diff options
Diffstat (limited to 'base/string_piece.h')
| -rw-r--r-- | base/string_piece.h | 451 |
1 files changed, 3 insertions, 448 deletions
diff --git a/base/string_piece.h b/base/string_piece.h index 416fca8..12b9a34 100644 --- a/base/string_piece.h +++ b/base/string_piece.h @@ -1,451 +1,6 @@ -// Copyright (c) 2012 The Chromium Authors. All rights reserved. +// Copyright (c) 2013 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.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. -// -// StringPiece16 is similar to StringPiece but for base::string16 instead of -// std::string. We do not define as large of a subset of the STL functions -// from basic_string as in StringPiece, but this can be changed if these -// functions (find, find_first_of, etc.) are found to be useful in this context. -// -#ifndef BASE_STRING_PIECE_H_ -#define BASE_STRING_PIECE_H_ - -#include <stddef.h> - -#include <iosfwd> -#include <string> - -#include "base/base_export.h" -#include "base/basictypes.h" -#include "base/hash_tables.h" -#include "base/string16.h" - -namespace base { - -template <typename STRING_TYPE> class BasicStringPiece; -typedef BasicStringPiece<std::string> StringPiece; -typedef BasicStringPiece<string16> StringPiece16; - -namespace internal { - -// Defines the types, methods, operators, and data members common to both -// StringPiece and StringPiece16. Do not refer to this class directly, but -// rather to BasicStringPiece, StringPiece, or StringPiece16. -template <typename STRING_TYPE> class StringPieceDetail { - public: - // standard STL container boilerplate - typedef size_t size_type; - typedef typename STRING_TYPE::value_type value_type; - typedef const value_type* pointer; - typedef const value_type& reference; - typedef const value_type& const_reference; - typedef ptrdiff_t difference_type; - typedef const value_type* const_iterator; - typedef std::reverse_iterator<const_iterator> const_reverse_iterator; - - static const size_type npos; - - public: - // We provide non-explicit singleton constructors so users can pass - // in a "const char*" or a "string" wherever a "StringPiece" is - // expected (likewise for char16, string16, StringPiece16). - StringPieceDetail() : ptr_(NULL), length_(0) {} - StringPieceDetail(const value_type* str) - : ptr_(str), - length_((str == NULL) ? 0 : STRING_TYPE::traits_type::length(str)) {} - StringPieceDetail(const STRING_TYPE& str) - : ptr_(str.data()), length_(str.size()) {} - StringPieceDetail(const value_type* offset, size_type len) - : ptr_(offset), length_(len) {} - StringPieceDetail(const typename STRING_TYPE::const_iterator& begin, - const typename STRING_TYPE::const_iterator& end) - : ptr_((end > begin) ? &(*begin) : NULL), - length_((end > begin) ? (size_type)(end - begin) : 0) {} - - // 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 value_type* 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 value_type* data, size_type len) { - ptr_ = data; - length_ = len; - } - void set(const value_type* str) { - ptr_ = str; - length_ = str ? STRING_TYPE::traits_type::length(str) : 0; - } - - value_type 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 BasicStringPiece<STRING_TYPE>& x) const { - int r = wordmemcmp( - ptr_, x.ptr_, (length_ < x.length_ ? length_ : x.length_)); - if (r == 0) { - if (length_ < x.length_) r = -1; - else if (length_ > x.length_) r = +1; - } - return r; - } - - STRING_TYPE as_string() const { - // std::string doesn't like to take a NULL pointer even with a 0 size. - return empty() ? STRING_TYPE() : STRING_TYPE(data(), size()); - } - - const_iterator begin() const { return ptr_; } - const_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_; } - - static int wordmemcmp(const value_type* p, - const value_type* p2, - size_type N) { - return STRING_TYPE::traits_type::compare(p, p2, N); - } - - protected: - const value_type* ptr_; - size_type length_; -}; - -template <typename STRING_TYPE> -const typename StringPieceDetail<STRING_TYPE>::size_type -StringPieceDetail<STRING_TYPE>::npos = - typename StringPieceDetail<STRING_TYPE>::size_type(-1); - -// MSVC doesn't like complex extern templates and DLLs. -#if !defined(COMPILER_MSVC) -extern template class BASE_EXPORT StringPieceDetail<std::string>; -extern template class BASE_EXPORT StringPieceDetail<string16>; -#endif - -BASE_EXPORT void CopyToString(const StringPiece& self, std::string* target); -BASE_EXPORT void AppendToString(const StringPiece& self, std::string* target); -BASE_EXPORT