/*=========================================================================

  Program:   Insight Segmentation & Registration Toolkit
  Module:    itkSmapsFileParser.cxx
  Language:  C++
  Date:      $Date$
  Version:   $Revision$

  Copyright (c) Insight Software Consortium. All rights reserved.
  See ITKCopyright.txt or http://www.itk.org/HTML/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even 
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 
     PURPOSE.  See the above copyright notices for more information.

=========================================================================*/

#include "itkSmapsFileParser.h"
#include <stdlib.h>

namespace itk
{

bool ITKCommon_EXPORT ci_equal(char a, char b)
{
  return tolower(static_cast<int>(a)) == tolower(static_cast<int>(b));
}

MapRecord::~MapRecord()
{
}

void MapRecord::Reset(void)
{
  m_Tokens.clear();
  m_RecordName = "";
}

/* SmapsRecord implementation */

ITKCommon_EXPORT std::istream&  operator>>(std::istream &in, SmapsRecord &record)
{
  record.Reset();

  try 
    {
    // Get Header line
    std::string headerline;
    std::getline( in, headerline);

    if (headerline.empty())
      {
      return in;
      }

    // Get name
    std::istringstream stream(headerline);
    std::string address, perms, offset, device;  
    int inode=-1;
    // the header is defined with the following expression: "address permissions offset device inode [name]"
    stream>>address;
    if (!stream.good()) itkGenericExceptionMacro( << "bad address: " << address );
    stream>>perms;
    if (!stream.good()) itkGenericExceptionMacro( << "bad perms: " << perms );
    stream>>offset;
    if (!stream.good()) itkGenericExceptionMacro( << "bad offset: " << offset );
    stream>>device;
    if (!stream.good()) itkGenericExceptionMacro( << "bad device: " << device );
    stream>>inode;
    // name can be empty
    if (!stream.eof())
      {
      std::getline(stream, record.m_RecordName);
      }
    
    std::string token;
    std::streampos lastPos = in.tellg();
    // a token is defined with the following expression: "token: N kB" 
    while ( std::getline(in,token,':').good() )
      {
      //make sure it is a token and not a new record. A token doesn't contains space character
      if ( token.find(' ') != std::string::npos )
        {
        in.seekg (lastPos, std::ios::beg);
        break;
        }
      //fill the token with the memory usage N in kB
      in>>record.m_Tokens[token];
      std::getline(in,token);
      if ( token != " kB" || !in.good()) itkGenericExceptionMacro( << "bad size: " << record.m_Tokens[token] );
      lastPos = in.tellg();
      }
    }
  catch (ExceptionObject excp)
    {
    record.Reset();
    // propagate the exception
    itkGenericExceptionMacro( << "The smaps header is corrupted" );
    }
  return in;
}


ITKCommon_EXPORT std::istream& operator>>(std::istream &in, VMMapSummaryRecord &record)
{
  record.Reset();

  try 
    {
    // the record name can have spaces.
    in >> record.m_RecordName;

    if (in.eof() && record.m_RecordName.empty())
      {
      return in;
      }

    if (!in.good()) 
      {
      itkGenericExceptionMacro( << "Bad record name: " << record.m_RecordName );
      }

    std::string bracket;

    while ( (in>>bracket).good() && bracket.find("[",0) == std::string::npos )
      {
      record.m_RecordName += std::string(" ") + bracket;  
      }

    if (!in.good() || bracket.find("[",0) == std::string::npos ) 
      {
      itkGenericExceptionMacro( << "For record: " << record.m_RecordName
                               << ", bad left bracket: " << bracket );
      }

    in >> record.m_Tokens["Size"];

    if( !in.good() ) 
      {
      itkGenericExceptionMacro( << "For record: " << record.m_RecordName
                               << ", bad size: " << record.m_Tokens["Size"] );
      }

    in >> bracket;

    if( !in.good() ) 
      {
      itkGenericExceptionMacro( << "For record: " << record.m_RecordName
                               << ", bad right bracket: " << bracket );
      }
    }
  catch (ExceptionObject excp)
    {
    record.Reset();
    // propagate the exception
    itkGenericExceptionMacro( << "The smaps header is corrupted" );
    }
  return in;
}

/* typical output:
 *  __DATA                             c000 [   4K] rw-/rwx SM=ZER ...l/bin/cronwake
 *  VALLOC_USED(DefaultMallocZone_    25000 [   4K] rw-/rwx SM=COW
 *  MALLOC_USED(DefaultMallocZone_    26000 [  44K] rw-/rwx SM=ZER
 *                                   31000 [   4K] rw-/rwx SM=COW 34300000 00000...
 *                                   32000 [  76K] rw-/rwx SM=COW 00001eaa 01001...
 *                                   45000 [   4K] rw-/rwx SM=COW 34300000 00000...
 *                                   46000 [ 344K] rw-/rwx SM=COW 00000000 00000...
 *  Memory tag=7                     100000 [1044K] rw-/rwx SM=COW
 *  MALLOC_USED(DefaultMallocZone_   300000 [   4K] rw-/rwx SM=PRV
 *  Submap                90000000-9fffffff         r--/r-- machine-wide submap
 *  __DATA                         a0000000 [   4K] rw-/rw- SM=COW ...System.B.dylib
 *  __DATA                         a0001000 [   4K] rw-/rw- SM=ZER ...System.B.dylib
 *  __DATA                         a0002000 [   4K] rw-/rw- SM=COW ...System.B.dylib
 *  __DATA                         a0003000 [  20K] rw-/rw- SM=COW ...System.B.dylib
*/

