The Tor Browser: comparison content/base/src/nsTextFragment.h

--1:000000000000
+:41426a501f46
+/* 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/. */
+/*
+* A class which represents a fragment of text (eg inside a text
+* node); if only codepoints below 256 are used, the text is stored as
+* a char*; otherwise the text is stored as a char16_t*
+*/
+#ifndef nsTextFragment_h___
+#define nsTextFragment_h___
+#include "mozilla/Attributes.h"
+#include "mozilla/MemoryReporting.h"
+#include "nsString.h"
+#include "nsReadableUtils.h"
+#include "nsISupportsImpl.h"
+class nsString;
+class nsCString;
+// XXX should this normalize the code to keep a \u0000 at the end?
+// XXX nsTextFragmentPool?
+/**
+* A fragment of text. If mIs2b is 1 then the m2b pointer is valid
+* otherwise the m1b pointer is valid. If m1b is used then each byte
+* of data represents a single ucs2 character with the high byte being
+* zero.
+*
+* This class does not have a virtual destructor therefore it is not
+* meant to be subclassed.
+*/
+class nsTextFragment MOZ_FINAL {
+public:
+static nsresult Init();
+static void Shutdown();
+/**
+* Default constructor. Initialize the fragment to be empty.
+*/
+nsTextFragment()
+: m1b(nullptr), mAllBits(0)
+{
+MOZ_COUNT_CTOR(nsTextFragment);
+NS_ASSERTION(sizeof(FragmentBits) == 4, "Bad field packing!");
+}
+~nsTextFragment();
+/**
+* Change the contents of this fragment to be a copy of the
+* the argument fragment, or to "" if unable to allocate enough memory.
+*/
+nsTextFragment& operator=(const nsTextFragment& aOther);
+/**
+* Return true if this fragment is represented by char16_t data
+*/
+bool Is2b() const
+{
+return mState.mIs2b;
+}
+/**
+* Return true if this fragment contains Bidi text
+* For performance reasons this flag is only set if explicitely requested (by
+* setting the aUpdateBidi argument on SetTo or Append to true).
+*/
+bool IsBidi() const
+{
+return mState.mIsBidi;
+}
+/**
+* Get a pointer to constant char16_t data.
+*/
+const char16_t *Get2b() const
+{
+NS_ASSERTION(Is2b(), "not 2b text");
+return m2b;
+}
+/**
+* Get a pointer to constant char data.
+*/
+const char *Get1b() const
+{
+NS_ASSERTION(!Is2b(), "not 1b text");
+return (const char *)m1b;
+}
+/**
+* Get the length of the fragment. The length is the number of logical
+* characters, not the number of bytes to store the characters.
+*/
+uint32_t GetLength() const
+{
+return mState.mLength;
+}
+bool CanGrowBy(size_t n) const
+{
+return n < (1 << 29) && mState.mLength + n < (1 << 29);
+}
+/**
+* Change the contents of this fragment to be a copy of the given
+* buffer. If aUpdateBidi is true, contents of the fragment will be scanned,
+* and mState.mIsBidi will be turned on if it includes any Bidi characters.
+*/
+bool SetTo(const char16_t* aBuffer, int32_t aLength, bool aUpdateBidi);
+/**
+* Append aData to the end of this fragment. If aUpdateBidi is true, contents
+* of the fragment will be scanned, and mState.mIsBidi will be turned on if
+* it includes any Bidi characters.
+*/
+bool Append(const char16_t* aBuffer, uint32_t aLength, bool aUpdateBidi);
+/**
+* Append the contents of this string fragment to aString
+*/
+void AppendTo(nsAString& aString) const {
+if (!AppendTo(aString, mozilla::fallible_t())) {
+NS_ABORT_OOM(GetLength());
+}
+}
+/**
+* Append the contents of this string fragment to aString
+* @return false if an out of memory condition is detected, true otherwise
+*/
+bool AppendTo(nsAString& aString,
+const mozilla::fallible_t&) const NS_WARN_UNUSED_RESULT {
+if (mState.mIs2b) {
+bool ok = aString.Append(m2b, mState.mLength, mozilla::fallible_t());
+if (!ok) {
+return false;
+}
+return true;
+} else {
+return AppendASCIItoUTF16(Substring(m1b, mState.mLength), aString,
+mozilla::fallible_t());
+}
+}
+/**
+* Append a substring of the contents of this string fragment to aString.
+* @param aOffset where to start the substring in this text fragment
+* @param aLength the length of the substring
+*/
+void AppendTo(nsAString& aString, int32_t aOffset, int32_t aLength) const {
+if (!AppendTo(aString, aOffset, aLength, mozilla::fallible_t())) {
+NS_ABORT_OOM(aLength);
+}
+}
+/**
+* Append a substring of the contents of this string fragment to aString.
+* @param aString the string in which to append
+* @param aOffset where to start the substring in this text fragment
+* @param aLength the length of the substring
+* @return false if an out of memory condition is detected, true otherwise
+*/
+bool AppendTo(nsAString& aString, int32_t aOffset, int32_t aLength,
+const mozilla::fallible_t&) const NS_WARN_UNUSED_RESULT
+{
+if (mState.mIs2b) {
+bool ok = aString.Append(m2b + aOffset, aLength, mozilla::fallible_t());
+if (!ok) {
+return false;
+}
+return true;
+} else {
+return AppendASCIItoUTF16(Substring(m1b + aOffset, aLength), aString,
+mozilla::fallible_t());
+}
+}
+/**
+* Make a copy of the fragments contents starting at offset for
+* count characters. The offset and count will be adjusted to
+* lie within the fragments data. The fragments data is converted if
+* necessary.
+*/
+void CopyTo(char16_t *aDest, int32_t aOffset, int32_t aCount);
+/**
+* Return the character in the text-fragment at the given
+* index. This always returns a char16_t.
+*/
+char16_t CharAt(int32_t aIndex) const
+{
+NS_ASSERTION(uint32_t(aIndex) < mState.mLength, "bad index");
+return mState.mIs2b ? m2b[aIndex] : static_cast<unsigned char>(m1b[aIndex]);
+}
+struct FragmentBits {
+// uint32_t to ensure that the values are unsigned, because we
+// want 0/1, not 0/-1!
+// Making these bool causes Windows to not actually pack them,
+// which causes crashes because we assume this structure is no more than
+// 32 bits!
+uint32_t mInHeap : 1;
+uint32_t mIs2b : 1;
+uint32_t mIsBidi : 1;
+uint32_t mLength : 29;
+};
+size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
+private:
+void ReleaseText();
+/**
+* Scan the contents of the fragment and turn on mState.mIsBidi if it
+* includes any Bidi characters.
+*/
+void UpdateBidiFlag(const char16_t* aBuffer, uint32_t aLength);
+union {
+char16_t *m2b;
+const char *m1b; // This is const since it can point to shared data
+};
+union {
+uint32_t mAllBits;
+FragmentBits mState;
+};
+};
+#endif /* nsTextFragment_h___ */

The Tor Browser / file comparison

comparison: content/base/src/nsTextFragment.h

content/base/src/nsTextFragment.h