NAME
Flexi Map
DESCRIPTION
Flexi map implements a binary tree that stores user provided cl_fmap_item_t
structures. Each item stored in a flexi map has a unique user defined key
(duplicates are not allowed). Flexi map provides the ability to
efficiently search for an item given a key. Flexi map allows user defined
keys of any size. Storage for keys and a comparisson function are provided
by users to allow flexi map to store items with arbitrary key values.
Flexi map does not allocate any memory, and can therefore not fail
any operations due to insufficient memory. Flexi map can thus be useful
in minimizing the error paths in code.
Flexi map is not thread safe, and users must provide serialization when
adding and removing items from the map.
The flexi map functions operate on a cl_fmap_t structure which should
be treated as opaque and should be manipulated only through the provided
functions.
SEE ALSO
Structures:
cl_fmap_t, cl_fmap_item_t
Callbacks:
cl_pfn_fmap_apply_t
Item Manipulation:
cl_fmap_key
Initialization:
cl_fmap_init
Iteration:
cl_fmap_end, cl_fmap_head, cl_fmap_tail, cl_fmap_next, cl_fmap_prev
Manipulation:
cl_fmap_insert, cl_fmap_get, cl_fmap_remove_item, cl_fmap_remove,
cl_fmap_remove_all, cl_fmap_merge, cl_fmap_delta
Search:
cl_fmap_apply_func
Attributes:
cl_fmap_count, cl_is_fmap_empty,
NAME
cl_fmap_apply_func
DESCRIPTION
The cl_fmap_apply_func function executes a specified function
for every item stored in a flexi map.
SYNOPSIS
CL_EXPORT void CL_API
cl_fmap_apply_func(
IN const cl_fmap_t* const p_map,
IN cl_pfn_fmap_apply_t pfn_func,
IN const void* const context );
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure.
pfn_func
[in] Function invoked for every item in the flexi map.
See the cl_pfn_fmap_apply_t function type declaration for details
about the callback function.
context
[in] Value to pass to the callback functions to provide context.
RETURN VALUE
This function does not return a value.
NOTES
The function provided must not perform any map operations, as these
would corrupt the flexi map.
SEE ALSO
Flexi Map, cl_pfn_fmap_apply_t
NAME
cl_fmap_count
DESCRIPTION
The cl_fmap_count function returns the number of items stored
in a flexi map.
SYNOPSIS
CL_INLINE size_t CL_API
cl_fmap_count(
IN const cl_fmap_t* const p_map )
{
CL_ASSERT( p_map );
CL_ASSERT( p_map->state == CL_INITIALIZED );
return( p_map->count );
}
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure whose item count to return.
RETURN VALUE
Returns the number of items stored in the map.
SEE ALSO
Flexi Map, cl_is_fmap_empty
NAME
cl_fmap_delta
DESCRIPTION
The cl_fmap_delta function computes the differences between two maps.
SYNOPSIS
CL_EXPORT void CL_API
cl_fmap_delta(
IN OUT cl_fmap_t* const p_map1,
IN OUT cl_fmap_t* const p_map2,
OUT cl_fmap_t* const p_new,
OUT cl_fmap_t* const p_old );
PARAMETERS
p_map1
[in/out] Pointer to the first of two cl_fmap_t structures whose
differences to compute.
p_map2
[in/out] Pointer to the second of two cl_fmap_t structures whose
differences to compute.
p_new
[out] Pointer to an empty cl_fmap_t structure that contains the items
unique to p_map2 upon return from the function.
p_old
[out] Pointer to an empty cl_fmap_t structure that contains the items
unique to p_map1 upon return from the function.
RETURN VALUES
This function does not return a value.
NOTES
Items are evaluated based on their keys. Items that exist in both
p_map1 and p_map2 remain in their respective maps. Items that
exist only p_map1 are moved to p_old. Likewise, items that exist only
in p_map2 are moved to p_new. This function can be usefull in evaluating
changes between two maps.
