/*************************************************************************
* (C) 2012 AITNET ltd - Sofia/Bulgaria - <misho@elwix.org>
*  by Michael Pounov <misho@openbsd-bg.org>
*
* $Author: misho $
* $Id: mem.c,v 1.8 2017/11/30 13:46:27 misho Exp $
*
**************************************************************************
The ELWIX and AITNET software is distributed under the following
terms:

All of the documentation and software included in the ELWIX and AITNET
Releases is copyrighted by ELWIX - Sofia/Bulgaria <info@elwix.org>

Copyright 2004 - 2017
	by Michael Pounov <misho@elwix.org>.  All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
3. All advertising materials mentioning features or use of this software
   must display the following acknowledgement:
This product includes software developed by Michael Pounov <misho@elwix.org>
ELWIX - Embedded LightWeight unIX and its contributors.
4. Neither the name of AITNET nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY AITNET AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
*/
#include "global.h"


mpool_t *elwix_mpool;


/*
 * mpool_init() - Init memory pool
 *
 * @maxmem = If !=0 set maximum memory quota
 * return: =NULL error or !=NULL new allocated pool
 */
mpool_t *
mpool_init(u_long maxmem)
{
	mpool_t *mp;
	register int i;

	mp = malloc(sizeof(mpool_t));
	if (!mp) {
		LOGERR;
		return NULL;
	} else
		memset(mp, 0, sizeof(mpool_t));

	pthread_mutex_init(&mp->pool_mtx, NULL);

	mp->pool_quota.max = maxmem;

	mpool_lock(mp);
	for (i = 0; i < MEM_BUCKETS; i++) {
		TAILQ_INIT(&mp->pool_active[i]);
		TAILQ_INIT(&mp->pool_inactive[i]);
	}
	mpool_unlock(mp);

	return mp;
}

/*
 * mpool_destroy() - Destroy memory pool
 *
 * @mp = Memory pool
 * return: none
 */
void
mpool_destroy(mpool_t ** __restrict mp)
{
	struct tagAlloc *m;
	register int i;

	if (!mp && !*mp)
		return;

	mpool_lock(*mp);

	for (i = 0; i < MEM_BUCKETS; i++) {
		while ((m = TAILQ_FIRST(&(*mp)->pool_active[i]))) {
			TAILQ_REMOVE(&(*mp)->pool_active[i], m, alloc_node);
			if (m->alloc_mem)
				free(m->alloc_mem);
			free(m);
		}
		while ((m = TAILQ_FIRST(&(*mp)->pool_inactive[i]))) {
			TAILQ_REMOVE(&(*mp)->pool_inactive[i], m, alloc_node);
			if (m->alloc_mem)
				free(m->alloc_mem);
			free(m);
		}
	}

	mpool_unlock(*mp);
	pthread_mutex_destroy(&(*mp)->pool_mtx);

	free(*mp);
	*mp = NULL;
}

/* ----------------------------------------------------------- */

static inline long
BucketIndex(u_int size)
{
	register long b;

	if (!size--)
		return 0;		/* min bucket position in array */

	for (b = MEM_MIN_BUCKET; b < MEM_MAX_BUCKET; b++)
		if (!(size >> b))
			break;

	return b - MEM_MIN_BUCKET;	/* convert to bucket array index */
}

static inline struct tagAlloc *
pullInactive(mpool_t * __restrict mp, int idx)
{
	struct tagAlloc *m = NULL;

	/* must be locked pool before use this function */ 
	if ((m = TAILQ_FIRST(&mp->pool_inactive[idx]))) {
		TAILQ_REMOVE(&mp->pool_inactive[idx], m, alloc_node);
		/* statistics */
		mp->pool_calls.cache--;
		mp->pool_bytes.cache -= mem_size(m);

		/* clear name */
		*m->alloc_name = 0;
	}

	return m;
}

/*
 * mpool_malloc() - Memory allocation
 *
 * @mp = Memory pool
 * @size = Size
 * @memname = Optional memory block name
 * return: NULL error or !=NULL ok allocated memory
 */
void *
mpool_malloc(mpool_t * __restrict mp, u_int size, const char *memname)
{
	struct tagAlloc *m;
	int idx;
	u_int align;

	if (!mp) {
		elwix_SetErr(EINVAL, "Pool not specified");
		return NULL;
	}
	if (size > MEM_ALLOC_MAX) {
		elwix_SetErr(ENOMEM, "Memory size is too large");
		return NULL;
	} else
		size = (size + 3) & ~3;	/* must align to 4 because needed room for sentinels */

	idx = BucketIndex(size);

	mpool_lock(mp);

