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Diffstat (limited to 'third_party/protobuf/3.6.0/src/google/protobuf/stubs/macros.h')
| -rw-r--r-- | third_party/protobuf/3.6.0/src/google/protobuf/stubs/macros.h | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/third_party/protobuf/3.6.0/src/google/protobuf/stubs/macros.h b/third_party/protobuf/3.6.0/src/google/protobuf/stubs/macros.h new file mode 100644 index 0000000000..0e9a9ec198 --- /dev/null +++ b/third_party/protobuf/3.6.0/src/google/protobuf/stubs/macros.h @@ -0,0 +1,168 @@ +// Protocol Buffers - Google's data interchange format +// Copyright 2008 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef GOOGLE_PROTOBUF_MACROS_H__ +#define GOOGLE_PROTOBUF_MACROS_H__ + +#include <google/protobuf/stubs/port.h> + +namespace google { +namespace protobuf { + +#undef GOOGLE_DISALLOW_EVIL_CONSTRUCTORS +#define GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(TypeName) \ + TypeName(const TypeName&); \ + void operator=(const TypeName&) + +#undef GOOGLE_DISALLOW_IMPLICIT_CONSTRUCTORS +#define GOOGLE_DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \ + TypeName(); \ + TypeName(const TypeName&); \ + void operator=(const TypeName&) + +// =================================================================== +// from google3/base/basictypes.h + +// The GOOGLE_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. +// +// GOOGLE_ARRAYSIZE catches a few type errors. If you see a compiler error +// +// "warning: division by zero in ..." +// +// when using GOOGLE_ARRAYSIZE, you are (wrongfully) giving it a pointer. +// You should only use GOOGLE_ARRAYSIZE on statically allocated arrays. +// +// The following comments are on the implementation details, and can +// be ignored by the users. +// +// ARRAYSIZE(arr) works by inspecting sizeof(arr) (the # of bytes in +// the array) and sizeof(*(arr)) (the # of bytes in one array +// element). If the former is divisible by the latter, perhaps arr is +// indeed an array, in which case the division result is the # of +// elements in the array. Otherwise, arr cannot possibly be an array, +// and we generate a compiler error to prevent the code from +// compiling. +// +// Since the size of bool is implementation-defined, we need to cast +// !(sizeof(a) & sizeof(*(a))) to size_t in order to ensure the final +// result has type size_t. +// +// This macro is not perfect as it wrongfully accepts certain +// pointers, namely where the pointer size is divisible by the pointee +// size. Since all our code has to go through a 32-bit compiler, +// where a pointer is 4 bytes, this means all pointers to a type whose +// size is 3 or greater than 4 will be (righteously) rejected. +// +// Kudos to Jorg Brown for this simple and elegant implementation. + +#undef GOOGLE_ARRAYSIZE +#define GOOGLE_ARRAYSIZE(a) \ + ((sizeof(a) / sizeof(*(a))) / \ + static_cast<size_t>(!(sizeof(a) % sizeof(*(a))))) + +// 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 +// size of a static array: +// +// COMPILE_ASSERT(ARRAYSIZE(content_type_names) == CONTENT_NUM_TYPES, +// content_type_names_incorrect_size); +// +// or to make sure a struct is smaller than a certain size: +// +// COMPILE_ASSERT(sizeof(foo) < 128, foo_too_large); +// +// The second argument to the macro is the name of the variable. If +// the expression is false, most compilers will issue a warning/error +// containing the name of the variable. + +namespace internal { + +template <bool> +struct CompileAssert { +}; + +} // namespace internal + +#undef GOOGLE_COMPILE_ASSERT +#if __cplusplus >= 201103L +#define GOOGLE_COMPILE_ASSERT(expr, msg) static_assert(expr, #msg) +#else +#define GOOGLE_COMPILE_ASSERT(expr, msg) \ + ::google::protobuf::internal::CompileAssert<(bool(expr))> \ + msg[bool(expr) ? 1 : -1]; \ + (void)msg +// Implementation details of COMPILE_ASSERT: +// +// - COMPILE_ASSERT works by defining an array type that has -1 +// elements (and thus is invalid) when the expression is false. +// +// - The simpler definition +// +// #define COMPILE_ASSERT(expr, msg) typedef char msg[(expr) ? 1 : -1] +// +// does not work, as gcc supports variable-length arrays whose sizes +// are determined at run-time (this is gcc's extension and not part +// of the C++ standard). As a result, gcc fails to reject the +// following code with the simple definition: +// +// int foo; +// COMPILE_ASSERT(foo, msg); // not supposed to compile as foo is +// // not a compile-time constant. +// +// - By using the type CompileAssert<(bool(expr))>, we ensures that +// expr is a compile-time constant. (Template arguments must be +// determined at compile-time.) +// +// - The outter parentheses in CompileAssert<(bool(expr))> are necessary +// to work around a bug in gcc 3.4.4 and 4.0.1. If we had written +// +// CompileAssert<bool(expr)> +// +// instead, these compilers will refuse to compile +// +// COMPILE_ASSERT(5 > 0, some_message); +// +// (They seem to think the ">" in "5 > 0" marks the end of the +// template argument list.) +// +// - The array size is (bool(expr) ? 1 : -1), instead of simply +// +// ((expr) ? 1 : -1). +// +// This is to avoid running into a bug in MS VC 7.1, which +// causes ((0.0) ? 1 : -1) to incorrectly evaluate to 1. +#endif // __cplusplus >= 201103L + +} // namespace protobuf +} // namespace google + +#endif // GOOGLE_PROTOBUF_MACROS_H__ |