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// 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 <algorithm>
#include <ostream>
#include "base/string_piece.h"
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
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