[rsync/rsync.git] / lib / pool_alloc.c

#include "rsync.h"

#define POOL_DEF_EXTENT	(32 * 1024)

struct alloc_pool
{
	size_t			size;		/* extent size		*/
	size_t			quantum;	/* allocation quantum	*/
	struct pool_extent	*extents;	/* top extent is "live" */
	void			(*bomb)();	/* function to call if
						 * malloc fails		*/
	int			flags;

	/* statistical data */
	unsigned long		e_created;	/* extents created	*/
	unsigned long		e_freed;	/* extents detroyed	*/
	int64			n_allocated;	/* calls to alloc	*/
	int64			n_freed;	/* calls to free	*/
	int64			b_allocated;	/* cum. bytes allocated	*/
	int64			b_freed;	/* cum. bytes freed	*/
};

struct pool_extent
{
	void			*start;		/* starting address	*/
	size_t			free;		/* free bytecount	*/
	size_t			bound;		/* bytes bound by padding,
						 * overhead and freed	*/
	struct pool_extent	*next;
};

struct align_test {
	void *foo;
	int64 bar;
};

#define MINALIGN	offsetof(struct align_test, bar)

/* Temporarily cast a void* var into a char* var when adding an offset (to
 * keep some compilers from complaining about the pointer arithmetic). */
#define PTR_ADD(b,o)	( (void*) ((char*)(b) + (o)) )

alloc_pool_t
pool_create(size_t size, size_t quantum, void (*bomb)(const char *), int flags)
{
	struct alloc_pool	*pool;

	if (!(pool = new(struct alloc_pool)))
		return pool;
	memset(pool, 0, sizeof (struct alloc_pool));

	pool->size = size	/* round extent size to min alignment reqs */
	    ? (size + MINALIGN - 1) & ~(MINALIGN - 1)
	    : POOL_DEF_EXTENT;
	if (flags & POOL_INTERN) {
		pool->size -= sizeof (struct pool_extent);
		flags |= POOL_APPEND;
	}
	pool->quantum = quantum ? quantum : MINALIGN;
	pool->bomb = bomb;
	pool->flags = flags;

	return pool;
}

void
pool_destroy(alloc_pool_t p)
{
	struct alloc_pool *pool = (struct alloc_pool *) p;
	struct pool_extent	*cur, *next;

	if (!pool)
		return;

	for (cur = pool->extents; cur; cur = next) {
		next = cur->next;
		free(cur->start);
		if (!(pool->flags & POOL_APPEND))
			free(cur);
	}
	free(pool);
}

void *
pool_alloc(alloc_pool_t p, size_t len, const char *bomb_msg)
{
	struct alloc_pool *pool = (struct alloc_pool *) p;
	if (!pool)
		return NULL;

	if (!len)
		len = pool->quantum;
	else if (pool->quantum > 1 && len % pool->quantum)
		len += pool->quantum - len % pool->quantum;

	if (len > pool->size)
		goto bomb_out;

	if (!pool->extents || len > pool->extents->free) {
		void	*start;
		size_t	free;
		size_t	bound;
		size_t	skew;
		size_t	asize;
		struct pool_extent *ext;

		free = pool->size;
		bound = 0;

		asize = pool->size;
		if (pool->flags & POOL_APPEND)
			asize += sizeof (struct pool_extent);

		if (!(start = new_array(char, asize)))
			goto bomb_out;

		if (pool->flags & POOL_CLEAR)
			memset(start, 0, free);

		if (pool->flags & POOL_APPEND)
			ext = PTR_ADD(start, free);
		else if (!(ext = new(struct pool_extent)))
			goto bomb_out;
		if (pool->flags & POOL_QALIGN && pool->quantum > 1
		    && (skew = (size_t)PTR_ADD(start, free) % pool->quantum)) {
			bound  += skew;
			free -= skew;
		}
		ext->start = start;
		ext->free = free;
		ext->bound = bound;
		ext->next = pool->extents;
		pool->extents = ext;

