gmem.c

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	   local_mc_allocs,
	   local_mc_frees,
	   ((gdouble) local_mc_frees) / local_mc_allocs * 100.0,
	   local_mc_allocs - local_mc_frees);
}

static gpointer
profiler_try_malloc (gsize n_bytes)
{
  gulong *p;

#ifdef  G_ENABLE_DEBUG
  if (g_trap_malloc_size == n_bytes)
    G_BREAKPOINT ();
#endif  /* G_ENABLE_DEBUG */

  p = standard_malloc (sizeof (gulong) * 2 + n_bytes);

  if (p)
    {
      p[0] = 0;		/* free count */
      p[1] = n_bytes;	/* length */
      profiler_log (PROFILER_ALLOC, n_bytes, TRUE);
      p += 2;
    }
  else
    profiler_log (PROFILER_ALLOC, n_bytes, FALSE);
  
  return p;
}

static gpointer
profiler_malloc (gsize n_bytes)
{
  gpointer mem = profiler_try_malloc (n_bytes);

  if (!mem)
    g_mem_profile ();

  return mem;
}

static gpointer
profiler_calloc (gsize n_blocks,
		 gsize n_block_bytes)
{
  gsize l = n_blocks * n_block_bytes;
  gulong *p;

#ifdef  G_ENABLE_DEBUG
  if (g_trap_malloc_size == l)
    G_BREAKPOINT ();
#endif  /* G_ENABLE_DEBUG */
  
  p = standard_calloc (1, sizeof (gulong) * 2 + l);

  if (p)
    {
      p[0] = 0;		/* free count */
      p[1] = l;		/* length */
      profiler_log (PROFILER_ALLOC | PROFILER_ZINIT, l, TRUE);
      p += 2;
    }
  else
    {
      profiler_log (PROFILER_ALLOC | PROFILER_ZINIT, l, FALSE);
      g_mem_profile ();
    }

  return p;
}

static void
profiler_free (gpointer mem)
{
  gulong *p = mem;

  p -= 2;
  if (p[0])	/* free count */
    {
      g_warning ("free(%p): memory has been freed %lu times already", p + 2, p[0]);
      profiler_log (PROFILER_FREE,
		    p[1],	/* length */
		    FALSE);
    }
  else
    {
#ifdef  G_ENABLE_DEBUG
      if (g_trap_free_size == p[1])
	G_BREAKPOINT ();
#endif  /* G_ENABLE_DEBUG */

      profiler_log (PROFILER_FREE,
		    p[1],	/* length */
		    TRUE);
      memset (p + 2, 0xaa, p[1]);

      /* for all those that miss standard_free (p); in this place, yes,
       * we do leak all memory when profiling, and that is intentional
       * to catch double frees. patch submissions are futile.
       */
    }
  p[0] += 1;
}

static gpointer
profiler_try_realloc (gpointer mem,
		      gsize    n_bytes)
{
  gulong *p = mem;

  p -= 2;

#ifdef  G_ENABLE_DEBUG
  if (g_trap_realloc_size == n_bytes)
    G_BREAKPOINT ();
#endif  /* G_ENABLE_DEBUG */
  
  if (mem && p[0])	/* free count */
    {
      g_warning ("realloc(%p, %lu): memory has been freed %lu times already", p + 2, (gulong)n_bytes, p[0]);
      profiler_log (PROFILER_ALLOC | PROFILER_RELOC, n_bytes, FALSE);

      return NULL;
    }
  else
    {
      p = standard_realloc (mem ? p : NULL, sizeof (gulong) * 2 + n_bytes);

      if (p)
	{
	  if (mem)
	    profiler_log (PROFILER_FREE | PROFILER_RELOC, p[1], TRUE);
	  p[0] = 0;
	  p[1] = n_bytes;
	  profiler_log (PROFILER_ALLOC | PROFILER_RELOC, p[1], TRUE);
	  p += 2;
	}
      else
	profiler_log (PROFILER_ALLOC | PROFILER_RELOC, n_bytes, FALSE);

      return p;
    }
}

static gpointer
profiler_realloc (gpointer mem,
		  gsize    n_bytes)
{
  mem = profiler_try_realloc (mem, n_bytes);

  if (!mem)
    g_mem_profile ();

  return mem;
}

static GMemVTable profiler_table = {
  profiler_malloc,
  profiler_realloc,
  profiler_free,
  profiler_calloc,
  profiler_try_malloc,
  profiler_try_realloc,
};
GMemVTable *glib_mem_profiler_table = &profiler_table;

