mem.i

凌阳单片机之以太网通讯模组模组

# 1 "E:/GJ155/code/core/mem.c"
 





 






































# 75 "E:/GJ155/code/core/mem.c"







static struct mem *ram_end;

 
u8_t ram[MEM_SIZE + sizeof(struct mem) + MEM_ALIGNMENT];






static struct mem *lfree;    


static sys_sem_t mem_sem;


static void
plug_holes(struct mem *mem)
{
  struct mem *nmem;
  struct mem *pmem;

  LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
  LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t *)mem < (u8_t *)ram_end);
  LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
  
   
  LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE", mem->next <= MEM_SIZE);
  
  nmem = (struct mem *)&ram[mem->next];
  if (mem != nmem && nmem->used == 0 && (u8_t *)nmem != (u8_t *)ram_end) {
    if (lfree == nmem) {
      lfree = mem;
    }
    mem->next = nmem->next;
    ((struct mem *)&ram[nmem->next])->prev = (u8_t *)mem - ram;
  }

   
  pmem = (struct mem *)&ram[mem->prev];
  if (pmem != mem && pmem->used == 0) {
    if (lfree == mem) {
      lfree = pmem;
    }
    pmem->next = mem->next;
    ((struct mem *)&ram[mem->next])->prev = (u8_t *)pmem - ram;
  }
}

void
mem_init(void)
{
  struct mem *mem;

  memset(ram, 0, MEM_SIZE);
  mem = (struct mem *)ram;
  mem->next = MEM_SIZE;
  mem->prev = 0;
  mem->used = 0;
  ram_end = (struct mem *)&ram[MEM_SIZE];
  ram_end->used = 1;
  ram_end->next = MEM_SIZE;
  ram_end->prev = MEM_SIZE;

  mem_sem = sys_sem_new(1);

  lfree = (struct mem *)ram;




}
void
mem_free(void *rmem)
{
  struct mem *mem;
   
  if (rmem == NULL) {
    DEBUGF(MEM_DEBUG | DBG_TRACE | 2, ("mem_free(p == NULL) was called.\n"));
    return;
  }
  
  sys_sem_wait(mem_sem);
  

  LWIP_ASSERT("mem_free: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
    (u8_t *)rmem < (u8_t *)ram_end);
  
  if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
    DEBUGF(MEM_DEBUG | 3, ("mem_free: illegal memory\n"));




    sys_sem_signal(mem_sem);
    
    return;
  }
  mem = (struct mem *)((u8_t *)rmem - MEM_ALIGN_SIZE(sizeof(struct mem)) );

  LWIP_ASSERT("mem_free: mem->used", mem->used); 
  mem->used = 0;

  if (mem < lfree) {
    lfree = mem;
  }
  



  plug_holes(mem);
  sys_sem_signal(mem_sem);
}
void *
mem_reallocm(void *rmem, mem_size_t newsize)
{
  void *nmem;
  nmem = mem_malloc(newsize);
  if (nmem == NULL) {
    return mem_realloc(rmem, newsize);
  }
  memcpy(nmem, rmem, newsize);
  mem_free(rmem);
  return nmem;
}
 
void *
mem_realloc(void *rmem, mem_size_t newsize)
{
  mem_size_t size;
  mem_size_t ptr, ptr2;
  struct mem *mem, *mem2;

   

  if ((newsize % MEM_ALIGNMENT) != 0) {
   newsize += MEM_ALIGNMENT - ((newsize + MEM_ALIGN_SIZE(sizeof(struct mem)) ) % MEM_ALIGNMENT);
  }
  
  if (newsize > MEM_SIZE) {
    return NULL;
  }
  
  sys_sem_wait(mem_sem);
  
  LWIP_ASSERT("mem_realloc: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
	 (u8_t *)rmem < (u8_t *)ram_end);
  
  if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
    DEBUGF(MEM_DEBUG | 3, ("mem_realloc: illegal memory\n"));
    return rmem;
  }
  mem = (struct mem *)((u8_t *)rmem - MEM_ALIGN_SIZE(sizeof(struct mem)) );

  ptr = (u8_t *)mem - ram;

  size = mem->next - ptr - MEM_ALIGN_SIZE(sizeof(struct mem)) ;



  
  if (newsize + MEM_ALIGN_SIZE(sizeof(struct mem))  + 12  < size) {
    ptr2 = ptr + MEM_ALIGN_SIZE(sizeof(struct mem))  + newsize;
    mem2 = (struct mem *)&ram[ptr2];
    mem2->used = 0;
    mem2->next = mem->next;
    mem2->prev = ptr;
    mem->next = ptr2;
    if (mem2->next != MEM_SIZE) {
      ((struct mem *)&ram[mem2->next])->prev = ptr2;
    }

    plug_holes(mem2);
  }
  sys_sem_signal(mem_sem);  
  return rmem;
}
void *
mem_malloc(mem_size_t size)
{
  mem_size_t ptr, ptr2;
  struct mem *mem, *mem2;

  if (size == 0) {
    return NULL;
  }

   

  if ((size % MEM_ALIGNMENT) != 0) {
    size += MEM_ALIGNMENT - ((size + MEM_ALIGN_SIZE(sizeof(struct mem)) ) % MEM_ALIGNMENT);
  }
  
  if (size > MEM_SIZE) {
    return NULL;
  }
  
  sys_sem_wait(mem_sem);

  for (ptr = (u8_t *)lfree - ram; ptr < MEM_SIZE; ptr = ((struct mem *)&ram[ptr])->next) {
    mem = (struct mem *)&ram[ptr];
    if (!mem->used &&
       mem->next - (ptr + MEM_ALIGN_SIZE(sizeof(struct mem)) ) >= size + MEM_ALIGN_SIZE(sizeof(struct mem)) ) {
      ptr2 = ptr + MEM_ALIGN_SIZE(sizeof(struct mem))  + size;
      mem2 = (struct mem *)&ram[ptr2];
        
      mem2->prev = ptr;      
      mem2->next = mem->next;
      mem->next = ptr2;      

      if (mem2->next != MEM_SIZE) {
        ((struct mem *)&ram[mem2->next])->prev = ptr2;
      }
      
      mem2->used = 0;      
      mem->used = 1;
# 306 "E:/GJ155/code/core/mem.c"


      if (mem == lfree) {
	 
        while (lfree->used && lfree != ram_end) {
	  lfree = (struct mem *)&ram[lfree->next];
        }
        LWIP_ASSERT("mem_malloc: !lfree->used", !lfree->used);
      }
      sys_sem_signal(mem_sem);
      LWIP_ASSERT("mem_malloc: allocated memory not above ram_end.",
	     (u16_t)mem + MEM_ALIGN_SIZE(sizeof(struct mem))  + size <= (u16_t)ram_end);
      LWIP_ASSERT("mem_malloc: allocated memory properly aligned.",
	     (u16_t)((u8_t *)mem + MEM_ALIGN_SIZE(sizeof(struct mem)) ) % MEM_ALIGNMENT == 0);
      return (u8_t *)mem + MEM_ALIGN_SIZE(sizeof(struct mem)) ;
    }    
  }
  DEBUGF(MEM_DEBUG | 2, ("mem_malloc: could not allocate %d bytes\n", (int)size));


  
  sys_sem_signal(mem_sem);
  return NULL;
}