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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /parser/htmlparser/nsScanner.cpp | |
parent | Initial commit. (diff) | |
download | firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'parser/htmlparser/nsScanner.cpp')
-rw-r--r-- | parser/htmlparser/nsScanner.cpp | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/parser/htmlparser/nsScanner.cpp b/parser/htmlparser/nsScanner.cpp new file mode 100644 index 0000000000..36a14e1083 --- /dev/null +++ b/parser/htmlparser/nsScanner.cpp @@ -0,0 +1,331 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=2 sw=2 et tw=78: */ +/* 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/. */ + +// #define __INCREMENTAL 1 + +#include "nsScanner.h" + +#include "mozilla/Attributes.h" +#include "mozilla/DebugOnly.h" +#include "mozilla/Encoding.h" +#include "mozilla/UniquePtr.h" +#include "nsDebug.h" +#include "nsReadableUtils.h" +#include "nsUTF8Utils.h" // for LossyConvertEncoding +#include "nsCRT.h" +#include "nsParser.h" +#include "nsCharsetSource.h" + +nsReadEndCondition::nsReadEndCondition(const char16_t* aTerminateChars) + : mChars(aTerminateChars), + mFilter(char16_t(~0)) // All bits set +{ + // Build filter that will be used to filter out characters with + // bits that none of the terminal chars have. This works very well + // because terminal chars often have only the last 4-6 bits set and + // normal ascii letters have bit 7 set. Other letters have even higher + // bits set. + + // Calculate filter + const char16_t* current = aTerminateChars; + char16_t terminalChar = *current; + while (terminalChar) { + mFilter &= ~terminalChar; + ++current; + terminalChar = *current; + } +} + +/** + * Use this constructor if you want i/o to be based on + * a single string you hand in during construction. + * This short cut was added for Javascript. + * + * @update gess 5/12/98 + * @param aMode represents the parser mode (nav, other) + * @return + */ +nsScanner::nsScanner(const nsAString& anHTMLString, bool aIncremental) + : mIncremental(aIncremental) { + MOZ_COUNT_CTOR(nsScanner); + + AppendToBuffer(anHTMLString); + MOZ_ASSERT(mMarkPosition == mCurrentPosition); +} + +/** + * Use this constructor if you want i/o to be based on strings + * the scanner receives. If you pass a null filename, you + * can still provide data to the scanner via append. + */ +nsScanner::nsScanner(nsIURI* aURI) : mURI(aURI), mIncremental(true) { + MOZ_COUNT_CTOR(nsScanner); + + // XXX This is a big hack. We need to initialize the iterators to something. + // What matters is that mCurrentPosition == mEndPosition, so that our methods + // believe that we are at EOF (see bug 182067). We null out mCurrentPosition + // so that we have some hope of catching null pointer dereferences associated + // with this hack. --darin + memset(&mCurrentPosition, 0, sizeof(mCurrentPosition)); + mMarkPosition = mCurrentPosition; + mEndPosition = mCurrentPosition; + + // XML defaults to UTF-8 and about:blank is UTF-8, too. + SetDocumentCharset(UTF_8_ENCODING, kCharsetFromDocTypeDefault); +} + +nsresult nsScanner::SetDocumentCharset(NotNull<const Encoding*> aEncoding, + int32_t aSource) { + if (aSource < mCharsetSource) // priority is lower than the current one + return NS_OK; + + mCharsetSource = aSource; + nsCString charsetName; + aEncoding->Name(charsetName); + if (!mCharset.IsEmpty() && charsetName.Equals(mCharset)) { + return NS_OK; // no difference, don't change it + } + + // different, need to change it + + mCharset.Assign(charsetName); + + mUnicodeDecoder = aEncoding->NewDecoderWithBOMRemoval(); + + return NS_OK; +} + +/** + * default destructor + * + * @update gess 3/25/98 + * @param + * @return + */ +nsScanner::~nsScanner() { MOZ_COUNT_DTOR(nsScanner); } + +/** + * Resets current offset position of input stream to marked position. + * This allows us to back up to this point if the need should arise, + * such as when tokenization gets interrupted. + * NOTE: IT IS REALLY BAD FORM TO CALL RELEASE WITHOUT CALLING MARK FIRST! + * + * @update gess 5/12/98 + * @param + * @return + */ +void nsScanner::RewindToMark(void) { + if (mSlidingBuffer) { + mCurrentPosition = mMarkPosition; + } +} + +/** + * Records current offset position in input stream. This allows us + * to back up to this point if the need should arise, such as when + * tokenization gets interrupted. + * + * @update gess 7/29/98 + * @param + * @return + */ +int32_t nsScanner::Mark() { + int32_t distance = 0; + if (mSlidingBuffer) { + nsScannerIterator oldStart; + mSlidingBuffer->BeginReading(oldStart); + + distance = Distance(oldStart, mCurrentPosition); + + mSlidingBuffer->DiscardPrefix(mCurrentPosition); + mSlidingBuffer->BeginReading(mCurrentPosition); + mMarkPosition = mCurrentPosition; + } + + return