Update protobuf to r428, part 1.

third_party/protobuf/src/google/protobuf/stubs/stl_util.h

+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// 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.
+
+// from google3/util/gtl/stl_util.h
+
+#ifndef GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__
+#define GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__
+
+#include <google/protobuf/stubs/common.h>
+
+namespace google {
+namespace protobuf {
+
+// STLDeleteContainerPointers()
+//  For a range within a container of pointers, calls delete
+//  (non-array version) on these pointers.
+// NOTE: for these three functions, we could just implement a DeleteObject
+// functor and then call for_each() on the range and functor, but this
+// requires us to pull in all of algorithm.h, which seems expensive.
+// For hash_[multi]set, it is important that this deletes behind the iterator
+// because the hash_set may call the hash function on the iterator when it is
+// advanced, which could result in the hash function trying to deference a
+// stale pointer.
+template <class ForwardIterator>
+void STLDeleteContainerPointers(ForwardIterator begin,
+                                ForwardIterator end) {
+  while (begin != end) {
+    ForwardIterator temp = begin;
+    ++begin;
+    delete *temp;
+  }
+}
+
+// Inside Google, this function implements a horrible, disgusting hack in which
+// we reach into the string's private implementation and resize it without
+// initializing the new bytes.  In some cases doing this can significantly
+// improve performance.  However, since it's totally non-portable it has no
+// place in open source code.  Feel free to fill this function in with your
+// own disgusting hack if you want the perf boost.
+inline void STLStringResizeUninitialized(string* s, size_t new_size) {
+  s->resize(new_size);
+}
+
+// Return a mutable char* pointing to a string's internal buffer,
+// which may not be null-terminated. Writing through this pointer will
+// modify the string.
+//
+// string_as_array(&str)[i] is valid for 0 <= i < str.size() until the
+// next call to a string method that invalidates iterators.
+//
+// As of 2006-04, there is no standard-blessed way of getting a
+// mutable reference to a string's internal buffer. However, issue 530
+// (http://www.open-std.org/JTC1/SC22/WG21/docs/lwg-active.html#530)
+// proposes this as the method. According to Matt Austern, this should
+// already work on all current implementations.
+inline char* string_as_array(string* str) {
+  // DO NOT USE const_cast<char*>(str->data())! See the unittest for why.
+  return str->empty() ? NULL : &*str->begin();
+}
+
+// STLDeleteElements() deletes all the elements in an STL container and clears
+// the container.  This function is suitable for use with a vector, set,
+// hash_set, or any other STL container which defines sensible begin(), end(),
+// and clear() methods.
+//
+// If container is NULL, this function is a no-op.
+//
+// As an alternative to calling STLDeleteElements() directly, consider
+// ElementDeleter (defined below), which ensures that your container's elements
+// are deleted when the ElementDeleter goes out of scope.
+template <class T>
+void STLDeleteElements(T *container) {
+  if (!container) return;
+  STLDeleteContainerPointers(container->begin(), container->end());
+  container->clear();
+}
+
+// Given an STL container consisting of (key, value) pairs, STLDeleteValues
+// deletes all the "value" components and clears the container.  Does nothing
+// in the case it's given a NULL pointer.
+
+template <class T>
+void STLDeleteValues(T *v) {
+  if (!v) return;
+  for (typename T::iterator i = v->begin(); i != v->end(); ++i) {
+    delete i->second;
+  }
+  v->clear();
+}
+
+}  // namespace protobuf
+}  // namespace google
+
+#endif  // GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__