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 "nsISupports.idl"
michael@0: 
michael@0: interface nsIRequest;
michael@0: 
michael@0: /**
michael@0:  * Content sniffer interface. Components implementing this interface can
michael@0:  * determine a MIME type from a chunk of bytes.
michael@0:  */
michael@0: [scriptable, uuid(a5772d1b-fc63-495e-a169-96e8d3311af0)]
michael@0: interface nsIContentSniffer : nsISupports
michael@0: {
michael@0:   /**
michael@0:    * Given a chunk of data, determines a MIME type. Information from the given
michael@0:    * request may be used in order to make a better decision.
michael@0:    *
michael@0:    * @param aRequest The request where this data came from. May be null.
michael@0:    * @param aData Data to check
michael@0:    * @param aLength Length of the data
michael@0:    *
michael@0:    * @return The content type
michael@0:    *
michael@0:    * @throw NS_ERROR_NOT_AVAILABLE if no MIME type could be determined.
michael@0:    *
michael@0:    * @note Implementations should consider the request read-only. Especially,
michael@0:    * they should not attempt to set the content type property that subclasses of
michael@0:    * nsIRequest might offer.
michael@0:    */
michael@0:   ACString getMIMETypeFromContent(in nsIRequest aRequest,
michael@0:                                   [const,array,size_is(aLength)] in octet aData,
michael@0:                                   in unsigned long aLength);
michael@0: };