		pool->e_created++;
	}

	pool->n_allocated++;
	pool->b_allocated += len;

	pool->extents->free -= len;

	return PTR_ADD(pool->extents->start, pool->extents->free);

  bomb_out:
	if (pool->bomb)
		(*pool->bomb)(bomb_msg);
	return NULL;
}

/* This function allows you to declare memory in the pool that you are done
 * using.  If you free all the memory in a pool's extent, that extent will
 * be freed. */
void
pool_free(alloc_pool_t p, size_t len, void *addr)
{
	struct alloc_pool *pool = (struct alloc_pool *)p;
	struct pool_extent *cur, *prev;

	if (!pool)
		return;

	if (!len)
		len = pool->quantum;
	else if (pool->quantum > 1 && len % pool->quantum)
		len += pool->quantum - len % pool->quantum;

	pool->n_freed++;
	pool->b_freed += len;

	for (prev = NULL, cur = pool->extents; cur; prev = cur, cur = cur->next) {
		if (addr >= cur->start
		    && addr < PTR_ADD(cur->start, pool->size))
			break;
	}
	if (!cur)
		return;

	if (!prev) {
		/* The "live" extent is kept ready for more allocations. */
		if (cur->free + cur->bound + len >= pool->size) {
			size_t skew;

			if (pool->flags & POOL_CLEAR) {
				memset(PTR_ADD(cur->start, cur->free), 0,
				       pool->size - cur->free);
			}
			cur->free = pool->size;
			cur->bound = 0;
			if (pool->flags & POOL_QALIGN && pool->quantum > 1
			    && (skew = (size_t)PTR_ADD(cur->start, cur->free) % pool->quantum)) {
				cur->bound += skew;
				cur->free -= skew;
			}
		} else if (addr == PTR_ADD(cur->start, cur->free)) {
			if (pool->flags & POOL_CLEAR)
				memset(addr, 0, len);
			cur->free += len;
		} else
			cur->bound += len;
	} else {
		cur->bound += len;

		if (cur->free + cur->bound >= pool->size) {
			prev->next = cur->next;
			free(cur->start);
			if (!(pool->flags & POOL_APPEND))
				free(cur);
			pool->e_freed++;
		} else if (prev != pool->extents) {
			/* Move the extent to be the first non-live extent. */
			prev->next = cur->next;
			cur->next = pool->extents->next;
			pool->extents->next = cur;
		}
	}
}

/* This allows you to declare that the given address marks the edge of some
 * pool memory that is no longer needed.  Any extents that hold only data
 * older than the boundary address are freed.  NOTE: You MUST NOT USE BOTH
 * pool_free() and pool_free_old() on the same pool!! */
void
pool_free_old(alloc_pool_t p, void *addr)
{
	struct alloc_pool *pool = (struct alloc_pool *)p;
	struct pool_extent *cur, *prev, *next;

	if (!pool || !addr)
		return;

	for (prev = NULL, cur = pool->extents; cur; prev = cur, cur = cur->next) {
		if (addr >= cur->start
		    && addr < PTR_ADD(cur->start, pool->size))
			break;
	}
	if (!cur)
		return;

	if (addr == PTR_ADD(cur->start, cur->free)) {
		if (prev) {
			prev->next = NULL;
			next = cur;
		} else {
			size_t skew;

			/* The most recent live extent can just be reset. */
			if (pool->flags & POOL_CLEAR)
				memset(addr, 0, pool->size - cur->free);
			cur->free = pool->size;
			cur->bound = 0;
			if (pool->flags & POOL_QALIGN && pool->quantum > 1
			    && (skew = (size_t)PTR_ADD(cur->start, cur->free) % pool->quantum)) {
				cur->bound += skew;
				cur->free -= skew;
			}
			next = cur->next;
			cur->next = NULL;
		}
	} else {
		next = cur->next;
		cur->next = NULL;
	}

	while ((cur = next) != NULL) {
		next = cur->next;
		free(cur->start);
		if (!(pool->flags & POOL_APPEND))
			free(cur);
		pool->e_freed++;
	}
}

