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

base/strings/string_piece.cc

 // 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.cc with modifications
 
 #include "base/strings/string_piece.h"
 
 #include <algorithm>
 #include <ostream>
 
 namespace base {
+namespace {
+
+// For each character in characters_wanted, sets the index corresponding
+// to the ASCII code of that character to 1 in table.  This is used by
+// the find_.*_of methods below to tell whether or not a character is in
+// the lookup table in constant time.
+// The argument `table' must be an array that is large enough to hold all
+// the possible values of an unsigned char.  Thus it should be be declared
+// as follows:
+//   bool table[UCHAR_MAX + 1]
+inline void BuildLookupTable(const StringPiece& characters_wanted,
+                             bool* table) {
+  const size_t length = characters_wanted.length();
+  const char* const data = characters_wanted.data();
+  for (size_t i = 0; i < length; ++i) {
+    table[static_cast<unsigned char>(data[i])] = true;
+  }
+}
+
+}  // namespace
 
 // MSVC doesn't like complex extern templates and DLLs.
 #if !defined(COMPILER_MSVC)
-namespace internal {
-template class StringPieceDetail<std::string>;
-template class StringPieceDetail<string16>;
-}  // namespace internal
-
+template class BasicStringPiece<std::string>;
 template class BasicStringPiece<string16>;
 #endif
 
 bool operator==(const StringPiece& x, const StringPiece& y) {
   if (x.size() != y.size())
     return false;
 
   return StringPiece::wordmemcmp(x.data(), y.data(), x.size()) == 0;
 }
 
 std::ostream& operator<<(std::ostream& o, const StringPiece& piece) {
   o.write(piece.data(), static_cast<std::streamsize>(piece.size()));
   return o;
 }
 
 namespace internal {
-void CopyToString(const StringPiece& self, std::string* target) {
-  target->assign(!self.empty() ? self.data() : "", self.size());
+
+template<typename STR>
+void CopyToStringT(const BasicStringPiece<STR>& self, STR* target) {
+  if (self.empty())
+    target->clear();
+  else
+    target->assign(self.data(), self.size());
 }
 
-void AppendToString(const StringPiece& self, std::string* target) {
+void CopyToString(const StringPiece& self, std::string* target) {
+  CopyToStringT(self, target);
+}
+
+void CopyToString(const StringPiece16& self, string16* target) {
+  CopyToStringT(self, target);
+}
+
+template<typename STR>
+void AppendToStringT(const BasicStringPiece<STR>& self, STR* target) {
   if (!self.empty())
     target->append(self.data(), self.size());
 }
 
-StringPiece::size_type copy(const StringPiece& self,
-                            char* buf,
-                            StringPiece::size_type n,
-                            StringPiece::size_type pos) {
-  StringPiece::size_type ret = std::min(self.size() - pos, n);
-  memcpy(buf, self.data() + pos, ret);
+void AppendToString(const StringPiece& self, std::string* target) {
+  AppendToStringT(self, target);
+}
+
+void AppendToString(const StringPiece16& self, string16* target) {
+  AppendToStringT(self, target);
+}
+
+template<typename STR>
+size_t copyT(const BasicStringPiece<STR>& self,
+             typename STR::value_type* buf,
+             size_t n,
+             size_t pos) {
+  size_t ret = std::min(self.size() - pos, n);
+  memcpy(buf, self.data() + pos, ret * sizeof(typename STR::value_type));
   return ret;
 }
 
-StringPiece::size_type find(const StringPiece& self,
-                            const StringPiece& s,
-                            StringPiece::size_type pos) {
-  if (pos > self.size())
-    return StringPiece::npos;
-
-  StringPiece::const_iterator result =
-      std::search(self.begin() + pos, self.end(), s.begin(), s.end());
-  const StringPiece::size_type xpos =
-    static_cast<size_t>(result - self.begin());
-  return xpos + s.size() <= self.size() ? xpos : StringPiece::npos;
+size_t copy(const StringPiece& self, char* buf, size_t n, size_t pos) {
+  return copyT(self, buf, n, pos);
 }
 
