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- // Protocol Buffers - Google's data interchange format
- // Copyright 2008 Google Inc. All rights reserved.
- // https://developers.google.com/protocol-buffers/
- //
- // 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>
- #include <algorithm>
- namespace google {
- namespace protobuf {
- // 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(std::string* s, size_t new_size) {
- s->resize(new_size);
- }
- // As above, but we make sure to follow amortized growth in which we always
- // increase the capacity by at least a constant factor >1.
- inline void STLStringResizeUninitializedAmortized(std::string* s,
- size_t new_size) {
- const size_t cap = s->capacity();
- if (new_size > cap) {
- // Make sure to always grow by at least a factor of 2x.
- s->reserve(std::max(new_size, 2 * cap));
- }
- STLStringResizeUninitialized(s, 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(std::string* str) {
- // DO NOT USE const_cast<char*>(str->data())! See the unittest for why.
- return str->empty() ? nullptr : &*str->begin();
- }
- } // namespace protobuf
- } // namespace google
- #endif // GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__
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