ext.h File Reference

'compositing' using talloc structures More...

#include <freeradius-devel/util/table.h>
#include <limits.h>

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Data Structures
struct	fr_ext_hdr_t
	Optional extension header struct. More...
struct	fr_ext_info_t
	Additional information for a given extension. More...
struct	fr_ext_s
	Structure to define a set of extensions. More...

Macros
#define	FR_EXT_ALIGNMENT   sizeof(uint64_t)
	The alignment of object extension structures. More...

Typedefs
typedef void *(*	fr_ext_alloc_t) (fr_ext_t const *def, TALLOC_CTX **dst_chunk_p, int ext, void *src_ext_ptr, size_t src_ext_len)
	Function for pre-allocating extension memory for extensions before they're copied. More...
typedef int(*	fr_ext_copy_t) (int ext, TALLOC_CTX *dst_chunk, void *dst_ext_ptr, size_t dst_ext_len, TALLOC_CTX const *src_chunk, void *src_ext_ptr, size_t src_ext_len)
	Function for re-populating extensions after they're copied. More...
typedef int(*	fr_ext_fixup_t) (int ext, TALLOC_CTX *chunk, void *ext_ptr, size_t ext_len)
	Function for re-establishing internal consistency on realloc. More...
typedef struct fr_ext_s	fr_ext_t

Functions
void *	fr_ext_alloc_size (fr_ext_t const *def, TALLOC_CTX **chunk_p, int ext, size_t ext_len)
void *	fr_ext_copy (fr_ext_t const *def, TALLOC_CTX **chunk_out, TALLOC_CTX const *chunk_in, int ext)
	Copy extension data from one attribute to another. More...
int	fr_ext_copy_all (fr_ext_t const *def, TALLOC_CTX **chunk_out, TALLOC_CTX const *chunk_in)
	Copy all the extensions from one attribute to another. More...
void	fr_ext_debug (fr_ext_t const *def, char const *name, TALLOC_CTX const *chunk)
size_t	fr_ext_len (fr_ext_t const *def, TALLOC_CTX const *chunk_in, int ext)
	Return the length of an extension. More...
static uint8_t *	fr_ext_offsets (fr_ext_t const *def, TALLOC_CTX const *chunk)
static void *	fr_ext_ptr (TALLOC_CTX const *chunk, size_t offset, bool has_hdr)
	Return a pointer to an extension in a chunk. More...

Detailed Description

'compositing' using talloc structures

These allow multiple variable length memory areas to be appended to talloced structures. Extensions can either contain a header in which case the exact length is recorded, or they can be of a fixed size.

The structure being extended must be padded to a multiple of FR_EXT_ALIGNMENT. i.e. ).

It is strongly recommended that extended structures are allocated in a talloc_pool() to avoid the overhead of multiple reallocs.

Copyright

2020 The FreeRADIUS server project

2020 Arran Cudbard-Bell a.cud.nosp@m.bard.nosp@m.b@fre.nosp@m.erad.nosp@m.ius.o.nosp@m.rg

Definition in file ext.h.

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Data Structure Documentation

fr_ext_hdr_t

struct fr_ext_hdr_t

Optional extension header struct.

Definition at line 137 of file ext.h.

Data Fields
uint8_t	data[]	Extension data.
size_t	len	Length of extension data.

fr_ext_info_t

struct fr_ext_info_t

Additional information for a given extension.

Definition at line 111 of file ext.h.

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Data Fields
fr_ext_alloc_t	alloc	Override the normal alloc operation with a callback.
bool	can_copy	Copying this extension between structs is allowed.
fr_ext_copy_t	copy	Override the normal copy operation with a callback.
fr_ext_fixup_t	fixup	Callback for fixing up internal consistency issues.
bool	has_hdr	Additional metadata should be allocated before the extension data to record the exact length of the extension.
size_t	min	Minimum size of extension.

fr_ext_s

struct fr_ext_s

Structure to define a set of extensions.

Definition at line 126 of file ext.h.

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Data Fields
fr_ext_info_t const *	info	Additional information about each extension.
int	max	The highest extension value.
fr_table_num_ordered_t const *	name_table	String identifiers for the extensions.
size_t *	name_table_len	How many extensions there are in the table.
size_t	offset_of_exts	Where in the extended struct the extensions array starts.

Macro Definition Documentation

FR_EXT_ALIGNMENT

#define FR_EXT_ALIGNMENT   sizeof(uint64_t)

The alignment of object extension structures.

Definition at line 54 of file ext.h.

Typedef Documentation

fr_ext_alloc_t

typedef void*(* fr_ext_alloc_t) (fr_ext_t const *def, TALLOC_CTX **dst_chunk_p, int ext, void *src_ext_ptr, size_t src_ext_len)

Function for pre-allocating extension memory for extensions before they're copied.

