Add most of base/ build/ buildtools/ testing/ third_party/googletest/
Enough to make ./tools/gn/bootstrap/bootstrap.py work on Linux.
Change-Id: I94de95f1ce87dd3672d1a99c62254edee8be45bd
Reviewed-on: https://gn-review.googlesource.com/1100
Reviewed-by: Petr Hosek <phosek@google.com>
Commit-Queue: Scott Graham <scottmg@chromium.org>
diff --git a/base/numerics/checked_math.h b/base/numerics/checked_math.h
new file mode 100644
index 0000000..ede3344
--- /dev/null
+++ b/base/numerics/checked_math.h
@@ -0,0 +1,393 @@
+// Copyright 2017 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_CHECKED_MATH_H_
+#define BASE_NUMERICS_CHECKED_MATH_H_
+
+#include <stddef.h>
+
+#include <limits>
+#include <type_traits>
+
+#include "base/numerics/checked_math_impl.h"
+
+namespace base {
+namespace internal {
+
+template <typename T>
+class CheckedNumeric {
+ static_assert(std::is_arithmetic<T>::value,
+ "CheckedNumeric<T>: T must be a numeric type.");
+
+ public:
+ using type = T;
+
+ constexpr CheckedNumeric() = default;
+
+ // Copy constructor.
+ template <typename Src>
+ constexpr CheckedNumeric(const CheckedNumeric<Src>& rhs)
+ : state_(rhs.state_.value(), rhs.IsValid()) {}
+
+ template <typename Src>
+ friend class CheckedNumeric;
+
+ // This is not an explicit constructor because we implicitly upgrade regular
+ // numerics to CheckedNumerics to make them easier to use.
+ template <typename Src>
+ constexpr CheckedNumeric(Src value) // NOLINT(runtime/explicit)
+ : state_(value) {
+ static_assert(std::is_arithmetic<Src>::value, "Argument must be numeric.");
+ }
+
+ // This is not an explicit constructor because we want a seamless conversion
+ // from StrictNumeric types.
+ template <typename Src>
+ constexpr CheckedNumeric(
+ StrictNumeric<Src> value) // NOLINT(runtime/explicit)
+ : state_(static_cast<Src>(value)) {}
+
+ // IsValid() - The public API to test if a CheckedNumeric is currently valid.
+ // A range checked destination type can be supplied using the Dst template
+ // parameter.
+ template <typename Dst = T>
+ constexpr bool IsValid() const {
+ return state_.is_valid() &&
+ IsValueInRangeForNumericType<Dst>(state_.value());
+ }
+
+ // AssignIfValid(Dst) - Assigns the underlying value if it is currently valid
+ // and is within the range supported by the destination type. Returns true if
+ // successful and false otherwise.
+ template <typename Dst>
+#if defined(__clang__) || defined(__GNUC__)
+ __attribute__((warn_unused_result))
+#elif defined(_MSC_VER)
+ _Check_return_
+#endif
+ constexpr bool
+ AssignIfValid(Dst* result) const {
+ return BASE_NUMERICS_LIKELY(IsValid<Dst>())
+ ? ((*result = static_cast<Dst>(state_.value())), true)
+ : false;
+ }
+
+ // ValueOrDie() - The primary accessor for the underlying value. If the
+ // current state is not valid it will CHECK and crash.
+ // A range checked destination type can be supplied using the Dst template
+ // parameter, which will trigger a CHECK if the value is not in bounds for
+ // the destination.
+ // The CHECK behavior can be overridden by supplying a handler as a
+ // template parameter, for test code, etc. However, the handler cannot access
+ // the underlying value, and it is not available through other means.
+ template <typename Dst = T, class CheckHandler = CheckOnFailure>
+ constexpr StrictNumeric<Dst> ValueOrDie() const {
+ return BASE_NUMERICS_LIKELY(IsValid<Dst>())
+ ? static_cast<Dst>(state_.value())
+ : CheckHandler::template HandleFailure<Dst>();
+ }
+
+ // ValueOrDefault(T default_value) - A convenience method that returns the
+ // current value if the state is valid, and the supplied default_value for
+ // any other state.
