mdebray/tvl-depot
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Export of internal Abseil changes.

Browse source 
--
ed3a3431eee9e48e6553b0320e0308d2dde6725c by Derek Mauro <dmauro@google.com>:

Project import generated by Copybara.

PiperOrigin-RevId: 258631680
GitOrigin-RevId: ed3a3431eee9e48e6553b0320e0308d2dde6725c
Change-Id: I1d7ae86a79783842092d29504605ba039c369603
This commit is contained in:
Abseil Team 2019-07-17 16:35:47 -04:00 committed by Derek Mauro
parent 44efe96dfc
commit c6c3c1b498
32 changed files with 1168 additions and 657 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
absl/base/spinlock_test_common.cc
View file

@ -62,7 +62,6 @@ static SpinLock static_cooperative_spinlock(
static SpinLock static_noncooperative_spinlock(
base_internal::kLinkerInitialized, base_internal::SCHEDULE_KERNEL_ONLY);
// Simple integer hash function based on the public domain lookup2 hash.
// http://burtleburtle.net/bob/c/lookup2.c
static uint32_t Hash32(uint32_t a, uint32_t c) {
@ -194,6 +193,7 @@ TEST(SpinLock, WaitCyclesEncoding) {
TEST(SpinLockWithThreads, StaticSpinLock) {
ThreadedTest(&static_spinlock);
}
TEST(SpinLockWithThreads, StackSpinLock) {
SpinLock spinlock;
ThreadedTest(&spinlock);

3
absl/container/BUILD.bazel
View file

@ -44,7 +44,10 @@ cc_test(
linkopts = ABSL_DEFAULT_LINKOPTS,
deps = [
":compressed_tuple",
":test_instance_tracker",
"//absl/memory",
"//absl/types:any",
"//absl/types:optional",
"//absl/utility",
"@com_google_googletest//:gtest_main",
],

3
absl/container/CMakeLists.txt
View file

@ -43,8 +43,11 @@ absl_cc_test(
COPTS
${ABSL_TEST_COPTS}
DEPS
absl::any
absl::compressed_tuple
absl::memory
absl::optional
absl::test_instance_tracker
absl::utility
gmock_main
)

23
absl/container/internal/common.h
View file

@ -77,10 +77,18 @@ class node_handle_base {
protected:
friend struct CommonAccess;
node_handle_base(const allocator_type& a, slot_type* s) : alloc_(a) {
struct transfer_tag_t {};
node_handle_base(transfer_tag_t, const allocator_type& a, slot_type* s)
: alloc_(a) {
PolicyTraits::transfer(alloc(), slot(), s);
}
struct move_tag_t {};
node_handle_base(move_tag_t, const allocator_type& a, slot_type* s)
: alloc_(a) {
PolicyTraits::construct(alloc(), slot(), s);
}
void destroy() {
if (!empty()) {
PolicyTraits::destroy(alloc(), slot());
@ -121,7 +129,7 @@ class node_handle : public node_handle_base<PolicyTraits, Alloc> {
private:
friend struct CommonAccess;
node_handle(const Alloc& a, typename Base::slot_type* s) : Base(a, s) {}
using Base::Base;
};
// For maps.
@ -148,7 +156,7 @@ class node_handle<Policy, PolicyTraits, Alloc,
private:
friend struct CommonAccess;
node_handle(const Alloc& a, typename Base::slot_type* s) : Base(a, s) {}
using Base::Base;
};
// Provide access to non-public node-handle functions.
@ -164,8 +172,13 @@ struct CommonAccess {
}
template <typename T, typename... Args>
static T Make(Args&&... args) {
return T(std::forward<Args>(args)...);
static T Transfer(Args&&... args) {
return T(typename T::transfer_tag_t{}, std::forward<Args>(args)...);
}
template <typename T, typename... Args>
static T Move(Args&&... args) {
return T(typename T::move_tag_t{}, std::forward<Args>(args)...);
}
};

49
absl/container/internal/compressed_tuple.h
View file

@ -102,7 +102,9 @@ template <typename T, size_t I,
struct Storage {
T value;
constexpr Storage() = default;
explicit constexpr Storage(T&& v) : value(absl::forward<T>(v)) {}
template <typename V>
explicit constexpr Storage(absl::in_place_t, V&& v)
: value(absl::forward<V>(v)) {}
constexpr const T& get() const& { return value; }
T& get() & { return value; }
constexpr const T&& get() const&& { return absl::move(*this).value; }
@ -112,7 +114,11 @@ struct Storage {
template <typename T, size_t I>
struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC Storage<T, I, true> : T {
constexpr Storage() = default;
explicit constexpr Storage(T&& v) : T(absl::forward<T>(v)) {}
template <typename V>
explicit constexpr Storage(absl::in_place_t, V&& v)
: T(absl::forward<V>(v)) {}
constexpr const T& get() const& { return *this; }
T& get() & { return *this; }
constexpr const T&& get() const&& { return absl::move(*this); }
@ -132,8 +138,9 @@ struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTupleImpl<
: uses_inheritance,
Storage<Ts, std::integral_constant<size_t, I>::value>... {
constexpr CompressedTupleImpl() = default;
explicit constexpr CompressedTupleImpl(Ts&&... args)
: Storage<Ts, I>(absl::forward<Ts>(args))... {}
template <typename... Vs>
explicit constexpr CompressedTupleImpl(absl::in_place_t, Vs&&... args)
: Storage<Ts, I>(absl::in_place, absl::forward<Vs>(args))... {}
friend CompressedTuple<Ts...>;
};
@ -143,8 +150,9 @@ struct ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTupleImpl<
// We use the dummy identity function as above...
: Storage<Ts, std::integral_constant<size_t, I>::value, false>... {
constexpr CompressedTupleImpl() = default;
explicit constexpr CompressedTupleImpl(Ts&&... args)
: Storage<Ts, I, false>(absl::forward<Ts>(args))... {}
template <typename... Vs>
explicit constexpr CompressedTupleImpl(absl::in_place_t, Vs&&... args)
: Storage<Ts, I, false>(absl::in_place, absl::forward<Vs>(args))... {}
friend CompressedTuple<Ts...>;
};
@ -159,6 +167,11 @@ constexpr bool ShouldAnyUseBase() {
Or({std::integral_constant<bool, ShouldUseBase<Ts>()>()...})){};
}
template <typename T, typename V>
using TupleMoveConstructible = typename std::conditional<
std::is_reference<T>::value, std::is_convertible<V, T>,
std::is_constructible<T, V&&>>::type;
} // namespace internal_compressed_tuple
// Helper class to perform the Empty Base Class Optimization.
@ -192,9 +205,29 @@ class ABSL_INTERNAL_COMPRESSED_TUPLE_DECLSPEC CompressedTuple
using StorageT = internal_compressed_tuple::Storage<ElemT<I>, I>;
public:
// There seems to be a bug in MSVC dealing in which using '=default' here will
// cause the compiler to ignore the body of other constructors. The work-
// around is to explicitly implement the default constructor.
#if defined(_MSC_VER)
constexpr CompressedTuple() : CompressedTuple::CompressedTupleImpl() {}
#else
constexpr CompressedTuple() = default;
explicit constexpr CompressedTuple(Ts... base)
: CompressedTuple::CompressedTupleImpl(absl::forward<Ts>(base)...) {}
#endif
explicit constexpr CompressedTuple(const Ts&... base)
: CompressedTuple::CompressedTupleImpl(absl::in_place, base...) {}
template <typename... Vs,
absl::enable_if_t<
absl::conjunction<
// Ensure we are not hiding default copy/move constructors.
absl::negation<std::is_same<void(CompressedTuple),
void(absl::decay_t<Vs>...)>>,
internal_compressed_tuple::TupleMoveConstructible<
Ts, Vs&&>...>::value,
bool> = true>
explicit constexpr CompressedTuple(Vs&&... base)
: CompressedTuple::CompressedTupleImpl(absl::in_place,
absl::forward<Vs>(base)...) {}
template <int I>
ElemT<I>& get() & {

201
absl/container/internal/compressed_tuple_test.cc
View file

@ -19,7 +19,10 @@
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/container/internal/test_instance_tracker.h"
#include "absl/memory/memory.h"
#include "absl/types/any.h"
#include "absl/types/optional.h"
#include "absl/utility/utility.h"
// These are declared at global scope purely so that error messages
@ -43,10 +46,14 @@ struct TwoValues {
U value2;
};
namespace absl {
namespace container_internal {
namespace {
using absl::test_internal::CopyableMovableInstance;
using absl::test_internal::InstanceTracker;
TEST(CompressedTupleTest, Sizeof) {
EXPECT_EQ(sizeof(int), sizeof(CompressedTuple<int>));
EXPECT_EQ(sizeof(int), sizeof(CompressedTuple<int, Empty<0>>));
@ -62,6 +69,141 @@ TEST(CompressedTupleTest, Sizeof) {
sizeof(CompressedTuple<int, Empty<0>, NotEmpty<double>, Empty<1>>));
}
TEST(CompressedTupleTest, OneMoveOnRValueConstructionTemp) {
InstanceTracker tracker;
CompressedTuple<CopyableMovableInstance> x1(CopyableMovableInstance(1));
EXPECT_EQ(tracker.instances(), 1);
EXPECT_EQ(tracker.copies(), 0);
EXPECT_LE(tracker.moves(), 1);
EXPECT_EQ(x1.get<0>().value(), 1);
}
TEST(CompressedTupleTest, OneMoveOnRValueConstructionMove) {
InstanceTracker tracker;
CopyableMovableInstance i1(1);
CompressedTuple<CopyableMovableInstance> x1(std::move(i1));
EXPECT_EQ(tracker.instances(), 2);
EXPECT_EQ(tracker.copies(), 0);
EXPECT_LE(tracker.moves(), 1);
EXPECT_EQ(x1.get<0>().value(), 1);
}
TEST(CompressedTupleTest, OneMoveOnRValueConstructionMixedTypes) {
InstanceTracker tracker;
CopyableMovableInstance i1(1);
CopyableMovableInstance i2(2);
Empty<0> empty;
CompressedTuple<CopyableMovableInstance, CopyableMovableInstance&, Empty<0>>
x1(std::move(i1), i2, empty);
EXPECT_EQ(x1.get<0>().value(), 1);
EXPECT_EQ(x1.get<1>().value(), 2);
EXPECT_EQ(tracker.copies(), 0);
EXPECT_EQ(tracker.moves(), 1);
}
struct IncompleteType;
CompressedTuple<CopyableMovableInstance, IncompleteType&, Empty<0>>
MakeWithIncomplete(CopyableMovableInstance i1,
IncompleteType& t, // NOLINT
Empty<0> empty) {
return CompressedTuple<CopyableMovableInstance, IncompleteType&, Empty<0>>{
std::move(i1), t, empty};
}
struct IncompleteType {};
TEST(CompressedTupleTest, OneMoveOnRValueConstructionWithIncompleteType) {
InstanceTracker tracker;
CopyableMovableInstance i1(1);
Empty<0> empty;
struct DerivedType : IncompleteType {int value = 0;};
DerivedType fd;
fd.value = 7;
CompressedTuple<CopyableMovableInstance, IncompleteType&, Empty<0>> x1 =
MakeWithIncomplete(std::move(i1), fd, empty);
EXPECT_EQ(x1.get<0>().value(), 1);
EXPECT_EQ(static_cast<DerivedType&>(x1.get<1>()).value, 7);
EXPECT_EQ(tracker.copies(), 0);
EXPECT_EQ(tracker.moves(), 2);
}
TEST(CompressedTupleTest,
OneMoveOnRValueConstructionMixedTypes_BraceInitPoisonPillExpected) {
InstanceTracker tracker;
CopyableMovableInstance i1(1);
CopyableMovableInstance i2(2);
CompressedTuple<CopyableMovableInstance, CopyableMovableInstance&, Empty<0>>
x1(std::move(i1), i2, {}); // NOLINT
EXPECT_EQ(x1.get<0>().value(), 1);
EXPECT_EQ(x1.get<1>().value(), 2);
EXPECT_EQ(tracker.instances(), 3);
// We are forced into the `const Ts&...` constructor (invoking copies)
// because we need it to deduce the type of `{}`.
// std::tuple also has this behavior.
// Note, this test is proof that this is expected behavior, but it is not
// _desired_ behavior.
EXPECT_EQ(tracker.copies(), 1);
EXPECT_EQ(tracker.moves(), 0);
}
TEST(CompressedTupleTest, OneCopyOnLValueConstruction) {
InstanceTracker tracker;
CopyableMovableInstance i1(1);
CompressedTuple<CopyableMovableInstance> x1(i1);
EXPECT_EQ(tracker.copies(), 1);
EXPECT_EQ(tracker.moves(), 0);
tracker.ResetCopiesMovesSwaps();
CopyableMovableInstance i2(2);
const CopyableMovableInstance& i2_ref = i2;
CompressedTuple<CopyableMovableInstance> x2(i2_ref);
EXPECT_EQ(tracker.copies(), 1);
EXPECT_EQ(tracker.moves(), 0);
}
TEST(CompressedTupleTest, OneMoveOnRValueAccess) {
InstanceTracker tracker;
CopyableMovableInstance i1(1);
CompressedTuple<CopyableMovableInstance> x(std::move(i1));
tracker.ResetCopiesMovesSwaps();
CopyableMovableInstance i2 = std::move(x).get<0>();
EXPECT_EQ(tracker.copies(), 0);
EXPECT_EQ(tracker.moves(), 1);
}
TEST(CompressedTupleTest, OneCopyOnLValueAccess) {
InstanceTracker tracker;
CompressedTuple<CopyableMovableInstance> x(CopyableMovableInstance(0));
EXPECT_EQ(tracker.copies(), 0);
EXPECT_EQ(tracker.moves(), 1);
CopyableMovableInstance t = x.get<0>();
EXPECT_EQ(tracker.copies(), 1);
EXPECT_EQ(tracker.moves(), 1);
}
TEST(CompressedTupleTest, ZeroCopyOnRefAccess) {
InstanceTracker tracker;
CompressedTuple<CopyableMovableInstance> x(CopyableMovableInstance(0));
EXPECT_EQ(tracker.copies(), 0);
EXPECT_EQ(tracker.moves(), 1);
CopyableMovableInstance& t1 = x.get<0>();
const CopyableMovableInstance& t2 = x.get<0>();
EXPECT_EQ(tracker.copies(), 0);
EXPECT_EQ(tracker.moves(), 1);
EXPECT_EQ(t1.value(), 0);
EXPECT_EQ(t2.value(), 0);
}
TEST(CompressedTupleTest, Access) {
struct S {
std::string x;
@ -173,7 +315,40 @@ TEST(CompressedTupleTest, MoveOnlyElements) {
EXPECT_EQ(*x1, 5);
}
TEST(CompressedTupleTest, MoveConstructionMoveOnlyElements) {
CompressedTuple<std::unique_ptr<std::string>> base(
absl::make_unique<std::string>("str"));
EXPECT_EQ(*base.get<0>(), "str");
CompressedTuple<std::unique_ptr<std::string>> copy(std::move(base));
EXPECT_EQ(*copy.get<0>(), "str");
}
TEST(CompressedTupleTest, AnyElements) {
any a(std::string("str"));
CompressedTuple<any, any&> x(any(5), a);
EXPECT_EQ(absl::any_cast<int>(x.get<0>()), 5);
EXPECT_EQ(absl::any_cast<std::string>(x.get<1>()), "str");
a = 0.5f;
EXPECT_EQ(absl::any_cast<float>(x.get<1>()), 0.5);
// Ensure copy construction work in the face of a type with a universal
// implicit constructor;
CompressedTuple<absl::any> c{}, d(c); // NOLINT
}
TEST(CompressedTupleTest, Constexpr) {
struct NonTrivialStruct {
constexpr NonTrivialStruct() = default;
constexpr int value() const { return v; }
int v = 5;
};
struct TrivialStruct {
TrivialStruct() = default;
constexpr int value() const { return v; }
int v;
};
constexpr CompressedTuple<int, double, CompressedTuple<int>, Empty<0>> x(
7, 1.25, CompressedTuple<int>(5), {});
constexpr int x0 = x.get<0>();
@ -186,6 +361,32 @@ TEST(CompressedTupleTest, Constexpr) {
EXPECT_EQ(x2, 5);
EXPECT_EQ(x3, CallType::kConstRef);
#if !defined(__GNUC__) || defined(__clang__) || __GNUC__ > 4
constexpr CompressedTuple<Empty<0>, TrivialStruct, int> trivial = {};
constexpr CallType trivial0 = trivial.get<0>().value();
constexpr int trivial1 = trivial.get<1>().value();
constexpr int trivial2 = trivial.get<2>();
EXPECT_EQ(trivial0, CallType::kConstRef);
EXPECT_EQ(trivial1, 0);
EXPECT_EQ(trivial2, 0);
#endif
constexpr CompressedTuple<Empty<0>, NonTrivialStruct, absl::optional<int>>
non_trivial = {};
constexpr CallType non_trivial0 = non_trivial.get<0>().value();
constexpr int non_trivial1 = non_trivial.get<1>().value();
constexpr absl::optional<int> non_trivial2 = non_trivial.get<2>();
EXPECT_EQ(non_trivial0, CallType::kConstRef);
EXPECT_EQ(non_trivial1, 5);
EXPECT_EQ(non_trivial2, absl::nullopt);
static constexpr char data[] = "DEF";
constexpr CompressedTuple<const char*> z(data);
constexpr const char* z1 = z.get<0>();
EXPECT_EQ(std::string(z1), std::string(data));
#if defined(__clang__)
// An apparent bug in earlier versions of gcc claims these are ambiguous.
constexpr int x2m = absl::move(x.get<2>()).get<0>();

