has_bits.h 3.3 KB

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  1. // Protocol Buffers - Google's data interchange format
  2. // Copyright 2008 Google Inc. All rights reserved.
  3. // https://developers.google.com/protocol-buffers/
  4. //
  5. // Redistribution and use in source and binary forms, with or without
  6. // modification, are permitted provided that the following conditions are
  7. // met:
  8. //
  9. // * Redistributions of source code must retain the above copyright
  10. // notice, this list of conditions and the following disclaimer.
  11. // * Redistributions in binary form must reproduce the above
  12. // copyright notice, this list of conditions and the following disclaimer
  13. // in the documentation and/or other materials provided with the
  14. // distribution.
  15. // * Neither the name of Google Inc. nor the names of its
  16. // contributors may be used to endorse or promote products derived from
  17. // this software without specific prior written permission.
  18. //
  19. // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20. // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21. // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22. // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  23. // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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  25. // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26. // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27. // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28. // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29. // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30. #ifndef GOOGLE_PROTOBUF_HAS_BITS_H__
  31. #define GOOGLE_PROTOBUF_HAS_BITS_H__
  32. #include <google/protobuf/stubs/common.h>
  33. #include <google/protobuf/stubs/port.h>
  34. namespace google {
  35. namespace protobuf {
  36. namespace internal {
  37. template<size_t doublewords>
  38. class HasBits {
  39. public:
  40. HasBits() GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE { Clear(); }
  41. void Clear() GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE {
  42. memset(has_bits_, 0, sizeof(has_bits_));
  43. }
  44. ::google::protobuf::uint32& operator[](int index) GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE {
  45. return has_bits_[index];
  46. }
  47. const ::google::protobuf::uint32& operator[](int index) const
  48. GOOGLE_PROTOBUF_ATTRIBUTE_ALWAYS_INLINE {
  49. return has_bits_[index];
  50. }
  51. bool operator==(const HasBits<doublewords>& rhs) const {
  52. return memcmp(has_bits_, rhs.has_bits_, sizeof(has_bits_)) == 0;
  53. }
  54. bool operator!=(const HasBits<doublewords>& rhs) const {
  55. return !(*this == rhs);
  56. }
  57. bool empty() const;
  58. private:
  59. ::google::protobuf::uint32 has_bits_[doublewords];
  60. };
  61. template <>
  62. inline bool HasBits<1>::empty() const {
  63. return !has_bits_[0];
  64. }
  65. template <>
  66. inline bool HasBits<2>::empty() const {
  67. return !(has_bits_[0] | has_bits_[1]);
  68. }
  69. template <>
  70. inline bool HasBits<3>::empty() const {
  71. return !(has_bits_[0] | has_bits_[1] | has_bits_[2]);
  72. }
  73. template <>
  74. inline bool HasBits<4>::empty() const {
  75. return !(has_bits_[0] | has_bits_[1] | has_bits_[2] | has_bits_[3]);
  76. }
  77. template <size_t doublewords>
  78. inline bool HasBits<doublewords>::empty() const {
  79. for (size_t i = 0; i < doublewords; ++i) {
  80. if (has_bits_[i]) return false;
  81. }
  82. return true;
  83. }
  84. } // namespace internal
  85. } // namespace protobuf
  86. } // namespace google
  87. #endif // GOOGLE_PROTOBUF_HAS_BITS_H__