libs/rt-thread
libs
/
rt-thread
4
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

fix memory check in rt_realloc function 

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@763 bbd45198-f89e-11dd-88c7-29a3b14d5316
This commit is contained in:
bernard.xiong 2010-06-09 06:43:14 +00:00
parent 3e141fce65
commit 17e528db4f
1 changed files with 22 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
src/mem.c
View File

@ -10,6 +10,8 @@
* Change Logs: * Change Logs:
* Date Author Notes * Date Author Notes
* 2008-7-12 Bernard the first version * 2008-7-12 Bernard the first version
* 2010-06-09 Bernard fix the end stub of heap
* fix memory check in rt_realloc function
*/ */
/* /*
@ -168,7 +170,7 @@ void rt_system_heap_init(void* begin_addr, void* end_addr)
begin_addr = (void*)RT_ALIGN((rt_uint32_t)begin_addr, RT_ALIGN_SIZE); begin_addr = (void*)RT_ALIGN((rt_uint32_t)begin_addr, RT_ALIGN_SIZE);
/* calculate the aligned memory size */ /* calculate the aligned memory size */
mem_size_aligned = RT_ALIGN((rt_uint32_t)end_addr - (rt_uint32_t)begin_addr, RT_ALIGN_SIZE) - 2 * sizeof(struct heap_mem); mem_size_aligned = RT_ALIGN((rt_uint32_t)end_addr - (rt_uint32_t)begin_addr, RT_ALIGN_SIZE) - 2 * SIZEOF_STRUCT_MEM;
/* point to begin address of heap */ /* point to begin address of heap */
heap_ptr = begin_addr; heap_ptr = begin_addr;
@ -180,16 +182,16 @@ void rt_system_heap_init(void* begin_addr, void* end_addr)
/* initialize the start of the heap */ /* initialize the start of the heap */
mem = (struct heap_mem *)heap_ptr; mem = (struct heap_mem *)heap_ptr;
mem->magic= HEAP_MAGIC; mem->magic= HEAP_MAGIC;
mem->next = mem_size_aligned; mem->next = mem_size_aligned + SIZEOF_STRUCT_MEM;
mem->prev = 0; mem->prev = 0;
mem->used = 0; mem->used = 0;
/* initialize the end of the heap */ /* initialize the end of the heap */
heap_end = (struct heap_mem *)&heap_ptr[mem_size_aligned]; heap_end = (struct heap_mem *)&heap_ptr[mem->next];
heap_end->magic= HEAP_MAGIC; heap_end->magic= HEAP_MAGIC;
heap_end->used = 1; heap_end->used = 1;
heap_end->next = mem_size_aligned; heap_end->next = mem_size_aligned + SIZEOF_STRUCT_MEM;
heap_end->prev = mem_size_aligned; heap_end->prev = mem_size_aligned + SIZEOF_STRUCT_MEM;
rt_sem_init(&heap_sem, "heap", 1, RT_IPC_FLAG_FIFO); rt_sem_init(&heap_sem, "heap", 1, RT_IPC_FLAG_FIFO);
@ -274,7 +276,7 @@ void *rt_malloc(rt_size_t size)
mem->next = ptr2; mem->next = ptr2;
mem->used = 1; mem->used = 1;
if (mem2->next != mem_size_aligned) if (mem2->next != mem_size_aligned + SIZEOF_STRUCT_MEM)
{ {
((struct heap_mem *)&heap_ptr[mem2->next])->prev = ptr2; ((struct heap_mem *)&heap_ptr[mem2->next])->prev = ptr2;
} }
@ -368,9 +370,16 @@ void *rt_realloc(void *rmem, rt_size_t newsize)
ptr = (rt_uint8_t *)mem - heap_ptr; ptr = (rt_uint8_t *)mem - heap_ptr;
size = mem->next - ptr - SIZEOF_STRUCT_MEM; size = mem->next - ptr - SIZEOF_STRUCT_MEM;
if (size == newsize)
{
/* the size is the same as */
rt_sem_release(&heap_sem);
return rmem;
}
if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE < size) if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE < size)
{ {
/* split memory block */
#ifdef RT_MEM_STATS #ifdef RT_MEM_STATS
used_mem -= (size - newsize); used_mem -= (size - newsize);
#endif #endif
@ -382,7 +391,7 @@ void *rt_realloc(void *rmem, rt_size_t newsize)
mem2->next = mem->next; mem2->next = mem->next;
mem2->prev = ptr; mem2->prev = ptr;
mem->next = ptr2; mem->next = ptr2;
if (mem2->next != mem_size_aligned) if (mem2->next != mem_size_aligned + SIZEOF_STRUCT_MEM)
{ {
((struct heap_mem *)&heap_ptr[mem2->next])->prev = ptr2; ((struct heap_mem *)&heap_ptr[mem2->next])->prev = ptr2;
} }
@ -396,9 +405,11 @@ void *rt_realloc(void *rmem, rt_size_t newsize)
/* expand memory */ /* expand memory */
nmem = rt_malloc(newsize); nmem = rt_malloc(newsize);
if (nmem != RT_NULL) /* check memory */
{
rt_memcpy(nmem, rmem, size < newsize ? size : newsize); rt_memcpy(nmem, rmem, size < newsize ? size : newsize);
rt_free(rmem); rt_free(rmem);
}
return nmem; return nmem;
} }