1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/xpcom/glue/nsCategoryCache.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,137 @@
1.4 +/* vim:set st=2 sts=2 ts=2 et cin: */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include "nsIObserverService.h"
1.10 +#include "mozilla/Services.h"
1.11 +#include "nsISupportsPrimitives.h"
1.12 +#include "nsIStringEnumerator.h"
1.13 +
1.14 +#include "nsXPCOMCID.h"
1.15 +
1.16 +#include "nsCategoryCache.h"
1.17 +
1.18 +nsCategoryObserver::nsCategoryObserver(const char* aCategory)
1.19 + : mCategory(aCategory)
1.20 + , mObserversRemoved(false)
1.21 +{
1.22 + // First, enumerate the currently existing entries
1.23 + nsCOMPtr<nsICategoryManager> catMan =
1.24 + do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
1.25 + if (!catMan)
1.26 + return;
1.27 +
1.28 + nsCOMPtr<nsISimpleEnumerator> enumerator;
1.29 + nsresult rv = catMan->EnumerateCategory(aCategory,
1.30 + getter_AddRefs(enumerator));
1.31 + if (NS_FAILED(rv))
1.32 + return;
1.33 +
1.34 + nsCOMPtr<nsIUTF8StringEnumerator> strings = do_QueryInterface(enumerator);
1.35 + MOZ_ASSERT(strings);
1.36 +
1.37 + bool more;
1.38 + while (NS_SUCCEEDED(strings->HasMore(&more)) && more) {
1.39 + nsAutoCString entryName;
1.40 + strings->GetNext(entryName);
1.41 +
1.42 + nsCString entryValue;
1.43 + rv = catMan->GetCategoryEntry(aCategory,
1.44 + entryName.get(),
1.45 + getter_Copies(entryValue));
1.46 + if (NS_SUCCEEDED(rv)) {
1.47 + nsCOMPtr<nsISupports> service = do_GetService(entryValue.get());
1.48 + if (service) {
1.49 + mHash.Put(entryName, service);
1.50 + }
1.51 + }
1.52 + }
1.53 +
1.54 + // Now, listen for changes
1.55 + nsCOMPtr<nsIObserverService> serv =
1.56 + mozilla::services::GetObserverService();
1.57 + if (serv) {
1.58 + serv->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
1.59 + serv->AddObserver(this, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID, false);
1.60 + serv->AddObserver(this, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID, false);
1.61 + serv->AddObserver(this, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID, false);
1.62 + }
1.63 +}
1.64 +
1.65 +nsCategoryObserver::~nsCategoryObserver() {
1.66 +}
1.67 +
1.68 +NS_IMPL_ISUPPORTS(nsCategoryObserver, nsIObserver)
1.69 +
1.70 +void
1.71 +nsCategoryObserver::ListenerDied() {
1.72 + RemoveObservers();
1.73 +}
1.74 +
1.75 +void
1.76 +nsCategoryObserver::RemoveObservers() {
1.77 + if (mObserversRemoved)
1.78 + return;
1.79 +
1.80 + mObserversRemoved = true;
1.81 + nsCOMPtr<nsIObserverService> obsSvc =
1.82 + mozilla::services::GetObserverService();
1.83 + if (obsSvc) {
1.84 + obsSvc->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID);
1.85 + obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID);
1.86 + obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID);
1.87 + obsSvc->RemoveObserver(this, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID);
1.88 + }
1.89 +}
1.90 +
1.91 +NS_IMETHODIMP
1.92 +nsCategoryObserver::Observe(nsISupports* aSubject, const char* aTopic,
1.93 + const char16_t* aData) {
1.94 + if (strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) {
1.95 + mHash.Clear();
1.96 + RemoveObservers();
1.97 +
1.98 + return NS_OK;
1.99 + }
1.100 +
1.101 + if (!aData ||
1.102 + !nsDependentString(aData).Equals(NS_ConvertASCIItoUTF16(mCategory)))
1.103 + return NS_OK;
1.104 +
1.105 + nsAutoCString str;
1.106 + nsCOMPtr<nsISupportsCString> strWrapper(do_QueryInterface(aSubject));
1.107 + if (strWrapper)
1.108 + strWrapper->GetData(str);
1.109 +
1.110 + if (strcmp(aTopic, NS_XPCOM_CATEGORY_ENTRY_ADDED_OBSERVER_ID) == 0) {
1.111 + // We may get an add notification even when we already have an entry. This
1.112 + // is due to the notification happening asynchronously, so if the entry gets
1.113 + // added and an nsCategoryObserver gets instantiated before events get
1.114 + // processed, we'd get the notification for an existing entry.
1.115 + // Do nothing in that case.
1.116 + if (mHash.GetWeak(str))
1.117 + return NS_OK;
1.118 +
1.119 + nsCOMPtr<nsICategoryManager> catMan =
1.120 + do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
1.121 + if (!catMan)
1.122 + return NS_OK;
1.123 +
1.124 + nsCString entryValue;
1.125 + catMan->GetCategoryEntry(mCategory.get(),
1.126 + str.get(),
1.127 + getter_Copies(entryValue));
1.128 +
1.129 + nsCOMPtr<nsISupports> service = do_GetService(entryValue.get());
1.130 +
1.131 + if (service) {
1.132 + mHash.Put(str, service);
1.133 + }
1.134 + } else if (strcmp(aTopic, NS_XPCOM_CATEGORY_ENTRY_REMOVED_OBSERVER_ID) == 0) {
1.135 + mHash.Remove(str);
1.136 + } else if (strcmp(aTopic, NS_XPCOM_CATEGORY_CLEARED_OBSERVER_ID) == 0) {
1.137 + mHash.Clear();
1.138 + }
1.139 + return NS_OK;
1.140 +}