2
absl/container/internal/raw_hash_set.h
View file

@ -1182,7 +1182,7 @@ class raw_hash_set {
node_type extract(const_iterator position) {
auto node =
CommonAccess::Make<node_type>(alloc_ref(), position.inner_.slot_);
CommonAccess::Transfer<node_type>(alloc_ref(), position.inner_.slot_);
erase_meta_only(position);
return node;
}

2
absl/container/internal/test_instance_tracker.h
View file

@ -23,7 +23,7 @@
namespace absl {
namespace test_internal {
// A type that counts number of occurences of the type, the live occurrences of
// A type that counts number of occurrences of the type, the live occurrences of
// the type, as well as the number of copies, moves, swaps, and comparisons that
// have occurred on the type. This is used as a base class for the copyable,
// copyable+movable, and movable types below that are used in actual tests. Use

23
absl/flags/BUILD.bazel
View file

@ -155,14 +155,12 @@ cc_library(
)
cc_library(
name = "usage",
name = "usage_internal",
srcs = [
"internal/usage.cc",
"usage.cc",
],
hdrs = [
"internal/usage.h",
"usage.h",
],
copts = ABSL_DEFAULT_COPTS,
linkopts = ABSL_DEFAULT_LINKOPTS,
@ -179,6 +177,23 @@ cc_library(
],
)
cc_library(
name = "usage",
srcs = [
"usage.cc",
],
hdrs = [
"usage.h",
],
copts = ABSL_DEFAULT_COPTS,
linkopts = ABSL_DEFAULT_LINKOPTS,
deps = [
":usage_internal",
"//absl/strings",
"//absl/synchronization",
],
)
cc_library(
name = "parse",
srcs = ["parse.cc"],
@ -195,6 +210,7 @@ cc_library(
":internal",
":registry",
":usage",
":usage_internal",
"//absl/strings",
"//absl/synchronization",
],
@ -360,6 +376,7 @@ cc_test(
":internal",
":parse",
":usage",
":usage_internal",
"//absl/memory",
"//absl/strings",
"@com_google_googletest//:gtest",

21
absl/flags/CMakeLists.txt
View file

@ -141,13 +141,11 @@ absl_cc_library(
# Internal-only target, do not depend on directly.
absl_cc_library(
NAME
flags_usage
flags_usage_internal
SRCS
"internal/usage.cc"
"usage.cc"
HDRS
"internal/usage.h"
"usage.h"
COPTS
${ABSL_DEFAULT_COPTS}
LINKOPTS
@ -161,6 +159,23 @@ absl_cc_library(
absl::synchronization
)
absl_cc_library(
NAME
flags_usage
SRCS
"usage.cc"
HDRS
"usage.h"
COPTS
${ABSL_DEFAULT_COPTS}
LINKOPTS
${ABSL_DEFAULT_LINKOPTS}
DEPS
absl::flags_usage_internal
absl::strings
absl::synchronization
)
absl_cc_library(
NAME
flags_parse

16
absl/flags/flag.cc
View file

@ -25,23 +25,15 @@ namespace absl {
// validates the type.
#ifndef NDEBUG
#define ABSL_FLAGS_ATOMIC_GET(T) \
T GetFlag(const absl::Flag<T>& flag) { \
T result; \
flag.internal.Read(&result, &flags_internal::FlagOps<T>); \
return result; \
}
T GetFlag(const absl::Flag<T>& flag) { return flag.Get(); }
#else
#define ABSL_FLAGS_ATOMIC_GET(T) \
T GetFlag(const absl::Flag<T>& flag) { \
const int64_t r = flag.internal.atomic.load(std::memory_order_acquire); \
if (r != flags_internal::CommandLineFlag::kAtomicInit) { \
T t; \
memcpy(&t, &r, sizeof(T)); \
return t; \
} \
T result; \
flag.internal.Read(&result, &flags_internal::FlagOps<T>); \
if (flag.AtomicGet(&result)) { \
return result; \
} \
return flag.Get(); \
}
#endif

29
absl/flags/flag.h
View file

@ -91,30 +91,7 @@ T GetFlag(const absl::Flag<T>& flag) {
ABSL_FLAGS_INTERNAL_FOR_EACH_LOCK_FREE(ABSL_FLAGS_INTERNAL_LOCK_FREE_VALIDATE)
#undef ABSL_FLAGS_INTERNAL_LOCK_FREE_VALIDATE
// Implementation notes:
//
// We are wrapping a union around the value of `T` to serve three purposes:
//
// 1. `U.value` has correct size and alignment for a value of type `T`
// 2. The `U.value` constructor is not invoked since U's constructor does not
// do it explicitly.
// 3. The `U.value` destructor is invoked since U's destructor does it
// explicitly. This makes `U` a kind of RAII wrapper around non default
// constructible value of T, which is destructed when we leave the scope.
// We do need to destroy U.value, which is constructed by
// CommandLineFlag::Read even though we left it in a moved-from state
// after std::move.
//
// All of this serves to avoid requiring `T` being default constructible.
union U {
T value;
U() {}
~U() { value.~T(); }
};
U u;
flag.internal.Read(&u.value, &flags_internal::FlagOps<T>);
return std::move(u.value);
return flag.Get();
}
// Overload for `GetFlag()` for types that support lock-free reads.
@ -132,7 +109,7 @@ ABSL_FLAGS_INTERNAL_FOR_EACH_LOCK_FREE(ABSL_FLAGS_INTERNAL_LOCK_FREE_EXPORT)
// but especially within performance-critical code.
template <typename T>
void SetFlag(absl::Flag<T>* flag, const T& v) {
flag->internal.Write(&v, &flags_internal::FlagOps<T>);
flag->Set(v);
}
// Overload of `SetFlag()` to allow callers to pass in a value that is
@ -141,7 +118,7 @@ void SetFlag(absl::Flag<T>* flag, const T& v) {
template <typename T, typename V>
void SetFlag(absl::Flag<T>* flag, const V& v) {
T value(v);
SetFlag<T>(flag, value);
flag->Set(value);
}
} // namespace absl

