nsMultiMixedConv.h

mozilla-central/netwerk/streamconv/converters/nsMultiMixedConv.h (file symbol)

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/* -*- Mode: C++; tab-width: 4; 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/. */

#ifndef __nsmultimixedconv__h__

#define __nsmultimixedconv__h__

#include "nsIStreamConverter.h"

#include "nsIChannel.h"

#include "nsString.h"

#include "nsCOMPtr.h"

#include "nsIByteRangeRequest.h"

#include "nsIMultiPartChannel.h"

#include "mozilla/Attributes.h"

#include "mozilla/IncrementalTokenizer.h"

#include "nsHttpResponseHead.h"

#include "mozilla/UniquePtr.h"

#define NS_MULTIMIXEDCONVERTER_CID                 \

  { /* 7584CE90-5B25-11d3-A175-0050041CAF44 */     \

    0x7584ce90, 0x5b25, 0x11d3, {                  \

      0xa1, 0x75, 0x0, 0x50, 0x4, 0x1c, 0xaf, 0x44 \

    }                                              \

//

// nsPartChannel is a "dummy" channel which represents an individual part of

// a multipart/mixed stream...

//

// Instances on this channel are passed out to the consumer through the

// nsIStreamListener interface.

//

class nsPartChannel final : public nsIChannel,

                            public nsIByteRangeRequest,

                            public nsIMultiPartChannel {

 public:

  nsPartChannel(nsIChannel* aMultipartChannel, uint32_t aPartID,

                bool aIsFirstPart, nsIStreamListener* aListener);

  void InitializeByteRange(int64_t aStart, int64_t aEnd);

  void SetIsLastPart() { mIsLastPart = true; }

  nsresult SendOnStartRequest(nsISupports* aContext);

  nsresult SendOnDataAvailable(nsISupports* aContext, nsIInputStream* aStream,

                               uint64_t aOffset, uint32_t aLen);

  nsresult SendOnStopRequest(nsISupports* aContext, nsresult aStatus);

  /* SetContentDisposition expects the full value of the Content-Disposition

   * header */

  void SetContentDisposition(const nsACString& aContentDispositionHeader);

  // TODO(ER): This appears to be dead code

  void SetResponseHead(mozilla::net::nsHttpResponseHead* head) {

    mResponseHead.reset(head);

  NS_DECL_ISUPPORTS

  NS_DECL_NSIREQUEST

  NS_DECL_NSICHANNEL

  NS_DECL_NSIBYTERANGEREQUEST

  NS_DECL_NSIMULTIPARTCHANNEL

 protected:

  ~nsPartChannel() = default;

 protected:

  nsCOMPtr<nsIChannel> mMultipartChannel;

  nsCOMPtr<nsIStreamListener> mListener;

  mozilla::UniquePtr<mozilla::net::nsHttpResponseHead> mResponseHead;

  nsresult mStatus{NS_OK};

  nsLoadFlags mLoadFlags{0};

  nsCOMPtr<nsILoadGroup> mLoadGroup;

  nsCString mContentType;

  nsCString mContentCharset;

  uint32_t mContentDisposition{0};

  nsString mContentDispositionFilename;

  nsCString mContentDispositionHeader;

  uint64_t mContentLength{UINT64_MAX};

  bool mIsByteRangeRequest{false};

  int64_t mByteRangeStart{0};

  int64_t mByteRangeEnd{0};

  uint32_t mPartID;  // unique ID that can be used to identify

                     // this part of the multipart document

  bool mIsFirstPart;

  bool mIsLastPart{false};

};

// The nsMultiMixedConv stream converter converts a stream of type

// "multipart/x-mixed-replace" to it's subparts. There was some debate as to

// whether or not the functionality desired when HTTP confronted this type

// required a stream converter. After all, this type really prompts various

// viewer related actions rather than stream conversion. There simply needs to

// be a piece in place that can strip out the multiple parts of a stream of this

// type, and "display" them accordingly.

//

// With that said, this "stream converter" spends more time packaging up the sub

// parts of the main stream and sending them off the destination stream

// listener, than doing any real stream parsing/converting.

//

// WARNING: This converter requires that it's destination stream listener be

//   able to handle multiple OnStartRequest(), OnDataAvailable(), and

//   OnStopRequest() call combinations.  Each series represents the beginning,

//   data production, and ending phase of each sub- part of the original

//   stream.

//

// NOTE: this MIME-type is used by HTTP, *not* SMTP, or IMAP.

//

// NOTE: For reference, a general description of how this MIME type should be

//   handled via HTTP, see

//   http://home.netscape.com/assist/net_sites/pushpull.html . Note that real

//   world server content deviates considerably from this overview.

//

// Implementation assumptions:

//  Assumed structue:

//  --BoundaryToken[\r]\n

//  content-type: foo/bar[\r]\n

//  ... (other headers if any)

//  [\r]\n (second line feed to delimit end of headers)

//  data

//  --BoundaryToken-- (end delimited by final "--")

//

// linebreaks can be either CRLF or LFLF. linebreaks preceding

// boundary tokens are NOT considered part of the data. BoundaryToken

// is any opaque string.

