gecko/content/base/src/nsNodeInfoManager.cpp

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/*
 * A class for handing out nodeinfos and ensuring sharing of them as needed.
 */

#include "nsNodeInfoManager.h"
#include "nsNodeInfo.h"
#include "nsCOMPtr.h"
#include "nsString.h"
#include "nsIAtom.h"
#include "nsIDocument.h"
#include "nsIPrincipal.h"
#include "nsIURI.h"
#include "nsContentUtils.h"
#include "nsReadableUtils.h"
#include "nsGkAtoms.h"
#include "nsComponentManagerUtils.h"
#include "nsLayoutStatics.h"
#include "nsBindingManager.h"

#ifdef MOZ_LOGGING
// so we can get logging even in release builds
#define FORCE_PR_LOG 1
#endif
#include "prlog.h"

#ifdef PR_LOGGING
static PRLogModuleInfo* gNodeInfoManagerLeakPRLog;
#endif

PLHashNumber
nsNodeInfoManager::GetNodeInfoInnerHashValue(const void *key)
{
  NS_ASSERTION(key, "Null key passed to nsNodeInfo::GetHashValue!");

  const nsINodeInfo::nsNodeInfoInner *node =
    reinterpret_cast<const nsINodeInfo::nsNodeInfoInner *>(key);

  // Is this an acceptable hash value?
  return (PLHashNumber(NS_PTR_TO_INT32(node->mName)) & 0xffff) >> 8;
}


PRIntn
nsNodeInfoManager::NodeInfoInnerKeyCompare(const void *key1, const void *key2)
{
  NS_ASSERTION(key1 && key2, "Null key passed to NodeInfoInnerKeyCompare!");

  const nsINodeInfo::nsNodeInfoInner *node1 =
    reinterpret_cast<const nsINodeInfo::nsNodeInfoInner *>(key1);
  const nsINodeInfo::nsNodeInfoInner *node2 =
    reinterpret_cast<const nsINodeInfo::nsNodeInfoInner *>(key2);

  return (node1->mName == node2->mName &&
          node1->mPrefix == node2->mPrefix &&
          node1->mNamespaceID == node2->mNamespaceID);
}


nsNodeInfoManager::nsNodeInfoManager()
  : mDocument(nsnull),
    mPrincipal(nsnull),
    mTextNodeInfo(nsnull),
    mCommentNodeInfo(nsnull),
    mDocumentNodeInfo(nsnull),
    mBindingManager(nsnull)
{
  nsLayoutStatics::AddRef();

#ifdef PR_LOGGING
  if (!gNodeInfoManagerLeakPRLog)
    gNodeInfoManagerLeakPRLog = PR_NewLogModule("NodeInfoManagerLeak");

  if (gNodeInfoManagerLeakPRLog)
    PR_LOG(gNodeInfoManagerLeakPRLog, PR_LOG_DEBUG,
           ("NODEINFOMANAGER %p created", this));
#endif

  mNodeInfoHash = PL_NewHashTable(32, GetNodeInfoInnerHashValue,
                                  NodeInfoInnerKeyCompare,
                                  PL_CompareValues, nsnull, nsnull);
}


nsNodeInfoManager::~nsNodeInfoManager()
{
  if (mNodeInfoHash)
    PL_HashTableDestroy(mNodeInfoHash);

  // Note: mPrincipal may be null here if we never got inited correctly
  NS_IF_RELEASE(mPrincipal);

  NS_IF_RELEASE(mBindingManager);

#ifdef PR_LOGGING
  if (gNodeInfoManagerLeakPRLog)
    PR_LOG(gNodeInfoManagerLeakPRLog, PR_LOG_DEBUG,
           ("NODEINFOMANAGER %p destroyed", this));
#endif

  nsLayoutStatics::Release();
}


nsrefcnt
nsNodeInfoManager::AddRef()
{
  NS_PRECONDITION(PRInt32(mRefCnt) >= 0, "illegal refcnt");

  nsrefcnt count = PR_AtomicIncrement((PRInt32*)&mRefCnt);
  NS_LOG_ADDREF(this, count, "nsNodeInfoManager", sizeof(*this));

  return count;
}

nsrefcnt
nsNodeInfoManager::Release()
{
  NS_PRECONDITION(0 != mRefCnt, "dup release");

  nsrefcnt count = PR_AtomicDecrement((PRInt32 *)&mRefCnt);
  NS_LOG_RELEASE(this, count, "nsNodeInfoManager");
  if (count == 0) {
    mRefCnt = 1; /* stabilize */
    delete this;
  }

  return count;
}

NS_IMPL_CYCLE_COLLECTION_CLASS(nsNodeInfoManager)
NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(nsNodeInfoManager, AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(nsNodeInfoManager, Release)
NS_IMPL_CYCLE_COLLECTION_UNLINK_NATIVE_0(nsNodeInfoManager)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NATIVE_BEGIN(nsNodeInfoManager)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE_RAWPTR(mBindingManager)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

nsresult
nsNodeInfoManager::Init(nsIDocument *aDocument)
{
  NS_ENSURE_TRUE(mNodeInfoHash, NS_ERROR_OUT_OF_MEMORY);

  NS_PRECONDITION(!mPrincipal,
                  "Being inited when we already have a principal?");
  nsresult rv = CallCreateInstance("@mozilla.org/nullprincipal;1",
                                   &mPrincipal);
  NS_ENSURE_TRUE(mPrincipal, rv);

  if (aDocument) {
    mBindingManager = new nsBindingManager(aDocument);
    NS_ENSURE_TRUE(mBindingManager, NS_ERROR_OUT_OF_MEMORY);

    NS_ADDREF(mBindingManager);
  }

  mDefaultPrincipal = mPrincipal;

  mDocument = aDocument;