449
absl/flags/internal/commandlineflag.cc
View file

@ -37,44 +37,6 @@ const char kStrippedFlagHelp[] = "\001\002\003\004 (unknown) \004\003\002\001";
namespace {
void StoreAtomic(CommandLineFlag* flag, const void* data, size_t size) {
int64_t t = 0;
assert(size <= sizeof(int64_t));
memcpy(&t, data, size);
flag->atomic.store(t, std::memory_order_release);
}
// If the flag has a mutation callback this function invokes it. While the
// callback is being invoked the primary flag's mutex is unlocked and it is
// re-locked back after call to callback is completed. Callback invocation is
// guarded by flag's secondary mutex instead which prevents concurrent callback
// invocation. Note that it is possible for other thread to grab the primary
// lock and update flag's value at any time during the callback invocation.
// This is by design. Callback can get a value of the flag if necessary, but it
// might be different from the value initiated the callback and it also can be
// different by the time the callback invocation is completed.
// Requires that *primary_lock be held in exclusive mode; it may be released
// and reacquired by the implementation.
void InvokeCallback(CommandLineFlag* flag, absl::Mutex* primary_lock)
EXCLUSIVE_LOCKS_REQUIRED(primary_lock) {
if (!flag->callback) return;
// The callback lock is guaranteed initialized, because *primary_lock exists.
absl::Mutex* callback_mu = &flag->locks->callback_mu;
// When executing the callback we need the primary flag's mutex to be unlocked
// so that callback can retrieve the flag's value.
primary_lock->Unlock();
{
absl::MutexLock lock(callback_mu);
flag->callback();
}
primary_lock->Lock();
}
// Currently we only validate flag values for user-defined flag types.
bool ShouldValidateFlagValue(const CommandLineFlag& flag) {
#define DONT_VALIDATE(T) \
@ -89,145 +51,72 @@ bool ShouldValidateFlagValue(const CommandLineFlag& flag) {
} // namespace
// Update any copy of the flag value that is stored in an atomic word.
// In addition if flag has a mutation callback this function invokes it.
void UpdateCopy(CommandLineFlag* flag, absl::Mutex* primary_lock)
EXCLUSIVE_LOCKS_REQUIRED(primary_lock) {
#define STORE_ATOMIC(T) \
else if (flag->IsOfType<T>()) { \
StoreAtomic(flag, flag->cur, sizeof(T)); \
absl::Mutex* InitFlag(CommandLineFlag* flag) {
ABSL_CONST_INIT static absl::Mutex init_lock(absl::kConstInit);
absl::Mutex* mu;
{
absl::MutexLock lock(&init_lock);
if (flag->locks == nullptr) { // Must initialize Mutexes for this flag.
flag->locks = new flags_internal::CommandLineFlagLocks;
}
if (false) {
mu = &flag->locks->primary_mu;
}
ABSL_FLAGS_INTERNAL_FOR_EACH_LOCK_FREE(STORE_ATOMIC)
#undef STORE_ATOMIC
InvokeCallback(flag, primary_lock);
{
absl::MutexLock lock(mu);
if (!flag->retired && flag->def == nullptr) {
// Need to initialize def and cur fields.
flag->def = (*flag->make_init_value)();
flag->cur = Clone(flag->op, flag->def);
UpdateCopy(flag);
flag->inited.store(true, std::memory_order_release);
flag->InvokeCallback();
}
}
flag->inited.store(true, std::memory_order_release);
return mu;
}
// Ensure that the lazily initialized fields of *flag have been initialized,
// and return &flag->locks->primary_mu.
absl::Mutex* InitFlagIfNecessary(CommandLineFlag* flag)
LOCK_RETURNED(flag->locks->primary_mu) {
absl::Mutex* mu;
if (!flag->inited.load(std::memory_order_acquire)) {
// Need to initialize lazily initialized fields.
ABSL_CONST_INIT static absl::Mutex init_lock(absl::kConstInit);
init_lock.Lock();
if (flag->locks == nullptr) { // Must initialize Mutexes for this flag.
flag->locks = new flags_internal::CommandLineFlagLocks;
}
mu = &flag->locks->primary_mu;
init_lock.Unlock();
mu->Lock();
if (!flag->retired &&
flag->def == nullptr) { // Need to initialize def and cur fields.
flag->def = (*flag->make_init_value)();
flag->cur = Clone(flag->op, flag->def);
UpdateCopy(flag, mu);
}
mu->Unlock();
flag->inited.store(true, std::memory_order_release);
} else { // All fields initialized; flag->locks is therefore safe to read.
mu = &flag->locks->primary_mu;
}
return mu;
absl::Mutex* CommandLineFlag::InitFlagIfNecessary() const
LOCK_RETURNED(locks->primary_mu) {
if (!this->inited.load(std::memory_order_acquire)) {
return InitFlag(const_cast<CommandLineFlag*>(this));
}
// Return true iff flag value was changed via direct-access.
bool ChangedDirectly(CommandLineFlag* flag, const void* a, const void* b) {
if (!flag->IsAbseilFlag()) {
// Need to compare values for direct-access flags.
#define CHANGED_FOR_TYPE(T) \
if (flag->IsOfType<T>()) { \
return *reinterpret_cast<const T*>(a) != *reinterpret_cast<const T*>(b); \
// All fields initialized; this->locks is therefore safe to read.
return &this->locks->primary_mu;
}
CHANGED_FOR_TYPE(bool);
CHANGED_FOR_TYPE(int32_t);
CHANGED_FOR_TYPE(int64_t);
CHANGED_FOR_TYPE(uint64_t);
CHANGED_FOR_TYPE(double);
CHANGED_FOR_TYPE(std::string);
#undef CHANGED_FOR_TYPE
}
return false;
void CommandLineFlag::Destroy() const {
// Values are heap allocated for retired and Abseil Flags.
if (IsRetired() || IsAbseilFlag()) {
if (this->cur) Delete(this->op, this->cur);
if (this->def) Delete(this->op, this->def);
}
// Direct-access flags can be modified without going through the
// flag API. Detect such changes and updated the modified bit.
void UpdateModifiedBit(CommandLineFlag* flag) {
if (!flag->IsAbseilFlag()) {
absl::MutexLock l(InitFlagIfNecessary(flag));
if (!flag->modified && ChangedDirectly(flag, flag->cur, flag->def)) {
flag->modified = true;
}
}
delete this->locks;
}
bool Validate(CommandLineFlag*, const void*) {
return true;
bool CommandLineFlag::IsModified() const {
absl::MutexLock l(InitFlagIfNecessary());
return modified;
}
std::string HelpText::GetHelpText() const {
if (help_function_) return help_function_();
if (help_message_) return help_message_;
return {};
void CommandLineFlag::SetModified(bool is_modified) {
absl::MutexLock l(InitFlagIfNecessary());
modified = is_modified;
}
const int64_t CommandLineFlag::kAtomicInit;
void CommandLineFlag::Read(void* dst,
const flags_internal::FlagOpFn dst_op) const {
absl::ReaderMutexLock l(
InitFlagIfNecessary(const_cast<CommandLineFlag*>(this)));
// `dst_op` is the unmarshaling operation corresponding to the declaration
// visibile at the call site. `op` is the Flag's defined unmarshalling
// operation. They must match for this operation to be well-defined.
if (ABSL_PREDICT_FALSE(dst_op != op)) {
ABSL_INTERNAL_LOG(
ERROR,
absl::StrCat("Flag '", name,
"' is defined as one type and declared as another"));
}
CopyConstruct(op, cur, dst);
}
void CommandLineFlag::Write(const void* src,
const flags_internal::FlagOpFn src_op) {
absl::Mutex* mu = InitFlagIfNecessary(this);
absl::MutexLock l(mu);
// `src_op` is the marshalling operation corresponding to the declaration
// visible at the call site. `op` is the Flag's defined marshalling operation.
// They must match for this operation to be well-defined.
if (ABSL_PREDICT_FALSE(src_op != op)) {
ABSL_INTERNAL_LOG(
ERROR,
absl::StrCat("Flag '", name,
"' is defined as one type and declared as another"));
}
if (ShouldValidateFlagValue(*this)) {
void* obj = Clone(op, src);
std::string ignored_error;
std::string src_as_str = Unparse(marshalling_op, src);
if (!Parse(marshalling_op, src_as_str, obj, &ignored_error) ||
!Validate(this, obj)) {
ABSL_INTERNAL_LOG(ERROR, absl::StrCat("Attempt to set flag '", name,
"' to invalid value ", src_as_str));
}
Delete(op, obj);
}
modified = true;
counter++;
Copy(op, src, cur);
UpdateCopy(this, mu);
bool CommandLineFlag::IsSpecifiedOnCommandLine() const {
absl::MutexLock l(InitFlagIfNecessary());
return on_command_line;
}
absl::string_view CommandLineFlag::Typename() const {
@ -259,21 +148,96 @@ std::string CommandLineFlag::Filename() const {
}
std::string CommandLineFlag::DefaultValue() const {
absl::MutexLock l(InitFlagIfNecessary());
return Unparse(this->marshalling_op, this->def);
}
std::string CommandLineFlag::CurrentValue() const {
absl::MutexLock l(InitFlagIfNecessary());
return Unparse(this->marshalling_op, this->cur);
}
bool CommandLineFlag::HasValidatorFn() const {
absl::MutexLock l(InitFlagIfNecessary());
return this->validator != nullptr;
}
bool CommandLineFlag::SetValidatorFn(FlagValidator fn) {
absl::MutexLock l(InitFlagIfNecessary());
// ok to register the same function over and over again
if (fn == this->validator) return true;
// Can't set validator to a different function, unless reset first.
if (fn != nullptr && this->validator != nullptr) {
ABSL_INTERNAL_LOG(
WARNING, absl::StrCat("Ignoring SetValidatorFn() for flag '", Name(),
"': validate-fn already registered"));
return false;
}
this->validator = fn;
return true;
}
bool CommandLineFlag::InvokeValidator(const void* value) const
EXCLUSIVE_LOCKS_REQUIRED(this->locks->primary_mu) {
if (!this->validator) {
return true;
}
(void)value;
ABSL_INTERNAL_LOG(
FATAL,
absl::StrCat("Flag '", Name(),
"' of encapsulated type should not have a validator"));
return false;
}
void CommandLineFlag::SetCallback(
const flags_internal::FlagCallback mutation_callback) {
absl::Mutex* mu = InitFlagIfNecessary(this);
absl::MutexLock l(mu);
absl::MutexLock l(InitFlagIfNecessary());
callback = mutation_callback;
InvokeCallback(this, mu);
InvokeCallback();
}
// If the flag has a mutation callback this function invokes it. While the
// callback is being invoked the primary flag's mutex is unlocked and it is
// re-locked back after call to callback is completed. Callback invocation is
// guarded by flag's secondary mutex instead which prevents concurrent callback
// invocation. Note that it is possible for other thread to grab the primary
// lock and update flag's value at any time during the callback invocation.
// This is by design. Callback can get a value of the flag if necessary, but it
// might be different from the value initiated the callback and it also can be
// different by the time the callback invocation is completed.
// Requires that *primary_lock be held in exclusive mode; it may be released
// and reacquired by the implementation.
void CommandLineFlag::InvokeCallback()
EXCLUSIVE_LOCKS_REQUIRED(this->locks->primary_mu) {
if (!this->callback) return;
// The callback lock is guaranteed initialized, because *locks->primary_mu
// exists.
absl::Mutex* callback_mu = &this->locks->callback_mu;
// When executing the callback we need the primary flag's mutex to be unlocked
// so that callback can retrieve the flag's value.
this->locks->primary_mu.Unlock();
{
absl::MutexLock lock(callback_mu);
this->callback();
}
this->locks->primary_mu.Lock();
}
// Attempts to parse supplied `value` string using parsing routine in the `flag`
@ -282,8 +246,9 @@ void CommandLineFlag::SetCallback(
// parsed value in 'dst' assuming it is a pointer to the flag's value type. In
// case if any error is encountered in either step, the error message is stored
// in 'err'
static bool TryParseLocked(CommandLineFlag* flag, void* dst,
absl::string_view value, std::string* err) {
bool TryParseLocked(CommandLineFlag* flag, void* dst, absl::string_view value,
std::string* err)
EXCLUSIVE_LOCKS_REQUIRED(flag->locks->primary_mu) {
void* tentative_value = Clone(flag->op, flag->def);
std::string parse_err;
if (!Parse(flag->marshalling_op, value, tentative_value, &parse_err)) {
@ -297,7 +262,7 @@ static bool TryParseLocked(CommandLineFlag* flag, void* dst,
return false;
}
if (!Validate(flag, tentative_value)) {
if (!flag->InvokeValidator(tentative_value)) {
*err = absl::StrCat("Failed validation of new value '",
Unparse(flag->marshalling_op, tentative_value),
"' for flag '", flag->Name(), "'");
@ -324,17 +289,23 @@ bool CommandLineFlag::SetFromString(absl::string_view value,
ValueSource source, std::string* err) {
if (IsRetired()) return false;
UpdateModifiedBit(this);
absl::MutexLock l(InitFlagIfNecessary());
absl::Mutex* mu = InitFlagIfNecessary(this);
absl::MutexLock l(mu);
// Direct-access flags can be modified without going through the
// flag API. Detect such changes and update the flag->modified bit.
if (!IsAbseilFlag()) {
if (!this->modified && ChangedDirectly(this, this->cur, this->def)) {
this->modified = true;
}
}
switch (set_mode) {
case SET_FLAGS_VALUE: {
// set or modify the flag's value
if (!TryParseLocked(this, this->cur, value, err)) return false;
this->modified = true;
UpdateCopy(this, mu);
UpdateCopy(this);
InvokeCallback();
if (source == kCommandLine) {
this->on_command_line = true;
@ -346,7 +317,8 @@ bool CommandLineFlag::SetFromString(absl::string_view value,
if (!this->modified) {
if (!TryParseLocked(this, this->cur, value, err)) return false;
this->modified = true;
UpdateCopy(this, mu);
UpdateCopy(this);
InvokeCallback();
} else {
// TODO(rogeeff): review and fix this semantic. Currently we do not fail
// in this case if flag is modified. This is misleading since the flag's
@ -365,7 +337,8 @@ bool CommandLineFlag::SetFromString(absl::string_view value,
if (!this->modified) {
// Need to set both defvalue *and* current, in this case
Copy(this->op, this->def, this->cur);
UpdateCopy(this, mu);
UpdateCopy(this);
InvokeCallback();
}
break;
}
@ -379,5 +352,143 @@ bool CommandLineFlag::SetFromString(absl::string_view value,
return true;
}
void CommandLineFlag::StoreAtomic(size_t size) {
int64_t t = 0;
assert(size <= sizeof(int64_t));
memcpy(&t, this->cur, size);
this->atomic.store(t, std::memory_order_release);
}
void CommandLineFlag::CheckDefaultValueParsingRoundtrip() const {
std::string v = DefaultValue();
absl::MutexLock lock(InitFlagIfNecessary());
void* dst = Clone(this->op, this->def);
std::string error;
if (!flags_internal::Parse(this->marshalling_op, v, dst, &error)) {
ABSL_INTERNAL_LOG(
FATAL,
absl::StrCat("Flag ", Name(), " (from ", Filename(),
"): std::string form of default value '", v,
"' could not be parsed; error=", error));
}
// We do not compare dst to def since parsing/unparsing may make
// small changes, e.g., precision loss for floating point types.
Delete(this->op, dst);
}
bool CommandLineFlag::ValidateDefaultValue() const {
absl::MutexLock lock(InitFlagIfNecessary());
return InvokeValidator(this->def);
}
bool CommandLineFlag::ValidateInputValue(absl::string_view value) const {
absl::MutexLock l(InitFlagIfNecessary()); // protect default value access
void* obj = Clone(this->op, this->def);
std::string ignored_error;
const bool result =
flags_internal::Parse(this->marshalling_op, value, obj, &ignored_error) &&
InvokeValidator(obj);
Delete(this->op, obj);
return result;
}
const int64_t CommandLineFlag::kAtomicInit;
void CommandLineFlag::Read(void* dst,
const flags_internal::FlagOpFn dst_op) const {
absl::ReaderMutexLock l(InitFlagIfNecessary());
// `dst_op` is the unmarshaling operation corresponding to the declaration
// visibile at the call site. `op` is the Flag's defined unmarshalling
// operation. They must match for this operation to be well-defined.
if (ABSL_PREDICT_FALSE(dst_op != op)) {
ABSL_INTERNAL_LOG(
ERROR,
absl::StrCat("Flag '", name,
"' is defined as one type and declared as another"));
}
CopyConstruct(op, cur, dst);
}
void CommandLineFlag::Write(const void* src,
const flags_internal::FlagOpFn src_op) {
absl::MutexLock l(InitFlagIfNecessary());
// `src_op` is the marshalling operation corresponding to the declaration
// visible at the call site. `op` is the Flag's defined marshalling operation.
// They must match for this operation to be well-defined.
if (ABSL_PREDICT_FALSE(src_op != op)) {
ABSL_INTERNAL_LOG(
ERROR,
absl::StrCat("Flag '", name,
"' is defined as one type and declared as another"));
}
if (ShouldValidateFlagValue(*this)) {
void* obj = Clone(op, src);
std::string ignored_error;
std::string src_as_str = Unparse(marshalling_op, src);
if (!Parse(marshalling_op, src_as_str, obj, &ignored_error) ||
!InvokeValidator(obj)) {
ABSL_INTERNAL_LOG(ERROR, absl::StrCat("Attempt to set flag '", name,
"' to invalid value ", src_as_str));
}
Delete(op, obj);
}
modified = true;
counter++;
Copy(op, src, cur);
UpdateCopy(this);
InvokeCallback();
}
std::string HelpText::GetHelpText() const {
if (help_function_) return help_function_();
if (help_message_) return help_message_;
return {};
}
// Update any copy of the flag value that is stored in an atomic word.
// In addition if flag has a mutation callback this function invokes it.
void UpdateCopy(CommandLineFlag* flag) {
#define STORE_ATOMIC(T) \
else if (flag->IsOfType<T>()) { \
flag->StoreAtomic(sizeof(T)); \
}
if (false) {
}
ABSL_FLAGS_INTERNAL_FOR_EACH_LOCK_FREE(STORE_ATOMIC)
#undef STORE_ATOMIC
}
// Return true iff flag value was changed via direct-access.
bool ChangedDirectly(CommandLineFlag* flag, const void* a, const void* b) {
if (!flag->IsAbseilFlag()) {
// Need to compare values for direct-access flags.
#define CHANGED_FOR_TYPE(T) \
if (flag->IsOfType<T>()) { \
return *reinterpret_cast<const T*>(a) != *reinterpret_cast<const T*>(b); \
}
CHANGED_FOR_TYPE(bool);
CHANGED_FOR_TYPE(int32_t);
CHANGED_FOR_TYPE(int64_t);
CHANGED_FOR_TYPE(uint64_t);
CHANGED_FOR_TYPE(double);
CHANGED_FOR_TYPE(std::string);
#undef CHANGED_FOR_TYPE
}
return false;
}
} // namespace flags_internal
} // namespace absl

