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/* -*- 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
#ifndef nsUnknownDecoder_h__
#define nsUnknownDecoder_h__
#include "nsIStreamConverter.h"
#include "nsIThreadRetargetableStreamListener.h"
#include "nsIContentSniffer.h"
#include "mozilla/Mutex.h"
#include "mozilla/Atomics.h"
#include "nsCOMPtr.h"
#include "nsString.h"
#define NS_UNKNOWNDECODER_CID \
{ /* 7d7008a0-c49a-11d3-9b22-0080c7cb1080 */ \
0x7d7008a0, 0xc49a, 0x11d3, { \
0x9b, 0x22, 0x00, 0x80, 0xc7, 0xcb, 0x10, 0x80 \
} \
}
class nsUnknownDecoder : public nsIStreamConverter, public nsIContentSniffer {
public:
// nsISupports methods
NS_DECL_ISUPPORTS
// nsIStreamConverter methods
NS_DECL_NSISTREAMCONVERTER
// nsIStreamListener methods
NS_DECL_NSISTREAMLISTENER
// nsIRequestObserver methods
NS_DECL_NSIREQUESTOBSERVER
// nsIContentSniffer methods
NS_DECL_NSICONTENTSNIFFER
// nsIThreadRetargetableStreamListener methods
NS_DECL_NSITHREADRETARGETABLESTREAMLISTENER
explicit nsUnknownDecoder(nsIStreamListener* aListener = nullptr);
protected:
virtual ~nsUnknownDecoder();
virtual void DetermineContentType(nsIRequest* aRequest);
nsresult FireListenerNotifications(nsIRequest* request, nsISupports* aCtxt);
class ConvertedStreamListener : public nsIStreamListener {
public:
explicit ConvertedStreamListener(nsUnknownDecoder* aDecoder);
NS_DECL_ISUPPORTS
NS_DECL_NSIREQUESTOBSERVER
NS_DECL_NSISTREAMLISTENER
private:
virtual ~ConvertedStreamListener() = default;
static nsresult AppendDataToString(nsIInputStream* inputStream,
void* closure, const char* rawSegment,
uint32_t toOffset, uint32_t count,
uint32_t* writeCount);
nsUnknownDecoder* mDecoder;
};
protected:
nsCOMPtr<nsIStreamListener> mNextListener;
// Various sniffer functions. Returning true means that a type
// was determined; false means no luck.
bool SniffForHTML(nsIRequest* aRequest);
bool SniffForXML(nsIRequest* aRequest);
// SniffURI guesses at the content type based on the URI (typically
// using the extentsion)
bool SniffURI(nsIRequest* aRequest);
// LastDitchSniff guesses at text/plain vs. application/octet-stream
// by just looking at whether the data contains null bytes, and
// maybe at the fraction of chars with high bit set. Use this only
// as a last-ditch attempt to decide a content type!
bool LastDitchSniff(nsIRequest* aRequest);
/**
* An entry struct for our array of sniffers. Each entry has either
* a type associated with it (set these with the SNIFFER_ENTRY macro)
* or a function to be executed (set these with the
* SNIFFER_ENTRY_WITH_FUNC macro). The function should take a single
* nsIRequest* and returns bool -- true if it sets mContentType,
* false otherwise
*/
struct nsSnifferEntry {
using TypeSniffFunc = bool (nsUnknownDecoder::*)(nsIRequest*);
const char* mBytes;
uint32_t mByteLen;
// Exactly one of mMimeType and mContentTypeSniffer should be set non-null
const char* mMimeType;
TypeSniffFunc mContentTypeSniffer;
};
#define SNIFFER_ENTRY(_bytes, _type) \
{ _bytes, sizeof(_bytes) - 1, _type, nullptr }
#define SNIFFER_ENTRY_WITH_FUNC(_bytes, _func) \
{ _bytes, sizeof(_bytes) - 1, nullptr, _func }
static nsSnifferEntry sSnifferEntries[];
static uint32_t sSnifferEntryNum;
// We guarantee in order delivery of OnStart, OnStop and OnData, therefore
// we do not need proper locking for mBuffer.
mozilla::Atomic<char*> mBuffer;
mozilla::Atomic<uint32_t> mBufferLen;
nsCString mContentType;
// This mutex syncs: mContentType, mDecodedData and mNextListener.
mutable mozilla::Mutex mMutex MOZ_UNANNOTATED;
protected:
nsresult ConvertEncodedData(nsIRequest* request, const char* data,
uint32_t length);
nsCString mDecodedData; // If data are encoded this will be uncompress data.
};
#define NS_BINARYDETECTOR_CID \
{ /* a2027ec6-ba0d-4c72-805d-148233f5f33c */ \
0xa2027ec6, 0xba0d, 0x4c72, { \
0x80, 0x5d, 0x14, 0x82, 0x33, 0xf5, 0xf3, 0x3c \
} \
}
/**
* Class that detects whether a data stream is text or binary. This reuses
* most of nsUnknownDecoder except the actual content-type determination logic
* -- our overridden DetermineContentType simply calls LastDitchSniff and sets
* the type to APPLICATION_GUESS_FROM_EXT if the data is detected as binary.
*/
class nsBinaryDetector : public nsUnknownDecoder {
protected:
virtual void DetermineContentType(nsIRequest* aRequest) override;
};
#endif /* nsUnknownDecoder_h__ */