#ifdef PR_LOGGING
  if (gNodeInfoManagerLeakPRLog)
    PR_LOG(gNodeInfoManagerLeakPRLog, PR_LOG_DEBUG,
           ("NODEINFOMANAGER %p Init document=%p", this, aDocument));
#endif

  return NS_OK;
}

void
nsNodeInfoManager::DropDocumentReference()
{
  if (mBindingManager) {
    mBindingManager->DropDocumentReference();
  }

  mDocument = nsnull;
}


already_AddRefed<nsINodeInfo>
nsNodeInfoManager::GetNodeInfo(nsIAtom *aName, nsIAtom *aPrefix,
                               PRInt32 aNamespaceID)
{
  NS_ENSURE_TRUE(aName, nsnull);
  NS_ASSERTION(!aName->Equals(EmptyString()),
               "Don't pass an empty string to GetNodeInfo, fix caller.");

  nsINodeInfo::nsNodeInfoInner tmpKey(aName, aPrefix, aNamespaceID);

  void *node = PL_HashTableLookup(mNodeInfoHash, &tmpKey);

  if (node) {
    nsINodeInfo* nodeInfo = static_cast<nsINodeInfo *>(node);

    NS_ADDREF(nodeInfo);

    return nodeInfo;
  }

  nsRefPtr<nsNodeInfo> newNodeInfo = nsNodeInfo::Create();
  NS_ENSURE_TRUE(newNodeInfo, nsnull);
  
  nsresult rv = newNodeInfo->Init(aName, aPrefix, aNamespaceID, this);
  NS_ENSURE_SUCCESS(rv, nsnull);

  PLHashEntry *he;
  he = PL_HashTableAdd(mNodeInfoHash, &newNodeInfo->mInner, newNodeInfo);
  NS_ENSURE_TRUE(he, nsnull);

  nsNodeInfo *nodeInfo = nsnull;
  newNodeInfo.swap(nodeInfo);

  return nodeInfo;
}


nsresult
nsNodeInfoManager::GetNodeInfo(const nsAString& aName, nsIAtom *aPrefix,
                               PRInt32 aNamespaceID, nsINodeInfo** aNodeInfo)
{
  nsCOMPtr<nsIAtom> name = do_GetAtom(aName);
  *aNodeInfo = nsNodeInfoManager::GetNodeInfo(name, aPrefix, aNamespaceID).get();
  return *aNodeInfo ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
}


nsresult
nsNodeInfoManager::GetNodeInfo(const nsAString& aName, nsIAtom *aPrefix,
                               const nsAString& aNamespaceURI,
                               nsINodeInfo** aNodeInfo)
{
  nsCOMPtr<nsIAtom> nameAtom = do_GetAtom(aName);
  NS_ENSURE_TRUE(nameAtom, NS_ERROR_OUT_OF_MEMORY);

  PRInt32 nsid = kNameSpaceID_None;

  if (!aNamespaceURI.IsEmpty()) {
    nsresult rv = nsContentUtils::NameSpaceManager()->
      RegisterNameSpace(aNamespaceURI, nsid);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  *aNodeInfo = GetNodeInfo(nameAtom, aPrefix, nsid).get();
  return *aNodeInfo ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
}

already_AddRefed<nsINodeInfo>
nsNodeInfoManager::GetTextNodeInfo()
{
  if (!mTextNodeInfo) {
    mTextNodeInfo = GetNodeInfo(nsGkAtoms::textTagName, nsnull, kNameSpaceID_None).get();
  }
  else {
    NS_ADDREF(mTextNodeInfo);
  }

  return mTextNodeInfo;
}

already_AddRefed<nsINodeInfo>
nsNodeInfoManager::GetCommentNodeInfo()
{
  if (!mCommentNodeInfo) {
    mCommentNodeInfo = GetNodeInfo(nsGkAtoms::commentTagName, nsnull, kNameSpaceID_None).get();
  }
  else {
    NS_ADDREF(mCommentNodeInfo);
  }

  return mCommentNodeInfo;
}

already_AddRefed<nsINodeInfo>
nsNodeInfoManager::GetDocumentNodeInfo()
{
  if (!mDocumentNodeInfo) {
    mDocumentNodeInfo = GetNodeInfo(nsGkAtoms::documentNodeName, nsnull, kNameSpaceID_None).get();
  }
  else {
    NS_ADDREF(mDocumentNodeInfo);
  }

  return mDocumentNodeInfo;
}

void
nsNodeInfoManager::SetDocumentPrincipal(nsIPrincipal *aPrincipal)
{
  NS_RELEASE(mPrincipal);
  if (!aPrincipal) {
    aPrincipal = mDefaultPrincipal;
  }

  NS_ASSERTION(aPrincipal, "Must have principal by this point!");
  
  NS_ADDREF(mPrincipal = aPrincipal);
}

void
nsNodeInfoManager::RemoveNodeInfo(nsNodeInfo *aNodeInfo)
{
  NS_PRECONDITION(aNodeInfo, "Trying to remove null nodeinfo from manager!");

  // Drop weak reference if needed
  if (aNodeInfo == mTextNodeInfo) {
    mTextNodeInfo = nsnull;
  }
  else if (aNodeInfo == mCommentNodeInfo) {
    mCommentNodeInfo = nsnull;
  }
  else if (aNodeInfo == mDocumentNodeInfo) {
    mDocumentNodeInfo = nsnull;
  }

#ifdef DEBUG
  PRBool ret =
#endif
  PL_HashTableRemove(mNodeInfoHash, &aNodeInfo->mInner);

  NS_POSTCONDITION(ret, "Can't find nsINodeInfo to remove!!!");
}