58
absl/flags/internal/commandlineflag.h
View file

@ -69,11 +69,15 @@ using HelpGenFunc = std::string (*)();
// based on default value supplied in flag's definition)
using InitialValGenFunc = void* (*)();
struct CommandLineFlagInfo;
// Signature for the mutation callback used by watched Flags
// The callback is noexcept.
// TODO(rogeeff): add noexcept after C++17 support is added.
using FlagCallback = void (*)();
using FlagValidator = bool (*)();
extern const char kStrippedFlagHelp[];
// The per-type function
@ -217,6 +221,9 @@ struct CommandLineFlag {
atomic(kAtomicInit),
locks(nullptr) {}
// Revert the init routine.
void Destroy() const;
// Not copyable/assignable.
CommandLineFlag(const CommandLineFlag&) = delete;
CommandLineFlag& operator=(const CommandLineFlag&) = delete;
@ -224,7 +231,9 @@ struct CommandLineFlag {
absl::string_view Name() const { return name; }
std::string Help() const { return help.GetHelpText(); }
bool IsRetired() const { return this->retired; }
bool IsSpecifiedOnCommandLine() const { return on_command_line; }
bool IsModified() const;
void SetModified(bool is_modified);
bool IsSpecifiedOnCommandLine() const;
// Returns true iff this is a handle to an Abseil Flag.
bool IsAbseilFlag() const {
// Set to null for V1 flags
@ -236,6 +245,10 @@ struct CommandLineFlag {
std::string DefaultValue() const;
std::string CurrentValue() const;
bool HasValidatorFn() const;
bool SetValidatorFn(FlagValidator fn);
bool InvokeValidator(const void* value) const;
// Return true iff flag has type T.
template <typename T>
inline bool IsOfType() const {
@ -245,7 +258,7 @@ struct CommandLineFlag {
// Attempts to retrieve the flag value. Returns value on success,
// absl::nullopt otherwise.
template <typename T>
absl::optional<T> Get() {
absl::optional<T> Get() const {
if (IsRetired() || flags_internal::FlagOps<T> != this->op)
return absl::nullopt;
@ -256,6 +269,7 @@ struct CommandLineFlag {
}
void SetCallback(const flags_internal::FlagCallback mutation_callback);
void InvokeCallback();
// Sets the value of the flag based on specified std::string `value`. If the flag
// was successfully set to new value, it returns true. Otherwise, sets `error`
@ -269,13 +283,21 @@ struct CommandLineFlag {
flags_internal::FlagSettingMode set_mode,
flags_internal::ValueSource source, std::string* error);
void StoreAtomic(size_t size);
void CheckDefaultValueParsingRoundtrip() const;
// Invoke the flag validators for old flags.
// TODO(rogeeff): implement proper validators for Abseil Flags
bool ValidateDefaultValue() const;
bool ValidateInputValue(absl::string_view value) const;
// Constant configuration for a particular flag.
private:
const char* const name;
const HelpText help;
const char* const filename;
public:
protected:
const FlagOpFn op; // Type-specific handler
const FlagMarshallingOpFn marshalling_op; // Marshalling ops handler
const InitialValGenFunc make_init_value; // Makes initial value for the flag
@ -285,7 +307,7 @@ struct CommandLineFlag {
// Mutable state (guarded by locks->primary_mu).
bool modified; // Has flag value been modified?
bool on_command_line; // Specified on command line.
bool (*validator)(); // Validator function, or nullptr
FlagValidator validator; // Validator function, or nullptr
FlagCallback callback; // Mutation callback, or nullptr
void* def; // Lazily initialized pointer to default value
void* cur; // Lazily initialized pointer to current value
@ -302,24 +324,26 @@ struct CommandLineFlag {
// TODO(rogeeff): fix it once Mutex has constexpr constructor
struct CommandLineFlagLocks* locks; // locks, laziliy allocated.
// Ensure that the lazily initialized fields of *flag have been initialized,
// and return the lock which should be locked when flag's state is mutated.
absl::Mutex* InitFlagIfNecessary() const;
// copy construct new value of flag's type in a memory referenced by dst
// based on current flag's value
void Read(void* dst, const flags_internal::FlagOpFn dst_op) const;
// updates flag's value to *src (locked)
void Write(const void* src, const flags_internal::FlagOpFn src_op);
ABSL_DEPRECATED(
"temporary until FlagName call sites are migrated and validator API is "
"changed")
const char* NameAsCString() const { return name; }
private:
friend class FlagRegistry;
friend class FlagPtrMap;
friend class FlagSaverImpl;
friend void FillCommandLineFlagInfo(CommandLineFlag* flag,
CommandLineFlagInfo* result);
friend bool TryParseLocked(CommandLineFlag* flag, void* dst,
absl::string_view value, std::string* err);
friend absl::Mutex* InitFlag(CommandLineFlag* flag);
};
// Ensure that the lazily initialized fields of *flag have been initialized,
// and return &flag->locks->primary_mu.
absl::Mutex* InitFlagIfNecessary(CommandLineFlag* flag);
// Update any copy of the flag value that is stored in an atomic word.
// In addition if flag has a mutation callback this function invokes it. While
// callback is being invoked the primary flag's mutex is unlocked and it is
@ -332,15 +356,9 @@ absl::Mutex* InitFlagIfNecessary(CommandLineFlag* flag);
// different by the time the callback invocation is completed.
// Requires that *primary_lock be held in exclusive mode; it may be released
// and reacquired by the implementation.
void UpdateCopy(CommandLineFlag* flag, absl::Mutex* primary_lock);
void UpdateCopy(CommandLineFlag* flag);
// Return true iff flag value was changed via direct-access.
bool ChangedDirectly(CommandLineFlag* flag, const void* a, const void* b);
// Direct-access flags can be modified without going through the
// flag API. Detect such changes and updated the modified bit.
void UpdateModifiedBit(CommandLineFlag* flag);
// Invoke the flag validators for old flags.
// TODO(rogeeff): implement proper validators for Abseil Flags
bool Validate(CommandLineFlag* flag, const void* value);
// This macro is the "source of truth" for the list of supported flag types we
// expect to perform lock free operations on. Specifically it generates code,

14
absl/flags/internal/commandlineflag_test.cc
View file

@ -100,39 +100,39 @@ TEST_F(CommandLineFlagTest, TestSetFromStringCurrentValue) {
std::string err;
auto* flag_01 = flags::FindCommandLineFlag("int_flag");
EXPECT_FALSE(flag_01->on_command_line);
EXPECT_FALSE(flag_01->IsSpecifiedOnCommandLine());
EXPECT_TRUE(flag_01->SetFromString("11", flags::SET_FLAGS_VALUE,
flags::kProgrammaticChange, &err));
EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), 11);
EXPECT_FALSE(flag_01->on_command_line);
EXPECT_FALSE(flag_01->IsSpecifiedOnCommandLine());
EXPECT_TRUE(flag_01->SetFromString("-123", flags::SET_FLAGS_VALUE,
flags::kProgrammaticChange, &err));
EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), -123);
EXPECT_FALSE(flag_01->on_command_line);
EXPECT_FALSE(flag_01->IsSpecifiedOnCommandLine());
EXPECT_TRUE(!flag_01->SetFromString("xyz", flags::SET_FLAGS_VALUE,
flags::kProgrammaticChange, &err));
EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), -123);
EXPECT_EQ(err, "Illegal value 'xyz' specified for flag 'int_flag'");
EXPECT_FALSE(flag_01->on_command_line);
EXPECT_FALSE(flag_01->IsSpecifiedOnCommandLine());
EXPECT_TRUE(!flag_01->SetFromString("A1", flags::SET_FLAGS_VALUE,
flags::kProgrammaticChange, &err));
EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), -123);
EXPECT_EQ(err, "Illegal value 'A1' specified for flag 'int_flag'");
EXPECT_FALSE(flag_01->on_command_line);
EXPECT_FALSE(flag_01->IsSpecifiedOnCommandLine());
EXPECT_TRUE(flag_01->SetFromString("0x10", flags::SET_FLAGS_VALUE,
flags::kProgrammaticChange, &err));
EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), 16);
EXPECT_FALSE(flag_01->on_command_line);
EXPECT_FALSE(flag_01->IsSpecifiedOnCommandLine());
EXPECT_TRUE(flag_01->SetFromString("011", flags::SET_FLAGS_VALUE,
flags::kCommandLine, &err));
EXPECT_EQ(absl::GetFlag(FLAGS_int_flag), 11);
EXPECT_TRUE(flag_01->on_command_line);
EXPECT_TRUE(flag_01->IsSpecifiedOnCommandLine());
EXPECT_TRUE(!flag_01->SetFromString("", flags::SET_FLAGS_VALUE,
flags::kProgrammaticChange, &err));

66
absl/flags/internal/flag.h
View file

@ -24,40 +24,58 @@ namespace flags_internal {
// This is "unspecified" implementation of absl::Flag<T> type.
template <typename T>
class Flag {
class Flag : public flags_internal::CommandLineFlag {
public:
constexpr Flag(const char* name, const flags_internal::HelpGenFunc help_gen,
const char* filename,
const flags_internal::FlagMarshallingOpFn marshalling_op,
const flags_internal::FlagMarshallingOpFn marshalling_op_arg,
const flags_internal::InitialValGenFunc initial_value_gen)
: internal(name, flags_internal::HelpText::FromFunctionPointer(help_gen),
filename, &flags_internal::FlagOps<T>, marshalling_op,
: flags_internal::CommandLineFlag(
name, flags_internal::HelpText::FromFunctionPointer(help_gen),
filename, &flags_internal::FlagOps<T>, marshalling_op_arg,
initial_value_gen,
/*retired_arg=*/false, /*def_arg=*/nullptr,
/*cur_arg=*/nullptr) {}
// Not copyable/assignable.
Flag(const Flag<T>&) = delete;
Flag<T>& operator=(const Flag<T>&) = delete;
T Get() const {
// Implementation notes:
//
// We are wrapping a union around the value of `T` to serve three purposes:
//
// 1. `U.value` has correct size and alignment for a value of type `T`
// 2. The `U.value` constructor is not invoked since U's constructor does
// not
// do it explicitly.
// 3. The `U.value` destructor is invoked since U's destructor does it
// explicitly. This makes `U` a kind of RAII wrapper around non default
// constructible value of T, which is destructed when we leave the
// scope. We do need to destroy U.value, which is constructed by
// CommandLineFlag::Read even though we left it in a moved-from state
// after std::move.
//
// All of this serves to avoid requiring `T` being default constructible.
union U {
T value;
U() {}
~U() { value.~T(); }
};
U u;
absl::string_view Name() const { return internal.Name(); }
std::string Help() const { return internal.Help(); }
std::string Filename() const { return internal.Filename(); }
absl::flags_internal::CommandLineFlag internal;
void SetCallback(const flags_internal::FlagCallback mutation_callback) {
internal.SetCallback(mutation_callback);
this->Read(&u.value, &flags_internal::FlagOps<T>);
return std::move(u.value);
}
private:
// TODO(rogeeff): add these validations once UnparseFlag invocation is fixed
// for built-in types and when we cleanup existing code from operating on
// forward declared types.
// auto IsCopyConstructible(const T& v) -> decltype(T(v));
// auto HasAbslParseFlag(absl::string_view in, T* dst, std::string* err)
// -> decltype(AbslParseFlag(in, dst, err));
// auto HasAbslUnparseFlag(const T& v) -> decltype(AbslUnparseFlag(v));
bool AtomicGet(T* v) const {
const int64_t r = this->atomic.load(std::memory_order_acquire);
if (r != flags_internal::CommandLineFlag::kAtomicInit) {
memcpy(v, &r, sizeof(T));
return true;
}
return false;
}
void Set(const T& v) { this->Write(&v, &flags_internal::FlagOps<T>); }
};
// This class facilitates Flag object registration and tail expression-based
@ -67,7 +85,7 @@ template <typename T, bool do_register>
class FlagRegistrar {
public:
explicit FlagRegistrar(Flag<T>* flag) : flag_(flag) {
if (do_register) flags_internal::RegisterCommandLineFlag(&flag_->internal);
if (do_register) flags_internal::RegisterCommandLineFlag(flag_);
}
FlagRegistrar& OnUpdate(flags_internal::FlagCallback cb) && {

