gecko/xpcom/glue/nsCategoryCache.cpp

186 lines
6.1 KiB
C++

/* vim:set st=2 sts=2 ts=2 et cin: */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is a cache for services in a category.
*
* The Initial Developer of the Original Code is
* Christian Biesinger <cbiesinger@web.de>.
* Portions created by the Initial Developer are Copyright (C) 2005
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsIObserverService.h"
#include "nsISupportsPrimitives.h"
#include "nsXPCOMCID.h"
#include "nsCategoryCache.h"
nsCategoryObserver::nsCategoryObserver(const char* aCategory,
nsCategoryListener* aListener)
: mListener(nsnull), mCategory(aCategory), mObserversRemoved(false)
{
if (!mHash.Init()) {
// OOM
return;
}
mListener = aListener;
// First, enumerate the currently existing entries
nsCOMPtr<nsICategoryManager> catMan =
do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
if (!catMan)
return;
nsCOMPtr<nsISimpleEnumerator> enumerator;
nsresult rv = catMan->EnumerateCategory(aCategory,
getter_AddRefs(enumerator));
if (NS_FAILED(rv))
return;
nsTArray<nsCString> entries;
nsCOMPtr<nsISupports> entry;
while (NS_SUCCEEDED(enumerator->GetNext(getter_AddRefs(entry)))) {
nsCOMPtr<nsISupportsCString> entryName = do_QueryInterface(entry, &rv);
if (NS_SUCCEEDED(rv)) {
nsCAutoString categoryEntry;
rv = entryName->GetData(categoryEntry);
nsCString entryValue;
catMan->GetCategoryEntry(aCategory,
categoryEntry.get(),
getter_Copies(entryValue));
if (NS_SUCCEEDED(rv)) {
mHash.Put(categoryEntry, entryValue);
entries.AppendElement(entryValue);
}
}
}
// Now, listen for changes
nsCOMPtr<nsIObserverService> serv =
do_GetService(NS_OBSERVERSERVICE_CONTRACTID);
if (serv) {
serv->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, PR_FALSE);
serv->AddObserver(this, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID, PR_FALSE);
serv->AddObserver(this, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID, PR_FALSE);
serv->AddObserver(this, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID, PR_FALSE);
}
for (PRInt32 i = entries.Length() - 1; i >= 0; --i)
mListener->EntryAdded(entries[i]);
}
nsCategoryObserver::~nsCategoryObserver() {
}
NS_IMPL_ISUPPORTS1(nsCategoryObserver, nsIObserver)
void
nsCategoryObserver::ListenerDied() {
mListener = nsnull;
RemoveObservers();
}
NS_HIDDEN_(void)
nsCategoryObserver::RemoveObservers() {
if (mObserversRemoved)
return;
mObserversRemoved = true;
nsCOMPtr<nsIObserverService> obsSvc =
do_GetService(NS_OBSERVERSERVICE_CONTRACTID);
if (obsSvc) {
obsSvc->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID);
obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID);
obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID);
obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID);
}
}
NS_IMETHODIMP
nsCategoryObserver::Observe(nsISupports* aSubject, const char* aTopic,
const PRUnichar* aData) {
if (!mListener)
return NS_OK;
if (strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) {
mHash.Clear();
mListener->CategoryCleared();
RemoveObservers();
return NS_OK;
}
if (!aData ||
!nsDependentString(aData).Equals(NS_ConvertASCIItoUTF16(mCategory)))
return NS_OK;
nsCAutoString str;
nsCOMPtr<nsISupportsCString> strWrapper(do_QueryInterface(aSubject));
if (strWrapper)
strWrapper->GetData(str);
if (strcmp(aTopic, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID) == 0) {
// We may get an add notification even when we already have an entry. This
// is due to the notification happening asynchronously, so if the entry gets
// added and an nsCategoryObserver gets instantiated before events get
// processed, we'd get the notification for an existing entry.
// Do nothing in that case.
if (mHash.Get(str, nsnull))
return NS_OK;
nsCOMPtr<nsICategoryManager> catMan =
do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
if (!catMan)
return NS_OK;
nsCString entryValue;
catMan->GetCategoryEntry(mCategory.get(),
str.get(),
getter_Copies(entryValue));
mHash.Put(str, entryValue);
mListener->EntryAdded(entryValue);
} else if (strcmp(aTopic, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID) == 0) {
nsCAutoString val;
if (mHash.Get(str, &val)) {
mHash.Remove(str);
mListener->EntryRemoved(val);
}
} else if (strcmp(aTopic, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID) == 0) {
mHash.Clear();
mListener->CategoryCleared();
}
return NS_OK;
}