SystemEnvironment.h

/* -*- mode: c++; indent-tabs-mode: nil -*- */
/*
  SystemEnvironment.h

  Qore Programming Language

  Copyright (C) 2003 - 2014 David Nichols

  Permission is hereby granted, free of charge, to any person obtaining a
  copy of this software and associated documentation files (the "Software"),
  to deal in the Software without restriction, including without limitation
  the rights to use, copy, modify, merge, publish, distribute, sublicense,
  and/or sell copies of the Software, and to permit persons to whom the
  Software is furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  DEALINGS IN THE SOFTWARE.

  Note that the Qore library is released under a choice of three open-source
  licenses: MIT (as above), LGPL 2+, or GPL 2+; see README-LICENSE for more
  information.
*/

#ifndef _QORE_SYSTEMENVIRONMENT_H

#define _QORE_SYSTEMENVIRONMENT_H


class SystemEnvironment {
      friend class AtomicEnvironmentSetter;

   private:
      DLLLOCAL SystemEnvironment(const SystemEnvironment&);

      DLLLOCAL SystemEnvironment& operator=(const SystemEnvironment&);

   protected:

      DLLLOCAL static int set_intern(const char *name, const char *value, bool overwrite = 1);


      DLLLOCAL static class QoreString *get_intern(const char *name);


      DLLLOCAL static class QoreStringNode *get_as_string_node_intern(const char *name);


      DLLLOCAL static int get_intern(const char *name, class QoreString &str);
      

      DLLLOCAL static int unset_intern(const char *name);
      
   public:
      DLLLOCAL SystemEnvironment();
      DLLLOCAL ~SystemEnvironment();


      DLLEXPORT static int set(const char *name, const char *value, bool overwrite = 1);


      DLLEXPORT static class QoreString *get(const char *name);


      DLLEXPORT static class QoreStringNode *getAsStringNode(const char *name);


      DLLEXPORT static int get(const char *name, class QoreString &str);
      

      DLLEXPORT static int unset(const char *name);
      

      DLLEXPORT static bool valueExists(const char* name); // true if exists and is not empty
};

DLLEXPORT extern SystemEnvironment SysEnv;


class AtomicEnvironmentSetter
{
   private:
      DLLLOCAL AtomicEnvironmentSetter(const AtomicEnvironmentSetter&);

      DLLLOCAL AtomicEnvironmentSetter& operator=(const AtomicEnvironmentSetter&);

      DLLLOCAL void* operator new(size_t); // not implemented, make sure it is not new'ed

   public:
      DLLEXPORT AtomicEnvironmentSetter();
      DLLEXPORT ~AtomicEnvironmentSetter();


      DLLEXPORT int set(const char *name, const char *value, bool overwrite = 1);


      DLLEXPORT class QoreString *get(const char *name);


      DLLEXPORT class QoreStringNode *getAsStringNode(const char *name);


      DLLEXPORT int get(const char *name, class QoreString &str);
      

      DLLEXPORT int unset(const char *name);
      

      DLLEXPORT bool valueExists(const char* name); // true if exists and is not empty
};

#endif