Replace RE2 import with a dependency

third_party/re2/re2/stringpiece.cc

-// Copyright 2004 The RE2 Authors.  All Rights Reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-#include "re2/stringpiece.h"
-#include "util/util.h"
-
-using re2::StringPiece;
-
-std::ostream& operator<<(std::ostream& o, const StringPiece& piece) {
-  o.write(piece.data(), piece.size());
-  return o;
-}
-
-bool StringPiece::_equal(const StringPiece& x, const StringPiece& y) {
-  int len = x.size();
-  if (len != y.size()) {
-    return false;
-  }
-  const char* p = x.data();
-  const char* p2 = y.data();
-  // Test last byte in case strings share large common prefix
-  if ((len > 0) && (p[len-1] != p2[len-1])) return false;
-  const char* p_limit = p + len;
-  for (; p < p_limit; p++, p2++) {
-    if (*p != *p2)
-      return false;
-  }
-  return true;
-}
-
-void StringPiece::CopyToString(string* target) const {
-  target->assign(ptr_, length_);
-}
-
-void StringPiece::AppendToString(string* target) const {
-  target->append(ptr_, length_);
-}
-
-StringPiece::size_type StringPiece::copy(char* buf, size_type n,
-                                         size_type pos) const {
-  size_type ret = min(length_ - pos, n);
-  memcpy(buf, ptr_ + pos, ret);
-  return ret;
-}
-
-bool StringPiece::contains(StringPiece s) const {
-  return find(s, 0) != npos;
-}
-
-StringPiece::size_type StringPiece::find(const StringPiece& s,
-                                         size_type pos) const {
-  if (length_ < 0 || pos > static_cast<size_type>(length_))
-    return npos;
-
-  const char* result = std::search(ptr_ + pos, ptr_ + length_,
-                                   s.ptr_, s.ptr_ + s.length_);
-  const size_type xpos = result - ptr_;
-  return xpos + s.length_ <= static_cast<size_type>(length_) ? xpos : npos;
-}
-
-StringPiece::size_type StringPiece::find(char c, size_type pos) const {
-  if (length_ <= 0 || pos >= static_cast<size_type>(length_)) {
-    return npos;
-  }
-  const char* result = std::find(ptr_ + pos, ptr_ + length_, c);
-  return result != ptr_ + length_ ? result - ptr_ : npos;
-}
-
-StringPiece::size_type StringPiece::rfind(const StringPiece& s,
-                                          size_type pos) const {
-  if (length_ < s.length_) return npos;
-  const size_type ulen = length_;
-  if (s.length_ == 0) return min(ulen, pos);
-
-  const char* last = ptr_ + min(ulen - s.length_, pos) + s.length_;
-  const char* result = std::find_end(ptr_, last, s.ptr_, s.ptr_ + s.length_);
-  return result != last ? result - ptr_ : npos;
-}
-
-StringPiece::size_type StringPiece::rfind(char c, size_type pos) const {
-  if (length_ <= 0) return npos;
-  for (int i = static_cast<int>(min(pos, static_cast<size_type>(length_ - 1)));
-       i >= 0; --i) {
-    if (ptr_[i] == c) {
-      return i;
-    }
-  }
-  return npos;
-}
-
-StringPiece StringPiece::substr(size_type pos, size_type n) const {
-  if (pos > static_cast<size_type>(length_)) pos = static_cast<size_type>(length_);
-  if (n > length_ - pos) n = length_ - pos;
-  return StringPiece(ptr_ + pos, static_cast<int>(n));
-}
-
-const StringPiece::size_type StringPiece::npos = size_type(-1);