Files
libcoap/include/coap/mem.h
T
Olaf Bergmann ecda1426ac resource.c: Increase use of coap_malloc_type() and coap_free_type()
coap_malloc_type() and coap_free_type() provide an abstract API for
dynamic memory management on different platforms. resource.c still
is in transition and needs more cleanup.
2015-03-11 14:59:40 +01:00

97 lines
3.0 KiB
C

/* mem.h -- CoAP memory handling
*
* Copyright (C) 2010,2011,2014,2015 Olaf Bergmann <bergmann@tzi.org>
*
* This file is part of the CoAP library libcoap. Please see
* README for terms of use.
*/
#ifndef _COAP_MEM_H_
#define _COAP_MEM_H_
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifndef WITH_LWIP
/**
* Initializes libcoap's memory management. This function must be
* called once before coap_malloc() can be used on constrained
* devices.
*/
void coap_memory_init(void);
#endif /* WITH_LWIP */
/**
* Type specifiers for coap_malloc_type(). Memory objects can be typed
* to facilitate arrays of type objects to be used instead of dynamic
* memory management on constrained devices.
*/
typedef enum {
COAP_STRING, COAP_ATTRIBUTE_NAME, COAP_ATTRIBUTE_VALUE, COAP_PACKET, COAP_NODE, COAP_CONTEXT, COAP_ENDPOINT, COAP_PDU, COAP_PDU_BUF, COAP_RESOURCE, COAP_RESOURCEATTR
} coap_memory_tag_t;
#ifndef WITH_LWIP
/**
* Allocates a chunk of @p size bytes and returns a pointer to the
* newly allocated memory. The @p type is used to select the
* appropriate storage container on constrained devices. The storage
* allocated by coap_malloc_type() must be released with
* coap_free_type().
*
* @param type The type of object to be stored.
* @param size The number of bytes requested.
* @return A pointer to the allocated storage or @c NULL on error.
*/
void *coap_malloc_type(coap_memory_tag_t type, size_t size);
/**
* Releases the memory that was allocated by coap_malloc_type(). The
* type tag @p type must be the same that was used for allocating the
* object pointed to by @p.
*
* @param type The type of the object to release.
* @param p A pointer to memory that was allocated by
* coap_malloc_type().
*/
void coap_free_type(coap_memory_tag_t type, void *p);
/**
* Wrapper function to coap_malloc_type() for backwards compatibility.
*/
static inline void *coap_malloc(size_t size) {
return coap_malloc_type(COAP_STRING, size);
}
/**
* Wrapper function to coap_free_type() for backwards compatibility.
*/
static inline void coap_free(void *object) {
coap_free_type(COAP_STRING, object);
}
#endif /* not WITH_LWIP */
#ifdef WITH_LWIP
#include <lwip/memp.h>
/* no initialization needed with lwip (or, more precisely: lwip must be
* completely initialized anyway by the time coap gets active) */
static inline void coap_memory_init(void) {}
/* it would be nice to check that size equals the size given at the memp
* declaration, but i currently don't see a standard way to check that without
* sourcing the custom memp pools and becoming dependent of its syntax */
#define coap_malloc_type(type, size) memp_malloc(MEMP_ ## type)
#define coap_free_type(type, p) memp_free(MEMP_ ## type, p)
/* those are just here to make uri.c happy where string allocation has not been made conditional */
static inline void *coap_malloc(size_t size) { LWIP_ASSERT("coap_malloc must not be used in lwIP", 0); }
static inline void coap_free(void *pointer) { LWIP_ASSERT("coap_free must not be used in lwIP", 0); }
#endif /* WITH_LWIP */
#endif /* _COAP_MEM_H_ */