/**
 * @file
 *
 * @ingroup ClassicChains
 *
 * @brief Chain API.
 */
 
/*
 *  Copyright (c) 2010 embedded brains GmbH.
 *
 *  COPYRIGHT (c) 1989-2008.
 *  On-Line Applications Research Corporation (OAR).
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.com/license/LICENSE.
 *
 *  $Id$
 */

#ifndef _RTEMS_CHAIN_H
# error "Never use <rtems/chain.inl> directly; include <rtems/chain.h> instead."
#endif

#ifndef _RTEMS_CHAIN_INL
#define _RTEMS_CHAIN_INL

#include <rtems/score/chain.inl>

/**
 * @addtogroup ClassicChains
 *
 * @{
 */

/**
 *  @brief Initialize a Chain Header
 *
 *  This routine initializes @a the_chain structure to manage the
 *  contiguous array of @a number_nodes nodes which starts at
 *  @a starting_address.  Each node is of @a node_size bytes.
 *
 *  @param[in] the_chain specifies the chain to initialize
 *  @param[in] starting_address is the starting address of the array
 *         of elements
 *  @param[in] number_nodes is the number of nodes that will be in the chain
 *  @param[in] node_size is the size of each node
 */
RTEMS_INLINE_ROUTINE void rtems_chain_initialize(
  rtems_chain_control *the_chain,
  void                *starting_address,
  size_t               number_nodes,
  size_t               node_size
)
{
  _Chain_Initialize( the_chain, starting_address, number_nodes, node_size );
}

/**
 *  @brief Initialize this Chain as Empty
 *
 *  This routine initializes the specified chain to contain zero nodes.
 *
 *  @param[in] the_chain is the chain to be initialized.
 */
RTEMS_INLINE_ROUTINE void rtems_chain_initialize_empty(
  rtems_chain_control *the_chain
)
{
  _Chain_Initialize_empty( the_chain );
}

/**
 *  @brief Set off chain
 *
 *  This function sets the next and previous fields of the @a node to NULL
 *  indicating the @a node is not part of a chain.
 *
 *  @param[in] node the node set to off chain.
 */
RTEMS_INLINE_ROUTINE void rtems_chain_set_off_chain(
  rtems_chain_node *node
)
{
  _Chain_Set_off_chain( node );
}

/**
 *  @brief Is the Node off Chain
 *
 *  This function returns true if the @a node is not on a chain. A @a node is
 *  off chain if the next and previous fields are set to NULL.
 *
 *  @param[in] node is the node off chain.
 *
 *  @return This function returns true if the @a node is off chain.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_is_node_off_chain(
  const rtems_chain_node *node
)
{
  return _Chain_Is_node_off_chain( node );
}

/**
 *  @brief Is the Chain Node Pointer NULL
 *
 *  This function returns true if the_node is NULL and false otherwise.
 *
 *  @param[in] the_node is the node pointer to check.
 *
 *  @return This method returns true if the_node is NULL and false otherwise.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_is_null_node(
  const rtems_chain_node *the_node
)
{
  return _Chain_Is_null_node( the_node );
}

/**
 *  @brief Return pointer to Chain Head
 *
 *  This function returns a pointer to the first node on the chain.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *
 *  @return This method returns the permanent  node of the chain.
 */
RTEMS_INLINE_ROUTINE rtems_chain_node *rtems_chain_head(
  rtems_chain_control *the_chain
)
{
  return _Chain_Head( the_chain );
}

/**
 *  @brief Return pointer to Chain Tail
 *
 *  This function returns a pointer to the last node on the chain.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *
 *  @return This method returns the permanent tail node of the chain.
 */
RTEMS_INLINE_ROUTINE rtems_chain_node *rtems_chain_tail(
  rtems_chain_control *the_chain
)
{
  return _Chain_Tail( the_chain );
}

/**
 *  @brief Return pointer to Chain's First node after the permanent head.
 *
 *  This function returns a pointer to the first node on the chain after the
 *  head.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *
 *  @return This method returns the first node of the chain.
 */
RTEMS_INLINE_ROUTINE rtems_chain_node *rtems_chain_first(
  rtems_chain_control *the_chain
)
{
  return _Chain_First( the_chain );
}

/**
 *  @brief Return pointer to Chain's Last node before the permanent tail.
 *
 *  This function returns a pointer to the last node on the chain just before
 *  the tail.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *
 *  @return This method returns the last node of the chain.
 */
RTEMS_INLINE_ROUTINE rtems_chain_node *rtems_chain_last(
  rtems_chain_control *the_chain
)
{
  return _Chain_Last( the_chain );
}

/**
 *  @brief Return pointer the next node from this node
 *
 *  This function returns a pointer to the next node after this node.
 *
 *  @param[in] the_node is the node to be operated upon.
 *
 *  @return This method returns the next node on the chain.
 */
RTEMS_INLINE_ROUTINE rtems_chain_node *rtems_chain_next(
  rtems_chain_node *the_node
)
{
  return _Chain_Next( the_node );
}