/* If the current extent doesn't have "len" free space in it, mark it as full
 * so that the next alloc will start a new extent.  If len is (size_t)-1, this
 * bump will always occur.  The function returns a boundary address that can
 * be used with pool_free_old(), or a NULL if no memory is allocated. */
void *
pool_boundary(alloc_pool_t p, size_t len)
{
	struct alloc_pool *pool = (struct alloc_pool *)p;
	struct pool_extent *cur;

	if (!pool || !pool->extents)
		return NULL;

	cur = pool->extents;

	if (cur->free < len) {
		cur->bound += cur->free;
		cur->free = 0;
	}

	return PTR_ADD(cur->start, cur->free);
}

#define FDPRINT(label, value) \
	snprintf(buf, sizeof buf, label, value), \
	write(fd, buf, strlen(buf))

#define FDEXTSTAT(ext) \
	snprintf(buf, sizeof buf, "  %12ld  %5ld\n", \
		(long) ext->free, \
		(long) ext->bound), \
	write(fd, buf, strlen(buf))

void
pool_stats(alloc_pool_t p, int fd, int summarize)
{
	struct alloc_pool *pool = (struct alloc_pool *) p;
	struct pool_extent	*cur;
	char buf[BUFSIZ];

	if (!pool)
		return;

	FDPRINT("  Extent size:       %12ld\n",	(long)	pool->size);
	FDPRINT("  Alloc quantum:     %12ld\n",	(long)	pool->quantum);
	FDPRINT("  Extents created:   %12ld\n",		pool->e_created);
	FDPRINT("  Extents freed:     %12ld\n",		pool->e_freed);
	FDPRINT("  Alloc count:       %12.0f\n", (double) pool->n_allocated);
	FDPRINT("  Free Count:        %12.0f\n", (double) pool->n_freed);
	FDPRINT("  Bytes allocated:   %12.0f\n", (double) pool->b_allocated);
	FDPRINT("  Bytes freed:       %12.0f\n", (double) pool->b_freed);

	if (summarize)
		return;

	if (!pool->extents)
		return;

	write(fd, "\n", 1);

