/*
ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio.
This file is part of ChibiOS.
ChibiOS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
/**
* @file chmemcore.c
* @brief Core memory manager code.
*
* @addtogroup memcore
* @details Core Memory Manager related APIs and services.
*
Operation mode
* The core memory manager is a simplified allocator that only
* allows to allocate memory blocks without the possibility to
* free them.
* This allocator is meant as a memory blocks provider for the
* other allocators such as:
* - C-Runtime allocator (through a compiler specific adapter module).
* - Heap allocator (see @ref heaps).
* - Memory pools allocator (see @ref pools).
* .
* By having a centralized memory provider the various allocators
* can coexist and share the main memory.
* This allocator, alone, is also useful for very simple
* applications that just require a simple way to get memory
* blocks.
* @pre In order to use the core memory manager APIs the @p CH_CFG_USE_MEMCORE
* option must be enabled in @p chconf.h.
* @{
*/
#include "ch.h"
#if CH_CFG_USE_MEMCORE || defined(__DOXYGEN__)
/*===========================================================================*/
/* Module exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local types. */
/*===========================================================================*/
/*===========================================================================*/
/* Module local variables. */
/*===========================================================================*/
static uint8_t *nextmem;
static uint8_t *endmem;
/*===========================================================================*/
/* Module local functions. */
/*===========================================================================*/
/*===========================================================================*/
/* Module exported functions. */
/*===========================================================================*/
/**
* @brief Low level memory manager initialization.
*
* @notapi
*/
void _core_init(void) {
#if CH_CFG_MEMCORE_SIZE == 0
extern uint8_t __heap_base__[];
extern uint8_t __heap_end__[];
nextmem = (uint8_t *)MEM_ALIGN_NEXT(__heap_base__);
endmem = (uint8_t *)MEM_ALIGN_PREV(__heap_end__);
#else
static stkalign_t buffer[MEM_ALIGN_NEXT(CH_CFG_MEMCORE_SIZE)/MEM_ALIGN_SIZE];
nextmem = (uint8_t *)&buffer[0];
endmem = (uint8_t *)&buffer[MEM_ALIGN_NEXT(CH_CFG_MEMCORE_SIZE)/MEM_ALIGN_SIZE];
#endif
}
/**
* @brief Allocates a memory block.
* @details The size of the returned block is aligned to the alignment
* type so it is not possible to allocate less
* than MEM_ALIGN_SIZE
.
*
* @param[in] size the size of the block to be allocated
* @return A pointer to the allocated memory block.
* @retval NULL allocation failed, core memory exhausted.
*
* @api
*/
void *chCoreAlloc(size_t size) {
void *p;
chSysLock();
p = chCoreAllocI(size);
chSysUnlock();
return p;
}
/**
* @brief Allocates a memory block.
* @details The size of the returned block is aligned to the alignment
* type so it is not possible to allocate less than
* MEM_ALIGN_SIZE
.
*
* @param[in] size the size of the block to be allocated.
* @return A pointer to the allocated memory block.
* @retval NULL allocation failed, core memory exhausted.
*
* @iclass
*/
void *chCoreAllocI(size_t size) {
void *p;
chDbgCheckClassI();
size = MEM_ALIGN_NEXT(size);
if ((size_t)(endmem - nextmem) < size)
return NULL;
p = nextmem;
nextmem += size;
return p;
}
/**
* @brief Core memory status.
*
* @return The size, in bytes, of the free core memory.
*
* @xclass
*/
size_t chCoreGetStatusX(void) {
return (size_t)(endmem - nextmem);
}
#endif /* CH_CFG_USE_MEMCORE */
/** @} */