+ // A range checked destination type can be supplied using the Dst template
+ // parameter. WARNING: This function may fail to compile or CHECK at runtime
+ // if the supplied default_value is not within range of the destination type.
+ template <typename Dst = T, typename Src>
+ constexpr StrictNumeric<Dst> ValueOrDefault(const Src default_value) const {
+ return BASE_NUMERICS_LIKELY(IsValid<Dst>())
+ ? static_cast<Dst>(state_.value())
+ : checked_cast<Dst>(default_value);
+ }
+
+ // Returns a checked numeric of the specified type, cast from the current
+ // CheckedNumeric. If the current state is invalid or the destination cannot
+ // represent the result then the returned CheckedNumeric will be invalid.
+ template <typename Dst>
+ constexpr CheckedNumeric<typename UnderlyingType<Dst>::type> Cast() const {
+ return *this;
+ }
+
+ // This friend method is available solely for providing more detailed logging
+ // in the the tests. Do not implement it in production code, because the
+ // underlying values may change at any time.
+ template <typename U>
+ friend U GetNumericValueForTest(const CheckedNumeric<U>& src);
+
+ // Prototypes for the supported arithmetic operator overloads.
+ template <typename Src>
+ constexpr CheckedNumeric& operator+=(const Src rhs);
+ template <typename Src>
+ constexpr CheckedNumeric& operator-=(const Src rhs);
+ template <typename Src>
+ constexpr CheckedNumeric& operator*=(const Src rhs);
+ template <typename Src>
+ constexpr CheckedNumeric& operator/=(const Src rhs);
+ template <typename Src>
+ constexpr CheckedNumeric& operator%=(const Src rhs);
+ template <typename Src>
+ constexpr CheckedNumeric& operator<<=(const Src rhs);
+ template <typename Src>
+ constexpr CheckedNumeric& operator>>=(const Src rhs);
+ template <typename Src>
+ constexpr CheckedNumeric& operator&=(const Src rhs);
+ template <typename Src>
+ constexpr CheckedNumeric& operator|=(const Src rhs);
+ template <typename Src>
+ constexpr CheckedNumeric& operator^=(const Src rhs);
+
+ constexpr CheckedNumeric operator-() const {
+ // The negation of two's complement int min is int min, so we simply
+ // check for that in the constexpr case.
+ // We use an optimized code path for a known run-time variable.
+ return MustTreatAsConstexpr(state_.value()) || !std::is_signed<T>::value ||
+ std::is_floating_point<T>::value
+ ? CheckedNumeric<T>(
+ NegateWrapper(state_.value()),
+ IsValid() && (!std::is_signed<T>::value ||
+ std::is_floating_point<T>::value ||
+ NegateWrapper(state_.value()) !=
+ std::numeric_limits<T>::lowest()))
+ : FastRuntimeNegate();
+ }
+
+ constexpr CheckedNumeric operator~() const {
+ return CheckedNumeric<decltype(InvertWrapper(T()))>(
+ InvertWrapper(state_.value()), IsValid());
+ }
+
+ constexpr CheckedNumeric Abs() const {
+ return !IsValueNegative(state_.value()) ? *this : -*this;
+ }
+
+ template <typename U>
+ constexpr CheckedNumeric<typename MathWrapper<CheckedMaxOp, T, U>::type> Max(
+ const U rhs) const {
+ using R = typename UnderlyingType<U>::type;
+ using result_type = typename MathWrapper<CheckedMaxOp, T, U>::type;
+ // TODO(jschuh): This can be converted to the MathOp version and remain
+ // constexpr once we have C++14 support.
+ return CheckedNumeric<result_type>(
+ static_cast<result_type>(
+ IsGreater<T, R>::Test(state_.value(), Wrapper<U>::value(rhs))
+ ? state_.value()
+ : Wrapper<U>::value(rhs)),
+ state_.is_valid() && Wrapper<U>::is_valid(rhs));
+ }
+
+ template <typename U>
+ constexpr CheckedNumeric<typename MathWrapper<CheckedMinOp, T, U>::type> Min(
+ const U rhs) const {
+ using R = typename UnderlyingType<U>::type;
+ using result_type = typename MathWrapper<CheckedMinOp, T, U>::type;
+ // TODO(jschuh): This can be converted to the MathOp version and remain
+ // constexpr once we have C++14 support.