-StringPiece::size_type find(const StringPiece& self,
-                            char c,
-                            StringPiece::size_type pos) {
+size_t copy(const StringPiece16& self, char16* buf, size_t n, size_t pos) {
+  return copyT(self, buf, n, pos);
+}
+
+template<typename STR>
+size_t findT(const BasicStringPiece<STR>& self,
+             const BasicStringPiece<STR>& s,
+             size_t pos) {
+  if (pos > self.size())
+    return BasicStringPiece<STR>::npos;
+
+  typename BasicStringPiece<STR>::const_iterator result =
+      std::search(self.begin() + pos, self.end(), s.begin(), s.end());
+  const size_t xpos =
+    static_cast<size_t>(result - self.begin());
+  return xpos + s.size() <= self.size() ? xpos : BasicStringPiece<STR>::npos;
+}
+
+size_t find(const StringPiece& self, const StringPiece& s, size_t pos) {
+  return findT(self, s, pos);
+}
+
+size_t find(const StringPiece16& self, const StringPiece16& s, size_t pos) {
+  return findT(self, s, pos);
+}
+
+template<typename STR>
+size_t findT(const BasicStringPiece<STR>& self,
+             typename STR::value_type c,
+             size_t pos) {
   if (pos >= self.size())
-    return StringPiece::npos;
+    return BasicStringPiece<STR>::npos;
 
-  StringPiece::const_iterator result =
+  typename BasicStringPiece<STR>::const_iterator result =
       std::find(self.begin() + pos, self.end(), c);
   return result != self.end() ?
-      static_cast<size_t>(result - self.begin()) : StringPiece::npos;
+      static_cast<size_t>(result - self.begin()) : BasicStringPiece<STR>::npos;
 }
 
-StringPiece::size_type rfind(const StringPiece& self,
-                             const StringPiece& s,
-                             StringPiece::size_type pos) {
+size_t find(const StringPiece& self, char c, size_t pos) {
+  return findT(self, c, pos);
+}
+
+size_t find(const StringPiece16& self, char16 c, size_t pos) {
+  return findT(self, c, pos);
+}
+
+template<typename STR>
+size_t rfindT(const BasicStringPiece<STR>& self,
+              const BasicStringPiece<STR>& s,
+              size_t pos) {
   if (self.size() < s.size())
-    return StringPiece::npos;
+    return BasicStringPiece<STR>::npos;
 
   if (s.empty())
     return std::min(self.size(), pos);
 
-  StringPiece::const_iterator last =
+  typename BasicStringPiece<STR>::const_iterator last =
       self.begin() + std::min(self.size() - s.size(), pos) + s.size();
-  StringPiece::const_iterator result =
+  typename BasicStringPiece<STR>::const_iterator result =
       std::find_end(self.begin(), last, s.begin(), s.end());
   return result != last ?
-      static_cast<size_t>(result - self.begin()) : StringPiece::npos;
+      static_cast<size_t>(result - self.begin()) : BasicStringPiece<STR>::npos;
 }
 
-StringPiece::size_type rfind(const StringPiece& self,
-                             char c,
-                             StringPiece::size_type pos) {
+size_t rfind(const StringPiece& self, const StringPiece& s, size_t pos) {
+  return rfindT(self, s, pos);
+}
+
+size_t rfind(const StringPiece16& self, const StringPiece16& s, size_t pos) {
+  return rfindT(self, s, pos);
+}
+
+template<typename STR>
+size_t rfindT(const BasicStringPiece<STR>& self,
+              typename STR::value_type c,
+              size_t pos) {
   if (self.size() == 0)
-    return StringPiece::npos;
+    return BasicStringPiece<STR>::npos;
 
-  for (StringPiece::size_type i = std::min(pos, self.size() - 1); ; --i) {
+  for (size_t i = std::min(pos, self.size() - 1); ;
+       --i) {
     if (self.data()[i] == c)
       return i;
     if (i == 0)
       break;
   }
-  return StringPiece::npos;
+  return BasicStringPiece<STR>::npos;
 }
 
-// For each character in characters_wanted, sets the index corresponding
-// to the ASCII code of that character to 1 in table.  This is used by
-// the find_.*_of methods below to tell whether or not a character is in
-// the lookup table in constant time.
-// The argument `table' must be an array that is large enough to hold all
-// the possible values of an unsigned char.  Thus it should be be declared
-// as follows:
-//   bool table[UCHAR_MAX + 1]
-static inline void BuildLookupTable(const StringPiece& characters_wanted,
-                                    bool* table) {
-  const StringPiece::size_type length = characters_wanted.length();
-  const char* const data = characters_wanted.data();
-  for (StringPiece::size_type i = 0; i < length; ++i) {
-    table[static_cast<unsigned char>(data[i])] = true;
-  }
+size_t rfind(const StringPiece& self, char c, size_t pos) {
+  return rfindT(self, c, pos);
 }
 
