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-rw-r--r--base/strings/string_piece.cc255
1 files changed, 255 insertions, 0 deletions
diff --git a/base/strings/string_piece.cc b/base/strings/string_piece.cc
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--- /dev/null
+++ b/base/strings/string_piece.cc
@@ -0,0 +1,255 @@
+// Copyright (c) 2012 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 "base/strings/string_piece.h"
+
+#include <algorithm>
+#include <ostream>
+
+namespace base {
+
+// MSVC doesn't like complex extern templates and DLLs.
+#if !defined(COMPILER_MSVC)
+namespace internal {
+template class StringPieceDetail<std::string>;
+template class StringPieceDetail<string16>;
+} // namespace internal
+
+template class BasicStringPiece<string16>;
+#endif
+
+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;
+}
+
+std::ostream& operator<<(std::ostream& o, const StringPiece& piece) {
+ o.write(piece.data(), static_cast<std::streamsize>(piece.size()));
+ return o;
+}
+
+namespace internal {
+void CopyToString(const StringPiece& self, std::string* target) {
+ target->assign(!self.empty() ? self.data() : "", self.size());
+}
+
+void AppendToString(const StringPiece& self, std::string* target) {
+ if (!self.empty())
+ target->append(self.data(), self.size());
+}
+
+StringPiece::size_type copy(const StringPiece& self,
+ char* buf,
+ StringPiece::size_type n,
+ StringPiece::size_type pos) {
+ StringPiece::size_type ret = std::min(self.size() - pos, n);
+ memcpy(buf, self.data() + pos, ret);
+ return ret;
+}
+
+StringPiece::size_type find(const StringPiece& self,
+ const StringPiece& s,
+ StringPiece::size_type pos) {
+ if (pos > self.size())
+ return StringPiece::npos;
+
+ StringPiece::const_iterator result =
+ std::search(self.begin() + pos, self.end(), s.begin(), s.end());
+ const StringPiece::size_type xpos =
+ static_cast<size_t>(result - self.begin());
+ return xpos + s.size() <= self.size() ? xpos : StringPiece::npos;
+}
+
+StringPiece::size_type find(const StringPiece& self,
+ char c,
+ StringPiece::size_type pos) {
+ if (pos >= self.size())
+ return StringPiece::npos;
+
+ StringPiece::const_iterator result =
+ std::find(self.begin() + pos, self.end(), c);
+ return result != self.end() ?
+ static_cast<size_t>(result - self.begin()) : StringPiece::npos;
+}
+
+StringPiece::size_type rfind(const StringPiece& self,
+ const StringPiece& s,
+ StringPiece::size_type pos) {
+ if (self.size() < s.size())
+ return StringPiece::npos;
+
+ if (s.empty())
+ return std::min(self.size(), pos);
+
+ StringPiece::const_iterator last =
+ self.begin() + std::min(self.size() - s.size(), pos) + s.size();
+ StringPiece::const_iterator result =
+ std::find_end(self.begin(), last, s.begin(), s.end());
+ return result != last ?
+ static_cast<size_t>(result - self.begin()) : StringPiece::npos;
+}
+
+StringPiece::size_type rfind(const StringPiece& self,
+ char c,
+ StringPiece::size_type pos) {
+ if (self.size() == 0)
+ return StringPiece::npos;
+
+ for (StringPiece::size_type i = std::min(pos, self.size() - 1); ; --i) {
+ if (self.data()[i] == c)
+ return i;
+ if (i == 0)
+ break;
+ }
+ return StringPiece::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 StringPiece::size_type length = characters_wanted.length();
+ const char* const data = characters_wanted.data();
+ for (StringPiece::size_type i = 0; i < length; ++i) {
+ table[static_cast<unsigned char>(data[i])] = true;
+ }
+}
+
+StringPiece::size_type find_first_of(const StringPiece& self,
+ const StringPiece& s,
+ StringPiece::size_type pos) {
+ if (self.size() == 0 || s.size() == 0)
+ return StringPiece::npos;
+
+ // Avoid the cost of BuildLookupTable() for a single-character search.