Both maps pointed to by p_new and p_old must be empty on input. This
requirement removes the possibility of failures.
SEE ALSO
Flexi Map, cl_fmap_merge
NAME
cl_fmap_end
DESCRIPTION
The cl_fmap_end function returns the end of a flexi map.
SYNOPSIS
CL_INLINE const cl_fmap_item_t* const CL_API
cl_fmap_end(
IN const cl_fmap_t* const p_map )
{
CL_ASSERT( p_map );
CL_ASSERT( p_map->state == CL_INITIALIZED );
/* Nil is the end of the map. */
return( &p_map->nil );
}
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure whose end to return.
RETURN VALUE
Pointer to the end of the map.
NOTES
cl_fmap_end is useful for determining the validity of map items returned
by cl_fmap_head, cl_fmap_tail, cl_fmap_next, or cl_fmap_prev. If the map
item pointer returned by any of these functions compares to the end, the
end of the map was encoutered.
When using cl_fmap_head or cl_fmap_tail, this condition indicates that
the map is empty.
SEE ALSO
Flexi Map, cl_fmap_head, cl_fmap_tail, cl_fmap_next, cl_fmap_prev
NAME
cl_fmap_get
DESCRIPTION
The cl_fmap_get function returns the map item associated with a key.
SYNOPSIS
CL_EXPORT cl_fmap_item_t* CL_API
cl_fmap_get(
IN const cl_fmap_t* const p_map,
IN const void* const p_key );
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure from which to retrieve the
item with the specified key.
p_key
[in] Pointer to a key value used to search for the desired map item.
RETURN VALUES
Pointer to the map item with the desired key value.
Pointer to the map end if there was no item with the desired key value
stored in the flexi map.
NOTES
cl_fmap_get does not remove the item from the flexi map.
SEE ALSO
Flexi Map, cl_fmap_remove
NAME
cl_fmap_head
DESCRIPTION
The cl_fmap_head function returns the map item with the lowest key
value stored in a flexi map.
SYNOPSIS
CL_INLINE cl_fmap_item_t* CL_API
cl_fmap_head(
IN const cl_fmap_t* const p_map )
{
CL_ASSERT( p_map );
CL_ASSERT( p_map->state == CL_INITIALIZED );
return( (cl_fmap_item_t*)p_map->nil.pool_item.list_item.p_next );
}
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure whose item with the lowest key
is returned.
RETURN VALUES
Pointer to the map item with the lowest key in the flexi map.
Pointer to the map end if the flexi map was empty.
NOTES
cl_fmap_head does not remove the item from the map.
SEE ALSO
Flexi Map, cl_fmap_tail, cl_fmap_next, cl_fmap_prev, cl_fmap_end,
cl_fmap_item_t
NAME
cl_fmap_init
DESCRIPTION
The cl_fmap_init function initialized a flexi map for use.
SYNOPSIS
CL_EXPORT void CL_API
cl_fmap_init(
IN cl_fmap_t* const p_map,
IN cl_pfn_fmap_cmp_t pfn_compare );
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure to initialize.
pfn_compare
[in] Pointer to the compare function used to compare keys.
See the cl_pfn_fmap_cmp_t function type declaration for details
about the callback function.
RETURN VALUES
This function does not return a value.
NOTES
Allows calling flexi map manipulation functions.
SEE ALSO
Flexi Map, cl_fmap_insert, cl_fmap_remove
NAME
cl_fmap_insert
DESCRIPTION
The cl_fmap_insert function inserts a map item into a flexi map.
SYNOPSIS
CL_EXPORT cl_fmap_item_t* CL_API
cl_fmap_insert(
IN cl_fmap_t* const p_map,
IN const void* const p_key,
IN cl_fmap_item_t* const p_item );
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure into which to add the item.
p_key
[in] Pointer to the key value to assign to the item. Storage for
the key must be persistant, as only the pointer is stored. Users
are responsible for maintaining the validity of key pointers while
they are in use.
p_item
[in] Pointer to a cl_fmap_item_t stucture to insert into the flexi map.
