| Index: base/macros.h
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| diff --git a/base/macros.h b/base/macros.h
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| deleted file mode 100644
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| index 53b3926cd2424ac355304f1110e0150696aec4ce..0000000000000000000000000000000000000000
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| --- a/base/macros.h
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| +++ /dev/null
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| @@ -1,198 +0,0 @@
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| -// Copyright 2014 The Chromium Authors. All rights reserved.
|
| -// Use of this source code is governed by a BSD-style license that can be
|
| -// found in the LICENSE file.
|
| -
|
| -// This file contains macros and macro-like constructs (e.g., templates) that
|
| -// are commonly used throughout Chromium source. (It may also contain things
|
| -// that are closely related to things that are commonly used that belong in this
|
| -// file.)
|
| -
|
| -#ifndef BASE_MACROS_H_
|
| -#define BASE_MACROS_H_
|
| -
|
| -#include <stddef.h> // For size_t.
|
| -#include <string.h> // For memcpy.
|
| -
|
| -// Put this in the declarations for a class to be uncopyable.
|
| -#define DISALLOW_COPY(TypeName) \
|
| - TypeName(const TypeName&) = delete
|
| -
|
| -// Put this in the declarations for a class to be unassignable.
|
| -#define DISALLOW_ASSIGN(TypeName) \
|
| - void operator=(const TypeName&) = delete
|
| -
|
| -// A macro to disallow the copy constructor and operator= functions
|
| -// This should be used in the private: declarations for a class
|
| -#define DISALLOW_COPY_AND_ASSIGN(TypeName) \
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| - TypeName(const TypeName&); \
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| - void operator=(const TypeName&)
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| -
|
| -// An older, deprecated, politically incorrect name for the above.
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| -// NOTE: The usage of this macro was banned from our code base, but some
|
| -// third_party libraries are yet using it.
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| -// TODO(tfarina): Figure out how to fix the usage of this macro in the
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| -// third_party libraries and get rid of it.
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| -#define DISALLOW_EVIL_CONSTRUCTORS(TypeName) DISALLOW_COPY_AND_ASSIGN(TypeName)
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| -
|
| -// A macro to disallow all the implicit constructors, namely the
|
| -// default constructor, copy constructor and operator= functions.
|
| -//
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| -// This should be used in the private: declarations for a class
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| -// that wants to prevent anyone from instantiating it. This is
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| -// especially useful for classes containing only static methods.
|
| -#define DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \
|
| - TypeName() = delete; \
|
| - DISALLOW_COPY_AND_ASSIGN(TypeName)
|
| -
|
| -// The arraysize(arr) macro returns the # of elements in an array arr.
|
| -// The expression is a compile-time constant, and therefore can be
|
| -// used in defining new arrays, for example. If you use arraysize on
|
| -// a pointer by mistake, you will get a compile-time error.
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| -
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| -// This template function declaration is used in defining arraysize.
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| -// Note that the function doesn't need an implementation, as we only
|
| -// use its type.
|
| -template <typename T, size_t N> char (&ArraySizeHelper(T (&array)[N]))[N];
|
| -#define arraysize(array) (sizeof(ArraySizeHelper(array)))
|
| -
|
| -
|
| -// Use implicit_cast as a safe version of static_cast or const_cast
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| -// for upcasting in the type hierarchy (i.e. casting a pointer to Foo
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| -// to a pointer to SuperclassOfFoo or casting a pointer to Foo to
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| -// a const pointer to Foo).
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| -// When you use implicit_cast, the compiler checks that the cast is safe.
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| -// Such explicit implicit_casts are necessary in surprisingly many
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| -// situations where C++ demands an exact type match instead of an
|
| -// argument type convertible to a target type.
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| -//
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| -// The From type can be inferred, so the preferred syntax for using
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| -// implicit_cast is the same as for static_cast etc.:
|
| -//
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| -// implicit_cast<ToType>(expr)
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| -//
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| -// implicit_cast would have been part of the C++ standard library,
|
| -// but the proposal was submitted too late. It will probably make
|
| -// its way into the language in the future.
|
| -template<typename To, typename From>
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| -inline To implicit_cast(From const &f) {
|
| - return f;
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| -}
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| -
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| -// The COMPILE_ASSERT macro can be used to verify that a compile time
|
| -// expression is true. For example, you could use it to verify the
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| -// size of a static array:
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| -//
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| -// COMPILE_ASSERT(arraysize(content_type_names) == CONTENT_NUM_TYPES,
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| -// content_type_names_incorrect_size);
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| -//
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| -// or to make sure a struct is smaller than a certain size:
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| -//
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| -// COMPILE_ASSERT(sizeof(foo) < 128, foo_too_large);
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| -//
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| -// The second argument to the macro is the name of the variable. If
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| -// the expression is false, most compilers will issue a warning/error
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| -// containing the name of the variable.