StringPieceDetail<std::string>::size_type copy( - const StringPiece& self, - char* buf, - StringPieceDetail<std::string>::size_type n, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type find( - const StringPiece& self, - const StringPiece& s, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type find( - const StringPiece& self, - char c, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type rfind( - const StringPiece& self, - const StringPiece& s, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type rfind( - const StringPiece& self, - char c, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type find_first_of( - const StringPiece& self, - const StringPiece& s, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type find_first_not_of( - const StringPiece& self, - const StringPiece& s, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type find_first_not_of( - const StringPiece& self, - char c, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type find_last_of( - const StringPiece& self, - const StringPiece& s, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type find_last_of( - const StringPiece& self, - char c, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type find_last_not_of( - const StringPiece& self, - const StringPiece& s, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPieceDetail<std::string>::size_type find_last_not_of( - const StringPiece& self, - char c, - StringPieceDetail<std::string>::size_type pos); -BASE_EXPORT StringPiece substr(const StringPiece& self, - StringPieceDetail<std::string>::size_type pos, - StringPieceDetail<std::string>::size_type n); -} // namespace internal - -// Defines the template type that is instantiated as either StringPiece or -// StringPiece16. -template <typename STRING_TYPE> class BasicStringPiece : - public internal::StringPieceDetail<STRING_TYPE> { - public: - typedef typename internal::StringPieceDetail<STRING_TYPE>::value_type - value_type; - typedef typename internal::StringPieceDetail<STRING_TYPE>::size_type - size_type; - - BasicStringPiece() {} - BasicStringPiece(const value_type*str) - : internal::StringPieceDetail<STRING_TYPE>(str) {} - BasicStringPiece(const STRING_TYPE& str) - : internal::StringPieceDetail<STRING_TYPE>(str) {} - BasicStringPiece(const value_type* offset, size_type len) - : internal::StringPieceDetail<STRING_TYPE>(offset, len) {} - BasicStringPiece(const typename STRING_TYPE::const_iterator& begin, - const typename STRING_TYPE::const_iterator& end) - : internal::StringPieceDetail<STRING_TYPE>(begin, end) {} -}; - -// Specializes BasicStringPiece for std::string to add a few operations that -// are not needed for string16. -template <> class BasicStringPiece<std::string> : - public internal::StringPieceDetail<std::string> { - public: - BasicStringPiece() {} - BasicStringPiece(const char* str) - : internal::StringPieceDetail<std::string>(str) {} - BasicStringPiece(const std::string& str) - : internal::StringPieceDetail<std::string>(str) {} - BasicStringPiece(const char* offset, size_type len) - : internal::StringPieceDetail<std::string>(offset, len) {} - BasicStringPiece(const std::string::const_iterator& begin, - const std::string::const_iterator& end) - : internal::StringPieceDetail<std::string>(begin, end) {} - - // Prevent the following overload of set() from hiding the definitions in the - // base class. - using internal::StringPieceDetail<std::string>::set; - - void set(const void* data, size_type len) { - ptr_ = reinterpret_cast<const value_type*>(data); - length_ = len; - } - - void CopyToString(std::string* target) const { - internal::CopyToString(*this, target); - } - - void AppendToString(std::string* target) const { - internal::AppendToString(*this, target); - } - - // Does "this" start with "x" - bool starts_with(const BasicStringPiece& x) const { - return ((length_ >= x.length_) && - (wordmemcmp(ptr_, x.ptr_, x.length_) == 0)); - } - - // Does "this" end with "x" - bool ends_with(const BasicStringPiece& x) const { - return ((length_ >= x.length_) && - (wordmemcmp(ptr_ + (length_-x.length_), x.ptr_, x.length_) == 0)); - } - - size_type copy(char* buf, size_type n, size_type pos = 0) const { - return internal::copy(*this, buf, n, pos); - } - - size_type find(const BasicStringPiece& s, size_type pos = 0) const { - return internal::find(*this, s, pos); - } - - size_type find(char c, size_type pos = 0) const { - return internal::find(*this, c, pos); - } - - size_type