1 files changed, 120 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/regeximp.cpp b/intl/icu/source/i18n/regeximp.cpp
new file mode 100644
index 0000000000..86e238c0f7
--- /dev/null
+++ b/intl/icu/source/i18n/regeximp.cpp
@@ -0,0 +1,120 @@
+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+//
+//   Copyright (C) 2012 International Business Machines Corporation
+//   and others. All rights reserved.
+//
+//   file:  regeximp.cpp
+//
+//           ICU Regular Expressions,
+//             miscellaneous implementation functions.
+//
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_REGULAR_EXPRESSIONS
+#include "regeximp.h"
+#include "unicode/utf16.h"
+
+U_NAMESPACE_BEGIN
+
+CaseFoldingUTextIterator::CaseFoldingUTextIterator(UText &text) :
+   fUText(text), fFoldChars(nullptr), fFoldLength(0) {
+}
+
+CaseFoldingUTextIterator::~CaseFoldingUTextIterator() {}
+
+UChar32 CaseFoldingUTextIterator::next() {
+    UChar32  foldedC;
+    UChar32  originalC;
+    if (fFoldChars == nullptr) {
+        // We are not in a string folding of an earlier character.
+        // Start handling the next char from the input UText.
+        originalC = UTEXT_NEXT32(&fUText);
+        if (originalC == U_SENTINEL) {
+            return originalC;
+        }
+        fFoldLength = ucase_toFullFolding(originalC, &fFoldChars, U_FOLD_CASE_DEFAULT);
+        if (fFoldLength >= UCASE_MAX_STRING_LENGTH || fFoldLength < 0) {
+            // input code point folds to a single code point, possibly itself.
+            // See comment in ucase.h for explanation of return values from ucase_toFullFoldings.
+            if (fFoldLength < 0) {
+                fFoldLength = ~fFoldLength;
+            }
+            foldedC = (UChar32)fFoldLength;
+            fFoldChars = nullptr;
+            return foldedC;
+        }
+        // String foldings fall through here.
+        fFoldIndex = 0;
+    }
+
+    U16_NEXT(fFoldChars, fFoldIndex, fFoldLength, foldedC);
+    if (fFoldIndex >= fFoldLength) {
+        fFoldChars = nullptr;
+    }
+    return foldedC;
+}
+    
+
+UBool CaseFoldingUTextIterator::inExpansion() {
+    return fFoldChars != nullptr;
+}
+
+
+
+CaseFoldingUCharIterator::CaseFoldingUCharIterator(const char16_t *chars, int64_t start, int64_t limit) :
+   fChars(chars), fIndex(start), fLimit(limit), fFoldChars(nullptr), fFoldLength(0) {
+}
+
+
+CaseFoldingUCharIterator::~CaseFoldingUCharIterator() {}
+
+
+UChar32 CaseFoldingUCharIterator::next() {
+    UChar32  foldedC;
+    UChar32  originalC;
+    if (fFoldChars == nullptr) {
+        // We are not in a string folding of an earlier character.
+        // Start handling the next char from the input UText.
+        if (fIndex >= fLimit) {
+            return U_SENTINEL;
+        }
+        U16_NEXT(fChars, fIndex, fLimit, originalC);
+
+        fFoldLength = ucase_toFullFolding(originalC, &fFoldChars, U_FOLD_CASE_DEFAULT);
+        if (fFoldLength >= UCASE_MAX_STRING_LENGTH || fFoldLength < 0) {
+            // input code point folds to a single code point, possibly itself.
+            // See comment in ucase.h for explanation of return values from ucase_toFullFoldings.
+            if (fFoldLength < 0) {
+                fFoldLength = ~fFoldLength;
+            }
+            foldedC = (UChar32)fFoldLength;
+            fFoldChars = nullptr;
+            return foldedC;
+        }
+        // String foldings fall through here.
+        fFoldIndex = 0;
+    }
+
+    U16_NEXT(fFoldChars, fFoldIndex, fFoldLength, foldedC);
+    if (fFoldIndex >= fFoldLength) {
+        fFoldChars = nullptr;
+    }
+    return foldedC;
+}
+    
+
+UBool CaseFoldingUCharIterator::inExpansion() {
+    return fFoldChars != nullptr;
+}
+
+int64_t CaseFoldingUCharIterator::getIndex() {
+    return fIndex;
+}
+
+
+U_NAMESPACE_END
+
+#endif
+