//

//

class nsMultiMixedConv : public nsIStreamConverter {

 public:

  NS_DECL_ISUPPORTS

  NS_DECL_NSISTREAMCONVERTER

  NS_DECL_NSISTREAMLISTENER

  NS_DECL_NSITHREADRETARGETABLESTREAMLISTENER

  NS_DECL_NSIREQUESTOBSERVER

  explicit nsMultiMixedConv();

 protected:

  using Token = mozilla::IncrementalTokenizer::Token;

  virtual ~nsMultiMixedConv() = default;

  nsresult SendStart();

  void AccumulateData(Token const& aToken);

  nsresult SendData();

  nsresult SendStop(nsresult aStatus);

  // member data

  nsCOMPtr<nsIStreamListener> mFinalListener;  // this guy gets the converted

                                               // data via his OnDataAvailable()

  nsCOMPtr<nsIChannel>

      mChannel;  // The channel as we get in in OnStartRequest call

  RefPtr<nsPartChannel> mPartChannel;  // the channel for the given part we're

                                       // processing. one channel per part.

  nsCOMPtr<nsISupports> mContext;

  nsCString mContentType;

  nsCString mContentDisposition;

  nsCString mContentSecurityPolicy;

  nsCString mRootContentSecurityPolicy;

  uint64_t mContentLength{UINT64_MAX};

  uint64_t mTotalSent{0};

  // The following members are for tracking the byte ranges in

  // multipart/mixed content which specified the 'Content-Range:'

  // header...

  int64_t mByteRangeStart{0};

  int64_t mByteRangeEnd{0};

  bool mIsByteRangeRequest{false};

  // This flag is set first time we create a part channel.

  // We use it to prevent duplicated OnStopRequest call on the listener

  // when we fail from some reason to ever create a part channel that

  // ensures correct notifications.

  bool mRequestListenerNotified{false};

  uint32_t mCurrentPartID{0};

  // Flag preventing reenter of OnDataAvailable in case the target listener

  // ends up spinning the event loop.

  bool mInOnDataAvailable{false};

  // Current state of the incremental parser

  enum EParserState {

    PREAMBLE,

    BOUNDARY_CRLF,

    HEADER_NAME,

    HEADER_SEP,

    HEADER_VALUE,

    BODY_INIT,

    BODY,

    TRAIL_DASH1,

    TRAIL_DASH2,

    EPILOGUE,

    INIT = PREAMBLE

  } mParserState{INIT};

  // Response part header value, valid when we find a header name

  // we recognize.

  enum EHeader : uint32_t {

    HEADER_FIRST,

    HEADER_CONTENT_TYPE = HEADER_FIRST,

    HEADER_CONTENT_LENGTH,

    HEADER_CONTENT_DISPOSITION,

    HEADER_SET_COOKIE,

    HEADER_CONTENT_RANGE,

    HEADER_RANGE,

    HEADER_CONTENT_SECURITY_POLICY,

    HEADER_UNKNOWN

  } mResponseHeader{HEADER_UNKNOWN};

  // Cumulated value of a response header.

  nsCString mResponseHeaderValue;

  nsCString mBoundary;

  mozilla::IncrementalTokenizer mTokenizer;

  // When in the "body parsing" mode, see below, we cumulate raw data

  // incrementally to mainly avoid any unnecessary granularity.

  // mRawData points to the first byte in the tokenizer buffer where part

  // body data begins or continues.  mRawDataLength is a cumulated length

  // of that data during a single tokenizer input feed.  This is always

  // flushed right after we fed the tokenizer.

  nsACString::const_char_iterator mRawData{nullptr};

  nsACString::size_type mRawDataLength{0};

  // At the start we don't know if the server will be sending boundary with

  // or without the leading dashes.

  Token mBoundaryToken;

  Token mBoundaryTokenWithDashes;

  // We need these custom tokens to allow finding CRLF when in the binary mode.

  // CRLF before boundary is considered part of the boundary and not part of

  // the data.

  Token mLFToken;

  Token mCRLFToken;

  // Custom tokens for each of the response headers we recognize.

  Token mHeaderTokens[HEADER_UNKNOWN];

  // Resets values driven by part headers, like content type, to their defaults,

  // called at the start of every part processing.

  void HeadersToDefault();

  // Processes captured value of mResponseHeader header.

  nsresult ProcessHeader();

  // Switches the parser and tokenizer state to "binary mode" which only

  // searches for the 'CRLF boundary' delimiter.

  void SwitchToBodyParsing();

  // Switches to the default mode, we are in this mode when parsing headers and

  // control data around the boundary delimiters.

  void SwitchToControlParsing();

  // Turns on or off recognition of the headers we recognize in part heads.

  void SetHeaderTokensEnabled(bool aEnable);

  // The main parser callback called by the IncrementalTokenizer

  // instance from OnDataAvailable or OnStopRequest.

  nsresult ConsumeToken(Token const& token);

};

#endif /* __nsmultimixedconv__h__ */