rfind(const BasicStringPiece& s, size_type pos = npos) const { - return internal::rfind(*this, s, pos); - } - - size_type rfind(char c, size_type pos = npos) const { - return internal::rfind(*this, c, pos); - } - - size_type find_first_of(const BasicStringPiece& s, size_type pos = 0) const { - return internal::find_first_of(*this, s, pos); - } - - size_type find_first_of(char c, size_type pos = 0) const { - return find(c, pos); - } - - size_type find_first_not_of(const BasicStringPiece& s, - size_type pos = 0) const { - return internal::find_first_not_of(*this, s, pos); - } - - size_type find_first_not_of(char c, size_type pos = 0) const { - return internal::find_first_not_of(*this, c, pos); - } - - size_type find_last_of(const BasicStringPiece& s, - size_type pos = npos) const { - return internal::find_last_of(*this, s, pos); - } - - size_type find_last_of(char c, size_type pos = npos) const { - return rfind(c, pos); - } - - size_type find_last_not_of(const BasicStringPiece& s, - size_type pos = npos) const { - return internal::find_last_not_of(*this, s, pos); - } - - size_type find_last_not_of(char c, size_type pos = npos) const { - return internal::find_last_not_of(*this, c, pos); - } - - BasicStringPiece substr(size_type pos, size_type n = npos) const { - return internal::substr(*this, pos, n); - } -}; - -// MSVC doesn't like complex extern templates and DLLs. -#if !defined(COMPILER_MSVC) -// We can't explicitly declare the std::string instantiation here because it was -// already instantiated when specialized, above. Not only is it a no-op, but -// currently it also crashes Clang (see http://crbug.com/107412). -extern template class BASE_EXPORT BasicStringPiece<string16>; -#endif - -BASE_EXPORT bool operator==(const StringPiece& x, const StringPiece& y); - -inline bool operator!=(const StringPiece& x, const StringPiece& y) { - return !(x == y); -} - -inline bool operator<(const StringPiece& x, const StringPiece& y) { - const int r = StringPiece::wordmemcmp( - x.data(), y.data(), (x.size() < y.size() ? 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); -} - -inline bool operator==(const StringPiece16& x, const StringPiece16& y) { - if (x.size() != y.size()) - return false; - - return StringPiece16::wordmemcmp(x.data(), y.data(), x.size()) == 0; -} - -inline bool operator!=(const StringPiece16& x, const StringPiece16& y) { - return !(x == y); -} - -inline bool operator<(const StringPiece16& x, const StringPiece16& y) { - const int r = StringPiece16::wordmemcmp( - x.data(), y.data(), (x.size() < y.size() ? x.size() : y.size())); - return ((r < 0) || ((r == 0) && (x.size() < y.size()))); -} - -inline bool operator>(const StringPiece16& x, const StringPiece16& y) { - return y < x; -} - -inline bool operator<=(const StringPiece16& x, const StringPiece16& y) { - return !(x > y); -} - -inline bool operator>=(const StringPiece16& x, const StringPiece16& y) { - return !(x < y); -} - -BASE_EXPORT std::ostream& operator<<(std::ostream& o, - const StringPiece& piece); - -} // namespace base - -// We provide appropriate hash functions so StringPiece and StringPiece16 can -// be used as keys in hash sets and maps. - -// This hash function is copied from base/hash_tables.h. We don't use the -// ones already defined for string and string16 directly because it would -// require the string constructors to be called, which we don't want. -#define HASH_STRING_PIECE(StringPieceType, string_piece) \ - std::size_t result = 0; \ - for (StringPieceType::const_iterator i = string_piece.begin(); \ - i != string_piece.end(); ++i) \ - result = (result * 131) + *i; \ - return result; \ - -namespace BASE_HASH_NAMESPACE { -#if defined(COMPILER_GCC) - -template<> -struct hash<base::StringPiece> { - std::size_t operator()(const base::StringPiece& sp) const { - HASH_STRING_PIECE(base::StringPiece, sp); - } -}; -template<> -struct hash<base::StringPiece16> { - std::size_t operator()(const base::StringPiece16& sp16) const { - HASH_STRING_PIECE(base::StringPiece16, sp16); - } -}; - -#elif defined(COMPILER_MSVC) - -inline size_t hash_value(const base::StringPiece& sp) { - HASH_STRING_PIECE(base::StringPiece, sp); -} -inline size_t hash_value(const base::StringPiece16& sp16) { - HASH_STRING_PIECE(base::StringPiece16, sp16); -} - -#endif // COMPILER - -} // namespace BASE_HASH_NAMESPACE - -#endif // BASE_STRING_PIECE_H_ +// TODO(brettw) move callers to using the new location +#include "base/strings/string_piece.h" |