RETURN VALUE
Pointer to the item in the map with the specified key. If insertion
was successful, this is the pointer to the item. If an item with the
specified key already exists in the map, the pointer to that item is
returned.
NOTES
Insertion operations may cause the flexi map to rebalance.
SEE ALSO
Flexi Map, cl_fmap_remove, cl_fmap_item_t
NAME
cl_fmap_item_t
DESCRIPTION
The cl_fmap_item_t structure is used by maps to store objects.
The cl_fmap_item_t structure should be treated as opaque and should
be manipulated only through the provided functions.
SYNOPSIS
typedef struct _cl_fmap_item
{
/* Must be first to allow casting. */
cl_pool_item_t pool_item;
struct _cl_fmap_item *p_left;
struct _cl_fmap_item *p_right;
struct _cl_fmap_item *p_up;
cl_map_color_t color;
TO_LONG_PTR( const void* , p_key) ;
#ifdef _DEBUG_
struct _cl_fmap *p_map;
#endif
} cl_fmap_item_t;
FIELDS
pool_item
Used to store the item in a doubly linked list, allowing more
efficient map traversal.
p_left
Pointer to the map item that is a child to the left of the node.
p_right
Pointer to the map item that is a child to the right of the node.
p_up
Pointer to the map item that is the parent of the node.
p_nil
Pointer to the map's NIL item, used as a terminator for leaves.
The NIL sentinel is in the cl_fmap_t structure.
color
Indicates whether a node is red or black in the map.
p_key
Pointer to the value that uniquely represents a node in a map. This
pointer is set by calling cl_fmap_insert and can be retrieved by
calling cl_fmap_key.
NOTES
None of the fields of this structure should be manipulated by users, as
they are crititcal to the proper operation of the map in which they
are stored.
To allow storing items in either a quick list, a quick pool, or a flexi
map, the map implementation guarantees that the map item can be safely
cast to a pool item used for storing an object in a quick pool, or cast to
a list item used for storing an object in a quick list. This removes the
need to embed a flexi map item, a list item, and a pool item in objects
that need to be stored in a quick list, a quick pool, and a flexi map.
The flexi map item is defined to be identical in layout as a map item.
SEE ALSO
Flexi Map, cl_fmap_insert, cl_fmap_key, cl_pool_item_t, cl_list_item_t
NAME
cl_fmap_key
DESCRIPTION
The cl_fmap_key function retrieves the key value of a map item.
SYNOPSIS
#pragma warning (push)
#pragma warning (disable :4244)
CL_INLINE const void* CL_API
cl_fmap_key(
IN const cl_fmap_item_t* const p_item )
{
CL_ASSERT( p_item );
return( p_item->p_key );
}
#pragma warning (pop )
PARAMETERS
p_item
[in] Pointer to a map item whose key value to return.
RETURN VALUE
Returns the a pointer to the key value for the specified map item.
The key value should not be modified to insure proper flexi map operation.
NOTES
The key value is set in a call to cl_fmap_insert.
SEE ALSO
Flexi Map, cl_fmap_insert
NAME
cl_fmap_merge
DESCRIPTION
The cl_fmap_merge function moves all items from one map to another,
excluding duplicates.
SYNOPSIS
CL_EXPORT void CL_API
cl_fmap_merge(
OUT cl_fmap_t* const p_dest_map,
IN OUT cl_fmap_t* const p_src_map );
PARAMETERS
p_dest_map
[out] Pointer to a cl_fmap_t structure to which items should be added.
p_src_map
[in/out] Pointer to a cl_fmap_t structure whose items to add
to p_dest_map.
RETURN VALUES
This function does not return a value.
NOTES
Items are evaluated based on their keys only.
Upon return from cl_fmap_merge, the flexi map referenced by p_src_map
contains all duplicate items.
