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diff --git a/src/common/string_view.h b/src/common/string_view.h
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+++ b/src/common/string_view.h
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+// Copyright 2021 Google LLC
+//
+// 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 LLC 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__