From 16f504a9dca3fe3b70568f67b7d41241ae485288 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 18:49:04 +0200 Subject: Adding upstream version 7.0.6-dfsg. Signed-off-by: Daniel Baumann --- src/libs/xpcom18a4/xpcom/io/nsFastLoadFile.h | 566 +++++++++++++++++++++++++++ 1 file changed, 566 insertions(+) create mode 100644 src/libs/xpcom18a4/xpcom/io/nsFastLoadFile.h (limited to 'src/libs/xpcom18a4/xpcom/io/nsFastLoadFile.h') diff --git a/src/libs/xpcom18a4/xpcom/io/nsFastLoadFile.h b/src/libs/xpcom18a4/xpcom/io/nsFastLoadFile.h new file mode 100644 index 00000000..9f6f061a --- /dev/null +++ b/src/libs/xpcom18a4/xpcom/io/nsFastLoadFile.h @@ -0,0 +1,566 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* ***** 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 FastLoad code. + * + * The Initial Developer of the Original Code is + * Netscape Communications Corporation. + * Portions created by the Initial Developer are Copyright (C) 2001 + * the Initial Developer. All Rights Reserved. + * + * Contributor(s): + * Brendan Eich (original author) + * + * 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 ***** */ + +#ifndef nsFastLoadFile_h___ +#define nsFastLoadFile_h___ + +/** + * Mozilla FastLoad file format and helper types. + */ + +#include "prtypes.h" +#include "pldhash.h" + +#include "nsBinaryStream.h" +#include "nsCOMPtr.h" +#include "nsDebug.h" +#include "nsID.h" +#include "nsMemory.h" +#include "nsVoidArray.h" + +#include "nsIFastLoadFileControl.h" +#include "nsIFastLoadService.h" +#include "nsISeekableStream.h" +#include "nsISupportsArray.h" + +/** + * FastLoad file Object ID (OID) is an identifier for multiply and cyclicly + * connected objects in the serialized graph of all reachable objects. + * + * Holy Mixed Metaphors: JS, after Common Lisp, uses #n= to define a "sharp + * variable" naming an object that's multiply or cyclicly connected, and #n# + * to stand for a connection to an already-defined object. We too call any + * object with multiple references "sharp", and (here it comes) any object + * with only one reference "dull". + * + * Note that only sharp objects require a mapping from OID to FastLoad file + * offset and other information. Dull objects can be serialized _in situ_ + * (where they are referenced) and deserialized when their (singular, shared) + * OID is scanned. + * + * We also compress 16-byte XPCOM IDs into 32-bit dense identifiers to save + * space. See nsFastLoadFooter, below, for the mapping data structure used to + * compute an nsID given an NSFastLoadID. + */ +typedef PRUint32 NSFastLoadID; // nsFastLoadFooter::mIDMap index +typedef PRUint32 NSFastLoadOID; // nsFastLoadFooter::mObjectMap index + +/** + * A Mozilla FastLoad file is an untagged (in general) stream of objects and + * primitive-type data. Small integers are fairly common, and could easily be + * confused for NSFastLoadIDs and NSFastLoadOIDs. To help catch bugs where + * reader and writer code fail to match, we XOR unlikely 32-bit numbers with + * NSFastLoad*IDs when storing and fetching. The following unlikely values are + * irrational numbers ((sqrt(5)-1)/2, sqrt(2)-1) represented in fixed point. + * + * The reader XORs, converts the ID to an index, and bounds-checks all array + * accesses that use the index. Array access code asserts that the index is in + * bounds, and returns a dummy array element if it isn't. + */ +#define MFL_ID_XOR_KEY 0x9E3779B9 // key XOR'd with ID when serialized +#define MFL_OID_XOR_KEY 0x6A09E667 // key XOR'd with OID when serialized + +/** + * An OID can be tagged to introduce the serialized definition of the object, + * or to stand for a strong