some work done on splitting, free() next

This commit is contained in:
Jack Halford 2017-02-16 15:48:29 +01:00
parent 5c78200d8f
commit 053c0773de
6 changed files with 124 additions and 42 deletions

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@ -1,11 +1,14 @@
#ifndef MALLOC_H #ifndef MALLOC_H
# define MALLOC_H # define MALLOC_H
#define malloc_n 20 # define malloc_n 64
#define malloc_m 100 # define malloc_m 512
#define malloc_N 100 # define malloc_N (1 * getpagesize())
#define malloc_M 500 # define malloc_M (2 * getpagesize())
# define malloc_magic 1234567 # define malloc_magic 1234567
# define malloc_realign(x) ((((x) + 1) / 8) * 8)
# define malloc_bytes(x) (((x) + 1) / 8)
# define HEADER_SIZE malloc_bytes(sizeof(t_node))
# define TINY(x) (x < (malloc_n + 1)) # define TINY(x) (x < (malloc_n + 1))
# define SMALL(x) (!TINY(x) && !LARGE(x)) # define SMALL(x) (!TINY(x) && !LARGE(x))
# define LARGE(x) (malloc_m < x) # define LARGE(x) (malloc_m < x)
@ -23,12 +26,15 @@ typedef struct s_node {
struct s_node *next; struct s_node *next;
} t_node; } t_node;
extern t_node *tiny_head; extern t_node *tiny_zone;
extern t_node *small_head; extern t_node *small_zone;
extern t_node *tiny_alloc;
extern t_node *small_alloc;
void free(void *ptr); void free(void *ptr);
void *malloc(size_t size); void *malloc(size_t size);
void *realloc(void *ptr, size_t size); void *realloc(void *ptr, size_t size);
void show_alloc_mem(void); void show_alloc_mem(void);
void show_free_mem(void);
#endif #endif

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@ -4,10 +4,24 @@ int main(void)
{ {
void *ptr; void *ptr;
ptr = malloc(10); printf("pagesize=[%i]\n", getpagesize());
ptr = malloc(42); printf("sizeof(long)=[%lu]\n", sizeof(long));
ptr = malloc(3); printf("sizeof(t_node)=[%lu]\n", sizeof(t_node));
ptr = malloc(15); ptr = malloc(1 * sizeof(long));
show_alloc_mem(); show_alloc_mem();
ft_putchar('\n');
ptr = malloc(84 * sizeof(long));
show_alloc_mem();
ft_putchar('\n');
ptr = malloc(65 * sizeof(long));
show_alloc_mem();
ft_putchar('\n');
ptr = malloc(64 * sizeof(long));
show_alloc_mem();
ft_putchar('\n');
return (0); return (0);
} }