48
absl/flags/internal/registry.cc
View file

@ -34,13 +34,7 @@ namespace flags_internal {
namespace {
void DestroyFlag(CommandLineFlag* flag) NO_THREAD_SAFETY_ANALYSIS {
// Values are heap allocated for retired and Abseil Flags.
if (flag->IsRetired() || flag->IsAbseilFlag()) {
if (flag->cur) Delete(flag->op, flag->cur);
if (flag->def) Delete(flag->op, flag->def);
}
delete flag->locks;
flag->Destroy();
// CommandLineFlag handle object is heap allocated for non Abseil Flags.
if (!flag->IsAbseilFlag()) {
@ -48,6 +42,8 @@ void DestroyFlag(CommandLineFlag* flag) NO_THREAD_SAFETY_ANALYSIS {
}
}
} // namespace
// --------------------------------------------------------------------
// FlagRegistry
// A FlagRegistry singleton object holds all flag objects indexed
@ -105,8 +101,6 @@ class FlagPtrMap {
};
constexpr size_t FlagPtrMap::kNumBuckets;
} // namespace
class FlagRegistry {
public:
FlagRegistry() = default;
@ -292,10 +286,10 @@ class FlagSaverImpl {
saved.op = flag->op;
saved.marshalling_op = flag->marshalling_op;
{
absl::MutexLock l(InitFlagIfNecessary(flag));
absl::MutexLock l(flag->InitFlagIfNecessary());
saved.validator = flag->validator;
saved.modified = flag->modified;
saved.on_command_line = flag->IsSpecifiedOnCommandLine();
saved.on_command_line = flag->on_command_line;
saved.current = Clone(saved.op, flag->cur);
saved.default_value = Clone(saved.op, flag->def);
saved.counter = flag->counter;
@ -318,34 +312,34 @@ class FlagSaverImpl {
bool restored = false;
{
absl::Mutex* mu = InitFlagIfNecessary(flag);
absl::MutexLock l(mu);
absl::MutexLock l(flag->InitFlagIfNecessary());
flag->validator = src.validator;
flag->modified = src.modified;
flag->on_command_line = src.on_command_line;
if (flag->counter != src.counter ||
ChangedDirectly(flag, src.default_value, flag->def)) {
flag->counter++;
restored = true;
Copy(src.op, src.default_value, flag->def);
}
if (flag->counter != src.counter ||
ChangedDirectly(flag, src.current, flag->cur)) {
restored = true;
flag->counter++;
Copy(src.op, src.current, flag->cur);
UpdateCopy(flag, mu);
UpdateCopy(flag);
flag->InvokeCallback();
}
}
if (restored) {
flag->counter++;
// Revalidate the flag because the validator might store state based
// on the flag's value, which just changed due to the restore.
// Failing validation is ignored because it's assumed that the flag
// was valid previously and there's little that can be done about it
// here, anyway.
Validate(flag, flag->cur);
}
}
flag->ValidateInputValue(flag->CurrentValue());
// Log statements must be done when no flag lock is held.
if (restored) {
ABSL_INTERNAL_LOG(
INFO, absl::StrCat("Restore saved value of ", flag->Name(), ": ",
Unparse(src.marshalling_op, src.current)));
@ -412,13 +406,17 @@ void FillCommandLineFlagInfo(CommandLineFlag* flag,
result->description = flag->Help();
result->filename = flag->Filename();
UpdateModifiedBit(flag);
if (!flag->IsAbseilFlag()) {
if (!flag->IsModified() && ChangedDirectly(flag, flag->cur, flag->def)) {
flag->modified = true;
}
}
absl::MutexLock l(InitFlagIfNecessary(flag));
result->current_value = flag->CurrentValue();
result->default_value = flag->DefaultValue();
result->is_default = !flag->modified;
result->has_validator_fn = (flag->validator != nullptr);
result->is_default = !flag->IsModified();
result->has_validator_fn = flag->HasValidatorFn();
absl::MutexLock l(flag->InitFlagIfNecessary());
result->flag_ptr = flag->IsAbseilFlag() ? nullptr : flag->cur;
}

19
absl/flags/internal/type_erased.cc
View file

@ -32,7 +32,6 @@ bool GetCommandLineOption(absl::string_view name, std::string* value) {
return false;
}
absl::MutexLock l(InitFlagIfNecessary(flag));
*value = flag->CurrentValue();
return true;
}
@ -88,22 +87,9 @@ bool SetCommandLineOptionWithMode(absl::string_view name,
bool IsValidFlagValue(absl::string_view name, absl::string_view value) {
CommandLineFlag* flag = flags_internal::FindCommandLineFlag(name);
if (flag == nullptr) {
return false;
}
if (flag->IsRetired()) {
return true;
}
// No need to lock the flag since we are not mutating it.
void* obj = Clone(flag->op, flag->def);
std::string ignored_error;
const bool result =
flags_internal::Parse(flag->marshalling_op, value, obj, &ignored_error) &&
Validate(flag, obj);
Delete(flag->op, obj);
return result;
return flag != nullptr &&
(flag->IsRetired() || flag->ValidateInputValue(value));
}
// --------------------------------------------------------------------
@ -111,7 +97,6 @@ bool IsValidFlagValue(absl::string_view name, absl::string_view value) {
bool SpecifiedOnCommandLine(absl::string_view name) {
CommandLineFlag* flag = flags_internal::FindCommandLineFlag(name);
if (flag != nullptr && !flag->IsRetired()) {
absl::MutexLock l(InitFlagIfNecessary(flag));
return flag->IsSpecifiedOnCommandLine();
}
return false;

38
absl/flags/internal/usage.cc
View file

@ -21,11 +21,11 @@
#include "absl/flags/flag.h"
#include "absl/flags/internal/path_util.h"
#include "absl/flags/internal/program_name.h"
#include "absl/flags/usage.h"
#include "absl/flags/usage_config.h"
#include "absl/strings/ascii.h"
#include "absl/strings/str_cat.h"
#include "absl/strings/str_split.h"
#include "absl/strings/string_view.h"
#include "absl/synchronization/mutex.h"
ABSL_FLAG(bool, help, false,
@ -185,7 +185,7 @@ void FlagHelpHumanReadable(const flags_internal::CommandLineFlag& flag,
}
printer.Write(absl::StrCat("default: ", dflt_val, ";"));
if (flag.modified) {
if (flag.IsModified()) {
std::string curr_val = flag.CurrentValue();
if (flag.IsOfType<std::string>()) {
curr_val = absl::StrCat("\"", curr_val, "\"");
@ -202,10 +202,10 @@ void FlagHelpHumanReadable(const flags_internal::CommandLineFlag& flag,
// STRIP_FLAG_HELP 1' then this flag will not be displayed by '--help'
// and its variants.
void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb,
HelpFormat format = HelpFormat::kHumanReadable) {
HelpFormat format, absl::string_view program_usage_message) {
if (format == HelpFormat::kHumanReadable) {
out << flags_internal::ShortProgramInvocationName() << ": "
<< absl::ProgramUsageMessage() << "\n\n";
<< program_usage_message << "\n\n";
} else {
// XML schema is not a part of our public API for now.
out << "<?xml version=\"1.0\"?>\n"
@ -214,7 +214,7 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb,
// The program name and usage.
<< XMLElement("program", flags_internal::ShortProgramInvocationName())
<< '\n'
<< XMLElement("usage", absl::ProgramUsageMessage()) << '\n';
<< XMLElement("usage", program_usage_message) << '\n';
}
// Map of package name to
@ -228,8 +228,6 @@ void FlagsHelpImpl(std::ostream& out, flags_internal::FlagKindFilter filter_cb,
matching_flags;
flags_internal::ForEachFlag([&](flags_internal::CommandLineFlag* flag) {
absl::MutexLock l(InitFlagIfNecessary(flag));
std::string flag_filename = flag->Filename();
// Ignore retired flags.
@ -292,44 +290,51 @@ void FlagHelp(std::ostream& out, const flags_internal::CommandLineFlag& flag,
// --------------------------------------------------------------------
// Produces the help messages for all flags matching the filter.
// If filter is empty produces help messages for all flags.
void FlagsHelp(std::ostream& out, absl::string_view filter, HelpFormat format) {
void FlagsHelp(std::ostream& out, absl::string_view filter, HelpFormat format,
absl::string_view program_usage_message) {
flags_internal::FlagKindFilter filter_cb = [&](absl::string_view filename) {
return filter.empty() || filename.find(filter) != absl::string_view::npos;
};
flags_internal::FlagsHelpImpl(out, filter_cb, format);
flags_internal::FlagsHelpImpl(out, filter_cb, format, program_usage_message);
}
// --------------------------------------------------------------------
// Checks all the 'usage' command line flags to see if any have been set.
// If so, handles them appropriately.
int HandleUsageFlags(std::ostream& out) {
int HandleUsageFlags(std::ostream& out,
absl::string_view program_usage_message) {
if (absl::GetFlag(FLAGS_helpshort)) {
flags_internal::FlagsHelpImpl(
out, flags_internal::GetUsageConfig().contains_helpshort_flags,
HelpFormat::kHumanReadable);
HelpFormat::kHumanReadable, program_usage_message);
return 1;
}
if (absl::GetFlag(FLAGS_helpfull)) {
// show all options
flags_internal::FlagsHelp(out);
flags_internal::FlagsHelp(out, "", HelpFormat::kHumanReadable,
program_usage_message);
return 1;
}
if (!absl::GetFlag(FLAGS_helpon).empty()) {
flags_internal::FlagsHelp(
out, absl::StrCat("/", absl::GetFlag(FLAGS_helpon), "."));
out, absl::StrCat("/", absl::GetFlag(FLAGS_helpon), "."),
HelpFormat::kHumanReadable, program_usage_message);
return 1;
}
if (!absl::GetFlag(FLAGS_helpmatch).empty()) {
flags_internal::FlagsHelp(out, absl::GetFlag(FLAGS_helpmatch));
flags_internal::FlagsHelp(out, absl::GetFlag(FLAGS_helpmatch),
HelpFormat::kHumanReadable,
program_usage_message);
return 1;
}
if (absl::GetFlag(FLAGS_help)) {
flags_internal::FlagsHelpImpl(
out, flags_internal::GetUsageConfig().contains_help_flags);
out, flags_internal::GetUsageConfig().contains_help_flags,
HelpFormat::kHumanReadable, program_usage_message);
out << "\nTry --helpfull to get a list of all flags.\n";
@ -338,7 +343,8 @@ int HandleUsageFlags(std::ostream& out) {
if (absl::GetFlag(FLAGS_helppackage)) {
flags_internal::FlagsHelpImpl(
out, flags_internal::GetUsageConfig().contains_helppackage_flags);
out, flags_internal::GetUsageConfig().contains_helppackage_flags,
HelpFormat::kHumanReadable, program_usage_message);
out << "\nTry --helpfull to get a list of all flags.\n";

7
absl/flags/internal/usage.h
View file

@ -47,8 +47,8 @@ void FlagHelp(std::ostream& out, const flags_internal::CommandLineFlag& flag,
// .../path/to/file.<ext>
// for any extension 'ext'. If the filter is empty this function produces help
// messages for all flags.
void FlagsHelp(std::ostream& out, absl::string_view filter = {},
HelpFormat format = HelpFormat::kHumanReadable);
void FlagsHelp(std::ostream& out, absl::string_view filter,
HelpFormat format, absl::string_view program_usage_message);
// --------------------------------------------------------------------
@ -60,7 +60,8 @@ void FlagsHelp(std::ostream& out, absl::string_view filter = {},
// -1 - if no usage flags were set on a commmand line.
// Non negative return values are expected to be used as an exit code for a
// binary.
int HandleUsageFlags(std::ostream& out);
int HandleUsageFlags(std::ostream& out,
absl::string_view program_usage_message);
} // namespace flags_internal
} // namespace absl

