Files
Vladimir Serbinenko 9bfb7638ae Convert to VFS
New code behaves the same way as old
2022-04-14 03:42:32 +02:00

238 lines
6.9 KiB
C++

/*
(The MIT License)
Copyright (c) 2013 Håkon Nessjøen <[email protected]>
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
#define SKIP_STDIO_REDEFINES 1
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <ctype.h>
#include <sys/types.h>
#include <stdio.h>
#include <math.h>
#include <retro_dirent.h>
#include <vfs/vfs_implementation.h>
#include <streams/file_stream_transforms.h>
#include "SDEmulator.h"
/* bootsector jump instruction */
unsigned char bootjmp[3] = { 0xeb, 0x3c, 0x90 };
unsigned char oem_name[8] = "uzemSDe";
static int posBootsector;
static int posFatSector;
static int posRootDir;
static int posDataSector;
static int clusterSize;
static bool hexDebug=false;
extern struct retro_vfs_interface *vfs_interface;
void SDEmu::debug(bool value){
hexDebug=value;
}
static void long2shortfilename(char *dst, const char *src) {
int i;
for (i = 0; i < 8; ++i) {
if (*src == '.') {
dst+=8-i;
break;
}
*dst++ = toupper(*src++);
}
const char *dot = strchr(src, '.') + 1;
if (dot > src) {
for (i = 0; i < 3; ++i) {
if (*dot != 0) {
*dst++ = toupper(*dot++);
}
}
}
}
int SDEmu::init_with_directory(const char *path) {
int i;
//2G SD card, 32k per cluster FAT16
memcpy(&bootsector.bootjmp, bootjmp, 3);
memcpy(&bootsector.oem_name, oem_name, 8);
bootsector.bytes_per_sector = 512;
bootsector.sectors_per_cluster =64; //32K cluster size
bootsector.reserved_sector_count = 1;
bootsector.table_count = 2;
bootsector.root_entry_count = 512;
bootsector.total_sectors_16 = 0;
bootsector.media_type = 0xF8;
bootsector.sectors_per_fat = 0x76; //1024; /* Update ? */
bootsector.sectors_per_track = 32;
bootsector.head_side_count = 32;
bootsector.hidden_sector_count = 0;
bootsector.total_sectors_32 = 3854201; /* remember: file system id in mbr must be 06 */
bootsector.drive_no = 4;
bootsector.extended_fields = 0x29;
bootsector.serial_number = 1234567;
memcpy(&bootsector.volume_label, "UZEBOX ", 11);
memcpy(&bootsector.filesystem_type, "FAT16", 5);
bootsector.signature[0] = 0x55;
bootsector.signature[1] = 0xAA;
posBootsector = 0;
posFatSector = bootsector.bytes_per_sector + (bootsector.reserved_sector_count * bootsector.bytes_per_sector);
posRootDir = posFatSector + (bootsector.table_count * (bootsector.sectors_per_fat * bootsector.bytes_per_sector));
posDataSector = posRootDir + (((bootsector.root_entry_count * 32) / bootsector.bytes_per_sector) * bootsector.bytes_per_sector);
clusterSize = bootsector.bytes_per_sector*bootsector.sectors_per_cluster;
RDIR *dir = retro_opendir(path);
if (dir == NULL) {
return -1;
}
memcpy(toc[0].name,"UZEBOX ",8);
memcpy(toc[0].ext," ",3);
toc[0].attrib = SDEFA_ARCHIVE | SDEFA_VOLUME_ID;
i = 1;
int freecluster = 2;
printf("SD Emulation of following files:\n");
while (retro_readdir(dir)) {
const char *d_name = retro_dirent_get_name(dir);
if (d_name[0] != '.') {
char *statpath = (char *)malloc(strlen(path) + strlen(d_name) + 2);
int statflags = 0;
int32_t stat_size = 0;
strcpy(statpath, path);
strcat(statpath, "/");
strcat(statpath, d_name);
if (vfs_interface)
statflags = vfs_interface->stat(statpath, &stat_size);
else
statflags = retro_vfs_stat_impl(statpath, &stat_size);
if (!(statflags & RETRO_VFS_STAT_IS_VALID) || (statflags & (RETRO_VFS_STAT_IS_DIRECTORY | RETRO_VFS_STAT_IS_CHARACTER_SPECIAL)))
continue;
paths[i] = statpath;
memset(toc[i].name, 32, 11);
long2shortfilename((char *)toc[i].name, d_name);
toc[i].attrib = SDEFA_ARCHIVE;
toc[i].cluster_no = freecluster;
//Fill the FAT with the file's cluster chain
int fileClustersCount=ceil(stat_size / (bootsector.sectors_per_cluster * 512.0f));
for(int j=freecluster;j<(freecluster+fileClustersCount-1);j++){
clusters[j]=j+1;
}
clusters[freecluster+fileClustersCount-1]=0xffff; //Last cluster in file marker (EOC)
toc[i].filesize = stat_size;
printf("\t%d: %s:%ld\n", i, d_name, stat_size);
freecluster += fileClustersCount;
if (++i == MAX_FILES) {
break;
}
}
}
return 0;
}
void SDEmu::read(unsigned char *ptr) {
static int lastfile=-1;
static int lastfileStart=0;
static int lastfileEnd=0;
static RFILE *fp=0;
static int lastPos=0;
int pos;
unsigned char c;
// < 512 Bootsector
if (position < posFatSector) {
pos = position - bootsector.bytes_per_sector;
unsigned char *boot = (unsigned char *)&bootsector;
if (pos < sizeof(bootsector)) {
*ptr++ = *(boot + (pos));
} else {
*ptr++ = 0;
}
} else
// Fat table
if (position < posRootDir) {
pos = position - posFatSector;
//printf("sdemu: reading fat: %d\n", pos);
unsigned char *table = (unsigned char *)&clusters;
*ptr++ = *(table + pos);
}
else if (position < posDataSector) {
pos = position - posRootDir;
unsigned char *table = (unsigned char *)&toc;
*ptr++ = *(table + pos);
} else {
int cluster=-1;
pos = position - posDataSector;
if (lastfile == -1 || pos < lastfileStart || pos > lastfileEnd) {
int i;
lastfile = -1;
for (i = 0; i < MAX_FILES; ++i) {
cluster = (pos/512/bootsector.sectors_per_cluster) + 2;
if (toc[i].name[0] != 0 && cluster >= toc[i].cluster_no && cluster <= toc[i].cluster_no + (toc[i].filesize/512/bootsector.sectors_per_cluster)) {
lastfile = i;
lastfileStart = (toc[i].cluster_no-2)*clusterSize;
lastfileEnd = lastfileStart + (((toc[i].filesize/clusterSize)+1)*clusterSize)-1; //account for cluster size padding
if (fp != NULL) {
rfclose(fp);
}
//printf("Opening file: %s, start=%d, end=%d, cluster=%d\n", paths[i],lastfileStart,lastfileEnd, cluster);
fp = rfopen(paths[i], "rb");
lastPos=-1;
break;
}
}
}
if (lastfile == -1 || fp == NULL) { *ptr++ = 0; }
else {
if(pos!=(lastPos+1)){
rfseek(fp, pos - ((toc[lastfile].cluster_no-2)*clusterSize), SEEK_SET);
}
if(pos<(lastfileStart+toc[lastfile].filesize)){
c= rfgetc(fp);
}else{
c=0;
}
lastPos=pos;
*ptr++ =c;
}
}
position++;
}
void SDEmu::seek(int pos) {
position = pos;
}