	/* get memory from cache if exists */
	if (!(m = pullInactive(mp, idx))) {
		/* quota */
		if (mp->pool_quota.max && 
				(mp->pool_quota.curr + size) > mp->pool_quota.max) {
			elwix_SetErr(ENOMEM, "Max.allocate memory quota has been reached");
			mpool_unlock(mp);
			return NULL;
		}

		m = malloc(sizeof(struct tagAlloc));
		if (!m) {
			LOGERR;
			mpool_unlock(mp);
			return NULL;
		} else
			memset(m, 0, sizeof(struct tagAlloc));
	}

	if (memname)
		strlcpy(m->alloc_name, memname, sizeof m->alloc_name);

	if (!m->alloc_mem) {
		align = 1 << (idx + MEM_MIN_BUCKET);
		m->alloc_mem = malloc(align + 12);	/* +12 sentinel bytes */
		if (!m->alloc_mem) {
			LOGERR;
			free(m);
			mpool_unlock(mp);
			return NULL;
		} else {	/* quota */
			mp->pool_quota.curr += size;
			mp->pool_quota.real += 1 << (idx + MEM_MIN_BUCKET);
			memset(m->alloc_mem, 0, align + 12);
		}
	}

	m->alloc_mem[0] = size / sizeof(u_int);
	m->alloc_mem[1] = MEM_MAGIC_START;
	m->alloc_mem[2 + size / sizeof(u_int)] = MEM_MAGIC_STOP;
	TAILQ_INSERT_HEAD(&mp->pool_active[idx], m, alloc_node);
	/* statistics */
	mp->pool_calls.alloc++;
	mp->pool_bytes.alloc += size;

	mpool_unlock(mp);
	return mem_data(m, void*);
}

/*
 * mpool_realloc() Reallocate memory block with new size
 *
 * @mp = Memory pool
 * @data = Allocated memory data
 * @newsize = New size of memory block
 * @memname = Optional new memory block name
 * return: NULL error or !=NULL new reallocated memory block
 */
void *
mpool_realloc(mpool_t * __restrict mp, void * __restrict data, u_int newsize, const char *memname)
{
	int idx, oidx;
	void *p;
	u_int osize;

	/* if !data execute mpool_malloc() */
	if (!data)
		return mpool_malloc(mp, newsize, memname);

	if (!mp) {
		elwix_SetErr(EINVAL, "Pool not specified");
		return NULL;
	}
	/* check address range & sentinel */
	if (MEM_BADADDR(data) || MEM_CORRUPT(data)) {
		elwix_SetErr(EFAULT, "Corrupted memory address");
		return NULL;
	}
	/* prepare new size */
	if (newsize > MEM_ALLOC_MAX) {
		elwix_SetErr(ENOMEM, "Memory size is too large");
		return NULL;
	}

	mpool_lock(mp);

	osize = ((u_int*)data)[-2] * sizeof(u_int);
	oidx = BucketIndex(osize);
	newsize = (newsize + 3) & ~3;	/* must align to 4 because needed room for sentinels */
	idx = BucketIndex(newsize);

	/* quota */
	if (mp->pool_quota.max && 
			(mp->pool_quota.curr + ((u_long) newsize - osize)) > mp->pool_quota.max) {
		elwix_SetErr(ENOMEM, "Max.allocate memory quota has been reached");
		mpool_unlock(mp);
		return NULL;
	}

	if (oidx != idx) {
		mpool_unlock(mp);
		p = mpool_malloc(mp, newsize, memname);
		if (!p)
			return NULL;

		memcpy(p, data, MIN(osize, newsize));
		mpool_free(mp, data, 0);
		data = p;
	} else {
		p = data;

