customdata_file.c

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/*
 * $Id: customdata_file.c 35247 2011-02-27 20:40:57Z jesterking $
 *
 * ***** 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.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

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

#include "MEM_guardedalloc.h"

#include "BLI_fileops.h"
#include "BLI_string.h"
#include "BLI_utildefines.h"

#include "BKE_customdata_file.h"
#include "BKE_global.h"


/************************* File Format Definitions ***************************/

#define CDF_ENDIAN_LITTLE       0
#define CDF_ENDIAN_BIG          1

#define CDF_DATA_FLOAT  0

typedef struct CDataFileHeader {
        char ID[4];                                     /* "BCDF" */
        char endian;                            /* little, big */
        char version;                           /* non-compatible versions */
        char subversion;                        /* compatible sub versions */
        char pad;                                       /* padding */

        int structbytes;                        /* size of this struct in bytes */
        int type;                                       /* image, mesh */
        int totlayer;                           /* number of layers in the file */
} CDataFileHeader;

typedef struct CDataFileImageHeader {
        int structbytes;                        /* size of this struct in bytes */
        int width;                                      /* image width */
        int height;                                     /* image height */
        int tile_size;                          /* tile size (required power of 2) */
} CDataFileImageHeader;

typedef struct CDataFileMeshHeader {
        int structbytes;                        /* size of this struct in bytes */
} CDataFileMeshHeader;

struct CDataFileLayer {
        int structbytes;                                /* size of this struct in bytes */
        int datatype;                                   /* only float for now */
        uint64_t datasize;                              /* size of data in layer */
        int type;                                               /* layer type */
        char name[CDF_LAYER_NAME_MAX];  /* layer name */
};

/**************************** Other Definitions ******************************/

#define CDF_VERSION                     0
#define CDF_SUBVERSION          0
#define CDF_TILE_SIZE           64

struct CDataFile {
        int type;

        CDataFileHeader header;
        union {
                CDataFileImageHeader image;
                CDataFileMeshHeader mesh;
        } btype;

        CDataFileLayer *layer;
        int totlayer;

        FILE *readf;
        FILE *writef;
        int switchendian;
        size_t dataoffset;
};

/********************************* Create/Free *******************************/

static int cdf_endian(void)
{
        if(ENDIAN_ORDER == L_ENDIAN)
                return CDF_ENDIAN_LITTLE;
        else
                return CDF_ENDIAN_BIG;
}

/*static int cdf_data_type_size(int datatype)
{
        if(datatype == CDF_DATA_FLOAT)
                return sizeof(float);
        
        return 0;
}*/

CDataFile *cdf_create(int type)
{
        CDataFile *cdf= MEM_callocN(sizeof(CDataFile), "CDataFile");

        cdf->type= type;

        return cdf;
}

void cdf_free(CDataFile *cdf)
{
        cdf_read_close(cdf);
        cdf_write_close(cdf);

        if(cdf->layer)
                MEM_freeN(cdf->layer);

        MEM_freeN(cdf);
}

/********************************* Read/Write ********************************/

static int cdf_read_header(CDataFile *cdf)
{
        CDataFileHeader *header;
        CDataFileImageHeader *image;
        CDataFileMeshHeader *mesh;
        CDataFileLayer *layer;
        FILE *f= cdf->readf;
        size_t offset = 0;
        int a;

        header= &cdf->header;

        if(!fread(header, sizeof(CDataFileHeader), 1, cdf->readf))
                return 0;
        
        if(memcmp(header->ID, "BCDF", sizeof(header->ID)) != 0)
                return 0;
        if(header->version > CDF_VERSION)
                return 0;

        cdf->switchendian= header->endian != cdf_endian();
        header->endian= cdf_endian();

        if(cdf->switchendian) {
                SWITCH_INT(header->type);
                SWITCH_INT(header->totlayer);
                SWITCH_INT(header->structbytes);
        }

