1 // Copyright 2004 The RE2 Authors. All Rights Reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 #include "re2/stringpiece.h" 6 #include "util/util.h" 7 8 using re2::StringPiece; 9 10 std::ostream& operator<<(std::ostream& o, const StringPiece& piece) { 11 o.write(piece.data(), piece.size()); 12 return o; 13 } 14 15 bool StringPiece::_equal(const StringPiece& x, const StringPiece& y) { 16 int len = x.size(); 17 if (len != y.size()) { 18 return false; 19 } 20 const char* p = x.data(); 21 const char* p2 = y.data(); 22 // Test last byte in case strings share large common prefix 23 if ((len > 0) && (p[len-1] != p2[len-1])) return false; 24 const char* p_limit = p + len; 25 for (; p < p_limit; p++, p2++) { 26 if (*p != *p2) 27 return false; 28 } 29 return true; 30 } 31 32 void StringPiece::CopyToString(string* target) const { 33 target->assign(ptr_, length_); 34 } 35 36 int StringPiece::copy(char* buf, size_type n, size_type pos) const { 37 int ret = min(length_ - pos, n); 38 memcpy(buf, ptr_ + pos, ret); 39 return ret; 40 } 41 42 int StringPiece::find(const StringPiece& s, size_type pos) const { 43 if (length_ < 0 || pos > static_cast<size_type>(length_)) 44 return npos; 45 46 const char* result = std::search(ptr_ + pos, ptr_ + length_, 47 s.ptr_, s.ptr_ + s.length_); 48 const size_type xpos = result - ptr_; 49 return xpos + s.length_ <= length_ ? xpos : npos; 50 } 51 52 int StringPiece::find(char c, size_type pos) const { 53 if (length_ <= 0 || pos >= static_cast<size_type>(length_)) { 54 return npos; 55 } 56 const char* result = std::find(ptr_ + pos, ptr_ + length_, c); 57 return result != ptr_ + length_ ? result - ptr_ : npos; 58 } 59 60 int StringPiece::rfind(const StringPiece& s, size_type pos) const { 61 if (length_ < s.length_) return npos; 62 const size_t ulen = length_; 63 if (s.length_ == 0) return min(ulen, pos); 64 65 const char* last = ptr_ + min(ulen - s.length_, pos) + s.length_; 66 const char* result = std::find_end(ptr_, last, s.ptr_, s.ptr_ + s.length_); 67 return result != last ? result - ptr_ : npos; 68 } 69 70 int StringPiece::rfind(char c, size_type pos) const { 71 if (length_ <= 0) return npos; 72 for (int i = min(pos, static_cast<size_type>(length_ - 1)); 73 i >= 0; --i) { 74 if (ptr_[i] == c) { 75 return i; 76 } 77 } 78 return npos; 79 } 80 81 StringPiece StringPiece::substr(size_type pos, size_type n) const { 82 if (pos > length_) pos = length_; 83 if (n > length_ - pos) n = length_ - pos; 84 return StringPiece(ptr_ + pos, n); 85 } 86 87 const StringPiece::size_type StringPiece::npos = size_type(-1); 88
