gecko-dev/content/base/src/nsTextFragment.cpp

370 lines
8.9 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** 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 Communicator client code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* 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 ***** */
#include "nsTextFragment.h"
#include "nsString.h"
#include "nsCRT.h"
#include "nsReadableUtils.h"
#include "nsMemory.h"
#include "nsBidiUtils.h"
#include "nsUnicharUtils.h"
// Static buffer used for newline fragments
static unsigned char sNewLineCharacter = '\n';
nsTextFragment::~nsTextFragment()
{
ReleaseText();
}
void
nsTextFragment::ReleaseText()
{
if (mState.mLength && m1b && mState.mInHeap) {
unsigned char *buf = NS_CONST_CAST(unsigned char *, m1b);
nsMemory::Free(buf); // m1b == m2b as far as nsMemory is concerned
}
m1b = nsnull;
// Set mState.mIs2b, mState.mInHeap, and mState.mLength = 0 with mAllBits;
mAllBits = 0;
}
nsTextFragment::nsTextFragment(const nsTextFragment& aOther)
: m1b(nsnull), mAllBits(0)
{
if (aOther.Is2b()) {
SetTo(aOther.Get2b(), aOther.GetLength());
} else {
SetTo(aOther.Get1b(), aOther.GetLength());
}
}
nsTextFragment::nsTextFragment(const char *aString)
: m1b(nsnull), mAllBits(0)
{
SetTo(aString, strlen(aString));
}
nsTextFragment::nsTextFragment(const PRUnichar *aString)
: m1b(nsnull), mAllBits(0)
{
SetTo(aString, nsCRT::strlen(aString));
}
nsTextFragment::nsTextFragment(const nsString& aString)
: m1b(nsnull), mAllBits(0)
{
SetTo(aString.get(), aString.Length());
}
nsTextFragment&
nsTextFragment::operator=(const nsTextFragment& aOther)
{
if (aOther.Is2b()) {
SetTo(aOther.Get2b(), aOther.GetLength());
} else {
SetTo(aOther.Get1b(), aOther.GetLength());
}
if (aOther.mState.mIsBidi) {
// Carry over BIDI state from aOther
mState.mIsBidi = PR_TRUE;
}
return *this;
}
nsTextFragment&
nsTextFragment::operator=(const char *aString)
{
SetTo(aString, strlen(aString));
return *this;
}
nsTextFragment&
nsTextFragment::operator=(const PRUnichar *aString)
{
SetTo(aString, nsCRT::strlen(aString));
return *this;
}
nsTextFragment&
nsTextFragment::operator=(const nsAString& aString)
{
ReleaseText();
PRUint32 length = aString.Length();
if (length > 0) {
PRBool in_heap = PR_TRUE;
if (IsASCII(aString)) {
if (length == 1 && aString.First() == '\n') {
m1b = &sNewLineCharacter;
in_heap = PR_FALSE;
} else {
m1b = (unsigned char *)ToNewCString(aString);
}
mState.mIs2b = PR_FALSE;
} else {
m2b = ToNewUnicode(aString);
mState.mIs2b = PR_TRUE;
}
mState.mInHeap = in_heap;
mState.mLength = length;
}
return *this;
}
void
nsTextFragment::SetTo(PRUnichar *aBuffer, PRInt32 aLength, PRBool aRelease)
{
ReleaseText();
m2b = aBuffer;
mState.mIs2b = PR_TRUE;
mState.mInHeap = aRelease;
mState.mLength = aLength;
}
void
nsTextFragment::SetTo(const PRUnichar* aBuffer, PRInt32 aLength)
{
ReleaseText();
if (aLength != 0) {
// See if we need to store the data in ucs2 or not
PRBool need2 = PR_FALSE;
const PRUnichar *ucp = aBuffer;
const PRUnichar *uend = aBuffer + aLength;
while (ucp < uend) {
PRUnichar ch = *ucp++;
if (ch >> 8) {
need2 = PR_TRUE;
break;
}
}
if (need2) {
// Use ucs2 storage because we have to
m2b = (const PRUnichar *)nsMemory::Clone(aBuffer,
aLength * sizeof(PRUnichar));
if (!m2b) {
NS_ERROR("Failed to clone string buffer!");