or weak reference to that object. Thus the high + * 29 bits actually identify the object, and the low three bits tell whether + * the object is being defined or just referenced -- and via what inheritance + * chain or inner object, if necessary. + * + * The MFL_QUERY_INTERFACE_TAG bit helps us cope with aggregation and multiple + * inheritance: object identity follows the XPCOM rule, but a deserializer may + * need to query for an interface not on the primary inheritance chain ending + * in the nsISupports whose address uniquely identifies the XPCOM object being + * referenced or defined. + */ +#define MFL_OBJECT_TAG_BITS 3 +#define MFL_OBJECT_TAG_MASK PR_BITMASK(MFL_OBJECT_TAG_BITS) + +#define MFL_OBJECT_DEF_TAG 1U // object definition follows this OID +#define MFL_WEAK_REF_TAG 2U // OID weakly refers to a prior object + // NB: do not confuse with nsWeakPtr! +#define MFL_QUERY_INTERFACE_TAG 4U // QI object to the ID follows this OID + // NB: an NSFastLoadID, not an nsIID! + +/** + * The dull object identifier introduces the definition of all objects that + * have only one (necessarily strong) ref in the serialization. The definition + * appears at the point of reference. + */ +#define MFL_DULL_OBJECT_OID MFL_OBJECT_DEF_TAG + +/** + * Convert an OID to an index into nsFastLoadFooter::mObjectMap. + */ +#define MFL_OID_TO_SHARP_INDEX(oid) (((oid) >> MFL_OBJECT_TAG_BITS) - 1) +#define MFL_SHARP_INDEX_TO_OID(index) (((index) + 1) << MFL_OBJECT_TAG_BITS) + +/** + * Magic "number" at start of a FastLoad file. Inspired by the PNG "magic" + * string, which inspired XPCOM's typelib (.xpt) file magic. Guaranteed to be + * corrupted by FTP-as-ASCII and other likely errors, meaningful to clued-in + * humans, and ending in ^Z to terminate erroneous text input on Windows. + */ +#define MFL_FILE_MAGIC "XPCOM\nMozFASL\r\n\032" +#define MFL_FILE_MAGIC_SIZE 16 + +#define MFL_FILE_VERSION_0 0 +#define MFL_FILE_VERSION_1 1000 +#define MFL_FILE_VERSION 4 // fix to note singletons in object map + +/** + * Compute Fletcher's 16-bit checksum over aLength bytes starting at aBuffer, + * with the initial accumulators seeded from *aChecksum, and final checksum + * returned in *aChecksum. The return value is the number of unchecked bytes, + * which may be non-zero if aBuffer is misaligned or aLength is odd. Callers + * should copy any remaining bytes to the front of the next buffer. + * + * If aLastBuffer is false, do not check any bytes remaining due to misaligned + * aBuffer or odd aLength, instead returning the remaining byte count. But if + * aLastBuffer is true, treat aBuffer as the last buffer in the file and check + * every byte, returning 0. Here's a read-loop checksumming sketch: + * + * char buf[BUFSIZE]; + * PRUint32 len, rem = 0; + * PRUint32 checksum = 0; + * + * while (NS_SUCCEEDED(rv = Read(buf + rem, sizeof buf - rem, &len)) && len) { + * len += rem; + * rem = NS_AccumulateFastLoadChecksum(&checksum, + * NS_REINTERPRET_CAST(PRUint8*, buf), + * len, + * PR_FALSE); + * if (rem) + * memcpy(buf, buf + len - rem, rem); + * } + * + * if (rem) { + * NS_AccumulateFastLoadChecksum(&checksum, + * NS_REINTERPRET_CAST(PRUint8*, buf), + * rem, + * PR_TRUE); + * } + * + * After this, if NS_SUCCEEDED(rv), checksum contains a valid FastLoad sum. + */ +PR_EXTERN(PRUint32) +NS_AccumulateFastLoadChecksum(PRUint32 *aChecksum, + const PRUint8* aBuffer, + PRUint32 aLength, + PRBool aLastBuffer); + +PR_EXTERN(PRUint32) +NS_AddFastLoadChecksums(PRUint32 sum1, PRUint32 sum2, PRUint32 sum2ByteCount); + +/** + * Header at the start of a FastLoad file. + */ +struct nsFastLoadHeader { + char mMagic[MFL_FILE_MAGIC_SIZE]; + PRUint32 