distance; +} + +/** + * Insert data to our underlying input buffer as + * if it were read from an input stream. + * + * @update harishd 01/12/99 + * @return error code + */ +bool nsScanner::UngetReadable(const nsAString& aBuffer) { + if (!mSlidingBuffer) { + return false; + } + + mSlidingBuffer->UngetReadable(aBuffer, mCurrentPosition); + mSlidingBuffer->BeginReading( + mCurrentPosition); // Insertion invalidated our iterators + mSlidingBuffer->EndReading(mEndPosition); + + return true; +} + +/** + * Append data to our underlying input buffer as + * if it were read from an input stream. + * + * @update gess4/3/98 + * @return error code + */ +nsresult nsScanner::Append(const nsAString& aBuffer) { + if (!AppendToBuffer(aBuffer)) return NS_ERROR_OUT_OF_MEMORY; + return NS_OK; +} + +/** + * + * + * @update gess 5/21/98 + * @param + * @return + */ +nsresult nsScanner::Append(const char* aBuffer, uint32_t aLen) { + nsresult res = NS_OK; + if (mUnicodeDecoder) { + mozilla::CheckedInt<size_t> needed = + mUnicodeDecoder->MaxUTF16BufferLength(aLen); + if (!needed.isValid()) { + return NS_ERROR_OUT_OF_MEMORY; + } + mozilla::CheckedInt<uint32_t> allocLen( + 1); // null terminator due to legacy sadness + allocLen += needed.value(); + if (!allocLen.isValid()) { + return NS_ERROR_OUT_OF_MEMORY; + } + nsScannerString::Buffer* buffer = + nsScannerString::AllocBuffer(allocLen.value()); + NS_ENSURE_TRUE(buffer, NS_ERROR_OUT_OF_MEMORY); + char16_t* unichars = buffer->DataStart(); + + uint32_t result; + size_t read; + size_t written; + // Do not use structured binding lest deal with [-Werror=unused-variable] + std::tie(result, read, written) = + mUnicodeDecoder->DecodeToUTF16WithoutReplacement( + AsBytes(mozilla::Span(aBuffer, aLen)), + mozilla::Span(unichars, needed.value()), + false); // Retain bug about failure to handle EOF + MOZ_ASSERT(result != mozilla::kOutputFull); + MOZ_ASSERT(read <= aLen); + MOZ_ASSERT(written <= needed.value()); + if (result != mozilla::kInputEmpty) { + // Since about:blank is empty, this line runs only for XML. Use a + // character that's illegal in XML instead of U+FFFD in order to make + // expat flag the error. There is no need to loop and convert more, since + // expat will stop here anyway. + unichars[written++] = 0xFFFF; + } + buffer->SetDataLength(written); + // Don't propagate return code of unicode decoder + // since it doesn't reflect on our success or failure + // - Ref. bug 87110 + res = NS_OK; + AppendToBuffer(buffer); + } else { + NS_WARNING("No decoder found."); + res = NS_ERROR_FAILURE; + } + + return res; +} + +/** + * retrieve next char from scanners internal input stream + * + * @update gess 3/25/98 + * @param + * @return error code reflecting read status + */ +nsresult nsScanner::GetChar(char16_t& aChar) { + if (!mSlidingBuffer || mCurrentPosition == mEndPosition) { + aChar = 0; + return NS_ERROR_HTMLPARSER_EOF; + } + + aChar = *mCurrentPosition++; + + return NS_OK; +} + +void nsScanner::BindSubstring(nsScannerSubstring& aSubstring, + const nsScannerIterator& aStart, + const nsScannerIterator& aEnd) { + aSubstring.Rebind(*mSlidingBuffer, aStart, aEnd); +} + +void nsScanner::CurrentPosition(nsScannerIterator& aPosition) { + aPosition = mCurrentPosition; +} + +void nsScanner::EndReading(nsScannerIterator& aPosition) { + aPosition = mEndPosition; +} + +void nsScanner::SetPosition(nsScannerIterator& aPosition, bool aTerminate) { + if (mSlidingBuffer) { + mCurrentPosition = aPosition; + if (aTerminate && (mCurrentPosition == mEndPosition)) { + mMarkPosition = mCurrentPosition; + mSlidingBuffer->DiscardPrefix(mCurrentPosition); + } + } +} + +void nsScanner::AppendToBuffer(nsScannerString::Buffer* aBuf) { + if (!mSlidingBuffer) { + mSlidingBuffer = mozilla::MakeUnique<nsScannerString>(aBuf); + mSlidingBuffer->BeginReading(mCurrentPosition); + mMarkPosition = mCurrentPosition; + } else { + mSlidingBuffer->AppendBuffer(aBuf); + if (mCurrentPosition == mEndPosition) { + mSlidingBuffer->BeginReading(mCurrentPosition); + } + } + mSlidingBuffer->EndReading(mEndPosition); +} + +/** + * call this to copy bytes out of the scanner that have not yet been consumed + * by the tokenization process. + * + * @update gess 5/12/98 + * @param aCopyBuffer is where the scanner buffer will be copied to + * @return true if OK or false on OOM + */ +bool nsScanner::CopyUnusedData(nsString& aCopyBuffer) { + if (!mSlidingBuffer) { + aCopyBuffer.Truncate(); + return true; + } + + nsScannerIterator start, end; + start = mCurrentPosition; + end = mEndPosition; + + return CopyUnicodeTo(start, end, aCopyBuffer); +} + +/** + * Conduct self test. Actually, selftesting for this class + * occurs in the parser selftest. + * + * @update gess 3/25/98 + * @param + * @return + */ + +void nsScanner::SelfTest(void) { +#ifdef _DEBUG +#endif +} |