gecko-dev/accessible/atk/DOMtoATK.cpp

162 строки
4.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* 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/. */
#include "DOMtoATK.h"
#include "nsUTF8Utils.h"
namespace mozilla {
namespace a11y {
namespace DOMtoATK {
void
AddBOMs(nsACString& aDest, const nsACString& aSource)
{
uint32_t destlength = 0;
// First compute how much room we will need.
for (uint32_t srci = 0; srci < aSource.Length(); ) {
int bytes = UTF8traits::bytes(aSource[srci]);
if (bytes >= 4) {
// Non-BMP character, will add a BOM after it.
destlength += 3;
}
// Skip whole character encoding.
srci += bytes;
destlength += bytes;
}
uint32_t desti = 0; // Index within aDest.
// Add BOMs after non-BMP characters.
aDest.SetLength(destlength);
for (uint32_t srci = 0; srci < aSource.Length(); ) {
uint32_t bytes = UTF8traits::bytes(aSource[srci]);
MOZ_ASSERT(bytes <= aSource.Length() - srci, "We should have the whole sequence");
// Copy whole sequence.
aDest.Replace(desti, bytes, Substring(aSource, srci, bytes));
desti += bytes;
srci += bytes;
if (bytes >= 4) {
// More than 4 bytes in UTF-8 encoding exactly means more than 16 encoded
// bits. This is thus a non-BMP character which needed a surrogate
// pair to get encoded in UTF-16, add a BOM after it.
// And add a BOM after it.
aDest.Replace(desti, 3, "\xEF\xBB\xBF");
desti += 3;
}
}
MOZ_ASSERT(desti == destlength, "Incoherency between computed length"
"and actually translated length");
}
void
ATKStringConverterHelper::AdjustOffsets(gint* aStartOffset, gint* aEndOffset,
gint count)
{
MOZ_ASSERT(!mAdjusted, "DOMtoATK::ATKStringConverterHelper::AdjustOffsets needs to be called only once");
if (*aStartOffset > 0) {
(*aStartOffset)--;
mStartShifted = true;
}
if (*aEndOffset != -1 && *aEndOffset < count) {
(*aEndOffset)++;
mEndShifted = true;
}
#ifdef DEBUG
mAdjusted = true;
#endif
}
gchar*
ATKStringConverterHelper::FinishUTF16toUTF8(nsCString& aStr)
{
int skip = 0;
if (mStartShifted) {
// AdjustOffsets added a leading character.
MOZ_ASSERT(aStr.Length() > 0, "There should be a leading character");
MOZ_ASSERT(static_cast<int>(aStr.Length()) >= UTF8traits::bytes(aStr.CharAt(0)),
"The leading character should be complete");
// drop first character
skip = UTF8traits::bytes(aStr.CharAt(0));
}
if (mEndShifted) {
// AdjustOffsets added a trailing character.
MOZ_ASSERT(aStr.Length() > 0, "There should be a trailing character");
int trail = -1;
// Find beginning of last character.
for (trail = aStr.Length() - 1; trail >= 0; trail--) {
if (!UTF8traits::isInSeq(aStr.CharAt(trail))) {
break;
}
}
MOZ_ASSERT(trail >= 0,
"There should be at least a whole trailing character");
MOZ_ASSERT(trail + UTF8traits::bytes(aStr.CharAt(trail)) == static_cast<int>(aStr.Length()),
"The trailing character should be complete");
// Drop the last character.
aStr.Truncate(trail);
}
// copy and return, libspi will free it
return g_strdup(aStr.get() + skip);
}
gchar*
ATKStringConverterHelper::ConvertAdjusted(const nsAString& aStr)
{
MOZ_ASSERT(mAdjusted, "DOMtoATK::ATKStringConverterHelper::AdjustOffsets needs to be called before ATKStringConverterHelper::ConvertAdjusted");
NS_ConvertUTF16toUTF8 cautoStr(aStr);
if (!cautoStr.get()) {
return nullptr;
}
nsAutoCString cautoStrBOMs;
AddBOMs(cautoStrBOMs, cautoStr);
return FinishUTF16toUTF8(cautoStrBOMs);
}
gchar*
Convert(const nsAString& aStr)
{
NS_ConvertUTF16toUTF8 cautoStr(aStr);
if (!cautoStr.get()) {
return nullptr;
}
nsAutoCString cautoStrBOMs;
AddBOMs(cautoStrBOMs, cautoStr);
return g_strdup(cautoStrBOMs.get());
}
void
ConvertTexttoAsterisks(nsAString& aString)
{
for (uint32_t i = 0; i < aString.Length(); i++) {
aString.ReplaceLiteral(i, 1, u"*");
}
}
}
} // namespace a11y
} // namespace mozilla