| // 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> |
| |
| // Must be last. |
| #include <google/protobuf/port_def.inc> // NOLINT |
| |
| 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<size_t>(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 |
| |
| #include <google/protobuf/port_undef.inc> // NOLINT |
| |
| #endif // GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__ |