src/storage/Mempool.cpp

   1 /** Aesalon, a tool to visualize program behaviour in real time.
   2         Copyright (C) 2009-2011, Aesalon development team.
   3
   4         Aesalon is distributed under the terms of the GNU GPLv3. See
   5         the included file LICENSE for more information.
   6
   7         @file src/storage/Mempool.cpp
   8 */
   9
  10 #include <sys/mman.h>
  11 #include <errno.h>
  12 #include <cstring>
  13
  14 #include "storage/Mempool.h"
  15 #include "util/MessageSystem.h"
  16
  17 namespace Storage {
  18
  19 Mempool::Mempool() {
  20
  21 }
  22
  23 Mempool::~Mempool() {
  24
  25 }
  26
  27 void *Mempool::request(uint32_t size) {
  28         int pools = m_mapVector.size();
  29         int pool;
  30         for(pool = 0; pool < pools; pool ++) {
  31                 if(m_useVector[pool] + size <= m_mempoolSize) break;
  32         }
  33
  34         if(pool == pools) createNew();
  35
  36         m_useVector[pool] += size;
  37
  38         return (m_mapVector[pool] + m_useVector[pool] - size);
  39 }
  40
  41 void Mempool::createNew() {
  42         void *memory = mmap(NULL, m_mempoolSize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
  43         if(memory == MAP_FAILED) {
  44                 Message(Fatal, "Could not create memory mapping: " << std::strerror(errno));
  45         }
  46         m_mapVector.push_back(static_cast<uint8_t *>(memory));
  47         m_useVector.push_back(0);
  48 }
  49
  50 } // namespace Storage