michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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: #ifndef nsUnknownDecoder_h__
michael@0: #define nsUnknownDecoder_h__
michael@0: 
michael@0: #include "nsIStreamConverter.h"
michael@0: #include "nsIContentSniffer.h"
michael@0: 
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsString.h"
michael@0: 
michael@0: #define NS_UNKNOWNDECODER_CID                        \
michael@0: { /* 7d7008a0-c49a-11d3-9b22-0080c7cb1080 */         \
michael@0:     0x7d7008a0,                                      \
michael@0:     0xc49a,                                          \
michael@0:     0x11d3,                                          \
michael@0:     {0x9b, 0x22, 0x00, 0x80, 0xc7, 0xcb, 0x10, 0x80}       \
michael@0: }
michael@0: 
michael@0: 
michael@0: class nsUnknownDecoder : public nsIStreamConverter, public nsIContentSniffer
michael@0: {
michael@0: public:
michael@0:   // nsISupports methods
michael@0:   NS_DECL_ISUPPORTS
michael@0: 
michael@0:   // nsIStreamConverter methods
michael@0:   NS_DECL_NSISTREAMCONVERTER
michael@0: 
michael@0:   // nsIStreamListener methods
michael@0:   NS_DECL_NSISTREAMLISTENER
michael@0: 
michael@0:   // nsIRequestObserver methods
michael@0:   NS_DECL_NSIREQUESTOBSERVER
michael@0: 
michael@0:   // nsIContentSniffer methods
michael@0:   NS_DECL_NSICONTENTSNIFFER
michael@0: 
michael@0:   nsUnknownDecoder();
michael@0: 
michael@0: protected:
michael@0:   virtual ~nsUnknownDecoder();
michael@0: 
michael@0:   virtual void DetermineContentType(nsIRequest* aRequest);
michael@0:   nsresult FireListenerNotifications(nsIRequest* request, nsISupports *aCtxt);
michael@0: 
michael@0: protected:
michael@0:   nsCOMPtr<nsIStreamListener> mNextListener;
michael@0: 
michael@0:   // Function to use to check whether sniffing some potentially
michael@0:   // dangerous types (eg HTML) is ok for this request.  We can disable
michael@0:   // sniffing for local files if needed using this.  Just a security
michael@0:   // precation thingy... who knows when we suddenly need to flip this
michael@0:   // pref?
michael@0:   bool AllowSniffing(nsIRequest* aRequest);
michael@0:   
michael@0:   // Various sniffer functions.  Returning true means that a type
michael@0:   // was determined; false means no luck.
michael@0:   bool SniffForHTML(nsIRequest* aRequest);
michael@0:   bool SniffForXML(nsIRequest* aRequest);
michael@0: 
michael@0:   // SniffURI guesses at the content type based on the URI (typically
michael@0:   // using the extentsion)
michael@0:   bool SniffURI(nsIRequest* aRequest);
michael@0: 
michael@0:   // LastDitchSniff guesses at text/plain vs. application/octet-stream
michael@0:   // by just looking at whether the data contains null bytes, and
michael@0:   // maybe at the fraction of chars with high bit set.  Use this only
michael@0:   // as a last-ditch attempt to decide a content type!
michael@0:   bool LastDitchSniff(nsIRequest* aRequest);
michael@0: 
michael@0:   /**
michael@0:    * An entry struct for our array of sniffers.  Each entry has either
michael@0:    * a type associated with it (set these with the SNIFFER_ENTRY macro)
michael@0:    * or a function to be executed (set these with the
michael@0:    * SNIFFER_ENTRY_WITH_FUNC macro).  The function should take a single
michael@0:    * nsIRequest* and returns bool -- true if it sets mContentType,
michael@0:    * false otherwise
michael@0:    */
michael@0:   struct nsSnifferEntry {
michael@0:     typedef bool (nsUnknownDecoder::*TypeSniffFunc)(nsIRequest* aRequest);
michael@0:     
michael@0:     const char* mBytes;
michael@0:     uint32_t mByteLen;
michael@0:     
michael@0:     // Exactly one of mMimeType and mContentTypeSniffer should be set non-null
michael@0:     const char* mMimeType;
michael@0:     TypeSniffFunc mContentTypeSniffer;
michael@0:   };
michael@0: 
michael@0: #define SNIFFER_ENTRY(_bytes, _type) \
michael@0:   { _bytes, sizeof(_bytes) - 1, _type, nullptr }
michael@0: 
michael@0: #define SNIFFER_ENTRY_WITH_FUNC(_bytes, _func) \
michael@0:   { _bytes, sizeof(_bytes) - 1, nullptr, _func }
michael@0: 
michael@0:   static nsSnifferEntry sSnifferEntries[];
michael@0:   static uint32_t sSnifferEntryNum;
michael@0:   
michael@0:   char *mBuffer;
michael@0:   uint32_t mBufferLen;
michael@0:   bool mRequireHTMLsuffix;
michael@0: 
michael@0:   nsCString mContentType;
michael@0: 
michael@0: };
michael@0: 
michael@0: #define NS_BINARYDETECTOR_CID                        \
michael@0: { /* a2027ec6-ba0d-4c72-805d-148233f5f33c */         \
michael@0:     0xa2027ec6,                                      \
michael@0:     0xba0d,                                          \
michael@0:     0x4c72,                                          \
michael@0:     {0x80, 0x5d, 0x14, 0x82, 0x33, 0xf5, 0xf3, 0x3c} \
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Class that detects whether a data stream is text or binary.  This reuses
michael@0:  * most of nsUnknownDecoder except the actual content-type determination logic
michael@0:  * -- our overridden DetermineContentType simply calls LastDitchSniff and sets
michael@0:  * the type to APPLICATION_GUESS_FROM_EXT if the data is detected as binary.
michael@0:  */
michael@0: class nsBinaryDetector : public nsUnknownDecoder
michael@0: {
michael@0: protected:
michael@0:   virtual void DetermineContentType(nsIRequest* aRequest);
michael@0: };
michael@0: 
michael@0: #define NS_BINARYDETECTOR_CATEGORYENTRY \
michael@0:   { NS_CONTENT_SNIFFER_CATEGORY, "Binary Detector", NS_BINARYDETECTOR_CONTRACTID }
michael@0: 
michael@0: #endif /* nsUnknownDecoder_h__ */
michael@0: