gmem.c

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	  if (mem_chunk->mem_areas)
	    mem_chunk->mem_areas->prev = mem_chunk->mem_area;
	  mem_chunk->mem_areas = mem_chunk->mem_area;
	  
	  if (mem_chunk->type == G_ALLOC_AND_FREE)
	    g_tree_insert (mem_chunk->mem_tree, mem_chunk->mem_area, mem_chunk->mem_area);
        }
      
      mem_chunk->mem_area->index = 0;
      mem_chunk->mem_area->free = mem_chunk->area_size;
      mem_chunk->mem_area->allocated = 0;
      mem_chunk->mem_area->mark = 0;
    }
  
  /* Get the memory and modify the state variables appropriately.
   */
  mem = (gpointer) &mem_chunk->mem_area->mem[mem_chunk->mem_area->index];
  mem_chunk->mem_area->index += mem_chunk->atom_size;
  mem_chunk->mem_area->free -= mem_chunk->atom_size;
  mem_chunk->mem_area->allocated += 1;

outa_here:

  LEAVE_MEM_CHUNK_ROUTINE ();

  return mem;
}

gpointer
g_mem_chunk_alloc0 (GMemChunk *mem_chunk)
{
  gpointer mem;

  mem = g_mem_chunk_alloc (mem_chunk);
  if (mem)
    {
      memset (mem, 0, mem_chunk->atom_size);
    }

  return mem;
}

void
g_mem_chunk_free (GMemChunk *mem_chunk,
		  gpointer   mem)
{
  GMemArea *temp_area;
  GFreeAtom *free_atom;
  
  g_return_if_fail (mem_chunk != NULL);
  g_return_if_fail (mem != NULL);

  ENTER_MEM_CHUNK_ROUTINE ();

#ifdef ENABLE_GC_FRIENDLY
  memset (mem, 0, mem_chunk->atom_size);
#endif /* ENABLE_GC_FRIENDLY */

  /* Don't do anything if this is an ALLOC_ONLY chunk
   */
  if (mem_chunk->type == G_ALLOC_AND_FREE)
    {
      /* Place the memory on the "free_atoms" list
       */
      free_atom = (GFreeAtom*) mem;
      free_atom->next = mem_chunk->free_atoms;
      mem_chunk->free_atoms = free_atom;
      
      temp_area = g_tree_search (mem_chunk->mem_tree,
				 (GCompareFunc) g_mem_chunk_area_search,
				 mem);
      
      temp_area->allocated -= 1;
      
      if (temp_area->allocated == 0)
	{
	  temp_area->mark = 1;
	  mem_chunk->num_marked_areas += 1;
	}
    }

  LEAVE_MEM_CHUNK_ROUTINE ();
}

/* This doesn't free the free_area if there is one */
void
g_mem_chunk_clean (GMemChunk *mem_chunk)
{
  GMemArea *mem_area;
  GFreeAtom *prev_free_atom;
  GFreeAtom *temp_free_atom;
  gpointer mem;
  
  g_return_if_fail (mem_chunk != NULL);
  
  ENTER_MEM_CHUNK_ROUTINE ();

  if (mem_chunk->type == G_ALLOC_AND_FREE)
    {
      prev_free_atom = NULL;
      temp_free_atom = mem_chunk->free_atoms;
      
      while (temp_free_atom)
	{
	  mem = (gpointer) temp_free_atom;
	  
	  mem_area = g_tree_search (mem_chunk->mem_tree,
				    (GCompareFunc) g_mem_chunk_area_search,
				    mem);
	  
          /* If this mem area is marked for destruction then delete the
	   *  area and list node and decrement the free mem.
           */
	  if (mem_area->mark)
	    {
	      if (prev_free_atom)
		prev_free_atom->next = temp_free_atom->next;
	      else
		mem_chunk->free_atoms = temp_free_atom->next;
	      temp_free_atom = temp_free_atom->next;
	      
	      mem_area->free += mem_chunk->atom_size;
	      if (mem_area->free == mem_chunk->area_size)
		{
		  mem_chunk->num_mem_areas -= 1;
		  mem_chunk->num_marked_areas -= 1;
		  
		  if (mem_area->next)
		    mem_area->next->prev = mem_area->prev;
		  if (mem_area->prev)
		    mem_area->prev->next = mem_area->next;
		  if (mem_area == mem_chunk->mem_areas)
		    mem_chunk->mem_areas = mem_chunk->mem_areas->next;
		  if (mem_area == mem_chunk->mem_area)
		    mem_chunk->mem_area = NULL;
		  
		  if (mem_chunk->type == G_ALLOC_AND_FREE)
		    g_tree_remove (mem_chunk->mem_tree, mem_area);
		  g_free (mem_area);
		}
	    }
	  else
	    {
	      prev_free_atom = temp_free_atom;
	      temp_free_atom = temp_free_atom->next;
	    }
	}
    }
  LEAVE_MEM_CHUNK_ROUTINE ();
}

void
g_mem_chunk_reset (GMemChunk *mem_chunk)
{
  GMemArea *mem_areas;
  GMemArea *temp_area;
  
  g_return_if_fail (mem_chunk != NULL);
  
  ENTER_MEM_CHUNK_ROUTINE ();

  mem_areas = mem_chunk->mem_areas;
  mem_chunk->num_mem_areas = 0;
  mem_chunk->mem_areas = NULL;
  mem_chunk->mem_area = NULL;
  
  while (mem_areas)
    {
      temp_area = mem_areas;
      mem_areas = mem_areas->next;
      g_free (temp_area);
    }
  
  mem_chunk->free_atoms = NULL;
  
  if (mem_chunk->mem_tree)
    {
      g_tree_destroy (mem_chunk->mem_tree);
      mem_chunk->mem_tree = g_tree_new ((GCompareFunc) g_mem_chunk_area_compare);
    }

  LEAVE_MEM_CHUNK_ROUTINE ();
}

void
g_mem_chunk_print (GMemChunk *mem_chunk)
{
  GMemArea *mem_areas;
  gulong mem;
  
  g_return_if_fail (mem_chunk != NULL);
  
  mem_areas = mem_chunk->mem_areas;
  mem = 0;
  
  while (mem_areas)
    {
      mem += mem_chunk->area_size - mem_areas->free;
      mem_areas = mem_areas->next;
    }

  g_log (G_LOG_DOMAIN, G_LOG_LEVEL_INFO,
	 "%s: %ld bytes using %d mem areas",
	 mem_chunk->name, mem, mem_chunk->num_mem_areas);
}

void
g_mem_chunk_info (void)
{
  GMemChunk *mem_chunk;
  gint count;
  
  count = 0;
  g_mutex_lock (mem_chunks_lock);
  mem_chunk = mem_chunks;
  while (mem_chunk)
    {
      count += 1;
      mem_chunk = mem_chunk->next;
    }
  g_mutex_unlock (mem_chunks_lock);
  
  g_log (G_LOG_DOMAIN, G_LOG_LEVEL_INFO, "%d mem chunks", count);
  
  g_mutex_lock (mem_chunks_lock);
  mem_chunk = mem_chunks;
  g_mutex_unlock (mem_chunks_lock);

  while (mem_chunk)
    {
      g_mem_chunk_print ((GMemChunk*) mem_chunk);
      mem_chunk = mem_chunk->next;
    }  
}

void
g_blow_chunks (void)
{
  GMemChunk *mem_chunk;
  
  g_mutex_lock (mem_chunks_lock);
  mem_chunk = mem_chunks;
  g_mutex_unlock (mem_chunks_lock);
  while (mem_chunk)
    {
      g_mem_chunk_clean ((GMemChunk*) mem_chunk);
      mem_chunk = mem_chunk->next;
    }
}

static gulong
g_mem_chunk_compute_size (gulong size,
			  gulong min_size)
{
  gulong power_of_2;
  gulong lower, upper;
  
  power_of_2 = 16;
  while (power_of_2 < size)
    power_of_2 <<= 1;
  
  lower = power_of_2 >> 1;
  upper = power_of_2;
  
  if (size - lower < upper - size && lower >= min_size)
    return lower;
  else
    return upper;
}

static gint
g_mem_chunk_area_compare (GMemArea *a,
			  GMemArea *b)
{
  if (a->mem > b->mem)
    return 1;
  else if (a->mem < b->mem)
    return -1;
  return 0;
}

static gint
g_mem_chunk_area_search (GMemArea *a,
			 gchar    *addr)
{
  if (a->mem <= addr)
    {
      if (addr < &a->mem[a->index])
	return 0;
      return 1;
    }
  return -1;
}

#else /* DISABLE_MEM_POOLS */

typedef struct {
  guint alloc_size;           /* the size of an atom */
}  GMinimalMemChunk;

GMemChunk*
g_mem_chunk_new (const gchar  *name,
		 gint          atom_size,
		 gulong        area_size,
		 gint          type)
{
  GMinimalMemChunk *mem_chunk;

  g_return_val_if_fail (atom_size > 0, NULL);

  mem_chunk = g_new (GMinimalMemChunk, 1);
  mem_chunk->alloc_size = atom_size;

  return ((GMemChunk*) mem_chunk);
}

void
g_mem_chunk_destroy (GMemChunk *mem_chunk)
{
  g_return_if_fail (mem_chunk != NULL);
  
  g_free (mem_chunk);
}

gpointer
g_mem_chunk_alloc (GMemChunk *mem_chunk)
{
  GMinimalMemChunk *minimal = (GMinimalMemChunk *)mem_chunk;
  
  g_return_val_if_fail (mem_chunk != NULL, NULL);
  
  return g_malloc (minimal->alloc_size);
}

gpointer
g_mem_chunk_alloc0 (GMemChunk *mem_chunk)
{
  GMinimalMemChunk *minimal = (GMinimalMemChunk *)mem_chunk;
  
  g_return_val_if_fail (mem_chunk != NULL, NULL);
  
  return g_malloc0 (minimal->alloc_size);
}

void
g_mem_chunk_free (GMemChunk *mem_chunk,
		  gpointer   mem)
{
  g_return_if_fail (mem_chunk != NULL);
  
  g_free (mem);
}

void	g_mem_chunk_clean	(GMemChunk *mem_chunk)	{}
void	g_mem_chunk_reset	(GMemChunk *mem_chunk)	{}
void	g_mem_chunk_print	(GMemChunk *mem_chunk)	{}
void	g_mem_chunk_info	(void)			{}
void	g_blow_chunks		(void)			{}

#endif /* DISABLE_MEM_POOLS */


/* generic allocators
 */
struct _GAllocator /* from gmem.c */
{
  gchar		*name;
  guint16	 n_preallocs;
  guint		 is_unused : 1;
  guint		 type : 4;
  GAllocator	*last;
  GMemChunk	*mem_chunk;
  gpointer	 dummy; /* implementation specific */
};

GAllocator*
g_allocator_new (const gchar *name,
		 guint        n_preallocs)
{
  GAllocator *allocator;

  g_return_val_if_fail (name != NULL, NULL);

  allocator = g_new0 (GAllocator, 1);
  allocator->name = g_strdup (name);
  allocator->n_preallocs = CLAMP (n_preallocs, 1, 65535);
  allocator->is_unused = TRUE;
  allocator->type = 0;
  allocator->last = NULL;
  allocator->mem_chunk = NULL;
  allocator->dummy = NULL;

  return allocator;
}

void
g_allocator_free (GAllocator *allocator)
{
  g_return_if_fail (allocator != NULL);
  g_return_if_fail (allocator->is_unused == TRUE);

  g_free (allocator->name);
  if (allocator->mem_chunk)
    g_mem_chunk_destroy (allocator->mem_chunk);

  g_free (allocator);
}

void
g_mem_init (void)
{
#ifndef DISABLE_MEM_POOLS
  mem_chunks_lock = g_mutex_new ();
#endif
#ifndef G_DISABLE_CHECKS
  mem_chunk_recursion = g_private_new (NULL);
  g_profile_mutex = g_mutex_new ();
#endif
}