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diff --git a/chromium/third_party/libjingle/source/talk/base/safe_conversions_impl.h b/chromium/third_party/libjingle/source/talk/base/safe_conversions_impl.h
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+/*
+ * libjingle
+ * Copyright 2014, Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+// Borrowed from Chromium's src/base/numerics/safe_conversions_impl.h.
+
+#ifndef TALK_BASE_SAFE_CONVERSIONS_IMPL_H_
+#define TALK_BASE_SAFE_CONVERSIONS_IMPL_H_
+
+#include <limits>
+
+namespace talk_base {
+namespace internal {
+
+enum DstSign {
+  DST_UNSIGNED,
+  DST_SIGNED
+};
+
+enum SrcSign {
+  SRC_UNSIGNED,
+  SRC_SIGNED
+};
+
+enum DstRange {
+  OVERLAPS_RANGE,
+  CONTAINS_RANGE
+};
+
+// Helper templates to statically determine if our destination type can contain
+// all values represented by the source type.
+
+template <typename Dst, typename Src,
+          DstSign IsDstSigned = std::numeric_limits<Dst>::is_signed ?
+                                DST_SIGNED : DST_UNSIGNED,
+          SrcSign IsSrcSigned = std::numeric_limits<Src>::is_signed ?
+                                SRC_SIGNED : SRC_UNSIGNED>
+struct StaticRangeCheck {};
+
+template <typename Dst, typename Src>
+struct StaticRangeCheck<Dst, Src, DST_SIGNED, SRC_SIGNED> {
+  typedef std::numeric_limits<Dst> DstLimits;
+  typedef std::numeric_limits<Src> SrcLimits;
+  // Compare based on max_exponent, which we must compute for integrals.
+  static const size_t kDstMaxExponent = DstLimits::is_iec559 ?
+                                        DstLimits::max_exponent :
+                                        (sizeof(Dst) * 8 - 1);
+  static const size_t kSrcMaxExponent = SrcLimits::is_iec559 ?
+                                        SrcLimits::max_exponent :
+                                        (sizeof(Src) * 8 - 1);
+  static const DstRange value = kDstMaxExponent >= kSrcMaxExponent ?
+                                CONTAINS_RANGE : OVERLAPS_RANGE;
+};
+
+template <typename Dst, typename Src>
+struct StaticRangeCheck<Dst, Src, DST_UNSIGNED, SRC_UNSIGNED> {
+  static const DstRange value = sizeof(Dst) >= sizeof(Src) ?
+                                CONTAINS_RANGE : OVERLAPS_RANGE;
+};
+
+template <typename Dst, typename Src>
+struct StaticRangeCheck<Dst, Src, DST_SIGNED, SRC_UNSIGNED> {
+  typedef std::numeric_limits<Dst> DstLimits;
+  typedef std::numeric_limits<Src> SrcLimits;
+  // Compare based on max_exponent, which we must compute for integrals.
+  static const size_t kDstMaxExponent = DstLimits::is_iec559 ?
+                                        DstLimits::max_exponent :
+                                        (sizeof(Dst) * 8 - 1);
+  static const size_t kSrcMaxExponent = sizeof(Src) * 8;
+  static const DstRange value = kDstMaxExponent >= kSrcMaxExponent ?
+                                CONTAINS_RANGE : OVERLAPS_RANGE;
+};
+
+template <typename Dst, typename Src>
+struct StaticRangeCheck<Dst, Src, DST_UNSIGNED, SRC_SIGNED> {
+  static const DstRange value = OVERLAPS_RANGE;
+};
+
+
+enum RangeCheckResult {
+  TYPE_VALID = 0,      // Value can be represented by the destination type.
+  TYPE_UNDERFLOW = 1,  // Value would overflow.
+  TYPE_OVERFLOW = 2,   // Value would underflow.
+  TYPE_INVALID = 3     // Source value is invalid (i.e. NaN).
+};
+
+// This macro creates a RangeCheckResult from an upper and lower bound
+// check by taking advantage of the fact that only NaN can be out of range in
+// both directions at once.
+#define BASE_NUMERIC_RANGE_CHECK_RESULT(is_in_upper_bound, is_in_lower_bound) \
+    RangeCheckResult(((is_in_upper_bound) ? 0 : TYPE_OVERFLOW) | \
+                            ((is_in_lower_bound) ? 0 : TYPE_UNDERFLOW))
+
+template <typename Dst,
+          typename Src,
+          DstSign IsDstSigned = std::numeric_limits<Dst>::is_signed ?
