/*

 * Copyright (c) 2007, Novell Inc.

 *

 * This program is licensed under the BSD license, read LICENSE.BSD

 * for further information

 */

#ifndef LIBSOLV_DIRPOOL_H

#define LIBSOLV_DIRPOOL_H

#include "pooltypes.h"

#include "util.h"

#ifdef __cplusplus

extern "C" {

#endif

typedef struct s_Dirpool {

  Id *dirs;

  int ndirs;

  Id *dirtraverse;

} Dirpool;

void dirpool_init(Dirpool *dp);

void dirpool_free(Dirpool *dp);

void dirpool_make_dirtraverse(Dirpool *dp);

Id dirpool_add_dir(Dirpool *dp, Id parent, Id comp, int create);

/* return the parent directory of child did */

static inline Id dirpool_parent(Dirpool *dp, Id did)

{

  if (!did)

    return 0;

  while (dp->dirs[--did] > 0)

    ;

  return -dp->dirs[did];

}

/* return the next child entry of child did */

static inline Id

dirpool_sibling(Dirpool *dp, Id did)

{

  /* if this block contains another entry, simply return it */

  if (did + 1 < dp->ndirs && dp->dirs[did + 1] > 0)

    return did + 1;

  /* end of block reached, rewind to get to the block's

   * dirtraverse entry */

  while (dp->dirs[--did] > 0)

    ;

  /* need to special case did == 0 to prevent looping */

  if (!did)

    return 0;

  if (!dp->dirtraverse)

    dirpool_make_dirtraverse(dp);

  return dp->dirtraverse[did];

}

/* return the first child entry of directory did */

static inline Id

dirpool_child(Dirpool *dp, Id did)

{

  if (!dp->dirtraverse)

    dirpool_make_dirtraverse(dp);

  return dp->dirtraverse[did];

}

static inline void

dirpool_free_dirtraverse(Dirpool *dp)

{

  solv_free(dp->dirtraverse);

  dp->dirtraverse = 0;

}

static inline Id

dirpool_compid(Dirpool *dp, Id did)

{

  return dp->dirs[did];

}

#ifdef __cplusplus

}

#endif

#endif /* LIBSOLV_DIRPOOL_H */