39 lines
2.0 KiB
Plaintext
39 lines
2.0 KiB
Plaintext
$WW,1$$FG,5$$TX+CX,"RedSea File System"$$FG$
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The RedSea file system is a simple, 64-bit, file system which is, basically, FAT32 with fixed-sized 64-byte directory entries and no FAT table, just an allocation bitmap. It has no clustered-blocks, just 512 byte sectors. Files are stored in contiguous blocks and cannot grow in size.
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$HL,1$#define CDIR_FILENAME_LEN 38 //Must include terminator zero
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public class CDirEntry //64-byte fixed-size
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{
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U16 attr; //See $LK,"_ATTR_DIR",A="MN:_ATTR_DIR"$. I would like to change these.
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U8 name[CDIR_FILENAME_LEN]; //See $LK,"chars_bitmap_filename",A="MN:chars_bitmap_filename"$, $LK,"FileNameChk",A="MN:FileNameChk"$
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I64 cluster; //One sector per cluster. I might change origin, let's talk.
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I64 size; //In bytes
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CDate datetime; //See $LK,"DateTime",A="::/Doc/TimeDate.TXT"$, $LK,"Implementation of DateTime",A="FI:::/Kernel/Date.CPP"$
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};
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public class CBootStruct //RedSea is type FAT32 in partition table to fool BIOS
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{
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U8 jump_and_nop[3];
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U8 signature,reserved[4]; //MBR_PT_REDSEA=0x88. Distinguish from real FAT32
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I64 sects;
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I64 root_cluster;
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I64 bitmap_sects;
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I64 unique_id;
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U8 code[470];
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U16 signature2; //0xAA55
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};
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$HL,0$
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See $LK,"implementation of RedSea file system",A="::/Kernel/Dsk/FileSysRedSea.CPP"$.
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File with names ending in .Z are stored compressed.
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See $LK,"implementation of LZW compression",A="::/Kernel/Compress.CPP"$.
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I hope to do a ISO9660 replacement that consists of a hard-drive partition image copied onto a CD/DVD starting at about sector 20 with EL TORITO booting. 512-byte sectors will be placed on top of 2048-byte CD/DCD sectors, so there will be four blocks per CD/DVD sector.
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There is no bad block table and no redundant allocation table. When I was a teenager, I used a raw disk block editing program to look at directory blocks and follow chains of blocks on my Commodore 64. I undeleted files. My goal in designing the RedSea system is to be as simple as possible, for kids.
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$FG,8$
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* "Commodore 64" was a trademark of Commodore Business Machines.
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