return;
}
// Setup our fields
mState.mIs2b = PR_TRUE;
mState.mInHeap = PR_TRUE;
mState.mLength = aLength;
} else {
// Use 1 byte storage because we can
PRBool in_heap = PR_TRUE;
if (aLength == 1 && *aBuffer == '\n') {
m1b = &sNewLineCharacter;
in_heap = PR_FALSE;
} else {
unsigned char *nt =
(unsigned char *)nsMemory::Alloc(aLength * sizeof(char));
if (!nt) {
NS_ERROR("Failed to allocate string buffer!");
return;
}
// Copy data
for (PRUint32 i = 0; i < (PRUint32)aLength; ++i) {
nt[i] = (unsigned char)aBuffer[i];
}
m1b = nt;
}
// Setup our fields
mState.mIs2b = PR_FALSE;
mState.mInHeap = in_heap;
mState.mLength = aLength;
}
}
}
void
nsTextFragment::SetTo(const char *aBuffer, PRInt32 aLength)
{
ReleaseText();
if (aLength != 0) {
PRBool in_heap = PR_TRUE;
if (aLength == 1 && *aBuffer == '\n') {
m1b = &sNewLineCharacter;
in_heap = PR_FALSE;
} else {
m1b = (unsigned char *)nsMemory::Clone(aBuffer, aLength * sizeof(char));
if (!m1b) {
NS_ERROR("Failed to allocate string buffer!");
return;
}
}
// Setup our fields
mState.mIs2b = PR_FALSE;
mState.mInHeap = in_heap;
mState.mLength = aLength;
}
}
void
nsTextFragment::AppendTo(nsAString& aString) const
{
if (mState.mIs2b) {
aString.Append(m2b, mState.mLength);
} else {
AppendASCIItoUTF16(Substring((char *)m1b, ((char *)m1b) + mState.mLength),
aString);
}
}
void
nsTextFragment::AppendTo(nsACString& aCString) const
{
if (mState.mIs2b) {
LossyAppendUTF16toASCII(Substring((PRUnichar *)m2b,
(PRUnichar *)m2b + mState.mLength),
aCString);
} else {
aCString.Append((char *)m1b, mState.mLength);
}
}
void
nsTextFragment::CopyTo(PRUnichar *aDest, PRInt32 aOffset, PRInt32 aCount)
{
NS_ASSERTION(aOffset >= 0, "Bad offset passed to nsTextFragment::CopyTo()!");
NS_ASSERTION(aCount >= 0, "Bad count passed to nsTextFragment::CopyTo()!");
if (aOffset < 0) {
aOffset = 0;
}
if (aOffset + aCount > GetLength()) {
aCount = mState.mLength - aOffset;
}
if (aCount != 0) {
if (mState.mIs2b) {
memcpy(aDest, m2b + aOffset, sizeof(PRUnichar) * aCount);
} else {
unsigned const char *cp = m1b + aOffset;
unsigned const char *end = cp + aCount;
while (cp < end) {
*aDest++ = PRUnichar(*cp++);
}
}
}
}
void
nsTextFragment::CopyTo(char *aDest, PRInt32 aOffset, PRInt32 aCount)
{
NS_ASSERTION(aOffset >= 0, "Bad offset passed to nsTextFragment::CopyTo()!");
NS_ASSERTION(aCount >= 0, "Bad count passed to nsTextFragment::CopyTo()!");
if (aOffset < 0) {
aOffset = 0;
}
if (aOffset + aCount > GetLength()) {
aCount = mState.mLength - aOffset;
}
if (aCount != 0) {
if (mState.mIs2b) {
const PRUnichar *cp = m2b + aOffset;
const PRUnichar *end = cp + aCount;
while (cp < end) {
*aDest++ = (char)(*cp++);
}
} else {
memcpy(aDest, m1b + aOffset, sizeof(char) * aCount);
}
}
}
// To save time we only do this when we really want to know, not during
// every allocation
void
nsTextFragment::SetBidiFlag()
{
if (mState.mIs2b && !mState.mIsBidi) {
const PRUnichar* cp = m2b;
const PRUnichar* end = cp + mState.mLength;
while (cp < end) {
PRUnichar ch1 = *cp++;
PRUint32 utf32Char = ch1;
if (IS_HIGH_SURROGATE(ch1) &&
cp < end &&
IS_LOW_SURROGATE(*cp)) {
PRUnichar ch2 = *cp++;
utf32Char = SURROGATE_TO_UCS4(ch1, ch2);
}
if (UTF32_CHAR_IS_BIDI(utf32Char) || IS_BIDI_CONTROL_CHAR(utf32Char)) {
mState.mIsBidi = PR_TRUE;
break;
}
}
}
}