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@ -7,7 +7,7 @@ t_node *small_alloc = NULL;
t_node **find_node(t_node **node, size_t size) t_node **find_node(t_node **node, size_t size)
{ {
while (*node && (size_t)(*node)->size < sizeof(t_header) + size) while (*node && (size_t)(*node)->size < sizeof(t_node) + size)
node = &(*node)->next; node = &(*node)->next;
return (node); return (node);
} }
@ -18,34 +18,57 @@ void add_chunk(t_node **node_ref, size_t size)
node_ref = &(*node_ref)->next; node_ref = &(*node_ref)->next;
*node_ref = mmap(NULL, malloc_N, PROT_READ|PROT_WRITE, *node_ref = mmap(NULL, malloc_N, PROT_READ|PROT_WRITE,
MAP_ANON|MAP_PRIVATE, -1, 0); MAP_ANON|MAP_PRIVATE, -1, 0);
(*node_ref)->size = (TINY(size) ? malloc_N : malloc_M) + sizeof(t_node); (*node_ref)->size = TINY(size) ? malloc_N : malloc_M;
(*node_ref)->next = NULL; (*node_ref)->next = NULL;
} }
void *split_node(t_node **node, size_t size) void mem_insert(t_node **head, t_node *new)
{ {
t_header *hptr; while (*head)
{
if (new < *head)
{
new->next = *head;
*head = new;
return ;
}
head = &(*head)->next;
}
*head = new;
}
void *split_node(t_node **free, t_node **alloc, size_t size)
{
t_node *new_alloc;
int free_size; int free_size;
free_size = (*node)->size; free_size = (*free)->size;
hptr = *(t_header**)node; /* printf("split now size=[%zu]\n", size); */
*node = *node + size + sizeof(*hptr); /* printf("free @ [%p], size=[%i]\n", *free, (*free)->size); */
(*node)->size = free_size - size - sizeof(*hptr); /* printf("size + sizeof = [%lu]\n", size + HEADER_SIZE); */
hptr->size = size; /* printf("alloc @ [%p]\n", *alloc); */
hptr->magic = malloc_magic; /* fflush(stdout); */
return (hptr + sizeof(*hptr)); new_alloc = *free;
*(void**)free += 8 * (size + HEADER_SIZE);
(*free)->size = free_size - (size + HEADER_SIZE);
new_alloc->size = size;
mem_insert(alloc, new_alloc);
return (*alloc + HEADER_SIZE);
} }
void *malloc(size_t size) void *malloc(size_t size)
{ {
t_node **zone_ref; t_node **zone_ref;
t_node **alloc_ref;
t_node **node_ref; t_node **node_ref;
void *ptr; void *ptr;
printf("malloc(%zu) was called\n", size); printf("malloc(%zu) was called. [%lu] bytes\n", size, malloc_bytes(size));
size = malloc_bytes(size);
zone_ref = TINY(size) ? &tiny_zone : &small_zone; zone_ref = TINY(size) ? &tiny_zone : &small_zone;
while (!(*(node_ref = find_node(zone_ref, size)))) alloc_ref = TINY(size) ? &tiny_alloc : &small_alloc;
while (!*(node_ref = find_node(zone_ref, size)))
add_chunk(node_ref, size); add_chunk(node_ref, size);
ptr = split_node(node_ref, size); ptr = split_node(node_ref, alloc_ref, size);
return (ptr); return (ptr);
} }

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@ -2,16 +2,40 @@
t_node *tiny_zone; t_node *tiny_zone;
t_node *small_zone; t_node *small_zone;
t_node *tiny_alloc;
t_node *small_alloc;
int show_free_zone(t_node *node) void print_free_mem(t_node *node)
{
size_t size;
void *addr;
size = node->size;
addr = (void*)node;
printf("\t%p - %p : %4zu byte%c\n",
addr, addr + 8 * size, size, size > 1 ? 's' : 0);
}
void print_alloc_mem(t_node *node)
{
size_t size;
void *addr;
size = node->size;
addr = (void*)node + HEADER_SIZE;
printf("\t%p - %p : %4zu(+%zu) byte%c\n",
addr, addr + 8 * size, size, HEADER_SIZE, size > 1 ? 's' : 0);
}
int show_zone(t_node *node, int is_free)
{ {
int total; int total;
total = 0; total = 0;
while (node) while (node)
{ {
printf("%p - %p: %i bytes\n", node, node + node->size, node->size); is_free ? print_free_mem(node) : print_alloc_mem(node);
total += node->size; total += node->size + HEADER_SIZE;
node = node->next; node = node->next;
} }
return (total); return (total);
@ -19,12 +43,27 @@ int show_free_zone(t_node *node)
void show_alloc_mem(void) void show_alloc_mem(void)
{ {
int total; size_t free_total;
size_t alloc_total;
total = 0; free_total = 0;
ft_putstr("TINY:\n"); alloc_total = 0;
total += show_free_zone(tiny_zone); if (tiny_alloc)
ft_putstr("SMALL:\n"); ft_putstr("TINY:");
total += show_free_zone(small_zone); ft_putstr(FG_RED);
printf("Total: %i bytes\n", total); alloc_total += show_zone(tiny_alloc, 0);
ft_putstr(FG_GREEN);
free_total += show_zone(tiny_zone, 1);
ft_putstr(FG_DEFAULT);
if (small_alloc)
ft_putstr("SMALL:");
ft_putstr(FG_RED);
alloc_total += show_zone(small_alloc, 0);
ft_putstr(FG_GREEN);
free_total += show_zone(small_zone, 1);
ft_putstr(FG_DEFAULT);
printf("Total:");
printf("\t%7zu bytes allocated\n", alloc_total);
printf("\t%7zu bytes free\n", free_total);
printf("\t%7zu bytes mapped\n", alloc_total + free_total);
} }