+ if (s.size() == 1)
+ return find(self, s.data()[0], pos);
+
+ bool lookup[UCHAR_MAX + 1] = { false };
+ BuildLookupTable(s, lookup);
+ for (StringPiece::size_type i = pos; i < self.size(); ++i) {
+ if (lookup[static_cast<unsigned char>(self.data()[i])]) {
+ return i;
+ }
+ }
+ return StringPiece::npos;
+}
+
+StringPiece::size_type find_first_not_of(const StringPiece& self,
+ const StringPiece& s,
+ StringPiece::size_type pos) {
+ if (self.size() == 0)
+ return StringPiece::npos;
+
+ if (s.size() == 0)
+ return 0;
+
+ // Avoid the cost of BuildLookupTable() for a single-character search.
+ if (s.size() == 1)
+ return find_first_not_of(self, s.data()[0], pos);
+
+ bool lookup[UCHAR_MAX + 1] = { false };
+ BuildLookupTable(s, lookup);
+ for (StringPiece::size_type i = pos; i < self.size(); ++i) {
+ if (!lookup[static_cast<unsigned char>(self.data()[i])]) {
+ return i;
+ }
+ }
+ return StringPiece::npos;
+}
+
+StringPiece::size_type find_first_not_of(const StringPiece& self,
+ char c,
+ StringPiece::size_type pos) {
+ if (self.size() == 0)
+ return StringPiece::npos;
+
+ for (; pos < self.size(); ++pos) {
+ if (self.data()[pos] != c) {
+ return pos;
+ }
+ }
+ return StringPiece::npos;
+}
+
+StringPiece::size_type find_last_of(const StringPiece& self,
+ const StringPiece& s,
+ StringPiece::size_type pos) {
+ if (self.size() == 0 || s.size() == 0)
+ return StringPiece::npos;
+
+ // Avoid the cost of BuildLookupTable() for a single-character search.
+ if (s.size() == 1)
+ return rfind(self, s.data()[0], pos);
+
+ bool lookup[UCHAR_MAX + 1] = { false };
+ BuildLookupTable(s, lookup);
+ for (StringPiece::size_type i = std::min(pos, self.size() - 1); ; --i) {
+ if (lookup[static_cast<unsigned char>(self.data()[i])])
+ return i;
+ if (i == 0)
+ break;
+ }
+ return StringPiece::npos;
+}
+
+StringPiece::size_type find_last_not_of(const StringPiece& self,
+ const StringPiece& s,
+ StringPiece::size_type pos) {
+ if (self.size() == 0)
+ return StringPiece::npos;
+
+ StringPiece::size_type i = std::min(pos, self.size() - 1);
+ if (s.size() == 0)
+ return i;
+
+ // Avoid the cost of BuildLookupTable() for a single-character search.
+ if (s.size() == 1)
+ return find_last_not_of(self, s.data()[0], pos);
+
+ bool lookup[UCHAR_MAX + 1] = { false };
+ BuildLookupTable(s, lookup);
+ for (; ; --i) {
+ if (!lookup[static_cast<unsigned char>(self.data()[i])])
+ return i;
+ if (i == 0)
+ break;
+ }
+ return StringPiece::npos;
+}
+
+StringPiece::size_type find_last_not_of(const StringPiece& self,
+ char c,
+ StringPiece::size_type pos) {
+ if (self.size() == 0)
+ return StringPiece::npos;
+
+ for (StringPiece::size_type i = std::min(pos, self.size() - 1); ; --i) {
+ if (self.data()[i] != c)
+ return i;
+ if (i == 0)
+ break;
+ }
+ return StringPiece::npos;
+}
+
+StringPiece substr(const StringPiece& self,
+ StringPiece::size_type pos,
+ StringPiece::size_type n) {
+ if (pos > self.size()) pos = self.size();
+ if (n > self.size() - pos) n = self.size() - pos;
+ return StringPiece(self.data() + pos, n);
+}
+
+} // namespace internal
+} // namespace base