Fill out the rest of the StringPiece functions for 16-bit.

base/strings/string_piece.h

 // 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.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
@@ skipping 21 matching lines @@
 #include "base/basictypes.h"
 #include "base/containers/hash_tables.h"
 #include "base/strings/string16.h"
 
 namespace base {
 
 template <typename STRING_TYPE> class BasicStringPiece;
 typedef BasicStringPiece<std::string> StringPiece;
 typedef BasicStringPiece<string16> StringPiece16;
 
+// internal --------------------------------------------------------------------
+
+// Many of the StringPiece functions use different implementations for the
+// 8-bit and 16-bit versions, and we don't want lots of template expansions in
+// this (very common) header that will slow down compilation.
+//
+// So here we define overloaded functions called by the StringPiece template.
+// For those that share an implementation, the two versions will expand to a
+// template internal to the .cc file.
 namespace internal {
 
+BASE_EXPORT void CopyToString(const StringPiece& self, std::string* target);
+BASE_EXPORT void CopyToString(const StringPiece16& self, string16* target);
+
+BASE_EXPORT void AppendToString(const StringPiece& self, std::string* target);
+BASE_EXPORT void AppendToString(const StringPiece16& self, string16* target);
+
+BASE_EXPORT size_t copy(const StringPiece& self,
+                        char* buf,
+                        size_t n,
+                        size_t pos);
+BASE_EXPORT size_t copy(const StringPiece16& self,
+                        char16* buf,
+                        size_t n,
+                        size_t pos);
+
+BASE_EXPORT size_t find(const StringPiece& self,
+                        const StringPiece& s,
+                        size_t pos);
+BASE_EXPORT size_t find(const StringPiece16& self,
+                        const StringPiece16& s,
+                        size_t pos);
+BASE_EXPORT size_t find(const StringPiece& self,
+                        char c,
+                        size_t pos);
+BASE_EXPORT size_t find(const StringPiece16& self,
+                        char16 c,
+                        size_t pos);
+
+BASE_EXPORT size_t rfind(const StringPiece& self,
+                         const StringPiece& s,
+                         size_t pos);
+BASE_EXPORT size_t rfind(const StringPiece16& self,
+                         const StringPiece16& s,
+                         size_t pos);
+BASE_EXPORT size_t rfind(const StringPiece& self,
+                         char c,
+                         size_t pos);
+BASE_EXPORT size_t rfind(const StringPiece16& self,
+                         char16 c,
+                         size_t pos);
+
+BASE_EXPORT size_t find_first_of(const StringPiece& self,
+                                 const StringPiece& s,
+                                 size_t pos);
+BASE_EXPORT size_t find_first_of(const StringPiece16& self,
+                                 const StringPiece16& s,
+                                 size_t pos);
+
+BASE_EXPORT size_t find_first_not_of(const StringPiece& self,
+                                     const StringPiece& s,
+                                     size_t pos);
+BASE_EXPORT size_t find_first_not_of(const StringPiece16& self,
+                                     const StringPiece16& s,
+                                     size_t pos);
+BASE_EXPORT size_t find_first_not_of(const StringPiece& self,
+                                     char c,
+                                     size_t pos);
+BASE_EXPORT size_t find_first_not_of(const StringPiece16& self,
+                                     char16 c,
+                                     size_t pos);
+
+BASE_EXPORT size_t find_last_of(const StringPiece& self,
+                                const StringPiece& s,
+                                size_t pos);
+BASE_EXPORT size_t find_last_of(const StringPiece16& self,
+                                const StringPiece16& s,
+                                size_t pos);
+BASE_EXPORT size_t find_last_of(const StringPiece& self,
+                                char c,
+                                size_t pos);
+BASE_EXPORT size_t find_last_of(const StringPiece16& self,
+                                char16 c,
+                                size_t pos);
+
+BASE_EXPORT size_t find_last_not_of(const StringPiece& self,
+                                    const StringPiece& s,
+                                    size_t pos);
+BASE_EXPORT size_t find_last_not_of(const StringPiece16& self,
+                                    const StringPiece16& s,
+                                    size_t pos);
+BASE_EXPORT size_t find_last_not_of(const StringPiece16& self,
+                                    char16 c,
+                                    size_t pos);
+BASE_EXPORT size_t find_last_not_of(const StringPiece& self,
+                                    char c,
+                                    size_t pos);
+
+BASE_EXPORT StringPiece substr(const StringPiece& self,
+                               size_t pos,
+                               size_t n);
+BASE_EXPORT StringPiece16 substr(const StringPiece16& self,
+                                 size_t pos,
+                                 size_t n);
+
+}  // namespace internal
+
+// BasicStringPiece ------------------------------------------------------------
+
 // 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 {
+//
+// This is templatized by string class type rather than character type, so
+// BasicStringPiece<std::string> or BasicStringPiece<base::string16>.
+template <typename STRING_TYPE> class BasicStringPiece {
  public:
-  // standard STL container boilerplate
+  // 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)
+  BasicStringPiece() : ptr_(NULL), length_(0) {}
+  BasicStringPiece(const value_type* str)
       : ptr_(str),
         length_((str == NULL) ? 0 : STRING_TYPE::traits_type::length(str)) {}
-  StringPieceDetail(const STRING_TYPE& str)
+  BasicStringPiece(const STRING_TYPE& str)
       : ptr_(str.data()), length_(str.size()) {}
-  StringPieceDetail(const value_type* offset, size_type len)
+  BasicStringPiece(const value_type* offset, size_type len)
       : ptr_(offset), length_(len) {}
-  StringPieceDetail(const typename STRING_TYPE::const_iterator& begin,
+  BasicStringPiece(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_; }
@@ skipping 50 matching lines @@
 
