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+/* If you use ICU in your program, then compile with -DUSE_ICU -licui18n. If
+ * you don't use ICU, then this will use the Google implementation from Chrome.
+ * This has been modified from the original version to let you choose.
+ */
+
+// Copyright 2008, 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.
+// Copied from strings/stringpiece.h with modifications
+//
+// A string-like object that points to a sized piece of memory.
+//
+// Functions or methods may use const StringPiece& parameters to accept either
+// a "const char*" or a "string" value that will be implicitly converted to
+// a StringPiece. The implicit conversion means that it is often appropriate
+// to include this .h file in other files rather than forward-declaring
+// StringPiece as would be appropriate for most other Google classes.
+//
+// Systematic usage of StringPiece is encouraged as it will reduce unnecessary
+// conversions from "const char*" to "string" and back again.
+//
+
+#ifndef BASE_STRING_PIECE_H__
+#define BASE_STRING_PIECE_H__
+
+//Uncomment this line if you use ICU in your code.
+//#define USE_ICU
+//Uncomment this line if you want boost hashing for your StringPieces.
+//#define USE_BOOST
+
+#include <cstring>
+#include <iosfwd>
+
+#ifdef USE_ICU
+#include <unicode/stringpiece.h>
+U_NAMESPACE_BEGIN
+#else
+
+#include <algorithm>
+#include <ostream>
+#include <string>
+#include <string.h>
+
+class StringPiece {
+ public:
+ typedef size_t size_type;
+
+ private:
+ const char* ptr_;
+ size_type length_;
+
+ public:
+ // We provide non-explicit singleton constructors so users can pass
+ // in a "const char*" or a "string" wherever a "StringPiece" is
+ // expected.
+ StringPiece() : ptr_(NULL), length_(0) { }
+ StringPiece(const char* str)
+ : ptr_(str), length_((str == NULL) ? 0 : strlen(str)) { }
+ StringPiece(const std::string& str)
+ : ptr_(str.data()), length_(str.size()) { }
+ StringPiece(const char* offset, size_type len)
+ : ptr_(offset), length_(len) { }
+
+ // data() may return a pointer to a buffer with embedded NULs, and the
+ // returned buffer may or may not be null terminated. Therefore it is
+ // typically a mistake to pass data() to a routine that expects a NUL
+ // terminated string.
+ const char* data() const { return ptr_; }
+ size_type size() const { return length_; }
+ size_type length() const { return length_; }
+ bool empty() const { return length_ == 0; }
+
+ void clear() { ptr_ = NULL; length_ = 0; }
+ void set(const char* data, size_type len) { ptr_ = data; length_ = len; }
+ void set(const char* str) {
+ ptr_ = str;
+ length_ = str ? strlen(str) : 0;
+ }
+ void set(const void* data, size_type len) {
+ ptr_ = reinterpret_cast<const char*>(data);
+ length_ = len;
+ }
+
+ char operator[](size_type i) const { return ptr_[i]; }
+
+ void remove_prefix(size_type n) {
+ ptr_ += n;
+ length_ -= n;
+ }
+
+ void remove_suffix(size_type n) {
+ length_ -= n;
+ }
+
+ int compare(const StringPiece& x) const {
+ int r = wordmemcmp(ptr_, x.ptr_, std::min(length_, x.length_));
+ if (r == 0) {
+ if (length_ < x.length_) r = -1;
+ else if (length_ > x.length_) r = +1;
+ }
+ return r;
+ }
+
+ std::string as_string() const {
+ // std::string doesn't like to take a NULL pointer even with a 0 size.
