michael@0: /* vim:set st=2 sts=2 ts=2 et cin: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsIObserverService.h"
michael@0: #include "mozilla/Services.h"
michael@0: #include "nsISupportsPrimitives.h"
michael@0: #include "nsIStringEnumerator.h"
michael@0: 
michael@0: #include "nsXPCOMCID.h"
michael@0: 
michael@0: #include "nsCategoryCache.h"
michael@0: 
michael@0: nsCategoryObserver::nsCategoryObserver(const char* aCategory)
michael@0:   : mCategory(aCategory)
michael@0:   , mObserversRemoved(false)
michael@0: {
michael@0:   // First, enumerate the currently existing entries
michael@0:   nsCOMPtr<nsICategoryManager> catMan =
michael@0:     do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
michael@0:   if (!catMan)
michael@0:     return;
michael@0: 
michael@0:   nsCOMPtr<nsISimpleEnumerator> enumerator;
michael@0:   nsresult rv = catMan->EnumerateCategory(aCategory,
michael@0:                                           getter_AddRefs(enumerator));
michael@0:   if (NS_FAILED(rv))
michael@0:     return;
michael@0: 
michael@0:   nsCOMPtr<nsIUTF8StringEnumerator> strings = do_QueryInterface(enumerator);
michael@0:   MOZ_ASSERT(strings);
michael@0: 
michael@0:   bool more;
michael@0:   while (NS_SUCCEEDED(strings->HasMore(&more)) && more) {
michael@0:     nsAutoCString entryName;
michael@0:     strings->GetNext(entryName);
michael@0: 
michael@0:     nsCString entryValue;
michael@0:     rv = catMan->GetCategoryEntry(aCategory,
michael@0: 				  entryName.get(),
michael@0: 				  getter_Copies(entryValue));
michael@0:     if (NS_SUCCEEDED(rv)) {
michael@0:       nsCOMPtr<nsISupports> service = do_GetService(entryValue.get());
michael@0:       if (service) {
michael@0: 	mHash.Put(entryName, service);
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // Now, listen for changes
michael@0:   nsCOMPtr<nsIObserverService> serv =
michael@0:     mozilla::services::GetObserverService();
michael@0:   if (serv) {
michael@0:     serv->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
michael@0:     serv->AddObserver(this, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID, false);
michael@0:     serv->AddObserver(this, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID, false);
michael@0:     serv->AddObserver(this, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID, false);
michael@0:   }
michael@0: }
michael@0: 
michael@0: nsCategoryObserver::~nsCategoryObserver() {
michael@0: }
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(nsCategoryObserver, nsIObserver)
michael@0: 
michael@0: void
michael@0: nsCategoryObserver::ListenerDied() {
michael@0:   RemoveObservers();
michael@0: }
michael@0: 
michael@0: void
michael@0: nsCategoryObserver::RemoveObservers() {
michael@0:   if (mObserversRemoved)
michael@0:     return;
michael@0: 
michael@0:   mObserversRemoved = true;
michael@0:   nsCOMPtr<nsIObserverService> obsSvc =
michael@0:     mozilla::services::GetObserverService();
michael@0:   if (obsSvc) {
michael@0:     obsSvc->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID);
michael@0:     obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID);
michael@0:     obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID);
michael@0:     obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID);
michael@0:   }
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsCategoryObserver::Observe(nsISupports* aSubject, const char* aTopic,
michael@0:                             const char16_t* aData) {
michael@0:   if (strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) {
michael@0:     mHash.Clear();
michael@0:     RemoveObservers();
michael@0: 
michael@0:     return NS_OK;
michael@0:   }
michael@0: 
michael@0:   if (!aData ||
michael@0:       !nsDependentString(aData).Equals(NS_ConvertASCIItoUTF16(mCategory)))
michael@0:     return NS_OK;
michael@0: 
michael@0:   nsAutoCString str;
michael@0:   nsCOMPtr<nsISupportsCString> strWrapper(do_QueryInterface(aSubject));
michael@0:   if (strWrapper)
michael@0:     strWrapper->GetData(str);
michael@0: 
michael@0:   if (strcmp(aTopic, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID) == 0) {
michael@0:     // We may get an add notification even when we already have an entry. This
michael@0:     // is due to the notification happening asynchronously, so if the entry gets
michael@0:     // added and an nsCategoryObserver gets instantiated before events get
michael@0:     // processed, we'd get the notification for an existing entry.
michael@0:     // Do nothing in that case.
michael@0:     if (mHash.GetWeak(str))
michael@0:       return NS_OK;
michael@0: 
michael@0:     nsCOMPtr<nsICategoryManager> catMan =
michael@0:       do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
michael@0:     if (!catMan)
michael@0:       return NS_OK;
michael@0: 
michael@0:     nsCString entryValue;
michael@0:     catMan->GetCategoryEntry(mCategory.get(),
michael@0:                              str.get(),
michael@0:                              getter_Copies(entryValue));
michael@0: 
michael@0:     nsCOMPtr<nsISupports> service = do_GetService(entryValue.get());
michael@0: 
michael@0:     if (service) {
michael@0:       mHash.Put(str, service);
michael@0:     }
michael@0:   } else if (strcmp(aTopic, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID) == 0) {
michael@0:     mHash.Remove(str);
michael@0:   } else if (strcmp(aTopic, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID) == 0) {
michael@0:     mHash.Clear();
michael@0:   }
michael@0:   return NS_OK;
michael@0: }