   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);
   }
 
+  // Sets the value of the given string target type to be the current string.
+  // This saves a temporary over doing |a = b.as_string()|
+  void CopyToString(STRING_TYPE* target) const {
+    internal::CopyToString(*this, target);
+  }
+
+  void AppendToString(STRING_TYPE* target) const {
+    internal::AppendToString(*this, target);
+  }
+
+  size_type copy(value_type* buf, size_type n, size_type pos = 0) const {
+    return internal::copy(*this, buf, n, pos);
+  }
+
+  // Does "this" start with "x"
+  bool starts_with(const BasicStringPiece& x) const {
+    return ((this->length_ >= x.length_) &&
+            (wordmemcmp(this->ptr_, x.ptr_, x.length_) == 0));
+  }
+
+  // Does "this" end with "x"
+  bool ends_with(const BasicStringPiece& x) const {
+    return ((this->length_ >= x.length_) &&
+            (wordmemcmp(this->ptr_ + (this->length_-x.length_),
+                        x.ptr_, x.length_) == 0));
+  }
+
+  // find: Search for a character or substring at a given offset.
+  size_type find(const BasicStringPiece<STRING_TYPE>& s,
+                 size_type pos = 0) const {
+    return internal::find(*this, s, pos);
+  }
+  size_type find(value_type c, size_type pos = 0) const {
+    return internal::find(*this, c, pos);
+  }
+
+  // rfind: Reverse find.
+  size_type rfind(const BasicStringPiece& s,
+                  size_type pos = BasicStringPiece::npos) const {
+    return internal::rfind(*this, s, pos);
+  }
+  size_type rfind(value_type c, size_type pos = BasicStringPiece::npos) const {
+    return internal::rfind(*this, c, pos);
+  }
+
+  // find_first_of: Find the first occurence of one of a set of characters.
+  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(value_type c, size_type pos = 0) const {
+    return find(c, pos);
+  }
+
+  // find_first_not_of: Find the first occurence not of a set of characters.
+  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(value_type c, size_type pos = 0) const {
+    return internal::find_first_not_of(*this, c, pos);
+  }
+
+  // find_last_of: Find the last occurence of one of a set of characters.
+  size_type find_last_of(const BasicStringPiece& s,
+                         size_type pos = BasicStringPiece::npos) const {
+    return internal::find_last_of(*this, s, pos);
+  }
+  size_type find_last_of(value_type c,
+                         size_type pos = BasicStringPiece::npos) const {
+    return rfind(c, pos);
+  }
+
+  // find_last_not_of: Find the last occurence not of a set of characters.
+  size_type find_last_not_of(const BasicStringPiece& s,
+                             size_type pos = BasicStringPiece::npos) const {
+    return internal::find_last_not_of(*this, s, pos);
+  }
+  size_type find_last_not_of(value_type c,
+                             size_type pos = BasicStringPiece::npos) const {
+    return internal::find_last_not_of(*this, c, pos);
+  }
+
+  // substr.
+  BasicStringPiece substr(size_type pos,
+                          size_type n = BasicStringPiece::npos) const {
+    return internal::substr(*this, pos, 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);
+const typename BasicStringPiece<STRING_TYPE>::size_type
+BasicStringPiece<STRING_TYPE>::npos =
+    typename BasicStringPiece<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>;
+extern template class BASE_EXPORT BasicStringPiece<std::string>;
+extern template class BASE_EXPORT BasicStringPiece<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
+// StingPiece operators --------------------------------------------------------
 
 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);
 }
 
+// StringPiece16 operators -----------------------------------------------------
+
 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);
 }
@@ skipping 14 matching lines @@
 
 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
 
+// Hashing ---------------------------------------------------------------------
+
 // 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/containers/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)                                    \
@@ skipping 23 matching lines @@
 }
 inline size_t hash_value(const base::StringPiece16& sp16) {
   HASH_STRING_PIECE(base::StringPiece16, sp16);
 }
 
 #endif  // COMPILER
 
 }  // namespace BASE_HASH_NAMESPACE
 
 #endif  // BASE_STRINGS_STRING_PIECE_H_