src/gromacs/utility/inmemoryserializer.cpp

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2016,2017, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   6  * and including many others, as listed in the AUTHORS file in the
   7  * top-level source directory and at http://www.gromacs.org.
   8  *
   9  * GROMACS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
  12  * of the License, or (at your option) any later version.
  13  *
  14  * GROMACS is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with GROMACS; if not, see
  21  * http://www.gnu.org/licenses, or write to the Free Software Foundation,
  22  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
  23  *
  24  * If you want to redistribute modifications to GROMACS, please
  25  * consider that scientific software is very special. Version
  26  * control is crucial - bugs must be traceable. We will be happy to
  27  * consider code for inclusion in the official distribution, but
  28  * derived work must not be called official GROMACS. Details are found
  29  * in the README & COPYING files - if they are missing, get the
  30  * official version at http://www.gromacs.org.
  31  *
  32  * To help us fund GROMACS development, we humbly ask that you cite
  33  * the research papers on the package. Check out http://www.gromacs.org.
  34  */
  35 #include "gmxpre.h"
  36
  37 #include "inmemoryserializer.h"
  38
  39 #include <algorithm>
  40 #include <vector>
  41
  42 #include "gromacs/utility/gmxassert.h"
  43
  44 namespace gmx
  45 {
  46
  47 namespace
  48 {
  49
  50 //! Returns offset to add to `pos` to get it aligned at `alignment` bytes.
  51 size_t alignedOffset(size_t pos, size_t alignment)
  52 {
  53     return (alignment - pos % alignment) % alignment;
  54 }
  55
  56 }   // namespace
  57
  58 /********************************************************************
  59  * InMemorySerializer
  60  */
  61
  62 class InMemorySerializer::Impl
  63 {
  64     public:
  65         template <typename T>
  66         void doValue(T value)
  67         {
  68             // Here, we assume that the vector memory buffer start is aligned,
  69             // similar to what malloc() guarantees.
  70             const size_t size = buffer_.size();
  71             const size_t pos  = size + alignedOffset(size, alignof(T));
  72             buffer_.resize(pos + sizeof(T));
  73             *reinterpret_cast<T *>(&buffer_[pos]) = value;
  74         }
  75         void doString(const std::string &value)
  76         {
  77             doValue<size_t>(value.size());
  78             const size_t pos = buffer_.size();
  79             buffer_.resize(pos + value.size());
  80             std::copy(value.begin(), value.end(), &buffer_[pos]);
  81         }
  82
  83         std::vector<char> buffer_;
  84 };
  85
  86 InMemorySerializer::InMemorySerializer()
  87     : impl_(new Impl)
  88 {
  89 }
  90
  91 InMemorySerializer::~InMemorySerializer()
  92 {
  93 }
  94
  95 std::vector<char> InMemorySerializer::finishAndGetBuffer()
  96 {
  97     return std::move(impl_->buffer_);
  98 }
  99
 100 void InMemorySerializer::doUChar(unsigned char *value)
 101 {
 102     impl_->doValue(*value);
 103 }
 104
 105 void InMemorySerializer::doInt(int *value)
 106 {
 107     impl_->doValue(*value);
 108 }
 109
 110 void InMemorySerializer::doInt64(gmx_int64_t *value)
 111 {
 112     impl_->doValue(*value);
 113 }
 114
 115 void InMemorySerializer::doFloat(float *value)
 116 {
 117     impl_->doValue(*value);
 118 }
 119
 120 void InMemorySerializer::doDouble(double *value)
 121 {
 122     impl_->doValue(*value);
 123 }
 124
 125 void InMemorySerializer::doString(std::string *value)
 126 {
 127     impl_->doString(*value);
 128 }
 129
 130 /********************************************************************
 131  * InMemoryDeserializer
 132  */
 133
 134 class InMemoryDeserializer::Impl
 135 {
 136     public:
 137         explicit Impl(const std::vector<char> &buffer)
 138             : buffer_(buffer), pos_(0)
 139         {
 140         }
 141
 142         template <typename T>
 143         void doValue(T *value)
 144         {
 145             pos_  += alignedOffset(pos_, alignof(T));
 146             *value = *reinterpret_cast<const T *>(&buffer_[pos_]);
 147             pos_  += sizeof(T);
 148         }
 149         void doString(std::string *value)
 150         {
 151             size_t size;
 152             doValue<size_t>(&size);
 153             *value = std::string(&buffer_[pos_], &buffer_[pos_ + size]);
 154             pos_  += size;
 155         }
 156
 157         const std::vector<char> &buffer_;
 158         size_t                   pos_;
 159 };
 160
 161 InMemoryDeserializer::InMemoryDeserializer(const std::vector<char> &buffer)
 162     : impl_(new Impl(buffer))
 163 {
 164 }
 165
 166 InMemoryDeserializer::~InMemoryDeserializer()
 167 {
 168 }
 169
 170 void InMemoryDeserializer::doUChar(unsigned char *value)
 171 {
 172     impl_->doValue(value);
 173 }
 174
 175 void InMemoryDeserializer::doInt(int *value)
 176 {
 177     impl_->doValue(value);
 178 }
 179
 180 void InMemoryDeserializer::doInt64(gmx_int64_t *value)
 181 {
 182     impl_->doValue(value);
 183 }
 184
 185 void InMemoryDeserializer::doFloat(float *value)
 186 {
 187     impl_->doValue(value);
 188 }
 189
 190 void InMemoryDeserializer::doDouble(double *value)
 191 {
 192     impl_->doValue(value);
 193 }
 194
 195 void InMemoryDeserializer::doString(std::string *value)
 196 {
 197     impl_->doString(value);
 198 }
 199
 200 } // namespace gmx