mChecksum; + PRUint32 mVersion; + PRUint32 mFooterOffset; + PRUint32 mFileSize; +}; + +/** + * Footer prefix structure (footer header, ugh), after which come arrays of + * structures or strings counted by these members. + */ +struct nsFastLoadFooterPrefix { + PRUint32 mNumIDs; + PRUint32 mNumSharpObjects; + PRUint32 mNumMuxedDocuments; + PRUint32 mNumDependencies; +}; + +struct nsFastLoadSharpObjectInfo { + PRUint32 mCIDOffset; // offset of object's NSFastLoadID and data + PRUint16 mStrongRefCnt; + PRUint16 mWeakRefCnt; // high bit is singleton flag, see below +}; + +#define MFL_SINGLETON_FLAG 0x8000 +#define MFL_WEAK_REFCNT_MASK 0x7fff + +#define MFL_GET_SINGLETON_FLAG(ip) ((ip)->mWeakRefCnt & MFL_SINGLETON_FLAG) +#define MFL_GET_WEAK_REFCNT(ip) ((ip)->mWeakRefCnt & MFL_WEAK_REFCNT_MASK) + +#define MFL_SET_SINGLETON_FLAG(ip) \ + ((ip)->mWeakRefCnt |= MFL_SINGLETON_FLAG) +#define MFL_SET_WEAK_REFCNT(ip,rc) \ + ((ip)->mWeakRefCnt = (((ip)->mWeakRefCnt & MFL_SINGLETON_FLAG) | (rc))) + +#define MFL_BUMP_WEAK_REFCNT(ip) (++(ip)->mWeakRefCnt) +#define MFL_DROP_WEAK_REFCNT(ip) (--(ip)->mWeakRefCnt) + +struct nsFastLoadMuxedDocumentInfo { + const char* mURISpec; + PRUint32 mInitialSegmentOffset; +}; + +// forward declarations of opaque types defined in nsFastLoadFile.cpp +struct nsDocumentMapReadEntry; +struct nsDocumentMapWriteEntry; + +// So nsFastLoadFileUpdater can verify that its nsIObjectInputStream parameter +// is an nsFastLoadFileReader. +#define NS_FASTLOADFILEREADER_IID \ + {0x7d37d1bb,0xcef3,0x4c5f,{0x97,0x68,0x0f,0x89,0x7f,0x1a,0xe1,0x40}} + +struct nsIFastLoadFileReader : public nsISupports { + NS_DEFINE_STATIC_IID_ACCESSOR(NS_FASTLOADFILEREADER_IID) +}; + +/** + * Inherit from the concrete class nsBinaryInputStream, which inherits from + * abstract nsIObjectInputStream but does not implement its direct methods. + * Though the names are not as clear as I'd like, this seems to be the best + * way to share nsBinaryStream.cpp code. + */ +class nsFastLoadFileReader + : public nsBinaryInputStream, + public nsIFastLoadReadControl, + public nsISeekableStream, + public nsIFastLoadFileReader +{ + public: + nsFastLoadFileReader(nsIInputStream *aStream) + : mCurrentDocumentMapEntry(nsnull) { + SetInputStream(aStream); + MOZ_COUNT_CTOR(nsFastLoadFileReader); + } + + virtual ~nsFastLoadFileReader() { + MOZ_COUNT_DTOR(nsFastLoadFileReader); + } + + private: + // nsISupports methods + NS_DECL_ISUPPORTS_INHERITED + + // overridden nsIObjectInputStream methods + NS_IMETHOD ReadObject(PRBool aIsStrongRef, nsISupports* *_retval); + NS_IMETHOD ReadID(nsID *aResult); + + // nsIFastLoadFileControl methods + NS_DECL_NSIFASTLOADFILECONTROL + + // nsIFastLoadReadControl methods + NS_DECL_NSIFASTLOADREADCONTROL + + // nsISeekableStream methods + NS_DECL_NSISEEKABLESTREAM + + // Override Read so we can demultiplex a document interleaved with others. + NS_IMETHOD Read(char* aBuffer, PRUint32 aCount, PRUint32 *aBytesRead); + + // Override ReadSegments too, as nsBinaryInputStream::ReadSegments does + // not call through our overridden Read method -- it calls directly into + // the underlying input stream. + NS_IMETHODIMP ReadSegments(nsWriteSegmentFun aWriter, void* aClosure, + PRUint32 aCount, PRUint32 *aResult); + + nsresult ReadHeader(nsFastLoadHeader *aHeader); + + /** + * In-memory representation of an indexed nsFastLoadSharpObjectInfo record. + */ + struct nsObjectMapEntry : public nsFastLoadSharpObjectInfo { + nsCOMPtr mReadObject; + PRInt64 mSkipOffset; + PRUint16 mSaveStrongRefCnt; // saved for an Update + PRUint16 mSaveWeakRefCnt; // after a Read + }; + + /** + * In-memory