source: tags/0.5/files_pool.cpp @ 9

#include "files_pool.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include "wutils.h"
#include <string.h>
#include <strings.h>
#include <stdio.h>
#include <algorithm>
#include <fstream>
#include "stopos.h"

// constructor
files_pool::files_pool()
{
  this->dir_suffix = "_stopos_files_dir";
}

// own version of set_db_name.
// this will be a directory, and on creation
// it will be recursively removed.
// to avoid oopses, a special name is formed from the input
void files_pool::set_db_name(std::string filename)
{
  this->sdb_name = filename + this->dir_suffix;
  this->db_name  = strdup(sdb_name.c_str());
}

void files_pool::create_fname(std::string &fname,const stopos_key &k)
{
  fname = this->sdb_name + "/" + k.str();
}

int files_pool::get_record(datarecord &r, const stopos_key &k)
{
  std::string fname;
  this->create_fname(fname,k);
  std::ifstream f;
  f.open(fname.c_str(),std::fstream::in);
  if (f.fail())
    return FETCHERROR;

  char b[this->reclen];

  f.getline(b,this->reclen);
  if (f.bad())
    return FETCHERROR;

  r = datarecord(b,dbsep);

  f.close();

  return 0;
}

int files_pool::put_record(datarecord &r, const stopos_key &k)
{
  std::string fname;

  this->create_fname(fname,k);

  std::ofstream f;
  f.open(fname.c_str(),std::fstream::out);
  if (f.fail())
    return STOREERROR;

  std::string buf;

  buf = r.str(dbsep);

  buf.resize(reclen);

  f.write(buf.c_str(),this->reclen);
  if (f.bad())
    return STOREERROR;

  f.close();
  return 0;
}

int files_pool::remove_record(const stopos_key &k)
{
  int rc;
  std::string fname;
  this->create_fname(fname,k);
  rc = unlink(fname.c_str());
  if (rc == -1)
    return this->REMOVEERROR;

  return 0;
}

int files_pool::get_status(void)
{
  std::string fname;
  this->create_fname(fname,this->statuskey);

  std::ifstream f;
  f.open(fname.c_str(),std::fstream::in);
  if (f.fail())
    return FETCHERROR;

  char b[this->reclen];

  f.getline(b,this->reclen);
  if (f.bad())
    return FETCHERROR;

  this->status = statusrecord(b,dbsep);

  return 0;
}

int files_pool::put_status(void)
{
  std::string buf;
  buf = this->status.str(dbsep);

  if (buf.size() > this->reclen)
    return this->STATUSTOOLONG;

  buf.resize(reclen);

  std::string fname;
  this->create_fname(fname,this->statuskey);

  std::ofstream f;
  f.open(fname.c_str(),std::fstream::out);
  if (f.fail())
    return STOREERROR;

  f.write(buf.c_str(),this->reclen);
  if (f.bad())
    return STOREERROR;

  f.close();

  return 0;
}

int files_pool::create_db(void)
{
  int rc;
  rc = this->purge_db();
  if (rc != 0)
    return rc;

  rc = mkdir_p(this->db_name,0755);
  if (rc != 0)
    return rc;

  status.init();


  rc = this->open_db();
  if (rc != 0)
    return rc;

  rc = put_status();
  if (rc != 0)
  {
    this->close_db();
    return this->STOREERROR;
  }

  this->close_db();

  return 0;
}

int files_pool::purge_db(void)
{
  if (this->db_name == 0)
    return NOFILENAME;

  if ( strstr(this->db_name,"_stopos_files_dir") == 0)
    return NOTDIR;

  std::string command;
  command = "rm -rf " + this->sdb_name;
  int rc = system(command.c_str());
  if (rc != 0)
    ;
  return 0;
}

int files_pool::open_db(void)
{
  if (this->db_name == 0)
    return NOFILENAME;

  if (this->db_open)
    return 0;

  // create lockfilename
  this->lockfilename = this->sdb_name+"/lockfile";

  int rc = access(this->db_name,R_OK|W_OK);
  if (rc == -1)
    return OPENERROR;

  struct stat status;
  stat(this->db_name, &status );

  if ( !(status.st_mode & S_IFDIR) )
     return OPENERROR;

  this->lockfile = open(this->lockfilename.c_str(),O_CREAT|O_RDWR,0600);
  if (this->lockfile < 0)
    return LOCKERROR;

  struct flock lock;
  lock.l_type = F_RDLCK|F_WRLCK;
  lock.l_whence = SEEK_SET;
  lock.l_start  = 0;
  lock.l_len    = 0;

  rc = fcntl(this->lockfile,F_SETLKW,&lock);
  if (rc < 0)
    return LOCKERROR;

  this->db_open = 1;

  return 0;
}

int files_pool::close_db(void)
{
  if (!this->db_open)
    return 0;

  struct flock lock;
  lock.l_type = F_UNLCK;
  lock.l_whence = SEEK_SET;
  lock.l_start  = 0;
  lock.l_len    = 0;

  int rc = fcntl(this->lockfile,F_SETLKW,&lock);
  if (rc < 0)
    return UNLOCKERROR;

  close(this->lockfile);

  this->db_open = 0;

  return 0;
}

void files_pool::dump_db(void)
{
  std::string command;
  command ="(for i in ";
  command += db_name;
  command += "/* ; do echo -n `basename $i`:;cat $i | tr -d '\\0' ; echo ; done |sort -n ) 1>&2";
  int rc = system(command.c_str());
  if (rc)
    ;
}