#endif	/* !G_DISABLE_CHECKS */


/* --- MemChunks --- */
typedef struct _GFreeAtom      GFreeAtom;
typedef struct _GMemArea       GMemArea;

struct _GFreeAtom
{
  GFreeAtom *next;
};

struct _GMemArea
{
  GMemArea *next;            /* the next mem area */
  GMemArea *prev;            /* the previous mem area */
  gulong index;              /* the current index into the "mem" array */
  gulong free;               /* the number of free bytes in this mem area */
  gulong allocated;          /* the number of atoms allocated from this area */
  gulong mark;               /* is this mem area marked for deletion */
  gchar mem[MEM_AREA_SIZE];  /* the mem array from which atoms get allocated
			      * the actual size of this array is determined by
			      *  the mem chunk "area_size". ANSI says that it
			      *  must be declared to be the maximum size it
			      *  can possibly be (even though the actual size
			      *  may be less).
			      */
};

struct _GMemChunk
{
  const gchar *name;         /* name of this MemChunk...used for debugging output */
  gint type;                 /* the type of MemChunk: ALLOC_ONLY or ALLOC_AND_FREE */
  gint num_mem_areas;        /* the number of memory areas */
  gint num_marked_areas;     /* the number of areas marked for deletion */
  guint atom_size;           /* the size of an atom */
  gulong area_size;          /* the size of a memory area */
  GMemArea *mem_area;        /* the current memory area */
  GMemArea *mem_areas;       /* a list of all the mem areas owned by this chunk */
  GMemArea *free_mem_area;   /* the free area...which is about to be destroyed */
  GFreeAtom *free_atoms;     /* the free atoms list */
  GTree *mem_tree;           /* tree of mem areas sorted by memory address */
  GMemChunk *next;           /* pointer to the next chunk */
  GMemChunk *prev;           /* pointer to the previous chunk */
};


#ifndef DISABLE_MEM_POOLS
static gulong g_mem_chunk_compute_size (gulong    size,
					gulong    min_size) G_GNUC_CONST;
static gint   g_mem_chunk_area_compare (GMemArea *a,
					GMemArea *b);
static gint   g_mem_chunk_area_search  (GMemArea *a,
					gchar    *addr);

/* here we can't use StaticMutexes, as they depend upon a working
 * g_malloc, the same holds true for StaticPrivate
 */
static GMutex        *mem_chunks_lock = NULL;
static GMemChunk     *mem_chunks = NULL;

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

  g_return_val_if_fail (atom_size > 0, NULL);
  g_return_val_if_fail (area_size >= atom_size, NULL);

  ENTER_MEM_CHUNK_ROUTINE ();

  area_size = (area_size + atom_size - 1) / atom_size;
  area_size *= atom_size;

  mem_chunk = g_new (GMemChunk, 1);
  mem_chunk->name = name;
  mem_chunk->type = type;
  mem_chunk->num_mem_areas = 0;
  mem_chunk->num_marked_areas = 0;
  mem_chunk->mem_area = NULL;
  mem_chunk->free_mem_area = NULL;
  mem_chunk->free_atoms = NULL;
  mem_chunk->mem_tree = NULL;
  mem_chunk->mem_areas = NULL;
  mem_chunk->atom_size = atom_size;
  
  if (mem_chunk->type == G_ALLOC_AND_FREE)
    mem_chunk->mem_tree = g_tree_new ((GCompareFunc) g_mem_chunk_area_compare);
  
  if (mem_chunk->atom_size % G_MEM_ALIGN)
    mem_chunk->atom_size += G_MEM_ALIGN - (mem_chunk->atom_size % G_MEM_ALIGN);

  rarea_size = area_size + sizeof (GMemArea) - MEM_AREA_SIZE;
  rarea_size = g_mem_chunk_compute_size (rarea_size, atom_size + sizeof (GMemArea) - MEM_AREA_SIZE);
  mem_chunk->area_size = rarea_size - (sizeof (GMemArea) - MEM_AREA_SIZE);

  g_mutex_lock (mem_chunks_lock);
  mem_chunk->next = mem_chunks;
  mem_chunk->prev = NULL;
  if (mem_chunks)
    mem_chunks->prev = mem_chunk;
  mem_chunks = mem_chunk;
  g_mutex_unlock (mem_chunks_lock);

