1 // Copyright 2011 Google Inc. All Rights Reserved. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef NINJA_STRINGPIECE_H_ 16 #define NINJA_STRINGPIECE_H_ 17 18 #include <string> 19 20 #include <string.h> 21 22 /// StringPiece represents a slice of a string whose memory is managed 23 /// externally. It is useful for reducing the number of std::strings 24 /// we need to allocate. 25 struct StringPiece { 26 typedef const char* const_iterator; 27 StringPieceStringPiece28 StringPiece() : str_(NULL), len_(0) {} 29 30 /// The constructors intentionally allow for implicit conversions. StringPieceStringPiece31 StringPiece(const std::string& str) : str_(str.data()), len_(str.size()) {} StringPieceStringPiece32 StringPiece(const char* str) : str_(str), len_(strlen(str)) {} 33 StringPieceStringPiece34 StringPiece(const char* str, size_t len) : str_(str), len_(len) {} 35 36 bool operator==(const StringPiece& other) const { 37 return len_ == other.len_ && memcmp(str_, other.str_, len_) == 0; 38 } 39 40 bool operator!=(const StringPiece& other) const { 41 return !(*this == other); 42 } 43 44 /// Convert the slice into a full-fledged std::string, copying the 45 /// data into a new string. AsStringStringPiece46 std::string AsString() const { 47 return len_ ? std::string(str_, len_) : std::string(); 48 } 49 beginStringPiece50 const_iterator begin() const { 51 return str_; 52 } 53 endStringPiece54 const_iterator end() const { 55 return str_ + len_; 56 } 57 58 char operator[](size_t pos) const { 59 return str_[pos]; 60 } 61 sizeStringPiece62 size_t size() const { 63 return len_; 64 } 65 66 const char* str_; 67 size_t len_; 68 }; 69 70 #endif // NINJA_STRINGPIECE_H_ 71