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-rw-r--r--base/string_piece.cc214
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diff --git a/base/string_piece.cc b/base/string_piece.cc
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+++ b/base/string_piece.cc
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+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+// Copied from strings/stringpiece.cc with modifications
+
+#include <algorithm>
+#include <ostream>
+
+#include "base/string_piece.h"
+
+namespace base {
+
+typedef StringPiece::size_type size_type;
+
+bool operator==(const StringPiece& x, const StringPiece& y) {
+ if (x.size() != y.size())
+ return false;
+
+ return StringPiece::wordmemcmp(x.data(), y.data(), x.size()) == 0;
+}
+
+void StringPiece::CopyToString(std::string* target) const {
+ target->assign(!empty() ? data() : "", size());
+}
+
+void StringPiece::AppendToString(std::string* target) const {
+ if (!empty())
+ target->append(data(), size());
+}
+
+size_type StringPiece::copy(char* buf, size_type n, size_type pos) const {
+ size_type ret = std::min(length_ - pos, n);
+ memcpy(buf, ptr_ + pos, ret);
+ return ret;
+}
+
+size_type StringPiece::find(const StringPiece& s, size_type pos) const {
+ if (pos > 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_ <= length_ ? xpos : npos;
+}
+
+size_type StringPiece::find(char c, size_type pos) const {
+ if (pos >= length_)
+ return npos;
+
+ const char* result = std::find(ptr_ + pos, ptr_ + length_, c);
+ return result != ptr_ + length_ ? static_cast<size_t>(result - ptr_) : npos;
+}
+
+size_type StringPiece::rfind(const StringPiece& s, size_type pos) const {
+ if (length_ < s.length_)
+ return npos;
+
+ if (s.empty())
+ return std::min(length_, pos);
+
+ const char* last = ptr_ + std::min(length_ - s.length_, pos) + s.length_;
+ const char* result = std::find_end(ptr_, last, s.ptr_, s.ptr_ + s.length_);
+ return result != last ? static_cast<size_t>(result - ptr_) : npos;
+}
+
+size_type StringPiece::rfind(char c, size_type pos) const {
+ if (length_ == 0)
+ return npos;
+
+ for (size_type i = std::min(pos, length_ - 1); ; --i) {
+ if (ptr_[i] == c)
+ return i;
+ if (i == 0)
+ break;
+ }
+ return npos;
+}
+
+// For each character in characters_wanted, sets the index corresponding
+// to the ASCII code of that character to 1 in table. This is used by
+// the find_.*_of methods below to tell whether or not a character is in
+// the lookup table in constant time.
+// The argument `table' must be an array that is large enough to hold all
+// the possible values of an unsigned char. Thus it should be be declared
+// as follows:
+// bool table[UCHAR_MAX + 1]
+static inline void BuildLookupTable(const StringPiece& characters_wanted,
+ bool* table) {
+ const size_type length = characters_wanted.length();
+ const char* const data = characters_wanted.data();
+ for (size_type i = 0; i < length; ++i) {
+ table[static_cast<unsigned char>(data[i])] = true;
+ }
+}
+
+size_type StringPiece::find_first_of(const StringPiece& s,
+ size_type pos) const {
+ if (length_ == 0 || s.length_ == 0)
+ return npos;
+
+ // Avoid the cost of BuildLookupTable() for a single-character search.
+ if (s.length_ == 1)
+ return find_first_of(s.ptr_[0], pos);
+
+ bool lookup[UCHAR_MAX + 1] = { false };
+ BuildLookupTable(s, lookup);
+ for (size_type i = pos; i < length_; ++i) {
+ if (lookup[static_cast<unsigned char>(ptr_[i])]) {
+ return i;
+ }
+ }
+ return npos;
+}
+
+size_type StringPiece::find_first_not_of(const StringPiece& s,
+ size_type pos) const {
+ if (length_ == 0)
+ return npos;
+
+ if (s.length_ == 0)
+ return 0;
+
+ // Avoid the cost of BuildLookupTable() for a single-character search.
+ if (s.length_ == 1)
+ return find_first_not_of(s.ptr_[0], pos);
+
+ bool lookup[UCHAR_MAX + 1] = { false };
+ BuildLookupTable(s, lookup);
+ for (size_type i = pos; i < length_; ++i) {
+ if (!lookup[static_cast<unsigned char>(ptr_[i])]) {
+ return i;
+ }
+ }
+ return npos;
+}
+
+size_type StringPiece::find_first_not_of(char c, size_type pos) const {
+ if (length_ == 0)
+ return npos;
+
+ for (; pos < length_; ++pos) {
+ if (ptr_[pos] != c) {
+ return pos;
+ }
+ }
+ return npos;
+}
+
+size_type StringPiece::find_last_of(const StringPiece& s, size_type pos) const {
+ if (length_ == 0 || s.length_ == 0)
+ return npos;
+
+ // Avoid the cost of BuildLookupTable() for a single-character search.
+ if (s.length_ == 1)
+ return find_last_of(s.ptr_[0], pos);
+
+ bool lookup[UCHAR_MAX + 1] = { false };
+ BuildLookupTable(s, lookup);
+ for (size_type i = std::min(pos, length_ - 1); ; --i) {
+ if (lookup[static_cast<unsigned char>(ptr_[i])])
+ return i;
+ if (i == 0)
+ break;
+ }
+ return npos;
+}
+
+size_type StringPiece::find_last_not_of(const StringPiece& s,
+ size_type pos) const {
+ if (length_ == 0)
+ return npos;
+
+ size_type i = std::min(pos, length_ - 1);
+ if (s.length_ == 0)
+ return i;
+
+ // Avoid the cost of BuildLookupTable() for a single-character search.
+ if (s.length_ == 1)
+ return find_last_not_of(s.ptr_[0], pos);
+
+ bool lookup[UCHAR_MAX + 1] = { false };
+ BuildLookupTable(s, lookup);
+ for (; ; --i) {
+ if (!lookup[static_cast<unsigned char>(ptr_[i])])
+ return i;
+ if (i == 0)
+ break;
+ }
+ return npos;
+}
+
+size_type StringPiece::find_last_not_of(char c, size_type pos) const {
+ if (length_ == 0)
+ return npos;
+
+ for (size_type i = std::min(pos, length_ - 1); ; --i) {
+ if (ptr_[i] != c)
+ return i;
+ if (i == 0)
+ break;
+ }
+ return npos;
+}
+
+StringPiece StringPiece::substr(size_type pos, size_type n) const {
+ if (pos > length_) pos = length_;
+ if (n > length_ - pos) n = length_ - pos;
+ return StringPiece(ptr_ + pos, n);
+}
+
+const StringPiece::size_type StringPiece::npos = size_type(-1);
+
+} // namespace base