        if(!ELEM(header->type, CDF_TYPE_IMAGE, CDF_TYPE_MESH))
                return 0;

        offset += header->structbytes;
        header->structbytes= sizeof(CDataFileHeader);

        if(fseek(f, offset, SEEK_SET) != 0)
                return 0;
        
        if(header->type == CDF_TYPE_IMAGE) {
                image= &cdf->btype.image;
                if(!fread(image, sizeof(CDataFileImageHeader), 1, f))
                        return 0;

                if(cdf->switchendian) {
                        SWITCH_INT(image->width);
                        SWITCH_INT(image->height);
                        SWITCH_INT(image->tile_size);
                        SWITCH_INT(image->structbytes);
                }

                offset += image->structbytes;
                image->structbytes= sizeof(CDataFileImageHeader);
        }
        else if(header->type == CDF_TYPE_MESH) {
                mesh= &cdf->btype.mesh;
                if(!fread(mesh, sizeof(CDataFileMeshHeader), 1, f))
                        return 0;

                if(cdf->switchendian)
                        SWITCH_INT(mesh->structbytes);

                offset += mesh->structbytes;
                mesh->structbytes= sizeof(CDataFileMeshHeader);
        }

        if(fseek(f, offset, SEEK_SET) != 0)
                return 0;

        cdf->layer= MEM_callocN(sizeof(CDataFileLayer)*header->totlayer, "CDataFileLayer");
        cdf->totlayer= header->totlayer;

        for(a=0; a<header->totlayer; a++) {
                layer= &cdf->layer[a];

                if(!fread(layer, sizeof(CDataFileLayer), 1, f))
                        return 0;

                if(cdf->switchendian) {
                        SWITCH_INT(layer->type);
                        SWITCH_INT(layer->datatype);
                        SWITCH_INT64(layer->datasize);
                        SWITCH_INT(layer->structbytes);
                }

                if(layer->datatype != CDF_DATA_FLOAT)
                        return 0;

                offset += layer->structbytes;
                layer->structbytes= sizeof(CDataFileLayer);

                if(fseek(f, offset, SEEK_SET) != 0)
                        return 0;
        }

        cdf->dataoffset= offset;

        return 1;
}

static int cdf_write_header(CDataFile *cdf)
{
        CDataFileHeader *header;
        CDataFileImageHeader *image;
        CDataFileMeshHeader *mesh;
        CDataFileLayer *layer;
        FILE *f= cdf->writef;
        int a;

        header= &cdf->header;

        if(!fwrite(header, sizeof(CDataFileHeader), 1, f))
                return 0;
        
        if(header->type == CDF_TYPE_IMAGE) {
                image= &cdf->btype.image;
                if(!fwrite(image, sizeof(CDataFileImageHeader), 1, f))
                        return 0;
        }
        else if(header->type == CDF_TYPE_MESH) {
                mesh= &cdf->btype.mesh;
                if(!fwrite(mesh, sizeof(CDataFileMeshHeader), 1, f))
                        return 0;
        }

        for(a=0; a<header->totlayer; a++) {
                layer= &cdf->layer[a];

                if(!fwrite(layer, sizeof(CDataFileLayer), 1, f))
                        return 0;
        }

        return 1;
}

int cdf_read_open(CDataFile *cdf, char *filename)
{
        FILE *f;

        f= fopen(filename, "rb");
        if(!f)
                return 0;
        
        cdf->readf= f;

        if(!cdf_read_header(cdf)) {
                cdf_read_close(cdf);
                return 0;
        }

        if(cdf->header.type != cdf->type) {
                cdf_read_close(cdf);
                return 0;
        }

        return 1;
}

int cdf_read_layer(CDataFile *cdf, CDataFileLayer *blay)
{
        size_t offset;
        int a;