SEE ALSO
Flexi Map, cl_fmap_delta
NAME
cl_fmap_next
DESCRIPTION
The cl_fmap_next function returns the map item with the next higher
key value than a specified map item.
SYNOPSIS
CL_INLINE cl_fmap_item_t* CL_API
cl_fmap_next(
IN const cl_fmap_item_t* const p_item )
{
CL_ASSERT( p_item );
return( (cl_fmap_item_t*)p_item->pool_item.list_item.p_next );
}
PARAMETERS
p_item
[in] Pointer to a map item whose successor to return.
RETURN VALUES
Pointer to the map item with the next higher key value in a flexi map.
Pointer to the map end if the specified item was the last item in
the flexi map.
SEE ALSO
Flexi Map, cl_fmap_head, cl_fmap_tail, cl_fmap_prev, cl_fmap_end,
cl_fmap_item_t
NAME
cl_fmap_prev
DESCRIPTION
The cl_fmap_prev function returns the map item with the next lower
key value than a precified map item.
SYNOPSIS
CL_INLINE cl_fmap_item_t* CL_API
cl_fmap_prev(
IN const cl_fmap_item_t* const p_item )
{
CL_ASSERT( p_item );
return( (cl_fmap_item_t*)p_item->pool_item.list_item.p_prev );
}
PARAMETERS
p_item
[in] Pointer to a map item whose predecessor to return.
RETURN VALUES
Pointer to the map item with the next lower key value in a flexi map.
Pointer to the map end if the specifid item was the first item in
the flexi map.
SEE ALSO
Flexi Map, cl_fmap_head, cl_fmap_tail, cl_fmap_next, cl_fmap_end,
cl_fmap_item_t
NAME
cl_fmap_remove
DESCRIPTION
The cl_fmap_remove function removes the map item with the specified key
from a flexi map.
SYNOPSIS
CL_EXPORT cl_fmap_item_t* CL_API
cl_fmap_remove(
IN cl_fmap_t* const p_map,
IN const void* const p_key );
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure from which to remove the item
with the specified key.
p_key
[in] Pointer to the key value used to search for the map item
to remove.
RETURN VALUES
Pointer to the removed map item if it was found.
Pointer to the map end if no item with the specified key exists in the
flexi map.
SEE ALSO
Flexi Map, cl_fmap_remove_item, cl_fmap_remove_all, cl_fmap_insert
NAME
cl_fmap_remove_all
DESCRIPTION
The cl_fmap_remove_all function removes all items in a flexi map,
leaving it empty.
SYNOPSIS
CL_INLINE void CL_API
cl_fmap_remove_all(
IN cl_fmap_t* const p_map )
{
CL_ASSERT( p_map );
CL_ASSERT( p_map->state == CL_INITIALIZED );
p_map->root.p_left = &p_map->nil;
p_map->nil.pool_item.list_item.p_next = &p_map->nil.pool_item.list_item;
p_map->nil.pool_item.list_item.p_prev = &p_map->nil.pool_item.list_item;
p_map->count = 0;
}
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure to empty.
RETURN VALUES
This function does not return a value.
SEE ALSO
Flexi Map, cl_fmap_remove, cl_fmap_remove_item
NAME
cl_fmap_remove_item
DESCRIPTION
The cl_fmap_remove_item function removes the specified map item
from a flexi map.
SYNOPSIS
CL_EXPORT void CL_API
cl_fmap_remove_item(
IN cl_fmap_t* const p_map,
IN cl_fmap_item_t* const p_item );
PARAMETERS
p_item
[in] Pointer to a map item to remove from its flexi map.
RETURN VALUES
This function does not return a value.
In a debug build, cl_fmap_remove_item asserts that the item being removed
is in the specified map.
NOTES
Removes the map item pointed to by p_item from its flexi map.
SEE ALSO
Flexi Map, cl_fmap_remove, cl_fmap_remove_all, cl_fmap_insert
NAME
cl_fmap_t
DESCRIPTION
Flexi map structure.