+ return std::string(!empty() ? data() : "", size());
+ }
+
+ void CopyToString(std::string* target) const;
+ void AppendToString(std::string* target) const;
+
+ // Does "this" start with "x"
+ bool starts_with(const StringPiece& x) const {
+ return ((length_ >= x.length_) &&
+ (wordmemcmp(ptr_, x.ptr_, x.length_) == 0));
+ }
+
+ // Does "this" end with "x"
+ bool ends_with(const StringPiece& x) const {
+ return ((length_ >= x.length_) &&
+ (wordmemcmp(ptr_ + (length_-x.length_), x.ptr_, x.length_) == 0));
+ }
+
+ // standard STL container boilerplate
+ typedef char value_type;
+ typedef const char* pointer;
+ typedef const char& reference;
+ typedef const char& const_reference;
+ typedef ptrdiff_t difference_type;
+ static const size_type npos;
+ typedef const char* const_iterator;
+ typedef const char* iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+ iterator begin() const { return ptr_; }
+ iterator end() const { return ptr_ + length_; }
+ const_reverse_iterator rbegin() const {
+ return const_reverse_iterator(ptr_ + length_);
+ }
+ const_reverse_iterator rend() const {
+ return const_reverse_iterator(ptr_);
+ }
+
+ size_type max_size() const { return length_; }
+ size_type capacity() const { return length_; }
+
+ size_type copy(char* buf, size_type n, size_type pos = 0) const;
+
+ size_type find(const StringPiece& s, size_type pos = 0) const;
+ size_type find(char c, size_type pos = 0) const;
+ size_type rfind(const StringPiece& s, size_type pos = npos) const;
+ size_type rfind(char c, size_type pos = npos) const;
+
+ size_type find_first_of(const StringPiece& s, size_type pos = 0) const;
+ size_type find_first_of(char c, size_type pos = 0) const {
+ return find(c, pos);
+ }
+ size_type find_first_not_of(const StringPiece& s, size_type pos = 0) const;
+ size_type find_first_not_of(char c, size_type pos = 0) const;
+ size_type find_last_of(const StringPiece& s, size_type pos = npos) const;
+ size_type find_last_of(char c, size_type pos = npos) const {
+ return rfind(c, pos);
+ }
+ size_type find_last_not_of(const StringPiece& s, size_type pos = npos) const;
+ size_type find_last_not_of(char c, size_type pos = npos) const;
+
+ StringPiece substr(size_type pos, size_type n = npos) const;
+
+ static int wordmemcmp(const char* p, const char* p2, size_type N) {
+ return memcmp(p, p2, N);
+ }
+};
+
+inline bool operator==(const StringPiece& x, const StringPiece& y) {
+ if (x.size() != y.size())
+ return false;
+
+ return std::memcmp(x.data(), y.data(), x.size()) == 0;
+}
+
+inline bool operator!=(const StringPiece& x, const StringPiece& y) {
+ return !(x == y);
+}
+
+#endif
+
+inline bool operator<(const StringPiece& x, const StringPiece& y) {
+ const int r = std::memcmp(x.data(), y.data(),
+ std::min(x.size(), y.size()));
+ return ((r < 0) || ((r == 0) && (x.size() < y.size())));
+}
+
+inline bool operator>(const StringPiece& x, const StringPiece& y) {
+ return y < x;
+}
+
+inline bool operator<=(const StringPiece& x, const StringPiece& y) {
+ return !(x > y);
+}
+
+inline bool operator>=(const StringPiece& x, const StringPiece& y) {
+ return !(x < y);
+}
+
+// allow StringPiece to be logged (needed for unit testing).
+extern std::ostream& operator<<(std::ostream& o, const StringPiece& piece);
+
+#ifdef USE_BOOST
+size_t hash_value(const StringPiece &str);
+
+/* Support for lookup of StringPiece in boost::unordered_map<std::string> */
+struct StringPieceCompatibleHash : public std::unary_function<const StringPiece &, size_t> {
+ size_t operator()(const StringPiece &str) const {
+ return hash_value(str);
+ }
+};
+
+struct StringPieceCompatibleEquals : public std::binary_function<const StringPiece &, const std::string &, bool> {
+ bool operator()(const StringPiece &first, const StringPiece &second) const {
+ return first == second;
+ }
+};
+template <class T> typename T::const_iterator FindStringPiece(const T &t, const StringPiece &key) {
+ return t.find(key, StringPieceCompatibleHash(), StringPieceCompatibleEquals());
+}
+template <class T> typename T::iterator FindStringPiece(T &t, const StringPiece &key) {
+ return t.find(key, StringPieceCompatibleHash(), StringPieceCompatibleEquals());
+}
+#endif
+
+#ifdef USE_ICU
+U_NAMESPACE_END
+#endif
+
+#endif // BASE_STRING_PIECE_H__