        /* seek to right location in file */
        offset= cdf->dataoffset;
        for(a=0; a<cdf->totlayer; a++) {
                if(&cdf->layer[a] == blay)
                        break;
                else
                        offset += cdf->layer[a].datasize;
        }

        return (fseek(cdf->readf, offset, SEEK_SET) == 0);
}

int cdf_read_data(CDataFile *cdf, unsigned int size, void *data)
{
        float *fdata;
        unsigned int a;

        /* read data */
        if(!fread(data, size, 1, cdf->readf))
                return 0;

        /* switch endian if necessary */
        if(cdf->switchendian) {
                fdata= data;

                for(a=0; a<size/sizeof(float); a++)
                        SWITCH_INT(fdata[a])
        }

        return 1;
}

void cdf_read_close(CDataFile *cdf)
{
        if(cdf->readf) {
                fclose(cdf->readf);
                cdf->readf= NULL;
        }
}

int cdf_write_open(CDataFile *cdf, char *filename)
{
        CDataFileHeader *header;
        CDataFileImageHeader *image;
        CDataFileMeshHeader *mesh;
        FILE *f;

        f= fopen(filename, "wb");
        if(!f)
                return 0;
        
        cdf->writef= f;

        /* fill header */
        header= &cdf->header;
        /* strcpy(, "BCDF"); // terminator out of range */
        header->ID[0]= 'B'; header->ID[1]= 'C'; header->ID[2]= 'D'; header->ID[3]= 'F';
        header->endian= cdf_endian();
        header->version= CDF_VERSION;
        header->subversion= CDF_SUBVERSION;

        header->structbytes= sizeof(CDataFileHeader);
        header->type= cdf->type;
        header->totlayer= cdf->totlayer;

        if(cdf->type == CDF_TYPE_IMAGE) {
                /* fill image header */
                image= &cdf->btype.image;
                image->structbytes= sizeof(CDataFileImageHeader);
                image->tile_size= CDF_TILE_SIZE;
        }
        else if(cdf->type == CDF_TYPE_MESH) {
                /* fill mesh header */
                mesh= &cdf->btype.mesh;
                mesh->structbytes= sizeof(CDataFileMeshHeader);
        }

        cdf_write_header(cdf);

        return 1;
}

int cdf_write_layer(CDataFile *UNUSED(cdf), CDataFileLayer *UNUSED(blay))
{
        return 1;
}

int cdf_write_data(CDataFile *cdf, unsigned int size, void *data)
{
        /* write data */
        if(!fwrite(data, size, 1, cdf->writef))
                return 0;

        return 1;
}

void cdf_write_close(CDataFile *cdf)
{
        if(cdf->writef) {
                fclose(cdf->writef);
                cdf->writef= NULL;
        }
}

void cdf_remove(char *filename)
{
        BLI_delete(filename, 0, 0);
}

/********************************** Layers ***********************************/

CDataFileLayer *cdf_layer_find(CDataFile *cdf, int type, char *name)
{
        CDataFileLayer *layer;
        int a;

        for(a=0; a<cdf->totlayer; a++) {
                layer= &cdf->layer[a];

                if(layer->type == type && strcmp(layer->name, name) == 0)
                        return layer;
        }
        
        return NULL;
}

CDataFileLayer *cdf_layer_add(CDataFile *cdf, int type, char *name, size_t datasize)
{
        CDataFileLayer *newlayer, *layer;

        /* expand array */
        newlayer= MEM_callocN(sizeof(CDataFileLayer)*(cdf->totlayer+1), "CDataFileLayer");
        memcpy(newlayer, cdf->layer, sizeof(CDataFileLayer)*cdf->totlayer);
        cdf->layer= newlayer;

        cdf->totlayer++;

        /* fill in new layer */
        layer= &cdf->layer[cdf->totlayer-1];
        layer->structbytes= sizeof(CDataFileLayer);
        layer->datatype= CDF_DATA_FLOAT;
        layer->datasize= datasize;
        layer->type= type;
        BLI_strncpy(layer->name, name, CDF_LAYER_NAME_MAX);

        return layer;
}