38
absl/flags/internal/usage_test.cc
View file

@ -36,6 +36,8 @@ ABSL_FLAG(double, usage_reporting_test_flag_03, 1.03,
ABSL_FLAG(int64_t, usage_reporting_test_flag_04, 1000000000000004L,
"usage_reporting_test_flag_04 help message");
static const char kTestUsageMessage[] = "Custom usage message";
struct UDT {
UDT() = default;
UDT(const UDT&) = default;
@ -83,7 +85,7 @@ class UsageReportingTest : public testing::Test {
using UsageReportingDeathTest = UsageReportingTest;
TEST_F(UsageReportingDeathTest, TestSetProgramUsageMessage) {
EXPECT_EQ(absl::ProgramUsageMessage(), "Custom usage message");
EXPECT_EQ(absl::ProgramUsageMessage(), kTestUsageMessage);
#ifndef _WIN32
// TODO(rogeeff): figure out why this does not work on Windows.
@ -175,22 +177,22 @@ TEST_F(UsageReportingTest, TestFlagsHelpHRF) {
std::stringstream test_buf_01;
flags::FlagsHelp(test_buf_01, "usage_test.cc",
flags::HelpFormat::kHumanReadable);
flags::HelpFormat::kHumanReadable, kTestUsageMessage);
EXPECT_EQ(test_buf_01.str(), usage_test_flags_out);
std::stringstream test_buf_02;
flags::FlagsHelp(test_buf_02, "flags/internal/usage_test.cc",
flags::HelpFormat::kHumanReadable);
flags::HelpFormat::kHumanReadable, kTestUsageMessage);
EXPECT_EQ(test_buf_02.str(), usage_test_flags_out);
std::stringstream test_buf_03;
flags::FlagsHelp(test_buf_03, "usage_test",
flags::HelpFormat::kHumanReadable);
flags::FlagsHelp(test_buf_03, "usage_test", flags::HelpFormat::kHumanReadable,
kTestUsageMessage);
EXPECT_EQ(test_buf_03.str(), usage_test_flags_out);
std::stringstream test_buf_04;
flags::FlagsHelp(test_buf_04, "flags/invalid_file_name.cc",
flags::HelpFormat::kHumanReadable);
flags::HelpFormat::kHumanReadable, kTestUsageMessage);
EXPECT_EQ(test_buf_04.str(),
R"(usage_test: Custom usage message
@ -198,7 +200,8 @@ TEST_F(UsageReportingTest, TestFlagsHelpHRF) {
)");
std::stringstream test_buf_05;
flags::FlagsHelp(test_buf_05, "", flags::HelpFormat::kHumanReadable);
flags::FlagsHelp(test_buf_05, "", flags::HelpFormat::kHumanReadable,
kTestUsageMessage);
std::string test_out = test_buf_05.str();
absl::string_view test_out_str(test_out);
EXPECT_TRUE(
@ -217,7 +220,7 @@ TEST_F(UsageReportingTest, TestFlagsHelpHRF) {
TEST_F(UsageReportingTest, TestNoUsageFlags) {
std::stringstream test_buf;
EXPECT_EQ(flags::HandleUsageFlags(test_buf), -1);
EXPECT_EQ(flags::HandleUsageFlags(test_buf, kTestUsageMessage), -1);
}
// --------------------------------------------------------------------
@ -226,7 +229,7 @@ TEST_F(UsageReportingTest, TestUsageFlag_helpshort) {
absl::SetFlag(&FLAGS_helpshort, true);
std::stringstream test_buf;
EXPECT_EQ(flags::HandleUsageFlags(test_buf), 1);
EXPECT_EQ(flags::HandleUsageFlags(test_buf, kTestUsageMessage), 1);
EXPECT_EQ(test_buf.str(),
R"(usage_test: Custom usage message
@ -250,7 +253,7 @@ TEST_F(UsageReportingTest, TestUsageFlag_help) {
absl::SetFlag(&FLAGS_help, true);
std::stringstream test_buf;
EXPECT_EQ(flags::HandleUsageFlags(test_buf), 1);
EXPECT_EQ(flags::HandleUsageFlags(test_buf, kTestUsageMessage), 1);
EXPECT_EQ(test_buf.str(),
R"(usage_test: Custom usage message
@ -276,7 +279,7 @@ TEST_F(UsageReportingTest, TestUsageFlag_helppackage) {
absl::SetFlag(&FLAGS_helppackage, true);
std::stringstream test_buf;
EXPECT_EQ(flags::HandleUsageFlags(test_buf), 1);
EXPECT_EQ(flags::HandleUsageFlags(test_buf, kTestUsageMessage), 1);
EXPECT_EQ(test_buf.str(),
R"(usage_test: Custom usage message
@ -302,10 +305,9 @@ TEST_F(UsageReportingTest, TestUsageFlag_version) {
absl::SetFlag(&FLAGS_version, true);
std::stringstream test_buf;
EXPECT_EQ(flags::HandleUsageFlags(test_buf), 0);
EXPECT_EQ(flags::HandleUsageFlags(test_buf, kTestUsageMessage), 0);
#ifndef NDEBUG
EXPECT_EQ(test_buf.str(),
"usage_test\nDebug build (NDEBUG not #defined)\n");
EXPECT_EQ(test_buf.str(), "usage_test\nDebug build (NDEBUG not #defined)\n");
#else
EXPECT_EQ(test_buf.str(), "usage_test\n");
#endif
@ -317,7 +319,7 @@ TEST_F(UsageReportingTest, TestUsageFlag_only_check_args) {
absl::SetFlag(&FLAGS_only_check_args, true);
std::stringstream test_buf;
EXPECT_EQ(flags::HandleUsageFlags(test_buf), 0);
EXPECT_EQ(flags::HandleUsageFlags(test_buf, kTestUsageMessage), 0);
EXPECT_EQ(test_buf.str(), "");
}
@ -327,7 +329,7 @@ TEST_F(UsageReportingTest, TestUsageFlag_helpon) {
absl::SetFlag(&FLAGS_helpon, "bla-bla");
std::stringstream test_buf_01;
EXPECT_EQ(flags::HandleUsageFlags(test_buf_01), 1);
EXPECT_EQ(flags::HandleUsageFlags(test_buf_01, kTestUsageMessage), 1);
EXPECT_EQ(test_buf_01.str(),
R"(usage_test: Custom usage message
@ -337,7 +339,7 @@ TEST_F(UsageReportingTest, TestUsageFlag_helpon) {
absl::SetFlag(&FLAGS_helpon, "usage_test");
std::stringstream test_buf_02;
EXPECT_EQ(flags::HandleUsageFlags(test_buf_02), 1);
EXPECT_EQ(flags::HandleUsageFlags(test_buf_02, kTestUsageMessage), 1);
EXPECT_EQ(test_buf_02.str(),
R"(usage_test: Custom usage message
@ -362,7 +364,7 @@ TEST_F(UsageReportingTest, TestUsageFlag_helpon) {
int main(int argc, char* argv[]) {
absl::GetFlag(FLAGS_undefok); // Force linking of parse.cc
flags::SetProgramInvocationName("usage_test");
absl::SetProgramUsageMessage("Custom usage message");
absl::SetProgramUsageMessage(kTestUsageMessage);
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();

25
absl/flags/parse.cc
View file

@ -16,6 +16,7 @@
#include "absl/flags/parse.h"
#include <stdlib.h>
#include <fstream>
#include <iostream>
#include <tuple>
@ -28,6 +29,7 @@
#include "absl/flags/internal/program_name.h"
#include "absl/flags/internal/registry.h"
#include "absl/flags/internal/usage.h"
#include "absl/flags/usage.h"
#include "absl/flags/usage_config.h"
#include "absl/strings/str_cat.h"
#include "absl/strings/strip.h"
@ -280,22 +282,7 @@ void CheckDefaultValuesParsingRoundtrip() {
IGNORE_TYPE(std::vector<std::string>)
#undef IGNORE_TYPE
absl::MutexLock lock(InitFlagIfNecessary(flag));
std::string v = flag->DefaultValue();
void* dst = Clone(flag->op, flag->def);
std::string error;
if (!flags_internal::Parse(flag->marshalling_op, v, dst, &error)) {
ABSL_INTERNAL_LOG(
FATAL,
absl::StrCat("Flag ", flag->Name(), " (from ", flag->Filename(),
"): std::string form of default value '", v,
"' could not be parsed; error=", error));
}
// We do not compare dst to def since parsing/unparsing may make
// small changes, e.g., precision loss for floating point types.
Delete(flag->op, dst);
flag->CheckDefaultValueParsingRoundtrip();
});
#endif
}
@ -717,12 +704,14 @@ std::vector<char*> ParseCommandLineImpl(int argc, char* argv[],
#endif
if (!success) {
flags_internal::HandleUsageFlags(std::cout);
flags_internal::HandleUsageFlags(std::cout,
ProgramUsageMessage());
std::exit(1);
}
if (usage_flag_act == UsageFlagsAction::kHandleUsage) {
int exit_code = flags_internal::HandleUsageFlags(std::cout);
int exit_code = flags_internal::HandleUsageFlags(
std::cout, ProgramUsageMessage());
if (exit_code != -1) {
std::exit(exit_code);

1
absl/hash/hash_test.cc
View file

@ -288,7 +288,6 @@ TEST(HashValueTest, Strings) {
// Also check that nested types maintain the same hash.
const WrapInTuple t{};
EXPECT_TRUE(absl::VerifyTypeImplementsAbslHashCorrectly(std::make_tuple(
//
t(std::string()), t(absl::string_view()),
t(std::string("")), t(absl::string_view("")),
t(std::string(small)), t(absl::string_view(small)),

3
absl/hash/internal/hash.h
View file

@ -640,7 +640,8 @@ class CityHashState : public HashStateBase<CityHashState> {
#endif // ABSL_HAVE_INTRINSIC_INT128
static constexpr uint64_t kMul =
sizeof(size_t) == 4 ? uint64_t{0xcc9e2d51} : uint64_t{0x9ddfea08eb382d69};
sizeof(size_t) == 4 ? uint64_t{0xcc9e2d51}
: uint64_t{0x9ddfea08eb382d69};
template <typename T>
using IntegralFastPath =

4
absl/numeric/int128.h
View file

@ -19,8 +19,8 @@
//
// This header file defines 128-bit integer types.
//
// Currently, this file defines `uint128`, an unsigned 128-bit integer; a signed
// 128-bit integer is forthcoming.
// Currently, this file defines `uint128`, an unsigned 128-bit integer;
// a signed 128-bit integer is forthcoming.
#ifndef ABSL_NUMERIC_INT128_H_
#define ABSL_NUMERIC_INT128_H_