representation of the FastLoad file footer. + */ + struct nsFastLoadFooter : public nsFastLoadFooterPrefix { + nsFastLoadFooter() + : mIDMap(nsnull), + mObjectMap(nsnull) { + mDocumentMap.ops = mURIMap.ops = nsnull; + } + + ~nsFastLoadFooter() { + delete[] mIDMap; + delete[] mObjectMap; + if (mDocumentMap.ops) + PL_DHashTableFinish(&mDocumentMap); + if (mURIMap.ops) + PL_DHashTableFinish(&mURIMap); + } + + // These can't be static within GetID and GetSharpObjectEntry or the + // toolchains on HP-UX 10.20's, RH 7.0, and Mac OS X all barf at link + // time ("common symbols not allowed with MY_DHLIB output format", to + // quote the OS X rev of gcc). + static nsID gDummyID; + static nsObjectMapEntry gDummySharpObjectEntry; + + const nsID& GetID(NSFastLoadID aFastId) const { + PRUint32 index = aFastId - 1; + NS_ASSERTION(index < mNumIDs, "aFastId out of range"); + if (index >= mNumIDs) + return gDummyID; + return mIDMap[index]; + } + + nsObjectMapEntry& + GetSharpObjectEntry(NSFastLoadOID aOID) const { + PRUint32 index = MFL_OID_TO_SHARP_INDEX(aOID); + NS_ASSERTION(index < mNumSharpObjects, "aOID out of range"); + if (index >= mNumSharpObjects) + return gDummySharpObjectEntry; + return mObjectMap[index]; + } + + // Map from dense, zero-based, uint32 NSFastLoadID to 16-byte nsID. + nsID* mIDMap; + + // Map from dense, zero-based MFL_OID_TO_SHARP_INDEX(oid) to sharp + // object offset and refcnt information. + nsObjectMapEntry* mObjectMap; + + // Map from URI spec string to nsDocumentMapReadEntry, which helps us + // demultiplex a document's objects from among the interleaved object + // stream segments in the FastLoad file. + PLDHashTable mDocumentMap; + + // Fast mapping from URI object pointer to mDocumentMap entry, valid + // only while the muxed document is loading. + PLDHashTable mURIMap; + + // List of source filename dependencies that should trigger regeneration + // of the FastLoad file. + nsCOMPtr mDependencies; + }; + + nsresult ReadFooter(nsFastLoadFooter *aFooter); + nsresult ReadFooterPrefix(nsFastLoadFooterPrefix *aFooterPrefix); + nsresult ReadSlowID(nsID *aID); + nsresult ReadFastID(NSFastLoadID *aID); + nsresult ReadSharpObjectInfo(nsFastLoadSharpObjectInfo *aInfo); + nsresult ReadMuxedDocumentInfo(nsFastLoadMuxedDocumentInfo *aInfo); + nsresult DeserializeObject(nsISupports* *aObject); + + nsresult Open(); + NS_IMETHOD Close(); + + protected: + nsFastLoadHeader mHeader; + nsFastLoadFooter mFooter; + + nsDocumentMapReadEntry* mCurrentDocumentMapEntry; + + friend class nsFastLoadFileUpdater; +}; + +NS_COM nsresult +NS_NewFastLoadFileReader(nsIObjectInputStream* *aResult, + nsIInputStream* aSrcStream); + +/** + * Inherit from the concrete class nsBinaryInputStream, which inherits from + * abstract nsIObjectInputStream but does not implement its direct methods. + * Though the names are not as clear as I'd like, this seems to be the best + * way to share nsBinaryStream.cpp code. + */ +class nsFastLoadFileWriter + : public nsBinaryOutputStream, + public nsIFastLoadWriteControl, + public nsISeekableStream +{ + public: + nsFastLoadFileWriter(nsIOutputStream *aStream, nsIFastLoadFileIO* aFileIO) + : mCurrentDocumentMapEntry(nsnull), + mFileIO(aFileIO) + { + SetOutputStream(aStream); + mHeader.mChecksum = 0; + mIDMap.ops = mObjectMap.ops = mDocumentMap.ops = mURIMap.ops = nsnull; + mDependencyMap.ops = nsnull; + MOZ_COUNT_CTOR(nsFastLoadFileWriter); + } + + virtual ~nsFastLoadFileWriter() + { + if (mIDMap.ops) + PL_DHashTableFinish(&mIDMap); + if (mObjectMap.ops) + PL_DHashTableFinish(&mObjectMap); + if (mDocumentMap.ops) + PL_DHashTableFinish(&mDocumentMap); + if (mURIMap.ops) + PL_DHashTableFinish(&mURIMap); + if (mDependencyMap.ops) + PL_DHashTableFinish(&mDependencyMap); + MOZ_COUNT_DTOR(nsFastLoadFileWriter); + } + + private: + // nsISupports methods + NS_DECL_ISUPPORTS_INHERITED + + // overridden nsIObjectOutputStream methods + NS_IMETHOD WriteObject(nsISupports* aObject, PRBool aIsStrongRef); + NS_IMETHOD WriteSingleRefObject(nsISupports* aObject); + NS_IMETHOD WriteCompoundObject(nsISupports* aObject, + const nsIID& aIID, + PRBool aIsStrongRef); + NS_IMETHOD WriteID(const nsID& aID); + + // nsIFastLoadFileControl methods + NS_DECL_NSIFASTLOADFILECONTROL + + // nsIFastLoadWriteControl methods + NS_DECL_NSIFASTLOADWRITECONTROL + + // nsISeekableStream methods + NS_DECL_NSISEEKABLESTREAM + + nsresult MapID(const nsID& aSlowID, NSFastLoadID *aResult); + + nsresult WriteHeader(nsFastLoadHeader *aHeader); + nsresult WriteFooter(); + nsresult WriteFooterPrefix(const nsFastLoadFooterPrefix& aFooterPrefix); + nsresult WriteSlowID(const nsID& aID); + nsresult WriteFastID(NSFastLoadID aID); + nsresult WriteSharpObjectInfo(const nsFastLoadSharpObjectInfo& aInfo); + nsresult WriteMuxedDocumentInfo(const nsFastLoadMuxedDocumentInfo& aInfo); + + nsresult Init(); + nsresult Open(); + NS_IMETHOD Close(); + + nsresult WriteObjectCommon(nsISupports* aObject, + PRBool aIsStrongRef, + PRUint32 aQITag); + + static PLDHashOperator PR_CALLBACK + IDMapEnumerate(PLDHashTable *aTable, + PLDHashEntryHdr *aHdr, + PRUint32 aNumber, + void *aData); + + static PLDHashOperator PR_CALLBACK + ObjectMapEnumerate(PLDHashTable *aTable, + PLDHashEntryHdr *aHdr, + PRUint32 aNumber, + void *aData); + + static PLDHashOperator PR_CALLBACK + DocumentMapEnumerate(PLDHashTable *aTable, + PLDHashEntryHdr *aHdr, + PRUint32 aNumber, + void *aData); + + static PLDHashOperator PR_CALLBACK + DependencyMapEnumerate(PLDHashTable *aTable, + PLDHashEntryHdr *aHdr, + PRUint32 aNumber, + void *aData); + + protected: + nsFastLoadHeader mHeader; + + PLDHashTable mIDMap; + PLDHashTable mObjectMap; + PLDHashTable mDocumentMap; + PLDHashTable mURIMap; + PLDHashTable mDependencyMap; + + nsDocumentMapWriteEntry* mCurrentDocumentMapEntry; + nsCOMPtr mFileIO; +}; + +NS_COM nsresult +NS_NewFastLoadFileWriter(nsIObjectOutputStream* *aResult, + nsIOutputStream* aDestStream, + nsIFastLoadFileIO* aFileIO); + +/** + * Subclass of nsFastLoadFileWriter, friend of nsFastLoadFileReader which it + * wraps when a FastLoad file needs to be updated. The wrapped reader can be + * used to demulitplex data for documents already in the FastLoad file, while + * the updater writes new data over the old footer, then writes a new footer + * that maps all data on Close. + */ +class nsFastLoadFileUpdater + : public nsFastLoadFileWriter, + nsIFastLoadFileIO +{ + public: + nsFastLoadFileUpdater(nsIOutputStream* aOutputStream) + : nsFastLoadFileWriter(aOutputStream, nsnull) { + MOZ_COUNT_CTOR(nsFastLoadFileUpdater); + } + + virtual ~nsFastLoadFileUpdater() { + MOZ_COUNT_DTOR(nsFastLoadFileUpdater); + } + + private: + // nsISupports methods + NS_DECL_ISUPPORTS_INHERITED + + // nsIFastLoadFileIO methods + NS_DECL_NSIFASTLOADFILEIO + + nsresult Open(nsFastLoadFileReader* aReader); + NS_IMETHOD Close(); + + static PLDHashOperator PR_CALLBACK + CopyReadDocumentMapEntryToUpdater(PLDHashTable *aTable, + PLDHashEntryHdr *aHdr, + PRUint32 aNumber, + void *aData); + + friend class nsFastLoadFileReader; + + protected: + nsCOMPtr mInputStream; +}; + +NS_COM nsresult +NS_NewFastLoadFileUpdater(nsIObjectOutputStream* *aResult, + nsIOutputStream* aOutputStream, + nsIObjectInputStream* aReaderAsStream); + +#endif // nsFastLoadFile_h___ -- cgit v1.2.3