	for (cur = pool->extents; cur; cur = cur->next)
		FDEXTSTAT(cur);
}
Commit	Line	Data
7efdcf32 S	1	#include "rsync.h"
	2
	3	#define POOL_DEF_EXTENT (32 * 1024)
	4
	5	struct alloc_pool
	6	{
	7	size_t size; /* extent size */
	8	size_t quantum; /* allocation quantum */
676e6041	9	struct pool_extent extents; / top extent is "live" */
e3d27df4	10	void (bomb)(); / function to call if
7efdcf32 S	11	* malloc fails */
	12	int flags;
	13
	14	/* statistical data */
	15	unsigned long e_created; /* extents created */
	16	unsigned long e_freed; /* extents detroyed */
707415d4 WD	17	int64 n_allocated; /* calls to alloc */
	18	int64 n_freed; /* calls to free */
	19	int64 b_allocated; /* cum. bytes allocated */
	20	int64 b_freed; /* cum. bytes freed */
7efdcf32 S	21	};
	22
	23	struct pool_extent
	24	{
	25	void start; / starting address */
	26	size_t free; /* free bytecount */
	27	size_t bound; /* bytes bound by padding,
	28	* overhead and freed */
	29	struct pool_extent *next;
	30	};
	31
4d4df3cd	32	struct align_test {
e3d27df4 WD	33	void *foo;
e3d27df4 WD	34	int64 bar;
4d4df3cd WD	35	};
	36
	37	#define MINALIGN offsetof(struct align_test, bar)
7efdcf32	38
71b291d7 WD	39	/* Temporarily cast a void* var into a char* var when adding an offset (to
	40	* keep some compilers from complaining about the pointer arithmetic). */
	41	#define PTR_ADD(b,o) ( (void) ((char)(b) + (o)) )
	42
7efdcf32	43	alloc_pool_t
4a19c3b2	44	pool_create(size_t size, size_t quantum, void (bomb)(const char ), int flags)
7efdcf32 S	45	{
	46	struct alloc_pool *pool;
	47
e3d27df4	48	if (!(pool = new(struct alloc_pool)))
7efdcf32 S	49	return pool;
	50	memset(pool, 0, sizeof (struct alloc_pool));
	51
	52	pool->size = size /* round extent size to min alignment reqs */
	53	? (size + MINALIGN - 1) & ~(MINALIGN - 1)
	54	: POOL_DEF_EXTENT;
a0f70237	55	if (flags & POOL_INTERN) {
7efdcf32 S	56	pool->size -= sizeof (struct pool_extent);
	57	flags \|= POOL_APPEND;
	58	}
	59	pool->quantum = quantum ? quantum : MINALIGN;
	60	pool->bomb = bomb;
	61	pool->flags = flags;
	62
	63	return pool;
	64	}
	65
	66	void
	67	pool_destroy(alloc_pool_t p)
	68	{
	69	struct alloc_pool pool = (struct alloc_pool ) p;
	70	struct pool_extent cur, next;
	71
	72	if (!pool)
	73	return;
	74
676e6041	75	for (cur = pool->extents; cur; cur = next) {
7efdcf32 S	76	next = cur->next;
	77	free(cur->start);
	78	if (!(pool->flags & POOL_APPEND))
	79	free(cur);
	80	}
	81	free(pool);
	82	}
	83
be20dc34	84	void *
3fac8ca8	85	pool_alloc(alloc_pool_t p, size_t len, const char *bomb_msg)
7efdcf32 S	86	{
	87	struct alloc_pool pool = (struct alloc_pool ) p;
	88	if (!pool)
15f85b1f	89	return NULL;
7efdcf32 S	90
	91	if (!len)
	92	len = pool->quantum;
	93	else if (pool->quantum > 1 && len % pool->quantum)
	94	len += pool->quantum - len % pool->quantum;
	95
	96	if (len > pool->size)
3fac8ca8	97	goto bomb_out;
7efdcf32	98
676e6041	99	if (!pool->extents \|\| len > pool->extents->free) {
7efdcf32 S	100	void *start;
	101	size_t free;
	102	size_t bound;
e3d27df4	103	size_t skew;
7efdcf32	104	size_t asize;
e3d27df4	105	struct pool_extent *ext;
7efdcf32	106
7efdcf32 S	107	free = pool->size;
	108	bound = 0;
	109
	110	asize = pool->size;
	111	if (pool->flags & POOL_APPEND)
	112	asize += sizeof (struct pool_extent);
	113
e3d27df4	114	if (!(start = new_array(char, asize)))
3fac8ca8	115	goto bomb_out;
7efdcf32 S	116
7efdcf32 S	117	if (pool->flags & POOL_CLEAR)