		((u_int*) p)[-2] = newsize / sizeof(u_int);
		((u_int*) p)[newsize / sizeof(u_int)] = MEM_MAGIC_STOP;

		mp->pool_bytes.alloc += (u_long) newsize - osize;
		mp->pool_quota.curr += (u_long) newsize - osize;

		mpool_unlock(mp);
	}

	return p;
}

/*
 * mpool_purge() - Purge memory block cache and release resources
 *
 * @mp = Memory pool
 * @atmost = Free at most in buckets
 * return: -1 error or 0 ok
 */
int
mpool_purge(mpool_t * __restrict mp, u_int atmost)
{
	register int i, cx;
	struct tagAlloc *m, *tmp;

	if (!mp) {
		elwix_SetErr(EINVAL, "Pool not specified");
		return -1;
	}

	mpool_lock(mp);

	for (i = cx = 0; i < MEM_BUCKETS; cx = 0, i++) {
		TAILQ_FOREACH_SAFE(m, &mp->pool_inactive[i], alloc_node, tmp) {
			/* barrier for purge */
			if (cx < atmost) {
				cx++;
				continue;
			}

			TAILQ_REMOVE(&mp->pool_inactive[i], m, alloc_node);
			/* statistics */
			mp->pool_calls.cache--;
			mp->pool_bytes.cache -= mem_size(m);

			mp->pool_calls.free++;
			mp->pool_bytes.free += mem_size(m);
			/* quota */
			mp->pool_quota.curr -= mem_size(m);
			mp->pool_quota.real -= 1 << (i + MEM_MIN_BUCKET);

			if (m->alloc_mem)
				free(m->alloc_mem);
			free(m);
		}
	}

	mpool_unlock(mp);
	return 0;
}

/*
 * mpool_free() Free allocated memory with mpool_alloc()
 *
 * @mp = Memory pool
 * @data = Allocated memory data
 * @purge = if !=0 force release memory block
 * return: <0 error or 0 ok released memory block
 */
int
mpool_free(mpool_t * __restrict mp, void * __restrict data, int purge)
{
	int idx;
	struct tagAlloc *m, *tmp;

	if (!data)
		return 0;
	if (!mp) {
		elwix_SetErr(EINVAL, "Pool not specified");
		return -1;
	}
	/* check address range & sentinel */
	assert(!MEM_BADADDR(data) && !MEM_CORRUPT(data));
	if (MEM_BADADDR(data) || MEM_CORRUPT(data)) {
		elwix_SetErr(EFAULT, "Corrupted memory address");
		return -2;
	} else
		idx = BucketIndex(((u_int*)data)[-2] * sizeof(u_int));

	mpool_lock(mp);
	TAILQ_FOREACH_SAFE(m, &mp->pool_active[idx], alloc_node, tmp)
		if (mem_data(m, void*) == data) {
			TAILQ_REMOVE(&mp->pool_active[idx], m, alloc_node);
			/* statistics */
			mp->pool_calls.alloc--;
			mp->pool_bytes.alloc -= mem_size(m);

			if (!purge) {
				TAILQ_INSERT_HEAD(&mp->pool_inactive[idx], m, alloc_node);
				/* statistics */
				mp->pool_calls.cache++;
				mp->pool_bytes.cache += mem_size(m);
			} else {
				/* statistics */
				mp->pool_calls.free++;
				mp->pool_bytes.free += mem_size(m);
				/* quota */
				mp->pool_quota.curr -= mem_size(m);
				mp->pool_quota.real -= 1 << (idx + MEM_MIN_BUCKET);

				if (m->alloc_mem)
					free(m->alloc_mem);
				free(m);
			}
			break;
		}
	mpool_unlock(mp);

	return 0;
}

/*
 * mpool_free2() Free allocated memory with mpool_alloc() by size and memory name
 *
 * @mp = Memory pool
 * @size = Allocated memory data size
 * @memname = Memory name
 * @purge = if !=0 force release memory block
 * return: <0 error or 0 ok released memory block
 */
int
mpool_free2(mpool_t * __restrict mp, u_int size, const char *memname, int purge)
{
	int idx;
	struct tagAlloc *m, *tmp;

	if (!mp || !memname) {
		elwix_SetErr(EINVAL, "Pool or memory name is not specified");
		return -1;
	} else
		idx = BucketIndex(size);

	mpool_lock(mp);
	TAILQ_FOREACH_SAFE(m, &mp->pool_active[idx], alloc_node, tmp)
		if (!strcmp(m->alloc_name, memname)) {
			TAILQ_REMOVE(&mp->pool_active[idx], m, alloc_node);
			/* statistics */
			mp->pool_calls.alloc--;
			mp->pool_bytes.alloc -= mem_size(m);