  LEAVE_MEM_CHUNK_ROUTINE ();

  return mem_chunk;
}

void
g_mem_chunk_destroy (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;
  while (mem_areas)
    {
      temp_area = mem_areas;
      mem_areas = mem_areas->next;
      g_free (temp_area);
    }
  
  if (mem_chunk->next)
    mem_chunk->next->prev = mem_chunk->prev;
  if (mem_chunk->prev)
    mem_chunk->prev->next = mem_chunk->next;
  
  g_mutex_lock (mem_chunks_lock);
  if (mem_chunk == mem_chunks)
    mem_chunks = mem_chunks->next;
  g_mutex_unlock (mem_chunks_lock);
  
  if (mem_chunk->type == G_ALLOC_AND_FREE)
    g_tree_destroy (mem_chunk->mem_tree);  

  g_free (mem_chunk);

  LEAVE_MEM_CHUNK_ROUTINE ();
}

gpointer
g_mem_chunk_alloc (GMemChunk *mem_chunk)
{
  GMemArea *temp_area;
  gpointer mem;

  ENTER_MEM_CHUNK_ROUTINE ();

  g_return_val_if_fail (mem_chunk != NULL, NULL);
  
  while (mem_chunk->free_atoms)
    {
      /* Get the first piece of memory on the "free_atoms" list.
       * We can go ahead and destroy the list node we used to keep
       *  track of it with and to update the "free_atoms" list to
       *  point to its next element.
       */
      mem = mem_chunk->free_atoms;
      mem_chunk->free_atoms = mem_chunk->free_atoms->next;
      
      /* Determine which area this piece of memory is allocated from */
      temp_area = g_tree_search (mem_chunk->mem_tree,
				 (GCompareFunc) g_mem_chunk_area_search,
				 mem);
      
      /* If the area has been marked, then it is being destroyed.
       *  (ie marked to be destroyed).
       * We check to see if all of the segments on the free list that
       *  reference this area have been removed. This occurs when
       *  the ammount of free memory is less than the allocatable size.
       * If the chunk should be freed, then we place it in the "free_mem_area".
       * This is so we make sure not to free the mem area here and then
       *  allocate it again a few lines down.
       * If we don't allocate a chunk a few lines down then the "free_mem_area"
       *  will be freed.
       * If there is already a "free_mem_area" then we'll just free this mem area.
       */
      if (temp_area->mark)
        {
          /* Update the "free" memory available in that area */
          temp_area->free += mem_chunk->atom_size;
	  
          if (temp_area->free == mem_chunk->area_size)
            {
              if (temp_area == mem_chunk->mem_area)
                mem_chunk->mem_area = NULL;
	      
              if (mem_chunk->free_mem_area)
                {
                  mem_chunk->num_mem_areas -= 1;
		  
                  if (temp_area->next)
                    temp_area->next->prev = temp_area->prev;
                  if (temp_area->prev)
                    temp_area->prev->next = temp_area->next;
                  if (temp_area == mem_chunk->mem_areas)
                    mem_chunk->mem_areas = mem_chunk->mem_areas->next;
		  
		  if (mem_chunk->type == G_ALLOC_AND_FREE)
		    g_tree_remove (mem_chunk->mem_tree, temp_area);
                  g_free (temp_area);
                }
              else
                mem_chunk->free_mem_area = temp_area;
	      
	      mem_chunk->num_marked_areas -= 1;
	    }
	}
      else
        {
          /* Update the number of allocated atoms count.
	   */
          temp_area->allocated += 1;
	  
          /* The area wasn't marked...return the memory
	   */
	  goto outa_here;
        }
    }
  
  /* If there isn't a current mem area or the current mem area is out of space
   *  then allocate a new mem area. We'll first check and see if we can use
   *  the "free_mem_area". Otherwise we'll just malloc the mem area.
   */
  if ((!mem_chunk->mem_area) ||
      ((mem_chunk->mem_area->index + mem_chunk->atom_size) > mem_chunk->area_size))
    {
      if (mem_chunk->free_mem_area)
        {
          mem_chunk->mem_area = mem_chunk->free_mem_area;
	  mem_chunk->free_mem_area = NULL;
        }
      else
        {
#ifdef ENABLE_GC_FRIENDLY
	  mem_chunk->mem_area = (GMemArea*) g_malloc0 (sizeof (GMemArea) -
						       MEM_AREA_SIZE +
						       mem_chunk->area_size); 
#else /* !ENABLE_GC_FRIENDLY */
	  mem_chunk->mem_area = (GMemArea*) g_malloc (sizeof (GMemArea) -
						      MEM_AREA_SIZE +
						      mem_chunk->area_size);
#endif /* ENABLE_GC_FRIENDLY */
	  
	  mem_chunk->num_mem_areas += 1;
	  mem_chunk->mem_area->next = mem_chunk->mem_areas;
	  mem_chunk->mem_area->prev = NULL;