#!/usr/bin/env python3
"""Split a raw SMBIOS structure table into one file per structure for QEMU.

Reads a dumped DMI table (/sys/firmware/dmi/tables/DMI on the real machine),
writes one `-smbios file=` blob per structure into OUTDIR, and prints the
ordered list of paths. A complete set through the type-127 end marker is what
lets QEMU build a well-formed entry point from a dump.

Each structure is a 4-byte header (type, length, handle:u16) + (length-4)
formatted bytes + a string set terminated by a double NUL; a structure with no
strings is still followed by 0x0000.
"""
import os
import sys


def split(data):
    out, i, n = [], 0, len(data)
    while i + 4 <= n:
        stype, slen = data[i], data[i + 1]
        if slen < 4:
            break
        j = i + slen
        while j + 1 < n and not (data[j] == 0 and data[j + 1] == 0):
            j += 1
        j += 2
        out.append((stype, data[i:j]))
        i = j
        if stype == 127:
            break
    return out


def main():
    dmi, outdir = sys.argv[1], sys.argv[2]
    data = open(dmi, "rb").read()
    os.makedirs(outdir, exist_ok=True)
    structs = split(data)
    paths = []
    for idx, (stype, blob) in enumerate(structs):
        p = os.path.join(outdir, "sm_%02d_type%d.bin" % (idx, stype))
        open(p, "wb").write(blob)
        paths.append(p)
    print("# %d structures: %s" % (len(structs), ",".join(str(t) for t, _ in structs)))
    for p in paths:
        print(p)


if __name__ == "__main__":
    main()