1 files changed, 194 insertions, 0 deletions
diff --git a/dom/xslt/base/txDouble.cpp b/dom/xslt/base/txDouble.cpp
new file mode 100644
index 0000000000..ad7fa690be
--- /dev/null
+++ b/dom/xslt/base/txDouble.cpp
@@ -0,0 +1,194 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 "mozilla/FloatingPoint.h"
+
+#include "nsString.h"
+#include "txCore.h"
+#include "txXMLUtils.h"
+#include <math.h>
+#include <stdlib.h>
+#include <algorithm>
+#ifdef WIN32
+#  include <float.h>
+#endif
+#include "prdtoa.h"
+
+/*
+ * Utility class for doubles
+ */
+
+/*
+ * Converts the given String to a double, if the String value does not
+ * represent a double, NaN will be returned
+ */
+class txStringToDouble {
+ public:
+  txStringToDouble() : mState(eWhitestart), mSign(ePositive) {}
+
+  void Parse(const nsAString& aSource) {
+    if (mState == eIllegal) {
+      return;
+    }
+    uint32_t i = 0;
+    char16_t c;
+    auto len = aSource.Length();
+    for (; i < len; ++i) {
+      c = aSource[i];
+      switch (mState) {
+        case eWhitestart:
+          if (c == '-') {
+            mState = eDecimal;
+            mSign = eNegative;
+          } else if (c >= '0' && c <= '9') {
+            mState = eDecimal;
+            mBuffer.Append((char)c);
+          } else if (c == '.') {
+            mState = eMantissa;
+            mBuffer.Append((char)c);
+          } else if (!XMLUtils::isWhitespace(c)) {
+            mState = eIllegal;
+            return;
+          }
+          break;
+        case eDecimal:
+          if (c >= '0' && c <= '9') {
+            mBuffer.Append((char)c);
+          } else if (c == '.') {
+            mState = eMantissa;
+            mBuffer.Append((char)c);
+          } else if (XMLUtils::isWhitespace(c)) {
+            mState = eWhiteend;
+          } else {
+            mState = eIllegal;
+            return;
+          }
+          break;
+        case eMantissa:
+          if (c >= '0' && c <= '9') {
+            mBuffer.Append((char)c);
+          } else if (XMLUtils::isWhitespace(c)) {
+            mState = eWhiteend;
+          } else {
+            mState = eIllegal;
+            return;
+          }
+          break;
+        case eWhiteend:
+          if (!XMLUtils::isWhitespace(c)) {
+            mState = eIllegal;
+            return;
+          }
+          break;
+        default:
+          break;
+      }
+    }
+  }
+
+  double getDouble() {
+    if (mState == eIllegal || mBuffer.IsEmpty() ||
+        (mBuffer.Length() == 1 && mBuffer[0] == '.')) {
+      return mozilla::UnspecifiedNaN<double>();
+    }
+    return static_cast<double>(mSign) * PR_strtod(mBuffer.get(), nullptr);
+  }
+
+ private:
+  nsAutoCString mBuffer;
+  enum { eWhitestart, eDecimal, eMantissa, eWhiteend, eIllegal } mState;
+  enum { eNegative = -1, ePositive = 1 } mSign;
+};
+
+double txDouble::toDouble(const nsAString& aSrc) {
+  txStringToDouble sink;
+  sink.Parse(aSrc);
+  return sink.getDouble();
+}
+
+/*
+ * Converts the value of the given double to a String, and places
+ * The result into the destination String.
+ * @return the given dest string
+ */
+void txDouble::toString(double aValue, nsAString& aDest) {
+  // check for special cases
+
+  if (std::isnan(aValue)) {
+    aDest.AppendLiteral("NaN");
+    return;
+  }
+  if (std::isinf(aValue)) {
+    if (aValue < 0) aDest.Append(char16_t('-'));
+    aDest.AppendLiteral("Infinity");
+    return;
+  }
+
+  // Mantissa length is 17, so this is plenty
+  const int buflen = 20;
+  char buf[buflen];
+
+  int intDigits, sign;
+  char* endp;
+  PR_dtoa(aValue, 0, 0, &intDigits, &sign, &endp, buf, buflen - 1);
+
+  // compute length
+  int32_t length = endp - buf;
+  if (length > intDigits) {
+    // decimal point needed
+    ++length;
+    if (intDigits < 1) {
+      // leading zeros, -intDigits + 1
+      length += 1 - intDigits;
+    }
+  } else {
+    // trailing zeros, total length given by intDigits
+    length = intDigits;
+  }
+  if (aValue < 0) ++length;
+  // grow the string
+  uint32_t oldlength = aDest.Length();
+  if (!aDest.SetLength(oldlength + length, mozilla::fallible))
+    return;  // out of memory
+  auto dest = aDest.BeginWriting();
+  std::advance(dest, oldlength);
+  if (aValue < 0) {
+    *dest = '-';
+    ++dest;
+  }
+  int i;
+  // leading zeros
+  if (intDigits < 1) {
+    *dest = '0';
+    ++dest;
+    *dest = '.';
+    ++dest;
+    for (i = 0; i > intDigits; --i) {
+      *dest = '0';
+      ++dest;
+    }
+  }
+  // mantissa
+  int firstlen = std::min<size_t>(intDigits, endp - buf);
+  for (i = 0; i < firstlen; i++) {
+    *dest = buf[i];
+    ++dest;
+  }
+  if (i < endp - buf) {
+    if (i > 0) {
+      *dest = '.';
+      ++dest;
+    }
+    for (; i < endp - buf; i++) {
+      *dest = buf[i];
+      ++dest;
+    }
+  }
+  // trailing zeros
+  for (; i < intDigits; i++) {
+    *dest = '0';
+    ++dest;
+  }
+}