docshell/base/nsDocShellEnumerator.cpp

   1 /* -*- Mode: C++; tab-width: 2; 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
   8 #include "nsDocShellEnumerator.h"
   9
  10 #include "nsIDocShellTreeItem.h"
  11
  12 nsDocShellEnumerator::nsDocShellEnumerator(int32_t inEnumerationDirection)
  13 : mRootItem(nullptr)
  14 , mCurIndex(0)
  15 , mDocShellType(nsIDocShellTreeItem::typeAll)
  16 , mArrayValid(false)
  17 , mEnumerationDirection(inEnumerationDirection)
  18 {
  19 }
  20
  21 nsDocShellEnumerator::~nsDocShellEnumerator()
  22 {
  23 }
  24
  25 NS_IMPL_ISUPPORTS(nsDocShellEnumerator, nsISimpleEnumerator)
  26
  27
  28 /* nsISupports getNext (); */
  29 NS_IMETHODIMP nsDocShellEnumerator::GetNext(nsISupports **outCurItem)
  30 {
  31   NS_ENSURE_ARG_POINTER(outCurItem);
  32   *outCurItem = nullptr;
  33
  34   nsresult rv = EnsureDocShellArray();
  35   if (NS_FAILED(rv)) return rv;
  36
  37   if (mCurIndex >= mItemArray.Length()) {
  38     return NS_ERROR_FAILURE;
  39   }
  40
  41   // post-increment is important here
  42   nsCOMPtr<nsISupports> item = do_QueryReferent(mItemArray[mCurIndex++], &rv);
  43   item.forget(outCurItem);
  44   return rv;
  45 }
  46
  47 /* boolean hasMoreElements (); */
  48 NS_IMETHODIMP nsDocShellEnumerator::HasMoreElements(bool *outHasMore)
  49 {
  50   NS_ENSURE_ARG_POINTER(outHasMore);
  51   *outHasMore = false;
  52
  53   nsresult rv = EnsureDocShellArray();
  54   if (NS_FAILED(rv)) return rv;
  55
  56   *outHasMore = (mCurIndex < mItemArray.Length());
  57   return NS_OK;
  58 }
  59
  60 nsresult nsDocShellEnumerator::GetEnumerationRootItem(nsIDocShellTreeItem * *aEnumerationRootItem)
  61 {
  62   NS_ENSURE_ARG_POINTER(aEnumerationRootItem);
  63   nsCOMPtr<nsIDocShellTreeItem> item = do_QueryReferent(mRootItem);
  64   item.forget(aEnumerationRootItem);
  65   return NS_OK;
  66 }
  67
  68 nsresult nsDocShellEnumerator::SetEnumerationRootItem(nsIDocShellTreeItem * aEnumerationRootItem)
  69 {
  70   mRootItem = do_GetWeakReference(aEnumerationRootItem);
  71   ClearState();
  72   return NS_OK;
  73 }
  74
  75 nsresult nsDocShellEnumerator::GetEnumDocShellType(int32_t *aEnumerationItemType)
  76 {
  77   NS_ENSURE_ARG_POINTER(aEnumerationItemType);
  78   *aEnumerationItemType = mDocShellType;
  79   return NS_OK;
  80 }
  81
  82 nsresult nsDocShellEnumerator::SetEnumDocShellType(int32_t aEnumerationItemType)
  83 {
  84   mDocShellType = aEnumerationItemType;
  85   ClearState();
  86   return NS_OK;
  87 }
  88
  89 nsresult nsDocShellEnumerator::First()
  90 {
  91   mCurIndex = 0;
  92   return EnsureDocShellArray();
  93 }
  94
  95 nsresult nsDocShellEnumerator::EnsureDocShellArray()
  96 {
  97   if (!mArrayValid)
  98   {
  99     mArrayValid = true;
 100     return BuildDocShellArray(mItemArray);
 101   }
 102
 103   return NS_OK;
 104 }
 105
 106 nsresult nsDocShellEnumerator::ClearState()
 107 {
 108   mItemArray.Clear();
 109   mArrayValid = false;
 110   mCurIndex = 0;
 111   return NS_OK;
 112 }
 113
 114 nsresult nsDocShellEnumerator::BuildDocShellArray(nsTArray<nsWeakPtr>& inItemArray)
 115 {
 116   NS_ENSURE_TRUE(mRootItem, NS_ERROR_NOT_INITIALIZED);
 117   inItemArray.Clear();
 118   nsCOMPtr<nsIDocShellTreeItem> item = do_QueryReferent(mRootItem);
 119   return BuildArrayRecursive(item, inItemArray);
 120 }
 121
 122 nsresult nsDocShellForwardsEnumerator::BuildArrayRecursive(nsIDocShellTreeItem* inItem, nsTArray<nsWeakPtr>& inItemArray)
 123 {
 124   nsresult rv;
 125
 126   // add this item to the array
 127   if (mDocShellType == nsIDocShellTreeItem::typeAll ||
 128       inItem->ItemType() == mDocShellType) {
 129     nsWeakPtr weakItem = do_GetWeakReference(inItem);
 130     if (!inItemArray.AppendElement(weakItem))
 131       return NS_ERROR_OUT_OF_MEMORY;
 132   }
 133
 134   int32_t   numChildren;
 135   rv = inItem->GetChildCount(&numChildren);
 136   if (NS_FAILED(rv)) return rv;
 137
 138   for (int32_t i = 0; i < numChildren; ++i)
 139   {
 140     nsCOMPtr<nsIDocShellTreeItem> curChild;
 141     rv = inItem->GetChildAt(i, getter_AddRefs(curChild));
 142     if (NS_FAILED(rv)) return rv;
 143
 144     rv = BuildArrayRecursive(curChild, inItemArray);
 145     if (NS_FAILED(rv)) return rv;
 146   }
 147
 148   return NS_OK;
 149 }
 150
 151
 152 nsresult nsDocShellBackwardsEnumerator::BuildArrayRecursive(nsIDocShellTreeItem* inItem, nsTArray<nsWeakPtr>& inItemArray)
 153 {
 154   nsresult rv;
 155
 156   int32_t   numChildren;
 157   rv = inItem->GetChildCount(&numChildren);
 158   if (NS_FAILED(rv)) return rv;
 159
 160   for (int32_t i = numChildren - 1; i >= 0; --i)
 161   {
 162     nsCOMPtr<nsIDocShellTreeItem> curChild;
 163     rv = inItem->GetChildAt(i, getter_AddRefs(curChild));
 164     if (NS_FAILED(rv)) return rv;
 165
 166     rv = BuildArrayRecursive(curChild, inItemArray);
 167     if (NS_FAILED(rv)) return rv;
 168   }
 169
 170   // add this item to the array
 171   if (mDocShellType == nsIDocShellTreeItem::typeAll ||
 172       inItem->ItemType() == mDocShellType) {
 173     nsWeakPtr weakItem = do_GetWeakReference(inItem);
 174     if (!inItemArray.AppendElement(weakItem))
 175       return NS_ERROR_OUT_OF_MEMORY;
 176   }
 177
 178   return NS_OK;
 179 }