undofile.c

Go to the documentation of this file.

/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2004 Blender Foundation
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 * .blend file reading entry point
 */

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <math.h>

#include "MEM_guardedalloc.h"

#include "DNA_listBase.h"


#include "BLO_undofile.h"

#include "BLI_blenlib.h"
#include "BLI_linklist.h"



/* **************** support for memory-write, for undo buffers *************** */

/* not memfile itself */
void BLO_free_memfile(MemFile *memfile)
{
    MemFileChunk *chunk;
    
    while( (chunk = (memfile->chunks.first) ) ) {
        if(chunk->ident==0) MEM_freeN(chunk->buf);
        BLI_remlink(&memfile->chunks, chunk);
        MEM_freeN(chunk);
    }
    memfile->size= 0;
}

/* to keep list of memfiles consistent, 'first' is always first in list */
/* result is that 'first' is being freed */
void BLO_merge_memfile(MemFile *first, MemFile *second)
{
    MemFileChunk *fc, *sc;
    
    fc= first->chunks.first;
    sc= second->chunks.first;
    while (fc || sc) {
        if(fc && sc) {
            if(sc->ident) {
                sc->ident= 0;
                fc->ident= 1;
            }
        }
        if(fc) fc= fc->next;
        if(sc) sc= sc->next;
    }
    
    BLO_free_memfile(first);
}

static int my_memcmp(int *mem1, int *mem2, int len)
{
    register int a= len, *mema= mem1, *memb= mem2;
    
    while(a--) {
        if( *mema != *memb) return 1;
        mema++;
        memb++;
    }
    return 0;
}

void add_memfilechunk(MemFile *compare, MemFile *current, char *buf, unsigned int size)
{
    static MemFileChunk *compchunk=NULL;
    MemFileChunk *curchunk;
    
    /* this function inits when compare != NULL or when current==NULL */
    if(compare) {
        compchunk= compare->chunks.first;
        return;
    }
    if(current==NULL) {
        compchunk= NULL;
        return;
    }
    
    curchunk= MEM_mallocN(sizeof(MemFileChunk), "MemFileChunk");
    curchunk->size= size;
    curchunk->buf= NULL;
    curchunk->ident= 0;
    BLI_addtail(&current->chunks, curchunk);
    
    /* we compare compchunk with buf */
    if(compchunk) {
        if(compchunk->size == curchunk->size) {
            if( my_memcmp((int *)compchunk->buf, (int *)buf, size/4)==0) {
                curchunk->buf= compchunk->buf;
                curchunk->ident= 1;
            }
        }
        compchunk= compchunk->next;
    }
    
    /* not equal... */
    if(curchunk->buf==NULL) {
        curchunk->buf= MEM_mallocN(size, "Chunk buffer");
        memcpy(curchunk->buf, buf, size);
        current->size += size;
    }
}