gtk2/glib/gmem.c
1997-11-24 22:37:52 +00:00

825 lines
20 KiB
C

/* GLIB - Library of useful routines for C programming
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <stdlib.h>
#include <string.h>
#include "glib.h"
/* #define MEM_PROFILE */
/* #define MEM_CHECK */
#define MAX_MEM_AREA 65536L
#define MEM_AREA_SIZE 4L
#if SIZEOF_VOID_P > SIZEOF_LONG
#define MEM_ALIGN SIZEOF_VOID_P
#else
#define MEM_ALIGN SIZEOF_LONG
#endif
typedef struct _GFreeAtom GFreeAtom;
typedef struct _GMemArea GMemArea;
typedef struct _GRealMemChunk GRealMemChunk;
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 _GRealMemChunk
{
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 */
GRealMemChunk *next; /* pointer to the next chunk */
GRealMemChunk *prev; /* pointer to the previous chunk */
};
static gulong g_mem_chunk_compute_size (gulong size);
static gint g_mem_chunk_area_compare (GMemArea *a,
GMemArea *b);
static gint g_mem_chunk_area_search (GMemArea *a,
gchar *addr);
static GRealMemChunk *mem_chunks = NULL;
#ifdef MEM_PROFILE
static gulong allocations[4096] = { 0 };
static gulong allocated_mem = 0;
static gulong freed_mem = 0;
#endif /* MEM_PROFILE */
#ifndef USE_DMALLOC
gpointer
g_malloc (gulong size)
{
gpointer p;
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
gulong *t;
#endif /* MEM_PROFILE || MEM_CHECK */
if (size == 0)
return NULL;
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
size += SIZEOF_LONG;
#endif /* MEM_PROFILE || MEM_CHECK */
#ifdef MEM_CHECK
size += SIZEOF_LONG;
#endif /* MEM_CHECK */
p = (gpointer) malloc (size);
if (!p)
g_error ("could not allocate %ld bytes", size);
#ifdef MEM_CHECK
size -= SIZEOF_LONG;
t = p;
p = ((guchar*) p + SIZEOF_LONG);
*t = 0;
#endif /* MEM_CHECK */
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
size -= SIZEOF_LONG;
t = p;
p = ((guchar*) p + SIZEOF_LONG);
*t = size;
#ifdef MEM_PROFILE
if (size <= 4095)
allocations[size-1] += 1;
else
allocations[4095] += 1;
allocated_mem += size;
#endif /* MEM_PROFILE */
#endif /* MEM_PROFILE || MEM_CHECK */
return p;
}
gpointer
g_malloc0 (gulong size)
{
gpointer p;
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
gulong *t;
#endif /* MEM_PROFILE || MEM_CHECK */
if (size == 0)
return NULL;
#ifdef MEM_PROFILE
size += SIZEOF_LONG;
#endif /* MEM_PROFILE */
#ifdef MEM_CHECK
size += SIZEOF_LONG;
#endif /* MEM_CHECK */
p = (gpointer) calloc (size, 1);
if (!p)
g_error ("could not allocate %ld bytes", size);
#ifdef MEM_CHECK
size -= SIZEOF_LONG;
t = p;
p = ((guchar*) p + SIZEOF_LONG);
*t = 0;
#endif /* MEM_CHECK */
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
size -= SIZEOF_LONG;
t = p;
p = ((guchar*) p + SIZEOF_LONG);
*t = size;
#ifdef MEM_PROFILE
if (size <= 4095)
allocations[size-1] += 1;
else
allocations[4095] += 1;
allocated_mem += size;
#endif /* MEM_PROFILE */
#endif /* MEM_PROFILE */
return p;
}
gpointer
g_realloc (gpointer mem,
gulong size)
{
gpointer p;
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
gulong *t;
#endif /* MEM_PROFILE || MEM_CHECK */
if (size == 0)
return NULL;
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
size += SIZEOF_LONG;
#endif /* MEM_PROFILE || MEM_CHECK */
#ifdef MEM_CHECK
size += SIZEOF_LONG;
#endif /* MEM_CHECK */
if (!mem)
p = (gpointer) malloc (size);
else
{
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
