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-rw-r--r--security/sandbox/chromium/base/numerics/safe_conversions_impl.h264
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diff --git a/security/sandbox/chromium/base/numerics/safe_conversions_impl.h b/security/sandbox/chromium/base/numerics/safe_conversions_impl.h
deleted file mode 100644
index 02e68e25d..000000000
--- a/security/sandbox/chromium/base/numerics/safe_conversions_impl.h
+++ /dev/null
@@ -1,264 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef BASE_NUMERICS_SAFE_CONVERSIONS_IMPL_H_
-#define BASE_NUMERICS_SAFE_CONVERSIONS_IMPL_H_
-
-#include <limits.h>
-#include <stdint.h>
-
-#include <limits>
-
-#include "base/template_util.h"
-
-namespace base {
-namespace internal {
-
-// The std library doesn't provide a binary max_exponent for integers, however
-// we can compute one by adding one to the number of non-sign bits. This allows
-// for accurate range comparisons between floating point and integer types.
-template <typename NumericType>
-struct MaxExponent {
- static const int value = std::numeric_limits<NumericType>::is_iec559
- ? std::numeric_limits<NumericType>::max_exponent
- : (sizeof(NumericType) * 8 + 1 -
- std::numeric_limits<NumericType>::is_signed);
-};
-
-enum IntegerRepresentation {
- INTEGER_REPRESENTATION_UNSIGNED,
- INTEGER_REPRESENTATION_SIGNED
-};
-
-// A range for a given nunmeric Src type is contained for a given numeric Dst
-// type if both numeric_limits<Src>::max() <= numeric_limits<Dst>::max() and
-// numeric_limits<Src>::min() >= numeric_limits<Dst>::min() are true.
-// We implement this as template specializations rather than simple static
-// comparisons to ensure type correctness in our comparisons.
-enum NumericRangeRepresentation {
- NUMERIC_RANGE_NOT_CONTAINED,
- NUMERIC_RANGE_CONTAINED
-};
-
-// Helper templates to statically determine if our destination type can contain
-// maximum and minimum values represented by the source type.
-
-template <
- typename Dst,
- typename Src,
- IntegerRepresentation DstSign = std::numeric_limits<Dst>::is_signed
- ? INTEGER_REPRESENTATION_SIGNED
- : INTEGER_REPRESENTATION_UNSIGNED,
- IntegerRepresentation SrcSign =
- std::numeric_limits<Src>::is_signed
- ? INTEGER_REPRESENTATION_SIGNED
- : INTEGER_REPRESENTATION_UNSIGNED >
-struct StaticDstRangeRelationToSrcRange;
-
-// Same sign: Dst is guaranteed to contain Src only if its range is equal or
-// larger.
-template <typename Dst, typename Src, IntegerRepresentation Sign>
-struct StaticDstRangeRelationToSrcRange<Dst, Src, Sign, Sign> {
- static const NumericRangeRepresentation value =
- MaxExponent<Dst>::value >= MaxExponent<Src>::value
- ? NUMERIC_RANGE_CONTAINED
- : NUMERIC_RANGE_NOT_CONTAINED;
-};
-
-// Unsigned to signed: Dst is guaranteed to contain source only if its range is
-// larger.
-template <typename Dst, typename Src>
-struct StaticDstRangeRelationToSrcRange<Dst,
- Src,
- INTEGER_REPRESENTATION_SIGNED,
- INTEGER_REPRESENTATION_UNSIGNED> {
- static const NumericRangeRepresentation value =
- MaxExponent<Dst>::value > MaxExponent<Src>::value
- ? NUMERIC_RANGE_CONTAINED
- : NUMERIC_RANGE_NOT_CONTAINED;
-};
-
-// Signed to unsigned: Dst cannot be statically determined to contain Src.
