Unknown user: Created page with "= VMU = The following code will demonstrate how to write a compressed file to the VMU using KallistiOS. It is possible to just write raw data to the VMU, but in order for..."

2023-03-01T23:09:35Z

Created page with "= VMU = The following code will demonstrate how to write a compressed file to the VMU using KallistiOS. It is possible to just write raw data to the VMU, but in order for..."

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= VMU =

The following code will demonstrate how to write a compressed file to the VMU using [[KallistiOS]].
It is possible to just write raw data to the VMU, but in order for the file to show up properly in the VMU menu, a VMU package header with a description and icon is specified as well.

The following headers are required for the VMU header and compression.
#include <kos.h>
#include <zlib/zlib.h>

== Saving ==
The save function will write to the first controller's first VMU.

int DC_SaveToVMU(char *src) {
char dst[32];
file_t file;
int filesize = 0;
unsigned long zipsize = 0;
uint8 *data;
uint8 *zipdata;
vmu_pkg_t pkg;
uint8 *pkg_out;
int pkg_size;

// Our VMU + full save name
strcpy(dst, "/vmu/a1/");
strcat(dst, src);

// Reads in the file from the CWD
file = fs_open(src, O_RDONLY);
filesize = fs_total(file);
data = (uint8*)malloc(filesize);
fs_read(file, data, filesize);
fs_close(file);

// Allocate some memory for compression
zipsize = filesize * 2;
zipdata = (uint8*)malloc(zipsize);

// The compressed save
compress(zipdata, &zipsize, data, filesize);

// Required VMU header
// You will have to have a VMU icon defined under icon_data
strcpy(pkg.desc_short, "Wolf4SDL\\DC");
strcpy(pkg.desc_long, "Game Save");
strcpy(pkg.app_id, "Wolf4SDL\\DC");
pkg.icon_cnt = 1;
pkg.icon_anim_speed = 0;
memcpy(&pkg.icon_pal[0], icon_data, 32);
pkg.icon_data = icon_data + 32;
pkg.eyecatch_type = VMUPKG_EC_NONE;
pkg.data_len = zipsize;
pkg.data = zipdata;
vmu_pkg_build(&pkg, &pkg_out, &pkg_size);

// Save the newly created VMU save to the VMU
fs_unlink(dst);
file = fs_open(dst, O_WRONLY);
fs_write(file, pkg_out, pkg_size);
fs_close(file);

// Free unused memory
free(pkg_out);
free(data);
free(zipdata);

return 0;
}

== Loading ==
int DC_LoadFromVMU(char *dst) {
char src[32];
int file;
int filesize;
unsigned long unzipsize;
uint8* data;
uint8* unzipdata;
vmu_pkg_t pkg;

// Our VMU + full save name
strcpy(src, "/vmu/a1/");
strcat(src, dst);

// Remove VMU header
file = fs_open(src, O_RDONLY);
if(file == 0) return -1;
filesize = fs_total(file);
if(filesize <= 0) return -1;
data = (uint8*)malloc(filesize);
fs_read(file, data, filesize);
vmu_pkg_parse(data, &pkg);
fs_close(file);

// Allocate memory for the uncompressed data
unzipdata = (uint8 *)malloc(65536);
unzipsize = 65536;

// Uncompress the data to the CWD
uncompress(unzipdata, &unzipsize, (uint8 *)pkg.data, pkg.data_len);
fs_unlink(dst);
file = fs_open(dst, O_WRONLY);
fs_write(file, unzipdata, unzipsize);
fs_close(file);

// Free unused memory
free(data);
free(unzipdata);

return 0;
}

Save/Load file - Revision history

Unknown user: Created page with "= VMU = The following code will demonstrate how to write a compressed file to the VMU using KallistiOS. It is possible to just write raw data to the VMU, but in order for..."