t = (gulong*) ((guchar*) mem - SIZEOF_LONG);
#ifdef MEM_PROFILE
freed_mem += *t;
#endif /* MEM_PROFILE */
mem = t;
#endif /* MEM_PROFILE || MEM_CHECK */
#ifdef MEM_CHECK
t = (gulong*) ((guchar*) mem - SIZEOF_LONG);
if (*t >= 1)
g_warning ("trying to realloc freed memory\n");
mem = t;
#endif /* MEM_CHECK */
p = (gpointer) realloc (mem, size);
}
if (!p)
g_error ("could not reallocate %ld bytes", size);
#ifdef MEM_CHECK
size -= SIZEOF_LONG;
t = p;
p = ((guchar*) p + SIZEOF_LONG);
*t = 0;
#endif /* MEM_CHECK */
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
size -= SIZEOF_LONG;
t = p;
p = ((guchar*) p + SIZEOF_LONG);
*t = size;
#ifdef MEM_PROFILE
if (size <= 4095)
allocations[size-1] += 1;
else
allocations[4095] += 1;
allocated_mem += size;
#endif /* MEM_PROFILE */
#endif /* MEM_PROFILE || MEM_CHECK */
return p;
}
void
g_free (gpointer mem)
{
if (mem)
{
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
gulong *t;
gulong size;
#endif /* MEM_PROFILE || MEM_CHECK */
#if defined(MEM_PROFILE) || defined(MEM_CHECK)
t = (gulong*) ((guchar*) mem - SIZEOF_LONG);
size = *t;
#ifdef MEM_PROFILE
freed_mem += size;
#endif /* MEM_PROFILE */
mem = t;
#endif /* MEM_PROFILE || MEM_CHECK */
#ifdef MEM_CHECK
t = (gulong*) ((guchar*) mem - SIZEOF_LONG);
if (*t >= 1)
g_warning ("freeing previously freed memory\n");
*t += 1;
mem = t;
memset ((guchar*) mem + 8, 0, size);
#else /* MEM_CHECK */
free (mem);
#endif /* MEM_CHECK */
}
}
#endif /* ! USE_DMALLOC */
void
g_mem_profile ()
{
#ifdef MEM_PROFILE
gint i;
for (i = 0; i < 4095; i++)
if (allocations[i] > 0)
g_print ("%lu allocations of %d bytes\n", allocations[i], i + 1);
if (allocations[4095] > 0)
g_print ("%lu allocations of greater than 4095 bytes\n", allocations[4095]);
g_print ("%lu bytes allocated\n", allocated_mem);
g_print ("%lu bytes freed\n", freed_mem);
g_print ("%lu bytes in use\n", allocated_mem - freed_mem);
#endif /* MEM_PROFILE */
}
void
g_mem_check (gpointer mem)
{
#ifdef MEM_CHECK
gulong *t;
t = (gulong*) ((guchar*) mem - SIZEOF_LONG - SIZEOF_LONG);
if (*t >= 1)
g_warning ("mem: 0x%08x has been freed: %lu\n", (gulong) mem, *t);
#endif /* MEM_CHECK */
}
GMemChunk*
g_mem_chunk_new (gchar *name,
gint atom_size,
gulong area_size,
gint type)
{
GRealMemChunk *mem_chunk;
gulong rarea_size;
mem_chunk = g_new (struct _GRealMemChunk, 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 % MEM_ALIGN)
mem_chunk->atom_size += MEM_ALIGN - (mem_chunk->atom_size % MEM_ALIGN);
mem_chunk->area_size = area_size;
if (mem_chunk->area_size > MAX_MEM_AREA)
mem_chunk->area_size = MAX_MEM_AREA;
while (mem_chunk->area_size < mem_chunk->atom_size)
mem_chunk->area_size *= 2;
rarea_size = mem_chunk->area_size + sizeof (GMemArea) - MEM_AREA_SIZE;
rarea_size = g_mem_chunk_compute_size (rarea_size);
mem_chunk->area_size = rarea_size - (sizeof (GMemArea) - MEM_AREA_SIZE);
/*
mem_chunk->area_size -= (sizeof (GMemArea) - MEM_AREA_SIZE);
if (mem_chunk->area_size < mem_chunk->atom_size)
{
mem_chunk->area_size = (mem_chunk->area_size + sizeof (GMemArea) - MEM_AREA_SIZE) * 2;
mem_chunk->area_size -= (sizeof (GMemArea) - MEM_AREA_SIZE);
}
if (mem_chunk->area_size % mem_chunk->atom_size)
mem_chunk->area_size += mem_chunk->atom_size - (mem_chunk->area_size % mem_chunk->atom_size);
*/
mem_chunk->next = mem_chunks;
mem_chunk->prev = NULL;
