStatus, aResult);
 117     }
 118
 119     // Return an empty string
 120     const char szEmpty[] = "";
 121     *aResult = (char *) nsMemory::Clone(szEmpty, sizeof(szEmpty));
 122
 123     return NS_OK;
 124 }
 125
 126 /* string query (in string aCommand, in string aStatus); */
 127 NS_IMETHODIMP nsCommandHandler::Query(const char *aCommand, const char *aStatus, char **aResult)
 128 {
 129     NS_ENSURE_ARG_POINTER(aCommand);
 130     NS_ENSURE_ARG_POINTER(aResult);
 131
 132     nsCOMPtr<nsICommandHandler> commandHandler;
 133     GetCommandHandler(getter_AddRefs(commandHandler));
 134
 135     // Call the client's command handler to deal with this command
 136     if (commandHandler)
 137     {
 138         *aResult = nullptr;
 139         return commandHandler->Query(aCommand, aStatus, aResult);
 140     }
 141
 142     // Return an empty string
 143     const char szEmpty[] = "";
 144     *aResult = (char *) nsMemory::Clone(szEmpty, sizeof(szEmpty));
 145
 146     return NS_OK;
 147 }