From b55a20fa2c669b181f47ea9219b8e74d1263da19 Mon Sep 17 00:00:00 2001 From: "xiaofeng@google.com" Date: Sat, 22 Sep 2012 02:40:50 +0000 Subject: Down-integrate from internal branch --- src/google/protobuf/stubs/stl_util.h | 121 +++++++++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) create mode 100644 src/google/protobuf/stubs/stl_util.h (limited to 'src/google/protobuf/stubs/stl_util.h') diff --git a/src/google/protobuf/stubs/stl_util.h b/src/google/protobuf/stubs/stl_util.h new file mode 100644 index 00000000..9021dada --- /dev/null +++ b/src/google/protobuf/stubs/stl_util.h @@ -0,0 +1,121 @@ +// 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 + +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 +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(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 +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 +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__ -- cgit v1.2.3