| // Copyright 2018 Google Inc. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #ifndef NINJA_HASHED_STR_VIEW_ |
| #define NINJA_HASHED_STR_VIEW_ |
| |
| #include <stdint.h> |
| |
| #include "string_piece.h" |
| |
| class HashedStr; |
| |
| using StrHashType = size_t; |
| |
| class HashedStrView { |
| public: |
| constexpr HashedStrView() {} |
| |
| HashedStrView(const char* str) : str_(str), hash_(HashStr(str_)) {} |
| HashedStrView(const std::string& str) : str_(str), hash_(HashStr(str_)) {} |
| HashedStrView(StringPiece str) : str_(str), hash_(HashStr(str_)) {} |
| inline HashedStrView(const HashedStr& str); |
| |
| // Bypass the hashing step when necessary for better performance. |
| explicit HashedStrView(const StringPiece& str, StrHashType hash) |
| : str_(str), hash_(hash) {} |
| |
| const StringPiece& str_view() const { return str_; } |
| |
| StrHashType hash() const { return hash_; } |
| const char* data() const { return str_.data(); } |
| size_t size() const { return str_.size(); } |
| bool empty() const { return str_.empty(); } |
| |
| private: |
| // Reversing the order of these fields would break the constructors, most of |
| // which initialize hash_ using str_. |
| StringPiece str_; |
| StrHashType hash_ = 0; |
| }; |
| |
| class HashedStr { |
| public: |
| HashedStr() {} |
| |
| HashedStr(const char* str) : str_(str), hash_(HashStr(str_)) {} |
| HashedStr(const std::string& str) : str_(str), hash_(HashStr(str_)) {} |
| HashedStr(std::string&& str) : str_(std::move(str)), hash_(HashStr(str_)) {} |
| explicit HashedStr(StringPiece str) : str_(NonNullData(str), str.size()), hash_(HashStr(str_)) {} |
| explicit HashedStr(const HashedStrView& str) : str_(NonNullData(str.str_view()), str.size()), hash_(str.hash()) {} |
| |
| HashedStr& operator=(std::string&& str) { |
| str_ = std::move(str); |
| hash_ = HashStr(str_); |
| return *this; |
| } |
| |
| HashedStr& operator=(const std::string& str) { |
| str_ = str; |
| hash_ = HashStr(str_); |
| return *this; |
| } |
| |
| HashedStr& operator=(StringPiece str) { |
| str_.assign(NonNullData(str), str.size()); |
| hash_ = HashStr(str_); |
| return *this; |
| } |
| |
| HashedStr& operator=(const HashedStrView& str) { |
| str_.assign(NonNullData(str.str_view()), str.size()); |
| hash_ = str.hash(); |
| return *this; |
| } |
| |
| const std::string& str() const { return str_; } |
| |
| StrHashType hash() const { return hash_; } |
| const char* c_str() const { return str_.c_str(); } |
| const char* data() const { return str_.data(); } |
| size_t size() const { return str_.size(); } |
| bool empty() const { return str_.empty(); } |
| |
| private: |
| static const char* NonNullData(const StringPiece& piece) { |
| return piece.data() == nullptr ? "" : piece.data(); |
| } |
| |
| // Reversing the order of these fields would break the constructors, most of |
| // which initialize hash_ using str_. |
| std::string str_; |
| StrHashType hash_ = 0; |
| }; |
| |
| inline HashedStrView::HashedStrView(const HashedStr& str) : str_(str.str()), hash_(str.hash()) {} |
| |
| inline bool operator==(const HashedStr& x, const HashedStr& y) { |
| return x.hash() == y.hash() && x.str() == y.str(); |
| } |
| |
| inline bool operator==(const HashedStr& x, const HashedStrView& y) { |
| return x.hash() == y.hash() && x.str() == y.str_view(); |
| } |
| |
| inline bool operator==(const HashedStrView& x, const HashedStr& y) { |
| return x.hash() == y.hash() && x.str_view() == y.str(); |
| } |
| |
| inline bool operator==(const HashedStrView& x, const HashedStrView& y) { |
| return x.hash() == y.hash() && x.str_view() == y.str_view(); |
| } |
| |
| inline bool operator!=(const HashedStr& x, const HashedStr& y) { return !(x == y); } |
| inline bool operator!=(const HashedStr& x, const HashedStrView& y) { return !(x == y); } |
| inline bool operator!=(const HashedStrView& x, const HashedStr& y) { return !(x == y); } |
| inline bool operator!=(const HashedStrView& x, const HashedStrView& y) { return !(x == y); } |
| |
| namespace std { |
| template<> struct hash<HashedStrView> { |
| size_t operator()(const HashedStrView& x) const { return x.hash(); } |
| }; |
| |
| template<> struct hash<HashedStr> { |
| size_t operator()(const HashedStr& x) const { return x.hash(); } |
| }; |
| } |
| |
| // The comparison operators ignore the hash code. For efficiency, the |
| // ConcurrentHashMap orders keys by their hash code first, then by their |
| // operator< functions. |
| |
| inline bool operator<(const HashedStr& x, const HashedStr& y) { return x.str() < y.str(); } |
| inline bool operator>(const HashedStr& x, const HashedStr& y) { return x.str() > y.str(); } |
| inline bool operator<=(const HashedStr& x, const HashedStr& y) { return x.str() <= y.str(); } |
| inline bool operator>=(const HashedStr& x, const HashedStr& y) { return x.str() >= y.str(); } |
| |
| inline bool operator<(const HashedStr& x, const HashedStrView& y) { return x.str() < y.str_view(); } |
| inline bool operator>(const HashedStr& x, const HashedStrView& y) { return x.str() > y.str_view(); } |
| inline bool operator<=(const HashedStr& x, const HashedStrView& y) { return x.str() <= y.str_view(); } |
| inline bool operator>=(const HashedStr& x, const HashedStrView& y) { return x.str() >= y.str_view(); } |
| |
| inline bool operator<(const HashedStrView& x, const HashedStr& y) { return x.str_view() < y.str(); } |
| inline bool operator>(const HashedStrView& x, const HashedStr& y) { return x.str_view() > y.str(); } |
| inline bool operator<=(const HashedStrView& x, const HashedStr& y) { return x.str_view() <= y.str(); } |
| inline bool operator>=(const HashedStrView& x, const HashedStr& y) { return x.str_view() >= y.str(); } |
| |
| inline bool operator<(const HashedStrView& x, const HashedStrView& y) { return x.str_view() < y.str_view(); } |
| inline bool operator>(const HashedStrView& x, const HashedStrView& y) { return x.str_view() > y.str_view(); } |
| inline bool operator<=(const HashedStrView& x, const HashedStrView& y) { return x.str_view() <= y.str_view(); } |
| inline bool operator>=(const HashedStrView& x, const HashedStrView& y) { return x.str_view() >= y.str_view(); } |
| |
| #endif // NINJA_HASHED_STR_VIEW_ |