+ return CheckedNumeric<result_type>(
+ static_cast<result_type>(
+ IsLess<T, R>::Test(state_.value(), Wrapper<U>::value(rhs))
+ ? state_.value()
+ : Wrapper<U>::value(rhs)),
+ state_.is_valid() && Wrapper<U>::is_valid(rhs));
+ }
+
+ // This function is available only for integral types. It returns an unsigned
+ // integer of the same width as the source type, containing the absolute value
+ // of the source, and properly handling signed min.
+ constexpr CheckedNumeric<typename UnsignedOrFloatForSize<T>::type>
+ UnsignedAbs() const {
+ return CheckedNumeric<typename UnsignedOrFloatForSize<T>::type>(
+ SafeUnsignedAbs(state_.value()), state_.is_valid());
+ }
+
+ constexpr CheckedNumeric& operator++() {
+ *this += 1;
+ return *this;
+ }
+
+ constexpr CheckedNumeric operator++(int) {
+ CheckedNumeric value = *this;
+ *this += 1;
+ return value;
+ }
+
+ constexpr CheckedNumeric& operator--() {
+ *this -= 1;
+ return *this;
+ }
+
+ constexpr CheckedNumeric operator--(int) {
+ CheckedNumeric value = *this;
+ *this -= 1;
+ return value;
+ }
+
+ // These perform the actual math operations on the CheckedNumerics.
+ // Binary arithmetic operations.
+ template <template <typename, typename, typename> class M,
+ typename L,
+ typename R>
+ static constexpr CheckedNumeric MathOp(const L lhs, const R rhs) {
+ using Math = typename MathWrapper<M, L, R>::math;
+ T result = 0;
+ bool is_valid =
+ Wrapper<L>::is_valid(lhs) && Wrapper<R>::is_valid(rhs) &&
+ Math::Do(Wrapper<L>::value(lhs), Wrapper<R>::value(rhs), &result);
+ return CheckedNumeric<T>(result, is_valid);
+ }
+
+ // Assignment arithmetic operations.
+ template <template <typename, typename, typename> class M, typename R>
+ constexpr CheckedNumeric& MathOp(const R rhs) {
+ using Math = typename MathWrapper<M, T, R>::math;
+ T result = 0; // Using T as the destination saves a range check.
+ bool is_valid = state_.is_valid() && Wrapper<R>::is_valid(rhs) &&
+ Math::Do(state_.value(), Wrapper<R>::value(rhs), &result);
+ *this = CheckedNumeric<T>(result, is_valid);
+ return *this;
+ }
+
+ private:
+ CheckedNumericState<T> state_;
+
+ CheckedNumeric FastRuntimeNegate() const {
+ T result;
+ bool success = CheckedSubOp<T, T>::Do(T(0), state_.value(), &result);
+ return CheckedNumeric<T>(result, IsValid() && success);
+ }
+
+ template <typename Src>
+ constexpr CheckedNumeric(Src value, bool is_valid)
+ : state_(value, is_valid) {}
+
+ // These wrappers allow us to handle state the same way for both
+ // CheckedNumeric and POD arithmetic types.
+ template <typename Src>
+ struct Wrapper {
+ static constexpr bool is_valid(Src) { return true; }
+ static constexpr Src value(Src value) { return value; }
+ };
+
+ template <typename Src>
+ struct Wrapper<CheckedNumeric<Src>> {
+ static constexpr bool is_valid(const CheckedNumeric<Src> v) {
+ return v.IsValid();
+ }
+ static constexpr Src value(const CheckedNumeric<Src> v) {
+ return v.state_.value();
+ }
+ };
+
+ template <typename Src>
+ struct Wrapper<StrictNumeric<Src>> {
+ static constexpr bool is_valid(const StrictNumeric<Src>) { return true; }
+ static constexpr Src value(const StrictNumeric<Src> v) {
+ return static_cast<Src>(v);
+ }
+ };
+};
+
+// Convenience functions to avoid the ugly template disambiguator syntax.