			if (!purge) {
				TAILQ_INSERT_HEAD(&mp->pool_inactive[idx], m, alloc_node);
				/* statistics */
				mp->pool_calls.cache++;
				mp->pool_bytes.cache += mem_size(m);
			} else {
				/* statistics */
				mp->pool_calls.free++;
				mp->pool_bytes.free += mem_size(m);
				/* quota */
				mp->pool_quota.curr -= mem_size(m);
				mp->pool_quota.real -= 1 << (idx + MEM_MIN_BUCKET);

				if (m->alloc_mem)
					free(m->alloc_mem);
				free(m);
			}
			break;
		}
	mpool_unlock(mp);

	return 0;
}

/*
 * mpool_strdup() - String duplicate
 *
 * @mp = Memory pool
 * @str = String
 * @memname = Memory name
 * return: NULL error or !=NULL new string
 */
char *
mpool_strdup(mpool_t * __restrict mp, const char *str, const char *memname)
{
	char *s = NULL;
	u_int len;

	if (!mp) {
		elwix_SetErr(EINVAL, "Pool not specified");
		return NULL;
	}
	if (!str) {
		elwix_SetErr(EINVAL, "String is NULL");
		return NULL;
	} else
		len = strlen(str) + 1;

	s = mpool_malloc(mp, len, memname);
	if (!s)
		return NULL;
	else
		memcpy(s, str, len);

	return s;
}

/*
 * mpool_getmembynam() Find allocated memory block by size and memory name
 *
 * @mp = Memory pool
 * @size = Memory size
 * @memname = Memory name
 * return: NULL error or not found and !=NULL allocated memory 
 */
struct tagAlloc *
mpool_getmembynam(mpool_t * __restrict mp, u_int size, const char *memname)
{
	int idx;
	struct tagAlloc *m = NULL;

	if (!mp || !memname)
		return NULL;

	idx = BucketIndex(size);
	TAILQ_FOREACH(m, &mp->pool_active[idx], alloc_node)
		if (!strcmp(m->alloc_name, memname))
			break;

	return mem_data(m, void*);
}

/*
 * mpool_getsizebyaddr() - Get size of allocated memory block by address
 *
 * @addr = allocated memory from mpool_malloc()
 * return: usable size of allocated memory block
 */
u_int
mpool_getsizebyaddr(void * __restrict data)
{
	if (mpool_chkaddr(data))
		return 0;

	return (((u_int*) data)[-2] * sizeof(u_int));
}

/*
 * mpool_chkaddr() - Check validity of given address
 *
 * @data = allocated memory from mpool_malloc()
 * return: -1 bad address, 1 corrupted address or 0 ok
 */
int
mpool_chkaddr(void * __restrict data)
{
	/* check address range */
	if (MEM_BADADDR(data))
		return -1;
	/* check sentinel */
	if (MEM_CORRUPT(data))
		return 1;
	/* data address is ok! */
	return 0;
}

/*
 * mpool_setquota() - Change maximum memory quota
 *
 * @mp = Memory pool
 * @maxmem = New max quota size
 * return: old maximum memory quota size
 */
u_long
mpool_setquota(mpool_t * __restrict mp, u_long maxmem)
{
	u_long ret;

	if (!mp)
		return 0;

	ret = mp->pool_quota.max;
	mp->pool_quota.max = maxmem;

	/* if new max quota is less then current allocated memory, 
	 * 	try to purge memory cache blocks
	 */
	if (mp->pool_quota.max < mp->pool_quota.curr)
		mpool_purge(mp, 0);

	return ret;
}

/*
 * mpool_getquota() - Get memory quota
 *
 * @mp = Memory pool
 * @currmem = Return current memory usage
 * @realmem = Return current real memory usage
 * @maxmem = Return max quota size
 * return: none
 */
void
mpool_getquota(mpool_t * __restrict mp, u_long *currmem, u_long *realmem, u_long *maxmem)
{
	if (!mp)
		return;

	if (maxmem)
		*maxmem = mp->pool_quota.max;
	if (realmem)
		*realmem = mp->pool_quota.real;
	if (currmem)
		*currmem = mp->pool_quota.curr;
}

