Segment Collection

A Segment Collection manages a collection of segments virtually arranged in a continuous linear space. More...

Data Structures
struct	segcol_funcs
	Struct that holds the function pointers for an implementation of segcol_t. More...
Typedefs
typedef struct segcol	segcol_t
	Opaque type for segment collection ADT.
typedef struct segcol_iter	segcol_iter_t
	Opaque type for segment collection iterator.
Functions
int	segcol_free (segcol_t *segcol)
	Frees the resources of a segcol_t.
int	segcol_append (segcol_t segcol, segment_t seg)
	Appends a segment to the segcol_t.
int	segcol_insert (segcol_t segcol, off_t offset, segment_t seg)
	Inserts a segment into the segcol_t.
int	segcol_delete (segcol_t segcol, segcol_t *deleted, off_t offset, off_t length)
	Deletes a logical range from the segcol_t.
int	segcol_find (segcol_t segcol, segcol_iter_t *iter, off_t offset)
	Finds the segment that contains a given logical offset.
int	segcol_get_size (segcol_t segcol, off_t size)
	Gets the size of the data contained in a segcol_t.
Iterator functions

int	segcol_iter_new (segcol_t segcol, segcol_iter_t *iter)
	Gets a new (forward) iterator for a segcol_t.
int	segcol_iter_next (segcol_iter_t *iter)
	Moves the segcol_iter_t to the next element.
int	segcol_iter_is_valid (segcol_iter_t iter, int valid)
	Whether the iter points to a valid element.
int	segcol_iter_get_segment (segcol_iter_t iter, segment_t *seg)
	Gets the segment pointed to by a segcol_iter_t.
int	segcol_iter_get_mapping (segcol_iter_t iter, off_t mapping)
	Gets the mapping (logical offset) of the segment pointed to by a segcol_iter_t.
int	segcol_iter_free (segcol_iter_t *iter)
	Frees a segcol_iter_t.
Internal functions

int	segcol_create_impl (segcol_t *segcol, void impl, struct segcol_funcs *funcs)
	Creates a segcol_t using a specific implementation.
void *	segcol_get_impl (segcol_t *segcol)
	Gets the implementation of a segcol_t.
void *	segcol_iter_get_impl (segcol_iter_t *iter)
	Gets the implementation of a segcol_t.
Constructors

int	segcol_list_new (segcol_t **segcol)
	Creates a new segcol_t using a linked list implementation.

Detailed Description

A Segment Collection manages a collection of segments virtually arranged in a continuous linear space.

There may be many implementations of the Segment Collection ADT, each with its own performance characteristics. To create a Segment Collection one must use the constructor functions defined in each implementation (eg segcol_list_new()).

A note on error codes: all functions return EINVAL when an invalid range is specified (eg an offset is outside the limits of the virtual space of a Segment Collection).

Function Documentation

int segcol_append	(	segcol_t *	segcol,
		segment_t *	seg
	)

Appends a segment to the segcol_t.

After the invocation of this function the segcol_t is responsible for the memory handling of the specified segment. The segment should not be further manipulated by the user.

Parameters:

	segcol	the segcol_t to append to
	seg	the segment to append

Returns:: the operation error code

Definition at line 127 of file segcol.c.

References segment_get_size().

Referenced by bless_buffer_save(), segcol_add_copy(), segcol_store_in_file(), and segcol_store_in_memory().

Here is the call graph for this function:

Here is the caller graph for this function:

int segcol_create_impl	(	segcol_t **	segcol,
		void *	impl,
		struct segcol_funcs *	funcs
	)

Creates a segcol_t using a specific implementation.

Parameters:

`[out]`	segcol	the created segcol_t
	impl	the implementation private data
	funcs	function pointers to the implementations' functions

Returns:: the operation status code

Definition at line 60 of file segcol.c.

Referenced by segcol_list_new().

Here is the caller graph for this function:

int segcol_delete	(	segcol_t *	segcol,
		segcol_t **	deleted,
		off_t	offset,
		off_t	length
	)

Deletes a logical range from the segcol_t.

Parameters:

	segcol	the segcol_t to delete from
`[out]`	deleted	if it is not NULL, on return it will point to a new segcol_t containing the deleted segments
	offset	the logical offset to start deleting at
	length	the length of the range to delete

Returns:: the operation error code

Definition at line 189 of file segcol.c.

Referenced by segcol_add_copy(), segcol_store_in_file(), and segcol_store_in_memory().

Here is the caller graph for this function:

int segcol_find	(	segcol_t *	segcol,
		segcol_iter_t **	iter,
		off_t	offset
	)

Finds the segment that contains a given logical offset.

Parameters:

	segcol	the segcol_t to search in
`[out]`	iter	a segcol_iter_t pointing to the found segment
	offset	the offset to search for

Returns:: the operation error code

Definition at line 210 of file segcol.c.

Referenced by find_seg_entry(), and segcol_foreach().

Here is the caller graph for this function:

int segcol_free ( segcol_t * segcol )

Frees the resources of a segcol_t.

After the invocation of this function it is an error to use the freed segcol_t.

Parameters:

segcol

the segcol_t to free

Returns:: the operation error code

Definition at line 108 of file segcol.c.

Referenced by bless_buffer_free(), bless_buffer_new(), and bless_buffer_save().

Here is the caller graph for this function:

int segcol_get_size	(	segcol_t *	segcol,
		off_t *	size
	)

Gets the size of the data contained in a segcol_t.

Parameters:

	segcol	the segcol to get the size of
`[out]`	size	the size of the segcol in bytes

Returns:: the operation error code

Definition at line 311 of file segcol.c.

Referenced by bless_buffer_get_size(), bless_buffer_save(), segcol_add_copy(), segcol_foreach(), segcol_store_in_file(), and segcol_store_in_memory().

Here is the caller graph for this function:

int segcol_insert	(	segcol_t *	segcol,
		off_t	offset,
		segment_t *	seg
	)

Inserts a segment into the segcol_t.

After the invocation of this function the segcol_t is responsible for the memory handling of the specified segment. The segment should not be further manipulated by the caller.

Parameters: