gecko/layout/base/nsStyleSheetService.cpp
2012-07-30 17:20:58 +03:00

186 lines
5.7 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* implementation of interface for managing user and user-agent style sheets */
#include "prlog.h"
#include "nsStyleSheetService.h"
#include "nsIStyleSheet.h"
#include "mozilla/css/Loader.h"
#include "nsCSSStyleSheet.h"
#include "nsIURI.h"
#include "nsContentCID.h"
#include "nsCOMPtr.h"
#include "nsIServiceManager.h"
#include "nsICategoryManager.h"
#include "nsISupportsPrimitives.h"
#include "nsNetUtil.h"
#include "nsIObserverService.h"
#include "nsLayoutStatics.h"
nsStyleSheetService *nsStyleSheetService::gInstance = nullptr;
nsStyleSheetService::nsStyleSheetService()
{
PR_STATIC_ASSERT(0 == AGENT_SHEET && 1 == USER_SHEET);
NS_ASSERTION(!gInstance, "Someone is using CreateInstance instead of GetService");
gInstance = this;
nsLayoutStatics::AddRef();
}
nsStyleSheetService::~nsStyleSheetService()
{
gInstance = nullptr;
nsLayoutStatics::Release();
}
NS_IMPL_ISUPPORTS1(nsStyleSheetService, nsIStyleSheetService)
void
nsStyleSheetService::RegisterFromEnumerator(nsICategoryManager *aManager,
const char *aCategory,
nsISimpleEnumerator *aEnumerator,
PRUint32 aSheetType)
{
if (!aEnumerator)
return;
bool hasMore;
while (NS_SUCCEEDED(aEnumerator->HasMoreElements(&hasMore)) && hasMore) {
nsCOMPtr<nsISupports> element;
if (NS_FAILED(aEnumerator->GetNext(getter_AddRefs(element))))
break;
nsCOMPtr<nsISupportsCString> icStr = do_QueryInterface(element);
NS_ASSERTION(icStr,
"category manager entries must be nsISupportsCStrings");
nsCAutoString name;
icStr->GetData(name);
nsXPIDLCString spec;
aManager->GetCategoryEntry(aCategory, name.get(), getter_Copies(spec));
nsCOMPtr<nsIURI> uri;
NS_NewURI(getter_AddRefs(uri), spec);
if (uri)
LoadAndRegisterSheetInternal(uri, aSheetType);
}
}
PRInt32
nsStyleSheetService::FindSheetByURI(const nsCOMArray<nsIStyleSheet> &sheets,
nsIURI *sheetURI)
{
for (PRInt32 i = sheets.Count() - 1; i >= 0; i-- ) {
bool bEqual;
nsIURI* uri = sheets[i]->GetSheetURI();
if (uri
&& NS_SUCCEEDED(uri->Equals(sheetURI, &bEqual))
&& bEqual) {
return i;
}
}
return -1;
}
nsresult
nsStyleSheetService::Init()
{
// Enumerate all of the style sheet URIs registered in the category
// manager and load them.
nsCOMPtr<nsICategoryManager> catMan =
do_GetService(NS_CATEGORYMANAGER_CONTRACTID);
NS_ENSURE_TRUE(catMan, NS_ERROR_OUT_OF_MEMORY);
nsCOMPtr<nsISimpleEnumerator> sheets;
catMan->EnumerateCategory("agent-style-sheets", getter_AddRefs(sheets));
RegisterFromEnumerator(catMan, "agent-style-sheets", sheets, AGENT_SHEET);
catMan->EnumerateCategory("user-style-sheets", getter_AddRefs(sheets));
RegisterFromEnumerator(catMan, "user-style-sheets", sheets, USER_SHEET);
return NS_OK;
}
NS_IMETHODIMP
nsStyleSheetService::LoadAndRegisterSheet(nsIURI *aSheetURI,
PRUint32 aSheetType)
{
nsresult rv = LoadAndRegisterSheetInternal(aSheetURI, aSheetType);
if (NS_SUCCEEDED(rv)) {
const char* message = (aSheetType == AGENT_SHEET) ?
"agent-sheet-added" : "user-sheet-added";
nsCOMPtr<nsIObserverService> serv =
mozilla::services::GetObserverService();
if (serv) {
// We're guaranteed that the new sheet is the last sheet in
// mSheets[aSheetType]
const nsCOMArray<nsIStyleSheet> & sheets = mSheets[aSheetType];
serv->NotifyObservers(sheets[sheets.Count() - 1], message, nullptr);
}
}
return rv;
}
nsresult
nsStyleSheetService::LoadAndRegisterSheetInternal(nsIURI *aSheetURI,
PRUint32 aSheetType)
{
NS_ENSURE_ARG(aSheetType == AGENT_SHEET || aSheetType == USER_SHEET);
NS_ENSURE_ARG_POINTER(aSheetURI);
nsRefPtr<mozilla::css::Loader> loader = new mozilla::css::Loader();
nsRefPtr<nsCSSStyleSheet> sheet;
// Allow UA sheets, but not user sheets, to use unsafe rules
nsresult rv = loader->LoadSheetSync(aSheetURI, aSheetType == AGENT_SHEET,
true, getter_AddRefs(sheet));
NS_ENSURE_SUCCESS(rv, rv);
if (!mSheets[aSheetType].AppendObject(sheet)) {
rv = NS_ERROR_OUT_OF_MEMORY;
}
return rv;
}
NS_IMETHODIMP
nsStyleSheetService::SheetRegistered(nsIURI *sheetURI,
PRUint32 aSheetType, bool *_retval)
{
NS_ENSURE_ARG(aSheetType == AGENT_SHEET || aSheetType == USER_SHEET);
NS_ENSURE_ARG_POINTER(sheetURI);
NS_PRECONDITION(_retval, "Null out param");
*_retval = (FindSheetByURI(mSheets[aSheetType], sheetURI) >= 0);
return NS_OK;
}
NS_IMETHODIMP
nsStyleSheetService::UnregisterSheet(nsIURI *sheetURI, PRUint32 aSheetType)
{
NS_ENSURE_ARG(aSheetType == AGENT_SHEET || aSheetType == USER_SHEET);
NS_ENSURE_ARG_POINTER(sheetURI);
PRInt32 foundIndex = FindSheetByURI(mSheets[aSheetType], sheetURI);
NS_ENSURE_TRUE(foundIndex >= 0, NS_ERROR_INVALID_ARG);
nsCOMPtr<nsIStyleSheet> sheet = mSheets[aSheetType][foundIndex];
mSheets[aSheetType].RemoveObjectAt(foundIndex);
const char* message = (aSheetType == AGENT_SHEET) ?
"agent-sheet-removed" : "user-sheet-removed";
nsCOMPtr<nsIObserverService> serv =
mozilla::services::GetObserverService();
if (serv)
serv->NotifyObservers(sheet, message, nullptr);
return NS_OK;
}