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// Copyright (c) 2021 Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef COMMON_STRING_VIEW_H__
#define COMMON_STRING_VIEW_H__
#include <cassert>
#include <cstring>
#include <ostream>
#include "common/using_std_string.h"
namespace google_breakpad {
// A StringView is a string reference to a string object, but not own the
// string object. It's a compatibile layer until we can use std::string_view in
// C++17.
class StringView {
private:
// The start of the string, in an external buffer. It doesn't have to be
// null-terminated.
const char* data_ = "";
size_t length_ = 0;
public:
// Construct an empty StringView.
StringView() = default;
// Disallow construct StringView from nullptr.
StringView(std::nullptr_t) = delete;
// Construct a StringView from a cstring.
StringView(const char* str) : data_(str) {
assert(str);
length_ = strlen(str);
}
// Construct a StringView from a cstring with fixed length.
StringView(const char* str, size_t length) : data_(str), length_(length) {
assert(str);
}
// Construct a StringView from an std::string.
StringView(const string& str) : data_(str.data()), length_(str.length()) {}
string str() const { return string(data_, length_); }
const char* data() const { return data_; }
bool empty() const { return length_ == 0; }
size_t size() const { return length_; }
int compare(StringView rhs) const {
size_t min_len = std::min(size(), rhs.size());
int res = memcmp(data_, rhs.data(), min_len);
if (res != 0)
return res;
if (size() == rhs.size())
return 0;
return size() < rhs.size() ? -1 : 1;
}
};
inline bool operator==(StringView lhs, StringView rhs) {
return lhs.compare(rhs) == 0;
}
inline bool operator!=(StringView lhs, StringView rhs) {
return lhs.compare(rhs) != 0;
}
inline bool operator<(StringView lhs, StringView rhs) {
return lhs.compare(rhs) < 0;
}
inline bool operator>(StringView lhs, StringView rhs) {
return lhs.compare(rhs) > 0;
}
inline std::ostream& operator<<(std::ostream& os, StringView s) {
os << s.str();
return os;
}
} // namespace google_breakpad
#endif // COMMON_STRING_VIEW_H__
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