gecko-dev/layout/style/nsICSSLoader.h

287 lines
12 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** 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 mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of 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 ***** */
/* loading of CSS style sheets using the network APIs */
#ifndef nsICSSLoader_h___
#define nsICSSLoader_h___
#include "nsISupports.h"
#include "nsSubstring.h"
#include "nsCompatibility.h"
class nsIAtom;
class nsIURI;
class nsICSSParser;
class nsICSSStyleSheet;
class nsPresContext;
class nsIContent;
class nsIDocument;
class nsIUnicharInputStream;
class nsICSSLoaderObserver;
class nsMediaList;
class nsICSSImportRule;
class nsIPrincipal;
// IID for the nsICSSLoader interface
// 0c6d7e76-dddc-4727-b557-7ef531127e11
#define NS_ICSS_LOADER_IID \
{ 0x0c6d7e76, 0xdddc, 0x4727, \
{ 0xb5, 0x57, 0x7e, 0xf5, 0x31, 0x12, 0x7e, 0x11 } }
typedef void (*nsCSSLoaderCallbackFunc)(nsICSSStyleSheet* aSheet, void *aData, PRBool aDidNotify);
class nsICSSLoader : public nsISupports {
public:
NS_DECLARE_STATIC_IID_ACCESSOR(NS_ICSS_LOADER_IID)
NS_IMETHOD Init(nsIDocument* aDocument) = 0;
NS_IMETHOD DropDocumentReference(void) = 0; // notification that doc is going away
NS_IMETHOD SetCaseSensitive(PRBool aCaseSensitive) = 0;
NS_IMETHOD SetCompatibilityMode(nsCompatibility aCompatMode) = 0;
NS_IMETHOD SetPreferredSheet(const nsAString& aTitle) = 0;
NS_IMETHOD GetPreferredSheet(nsAString& aTitle) = 0;
// Get/Recycle a CSS parser for general use
NS_IMETHOD GetParserFor(nsICSSStyleSheet* aSheet,
nsICSSParser** aParser) = 0;
NS_IMETHOD RecycleParser(nsICSSParser* aParser) = 0;
// XXXbz sort out what the deal is with events! When should they fire?
/**
* Load an inline style sheet. If a successful result is returned and
* *aCompleted is false, then aObserver is guaranteed to be notified
* asynchronously once the sheet is marked complete. If an error is
* returned, or if *aCompleted is true, aObserver will not be notified. In
* addition to parsing the sheet, this method will insert it into the
* stylesheet list of this CSSLoader's document.
*
* @param aElement the element linking to the stylesheet. This must not be
* null and must implement nsIStyleSheetLinkingElement.
* @param aStream the character stream that holds the stylesheet data.
* @param aLineNumber the line number at which the stylesheet data started.
* @param aTitle the title of the sheet.
* @param aMedia the media string for the sheet.
* @param aObserver the observer to notify when the load completes.
* May be null.
* @param [out] aCompleted whether parsing of the sheet completed.
* @param [out] aIsAlternate whether the stylesheet ended up being an
* alternate sheet.
*/
NS_IMETHOD LoadInlineStyle(nsIContent* aElement,
nsIUnicharInputStream* aStream,
PRUint32 aLineNumber,
const nsSubstring& aTitle,
const nsSubstring& aMedia,
nsICSSLoaderObserver* aObserver,
PRBool* aCompleted,
PRBool* aIsAlternate) = 0;
/**
* Load a linked (document) stylesheet. If a successful result is returned,
* aObserver is guaranteed to be notified asynchronously once the sheet is
* loaded and marked complete. If an error is returned, aObserver will not
* be notified. In addition to loading the sheet, this method will insert it
* into the stylesheet list of this CSSLoader's document.
*
* @param aElement the element linking to the the stylesheet. May be null.
* @param aURL the URL of the sheet.
* @param aTitle the title of the sheet.
* @param aMedia the media string for the sheet.
* @param aHasAlternateRel whether the rel for this link included
* "alternate".
* @param aObserver the observer to notify when the load completes.
* May be null.
* @param [out] aIsAlternate whether the stylesheet actually ended up beinga
* an alternate sheet. Note that this need not match
* aHasAlternateRel.
*/
NS_IMETHOD LoadStyleLink(nsIContent* aElement,
nsIURI* aURL,
const nsSubstring& aTitle,
const nsSubstring& aMedia,
PRBool aHasAlternateRel,
nsICSSLoaderObserver* aObserver,
PRBool* aIsAlternate) = 0;
/**
* Load a child (@import-ed) style sheet. In addition to loading the sheet,
* this method will insert it into the child sheet list of aParentSheet. If
* there is no sheet currently being parsed and the child sheet is not
* complete when this method returns, then when the child sheet becomes
* complete aParentSheet will be QIed to nsICSSLoaderObserver and
* asynchronously notified, just like for LoadStyleLink. Note that if the
* child sheet is already complete when this method returns, no
* nsICSSLoaderObserver notification will be sent.
*
* @param aParentSheet the parent of this child sheet
* @param aURL the URL of the child sheet
* @param aMedia the already-parsed media list for the child sheet
* @param aRule the @import rule importing this child. This is used to
* properly order the child sheet list of aParentSheet.