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| -
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| -#undef COMPILE_ASSERT
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| -#define COMPILE_ASSERT(expr, msg) static_assert(expr, #msg)
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| -
|
| -// bit_cast<Dest,Source> is a template function that implements the
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| -// equivalent of "*reinterpret_cast<Dest*>(&source)". We need this in
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| -// very low-level functions like the protobuf library and fast math
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| -// support.
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| -//
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| -// float f = 3.14159265358979;
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| -// int i = bit_cast<int32>(f);
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| -// // i = 0x40490fdb
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| -//
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| -// The classical address-casting method is:
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| -//
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| -// // WRONG
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| -// float f = 3.14159265358979; // WRONG
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| -// int i = * reinterpret_cast<int*>(&f); // WRONG
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| -//
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| -// The address-casting method actually produces undefined behavior
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| -// according to ISO C++ specification section 3.10 -15 -. Roughly, this
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| -// section says: if an object in memory has one type, and a program
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| -// accesses it with a different type, then the result is undefined
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| -// behavior for most values of "different type".
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| -//
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| -// This is true for any cast syntax, either *(int*)&f or
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| -// *reinterpret_cast<int*>(&f). And it is particularly true for
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| -// conversions between integral lvalues and floating-point lvalues.
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| -//
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| -// The purpose of 3.10 -15- is to allow optimizing compilers to assume
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| -// that expressions with different types refer to different memory. gcc
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| -// 4.0.1 has an optimizer that takes advantage of this. So a
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| -// non-conforming program quietly produces wildly incorrect output.
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| -//
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| -// The problem is not the use of reinterpret_cast. The problem is type
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| -// punning: holding an object in memory of one type and reading its bits
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| -// back using a different type.
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| -//
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| -// The C++ standard is more subtle and complex than this, but that
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| -// is the basic idea.
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| -//
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| -// Anyways ...
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| -//
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| -// bit_cast<> calls memcpy() which is blessed by the standard,
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| -// especially by the example in section 3.9 . Also, of course,
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| -// bit_cast<> wraps up the nasty logic in one place.
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| -//
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| -// Fortunately memcpy() is very fast. In optimized mode, with a
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| -// constant size, gcc 2.95.3, gcc 4.0.1, and msvc 7.1 produce inline
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| -// code with the minimal amount of data movement. On a 32-bit system,
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| -// memcpy(d,s,4) compiles to one load and one store, and memcpy(d,s,8)
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| -// compiles to two loads and two stores.
|
| -//
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| -// I tested this code with gcc 2.95.3, gcc 4.0.1, icc 8.1, and msvc 7.1.
|
| -//
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| -// WARNING: if Dest or Source is a non-POD type, the result of the memcpy
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| -// is likely to surprise you.
|
| -
|
| -template <class Dest, class Source>
|
| -inline Dest bit_cast(const Source& source) {
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| - COMPILE_ASSERT(sizeof(Dest) == sizeof(Source), VerifySizesAreEqual);
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| -
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| - Dest dest;
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| - memcpy(&dest, &source, sizeof(dest));
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| - return dest;
|
| -}
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| -
|
| -// Used to explicitly mark the return value of a function as unused. If you are
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| -// really sure you don't want to do anything with the return value of a function
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| -// that has been marked WARN_UNUSED_RESULT, wrap it with this. Example:
|
| -//
|
| -// scoped_ptr<MyType> my_var = ...;
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| -// if (TakeOwnership(my_var.get()) == SUCCESS)
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| -// ignore_result(my_var.release());
|
| -//
|
| -template<typename T>
|
| -inline void ignore_result(const T&) {
|
| -}
|
| -
|
| -// The following enum should be used only as a constructor argument to indicate
|
| -// that the variable has static storage class, and that the constructor should
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| -// do nothing to its state. It indicates to the reader that it is legal to
|
| -// declare a static instance of the class, provided the constructor is given
|
| -// the base::LINKER_INITIALIZED argument. Normally, it is unsafe to declare a
|
| -// static variable that has a constructor or a destructor because invocation
|
| -// order is undefined. However, IF the type can be initialized by filling with
|
| -// zeroes (which the loader does for static variables), AND the destructor also
|
| -// does nothing to the storage, AND there are no virtual methods, then a
|
| -// constructor declared as
|
| -// explicit MyClass(base::LinkerInitialized x) {}
|
| -// and invoked as
|
| -// static MyClass my_variable_name(base::LINKER_INITIALIZED);
|
| -namespace base {
|
| -enum LinkerInitialized { LINKER_INITIALIZED };
|
| -
|
| -// Use these to declare and define a static local variable (static T;) so that
|
| -// it is leaked so that its destructors are not called at exit. If you need
|
| -// thread-safe initialization, use base/lazy_instance.h instead.
|
| -#define CR_DEFINE_STATIC_LOCAL(type, name, arguments) \
|
| - static type& name = *new type arguments
|
| -
|
| -} // base
|
| -
|
| -#endif // BASE_MACROS_H_
|
|
|