if (mem_chunks)
mem_chunks->prev = mem_chunk;
mem_chunks = mem_chunk;
return ((GMemChunk*) mem_chunk);
}
void
g_mem_chunk_destroy (GMemChunk *mem_chunk)
{
GRealMemChunk *rmem_chunk;
GMemArea *mem_areas;
GMemArea *temp_area;
g_assert (mem_chunk != NULL);
rmem_chunk = (GRealMemChunk*) mem_chunk;
mem_areas = rmem_chunk->mem_areas;
while (mem_areas)
{
temp_area = mem_areas;
mem_areas = mem_areas->next;
g_free (temp_area);
}
if (rmem_chunk->next)
rmem_chunk->next->prev = rmem_chunk->prev;
if (rmem_chunk->prev)
rmem_chunk->prev->next = rmem_chunk->next;
if (rmem_chunk == mem_chunks)
mem_chunks = mem_chunks->next;
if (rmem_chunk->type == G_ALLOC_AND_FREE)
g_tree_destroy (rmem_chunk->mem_tree);
g_free (rmem_chunk);
}
gpointer
g_mem_chunk_alloc (GMemChunk *mem_chunk)
{
GRealMemChunk *rmem_chunk;
GMemArea *temp_area;
gpointer mem;
g_assert (mem_chunk != NULL);
rmem_chunk = (GRealMemChunk*) mem_chunk;
while (rmem_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 = rmem_chunk->free_atoms;
rmem_chunk->free_atoms = rmem_chunk->free_atoms->next;
/* Determine which area this piece of memory is allocated from */
temp_area = g_tree_search (rmem_chunk->mem_tree,
(GSearchFunc) 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 += rmem_chunk->atom_size;
if (temp_area->free == rmem_chunk->area_size)
{
if (temp_area == rmem_chunk->mem_area)
rmem_chunk->mem_area = NULL;
if (rmem_chunk->free_mem_area)
{
rmem_chunk->num_mem_areas -= 1;
rmem_chunk->num_marked_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 == rmem_chunk->mem_areas)
rmem_chunk->mem_areas = rmem_chunk->mem_areas->next;
if (temp_area == rmem_chunk->mem_area)
rmem_chunk->mem_area = NULL;
g_free (temp_area);
}
else
rmem_chunk->free_mem_area = temp_area;
}
}
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 ((!rmem_chunk->mem_area) ||
((rmem_chunk->mem_area->index + rmem_chunk->atom_size) > rmem_chunk->area_size))
{
if (rmem_chunk->free_mem_area)
{
rmem_chunk->mem_area = rmem_chunk->free_mem_area;
rmem_chunk->free_mem_area = NULL;
}
else
{
rmem_chunk->mem_area = (GMemArea*) g_malloc (sizeof (GMemArea) -
MEM_AREA_SIZE +
rmem_chunk->area_size);
rmem_chunk->num_mem_areas += 1;
rmem_chunk->mem_area->next = rmem_chunk->mem_areas;
rmem_chunk->mem_area->prev = NULL;
if (rmem_chunk->mem_areas)
rmem_chunk->mem_areas->prev = rmem_chunk->mem_area;
rmem_chunk->mem_areas = rmem_chunk->mem_area;
if (rmem_chunk->type == G_ALLOC_AND_FREE)
g_tree_insert (rmem_chunk->mem_tree, rmem_chunk->mem_area, rmem_chunk->mem_area);
}
rmem_chunk->mem_area->index = 0;
rmem_chunk->mem_area->free = rmem_chunk->area_size;
rmem_chunk->mem_area->allocated = 0;
rmem_chunk->mem_area->mark = 0;
}
else if (rmem_chunk->free_mem_area)
{
rmem_chunk->num_mem_areas -= 1;
if (rmem_chunk->free_mem_area->next)
rmem_chunk->free_mem_area->next->prev = rmem_chunk->free_mem_area->prev;
if (rmem_chunk->free_mem_area->prev)
rmem_chunk->free_mem_area->prev->next = rmem_chunk->free_mem_area->next;
if (rmem_chunk->free_mem_area == rmem_chunk->mem_areas)
rmem_chunk->mem_areas = rmem_chunk->mem_areas->next;
if (rmem_chunk->type == G_ALLOC_AND_FREE)
g_tree_remove (rmem_chunk->mem_tree, rmem_chunk->free_mem_area);
g_free (rmem_chunk->free_mem_area);
rmem_chunk->free_mem_area = NULL;
}
/* Get the memory and modify the state variables appropriately.