-StringPiece::size_type find_first_of(const StringPiece& self,
-                                     const StringPiece& s,
-                                     StringPiece::size_type pos) {
+size_t rfind(const StringPiece16& self, char16 c, size_t pos) {
+  return rfindT(self, c, pos);
+}
+
+// 8-bit version using lookup table.
+size_t find_first_of(const StringPiece& self,
+                     const StringPiece& s,
+                     size_t pos) {
   if (self.size() == 0 || s.size() == 0)
     return StringPiece::npos;
 
   // Avoid the cost of BuildLookupTable() for a single-character search.
   if (s.size() == 1)
     return find(self, s.data()[0], pos);
 
   bool lookup[UCHAR_MAX + 1] = { false };
   BuildLookupTable(s, lookup);
-  for (StringPiece::size_type i = pos; i < self.size(); ++i) {
+  for (size_t i = pos; i < self.size(); ++i) {
     if (lookup[static_cast<unsigned char>(self.data()[i])]) {
       return i;
     }
   }
   return StringPiece::npos;
 }
 
-StringPiece::size_type find_first_not_of(const StringPiece& self,
-                                         const StringPiece& s,
-                                         StringPiece::size_type pos) {
+// 16-bit brute force version.
+size_t find_first_of(const StringPiece16& self,
+                     const StringPiece16& s,
+                     size_t pos) {
+  StringPiece16::const_iterator found =
+      std::find_first_of(self.begin() + pos, self.end(), s.begin(), s.end());
+  if (found == self.end())
+    return StringPiece16::npos;
+  return found - self.begin();
+}
+
+// 8-bit version using lookup table.
+size_t find_first_not_of(const StringPiece& self,
+                         const StringPiece& s,
+                         size_t pos) {
   if (self.size() == 0)
     return StringPiece::npos;
 
   if (s.size() == 0)
     return 0;
 
   // Avoid the cost of BuildLookupTable() for a single-character search.
   if (s.size() == 1)
     return find_first_not_of(self, s.data()[0], pos);
 
   bool lookup[UCHAR_MAX + 1] = { false };
   BuildLookupTable(s, lookup);
-  for (StringPiece::size_type i = pos; i < self.size(); ++i) {
+  for (size_t i = pos; i < self.size(); ++i) {
     if (!lookup[static_cast<unsigned char>(self.data()[i])]) {
       return i;
     }
   }
   return StringPiece::npos;
 }
 
-StringPiece::size_type find_first_not_of(const StringPiece& self,
-                                         char c,
-                                         StringPiece::size_type pos) {
+// 16-bit brute-force version.
+BASE_EXPORT size_t find_first_not_of(const StringPiece16& self,
+                                     const StringPiece16& s,
+                                     size_t pos) {
   if (self.size() == 0)
-    return StringPiece::npos;
+    return StringPiece16::npos;
+
+  for (size_t self_i = pos; self_i < self.size(); ++self_i) {
+    bool found = false;
+    for (size_t s_i = 0; s_i < s.size(); ++s_i) {
+      if (self[self_i] == s[s_i]) {
+        found = true;
+        break;
+      }
+    }
+    if (!found)
+      return self_i;
+  }
+  return StringPiece16::npos;
+}
+
+template<typename STR>
+size_t find_first_not_ofT(const BasicStringPiece<STR>& self,
+                          typename STR::value_type c,
+                          size_t pos) {
+  if (self.size() == 0)
+    return BasicStringPiece<STR>::npos;
 
   for (; pos < self.size(); ++pos) {
     if (self.data()[pos] != c) {
       return pos;
     }
   }
-  return StringPiece::npos;
+  return BasicStringPiece<STR>::npos;
 }
 
-StringPiece::size_type find_last_of(const StringPiece& self,
-                                    const StringPiece& s,
-                                    StringPiece::size_type pos) {
+size_t find_first_not_of(const StringPiece& self,
+                         char c,
+                         size_t pos) {
+  return find_first_not_ofT(self, c, pos);
+}
+
+size_t find_first_not_of(const StringPiece16& self,
+                         char16 c,
+                         size_t pos) {
+  return find_first_not_ofT(self, c, pos);
+}
+
+// 8-bit version using lookup table.
+size_t find_last_of(const StringPiece& self, const StringPiece& s, size_t pos) {
   if (self.size() == 0 || s.size() == 0)
     return StringPiece::npos;
 
   // Avoid the cost of BuildLookupTable() for a single-character search.
   if (s.size() == 1)
     return rfind(self, s.data()[0], pos);
 
   bool lookup[UCHAR_MAX + 1] = { false };
   BuildLookupTable(s, lookup);
-  for (StringPiece::size_type i = std::min(pos, self.size() - 1); ; --i) {
+  for (size_t i = std::min(pos, self.size() - 1); ; --i) {
     if (lookup[static_cast<unsigned char>(self.data()[i])])
       return i;
     if (i == 0)
       break;
   }
   return StringPiece::npos;
 }
 