/**
 *  @brief Return pointer the previous node from this node
 *
 *  This function returns a pointer to the previous node on this chain.
 *
 *  @param[in] the_node is the node to be operated upon.
 *
 *  @return This method returns the previous node on the chain.
 */
RTEMS_INLINE_ROUTINE rtems_chain_node *rtems_chain_previous(
  rtems_chain_node *the_node
)
{
  return _Chain_Previous( the_node );
}

/**
 *  @brief Are Two Nodes Equal
 *
 *  This function returns true if @a left and @a right are equal,
 *  and false otherwise.
 *
 *  @param[in] left is the node on the left hand side of the comparison.
 *  @param[in] right is the node on the left hand side of the comparison.
 *
 *  @return This function returns true if @a left and @a right are equal,
 *          and false otherwise.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_are_nodes_equal(
  const rtems_chain_node *left,
  const rtems_chain_node *right
)
{
  return _Chain_Are_nodes_equal( left, right );
}

/**
 *  @brief Is the Chain Empty
 *
 *  This function returns true if there a no nodes on @a the_chain and
 *  false otherwise.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *
 *  @return This function returns true if there a no nodes on @a the_chain and
 *  false otherwise.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_is_empty(
  rtems_chain_control *the_chain
)
{
  return _Chain_Is_empty( the_chain );
}

/**
 *  @brief Is this the First Node on the Chain
 *
 *  This function returns true if the_node is the first node on a chain and
 *  false otherwise.
 *
 *  @param[in] the_node is the node the caller wants to know if it is
 *             the first node on a chain.
 *
 *  @return This function returns true if @a the_node is the first node on
 *          a chain and false otherwise.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_is_first(
  const rtems_chain_node *the_node
)
{
  return _Chain_Is_first( the_node );
}

/**
 *  @brief Is this the Last Node on the Chain
 *
 *  This function returns true if @a the_node is the last node on a chain and
 *  false otherwise.
 *
 *  @param[in] the_node is the node to check as the last node.
 *
 *  @return This function returns true if @a the_node is the last node on
 *          a chain and false otherwise.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_is_last(
  const rtems_chain_node *the_node
)
{
  return _Chain_Is_last( the_node );
}

/**
 *  @brief Does this Chain have only One Node
 *
 *  This function returns true if there is only one node on @a the_chain and
 *  false otherwise.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *
 *  @return This function returns true if there is only one node on
 *          @a the_chain and false otherwise.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_has_only_one_node(
  const rtems_chain_control *the_chain
)
{
  return _Chain_Has_only_one_node( the_chain );
}

/**
 *  @brief Is this Node the Chain Head
 *
 *  This function returns true if @a the_node is the head of the_chain and
 *  false otherwise.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *  @param[in] the_node is the node to check for being the Chain Head.
 *
 *  @return This function returns true if @a the_node is the head of
 *          @a the_chain and false otherwise.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_is_head(
  rtems_chain_control    *the_chain,
  const rtems_chain_node *the_node
)
{
  return _Chain_Is_head( the_chain, the_node );
}

/**
 *  @brief Is this Node the Chail Tail
 *
 *  This function returns true if the_node is the tail of the_chain and
 *  false otherwise.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *  @param[in] the_node is the node to check for being the Chain Tail.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_is_tail(
  rtems_chain_control    *the_chain,
  const rtems_chain_node *the_node
)
{
  return _Chain_Is_tail( the_chain, the_node );
}

/**
 *  @brief Extract the specified node from a chain
 *
 *  This routine extracts @a the_node from the chain on which it resides.
 *  It disables interrupts to ensure the atomicity of the
 *  extract operation.
 *
 *  @arg the_node specifies the node to extract
 */
RTEMS_INLINE_ROUTINE void rtems_chain_extract(
  rtems_chain_node *the_node
)
{
  _Chain_Extract( the_node );
}

/**
 *  @brief Extract the specified node from a chain (unprotected).
 *
 *  This routine extracts @a the_node from the chain on which it resides.
 *
 *  @note It does NOT disable interrupts to ensure the atomicity of the
 *  append operation.
 */
RTEMS_INLINE_ROUTINE void rtems_chain_extract_unprotected(
  rtems_chain_node *the_node
)
{
  _Chain_Extract_unprotected( the_node );
}

/**
 *  @brief Obtain the first node on a chain
 *
 *  This function removes the first node from @a the_chain and returns
 *  a pointer to that node.  If @a the_chain is empty, then NULL is returned.
 *
 *  @return This method returns a pointer a node.  If a node was removed,
 *          then a pointer to that node is returned.  If @a the_chain was
 *          empty, then NULL is returned.
 *
 *  @note It disables interrupts to ensure the atomicity of the get operation.
 */
RTEMS_INLINE_ROUTINE rtems_chain_node *rtems_chain_get(
  rtems_chain_control *the_chain
)
{
  return _Chain_Get( the_chain );
}

