1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
|
/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012,2013 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT 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/RT 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 <http://www.gnu.org/licenses/>.
*/
/**
* @file chmemcore.c
* @brief Core memory manager code.
*
* @addtogroup memcore
* @details Core Memory Manager related APIs and services.
* <h2>Operation mode</h2>
* The core memory manager is a simplified allocator that only
* allows to allocate memory blocks without the possibility to
* free them.<br>
* 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.<br>
* 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_USE_MEMCORE
* option must be enabled in @p chconf.h.
* @{
*/
#include "ch.h"
#if CH_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_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_MEMCORE_SIZE)/MEM_ALIGN_SIZE];
nextmem = (uint8_t *)&buffer[0];
endmem = (uint8_t *)&buffer[MEM_ALIGN_NEXT(CH_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 <code>MEM_ALIGN_SIZE</code>.
*
* @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
* <code>MEM_ALIGN_SIZE</code>.
*
* @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.
*
* @api
*/
size_t chCoreStatus(void) {
return (size_t)(endmem - nextmem);
}
#endif /* CH_USE_MEMCORE */
/** @} */
|