-template <typename Dst, typename Src>
-struct StaticDstRangeRelationToSrcRange<Dst,
- Src,
- INTEGER_REPRESENTATION_UNSIGNED,
- INTEGER_REPRESENTATION_SIGNED> {
- static const NumericRangeRepresentation value = NUMERIC_RANGE_NOT_CONTAINED;
-};
-
-enum RangeConstraint {
- RANGE_VALID = 0x0, // Value can be represented by the destination type.
- RANGE_UNDERFLOW = 0x1, // Value would overflow.
- RANGE_OVERFLOW = 0x2, // Value would underflow.
- RANGE_INVALID = RANGE_UNDERFLOW | RANGE_OVERFLOW // Invalid (i.e. NaN).
-};
-
-// Helper function for coercing an int back to a RangeContraint.
-inline RangeConstraint GetRangeConstraint(int integer_range_constraint) {
- DCHECK(integer_range_constraint >= RANGE_VALID &&
- integer_range_constraint <= RANGE_INVALID);
- return static_cast<RangeConstraint>(integer_range_constraint);
-}
-
-// This function creates a RangeConstraint 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.
-inline RangeConstraint GetRangeConstraint(bool is_in_upper_bound,
- bool is_in_lower_bound) {
- return GetRangeConstraint((is_in_upper_bound ? 0 : RANGE_OVERFLOW) |
- (is_in_lower_bound ? 0 : RANGE_UNDERFLOW));
-}
-
-// The following helper template addresses a corner case in range checks for
-// conversion from a floating-point type to an integral type of smaller range
-// but larger precision (e.g. float -> unsigned). The problem is as follows:
-// 1. Integral maximum is always one less than a power of two, so it must be
-// truncated to fit the mantissa of the floating point. The direction of
-// rounding is implementation defined, but by default it's always IEEE
-// floats, which round to nearest and thus result in a value of larger
-// magnitude than the integral value.
-// Example: float f = UINT_MAX; // f is 4294967296f but UINT_MAX
-// // is 4294967295u.
-// 2. If the floating point value is equal to the promoted integral maximum
-// value, a range check will erroneously pass.
-// Example: (4294967296f <= 4294967295u) // This is true due to a precision
-// // loss in rounding up to float.
-// 3. When the floating point value is then converted to an integral, the
-// resulting value is out of range for the target integral type and
-// thus is implementation defined.
-// Example: unsigned u = (float)INT_MAX; // u will typically overflow to 0.
-// To fix this bug we manually truncate the maximum value when the destination
-// type is an integral of larger precision than the source floating-point type,
-// such that the resulting maximum is represented exactly as a floating point.
-template <typename Dst, typename Src>
-struct NarrowingRange {
- typedef typename std::numeric_limits<Src> SrcLimits;
- typedef typename std::numeric_limits<Dst> DstLimits;
-
- static Dst max() {
- // The following logic avoids warnings where the max function is
- // instantiated with invalid values for a bit shift (even though
- // such a function can never be called).
- static const int shift =
- (MaxExponent<Src>::value > MaxExponent<Dst>::value &&
- SrcLimits::digits < DstLimits::digits && SrcLimits::is_iec559 &&
- DstLimits::is_integer)
- ? (DstLimits::digits - SrcLimits::digits)
- : 0;
-
- // We use UINTMAX_C below to avoid compiler warnings about shifting floating
- // points. Since it's a compile time calculation, it shouldn't have any
- // performance impact.
- return DstLimits::max() - static_cast<Dst>((UINTMAX_C(1) << shift) - 1);
- }
-
- static Dst min() {
- return std::numeric_limits<Dst>::is_iec559 ? -DstLimits::max()
- : DstLimits::min();
- }
-};
-
-template <
- typename Dst,
- typename Src,
- IntegerRepresentation DstSign = std::numeric_limits<Dst>::is_signed
- ? INTEGER_REPRESENTATION_SIGNED
- : INTEGER_REPRESENTATION_UNSIGNED,
- IntegerRepresentation SrcSign = std::numeric_limits<Src>::is_signed
- ? INTEGER_REPRESENTATION_SIGNED
- : INTEGER_REPRESENTATION_UNSIGNED,
- NumericRangeRepresentation DstRange =
- StaticDstRangeRelationToSrcRange<Dst, Src>::value >
-struct DstRangeRelationToSrcRangeImpl;
-
-// 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 is statically determined to contain Src: Nothing to check.