e3d27df4	118	memset(start, 0, free);
7efdcf32 S	119
7efdcf32 S	120	if (pool->flags & POOL_APPEND)
e3d27df4 WD	121	ext = PTR_ADD(start, free);
e3d27df4 WD	122	else if (!(ext = new(struct pool_extent)))
3fac8ca8	123	goto bomb_out;
7efdcf32	124	if (pool->flags & POOL_QALIGN && pool->quantum > 1
e3d27df4 WD	125	&& (skew = (size_t)PTR_ADD(start, free) % pool->quantum)) {
	126	bound += skew;
	127	free -= skew;
7efdcf32	128	}
e3d27df4 WD	129	ext->start = start;
	130	ext->free = free;
	131	ext->bound = bound;
676e6041 WD	132	ext->next = pool->extents;
676e6041 WD	133	pool->extents = ext;
7efdcf32 S	134
	135	pool->e_created++;
	136	}
	137
	138	pool->n_allocated++;
	139	pool->b_allocated += len;
	140
676e6041	141	pool->extents->free -= len;
7efdcf32	142
676e6041	143	return PTR_ADD(pool->extents->start, pool->extents->free);
7efdcf32	144
3fac8ca8	145	bomb_out:
7efdcf32	146	if (pool->bomb)
3fac8ca8	147	(*pool->bomb)(bomb_msg);
7efdcf32 S	148	return NULL;
	149	}
	150
e3d27df4 WD	151	/* This function allows you to declare memory in the pool that you are done
	152	* using. If you free all the memory in a pool's extent, that extent will
	153	* be freed. */
7efdcf32 S	154	void
	155	pool_free(alloc_pool_t p, size_t len, void *addr)
	156	{
e3d27df4 WD	157	struct alloc_pool pool = (struct alloc_pool )p;
e3d27df4 WD	158	struct pool_extent cur, prev;
7efdcf32 S	159
	160	if (!pool)
	161	return;
	162
	163	if (!len)
	164	len = pool->quantum;
	165	else if (pool->quantum > 1 && len % pool->quantum)
	166	len += pool->quantum - len % pool->quantum;
	167
7efdcf32 S	168	pool->n_freed++;
	169	pool->b_freed += len;
	170
676e6041 WD	171	for (prev = NULL, cur = pool->extents; cur; prev = cur, cur = cur->next) {
	172	if (addr >= cur->start
	173	&& addr < PTR_ADD(cur->start, pool->size))
	174	break;
	175	}
	176	if (!cur)
	177	return;
	178
	179	if (!prev) {
	180	/* The "live" extent is kept ready for more allocations. */
	181	if (cur->free + cur->bound + len >= pool->size) {
e3d27df4	182	size_t skew;
7efdcf32	183
e3d27df4 WD	184	if (pool->flags & POOL_CLEAR) {
	185	memset(PTR_ADD(cur->start, cur->free), 0,
	186	pool->size - cur->free);
	187	}
7efdcf32 S	188	cur->free = pool->size;
	189	cur->bound = 0;
	190	if (pool->flags & POOL_QALIGN && pool->quantum > 1
e3d27df4 WD	191	&& (skew = (size_t)PTR_ADD(cur->start, cur->free) % pool->quantum)) {
	192	cur->bound += skew;
	193	cur->free -= skew;
7efdcf32	194	}
676e6041 WD	195	} else if (addr == PTR_ADD(cur->start, cur->free)) {
	196	if (pool->flags & POOL_CLEAR)
	197	memset(addr, 0, len);
	198	cur->free += len;
	199	} else
	200	cur->bound += len;
	201	} else {
	202	cur->bound += len;
	203
	204	if (cur->free + cur->bound >= pool->size) {
	205	prev->next = cur->next;
	206	free(cur->start);
	207	if (!(pool->flags & POOL_APPEND))
	208	free(cur);
	209	pool->e_freed++;
	210	} else if (prev != pool->extents) {
	211	/* Move the extent to be the first non-live extent. */
	212	prev->next = cur->next;
	213	cur->next = pool->extents->next;
	214	pool->extents->next = cur;
7efdcf32	215	}
7efdcf32	216	}
676e6041 WD	217	}
	218
	219	/* This allows you to declare that the given address marks the edge of some
	220	* pool memory that is no longer needed. Any extents that hold only data
	221	* older than the boundary address are freed. NOTE: You MUST NOT USE BOTH
	222	* pool_free() and pool_free_old() on the same pool!! */
	223	void
	224	pool_free_old(alloc_pool_t p, void *addr)