347
absl/random/internal/fast_uniform_bits.h
View file

@ -22,11 +22,18 @@
namespace absl {
namespace random_internal {
// Returns true if the input value is zero or a power of two. Useful for
// determining if the range of output values in a URBG
template <typename UIntType>
constexpr bool IsPowerOfTwoOrZero(UIntType n) {
return (n == 0) || ((n & (n - 1)) == 0);
}
// Computes the length of the range of values producible by the URBG, or returns
// zero if that would encompass the entire range of representable values in
// URBG::result_type.
template <typename URBG>
constexpr typename URBG::result_type constexpr_range() {
constexpr typename URBG::result_type RangeSize() {
using result_type = typename URBG::result_type;
return ((URBG::max)() == (std::numeric_limits<result_type>::max)() &&
(URBG::min)() == std::numeric_limits<result_type>::lowest())
@ -34,6 +41,42 @@ constexpr typename URBG::result_type constexpr_range() {
: (URBG::max)() - (URBG::min)() + result_type{1};
}
template <typename UIntType>
constexpr UIntType LargestPowerOfTwoLessThanOrEqualTo(UIntType n) {
return n < 2 ? n : 2 * LargestPowerOfTwoLessThanOrEqualTo(n / 2);
}
// Given a URBG generating values in the closed interval [Lo, Hi], returns the
// largest power of two less than or equal to `Hi - Lo + 1`.
template <typename URBG>
constexpr typename URBG::result_type PowerOfTwoSubRangeSize() {
return LargestPowerOfTwoLessThanOrEqualTo(RangeSize<URBG>());
}
// Computes the floor of the log. (i.e., std::floor(std::log2(N));
template <typename UIntType>
constexpr UIntType IntegerLog2(UIntType n) {
return (n <= 1) ? 0 : 1 + IntegerLog2(n / 2);
}
// Returns the number of bits of randomness returned through
// `PowerOfTwoVariate(urbg)`.
template <typename URBG>
constexpr size_t NumBits() {
return RangeSize<URBG>() == 0
? std::numeric_limits<typename URBG::result_type>::digits
: IntegerLog2(PowerOfTwoSubRangeSize<URBG>());
}
// Given a shift value `n`, constructs a mask with exactly the low `n` bits set.
// If `n == 0`, all bits are set.
template <typename UIntType>
constexpr UIntType MaskFromShift(UIntType n) {
return ((n % std::numeric_limits<UIntType>::digits) == 0)
? ~UIntType{0}
: (UIntType{1} << n) - UIntType{1};
}
// FastUniformBits implements a fast path to acquire uniform independent bits
// from a type which conforms to the [rand.req.urbg] concept.
// Parameterized by:
@ -45,14 +88,6 @@ constexpr typename URBG::result_type constexpr_range() {
// generator that will outlive the std::independent_bits_engine instance.
template <typename UIntType = uint64_t>
class FastUniformBits {
static_assert(std::is_unsigned<UIntType>::value,
"Class-template FastUniformBits<> must be parameterized using "
"an unsigned type.");
// `kWidth` is the width, in binary digits, of the output. By default it is
// the number of binary digits in the `result_type`.
static constexpr size_t kWidth = std::numeric_limits<UIntType>::digits;
public:
using result_type = UIntType;
@ -65,14 +100,47 @@ class FastUniformBits {
result_type operator()(URBG& g); // NOLINT(runtime/references)
private:
// Variate() generates a single random variate, always returning a value
// in the closed interval [0 ... FastUniformBitsURBGConstants::kRangeMask]
// (kRangeMask+1 is a power of 2).
template <typename URBG>
typename URBG::result_type Variate(URBG& g); // NOLINT(runtime/references)
static_assert(std::is_unsigned<UIntType>::value,
"Class-template FastUniformBits<> must be parameterized using "
"an unsigned type.");
// generate() generates a random value, dispatched on whether
// the underlying URNG must loop over multiple calls or not.
// PowerOfTwoVariate() generates a single random variate, always returning a
// value in the half-open interval `[0, PowerOfTwoSubRangeSize<URBG>())`. If
// the URBG already generates values in a power-of-two range, the generator
// itself is used. Otherwise, we use rejection sampling on the largest
// possible power-of-two-sized subrange.
struct PowerOfTwoTag {};
struct RejectionSamplingTag {};
template <typename URBG>
static typename URBG::result_type PowerOfTwoVariate(
URBG& g) { // NOLINT(runtime/references)
using tag =
typename std::conditional<IsPowerOfTwoOrZero(RangeSize<URBG>()),
PowerOfTwoTag, RejectionSamplingTag>::type;
return PowerOfTwoVariate(g, tag{});
}
template <typename URBG>
static typename URBG::result_type PowerOfTwoVariate(
URBG& g, // NOLINT(runtime/references)
PowerOfTwoTag) {
return g() - (URBG::min)();
}
template <typename URBG>
static typename URBG::result_type PowerOfTwoVariate(
URBG& g, // NOLINT(runtime/references)
RejectionSamplingTag) {
// Use rejection sampling to ensure uniformity across the range.
typename URBG::result_type u;
do {
u = g() - (URBG::min)();
} while (u >= PowerOfTwoSubRangeSize<URBG>());
return u;
}
// Generate() generates a random value, dispatched on whether
// the underlying URBG must loop over multiple calls or not.
template <typename URBG>
result_type Generate(URBG& g, // NOLINT(runtime/references)
std::true_type /* avoid_looping */);
@ -82,196 +150,107 @@ class FastUniformBits {
std::false_type /* avoid_looping */);
};
// FastUniformBitsURBGConstants computes the URBG-derived constants used
// by FastUniformBits::Generate and FastUniformBits::Variate.
// Parameterized by the FastUniformBits parameter:
// `URBG`: The underlying UniformRandomNumberGenerator.
//
// The values here indicate the URBG range as well as providing an indicator
// whether the URBG output is a power of 2, and kRangeMask, which allows masking
// the generated output to kRangeBits.
template <typename UIntType>
template <typename URBG>
class FastUniformBitsURBGConstants {
// Computes the floor of the log. (i.e., std::floor(std::log2(N));
static constexpr size_t constexpr_log2(size_t n) {
return (n <= 1) ? 0 : 1 + constexpr_log2(n / 2);
}
// Computes a mask of n bits for the URBG::result_type.
static constexpr typename URBG::result_type constexpr_mask(size_t n) {
return (typename URBG::result_type(1) << n) - 1;
}
public:
using result_type = typename URBG::result_type;
// The range of the URNG, max - min + 1, or zero if that result would cause
// overflow.
static constexpr result_type kRange = constexpr_range<URBG>();
static constexpr bool kPowerOfTwo =
(kRange == 0) || ((kRange & (kRange - 1)) == 0);
// kRangeBits describes the number number of bits suitable to mask off of URNG
// variate, which is:
// kRangeBits = floor(log2(kRange))
static constexpr size_t kRangeBits =
kRange == 0 ? std::numeric_limits<result_type>::digits
: constexpr_log2(kRange);
// kRangeMask is the mask used when sampling variates from the URNG when the
// width of the URNG range is not a power of 2.
typename FastUniformBits<UIntType>::result_type
FastUniformBits<UIntType>::operator()(URBG& g) { // NOLINT(runtime/references)
// kRangeMask is the mask used when sampling variates from the URBG when the
// width of the URBG range is not a power of 2.
// Y = (2 ^ kRange) - 1
static constexpr result_type kRangeMask =
kRange == 0 ? (std::numeric_limits<result_type>::max)()
: constexpr_mask(kRangeBits);
static_assert((URBG::max)() != (URBG::min)(),
"Class-template FastUniformBitsURBGConstants<> "
static_assert((URBG::max)() > (URBG::min)(),
"URBG::max and URBG::min may not be equal.");
static_assert(std::is_unsigned<result_type>::value,
"Class-template FastUniformBitsURBGConstants<> "
"URBG::result_type must be unsigned.");
static_assert(kRangeMask > 0,
"Class-template FastUniformBitsURBGConstants<> "
"URBG does not generate sufficient random bits.");
static_assert(kRange == 0 ||
kRangeBits < std::numeric_limits<result_type>::digits,
"Class-template FastUniformBitsURBGConstants<> "
"URBG range computation error.");
};
// FastUniformBitsLoopingConstants computes the looping constants used
// by FastUniformBits::Generate. These constants indicate how multiple
// URBG::result_type values are combined into an output_value.
// Parameterized by the FastUniformBits parameters:
// `UIntType`: output type.
// `URNG`: The underlying UniformRandomNumberGenerator.
//
// The looping constants describe the sets of loop counters and mask values
// which control how individual variates are combined the final output. The
// algorithm ensures that the number of bits used by any individual call differs
// by at-most one bit from any other call. This is simplified into constants
// which describe two loops, with the second loop parameters providing one extra
// bit per variate.
//
// See [rand.adapt.ibits] for more details on the use of these constants.
template <typename UIntType, typename URBG>
class FastUniformBitsLoopingConstants {
private:
static constexpr size_t kWidth = std::numeric_limits<UIntType>::digits;
using urbg_result_type = typename URBG::result_type;
using uint_result_type = UIntType;
public:
using result_type =
typename std::conditional<(sizeof(urbg_result_type) <=
sizeof(uint_result_type)),
uint_result_type, urbg_result_type>::type;
private:
// Estimate N as ceil(width / urng width), and W0 as (width / N).
static constexpr size_t kRangeBits =
FastUniformBitsURBGConstants<URBG>::kRangeBits;
// The range of the URNG, max - min + 1, or zero if that result would cause
// overflow.
static constexpr result_type kRange = constexpr_range<URBG>();
static constexpr size_t kEstimateN =
kWidth / kRangeBits + (kWidth % kRangeBits != 0);
static constexpr size_t kEstimateW0 = kWidth / kEstimateN;
static constexpr result_type kEstimateY0 = (kRange >> kEstimateW0)
<< kEstimateW0;
public:
// Parameters for the two loops:
// kN0, kN1 are the number of underlying calls required for each loop.
// KW0, kW1 are shift widths for each loop.
//
static constexpr size_t kN1 = (kRange - kEstimateY0) >
(kEstimateY0 / kEstimateN)
? kEstimateN + 1
: kEstimateN;
static constexpr size_t kN0 = kN1 - (kWidth % kN1);
static constexpr size_t kW0 = kWidth / kN1;
static constexpr size_t kW1 = kW0 + 1;
static constexpr result_type kM0 = (result_type(1) << kW0) - 1;
static constexpr result_type kM1 = (result_type(1) << kW1) - 1;
static_assert(
kW0 <= kRangeBits,
"Class-template FastUniformBitsLoopingConstants::kW0 too large.");
static_assert(
kW0 > 0,
"Class-template FastUniformBitsLoopingConstants::kW0 too small.");
};
template <typename UIntType>
template <typename URBG>
typename FastUniformBits<UIntType>::result_type
FastUniformBits<UIntType>::operator()(
URBG& g) { // NOLINT(runtime/references)
using constants = FastUniformBitsURBGConstants<URBG>;
return Generate(
g, std::integral_constant<bool, constants::kRangeMask >= (max)()>{});
}
template <typename UIntType>
template <typename URBG>
typename URBG::result_type FastUniformBits<UIntType>::Variate(
URBG& g) { // NOLINT(runtime/references)
using constants = FastUniformBitsURBGConstants<URBG>;
if (constants::kPowerOfTwo) {
return g() - (URBG::min)();
}
// Use rejection sampling to ensure uniformity across the range.
typename URBG::result_type u;
do {
u = g() - (URBG::min)();
} while (u > constants::kRangeMask);
return u;
constexpr urbg_result_type kRangeMask =
RangeSize<URBG>() == 0
? (std::numeric_limits<urbg_result_type>::max)()
: static_cast<urbg_result_type>(PowerOfTwoSubRangeSize<URBG>() - 1);
return Generate(g, std::integral_constant<bool, (kRangeMask >= (max)())>{});
}
template <typename UIntType>
template <typename URBG>
typename FastUniformBits<UIntType>::result_type
FastUniformBits<UIntType>::Generate(
URBG& g, // NOLINT(runtime/references)
FastUniformBits<UIntType>::Generate(URBG& g, // NOLINT(runtime/references)
std::true_type /* avoid_looping */) {
// The width of the result_type is less than than the width of the random bits
// provided by URNG. Thus, generate a single value and then simply mask off
// provided by URBG. Thus, generate a single value and then simply mask off
// the required bits.
return Variate(g) & (max)();
return PowerOfTwoVariate(g) & (max)();
}
template <typename UIntType>
template <typename URBG>
typename FastUniformBits<UIntType>::result_type
FastUniformBits<UIntType>::Generate(
URBG& g, // NOLINT(runtime/references)
FastUniformBits<UIntType>::Generate(URBG& g, // NOLINT(runtime/references)
std::false_type /* avoid_looping */) {
// The width of the result_type is wider than the number of random bits
// provided by URNG. Thus we merge several variates of URNG into the result
// using a shift and mask. The constants type generates the parameters used
// ensure that the bits are distributed across all the invocations of the
// underlying URNG.
using constants = FastUniformBitsLoopingConstants<UIntType, URBG>;
// See [rand.adapt.ibits] for more details on the constants calculated below.
//
// It is preferable to use roughly the same number of bits from each generator
// call, however this is only possible when the number of bits provided by the
// URBG is a divisor of the number of bits in `result_type`. In all other
// cases, the number of bits used cannot always be the same, but it can be
// guaranteed to be off by at most 1. Thus we run two loops, one with a
// smaller bit-width size (`kSmallWidth`) and one with a larger width size
// (satisfying `kLargeWidth == kSmallWidth + 1`). The loops are run
// `kSmallIters` and `kLargeIters` times respectively such
// that
//
// `kTotalWidth == kSmallIters * kSmallWidth
// + kLargeIters * kLargeWidth`
//
// where `kTotalWidth` is the total number of bits in `result_type`.
//
constexpr size_t kTotalWidth = std::numeric_limits<result_type>::digits;
constexpr size_t kUrbgWidth = NumBits<URBG>();
constexpr size_t kTotalIters =
kTotalWidth / kUrbgWidth + (kTotalWidth % kUrbgWidth != 0);
constexpr size_t kSmallWidth = kTotalWidth / kTotalIters;
constexpr size_t kLargeWidth = kSmallWidth + 1;
//
// Because `kLargeWidth == kSmallWidth + 1`, it follows that
//
// `kTotalWidth == kTotalIters * kSmallWidth + kLargeIters`
//
// and therefore
//
// `kLargeIters == kTotalWidth % kSmallWidth`
//
// Intuitively, each iteration with the large width accounts for one unit
// of the remainder when `kTotalWidth` is divided by `kSmallWidth`. As
// mentioned above, if the URBG width is a divisor of `kTotalWidth`, then
// there would be no need for any large iterations (i.e., one loop would
// suffice), and indeed, in this case, `kLargeIters` would be zero.
constexpr size_t kLargeIters = kTotalWidth % kSmallWidth;
constexpr size_t kSmallIters =
(kTotalWidth - (kLargeWidth * kLargeIters)) / kSmallWidth;
static_assert(
kTotalWidth == kSmallIters * kSmallWidth + kLargeIters * kLargeWidth,
"Error in looping constant calculations.");
result_type s = 0;
for (size_t n = 0; n < constants::kN0; ++n) {
auto u = Variate(g);
s = (s << constants::kW0) + (u & constants::kM0);
constexpr size_t kSmallShift = kSmallWidth % kTotalWidth;
constexpr result_type kSmallMask = MaskFromShift(result_type{kSmallShift});
for (size_t n = 0; n < kSmallIters; ++n) {
s = (s << kSmallShift) +
(static_cast<result_type>(PowerOfTwoVariate(g)) & kSmallMask);
}
for (size_t n = constants::kN0; n < constants::kN1; ++n) {
auto u = Variate(g);
s = (s << constants::kW1) + (u & constants::kM1);
constexpr size_t kLargeShift = kLargeWidth % kTotalWidth;
constexpr result_type kLargeMask = MaskFromShift(result_type{kLargeShift});
for (size_t n = 0; n < kLargeIters; ++n) {
s = (s << kLargeShift) +
(static_cast<result_type>(PowerOfTwoVariate(g)) & kLargeMask);
}
static_assert(
kLargeShift == kSmallShift + 1 ||
(kLargeShift == 0 &&
kSmallShift == std::numeric_limits<result_type>::digits - 1),
"Error in looping constant calculations");
return s;
}

