mem.h File Reference

#include "lwip/opt.h"

Include dependency graph for mem.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Macros
#define	MEM_SIZE_F   U16_F
#define	LWIP_MEM_ALIGN_SIZE(size)   (((size) + MEM_ALIGNMENT - 1) & ~(MEM_ALIGNMENT-1))
#define	LWIP_MEM_ALIGN_BUFFER(size)   (((size) + MEM_ALIGNMENT - 1))
#define	LWIP_MEM_ALIGN(addr)   ((void *)(((mem_ptr_t)(addr) + MEM_ALIGNMENT - 1) & ~(mem_ptr_t)(MEM_ALIGNMENT-1)))

Typedefs
typedef u16_t	mem_size_t

Functions
void	mem_init (void)
void *	mem_trim (void *mem, mem_size_t size)
void *	mem_malloc (mem_size_t size)
void *	mem_calloc (mem_size_t count, mem_size_t size)
void	mem_free (void *mem)

Macro Definition Documentation

LWIP_MEM_ALIGN

#define LWIP_MEM_ALIGN

(

addr

)

((void *)(((mem_ptr_t)(addr) + MEM_ALIGNMENT - 1) & ~(mem_ptr_t)(MEM_ALIGNMENT-1)))

Align a memory pointer to the alignment defined by MEM_ALIGNMENT so that ADDR % MEM_ALIGNMENT == 0

Definition at line 116 of file mem.h.

LWIP_MEM_ALIGN_BUFFER

#define LWIP_MEM_ALIGN_BUFFER

(

size

)

(((size) + MEM_ALIGNMENT - 1))

Calculate safe memory size for an aligned buffer when using an unaligned type as storage. This includes a safety-margin on (MEM_ALIGNMENT - 1) at the start (e.g. if buffer is u8_t[] and actual data will be u32_t*)

Definition at line 109 of file mem.h.

LWIP_MEM_ALIGN_SIZE

#define LWIP_MEM_ALIGN_SIZE

(

size

)

(((size) + MEM_ALIGNMENT - 1) & ~(MEM_ALIGNMENT-1))

Calculate memory size for an aligned buffer - returns the next highest multiple of MEM_ALIGNMENT (e.g. LWIP_MEM_ALIGN_SIZE(3) and LWIP_MEM_ALIGN_SIZE(4) will both yield 4 for MEM_ALIGNMENT == 4).

Definition at line 101 of file mem.h.

MEM_SIZE_F

#define MEM_SIZE_F   U16_F

Definition at line 77 of file mem.h.

Typedef Documentation

mem_size_t

typedef u16_t mem_size_t

Definition at line 76 of file mem.h.

Function Documentation

mem_calloc()

void * mem_calloc	(	mem_size_t	count,
		mem_size_t	size
	)

Contiguously allocates enough space for count objects that are size bytes of memory each and returns a pointer to the allocated memory.

The allocated memory is filled with bytes of value zero.

Parameters

count	number of objects to allocate
size	size of the objects to allocate

Returns

pointer to allocated memory / NULL pointer if there is an error

Definition at line 646 of file mem.c.

mem_free()

void mem_free

(

void *

rmem

)

Put a struct mem back on the heap

Parameters

rmem	is the data portion of a struct mem as returned by a previous call to mem_malloc()

Definition at line 311 of file mem.c.

mem_init()

void mem_init

(

void

)

Zero the heap and initialize start, end and lowest-free

Definition at line 274 of file mem.c.

mem_malloc()

void * mem_malloc

(

mem_size_t

size

)

Adam's mem_malloc() plus solution for bug #17922 Allocate a block of memory with a minimum of 'size' bytes.

Parameters

size	is the minimum size of the requested block in bytes.

Returns

pointer to allocated memory or NULL if no free memory was found.

Note that the returned value will always be aligned (as defined by MEM_ALIGNMENT).

Definition at line 494 of file mem.c.

mem_trim()

void * mem_trim	(	void *	rmem,
		mem_size_t	newsize
	)

Shrink memory returned by mem_malloc().

Parameters

rmem	pointer to memory allocated by mem_malloc the is to be shrinked
newsize	required size after shrinking (needs to be smaller than or equal to the previous size)

Returns

for compatibility reasons: is always == rmem, at the moment or NULL if newsize is > old size, in which case rmem is NOT touched or freed!

Definition at line 369 of file mem.c.