	225	{
	226	struct alloc_pool pool = (struct alloc_pool )p;
	227	struct pool_extent cur, prev, *next;
	228
8b498b9f	229	if (!pool \|\| !addr)
676e6041 WD	230	return;
	231
	232	for (prev = NULL, cur = pool->extents; cur; prev = cur, cur = cur->next) {
7efdcf32	233	if (addr >= cur->start
04575bca	234	&& addr < PTR_ADD(cur->start, pool->size))
7efdcf32 S	235	break;
	236	}
	237	if (!cur)
	238	return;
	239
676e6041 WD	240	if (addr == PTR_ADD(cur->start, cur->free)) {
	241	if (prev) {
	242	prev->next = NULL;
	243	next = cur;
	244	} else {
	245	size_t skew;
7efdcf32	246
676e6041 WD	247	/* The most recent live extent can just be reset. */
	248	if (pool->flags & POOL_CLEAR)
	249	memset(addr, 0, pool->size - cur->free);
	250	cur->free = pool->size;
	251	cur->bound = 0;
	252	if (pool->flags & POOL_QALIGN && pool->quantum > 1
	253	&& (skew = (size_t)PTR_ADD(cur->start, cur->free) % pool->quantum)) {
	254	cur->bound += skew;
	255	cur->free -= skew;
	256	}
	257	next = cur->next;
65a22a5f	258	cur->next = NULL;
676e6041 WD	259	}
	260	} else {
	261	next = cur->next;
	262	cur->next = NULL;
	263	}
7efdcf32	264
676e6041 WD	265	while ((cur = next) != NULL) {
676e6041 WD	266	next = cur->next;
7efdcf32 S	267	free(cur->start);
	268	if (!(pool->flags & POOL_APPEND))
	269	free(cur);
	270	pool->e_freed++;
	271	}
7efdcf32 S	272	}
7efdcf32 S	273
676e6041 WD	274	/* If the current extent doesn't have "len" free space in it, mark it as full
	275	* so that the next alloc will start a new extent. If len is (size_t)-1, this
	276	* bump will always occur. The function returns a boundary address that can
	277	* be used with pool_free_old(), or a NULL if no memory is allocated. */
	278	void *
	279	pool_boundary(alloc_pool_t p, size_t len)
	280	{
	281	struct alloc_pool pool = (struct alloc_pool )p;
	282	struct pool_extent *cur;
	283
	284	if (!pool \|\| !pool->extents)
	285	return NULL;
	286
	287	cur = pool->extents;
	288
	289	if (cur->free < len) {
	290	cur->bound += cur->free;
	291	cur->free = 0;
	292	}
	293
	294	return PTR_ADD(cur->start, cur->free);
	295	}
	296
7efdcf32	297	#define FDPRINT(label, value) \
8ea17b50 WD	298	snprintf(buf, sizeof buf, label, value), \
8ea17b50 WD	299	write(fd, buf, strlen(buf))
7efdcf32 S	300
7efdcf32 S	301	#define FDEXTSTAT(ext) \
8ea17b50	302	snprintf(buf, sizeof buf, " %12ld %5ld\n", \
7efdcf32 S	303	(long) ext->free, \
	304	(long) ext->bound), \
	305	write(fd, buf, strlen(buf))
	306
	307	void
	308	pool_stats(alloc_pool_t p, int fd, int summarize)
	309	{
	310	struct alloc_pool pool = (struct alloc_pool ) p;
	311	struct pool_extent *cur;
	312	char buf[BUFSIZ];
	313
	314	if (!pool)
	315	return;
	316
	317	FDPRINT(" Extent size: %12ld\n", (long) pool->size);
	318	FDPRINT(" Alloc quantum: %12ld\n", (long) pool->quantum);
	319	FDPRINT(" Extents created: %12ld\n", pool->e_created);
	320	FDPRINT(" Extents freed: %12ld\n", pool->e_freed);
	321	FDPRINT(" Alloc count: %12.0f\n", (double) pool->n_allocated);
	322	FDPRINT(" Free Count: %12.0f\n", (double) pool->n_freed);
e3d27df4 WD	323	FDPRINT(" Bytes allocated: %12.0f\n", (double) pool->b_allocated);
e3d27df4 WD	324	FDPRINT(" Bytes freed: %12.0f\n", (double) pool->b_freed);
7efdcf32 S	325
	326	if (summarize)
	327	return;
	328
676e6041	329	if (!pool->extents)
7efdcf32 S	330	return;
	331
	332	write(fd, "\n", 1);
	333
676e6041	334	for (cur = pool->extents; cur; cur = cur->next)
7efdcf32	335	FDEXTSTAT(cur);
7efdcf32	336	}