Parameters

[in]	def	Extension definitions.
[in,out]	dst_chunk_p	to add extensions to.
[in]	ext	that's being copied.
[in]	src_ext_ptr	Pointer for the src extension.
[in]	src_ext_len	Length of the src extension.

Returns

• NULL on error.
• Pointer to the new extension on success.

Definition at line 70 of file ext.h.

fr_ext_copy_t

typedef int(* fr_ext_copy_t) (int ext, TALLOC_CTX *dst_chunk, void *dst_ext_ptr, size_t dst_ext_len, TALLOC_CTX const *src_chunk, void *src_ext_ptr, size_t src_ext_len)

Function for re-populating extensions after they're copied.

Parameters

[in]	ext	that's being copied.
[in]	dst_chunk	Talloc chunk we're copying to.
[in]	dst_ext_ptr	Pointer to the dst extension to populate.
[in]	dst_ext_len	The length of the dst extension.
[in]	src_chunk	Talloc chunk we're copying from.
[in]	src_ext_ptr	Pointer for the src extension.
[in]	src_ext_len	Length of the src extension.

Returns

• NULL on error.
• Pointer to the new extension on success.

Definition at line 86 of file ext.h.

fr_ext_fixup_t

typedef int(* fr_ext_fixup_t) (int ext, TALLOC_CTX *chunk, void *ext_ptr, size_t ext_len)

Function for re-establishing internal consistency on realloc.

In some cases the chunk may cache a pointer to an extension. On realloc this pointer may be invalidated. This provides a callback to fixup consistency issues after a realloc.

Parameters

[in]	ext	that's being copied.
[in]	chunk	Talloc chunk.
[in]	ext_ptr	Pointer to the extension to fixup.
[in]	ext_len	The length of the extension to fixup.

Returns

• NULL on error.
• Pointer to the new extension on success.

Definition at line 106 of file ext.h.

fr_ext_t

typedef struct fr_ext_s fr_ext_t

Definition at line 1 of file ext.h.

Function Documentation

fr_ext_alloc_size()

void* fr_ext_alloc_size	(	fr_ext_t const *	def,
		TALLOC_CTX **	chunk_p,
		int	ext,
		size_t	ext_len
	)

fr_ext_copy()

void* fr_ext_copy	(	fr_ext_t const *	def,
		TALLOC_CTX **	chunk_dst,
		TALLOC_CTX const *	chunk_src,
		int	ext
	)

Copy extension data from one attribute to another.

Parameters

[in]	def	Extension definitions.
[in,out]	chunk_dst	to copy extension to. Under certain circumstances the value of *chunk_dst will be changed to point to a new memory block. All cached copies of the previous pointer should be updated.
[in]	chunk_src	to copy extension from.
[in]	ext	to copy.

Returns

• NULL if we failed to allocate an extension structure.
• A pointer to the offset of the extension in da_out.

Definition at line 160 of file ext.c.

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fr_ext_copy_all()

int fr_ext_copy_all	(	fr_ext_t const *	def,
		TALLOC_CTX **	chunk_dst,
		TALLOC_CTX const *	chunk_src
	)

Copy all the extensions from one attribute to another.

Parameters

[in]	def	Extension definitions.
[in,out]	chunk_dst	to copy extensions to. Under certain circumstances the value of *chunk_dst will be changed to point to a new memory block. All cached copies of the previous pointer should be updated.
[in]	chunk_src	to copy extensions from.

Returns

• 0 on success.
• -1 if a copy operation failed.

Definition at line 245 of file ext.c.

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fr_ext_debug()

void fr_ext_debug	(	fr_ext_t const *	def,
		char const *	name,
		TALLOC_CTX const *	chunk
	)

fr_ext_len()

size_t fr_ext_len	(	fr_ext_t const *	def,
		TALLOC_CTX const *	chunk,
		int	ext
	)

Return the length of an extension.

Parameters

[in]	def	Extension definitions.
[in]	chunk	to return extension length for.
[in]	ext	to return length for.

Returns

• 0 if no extension exists or is of zero length.
• >0 the length of the extension.

Definition at line 128 of file ext.c.

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fr_ext_offsets()

static uint8_t* fr_ext_offsets ( fr_ext_t const *  def, TALLOC_CTX const *  chunk  )

inlinestatic

Definition at line 142 of file ext.h.

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fr_ext_ptr()

static void* fr_ext_ptr ( TALLOC_CTX const *  chunk, size_t  offset, bool  has_hdr  )

inlinestatic

Return a pointer to an extension in a chunk.

Definition at line 150 of file ext.h.

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