ITKCommon_EXPORT std::istream& operator>>(std::istream &in, VMMapRecord &record)
{
  record.Reset();
  bool submapFound = false;
  bool recordHasNoName = false;
  char line[256];
  try 
    {
    std::string address;
    do
      {
      // the record name can have spaces.
      in >> record.m_RecordName;
      if( in.eof() || record.m_RecordName.empty() )
        {
        return in;
        }

      if (!in.good())
        {
        itkGenericExceptionMacro( << "Bad record name: " << record.m_RecordName );
        }

      //skip Submap entries
      if ( record.m_RecordName == "Submap" )
        {
        in.getline(line,256);
        submapFound = true;
        }

      // all the records have been parsed, this is a new section
      else if ( record.m_RecordName == "====" )
        {
        record.Reset();
        return in;
        }
      else
        {
        // the name is folowed by an address
        in >> address;

        if( !in.good() )
          {
          itkGenericExceptionMacro( << "For record: " << record.m_RecordName
                                    << ", bad address: " << address );
          }
        // If address is "[" then recordName was the address and there is name for 
        // the record, skip it.
        if ( address.find("[",0) != std::string::npos )
          {
          in.getline(line,256);
          recordHasNoName = true;
          }
        else
          {
          recordHasNoName = false;
          }
        submapFound = false;
        }
      } while(submapFound || recordHasNoName);

    std::string bracket;

    while ( (in>>bracket).good() && bracket.find("[",0) == std::string::npos )
      {
      // the string is not a bracket yet, but probably the address. So the previous
      // address was just the name 
      record.m_RecordName += std::string(" ") + address;
      address = bracket;
      }
    if (!in.good() || bracket.find("[",0) == std::string::npos ) 
      {
      itkGenericExceptionMacro( << "For record: " << record.m_RecordName
                               << ", bad left bracket: " << bracket );
      }
    if ( bracket.length() > 1 )
      {//bracket contains the size, ie "[1024K]"
      record.m_Tokens["Size"] = atoi(bracket.substr(1,bracket.length()-3).c_str());
      }
    else
      {
      in>>record.m_Tokens["Size"];
      }
    if (!in.good()) 
      {
      itkGenericExceptionMacro( << "For record: " << record.m_RecordName
                               << ", bad size: " << record.m_Tokens["Size"] );
      }
    in.getline(line,256);
    if (!in.good()) 
      {
      itkGenericExceptionMacro( << "For record: " << record.m_RecordName
                               << ", bad end of line: " << line );
      }
    }
  catch (ExceptionObject excp)
    {
    record.Reset();
    // propagate the exception
    itkGenericExceptionMacro( << "The smaps header is corrupted" );
    }
  return in;
}


//bool ITKCommon_EXPORT ci_equal(char a, char b); // located in itkSmapsFileParser.cxx

/** Binary functor to accumulate memory usage in kB
 */
template<class TFirstType>
struct MapRecordPlusor{
  MapRecordPlusor<TFirstType>(const char * token = "Size")
    :m_Token(token)
    {
    }

  TFirstType operator()(TFirstType first, const MapRecord* const & second)
    { 
    std::map<std::string,unsigned int>::const_iterator it = second->m_Tokens.find(m_Token);
    return first + ((it!=second->m_Tokens.end())?it->second:0); 
    }
  const char * m_Token;
};

/** Binary functor to accumulate memory usage in kB
 *  The record must match (insensitively) the filter in order to be taken into account
 */
template<class TFirstType>
struct MapRecordConditionalPlusor{  
  MapRecordConditionalPlusor<TFirstType>(const char * filter, const char * token = "Size")
    :m_Filter(filter), m_Token(token)
  {
  }
  TFirstType operator()(TFirstType first, const MapRecord* const &second)
    {
      if ( std::search(second->m_RecordName.begin(),second->m_RecordName.end(),
        m_Filter.begin(),m_Filter.end(),ci_equal) != second->m_RecordName.end())
      {
      return MapRecordPlusor<TFirstType>(m_Token)(first,second);
      }
    return first;
    }
  std::string m_Filter;
  const char * m_Token;
};

/**              ---             MapData               ---              **/

/** MadData destructor */
MapData::~MapData()
{
  this->Reset();
}

MapData::MemoryLoadType 
MapData::GetTotalMemoryUsage( )
{
  return std::accumulate(this->m_Records.begin(), this->m_Records.end(), 0, MapRecordPlusor<MemoryLoadType>());
}

MapData::MemoryLoadType 
MapData::GetMemoryUsage( const char * filter , const char * token)
{
  return std::accumulate(this->m_Records.begin(), this->m_Records.end(), 0, MapRecordConditionalPlusor<MemoryLoadType>(filter,token));
}

/** is the data empty ? */
bool MapData::Empty()
{
  return m_Records.empty();
}

void DeleteMapRecord(MapRecord* const &record)
{
  delete record;
}

void MapData::Reset()
{
  std::for_each(m_Records.begin(),m_Records.end(),DeleteMapRecord);
  m_Records.clear();
}

/**              ---            SmapsData               ---              **/

SmapsData_2_6::~SmapsData_2_6()
{
}

ITK_EXPORT std::istream& operator>>( std::istream & smapsStream, SmapsData_2_6 & data)
{
  SmapsRecord* record = NULL;
  // reset the records from a previous parsing
  data.Reset();
  try
    {
    record = new SmapsRecord;
    // parse each line of the Smaps file and fill the record vector.
    while( smapsStream >> *record )
      {
      data.m_Records.push_back( record );
      record = new SmapsRecord;
      }
    }
  catch( ExceptionObject excp )
    {
    // in case of error, erase the records.
    data.Reset();
    // propagate the exception
    itkGenericExceptionMacro( << "The Smaps stream contains errors, can't read the memory records." );
    }
  delete record;
  return smapsStream;
}

SmapsData_2_6::MemoryLoadType 
SmapsData_2_6::GetHeapUsage()
{
  MemoryLoadType heapUsage = this->GetMemoryUsage("heap","Size");
  // in some machines, there is no [heap] record; 
  if ( heapUsage == 0 )
    {
    //use the unnamed segments instead
    heapUsage = this->GetMemoryUsage("","Size");
    }
  return heapUsage;
}

SmapsData_2_6::MemoryLoadType 
SmapsData_2_6::GetStackUsage()
{
  return this->GetMemoryUsage("stack","Size");
}

/**              ---            VMMapData               ---              **/

VMMapData_10_2
::VMMapData_10_2()
  :m_UsingSummary(false)
{
}

VMMapData_10_2
::~VMMapData_10_2()
{
}


ITK_EXPORT std::istream& operator>>( std::istream & stream, VMMapData_10_2 & data)
{
  MapRecord* record = NULL;
  // reset the records from a previous parsing
  data.Reset();
  try
    {
    std::string line;
    std::streampos startPos = stream.tellg();
    // get to the Summary subsection
    while( std::getline(stream,line).good() )
      {
      if ( line.find("==== Summary for process",0) != std::string::npos )
        break;
      }
    // get to the first record
    while( std::getline(stream,line).good() )
      {
      if ( line.find("REGION TYPE",0) != std::string::npos )
        break;
      }
    // burn the line "===========             [ =======]"
    if ( !std::getline(stream,line).good() )
      {
      //sometimes, vmmap doesn't have any Region Type summary sections, 
      //parse "Writable regions" instead
      //go back to the beginning of the file
      stream.clear();
      stream.seekg(0,std::ios_base::beg);
      // get to the Summary subsection
      while( std::getline(stream,line).good() )
        {
        if ( line.find("==== Writable regions for process",0) != std::string::npos )
          break;
        }
      if ( stream.fail() )
        {
        itkGenericExceptionMacro( << "Can't find the \"Writable regions\" section, can't read the memory records." );
        }
      data.m_UsingSummary = false;
      }
    else
      {
      data.m_UsingSummary = true;
      }
    if( data.m_UsingSummary )
      {
      record = new VMMapSummaryRecord;
      // parse each line of the Smaps file and fill the record vector.
      while( stream >> *dynamic_cast<VMMapSummaryRecord *>(record) )
        {
        if( record->m_RecordName.empty() )
          {
          break;
          }
        data.m_Records.push_back( record );
        record = new VMMapSummaryRecord;
        }
      }
    else
      {
      record = new VMMapRecord;
      // parse each line of the Smaps file and fill the record vector.
      while( stream >> *dynamic_cast<VMMapRecord* >(record) )
        {
        if( record->m_RecordName.empty() )
          {
          break;
          }
        data.m_Records.push_back( record );
        record = new VMMapRecord;
        }
      }
    }
  catch( ExceptionObject excp )
    {
    // in case of error, erase the records.
    data.Reset();
    // propagate the exception
    itkGenericExceptionMacro( << "The VMMap stream contains errors, can't read the memory records." );
    }
  //last record failed, it hasn't be added into data, delete it.
  delete record;
  return stream;
}

VMMapData_10_2::MemoryLoadType 
VMMapData_10_2::GetHeapUsage()
{
  return this->GetMemoryUsage("malloc","Size");
}

VMMapData_10_2::MemoryLoadType 
VMMapData_10_2::GetStackUsage()
{
  return this->GetMemoryUsage("stack","Size");
}


} // end namespace itk