| 1 | // Protocol Buffers - Google's data interchange format |
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| 2 | // Copyright 2008 Google Inc. All rights reserved. |
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| 3 | // https://developers.google.com/protocol-buffers/ |
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| 4 | // |
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| 5 | // Redistribution and use in source and binary forms, with or without |
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| 6 | // modification, are permitted provided that the following conditions are |
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| 7 | // met: |
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| 8 | // |
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| 9 | // * Redistributions of source code must retain the above copyright |
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| 10 | // notice, this list of conditions and the following disclaimer. |
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| 11 | // * Redistributions in binary form must reproduce the above |
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| 12 | // copyright notice, this list of conditions and the following disclaimer |
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| 13 | // in the documentation and/or other materials provided with the |
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| 14 | // distribution. |
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| 15 | // * Neither the name of Google Inc. nor the names of its |
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| 16 | // contributors may be used to endorse or promote products derived from |
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| 17 | // this software without specific prior written permission. |
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| 18 | // |
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| 19 | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
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| 20 | // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
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| 21 | // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
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| 22 | // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
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| 23 | // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
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| 24 | // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
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| 25 | // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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| 26 | // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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| 27 | // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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| 28 | // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
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| 29 | // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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| 30 | |
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| 31 | #ifndef GOOGLE_PROTOBUF_MACROS_H__ |
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| 32 | #define GOOGLE_PROTOBUF_MACROS_H__ |
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| 33 | |
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| 34 | #include <google/protobuf/stubs/port.h> |
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| 35 | |
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| 36 | namespace google { |
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| 37 | namespace protobuf { |
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| 38 | |
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| 39 | #undef GOOGLE_DISALLOW_EVIL_CONSTRUCTORS |
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| 40 | #define GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(TypeName) \ |
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| 41 | TypeName(const TypeName&); \ |
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| 42 | void operator=(const TypeName&) |
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| 43 | |
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| 44 | #undef GOOGLE_DISALLOW_IMPLICIT_CONSTRUCTORS |
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| 45 | #define GOOGLE_DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \ |
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| 46 | TypeName(); \ |
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| 47 | TypeName(const TypeName&); \ |
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| 48 | void operator=(const TypeName&) |
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| 49 | |
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| 50 | // =================================================================== |
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| 51 | // from google3/base/basictypes.h |
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| 52 | |
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| 53 | // The GOOGLE_ARRAYSIZE(arr) macro returns the # of elements in an array arr. |
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| 54 | // The expression is a compile-time constant, and therefore can be |
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| 55 | // used in defining new arrays, for example. |
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| 56 | // |
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| 57 | // GOOGLE_ARRAYSIZE catches a few type errors. If you see a compiler error |
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| 58 | // |
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| 59 | // "warning: division by zero in ..." |
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| 60 | // |
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| 61 | // when using GOOGLE_ARRAYSIZE, you are (wrongfully) giving it a pointer. |
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| 62 | // You should only use GOOGLE_ARRAYSIZE on statically allocated arrays. |
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| 63 | // |
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| 64 | // The following comments are on the implementation details, and can |
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| 65 | // be ignored by the users. |
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| 66 | // |
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| 67 | // ARRAYSIZE(arr) works by inspecting sizeof(arr) (the # of bytes in |
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| 68 | // the array) and sizeof(*(arr)) (the # of bytes in one array |
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| 69 | // element). If the former is divisible by the latter, perhaps arr is |
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| 70 | // indeed an array, in which case the division result is the # of |
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| 71 | // elements in the array. Otherwise, arr cannot possibly be an array, |
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| 72 | // and we generate a compiler error to prevent the code from |
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| 73 | // compiling. |
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| 74 | // |
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| 75 | // Since the size of bool is implementation-defined, we need to cast |
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| 76 | // !(sizeof(a) & sizeof(*(a))) to size_t in order to ensure the final |
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| 77 | // result has type size_t. |
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| 78 | // |
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| 79 | // This macro is not perfect as it wrongfully accepts certain |
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| 80 | // pointers, namely where the pointer size is divisible by the pointee |
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| 81 | // size. Since all our code has to go through a 32-bit compiler, |
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| 82 | // where a pointer is 4 bytes, this means all pointers to a type whose |
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| 83 | // size is 3 or greater than 4 will be (righteously) rejected. |
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| 84 | // |
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| 85 | // Kudos to Jorg Brown for this simple and elegant implementation. |
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| 86 | |
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| 87 | #undef GOOGLE_ARRAYSIZE |
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| 88 | #define GOOGLE_ARRAYSIZE(a) \ |
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| 89 | ((sizeof(a) / sizeof(*(a))) / \ |
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| 90 | static_cast<size_t>(!(sizeof(a) % sizeof(*(a))))) |
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| 91 | |
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| 92 | // The COMPILE_ASSERT macro can be used to verify that a compile time |
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| 93 | // expression is true. For example, you could use it to verify the |
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| 94 | // size of a static array: |
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| 95 | // |
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| 96 | // COMPILE_ASSERT(ARRAYSIZE(content_type_names) == CONTENT_NUM_TYPES, |
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| 97 | // content_type_names_incorrect_size); |
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| 98 | // |
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| 99 | // or to make sure a struct is smaller than a certain size: |
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| 100 | // |
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| 101 | // COMPILE_ASSERT(sizeof(foo) < 128, foo_too_large); |
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| 102 | // |
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| 103 | // The second argument to the macro is the name of the variable. If |
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| 104 | // the expression is false, most compilers will issue a warning/error |
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| 105 | // containing the name of the variable. |
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| 106 | |
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| 107 | namespace internal { |
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| 108 | |
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| 109 | template <bool> |
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| 110 | struct CompileAssert { |
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| 111 | }; |
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| 112 | |
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| 113 | } // namespace internal |
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| 114 | |
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| 115 | #define GOOGLE_COMPILE_ASSERT(expr, msg) static_assert(expr, #msg) |
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| 116 | |
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| 117 | } // namespace protobuf |
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| 118 | } // namespace google |
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| 119 | |
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| 120 | #endif // GOOGLE_PROTOBUF_MACROS_H__ |
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| 121 | |
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