237
absl/random/internal/fast_uniform_bits_test.cc
View file

@ -18,6 +18,8 @@
#include "gtest/gtest.h"
namespace absl {
namespace random_internal {
namespace {
template <typename IntType>
@ -29,7 +31,7 @@ TYPED_TEST_SUITE(FastUniformBitsTypedTest, IntTypes);
TYPED_TEST(FastUniformBitsTypedTest, BasicTest) {
using Limits = std::numeric_limits<TypeParam>;
using FastBits = absl::random_internal::FastUniformBits<TypeParam>;
using FastBits = FastUniformBits<TypeParam>;
EXPECT_EQ(0, FastBits::min());
EXPECT_EQ(Limits::max(), FastBits::max());
@ -45,91 +47,226 @@ TYPED_TEST(FastUniformBitsTypedTest, BasicTest) {
}
}
class UrngOddbits {
public:
using result_type = uint8_t;
static constexpr result_type min() { return 1; }
static constexpr result_type max() { return 0xfe; }
result_type operator()() { return 2; }
template <typename UIntType, UIntType Lo, UIntType Hi, UIntType Val = Lo>
struct FakeUrbg {
using result_type = UIntType;
static constexpr result_type(max)() { return Hi; }
static constexpr result_type(min)() { return Lo; }
result_type operator()() { return Val; }
};
class Urng4bits {
public:
using result_type = uint8_t;
static constexpr result_type min() { return 1; }
static constexpr result_type max() { return 0xf + 1; }
result_type operator()() { return 2; }
};
using UrngOddbits = FakeUrbg<uint8_t, 1, 0xfe, 0x73>;
using Urng4bits = FakeUrbg<uint8_t, 1, 0x10, 2>;
using Urng31bits = FakeUrbg<uint32_t, 1, 0xfffffffe, 0x60070f03>;
using Urng32bits = FakeUrbg<uint32_t, 0, 0xffffffff, 0x74010f01>;
class Urng32bits {
public:
using result_type = uint32_t;
static constexpr result_type min() { return 0; }
static constexpr result_type max() { return 0xffffffff; }
result_type operator()() { return 1; }
};
TEST(FastUniformBitsTest, IsPowerOfTwoOrZero) {
EXPECT_TRUE(IsPowerOfTwoOrZero(uint8_t{0}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint8_t{1}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint8_t{2}));
EXPECT_FALSE(IsPowerOfTwoOrZero(uint8_t{3}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint8_t{16}));
EXPECT_FALSE(IsPowerOfTwoOrZero(uint8_t{17}));
EXPECT_FALSE(IsPowerOfTwoOrZero((std::numeric_limits<uint8_t>::max)()));
// Compile-time test to validate the helper classes used by FastUniformBits
TEST(FastUniformBitsTest, FastUniformBitsDetails) {
using absl::random_internal::FastUniformBitsLoopingConstants;
using absl::random_internal::FastUniformBitsURBGConstants;
EXPECT_TRUE(IsPowerOfTwoOrZero(uint16_t{0}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint16_t{1}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint16_t{2}));
EXPECT_FALSE(IsPowerOfTwoOrZero(uint16_t{3}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint16_t{16}));
EXPECT_FALSE(IsPowerOfTwoOrZero(uint16_t{17}));
EXPECT_FALSE(IsPowerOfTwoOrZero((std::numeric_limits<uint16_t>::max)()));
// 4-bit URBG
{
using constants = FastUniformBitsURBGConstants<Urng4bits>;
static_assert(constants::kPowerOfTwo == true,
"constants::kPowerOfTwo == false");
static_assert(constants::kRange == 16, "constants::kRange == false");
static_assert(constants::kRangeBits == 4, "constants::kRangeBits == false");
static_assert(constants::kRangeMask == 0x0f,
"constants::kRangeMask == false");
EXPECT_TRUE(IsPowerOfTwoOrZero(uint32_t{0}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint32_t{1}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint32_t{2}));
EXPECT_FALSE(IsPowerOfTwoOrZero(uint32_t{3}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint32_t{32}));
EXPECT_FALSE(IsPowerOfTwoOrZero(uint32_t{17}));
EXPECT_FALSE(IsPowerOfTwoOrZero((std::numeric_limits<uint32_t>::max)()));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint64_t{0}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint64_t{1}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint64_t{2}));
EXPECT_FALSE(IsPowerOfTwoOrZero(uint64_t{3}));
EXPECT_TRUE(IsPowerOfTwoOrZero(uint64_t{64}));
EXPECT_FALSE(IsPowerOfTwoOrZero(uint64_t{17}));
EXPECT_FALSE(IsPowerOfTwoOrZero((std::numeric_limits<uint64_t>::max)()));
}
// ~7-bit URBG
{
using constants = FastUniformBitsURBGConstants<UrngOddbits>;
static_assert(constants::kPowerOfTwo == false,
"constants::kPowerOfTwo == false");
static_assert(constants::kRange == 0xfe, "constants::kRange == 0xfe");
static_assert(constants::kRangeBits == 7, "constants::kRangeBits == 7");
static_assert(constants::kRangeMask == 0x7f,
"constants::kRangeMask == 0x7f");
TEST(FastUniformBitsTest, IntegerLog2) {
EXPECT_EQ(IntegerLog2(uint16_t{0}), 0);
EXPECT_EQ(IntegerLog2(uint16_t{1}), 0);
EXPECT_EQ(IntegerLog2(uint16_t{2}), 1);
EXPECT_EQ(IntegerLog2(uint16_t{3}), 1);
EXPECT_EQ(IntegerLog2(uint16_t{4}), 2);
EXPECT_EQ(IntegerLog2(uint16_t{5}), 2);
EXPECT_EQ(IntegerLog2(std::numeric_limits<uint64_t>::max()), 63);
}
TEST(FastUniformBitsTest, RangeSize) {
EXPECT_EQ((RangeSize<FakeUrbg<uint8_t, 0, 3>>()), 4);
EXPECT_EQ((RangeSize<FakeUrbg<uint8_t, 2, 2>>()), 1);
EXPECT_EQ((RangeSize<FakeUrbg<uint8_t, 2, 5>>()), 4);
EXPECT_EQ((RangeSize<FakeUrbg<uint8_t, 2, 6>>()), 5);
EXPECT_EQ((RangeSize<FakeUrbg<uint8_t, 2, 10>>()), 9);
EXPECT_EQ(
(RangeSize<FakeUrbg<uint8_t, 0, std::numeric_limits<uint8_t>::max()>>()),
0);
EXPECT_EQ((RangeSize<FakeUrbg<uint16_t, 0, 3>>()), 4);
EXPECT_EQ((RangeSize<FakeUrbg<uint16_t, 2, 2>>()), 1);
EXPECT_EQ((RangeSize<FakeUrbg<uint16_t, 2, 5>>()), 4);
EXPECT_EQ((RangeSize<FakeUrbg<uint16_t, 2, 6>>()), 5);
EXPECT_EQ((RangeSize<FakeUrbg<uint16_t, 1000, 1017>>()), 18);
EXPECT_EQ((RangeSize<
FakeUrbg<uint16_t, 0, std::numeric_limits<uint16_t>::max()>>()),
0);
EXPECT_EQ((RangeSize<FakeUrbg<uint32_t, 0, 3>>()), 4);
EXPECT_EQ((RangeSize<FakeUrbg<uint32_t, 2, 2>>()), 1);
EXPECT_EQ((RangeSize<FakeUrbg<uint32_t, 2, 5>>()), 4);
EXPECT_EQ((RangeSize<FakeUrbg<uint32_t, 2, 6>>()), 5);
EXPECT_EQ((RangeSize<FakeUrbg<uint32_t, 1000, 1017>>()), 18);
EXPECT_EQ((RangeSize<FakeUrbg<uint32_t, 0, 0xffffffff>>()), 0);
EXPECT_EQ((RangeSize<FakeUrbg<uint32_t, 1, 0xffffffff>>()), 0xffffffff);
EXPECT_EQ((RangeSize<FakeUrbg<uint32_t, 1, 0xfffffffe>>()), 0xfffffffe);
EXPECT_EQ((RangeSize<FakeUrbg<uint32_t, 2, 0xfffffffe>>()), 0xfffffffd);
EXPECT_EQ((RangeSize<
FakeUrbg<uint32_t, 0, std::numeric_limits<uint32_t>::max()>>()),
0);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 0, 3>>()), 4);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 2, 2>>()), 1);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 2, 5>>()), 4);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 2, 6>>()), 5);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 1000, 1017>>()), 18);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 0, 0xffffffff>>()), 0x100000000ull);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 1, 0xffffffff>>()), 0xffffffffull);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 1, 0xfffffffe>>()), 0xfffffffeull);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 2, 0xfffffffe>>()), 0xfffffffdull);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 0, 0xffffffffffffffffull>>()), 0ull);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 1, 0xffffffffffffffffull>>()),
0xffffffffffffffffull);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 1, 0xfffffffffffffffeull>>()),
0xfffffffffffffffeull);
EXPECT_EQ((RangeSize<FakeUrbg<uint64_t, 2, 0xfffffffffffffffeull>>()),
0xfffffffffffffffdull);
EXPECT_EQ((RangeSize<
FakeUrbg<uint64_t, 0, std::numeric_limits<uint64_t>::max()>>()),
0);
}
TEST(FastUniformBitsTest, PowerOfTwoSubRangeSize) {
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint8_t, 0, 3>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint8_t, 2, 2>>()), 1);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint8_t, 2, 5>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint8_t, 2, 6>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint8_t, 2, 10>>()), 8);
EXPECT_EQ((PowerOfTwoSubRangeSize<
FakeUrbg<uint8_t, 0, std::numeric_limits<uint8_t>::max()>>()),
0);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint16_t, 0, 3>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint16_t, 2, 2>>()), 1);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint16_t, 2, 5>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint16_t, 2, 6>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint16_t, 1000, 1017>>()), 16);
EXPECT_EQ((PowerOfTwoSubRangeSize<
FakeUrbg<uint16_t, 0, std::numeric_limits<uint16_t>::max()>>()),
0);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint32_t, 0, 3>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint32_t, 2, 2>>()), 1);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint32_t, 2, 5>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint32_t, 2, 6>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint32_t, 1000, 1017>>()), 16);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint32_t, 0, 0xffffffff>>()), 0);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint32_t, 1, 0xffffffff>>()),
0x80000000);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint32_t, 1, 0xfffffffe>>()),
0x80000000);
EXPECT_EQ((PowerOfTwoSubRangeSize<
FakeUrbg<uint32_t, 0, std::numeric_limits<uint32_t>::max()>>()),
0);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 0, 3>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 2, 2>>()), 1);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 2, 5>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 2, 6>>()), 4);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 1000, 1017>>()), 16);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 0, 0xffffffff>>()),
0x100000000ull);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 1, 0xffffffff>>()),
0x80000000ull);
EXPECT_EQ((PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 1, 0xfffffffe>>()),
0x80000000ull);
EXPECT_EQ(
(PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 0, 0xffffffffffffffffull>>()),
0);
EXPECT_EQ(
(PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 1, 0xffffffffffffffffull>>()),
0x8000000000000000ull);
EXPECT_EQ(
(PowerOfTwoSubRangeSize<FakeUrbg<uint64_t, 1, 0xfffffffffffffffeull>>()),
0x8000000000000000ull);
EXPECT_EQ((PowerOfTwoSubRangeSize<
FakeUrbg<uint64_t, 0, std::numeric_limits<uint64_t>::max()>>()),
0);
}
TEST(FastUniformBitsTest, Urng4_VariousOutputs) {
// Tests that how values are composed; the single-bit deltas should be spread
// across each invocation.
Urng4bits urng4;
Urng31bits urng31;
Urng32bits urng32;
// 8-bit types
{
absl::random_internal::FastUniformBits<uint8_t> fast8;
FastUniformBits<uint8_t> fast8;
EXPECT_EQ(0x11, fast8(urng4));
EXPECT_EQ(0x2, fast8(urng31));
EXPECT_EQ(0x1, fast8(urng32));
}
// 16-bit types
{
absl::random_internal::FastUniformBits<uint16_t> fast16;
FastUniformBits<uint16_t> fast16;
EXPECT_EQ(0x1111, fast16(urng4));
EXPECT_EQ(0x1, fast16(urng32));
EXPECT_EQ(0xf02, fast16(urng31));
EXPECT_EQ(0xf01, fast16(urng32));
}
// 32-bit types
{
absl::random_internal::FastUniformBits<uint32_t> fast32;
FastUniformBits<uint32_t> fast32;
EXPECT_EQ(0x11111111, fast32(urng4));
EXPECT_EQ(0x1, fast32(urng32));
EXPECT_EQ(0x0f020f02, fast32(urng31));
EXPECT_EQ(0x74010f01, fast32(urng32));
}
// 64-bit types
{
absl::random_internal::FastUniformBits<uint64_t> fast64;
FastUniformBits<uint64_t> fast64;
EXPECT_EQ(0x1111111111111111, fast64(urng4));
EXPECT_EQ(0x0000000100000001, fast64(urng32));
EXPECT_EQ(0x387811c3c0870f02, fast64(urng31));
EXPECT_EQ(0x74010f0174010f01, fast64(urng32));
}
}
TEST(FastUniformBitsTest, URBG32bitRegression) {
// Validate with deterministic 32-bit std::minstd_rand
// to ensure that operator() performs as expected.
std::minstd_rand gen(1);
FastUniformBits<uint64_t> fast64;
EXPECT_EQ(0x05e47095f847c122ull, fast64(gen));
EXPECT_EQ(0x8f82c1ba30b64d22ull, fast64(gen));
EXPECT_EQ(0x3b971a3558155039ull, fast64(gen));
}
} // namespace
} // namespace random_internal
} // namespace absl

3
absl/strings/str_join.h
View file

@ -275,7 +275,8 @@ std::string StrJoin(const Range& range, absl::string_view separator) {
}
template <typename T>
std::string StrJoin(std::initializer_list<T> il, absl::string_view separator) {
std::string StrJoin(std::initializer_list<T> il,
absl::string_view separator) {
return strings_internal::JoinRange(il, separator);
}

3
absl/synchronization/internal/create_thread_identity.cc
View file

@ -31,7 +31,8 @@ namespace synchronization_internal {
// ThreadIdentity storage is persistent, we maintain a free-list of previously
// released ThreadIdentity objects.
static base_internal::SpinLock freelist_lock(base_internal::kLinkerInitialized);
static base_internal::SpinLock freelist_lock(
base_internal::kLinkerInitialized);
static base_internal::ThreadIdentity* thread_identity_freelist;
// A per-thread destructor for reclaiming associated ThreadIdentity objects.

5
absl/time/time.h
View file

@ -179,6 +179,7 @@ class Duration {
Duration& operator%=(Duration rhs);
// Overloads that forward to either the int64_t or double overloads above.
// Integer operands must be representable as int64_t.
template <typename T>
Duration& operator*=(T r) {
int64_t x = r;
@ -221,6 +222,7 @@ inline Duration operator+(Duration lhs, Duration rhs) { return lhs += rhs; }
inline Duration operator-(Duration lhs, Duration rhs) { return lhs -= rhs; }
// Multiplicative Operators
// Integer operands must be representable as int64_t.
template <typename T>
Duration operator*(Duration lhs, T rhs) {
return lhs *= rhs;
@ -375,7 +377,8 @@ constexpr Duration InfiniteDuration();
// Hours()
//
// Factory functions for constructing `Duration` values from an integral number
// of the unit indicated by the factory function's name.
// of the unit indicated by the factory function's name. The number must be
// representable as int64_t.
//
// Note: no "Days()" factory function exists because "a day" is ambiguous.
// Civil days are not always 24 hours long, and a 24-hour duration often does

8
ci/linux_clang-latest_libcxx_asan_bazel.sh
View file

@ -67,13 +67,21 @@ for std in ${STD}; do
--compilation_mode=${compilation_mode} \
--copt="-DDYNAMIC_ANNOTATIONS_ENABLED=1" \
--copt="-DADDRESS_SANITIZER" \
--copt="-DUNDEFINED_BEHAVIOR_SANITIZER" \
--copt="-fsanitize=address" \
--copt="-fsanitize=float-divide-by-zero" \
--copt="-fsanitize=nullability" \
--copt="-fsanitize=undefined" \
--copt="-fno-sanitize=vptr" \
--copt=-Werror \
--keep_going \
--linkopt="-fsanitize=address" \
--linkopt="-fsanitize-link-c++-runtime" \
--show_timestamps \
--test_env="ASAN_SYMBOLIZER_PATH=/opt/llvm/clang/bin/llvm-symbolizer" \
--test_env="TZDIR=/abseil-cpp/absl/time/internal/cctz/testdata/zoneinfo" \
--test_env="UBSAN_OPTIONS=print_stacktrace=1" \
--test_env="UBSAN_SYMBOLIZER_PATH=/opt/llvm/clang/bin/llvm-symbolizer" \
--test_output=errors \
--test_tag_filters="-benchmark,-noasan" \
${BAZEL_EXTRA_ARGS:-}