/*
   Bacula® - The Network Backup Solution

   Copyright (C) 2003-2007 Free Software Foundation Europe e.V.

   The main author of Bacula is Kern Sibbald, with contributions from
   many others, a complete list can be found in the file AUTHORS.
   This program is Free Software; you can redistribute it and/or
   modify it under the terms of version two of the GNU General Public
   License as published by the Free Software Foundation and included
   in the file LICENSE.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   02110-1301, USA.

   Bacula® is a registered trademark of John Walker.
   The licensor of Bacula is the Free Software Foundation Europe
   (FSFE), Fiduciary Program, Sumatrastrasse 25, 8006 Zürich,
   Switzerland, email:ftf@fsfeurope.org.
*/
/*
 *   Version $Id: alist.h 4992 2007-06-07 14:46:43Z kerns $
 *
 *  Kern Sibbald, June MMIII
 */


/*
 * There is a lot of extra casting here to work around the fact
 * that some compilers (Sun and Visual C++) do not accept
 * (void *) as an lvalue on the left side of an equal.
 *
 * Loop var through each member of list
 */
#ifdef HAVE_TYPEOF
#define foreach_alist(var, list) \
        for((var)=(typeof(var))(list)->first(); (var); (var)=(typeof(var))(list)->next() )
#else
#define foreach_alist(var, list) \
    for((*((void **)&(var))=(void*)((list)->first())); \
         (var); \
         (*((void **)&(var))=(void*)((list)->next())))
#endif



/* Second arg of init */
enum {
  owned_by_alist = true,
  not_owned_by_alist = false
};

/*
 * Array list -- much like a simplified STL vector
 *   array of pointers to inserted items
 */
class alist : public SMARTALLOC {
   void **items;
   int num_items;
   int max_items;
   int num_grow;
   int cur_item;
   bool own_items;
   void grow_list(void);
public:
   alist(int num = 1, bool own=true);
   ~alist();
   void init(int num = 1, bool own=true);
   void append(void *item);
   void prepend(void *item);
   void *remove(int index);
   void *get(int index);
   bool empty() const;
   void *prev();
   void *next();
   void *first();
   void *last();
   void * operator [](int index) const;
   int size() const;
   void destroy();
   void grow(int num);

   /* Use it as a stack, pushing and poping from the end */
   void push(void *item) { append(item); };
   void *pop() { return remove(num_items-1); };
};

inline void * alist::operator [](int index) const {
   if (index < 0 || index >= num_items) {
      return NULL;
   }
   return items[index];
}

inline bool alist::empty() const
{
   /* Check for null pointer */
   return this ? num_items == 0 : true;
}

/*
 * This allows us to do explicit initialization,
 *   allowing us to mix C++ classes inside malloc'ed
 *   C structures. Define before called in constructor.
 */
inline void alist::init(int num, bool own) {
   items = NULL;
   num_items = 0;
   max_items = 0;
   num_grow = num;
   own_items = own;
}

/* Constructor */
inline alist::alist(int num, bool own) {
   init(num, own);
}

/* Destructor */
inline alist::~alist() {
   destroy();
}



/* Current size of list */
inline int alist::size() const
{
   /*
    * Check for null pointer, which allows test
    *  on size to succeed even if nothing put in
    *  alist.
    */
   return this ? num_items : 0;
}

/* How much to grow by each time */
inline void alist::grow(int num)
{
   num_grow = num;
}