-StringPiece::size_type find_last_not_of(const StringPiece& self,
-                                        const StringPiece& s,
-                                        StringPiece::size_type pos) {
+// 16-bit brute-force version.
+size_t find_last_of(const StringPiece16& self,
+                    const StringPiece16& s,
+                    size_t pos) {
+  if (self.size() == 0)
+    return StringPiece16::npos;
+
+  for (size_t self_i = std::min(pos, self.size() - 1); ;
+       --self_i) {
+    for (size_t s_i = 0; s_i < s.size(); s_i++) {
+      if (self.data()[self_i] == s[s_i])
+        return self_i;
+    }
+    if (self_i == 0)
+      break;
+  }
+  return StringPiece16::npos;
+}
+
+// 8-bit version using lookup table.
+size_t find_last_not_of(const StringPiece& self,
+                        const StringPiece& s,
+                        size_t pos) {
   if (self.size() == 0)
     return StringPiece::npos;
 
-  StringPiece::size_type i = std::min(pos, self.size() - 1);
+  size_t i = std::min(pos, self.size() - 1);
   if (s.size() == 0)
     return i;
 
   // Avoid the cost of BuildLookupTable() for a single-character search.
   if (s.size() == 1)
     return find_last_not_of(self, s.data()[0], pos);
 
   bool lookup[UCHAR_MAX + 1] = { false };
   BuildLookupTable(s, lookup);
   for (; ; --i) {
     if (!lookup[static_cast<unsigned char>(self.data()[i])])
       return i;
     if (i == 0)
       break;
   }
   return StringPiece::npos;
 }
 
-StringPiece::size_type find_last_not_of(const StringPiece& self,
-                                        char c,
-                                        StringPiece::size_type pos) {
+// 16-bit brute-force version.
+size_t find_last_not_of(const StringPiece16& self,
+                        const StringPiece16& s,
+                        size_t pos) {
   if (self.size() == 0)
     return StringPiece::npos;
 
-  for (StringPiece::size_type i = std::min(pos, self.size() - 1); ; --i) {
+  for (size_t self_i = std::min(pos, self.size() - 1); ; --self_i) {
+    bool found = false;
+    for (size_t s_i = 0; s_i < s.size(); s_i++) {
+      if (self.data()[self_i] == s[s_i]) {
+        found = true;
+        break;
+      }
+    }
+    if (!found)
+      return self_i;
+    if (self_i == 0)
+      break;
+  }
+  return StringPiece16::npos;
+}
+
+template<typename STR>
+size_t find_last_not_ofT(const BasicStringPiece<STR>& self,
+                         typename STR::value_type c,
+                         size_t pos) {
+  if (self.size() == 0)
+    return BasicStringPiece<STR>::npos;
+
+  for (size_t i = std::min(pos, self.size() - 1); ; --i) {
     if (self.data()[i] != c)
       return i;
     if (i == 0)
       break;
   }
-  return StringPiece::npos;
+  return BasicStringPiece<STR>::npos;
+}
+
+size_t find_last_not_of(const StringPiece& self,
+                        char c,
+                        size_t pos) {
+  return find_last_not_ofT(self, c, pos);
+}
+
+size_t find_last_not_of(const StringPiece16& self,
+                        char16 c,
+                        size_t pos) {
+  return find_last_not_ofT(self, c, pos);
+}
+
+template<typename STR>
+BasicStringPiece<STR> substrT(const BasicStringPiece<STR>& self,
+                              size_t pos,
+                              size_t n) {
+  if (pos > self.size()) pos = self.size();
+  if (n > self.size() - pos) n = self.size() - pos;
+  return BasicStringPiece<STR>(self.data() + pos, n);
 }
 
 StringPiece substr(const StringPiece& self,
-                   StringPiece::size_type pos,
-                   StringPiece::size_type n) {
-  if (pos > self.size()) pos = self.size();
-  if (n > self.size() - pos) n = self.size() - pos;
-  return StringPiece(self.data() + pos, n);
+                   size_t pos,
+                   size_t n) {
+  return substrT(self, pos, n);
+}
+
+StringPiece16 substr(const StringPiece16& self,
+                     size_t pos,
+                     size_t n) {
+  return substrT(self, pos, n);
 }
 
 }  // namespace internal
 }  // namespace base