#include "MemoryModel.h"
#include "include/compat.h"
#include "debug.h"
#if defined(__linux__)
#include <malloc.h>
#endif

#include <fstream>

#define dout_subsys ceph_subsys_

using namespace std;

MemoryModel::MemoryModel(CephContext *cct_)
  : cct(cct_)
{
}

void MemoryModel::_sample(snap *psnap)
{
  ifstream f;

  f.open(PROCPREFIX "/proc/self/status");
  if (!f.is_open()) {
    ldout(cct, 0) << "check_memory_usage unable to open " PROCPREFIX "/proc/self/status" << dendl;
    return;
  }
  while (!f.eof()) {
    string line;
    getline(f, line);
    
    if (strncmp(line.c_str(), "VmSize:", 7) == 0)
      psnap->size = atol(line.c_str() + 7);
    else if (strncmp(line.c_str(), "VmRSS:", 6) == 0)
      psnap->rss = atol(line.c_str() + 7);
    else if (strncmp(line.c_str(), "VmHWM:", 6) == 0)
      psnap->hwm = atol(line.c_str() + 7);
    else if (strncmp(line.c_str(), "VmLib:", 6) == 0)
      psnap->lib = atol(line.c_str() + 7);
    else if (strncmp(line.c_str(), "VmPeak:", 7) == 0)
      psnap->peak = atol(line.c_str() + 7);
    else if (strncmp(line.c_str(), "VmData:", 7) == 0)
      psnap->data = atol(line.c_str() + 7);
  }
  f.close();

  f.open(PROCPREFIX "/proc/self/maps");
  if (!f.is_open()) {
    ldout(cct, 0) << "check_memory_usage unable to open " PROCPREFIX "/proc/self/maps" << dendl;
    return;
  }

  long heap = 0;
  while (f.is_open() && !f.eof()) {
    string line;
    getline(f, line);
    //ldout(cct, 0) << "line is " << line << dendl;

    const char *start = line.c_str();
    const char *dash = start;
    while (*dash && *dash != '-') dash++;
    if (!*dash)
      continue;
    const char *end = dash + 1;
    while (*end && *end != ' ') end++;
    if (!*end)
      continue;
    unsigned long long as = strtoll(start, 0, 16);
    unsigned long long ae = strtoll(dash+1, 0, 16);

    //ldout(cct, 0) << std::hex << as << " to " << ae << std::dec << dendl;

    end++;
    const char *mode = end;

    int skip = 4;
    while (skip--) {
      end++;
      while (*end && *end != ' ') end++;
    }
    if (*end)
      end++;

    long size = ae - as;
    //ldout(cct, 0) << "size " << size << " mode is '" << mode << "' end is '" << end << "'" << dendl;

    /*
     * anything 'rw' and anon is assumed to be heap.
     */
    if (mode[0] == 'r' && mode[1] == 'w' && !*end)
      heap += size;
  }

  psnap->heap = heap >> 10;

}