*/
mem = (gpointer) &rmem_chunk->mem_area->mem[rmem_chunk->mem_area->index];
rmem_chunk->mem_area->index += rmem_chunk->atom_size;
rmem_chunk->mem_area->free -= rmem_chunk->atom_size;
rmem_chunk->mem_area->allocated += 1;
outa_here:
return mem;
}
void
g_mem_chunk_free (GMemChunk *mem_chunk,
gpointer mem)
{
GRealMemChunk *rmem_chunk;
GMemArea *temp_area;
GFreeAtom *free_atom;
g_assert (mem_chunk != NULL);
g_assert (mem != NULL);
rmem_chunk = (GRealMemChunk*) mem_chunk;
/* Don't do anything if this is an ALLOC_ONLY chunk
*/
if (rmem_chunk->type == G_ALLOC_AND_FREE)
{
/* Place the memory on the "free_atoms" list
*/
free_atom = (GFreeAtom*) mem;
free_atom->next = rmem_chunk->free_atoms;
rmem_chunk->free_atoms = free_atom;
temp_area = g_tree_search (rmem_chunk->mem_tree,
(GSearchFunc) g_mem_chunk_area_search,
mem);
temp_area->allocated -= 1;
if (temp_area->allocated == 0)
{
temp_area->mark = 1;
rmem_chunk->num_marked_areas += 1;
g_mem_chunk_clean (mem_chunk);
}
}
}
void
g_mem_chunk_clean (GMemChunk *mem_chunk)
{
GRealMemChunk *rmem_chunk;
GMemArea *mem_area;
GFreeAtom *prev_free_atom;
GFreeAtom *temp_free_atom;
gpointer mem;
g_assert (mem_chunk != NULL);
rmem_chunk = (GRealMemChunk*) mem_chunk;
if (rmem_chunk->type == G_ALLOC_AND_FREE)
{
prev_free_atom = NULL;
temp_free_atom = rmem_chunk->free_atoms;
while (temp_free_atom)
{
mem = (gpointer) temp_free_atom;
mem_area = g_tree_search (rmem_chunk->mem_tree,
(GSearchFunc) 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
rmem_chunk->free_atoms = temp_free_atom->next;
temp_free_atom = temp_free_atom->next;
mem_area->free += rmem_chunk->atom_size;
if (mem_area->free == rmem_chunk->area_size)
{
rmem_chunk->num_mem_areas -= 1;
rmem_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 == rmem_chunk->mem_areas)
rmem_chunk->mem_areas = rmem_chunk->mem_areas->next;
if (mem_area == rmem_chunk->mem_area)
rmem_chunk->mem_area = NULL;
if (rmem_chunk->type == G_ALLOC_AND_FREE)
g_tree_remove (rmem_chunk->mem_tree, mem_area);
g_free (mem_area);
}
}
else
{
prev_free_atom = temp_free_atom;
temp_free_atom = temp_free_atom->next;
}
}
}
}
void
g_mem_chunk_reset (GMemChunk *mem_chunk)
{
GRealMemChunk *rmem_chunk;
GMemArea *mem_areas;
GMemArea *temp_area;
g_assert (mem_chunk != NULL);
rmem_chunk = (GRealMemChunk*) mem_chunk;
mem_areas = rmem_chunk->mem_areas;
rmem_chunk->num_mem_areas = 0;
rmem_chunk->mem_areas = NULL;
rmem_chunk->mem_area = NULL;
while (mem_areas)
{
temp_area = mem_areas;
mem_areas = mem_areas->next;
g_free (temp_area);
}
rmem_chunk->free_atoms = NULL;
if (rmem_chunk->mem_tree)
g_tree_destroy (rmem_chunk->mem_tree);
rmem_chunk->mem_tree = g_tree_new ((GCompareFunc) g_mem_chunk_area_compare);
}
void
g_mem_chunk_print (GMemChunk *mem_chunk)
{
GRealMemChunk *rmem_chunk;
GMemArea *mem_areas;
gulong mem;
g_assert (mem_chunk != NULL);
rmem_chunk = (GRealMemChunk*) mem_chunk;
mem_areas = rmem_chunk->mem_areas;
mem = 0;
while (mem_areas)
{
mem += rmem_chunk->area_size - mem_areas->free;
mem_areas = mem_areas->next;
}
g_print ("%s: %ld bytes using %d mem areas", rmem_chunk->name, mem, rmem_chunk->num_mem_areas);
}
void
g_mem_chunk_info ()
{
GRealMemChunk *mem_chunk;
gint count;
count = 0;
mem_chunk = mem_chunks;
while (mem_chunk)
{
count += 1;
mem_chunk = mem_chunk->next;
}
g_print ("%d mem chunks", count);
mem_chunk = mem_chunks;
while (mem_chunk)
{
g_mem_chunk_print ((GMemChunk*) mem_chunk);
mem_chunk = mem_chunk->next;
}
}
void
g_blow_chunks ()
{
GRealMemChunk *mem_chunk;
mem_chunk = mem_chunks;
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 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))
return lower;
return upper;
}
static gint
g_mem_chunk_area_compare (GMemArea *a,
GMemArea *b)
{
return (a->mem - b->mem);
}
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;
}