/* ----------------------------------------------------------- */

/*
 * mpool_statistics() - Dump statistics from memory pool buckets
 *
 * @mp = Memory pool
 * @cb = Export statistics to callback
 * return: none
 */
void
mpool_statistics(mpool_t * __restrict mp, mpool_stat_cb cb)
{
	struct tagAlloc *m;
	register int i, act, inact;

	if (!mp || !cb)
		return;

	for (i = act = inact = 0; i < MEM_BUCKETS; act = inact = 0, i++) {
		TAILQ_FOREACH(m, &mp->pool_active[i], alloc_node)
			act++;
		TAILQ_FOREACH(m, &mp->pool_inactive[i], alloc_node)
			inact++;

		cb(1 << (i + MEM_MIN_BUCKET), act, inact);
	}
}

/* ----------------------------------------------------------- */

/*
 * mpool_xmalloc() - malloc wrapper
 *
 * @size = Size
 * return: NULL error or !=NULL ok allocated memory
 */
void *
mpool_xmalloc(size_t size)
{
	return mpool_malloc(elwix_mpool, size, elwix_Prog);
}

/*
 * mpool_xcalloc() - calloc wrapper
 *
 * @num = number of elements
 * @size = Size of element
 * return: NULL error or !=NULL ok allocated memory
 */
void *
mpool_xcalloc(size_t num, size_t size)
{
	return mpool_malloc(elwix_mpool, num * size, elwix_Prog);
}

/*
 * mpool_xrealloc() - realloc wrapper
 *
 * @data = Allocated memory data
 * @newsize = New size of memory block
 * return: NULL error or !=NULL new reallocated memory block
 */
void *
mpool_xrealloc(void * __restrict data, size_t newsize)
{
	return mpool_realloc(elwix_mpool, data, newsize, elwix_Prog);
}

/*
 * mpool_xfree() - free wrapper
 *
 * @data = Allocated memory data
 * return: none
 */
void
mpool_xfree(void * __restrict data)
{
	mpool_free(elwix_mpool, data, 0);
}

/*
 * mpool_xstrdup() - strdup wrapper
 *
 * @str = string
 * return: =NULL error or !=NULL new allocated string
 */
char *
mpool_xstrdup(const char *str)
{
	return mpool_strdup(elwix_mpool, str, elwix_Prog);
}

/*
 * mpool_xstatistics() - elwix memory pool statistics wrapper
 *
 * @cb = Export statistics to callback
 * return: none
 */
void
mpool_xstatistics(mpool_stat_cb cb)
{
	mpool_statistics(elwix_mpool, cb);
}

static void
xdump_show(u_int size, u_int act, u_int inact)
{
	if (!act && !inact)
		return;	/* skip empty bucket */

	if (size < 1024)
		printf("\t\t* BUCKET %uB size, %u active, %u inactive\n", 
				size, act, inact);
	else if (size < 1048576)
		printf("\t\t* BUCKET %uKB size, %u active, %u inactive\n", 
				size / 1024, act, inact);
	else
		printf("\t\t* BUCKET %uMB size, %u active, %u inactive\n", 
				size / 1048576, act, inact);
}

/*
 * mpool_dump() - Dump elwix memory pool statistics
 *
 * @mp = memory pool, if =NULL dump elwix default memory pool
 * @fmt = prefix info format string
 * @... = argument(s)
 * return: none
 */
void
mpool_dump(mpool_t * __restrict mp, const char *fmt, ...)
{
	va_list lst;
	mpool_t *p = mp ? mp : elwix_mpool;

	if (fmt) {
		va_start(lst, fmt);
		vprintf(fmt, lst);
		va_end(lst);
	} else
		printf("\n%s(%d)\n", __func__, __LINE__);

	printf("------------------------------------------------------------\n");
	printf( " ELWIX memory pool ::\n"
		"\t- quotas Current/Real/Max = %lu/%lu/%lu\n"
		"\t- calls Alloc/Free/Cache = %lu/%lu/%lu\n"
		"\t- bytes Alloc/Free/Cache = %lu/%lu/%lu\n"
		"\t- buckets :\n", 
		p->pool_quota.curr, p->pool_quota.real, p->pool_quota.max, 
		p->pool_calls.alloc, p->pool_calls.free, p->pool_calls.cache, 
		p->pool_bytes.alloc, p->pool_bytes.free, p->pool_bytes.cache);

	mpool_statistics(p, xdump_show);
	printf("------------------------------------------------------------\n");
}