/*

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program 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 General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

 *

 *  Jabber

 *  Copyright (C) 1998-1999 The Jabber Team http://jabber.org/

 *  

 *  2/27/00:3am, random plans by jer

 *  

 *  ok based on gprof, we really need some innovation here... my thoughs are this:

 *  

 *  most things are strings, so have a string-based true-blue garbage collector

 *  one big global hash containing all the strings created by any pstrdup, returning const char *

 *  a refcount on each string block

 *  when a pool is freed, it moves down the refcount

 *  garbage collector collects pools on the free stack, and runs through the hash for unused strings

 *  j_strcmp can check for == (if they are both from a pstrdup)

 *  

 *  let's see... this would change:

 *  pstrdup: do a hash lookup, success=return, fail=pmalloc & hash put

 *  pool_free: 

 *  

 *  

 *  

 *  

 *  

 */

#include "libxode.h"

#ifdef POOL_DEBUG

int pool__total = 0;

int pool__ltotal = 0;

HASHTABLE pool__disturbed = NULL;

void *_pool__malloc(size_t size)

{

    pool__total++;

    return malloc(size);

}

void _pool__free(void *block)

{

    pool__total--;

    free(block);

}

#else

#define _pool__malloc malloc

#define _pool__free free

#endif

/* make an empty pool */

pool _pool_new(char *zone)

{

    pool p;

    while((p = _pool__malloc(sizeof(_pool))) == NULL) sleep(1);

    p->cleanup = NULL;

    p->heap = NULL;

    p->size = 0;

#ifdef POOL_DEBUG

    p->lsize = -1;

    p->zone[0] = '\0';

    strcat(p->zone,zone);

    sprintf(p->name,"%X",p);

    if(pool__disturbed == NULL)

	pool__disturbed = ghash_create(POOL_DEBUG,(KEYHASHFUNC)str_hash_code,(KEYCOMPAREFUNC)j_strcmp);

    ghash_put(pool__disturbed,p->name,p);

#endif

    return p;

}

/* free a heap */

void _pool_heap_free(void *arg)

{

    struct pheap *h = (struct pheap *)arg;

    _pool__free(h->block);

    _pool__free(h);

}

/* mem should always be freed last */

void _pool_cleanup_append(pool p, struct pfree *pf)

{

    struct pfree *cur;

    if(p->cleanup == NULL)

    {

	p->cleanup = pf;

	return;

    }

    /* fast forward to end of list */

    for(cur = p->cleanup; cur->next != NULL; cur = cur->next);

    cur->next = pf;

}

/* create a cleanup tracker */

struct pfree *_pool_free(pool p, pool_cleaner f, void *arg)

{

    struct pfree *ret;

    /* make the storage for the tracker */

    while((ret = _pool__malloc(sizeof(struct pfree))) == NULL) sleep(1);

    ret->f = f;

    ret->arg = arg;

    ret->next = NULL;

    return ret;

}

/* create a heap and make sure it get's cleaned up */

struct pheap *_pool_heap(pool p, int size)

{

    struct pheap *ret;

    struct pfree *clean;

    /* make the return heap */

    while((ret = _pool__malloc(sizeof(struct pheap))) == NULL) sleep(1);

    while((ret->block = _pool__malloc(size)) == NULL) sleep(1);

    ret->size = size;

    p->size += size;

    ret->used = 0;

    /* append to the cleanup list */

    clean = _pool_free(p, _pool_heap_free, (void *)ret);

    clean->heap = ret; /* for future use in finding used mem for pstrdup */

    _pool_cleanup_append(p, clean);

    return ret;

}

pool _pool_new_heap(int size, char *zone)

{

    pool p;

    p = _pool_new(zone);

    p->heap = _pool_heap(p,size);

    return p;

}

void *pmalloc(pool p, int size)

{

    void *block;

    if(p == NULL)

    {

	fprintf(stderr,"Memory Leak! [pmalloc received NULL pool, unable to track allocation, exiting]\n");

	abort();

    }

    /* if there is no heap for this pool or it's a big request, just raw, I like how we clean this :) */

    if(p->heap == NULL || size > (p->heap->size / 2))

    {

	while((block = _pool__malloc(size)) == NULL) sleep(1);

	p->size += size;

	_pool_cleanup_append(p, _pool_free(p, _pool__free, block));

	return block;

    }

    /* we have to preserve boundaries, long story :) */

    if(size >= 4)

	while(p->heap->used&7) p->heap->used++;

    /* if we don't fit in the old heap, replace it */

    if(size > (p->heap->size - p->heap->used))

	p->heap = _pool_heap(p, p->heap->size);

    /* the current heap has room */

    block = (char *)p->heap->block + p->heap->used;

    p->heap->used += size;

    return block;

}

void *pmalloc_x(pool p, int size, char c)

{

   void* result = pmalloc(p, size);

   if (result != NULL)

	   memset(result, c, size);

   return result;

}  

/* easy safety utility (for creating blank mem for structs, etc) */

void *pmalloco(pool p, int size)

{

    void *block = pmalloc(p, size);

    memset(block, 0, size);

    return block;

}  

/* XXX efficient: move this to const char * and then loop throug the existing heaps to see if src is within a block in this pool */

char *pstrdup(pool p, const char *src)

{

    char *ret;

    if(src == NULL)

	return NULL;

    ret = pmalloc(p,strlen(src) + 1);

    strcpy(ret,src);

    return ret;

}

/* when move above, this one would actually return a new block */

char *pstrdupx(pool p, const char *src)

{

    return pstrdup(p, src);

}

int pool_size(pool p)

{

    if(p == NULL) return 0;

    return p->size;

}

void pool_free(pool p)

{

    struct pfree *cur, *stub;

    if(p == NULL) return;

    cur = p->cleanup;

    while(cur != NULL)

    {

	(*cur->f)(cur->arg);

	stub = cur->next;

	_pool__free(cur);

	cur = stub;

    }

#ifdef POOL_DEBUG

    ghash_remove(pool__disturbed,p->name);

#endif

    _pool__free(p);

}

/* public cleanup utils, insert in a way that they are run FIFO, before mem frees */

void pool_cleanup(pool p, pool_cleaner f, void *arg)

{

    struct pfree *clean;

    clean = _pool_free(p, f, arg);

    clean->next = p->cleanup;

    p->cleanup = clean;

}

#ifdef POOL_DEBUG

void debug_log(char *zone, const char *msgfmt, ...);

int _pool_stat(void *arg, const void *key, void *data)

{

    pool p = (pool)data;

    if(p->lsize == -1)

	debug_log("leak","%s: %X is a new pool",p->zone,p->name);

    else if(p->size > p->lsize)

	debug_log("leak","%s: %X grew %d",p->zone,p->name, p->size - p->lsize);

    else if((int)arg)

	debug_log("leak","%s: %X exists %d",p->zone,p->name, p->size);

    p->lsize = p->size;

    return 1;

}

void pool_stat(int full)

{

    ghash_walk(pool__disturbed,_pool_stat,(void *)full);

    if(pool__total != pool__ltotal)

	debug_log("leak","%d\ttotal missed mallocs",pool__total);

    pool__ltotal = pool__total;

    return;

}

#else

void pool_stat(int full)

{

    return;

}

#endif