+                                DST_SIGNED : DST_UNSIGNED,
+          SrcSign IsSrcSigned = std::numeric_limits<Src>::is_signed ?
+                                SRC_SIGNED : SRC_UNSIGNED,
+          DstRange IsSrcRangeContained = StaticRangeCheck<Dst, Src>::value>
+struct RangeCheckImpl {};
+
+// The following templates are for ranges that must be verified at runtime. We
+// split it into checks based on signedness to avoid confusing casts and
+// compiler warnings on signed an unsigned comparisons.
+
+// Dst range always contains the result: nothing to check.
+template <typename Dst, typename Src, DstSign IsDstSigned, SrcSign IsSrcSigned>
+struct RangeCheckImpl<Dst, Src, IsDstSigned, IsSrcSigned, CONTAINS_RANGE> {
+  static RangeCheckResult Check(Src value) {
+    return TYPE_VALID;
+  }
+};
+
+// Signed to signed narrowing.
+template <typename Dst, typename Src>
+struct RangeCheckImpl<Dst, Src, DST_SIGNED, SRC_SIGNED, OVERLAPS_RANGE> {
+  static RangeCheckResult Check(Src value) {
+    typedef std::numeric_limits<Dst> DstLimits;
+    return DstLimits::is_iec559 ?
+           BASE_NUMERIC_RANGE_CHECK_RESULT(
+               value <= static_cast<Src>(DstLimits::max()),
+               value >= static_cast<Src>(DstLimits::max() * -1)) :
+           BASE_NUMERIC_RANGE_CHECK_RESULT(
+               value <= static_cast<Src>(DstLimits::max()),
+               value >= static_cast<Src>(DstLimits::min()));
+  }
+};
+
+// Unsigned to unsigned narrowing.
+template <typename Dst, typename Src>
+struct RangeCheckImpl<Dst, Src, DST_UNSIGNED, SRC_UNSIGNED, OVERLAPS_RANGE> {
+  static RangeCheckResult Check(Src value) {
+    typedef std::numeric_limits<Dst> DstLimits;
+    return BASE_NUMERIC_RANGE_CHECK_RESULT(
+               value <= static_cast<Src>(DstLimits::max()), true);
+  }
+};
+
+// Unsigned to signed.
+template <typename Dst, typename Src>
+struct RangeCheckImpl<Dst, Src, DST_SIGNED, SRC_UNSIGNED, OVERLAPS_RANGE> {
+  static RangeCheckResult Check(Src value) {
+    typedef std::numeric_limits<Dst> DstLimits;
+    return sizeof(Dst) > sizeof(Src) ? TYPE_VALID :
+           BASE_NUMERIC_RANGE_CHECK_RESULT(
+               value <= static_cast<Src>(DstLimits::max()), true);
+  }
+};
+
+// Signed to unsigned.
+template <typename Dst, typename Src>
+struct RangeCheckImpl<Dst, Src, DST_UNSIGNED, SRC_SIGNED, OVERLAPS_RANGE> {
+  static RangeCheckResult Check(Src value) {
+    typedef std::numeric_limits<Dst> DstLimits;
+    typedef std::numeric_limits<Src> SrcLimits;
+    // Compare based on max_exponent, which we must compute for integrals.
+    static const size_t kDstMaxExponent = sizeof(Dst) * 8;
+    static const size_t kSrcMaxExponent = SrcLimits::is_iec559 ?
+                                          SrcLimits::max_exponent :
+                                          (sizeof(Src) * 8 - 1);
+    return (kDstMaxExponent >= kSrcMaxExponent) ?
+           BASE_NUMERIC_RANGE_CHECK_RESULT(true, value >= static_cast<Src>(0)) :
+           BASE_NUMERIC_RANGE_CHECK_RESULT(
+               value <= static_cast<Src>(DstLimits::max()),
+               value >= static_cast<Src>(0));
+  }
+};
+
+template <typename Dst, typename Src>
+inline RangeCheckResult RangeCheck(Src value) {
+  COMPILE_ASSERT(std::numeric_limits<Src>::is_specialized,
+                 argument_must_be_numeric);
+  COMPILE_ASSERT(std::numeric_limits<Dst>::is_specialized,
+                 result_must_be_numeric);
+  return RangeCheckImpl<Dst, Src>::Check(value);
+}
+
+}  // namespace internal
+}  // namespace talk_base
+
+#endif  // TALK_BASE_SAFE_CONVERSIONS_IMPL_H_