1 files changed, 151 insertions, 0 deletions
diff --git a/accessible/atk/DOMtoATK.cpp b/accessible/atk/DOMtoATK.cpp
new file mode 100644
index 0000000000..2c23731bba
--- /dev/null
+++ b/accessible/atk/DOMtoATK.cpp
@@ -0,0 +1,151 @@
+/* -*- 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 >= 0 && *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());
+}
+
+}  // namespace DOMtoATK
+
+}  // namespace a11y
+}  // namespace mozilla