*/
NS_IMETHOD LoadChildSheet(nsICSSStyleSheet* aParentSheet,
nsIURI* aURL,
nsMediaList* aMedia,
nsICSSImportRule* aRule) = 0;
/**
* Synchronously load and return the stylesheet at aURL. Any child sheets
* will also be loaded synchronously. Note that synchronous loads over some
* protocols may involve spinning up a new event loop, so use of this method
* does NOT guarantee not receiving any events before the sheet loads. This
* method can be used to load sheets not associated with a document.
*
* @param aURL the URL of the sheet to load
* @param [out] aSheet the loaded, complete sheet.
* @param aEnableUnsafeRules whether unsafe rules are enabled for this
* sheet load
* Unsafe rules are rules that can violate key Gecko invariants if misused.
* In particular, most anonymous box pseudoelements must be very carefully
* styled or we will have severe problems. Therefore unsafe rules should
* never be enabled for stylesheets controlled by untrusted sites; preferably
* unsafe rules should only be enabled for agent sheets.
*
* NOTE: At the moment, this method assumes the sheet will be UTF-8, but
* ideally it would allow arbitrary encodings. Callers should NOT depend on
* non-UTF8 sheets being treated as UTF-8 by this method.
*
* NOTE: A successful return from this method doesn't indicate anything about
* whether the data could be parsed as CSS and doesn't indicate anything
* about the status of child sheets of the returned sheet.
*/
NS_IMETHOD LoadSheetSync(nsIURI* aURL, PRBool aEnableUnsafeRules,
nsICSSStyleSheet** aSheet) = 0;
/**
* As above, but aEnableUnsafeRules is assumed false.
*/
nsresult LoadSheetSync(nsIURI* aURL, nsICSSStyleSheet** aSheet) {
return LoadSheetSync(aURL, PR_FALSE, aSheet);
}
/**
* Asynchronously load the stylesheet at aURL. If a successful result is
* returned, aObserver is guaranteed to be notified asynchronously once the
* sheet is loaded and marked complete. This method can be used to load
* sheets not associated with a document.
*
* @param aURL the URL of the sheet to load
* @param aOriginPrincipal the principal to use for security checks. This
* can be null to indicate that these checks should
* be skipped.
* @param aObserver the observer to notify when the load completes.
* Must not be null.
* @param [out] aSheet the sheet to load. Note that the sheet may well
* not be loaded by the time this method returns.
*/
NS_IMETHOD LoadSheet(nsIURI* aURL,
nsIPrincipal* aOriginPrincipal,
nsICSSLoaderObserver* aObserver,
nsICSSStyleSheet** aSheet) = 0;
/**
* Same as above, to be used when the caller doesn't care about the
* not-yet-loaded sheet.
*/
NS_IMETHOD LoadSheet(nsIURI* aURL,
nsIPrincipal* aOriginPrincipal,
nsICSSLoaderObserver* aObserver) = 0;
/**
* Stop loading all sheets. All nsICSSLoaderObservers involved will be
* notified with NS_BINDING_ABORTED as the status, possibly synchronously.
*/
NS_IMETHOD Stop(void) = 0;
/**
* Stop loading one sheet. The nsICSSLoaderObserver involved will be
* notified with NS_BINDING_ABORTED as the status, possibly synchronously.
*/
NS_IMETHOD StopLoadingSheet(nsIURI* aURL) = 0;
/**
* Whether the loader is enabled or not.
* When disabled, processing of new styles is disabled and an attempt
* to do so will fail with a return code of
* NS_ERROR_NOT_AVAILABLE. Note that this DOES NOT disable
* currently loading styles or already processed styles.
*/
NS_IMETHOD GetEnabled(PRBool *aEnabled) = 0;
NS_IMETHOD SetEnabled(PRBool aEnabled) = 0;
/**
* Return true if this nsICSSLoader has pending loads (ones that would send
* notifications to an nsICSSLoaderObserver attached to this nsICSSLoader).
* If called from inside nsICSSLoaderObserver::StyleSheetLoaded, this will
* return PR_FALSE if and only if that is the last StyleSheetLoaded
* notification the CSSLoader knows it's going to send. In other words, if
* two sheets load at once (via load coalescing, e.g.), HasPendingLoads()
* will return PR_TRUE during notification for the first one, and PR_FALSE
* during notification for the second one.
*/
NS_IMETHOD_(PRBool) HasPendingLoads() = 0;
/**
* Add an observer to this nsICSSLoader. The observer will be notified for
* all loads that would have notified their own observers (even if those
* loads don't have observers attached to them). Load-specific observers
* will be notified before generic observers. The CSSLoader holds a
* reference to the observer.
*
* aObserver must not be null.
*/
NS_IMETHOD AddObserver(nsICSSLoaderObserver* aObserver) = 0;
/**
* Remove an observer added via AddObserver.
*/
NS_IMETHOD_(void) RemoveObserver(nsICSSLoaderObserver* aObserver) = 0;
};
NS_DEFINE_STATIC_IID_ACCESSOR(nsICSSLoader, NS_ICSS_LOADER_IID)
nsresult
NS_NewCSSLoader(nsIDocument* aDocument, nsICSSLoader** aLoader);
nsresult
NS_NewCSSLoader(nsICSSLoader** aLoader);
#endif /* nsICSSLoader_h___ */