/**
 * @brief See _Chain_Get_unprotected().
 */
RTEMS_INLINE_ROUTINE rtems_chain_node *rtems_chain_get_unprotected(
  rtems_chain_control *the_chain
)
{
  return _Chain_Get_unprotected( the_chain );
}

/**
 *  @brief Insert a node on a chain
 *
 *  This routine inserts @a the_node on a chain immediately following
 *  @a after_node.  
 *
 *  @note It disables interrupts to ensure the atomicity
 *  of the extract operation.
 */
RTEMS_INLINE_ROUTINE void rtems_chain_insert(
  rtems_chain_node *after_node,
  rtems_chain_node *the_node
)
{
  _Chain_Insert( after_node, the_node );
}

/**
 * @brief See _Chain_Insert_unprotected().
 */
RTEMS_INLINE_ROUTINE void rtems_chain_insert_unprotected(
  rtems_chain_node *after_node,
  rtems_chain_node *the_node
)
{
  _Chain_Insert_unprotected( after_node, the_node );
}

/**
 *  @brief Append a node on the end of a chain
 *
 *  This routine appends @a the_node onto the end of @a the_chain.
 *
 *  @note It disables interrupts to ensure the atomicity of the
 *  append operation.
 */
RTEMS_INLINE_ROUTINE void rtems_chain_append(
  rtems_chain_control *the_chain,
  rtems_chain_node    *the_node
)
{
  _Chain_Append( the_chain, the_node );
}

/**
 *  @brief Append a node on the end of a chain (unprotected)
 *
 *  This routine appends @a the_node onto the end of @a the_chain.
 *
 *  @note It does NOT disable interrupts to ensure the atomicity of the
 *  append operation.
 */
RTEMS_INLINE_ROUTINE void rtems_chain_append_unprotected(
  rtems_chain_control *the_chain,
  rtems_chain_node    *the_node
)
{
  _Chain_Append_unprotected( the_chain, the_node );
}

/** @brief Prepend a Node
 *
 *  This routine prepends the_node onto the front of the_chain.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *  @param[in] the_node is the node to be prepended.
 *
 *  @note It disables interrupts to ensure the atomicity of the
 *        prepend operation.
 */
RTEMS_INLINE_ROUTINE void rtems_chain_prepend(
  rtems_chain_control *the_chain,
  rtems_chain_node    *the_node
)
{
  _Chain_Prepend( the_chain, the_node );
}

/** @brief Prepend a Node (unprotected)
 *
 *  This routine prepends the_node onto the front of the_chain.
 *
 *  @param[in] the_chain is the chain to be operated upon.
 *  @param[in] the_node is the node to be prepended.
 *
 *  @note It does NOT disable interrupts to ensure the atomicity of the
 *        prepend operation.
 */
RTEMS_INLINE_ROUTINE void rtems_chain_prepend_unprotected(
  rtems_chain_control *the_chain,
  rtems_chain_node    *the_node
)
{
  _Chain_Prepend_unprotected( the_chain, the_node );
}

/**
 * @brief Checks if the @a chain is empty and appends the @a node.
 *
 * Interrupts are disabled to ensure the atomicity of the operation.
 *
 * @retval true The chain was empty before the append.
 * @retval false The chain contained at least one node before the append.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_append_with_empty_check(
  rtems_chain_control *chain,
  rtems_chain_node *node
)
{
  return _Chain_Append_with_empty_check( chain, node );
}

/**
 * @brief Checks if the @a chain is empty and prepends the @a node.
 *
 * Interrupts are disabled to ensure the atomicity of the operation.
 *
 * @retval true The chain was empty before the prepend.
 * @retval false The chain contained at least one node before the prepend.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_prepend_with_empty_check(
  rtems_chain_control *chain,
  rtems_chain_node *node
)
{
  return _Chain_Prepend_with_empty_check( chain, node );
}

/**
 * @brief Tries to get the first @a node and check if the @a chain is empty
 * afterwards.
 *
 * This function removes the first node from the @a chain and returns a pointer
 * to that node in @a node.  If the @a chain is empty, then @c NULL is returned.
 *
 * Interrupts are disabled to ensure the atomicity of the operation.
 *
 * @retval true The chain is empty after the node removal.
 * @retval false The chain contained at least one node after the node removal.
 */
RTEMS_INLINE_ROUTINE bool rtems_chain_get_with_empty_check(
  rtems_chain_control *chain,
  rtems_chain_node **node
)
{
  return _Chain_Get_with_empty_check( chain, node );
}

/** @} */

#endif
/* end of include file */