-template <typename Dst,
- typename Src,
- IntegerRepresentation DstSign,
- IntegerRepresentation SrcSign>
-struct DstRangeRelationToSrcRangeImpl<Dst,
- Src,
- DstSign,
- SrcSign,
- NUMERIC_RANGE_CONTAINED> {
- static RangeConstraint Check(Src value) { return RANGE_VALID; }
-};
-
-// Signed to signed narrowing: Both the upper and lower boundaries may be
-// exceeded.
-template <typename Dst, typename Src>
-struct DstRangeRelationToSrcRangeImpl<Dst,
- Src,
- INTEGER_REPRESENTATION_SIGNED,
- INTEGER_REPRESENTATION_SIGNED,
- NUMERIC_RANGE_NOT_CONTAINED> {
- static RangeConstraint Check(Src value) {
- return GetRangeConstraint((value <= NarrowingRange<Dst, Src>::max()),
- (value >= NarrowingRange<Dst, Src>::min()));
- }
-};
-
-// Unsigned to unsigned narrowing: Only the upper boundary can be exceeded.
-template <typename Dst, typename Src>
-struct DstRangeRelationToSrcRangeImpl<Dst,
- Src,
- INTEGER_REPRESENTATION_UNSIGNED,
- INTEGER_REPRESENTATION_UNSIGNED,
- NUMERIC_RANGE_NOT_CONTAINED> {
- static RangeConstraint Check(Src value) {
- return GetRangeConstraint(value <= NarrowingRange<Dst, Src>::max(), true);
- }
-};
-
-// Unsigned to signed: The upper boundary may be exceeded.
-template <typename Dst, typename Src>
-struct DstRangeRelationToSrcRangeImpl<Dst,
- Src,
- INTEGER_REPRESENTATION_SIGNED,
- INTEGER_REPRESENTATION_UNSIGNED,
- NUMERIC_RANGE_NOT_CONTAINED> {
- static RangeConstraint Check(Src value) {
- return sizeof(Dst) > sizeof(Src)
- ? RANGE_VALID
- : GetRangeConstraint(
- value <= static_cast<Src>(NarrowingRange<Dst, Src>::max()),
- true);
- }
-};
-
-// Signed to unsigned: The upper boundary may be exceeded for a narrower Dst,
-// and any negative value exceeds the lower boundary.
-template <typename Dst, typename Src>
-struct DstRangeRelationToSrcRangeImpl<Dst,
- Src,
- INTEGER_REPRESENTATION_UNSIGNED,
- INTEGER_REPRESENTATION_SIGNED,
- NUMERIC_RANGE_NOT_CONTAINED> {
- static RangeConstraint Check(Src value) {
- return (MaxExponent<Dst>::value >= MaxExponent<Src>::value)
- ? GetRangeConstraint(true, value >= static_cast<Src>(0))
- : GetRangeConstraint(
- value <= static_cast<Src>(NarrowingRange<Dst, Src>::max()),
- value >= static_cast<Src>(0));
- }
-};
-
-template <typename Dst, typename Src>
-inline RangeConstraint DstRangeRelationToSrcRange(Src value) {
- static_assert(std::numeric_limits<Src>::is_specialized,
- "Argument must be numeric.");
- static_assert(std::numeric_limits<Dst>::is_specialized,
- "Result must be numeric.");
- return DstRangeRelationToSrcRangeImpl<Dst, Src>::Check(value);
-}
-
-} // namespace internal
-} // namespace base
-
-#endif // BASE_NUMERICS_SAFE_CONVERSIONS_IMPL_H_