+template <typename Dst, typename Src>
+constexpr bool IsValidForType(const CheckedNumeric<Src> value) {
+ return value.template IsValid<Dst>();
+}
+
+template <typename Dst, typename Src>
+constexpr StrictNumeric<Dst> ValueOrDieForType(
+ const CheckedNumeric<Src> value) {
+ return value.template ValueOrDie<Dst>();
+}
+
+template <typename Dst, typename Src, typename Default>
+constexpr StrictNumeric<Dst> ValueOrDefaultForType(
+ const CheckedNumeric<Src> value,
+ const Default default_value) {
+ return value.template ValueOrDefault<Dst>(default_value);
+}
+
+// Convience wrapper to return a new CheckedNumeric from the provided arithmetic
+// or CheckedNumericType.
+template <typename T>
+constexpr CheckedNumeric<typename UnderlyingType<T>::type> MakeCheckedNum(
+ const T value) {
+ return value;
+}
+
+// These implement the variadic wrapper for the math operations.
+template <template <typename, typename, typename> class M,
+ typename L,
+ typename R>
+constexpr CheckedNumeric<typename MathWrapper<M, L, R>::type> CheckMathOp(
+ const L lhs,
+ const R rhs) {
+ using Math = typename MathWrapper<M, L, R>::math;
+ return CheckedNumeric<typename Math::result_type>::template MathOp<M>(lhs,
+ rhs);
+}
+
+// General purpose wrapper template for arithmetic operations.
+template <template <typename, typename, typename> class M,
+ typename L,
+ typename R,
+ typename... Args>
+constexpr CheckedNumeric<typename ResultType<M, L, R, Args...>::type>
+CheckMathOp(const L lhs, const R rhs, const Args... args) {
+ return CheckMathOp<M>(CheckMathOp<M>(lhs, rhs), args...);
+}
+
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, Add, +, +=)
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, Sub, -, -=)
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, Mul, *, *=)
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, Div, /, /=)
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, Mod, %, %=)
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, Lsh, <<, <<=)
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, Rsh, >>, >>=)
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, And, &, &=)
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, Or, |, |=)
+BASE_NUMERIC_ARITHMETIC_OPERATORS(Checked, Check, Xor, ^, ^=)
+BASE_NUMERIC_ARITHMETIC_VARIADIC(Checked, Check, Max)
+BASE_NUMERIC_ARITHMETIC_VARIADIC(Checked, Check, Min)
+
+// These are some extra StrictNumeric operators to support simple pointer
+// arithmetic with our result types. Since wrapping on a pointer is always
+// bad, we trigger the CHECK condition here.
+template <typename L, typename R>
+L* operator+(L* lhs, const StrictNumeric<R> rhs) {
+ uintptr_t result = CheckAdd(reinterpret_cast<uintptr_t>(lhs),
+ CheckMul(sizeof(L), static_cast<R>(rhs)))
+ .template ValueOrDie<uintptr_t>();
+ return reinterpret_cast<L*>(result);
+}
+
+template <typename L, typename R>
+L* operator-(L* lhs, const StrictNumeric<R> rhs) {
+ uintptr_t result = CheckSub(reinterpret_cast<uintptr_t>(lhs),
+ CheckMul(sizeof(L), static_cast<R>(rhs)))
+ .template ValueOrDie<uintptr_t>();
+ return reinterpret_cast<L*>(result);
+}
+
+} // namespace internal
+
+using internal::CheckedNumeric;
+using internal::IsValidForType;
+using internal::ValueOrDieForType;
+using internal::ValueOrDefaultForType;
+using internal::MakeCheckedNum;
+using internal::CheckMax;
+using internal::CheckMin;
+using internal::CheckAdd;
+using internal::CheckSub;
+using internal::CheckMul;
+using internal::CheckDiv;
+using internal::CheckMod;
+using internal::CheckLsh;
+using internal::CheckRsh;
+using internal::CheckAnd;
+using internal::CheckOr;
+using internal::CheckXor;
+
+} // namespace base
+
+#endif // BASE_NUMERICS_CHECKED_MATH_H_
