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Diffstat (limited to 'glib/gmem.c')
| -rw-r--r-- | glib/gmem.c | 824 |
1 files changed, 824 insertions, 0 deletions
diff --git a/glib/gmem.c b/glib/gmem.c new file mode 100644 index 0000000000..35dfdaba37 --- /dev/null +++ b/glib/gmem.c @@ -0,0 +1,824 @@ +/* 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; +} |