The cl_fmap_t structure should be treated as opaque and should
be manipulated only through the provided functions.
SYNOPSIS
typedef struct _cl_fmap
{
cl_fmap_item_t root;
cl_fmap_item_t nil;
cl_state_t state;
size_t count;
cl_pfn_fmap_cmp_t pfn_compare;
} cl_fmap_t;
PARAMETERS
root
Map item that serves as root of the map. The root is set up to
always have itself as parent. The left pointer is set to point to
the item at the root.
nil
Map item that serves as terminator for all leaves, as well as providing
the list item used as quick list for storing map items in a list for
faster traversal.
state
State of the map, used to verify that operations are permitted.
count
Number of items in the map.
pfn_compare
Pointer to a compare function to invoke to compare the keys of
items in the map.
SEE ALSO
Flexi Map, cl_pfn_fmap_cmp_t
NAME
cl_fmap_tail
DESCRIPTION
The cl_fmap_tail function returns the map item with the highest key
value stored in a flexi map.
SYNOPSIS
CL_INLINE cl_fmap_item_t* CL_API
cl_fmap_tail(
IN const cl_fmap_t* const p_map )
{
CL_ASSERT( p_map );
CL_ASSERT( p_map->state == CL_INITIALIZED );
return( (cl_fmap_item_t*)p_map->nil.pool_item.list_item.p_prev );
}
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure whose item with the highest key
is returned.
RETURN VALUES
Pointer to the map item with the highest key in the flexi map.
Pointer to the map end if the flexi map was empty.
NOTES
cl_fmap_end does not remove the item from the map.
SEE ALSO
Flexi Map, cl_fmap_head, cl_fmap_next, cl_fmap_prev, cl_fmap_end,
cl_fmap_item_t
NAME
cl_is_fmap_empty
DESCRIPTION
The cl_is_fmap_empty function returns whether a flexi map is empty.
SYNOPSIS
CL_INLINE boolean_t CL_API
cl_is_fmap_empty(
IN const cl_fmap_t* const p_map )
{
CL_ASSERT( p_map );
CL_ASSERT( p_map->state == CL_INITIALIZED );
return( p_map->count == 0 );
}
PARAMETERS
p_map
[in] Pointer to a cl_fmap_t structure to test for emptiness.
RETURN VALUES
TRUE if the flexi map is empty.
FALSE otherwise.
SEE ALSO
Flexi Map, cl_fmap_count, cl_fmap_remove_all
NAME
cl_pfn_fmap_apply_t
DESCRIPTION
The cl_pfn_fmap_apply_t function type defines the prototype for functions
used to iterate items in a flexi map.
SYNOPSIS
typedef void
(CL_API *cl_pfn_fmap_apply_t)(
IN cl_fmap_item_t* const p_map_item,
IN void* context );
PARAMETERS
p_map_item
[in] Pointer to a cl_fmap_item_t structure.
context
[in] Value passed to the callback function.
RETURN VALUE
This function does not return a value.
NOTES
This function type is provided as function prototype reference for the
function provided by users as a parameter to the cl_fmap_apply_func
function.
SEE ALSO
Flexi Map, cl_fmap_apply_func
NAME
cl_pfn_fmap_cmp_t
DESCRIPTION
The cl_pfn_fmap_cmp_t function type defines the prototype for functions
used to compare item keys in a flexi map.
SYNOPSIS
typedef intn_t
(CL_API *cl_pfn_fmap_cmp_t)(
IN const void* const p_key1,
IN const void* const p_key2 );
PARAMETERS
p_key1
[in] Pointer to the first of two keys to compare.
p_key2
[in] Pointer to the second of two keys to compare.
RETURN VALUE
Returns 0 if the keys match.
Returns less than 0 if p_key1 is less than p_key2.
Returns greater than 0 if p_key1 is greater than p_key2.
NOTES
This function type is provided as function prototype reference for the
function provided by users as a parameter to the cl_fmap_init function.
SEE ALSO
Flexi Map, cl_fmap_init