Skip to Navigation

User login

Username: *

Password: *

• Request new password

• jigdo
• Development
• Debian jigdo mini-HOWTO

Home › jigdo › Development › jigdo API

jigdo API

Last update by Admin on 2010-05-23

• Namespaces
• Class hierarchy
• Class list
• File list
• Namespace Members
• Class Members
• File Members

cachefile.hh

Go to the documentation of this file.

/* $Id: cachefile.hh,v 1.10 2003/03/03 20:47:16 richard Exp $ -*- C++ -*-
  __   _
  |_) /|  Copyright (C) 2001-2002  |  richard@
  | \/¯|  Richard Atterer          |  atterer.net
  ¯ '` ¯
  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License, version 2. See
  the file COPYING for details.

*/

#ifndef CACHEFILE_HH
#define CACHEFILE_HH

#include <config.h>

#include <string>
#include <time.h> /* for time_t */

#if HAVE_LIBDB
#include <db.h>
#include <stdlib.h> /* free() */
#include <string.h> /* memcpy(), memset() */

#include <debug.hh>
#include <status.hh>
//______________________________________________________________________

struct DbError : public Error {
  explicit DbError(int c) : Error(db_strerror(c)), code(c) { }
  DbError(int c, const string& m) : Error(m), code(c) { }
  DbError(int c, const char* m) : Error(m), code(c) { }
  int code;
};
//______________________________________________________________________

class CacheFile {
public:
  CacheFile(const char* dbName);
  inline ~CacheFile();

  Status find(const byte*& resultData, size_t& resultSize,
              const string& fileName, uint64 fileSize, time_t mtime);

  Status findName(const byte*& resultData, size_t& resultSize,
                  const string& fileName,
                  off_t& resultFileSize, time_t& resultMtime);

  inline void insert(const byte* inData, size_t inSize,
                     const string& fileName, time_t mtime, uint64 fileSize);
  template<class Functor>
  inline void insert(Functor f, size_t inSize, const string& fileName,
                     time_t mtime, uint64 fileSize);

  void expire(time_t t);

private:
  // Don't copy
  explicit inline CacheFile(const CacheFile&);
  inline CacheFile& operator=(const CacheFile&);
  byte* insert_prepare(size_t inSize);
  void insert_perform(const string& fileName, time_t mtime, uint64 fileSize);

  /* Byte offsets of first members of a cache entry (see start of this
     file). Defining a struct with byte members would be more
     convenient, but would also be a recipe for disaster because of
     alignment problems. (E.g., a RISC machine might pad to the next
     multiple of 4 bytes after every byte member.) */
  enum { ACCESS = 0, MTIME = 4, SIZE = 8, USER_DATA = 14 };

  DB* db; // Database object
  DBT data; // Object for result data
};
//______________________________________________________________________

CacheFile::~CacheFile() {
  free(data.data);
  Paranoid(db != 0);
  db->close(db, 0); // no flags, ignore any errors
}
//______________________________________________________________________

void CacheFile::insert(const byte* inData, size_t inSize,
    const string& fileName, time_t mtime, uint64 fileSize) {
  memcpy(insert_prepare(inSize), inData, inSize);
  insert_perform(fileName, mtime, fileSize);
}

template<class Functor>
void CacheFile::insert(Functor f, size_t inSize, const string& fileName,
                       time_t mtime, uint64 fileSize) {
  f(insert_prepare(inSize));
  insert_perform(fileName, mtime, fileSize);
}

//======================================================================

#else

// !HAVE_LIBDB - provide a dummy implementation which does nothing

class CacheFile {
public:
  CacheFile(const char*) { }
  ~CacheFile() { }
  bool find(const byte*&, size_t&, const string&, time_t, uint64) {
    return false;
  }
  bool find_name(const byte*&, size_t&, const string&,
                 long long int&, time_t&) {
    return false;
  }
  template<class Functor>
  void insert(Functor, size_t, const string&, time_t, uint64) { }
  void insert(const byte*, size_t, const string&, time_t, uint64) { }
  void expire(time_t) { }
};

#endif
#endif

---

• Photography
• Software
• jigdo
• Research
• About

© Copyright 2014 Richard Atterer

 Top of page  •  Home  •  Sitemap  •  Contact  •  About