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structure X86_64Elf =
struct
(* get all the bytes off the input stream *)
fun input inStrm = let
fun lp (line, lines) =
if BinIO.endOfStream inStrm
then List.rev lines
else lp (BinIO.inputN(inStrm, 8), line :: lines)
val lines = lp(BinIO.inputN(inStrm, 8), [])
in
BinIO.closeIn inStrm;
lines
end
(* input the entire file *)
val inputFile = input o BinIO.openIn
(* extract the text segment from an obj file *)
fun extractTextSegment bytes = let
val bytesBeforeInsn = List.take(bytes, 8)
val insn = List.nth(bytes, 8)
val bytesAfterInsn = List.drop(bytes, 9)
in
(bytesBeforeInsn, insn, bytesAfterInsn)
end
(* send a list of bytes to the output stream *)
fun output (bytes, outStrm) = let
fun lp [] = BinIO.closeOut outStrm
| lp (l :: ls) = (
BinIO.output(outStrm, l);
lp ls)
in
lp bytes
end
(* take a byte-encoding of an instruction and pad it out to 8 bytes *)
fun encodeInstr bs =
Word8Vector.fromList(bs @ List.tabulate(8-(List.length bs), fn _ => 0wx00))
fun instrToElf (instr, obj) = let
(* copy in bytes from the object file *)
val bytes = inputFile obj
val (bs1, _, bs2) = extractTextSegment bytes
in
bs1 @ [encodeInstr instr] @ bs2
end
(* copy bytes to an object file *)
fun outputObjFile (objOut, objBytes) = output(objBytes, BinIO.openOut objOut)
(* takes an elf object file and an instruction, and outputs that instruction to its own elf object file *)
fun outputInstrToObj (elfObj, instr) =
outputObjFile("out."^elfObj, instrToElf(instr, elfObj))
fun doit () = outputInstrToObj("asm1.o", [0wxff, 0wxc2])
end
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